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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * vvvvvvvvvvvvvvvvvvvvvvv Original vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
  *  Copyright (C) 1992  Eric Youngdale
  *  Simulate a host adapter with 2 disks attached.  Do a lot of checking
  *  to make sure that we are not getting blocks mixed up, and PANIC if
  *  anything out of the ordinary is seen.
  * ^^^^^^^^^^^^^^^^^^^^^^^ Original ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  *
  * Copyright (C) 2001 - 2021 Douglas Gilbert
  *
  *  For documentation see http://sg.danny.cz/sg/scsi_debug.html
  */
 
 
 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
 
 #include <linux/module.h>
 #include <linux/align.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/jiffies.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
 #include <linux/vmalloc.h>
 #include <linux/moduleparam.h>
 #include <linux/scatterlist.h>
 #include <linux/blkdev.h>
 #include <linux/crc-t10dif.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/atomic.h>
 #include <linux/hrtimer.h>
 #include <linux/uuid.h>
 #include <linux/t10-pi.h>
 #include <linux/msdos_partition.h>
 #include <linux/random.h>
 #include <linux/xarray.h>
 #include <linux/prefetch.h>
 
 #include <net/checksum.h>
 
 #include <asm/unaligned.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsicam.h>
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_tcq.h>
 #include <scsi/scsi_dbg.h>
 
 #include "sd.h"
 #include "scsi_logging.h"
 
 /* make sure inq_product_rev string corresponds to this version */
 #define SDEBUG_VERSION "0191"   /* format to fit INQUIRY revision field */
 static const char *sdebug_version_date = "20210520";
 
 #define MY_NAME "scsi_debug"
 
 /* Additional Sense Code (ASC) */
 #define NO_ADDITIONAL_SENSE 0x0
 #define LOGICAL_UNIT_NOT_READY 0x4
 #define LOGICAL_UNIT_COMMUNICATION_FAILURE 0x8
 #define UNRECOVERED_READ_ERR 0x11
 #define PARAMETER_LIST_LENGTH_ERR 0x1a
 #define INVALID_OPCODE 0x20
 #define LBA_OUT_OF_RANGE 0x21
 #define INVALID_FIELD_IN_CDB 0x24
 #define INVALID_FIELD_IN_PARAM_LIST 0x26
 #define WRITE_PROTECTED 0x27
 #define UA_RESET_ASC 0x29
 #define UA_CHANGED_ASC 0x2a
 #define TARGET_CHANGED_ASC 0x3f
 #define LUNS_CHANGED_ASCQ 0x0e
 #define INSUFF_RES_ASC 0x55
 #define INSUFF_RES_ASCQ 0x3
 #define POWER_ON_RESET_ASCQ 0x0
 #define POWER_ON_OCCURRED_ASCQ 0x1
 #define BUS_RESET_ASCQ 0x2  /* scsi bus reset occurred */
 #define MODE_CHANGED_ASCQ 0x1   /* mode parameters changed */
 #define CAPACITY_CHANGED_ASCQ 0x9
 #define SAVING_PARAMS_UNSUP 0x39
 #define TRANSPORT_PROBLEM 0x4b
 #define THRESHOLD_EXCEEDED 0x5d
 #define LOW_POWER_COND_ON 0x5e
 #define MISCOMPARE_VERIFY_ASC 0x1d
 #define MICROCODE_CHANGED_ASCQ 0x1  /* with TARGET_CHANGED_ASC */
 #define MICROCODE_CHANGED_WO_RESET_ASCQ 0x16
 #define WRITE_ERROR_ASC 0xc
 #define UNALIGNED_WRITE_ASCQ 0x4
 #define WRITE_BOUNDARY_ASCQ 0x5
 #define READ_INVDATA_ASCQ 0x6
 #define READ_BOUNDARY_ASCQ 0x7
 #define ATTEMPT_ACCESS_GAP 0x9
 #define INSUFF_ZONE_ASCQ 0xe
 
 /* Additional Sense Code Qualifier (ASCQ) */
 #define ACK_NAK_TO 0x3
 
 /* Default values for driver parameters */
 #define DEF_NUM_HOST   1
 #define DEF_NUM_TGTS   1
 #define DEF_MAX_LUNS   1
 /* With these defaults, this driver will make 1 host with 1 target
  * (id 0) containing 1 logical unit (lun 0). That is 1 device.
  */
 #define DEF_ATO 1
 #define DEF_CDB_LEN 10
 #define DEF_JDELAY   1      /* if > 0 unit is a jiffy */
 #define DEF_DEV_SIZE_PRE_INIT   0
 #define DEF_DEV_SIZE_MB   8
 #define DEF_ZBC_DEV_SIZE_MB   128
 #define DEF_DIF 0
 #define DEF_DIX 0
 #define DEF_PER_HOST_STORE false
 #define DEF_D_SENSE   0
 #define DEF_EVERY_NTH   0
 #define DEF_FAKE_RW 0
 #define DEF_GUARD 0
 #define DEF_HOST_LOCK 0
 #define DEF_LBPU 0
 #define DEF_LBPWS 0
 #define DEF_LBPWS10 0
 #define DEF_LBPRZ 1
 #define DEF_LOWEST_ALIGNED 0
 #define DEF_NDELAY   0      /* if > 0 unit is a nanosecond */
 #define DEF_NO_LUN_0   0
 #define DEF_NUM_PARTS   0
 #define DEF_OPTS   0
 #define DEF_OPT_BLKS 1024
 #define DEF_PHYSBLK_EXP 0
 #define DEF_OPT_XFERLEN_EXP 0
 #define DEF_PTYPE   TYPE_DISK
 #define DEF_RANDOM false
 #define DEF_REMOVABLE false
 #define DEF_SCSI_LEVEL   7    /* INQUIRY, byte2 [6->SPC-4; 7->SPC-5] */
 #define DEF_SECTOR_SIZE 512
 #define DEF_UNMAP_ALIGNMENT 0
 #define DEF_UNMAP_GRANULARITY 1
 #define DEF_UNMAP_MAX_BLOCKS 0xFFFFFFFF
 #define DEF_UNMAP_MAX_DESC 256
 #define DEF_VIRTUAL_GB   0
 #define DEF_VPD_USE_HOSTNO 1
 #define DEF_WRITESAME_LENGTH 0xFFFF
 #define DEF_STRICT 0
 #define DEF_STATISTICS false
 #define DEF_SUBMIT_QUEUES 1
 #define DEF_TUR_MS_TO_READY 0
 #define DEF_UUID_CTL 0
 #define JDELAY_OVERRIDDEN -9999
 
 /* Default parameters for ZBC drives */
 #define DEF_ZBC_ZONE_SIZE_MB    128
 #define DEF_ZBC_MAX_OPEN_ZONES  8
 #define DEF_ZBC_NR_CONV_ZONES   1
 
 #define SDEBUG_LUN_0_VAL 0
 
 /* bit mask values for sdebug_opts */
 #define SDEBUG_OPT_NOISE        1
 #define SDEBUG_OPT_MEDIUM_ERR       2
 #define SDEBUG_OPT_TIMEOUT      4
 #define SDEBUG_OPT_RECOVERED_ERR    8
 #define SDEBUG_OPT_TRANSPORT_ERR    16
 #define SDEBUG_OPT_DIF_ERR      32
 #define SDEBUG_OPT_DIX_ERR      64
 #define SDEBUG_OPT_MAC_TIMEOUT      128
 #define SDEBUG_OPT_SHORT_TRANSFER   0x100
 #define SDEBUG_OPT_Q_NOISE      0x200
 #define SDEBUG_OPT_ALL_TSF      0x400   /* ignore */
 #define SDEBUG_OPT_RARE_TSF     0x800
 #define SDEBUG_OPT_N_WCE        0x1000
 #define SDEBUG_OPT_RESET_NOISE      0x2000
 #define SDEBUG_OPT_NO_CDB_NOISE     0x4000
 #define SDEBUG_OPT_HOST_BUSY        0x8000
 #define SDEBUG_OPT_CMD_ABORT        0x10000
 #define SDEBUG_OPT_ALL_NOISE (SDEBUG_OPT_NOISE | SDEBUG_OPT_Q_NOISE | \
                   SDEBUG_OPT_RESET_NOISE)
 #define SDEBUG_OPT_ALL_INJECTING (SDEBUG_OPT_RECOVERED_ERR | \
                   SDEBUG_OPT_TRANSPORT_ERR | \
                   SDEBUG_OPT_DIF_ERR | SDEBUG_OPT_DIX_ERR | \
                   SDEBUG_OPT_SHORT_TRANSFER | \
                   SDEBUG_OPT_HOST_BUSY | \
                   SDEBUG_OPT_CMD_ABORT)
 #define SDEBUG_OPT_RECOV_DIF_DIX (SDEBUG_OPT_RECOVERED_ERR | \
                   SDEBUG_OPT_DIF_ERR | SDEBUG_OPT_DIX_ERR)
 
 /* As indicated in SAM-5 and SPC-4 Unit Attentions (UAs) are returned in
  * priority order. In the subset implemented here lower numbers have higher
  * priority. The UA numbers should be a sequence starting from 0 with
  * SDEBUG_NUM_UAS being 1 higher than the highest numbered UA. */
 #define SDEBUG_UA_POR 0     /* Power on, reset, or bus device reset */
 #define SDEBUG_UA_POOCCUR 1 /* Power on occurred */
 #define SDEBUG_UA_BUS_RESET 2
 #define SDEBUG_UA_MODE_CHANGED 3
 #define SDEBUG_UA_CAPACITY_CHANGED 4
 #define SDEBUG_UA_LUNS_CHANGED 5
 #define SDEBUG_UA_MICROCODE_CHANGED 6   /* simulate firmware change */
 #define SDEBUG_UA_MICROCODE_CHANGED_WO_RESET 7
 #define SDEBUG_NUM_UAS 8
 
 /* when 1==SDEBUG_OPT_MEDIUM_ERR, a medium error is simulated at this
  * sector on read commands: */
 #define OPT_MEDIUM_ERR_ADDR   0x1234 /* that's sector 4660 in decimal */
 #define OPT_MEDIUM_ERR_NUM    10     /* number of consecutive medium errs */
 
 /* SDEBUG_CANQUEUE is the maximum number of commands that can be queued
  * (for response) per submit queue at one time. Can be reduced by max_queue
  * option. Command responses are not queued when jdelay=0 and ndelay=0. The
  * per-device DEF_CMD_PER_LUN can be changed via sysfs:
  * /sys/class/scsi_device/<h:c:t:l>/device/queue_depth
  * but cannot exceed SDEBUG_CANQUEUE .
  */
 #define SDEBUG_CANQUEUE_WORDS  3    /* a WORD is bits in a long */
 #define SDEBUG_CANQUEUE  (SDEBUG_CANQUEUE_WORDS * BITS_PER_LONG)
 #define DEF_CMD_PER_LUN  SDEBUG_CANQUEUE
 
 /* UA - Unit Attention; SA - Service Action; SSU - Start Stop Unit */
 #define F_D_IN          1   /* Data-in command (e.g. READ) */
 #define F_D_OUT         2   /* Data-out command (e.g. WRITE) */
 #define F_D_OUT_MAYBE       4   /* WRITE SAME, NDOB bit */
 #define F_D_UNKN        8
 #define F_RL_WLUN_OK        0x10    /* allowed with REPORT LUNS W-LUN */
 #define F_SKIP_UA       0x20    /* bypass UAs (e.g. INQUIRY command) */
 #define F_DELAY_OVERR       0x40    /* for commands like INQUIRY */
 #define F_SA_LOW        0x80    /* SA is in cdb byte 1, bits 4 to 0 */
 #define F_SA_HIGH       0x100   /* SA is in cdb bytes 8 and 9 */
 #define F_INV_OP        0x200   /* invalid opcode (not supported) */
 #define F_FAKE_RW       0x400   /* bypass resp_*() when fake_rw set */
 #define F_M_ACCESS      0x800   /* media access, reacts to SSU state */
 #define F_SSU_DELAY     0x1000  /* SSU command delay (long-ish) */
 #define F_SYNC_DELAY        0x2000  /* SYNCHRONIZE CACHE delay */
 
 /* Useful combinations of the above flags */
 #define FF_RESPOND (F_RL_WLUN_OK | F_SKIP_UA | F_DELAY_OVERR)
 #define FF_MEDIA_IO (F_M_ACCESS | F_FAKE_RW)
 #define FF_SA (F_SA_HIGH | F_SA_LOW)
 #define F_LONG_DELAY        (F_SSU_DELAY | F_SYNC_DELAY)
 
 #define SDEBUG_MAX_PARTS 4
 
 #define SDEBUG_MAX_CMD_LEN 32
 
 #define SDEB_XA_NOT_IN_USE XA_MARK_1
 
 /* Zone types (zbcr05 table 25) */
 enum sdebug_z_type {
     ZBC_ZTYPE_CNV   = 0x1,
     ZBC_ZTYPE_SWR   = 0x2,
     ZBC_ZTYPE_SWP   = 0x3,
     /* ZBC_ZTYPE_SOBR = 0x4, */
     ZBC_ZTYPE_GAP   = 0x5,
 };
 
 /* enumeration names taken from table 26, zbcr05 */
 enum sdebug_z_cond {
     ZBC_NOT_WRITE_POINTER   = 0x0,
     ZC1_EMPTY       = 0x1,
     ZC2_IMPLICIT_OPEN   = 0x2,
     ZC3_EXPLICIT_OPEN   = 0x3,
     ZC4_CLOSED      = 0x4,
     ZC6_READ_ONLY       = 0xd,
     ZC5_FULL        = 0xe,
     ZC7_OFFLINE     = 0xf,
 };
 
 struct sdeb_zone_state {    /* ZBC: per zone state */
     enum sdebug_z_type z_type;
     enum sdebug_z_cond z_cond;
     bool z_non_seq_resource;
     unsigned int z_size;
     sector_t z_start;
     sector_t z_wp;
 };
 
 struct sdebug_dev_info {
     struct list_head dev_list;
     unsigned int channel;
     unsigned int target;
     u64 lun;
     uuid_t lu_name;
     struct sdebug_host_info *sdbg_host;
     unsigned long uas_bm[1];
     atomic_t num_in_q;
     atomic_t stopped;   /* 1: by SSU, 2: device start */
     bool used;
 
     /* For ZBC devices */
     enum blk_zoned_model zmodel;
     unsigned int zcap;
     unsigned int zsize;
     unsigned int zsize_shift;
     unsigned int nr_zones;
     unsigned int nr_conv_zones;
     unsigned int nr_seq_zones;
     unsigned int nr_imp_open;
     unsigned int nr_exp_open;
     unsigned int nr_closed;
     unsigned int max_open;
     ktime_t create_ts;  /* time since bootup that this device was created */
     struct sdeb_zone_state *zstate;
 };
 
 struct sdebug_host_info {
     struct list_head host_list;
     int si_idx; /* sdeb_store_info (per host) xarray index */
     struct Scsi_Host *shost;
     struct device dev;
     struct list_head dev_info_list;
 };
 
 /* There is an xarray of pointers to this struct's objects, one per host */
 struct sdeb_store_info {
     rwlock_t macc_lck;  /* for atomic media access on this store */
     u8 *storep;     /* user data storage (ram) */
     struct t10_pi_tuple *dif_storep; /* protection info */
     void *map_storep;   /* provisioning map */
 };
 
 #define to_sdebug_host(d)   \
     container_of(d, struct sdebug_host_info, dev)
 
 enum sdeb_defer_type {SDEB_DEFER_NONE = 0, SDEB_DEFER_HRT = 1,
               SDEB_DEFER_WQ = 2, SDEB_DEFER_POLL = 3};
 
 struct sdebug_defer {
     struct hrtimer hrt;
     struct execute_work ew;
     ktime_t cmpl_ts;/* time since boot to complete this cmd */
     int sqa_idx;    /* index of sdebug_queue array */
     int qc_idx; /* index of sdebug_queued_cmd array within sqa_idx */
     int hc_idx; /* hostwide tag index */
     int issuing_cpu;
     bool init_hrt;
     bool init_wq;
     bool init_poll;
     bool aborted;   /* true when blk_abort_request() already called */
     enum sdeb_defer_type defer_t;
 };
 
 struct sdebug_queued_cmd {
     /* corresponding bit set in in_use_bm[] in owning struct sdebug_queue
      * instance indicates this slot is in use.
      */
     struct sdebug_defer *sd_dp;
     struct scsi_cmnd *a_cmnd;
 };
 
 struct sdebug_queue {
     struct sdebug_queued_cmd qc_arr[SDEBUG_CANQUEUE];
     unsigned long in_use_bm[SDEBUG_CANQUEUE_WORDS];
     spinlock_t qc_lock;
     atomic_t blocked;   /* to temporarily stop more being queued */
 };
 
 static atomic_t sdebug_cmnd_count;   /* number of incoming commands */
 static atomic_t sdebug_completions;  /* count of deferred completions */
 static atomic_t sdebug_miss_cpus;    /* submission + completion cpus differ */
 static atomic_t sdebug_a_tsf;        /* 'almost task set full' counter */
 static atomic_t sdeb_inject_pending;
 static atomic_t sdeb_mq_poll_count;  /* bumped when mq_poll returns > 0 */
 
 struct opcode_info_t {
     u8 num_attached;    /* 0 if this is it (i.e. a leaf); use 0xff */
                 /* for terminating element */
     u8 opcode;      /* if num_attached > 0, preferred */
     u16 sa;         /* service action */
     u32 flags;      /* OR-ed set of SDEB_F_* */
     int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *);
     const struct opcode_info_t *arrp;  /* num_attached elements or NULL */
     u8 len_mask[16];    /* len_mask[0]-->cdb_len, then mask for cdb */
                 /* 1 to min(cdb_len, 15); ignore cdb[15...] */
 };
 
 /* SCSI opcodes (first byte of cdb) of interest mapped onto these indexes */
 enum sdeb_opcode_index {
     SDEB_I_INVALID_OPCODE = 0,
     SDEB_I_INQUIRY = 1,
     SDEB_I_REPORT_LUNS = 2,
     SDEB_I_REQUEST_SENSE = 3,
     SDEB_I_TEST_UNIT_READY = 4,
     SDEB_I_MODE_SENSE = 5,      /* 6, 10 */
     SDEB_I_MODE_SELECT = 6,     /* 6, 10 */
     SDEB_I_LOG_SENSE = 7,
     SDEB_I_READ_CAPACITY = 8,   /* 10; 16 is in SA_IN(16) */
     SDEB_I_READ = 9,        /* 6, 10, 12, 16 */
     SDEB_I_WRITE = 10,      /* 6, 10, 12, 16 */
     SDEB_I_START_STOP = 11,
     SDEB_I_SERV_ACT_IN_16 = 12, /* add ...SERV_ACT_IN_12 if needed */
     SDEB_I_SERV_ACT_OUT_16 = 13,    /* add ...SERV_ACT_OUT_12 if needed */
     SDEB_I_MAINT_IN = 14,
     SDEB_I_MAINT_OUT = 15,
     SDEB_I_VERIFY = 16,     /* VERIFY(10), VERIFY(16) */
     SDEB_I_VARIABLE_LEN = 17,   /* READ(32), WRITE(32), WR_SCAT(32) */
     SDEB_I_RESERVE = 18,        /* 6, 10 */
     SDEB_I_RELEASE = 19,        /* 6, 10 */
     SDEB_I_ALLOW_REMOVAL = 20,  /* PREVENT ALLOW MEDIUM REMOVAL */
     SDEB_I_REZERO_UNIT = 21,    /* REWIND in SSC */
     SDEB_I_ATA_PT = 22,     /* 12, 16 */
     SDEB_I_SEND_DIAG = 23,
     SDEB_I_UNMAP = 24,
     SDEB_I_WRITE_BUFFER = 25,
     SDEB_I_WRITE_SAME = 26,     /* 10, 16 */
     SDEB_I_SYNC_CACHE = 27,     /* 10, 16 */
     SDEB_I_COMP_WRITE = 28,
     SDEB_I_PRE_FETCH = 29,      /* 10, 16 */
     SDEB_I_ZONE_OUT = 30,       /* 0x94+SA; includes no data xfer */
     SDEB_I_ZONE_IN = 31,        /* 0x95+SA; all have data-in */
     SDEB_I_LAST_ELEM_P1 = 32,   /* keep this last (previous + 1) */
 };
 
 
 static const unsigned char opcode_ind_arr[256] = {
 /* 0x0; 0x0->0x1f: 6 byte cdbs */
     SDEB_I_TEST_UNIT_READY, SDEB_I_REZERO_UNIT, 0, SDEB_I_REQUEST_SENSE,
         0, 0, 0, 0,
     SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, 0,
     0, 0, SDEB_I_INQUIRY, 0, 0, SDEB_I_MODE_SELECT, SDEB_I_RESERVE,
         SDEB_I_RELEASE,
     0, 0, SDEB_I_MODE_SENSE, SDEB_I_START_STOP, 0, SDEB_I_SEND_DIAG,
         SDEB_I_ALLOW_REMOVAL, 0,
 /* 0x20; 0x20->0x3f: 10 byte cdbs */
     0, 0, 0, 0, 0, SDEB_I_READ_CAPACITY, 0, 0,
     SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, SDEB_I_VERIFY,
     0, 0, 0, 0, SDEB_I_PRE_FETCH, SDEB_I_SYNC_CACHE, 0, 0,
     0, 0, 0, SDEB_I_WRITE_BUFFER, 0, 0, 0, 0,
 /* 0x40; 0x40->0x5f: 10 byte cdbs */
     0, SDEB_I_WRITE_SAME, SDEB_I_UNMAP, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, SDEB_I_LOG_SENSE, 0, 0,
     0, 0, 0, 0, 0, SDEB_I_MODE_SELECT, SDEB_I_RESERVE,
         SDEB_I_RELEASE,
     0, 0, SDEB_I_MODE_SENSE, 0, 0, 0, 0, 0,
 /* 0x60; 0x60->0x7d are reserved, 0x7e is "extended cdb" */
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, SDEB_I_VARIABLE_LEN,
 /* 0x80; 0x80->0x9f: 16 byte cdbs */
     0, 0, 0, 0, 0, SDEB_I_ATA_PT, 0, 0,
     SDEB_I_READ, SDEB_I_COMP_WRITE, SDEB_I_WRITE, 0,
     0, 0, 0, SDEB_I_VERIFY,
     SDEB_I_PRE_FETCH, SDEB_I_SYNC_CACHE, 0, SDEB_I_WRITE_SAME,
     SDEB_I_ZONE_OUT, SDEB_I_ZONE_IN, 0, 0,
     0, 0, 0, 0, 0, 0, SDEB_I_SERV_ACT_IN_16, SDEB_I_SERV_ACT_OUT_16,
 /* 0xa0; 0xa0->0xbf: 12 byte cdbs */
     SDEB_I_REPORT_LUNS, SDEB_I_ATA_PT, 0, SDEB_I_MAINT_IN,
          SDEB_I_MAINT_OUT, 0, 0, 0,
     SDEB_I_READ, 0 /* SDEB_I_SERV_ACT_OUT_12 */, SDEB_I_WRITE,
          0 /* SDEB_I_SERV_ACT_IN_12 */, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0,
 /* 0xc0; 0xc0->0xff: vendor specific */
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 };
 
 /*
  * The following "response" functions return the SCSI mid-level's 4 byte
  * tuple-in-an-int. To handle commands with an IMMED bit, for a faster
  * command completion, they can mask their return value with
  * SDEG_RES_IMMED_MASK .
  */
 #define SDEG_RES_IMMED_MASK 0x40000000
 
 static int resp_inquiry(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_report_luns(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_requests(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_mode_sense(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_mode_select(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_log_sense(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_readcap(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_read_dt0(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_write_dt0(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_write_scat(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_start_stop(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_readcap16(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_get_lba_status(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_report_tgtpgs(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_unmap(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_rsup_opcodes(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_rsup_tmfs(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_verify(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_write_same_10(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_write_same_16(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_comp_write(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_write_buffer(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_sync_cache(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_pre_fetch(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_report_zones(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_open_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_close_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_finish_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_rwp_zone(struct scsi_cmnd *, struct sdebug_dev_info *);
 
 static int sdebug_do_add_host(bool mk_new_store);
 static int sdebug_add_host_helper(int per_host_idx);
 static void sdebug_do_remove_host(bool the_end);
 static int sdebug_add_store(void);
 static void sdebug_erase_store(int idx, struct sdeb_store_info *sip);
 static void sdebug_erase_all_stores(bool apart_from_first);
 
 /*
  * The following are overflow arrays for cdbs that "hit" the same index in
  * the opcode_info_arr array. The most time sensitive (or commonly used) cdb
  * should be placed in opcode_info_arr[], the others should be placed here.
  */
 static const struct opcode_info_t msense_iarr[] = {
     {0, 0x1a, 0, F_D_IN, NULL, NULL,
         {6,  0xe8, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t mselect_iarr[] = {
     {0, 0x15, 0, F_D_OUT, NULL, NULL,
         {6,  0xf1, 0, 0, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t read_iarr[] = {
     {0, 0x28, 0, F_D_IN | FF_MEDIA_IO, resp_read_dt0, NULL,/* READ(10) */
         {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
          0, 0, 0, 0} },
     {0, 0x8, 0, F_D_IN | FF_MEDIA_IO, resp_read_dt0, NULL, /* READ(6) */
         {6,  0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0xa8, 0, F_D_IN | FF_MEDIA_IO, resp_read_dt0, NULL,/* READ(12) */
         {12,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xbf,
          0xc7, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t write_iarr[] = {
     {0, 0x2a, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,  /* WRITE(10) */
         NULL, {10,  0xfb, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7,
            0, 0, 0, 0, 0, 0} },
     {0, 0xa, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,   /* WRITE(6) */
         NULL, {6,  0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0} },
     {0, 0xaa, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,  /* WRITE(12) */
         NULL, {12,  0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
            0xbf, 0xc7, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t verify_iarr[] = {
     {0, 0x2f, 0, F_D_OUT_MAYBE | FF_MEDIA_IO, resp_verify,/* VERIFY(10) */
         NULL, {10,  0xf7, 0xff, 0xff, 0xff, 0xff, 0xbf, 0xff, 0xff, 0xc7,
            0, 0, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t sa_in_16_iarr[] = {
     {0, 0x9e, 0x12, F_SA_LOW | F_D_IN, resp_get_lba_status, NULL,
         {16,  0x12, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0, 0xc7} },  /* GET LBA STATUS(16) */
 };
 
 static const struct opcode_info_t vl_iarr[] = { /* VARIABLE LENGTH */
     {0, 0x7f, 0xb, F_SA_HIGH | F_D_OUT | FF_MEDIA_IO, resp_write_dt0,
         NULL, {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0xb, 0xfa,
            0, 0xff, 0xff, 0xff, 0xff} },    /* WRITE(32) */
     {0, 0x7f, 0x11, F_SA_HIGH | F_D_OUT | FF_MEDIA_IO, resp_write_scat,
         NULL, {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0x11, 0xf8,
            0, 0xff, 0xff, 0x0, 0x0} },  /* WRITE SCATTERED(32) */
 };
 
 static const struct opcode_info_t maint_in_iarr[] = {   /* MAINT IN */
     {0, 0xa3, 0xc, F_SA_LOW | F_D_IN, resp_rsup_opcodes, NULL,
         {12,  0xc, 0x87, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0,
          0xc7, 0, 0, 0, 0} }, /* REPORT SUPPORTED OPERATION CODES */
     {0, 0xa3, 0xd, F_SA_LOW | F_D_IN, resp_rsup_tmfs, NULL,
         {12,  0xd, 0x80, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0,
          0, 0} },   /* REPORTED SUPPORTED TASK MANAGEMENT FUNCTIONS */
 };
 
 static const struct opcode_info_t write_same_iarr[] = {
     {0, 0x93, 0, F_D_OUT_MAYBE | FF_MEDIA_IO, resp_write_same_16, NULL,
         {16,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0x3f, 0xc7} },       /* WRITE SAME(16) */
 };
 
 static const struct opcode_info_t reserve_iarr[] = {
     {0, 0x16, 0, F_D_OUT, NULL, NULL,       /* RESERVE(6) */
         {6,  0x1f, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t release_iarr[] = {
     {0, 0x17, 0, F_D_OUT, NULL, NULL,       /* RELEASE(6) */
         {6,  0x1f, 0xff, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
 static const struct opcode_info_t sync_cache_iarr[] = {
     {0, 0x91, 0, F_SYNC_DELAY | F_M_ACCESS, resp_sync_cache, NULL,
         {16,  0x6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0x3f, 0xc7} }, /* SYNC_CACHE (16) */
 };
 
 static const struct opcode_info_t pre_fetch_iarr[] = {
     {0, 0x90, 0, F_SYNC_DELAY | FF_MEDIA_IO, resp_pre_fetch, NULL,
         {16,  0x2, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0x3f, 0xc7} }, /* PRE-FETCH (16) */
 };
 
 static const struct opcode_info_t zone_out_iarr[] = {   /* ZONE OUT(16) */
     {0, 0x94, 0x1, F_SA_LOW | F_M_ACCESS, resp_close_zone, NULL,
         {16, 0x1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0, 0, 0xff, 0xff, 0x1, 0xc7} },  /* CLOSE ZONE */
     {0, 0x94, 0x2, F_SA_LOW | F_M_ACCESS, resp_finish_zone, NULL,
         {16, 0x2, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0, 0, 0xff, 0xff, 0x1, 0xc7} },  /* FINISH ZONE */
     {0, 0x94, 0x4, F_SA_LOW | F_M_ACCESS, resp_rwp_zone, NULL,
         {16, 0x4, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0, 0, 0xff, 0xff, 0x1, 0xc7} },  /* RESET WRITE POINTER */
 };
 
 static const struct opcode_info_t zone_in_iarr[] = {    /* ZONE IN(16) */
     {0, 0x95, 0x6, F_SA_LOW | F_D_IN | F_M_ACCESS, NULL, NULL,
         {16, 0x6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0x3f, 0xc7} }, /* REPORT ZONES */
 };
 
 
 /* This array is accessed via SDEB_I_* values. Make sure all are mapped,
  * plus the terminating elements for logic that scans this table such as
  * REPORT SUPPORTED OPERATION CODES. */
 static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEM_P1 + 1] = {
 /* 0 */
     {0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL,    /* unknown opcodes */
         {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0x12, 0, FF_RESPOND | F_D_IN, resp_inquiry, NULL, /* INQUIRY */
         {6,  0xe3, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0xa0, 0, FF_RESPOND | F_D_IN, resp_report_luns, NULL,
         {12,  0xe3, 0xff, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0,
          0, 0} },                   /* REPORT LUNS */
     {0, 0x3, 0, FF_RESPOND | F_D_IN, resp_requests, NULL,
         {6,  0xe1, 0, 0, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0x0, 0, F_M_ACCESS | F_RL_WLUN_OK, NULL, NULL,/* TEST UNIT READY */
         {6,  0, 0, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 /* 5 */
     {ARRAY_SIZE(msense_iarr), 0x5a, 0, F_D_IN,  /* MODE SENSE(10) */
         resp_mode_sense, msense_iarr, {10,  0xf8, 0xff, 0xff, 0, 0, 0,
         0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
     {ARRAY_SIZE(mselect_iarr), 0x55, 0, F_D_OUT,    /* MODE SELECT(10) */
         resp_mode_select, mselect_iarr, {10,  0xf1, 0, 0, 0, 0, 0, 0xff,
         0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
     {0, 0x4d, 0, F_D_IN, resp_log_sense, NULL,  /* LOG SENSE */
         {10,  0xe3, 0xff, 0xff, 0, 0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0,
          0, 0, 0} },
     {0, 0x25, 0, F_D_IN, resp_readcap, NULL,    /* READ CAPACITY(10) */
         {10,  0xe1, 0xff, 0xff, 0xff, 0xff, 0, 0, 0x1, 0xc7, 0, 0, 0, 0,
          0, 0} },
     {ARRAY_SIZE(read_iarr), 0x88, 0, F_D_IN | FF_MEDIA_IO, /* READ(16) */
         resp_read_dt0, read_iarr, {16,  0xfe, 0xff, 0xff, 0xff, 0xff,
         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7} },
 /* 10 */
     {ARRAY_SIZE(write_iarr), 0x8a, 0, F_D_OUT | FF_MEDIA_IO,
         resp_write_dt0, write_iarr,         /* WRITE(16) */
         {16,  0xfa, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0xff, 0xc7} },
     {0, 0x1b, 0, F_SSU_DELAY, resp_start_stop, NULL,/* START STOP UNIT */
         {6,  0x1, 0, 0xf, 0xf7, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {ARRAY_SIZE(sa_in_16_iarr), 0x9e, 0x10, F_SA_LOW | F_D_IN,
         resp_readcap16, sa_in_16_iarr, /* SA_IN(16), READ CAPACITY(16) */
         {16,  0x10, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0x1, 0xc7} },
     {0, 0x9f, 0x12, F_SA_LOW | F_D_OUT | FF_MEDIA_IO, resp_write_scat,
         NULL, {16,  0x12, 0xf9, 0x0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff,
         0xff, 0xff, 0xff, 0xff, 0xc7} },  /* SA_OUT(16), WRITE SCAT(16) */
     {ARRAY_SIZE(maint_in_iarr), 0xa3, 0xa, F_SA_LOW | F_D_IN,
         resp_report_tgtpgs, /* MAINT IN, REPORT TARGET PORT GROUPS */
         maint_in_iarr, {12,  0xea, 0, 0, 0, 0, 0xff, 0xff, 0xff,
                 0xff, 0, 0xc7, 0, 0, 0, 0} },
 /* 15 */
     {0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* MAINT OUT */
         {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {ARRAY_SIZE(verify_iarr), 0x8f, 0,
         F_D_OUT_MAYBE | FF_MEDIA_IO, resp_verify,   /* VERIFY(16) */
         verify_iarr, {16,  0xf6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
               0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xc7} },
     {ARRAY_SIZE(vl_iarr), 0x7f, 0x9, F_SA_HIGH | F_D_IN | FF_MEDIA_IO,
         resp_read_dt0, vl_iarr, /* VARIABLE LENGTH, READ(32) */
         {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0x9, 0xfe, 0, 0xff, 0xff,
          0xff, 0xff} },
     {ARRAY_SIZE(reserve_iarr), 0x56, 0, F_D_OUT,
         NULL, reserve_iarr, /* RESERVE(10) <no response function> */
         {10,  0xff, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
          0} },
     {ARRAY_SIZE(release_iarr), 0x57, 0, F_D_OUT,
         NULL, release_iarr, /* RELEASE(10) <no response function> */
         {10,  0x13, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
          0} },
 /* 20 */
     {0, 0x1e, 0, 0, NULL, NULL, /* ALLOW REMOVAL */
         {6,  0, 0, 0, 0x3, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0x1, 0, 0, resp_start_stop, NULL, /* REWIND ?? */
         {6,  0x1, 0, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* ATA_PT */
         {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0x1d, F_D_OUT, 0, NULL, NULL,   /* SEND DIAGNOSTIC */
         {6,  0xf7, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
     {0, 0x42, 0, F_D_OUT | FF_MEDIA_IO, resp_unmap, NULL, /* UNMAP */
         {10,  0x1, 0, 0, 0, 0, 0x3f, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
 /* 25 */
     {0, 0x3b, 0, F_D_OUT_MAYBE, resp_write_buffer, NULL,
         {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0,
          0, 0, 0, 0} },         /* WRITE_BUFFER */
     {ARRAY_SIZE(write_same_iarr), 0x41, 0, F_D_OUT_MAYBE | FF_MEDIA_IO,
         resp_write_same_10, write_same_iarr,    /* WRITE SAME(10) */
         {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0,
          0, 0, 0, 0, 0} },
     {ARRAY_SIZE(sync_cache_iarr), 0x35, 0, F_SYNC_DELAY | F_M_ACCESS,
         resp_sync_cache, sync_cache_iarr,
         {10,  0x7, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
          0, 0, 0, 0} },         /* SYNC_CACHE (10) */
     {0, 0x89, 0, F_D_OUT | FF_MEDIA_IO, resp_comp_write, NULL,
         {16,  0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0,
          0, 0xff, 0x3f, 0xc7} },        /* COMPARE AND WRITE */
     {ARRAY_SIZE(pre_fetch_iarr), 0x34, 0, F_SYNC_DELAY | FF_MEDIA_IO,
         resp_pre_fetch, pre_fetch_iarr,
         {10,  0x2, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
          0, 0, 0, 0} },         /* PRE-FETCH (10) */
 
 /* 30 */
     {ARRAY_SIZE(zone_out_iarr), 0x94, 0x3, F_SA_LOW | F_M_ACCESS,
         resp_open_zone, zone_out_iarr, /* ZONE_OUT(16), OPEN ZONE) */
         {16,  0x3 /* SA */, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0x0, 0x0, 0xff, 0xff, 0x1, 0xc7} },
     {ARRAY_SIZE(zone_in_iarr), 0x95, 0x0, F_SA_LOW | F_M_ACCESS,
         resp_report_zones, zone_in_iarr, /* ZONE_IN(16), REPORT ZONES) */
         {16,  0x0 /* SA */, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xbf, 0xc7} },
 /* sentinel */
     {0xff, 0, 0, 0, NULL, NULL,     /* terminating element */
         {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
 static int sdebug_num_hosts;
 static int sdebug_add_host = DEF_NUM_HOST;  /* in sysfs this is relative */
 static int sdebug_ato = DEF_ATO;
 static int sdebug_cdb_len = DEF_CDB_LEN;
 static int sdebug_jdelay = DEF_JDELAY;  /* if > 0 then unit is jiffies */
 static int sdebug_dev_size_mb = DEF_DEV_SIZE_PRE_INIT;
 static int sdebug_dif = DEF_DIF;
 static int sdebug_dix = DEF_DIX;
 static int sdebug_dsense = DEF_D_SENSE;
 static int sdebug_every_nth = DEF_EVERY_NTH;
 static int sdebug_fake_rw = DEF_FAKE_RW;
 static unsigned int sdebug_guard = DEF_GUARD;
 static int sdebug_host_max_queue;   /* per host */
 static int sdebug_lowest_aligned = DEF_LOWEST_ALIGNED;
 static int sdebug_max_luns = DEF_MAX_LUNS;
 static int sdebug_max_queue = SDEBUG_CANQUEUE;  /* per submit queue */
 static unsigned int sdebug_medium_error_start = OPT_MEDIUM_ERR_ADDR;
 static int sdebug_medium_error_count = OPT_MEDIUM_ERR_NUM;
 static atomic_t retired_max_queue;  /* if > 0 then was prior max_queue */
 static int sdebug_ndelay = DEF_NDELAY;  /* if > 0 then unit is nanoseconds */
 static int sdebug_no_lun_0 = DEF_NO_LUN_0;
 static int sdebug_no_uld;
 static int sdebug_num_parts = DEF_NUM_PARTS;
 static int sdebug_num_tgts = DEF_NUM_TGTS; /* targets per host */
 static int sdebug_opt_blks = DEF_OPT_BLKS;
 static int sdebug_opts = DEF_OPTS;
 static int sdebug_physblk_exp = DEF_PHYSBLK_EXP;
 static int sdebug_opt_xferlen_exp = DEF_OPT_XFERLEN_EXP;
 static int sdebug_ptype = DEF_PTYPE; /* SCSI peripheral device type */
 static int sdebug_scsi_level = DEF_SCSI_LEVEL;
 static int sdebug_sector_size = DEF_SECTOR_SIZE;
 static int sdeb_tur_ms_to_ready = DEF_TUR_MS_TO_READY;
 static int sdebug_virtual_gb = DEF_VIRTUAL_GB;
 static int sdebug_vpd_use_hostno = DEF_VPD_USE_HOSTNO;
 static unsigned int sdebug_lbpu = DEF_LBPU;
 static unsigned int sdebug_lbpws = DEF_LBPWS;
 static unsigned int sdebug_lbpws10 = DEF_LBPWS10;
 static unsigned int sdebug_lbprz = DEF_LBPRZ;
 static unsigned int sdebug_unmap_alignment = DEF_UNMAP_ALIGNMENT;
 static unsigned int sdebug_unmap_granularity = DEF_UNMAP_GRANULARITY;
 static unsigned int sdebug_unmap_max_blocks = DEF_UNMAP_MAX_BLOCKS;
 static unsigned int sdebug_unmap_max_desc = DEF_UNMAP_MAX_DESC;
 static unsigned int sdebug_write_same_length = DEF_WRITESAME_LENGTH;
 static int sdebug_uuid_ctl = DEF_UUID_CTL;
 static bool sdebug_random = DEF_RANDOM;
 static bool sdebug_per_host_store = DEF_PER_HOST_STORE;
 static bool sdebug_removable = DEF_REMOVABLE;
 static bool sdebug_clustering;
 static bool sdebug_host_lock = DEF_HOST_LOCK;
 static bool sdebug_strict = DEF_STRICT;
 static bool sdebug_any_injecting_opt;
 static bool sdebug_no_rwlock;
 static bool sdebug_verbose;
 static bool have_dif_prot;
 static bool write_since_sync;
 static bool sdebug_statistics = DEF_STATISTICS;
 static bool sdebug_wp;
 /* Following enum: 0: no zbc, def; 1: host aware; 2: host managed */
 static enum blk_zoned_model sdeb_zbc_model = BLK_ZONED_NONE;
 static char *sdeb_zbc_model_s;
 
 enum sam_lun_addr_method {SAM_LUN_AM_PERIPHERAL = 0x0,
               SAM_LUN_AM_FLAT = 0x1,
               SAM_LUN_AM_LOGICAL_UNIT = 0x2,
               SAM_LUN_AM_EXTENDED = 0x3};
 static enum sam_lun_addr_method sdebug_lun_am = SAM_LUN_AM_PERIPHERAL;
 static int sdebug_lun_am_i = (int)SAM_LUN_AM_PERIPHERAL;
 
 static unsigned int sdebug_store_sectors;
 static sector_t sdebug_capacity;    /* in sectors */
 
 /* old BIOS stuff, kernel may get rid of them but some mode sense pages
    may still need them */
 static int sdebug_heads;        /* heads per disk */
 static int sdebug_cylinders_per;    /* cylinders per surface */
 static int sdebug_sectors_per;      /* sectors per cylinder */
 
 static LIST_HEAD(sdebug_host_list);
 static DEFINE_SPINLOCK(sdebug_host_list_lock);
 
 static struct xarray per_store_arr;
 static struct xarray *per_store_ap = &per_store_arr;
 static int sdeb_first_idx = -1;     /* invalid index ==> none created */
 static int sdeb_most_recent_idx = -1;
 static DEFINE_RWLOCK(sdeb_fake_rw_lck); /* need a RW lock when fake_rw=1 */
 
 static unsigned long map_size;
 static int num_aborts;
 static int num_dev_resets;
 static int num_target_resets;
 static int num_bus_resets;
 static int num_host_resets;
 static int dix_writes;
 static int dix_reads;
 static int dif_errors;
 
 /* ZBC global data */
 static bool sdeb_zbc_in_use;    /* true for host-aware and host-managed disks */
 static int sdeb_zbc_zone_cap_mb;
 static int sdeb_zbc_zone_size_mb;
 static int sdeb_zbc_max_open = DEF_ZBC_MAX_OPEN_ZONES;
 static int sdeb_zbc_nr_conv = DEF_ZBC_NR_CONV_ZONES;
 
 static int submit_queues = DEF_SUBMIT_QUEUES;  /* > 1 for multi-queue (mq) */
 static int poll_queues; /* iouring iopoll interface.*/
 static struct sdebug_queue *sdebug_q_arr;  /* ptr to array of submit queues */
 
 static DEFINE_RWLOCK(atomic_rw);
 static DEFINE_RWLOCK(atomic_rw2);
 
 static rwlock_t *ramdisk_lck_a[2];
 
 static char sdebug_proc_name[] = MY_NAME;
 static const char *my_name = MY_NAME;
 
 static struct bus_type pseudo_lld_bus;
 
 static struct device_driver sdebug_driverfs_driver = {
     .name       = sdebug_proc_name,
     .bus        = &pseudo_lld_bus,
 };
 
 static const int check_condition_result =
     SAM_STAT_CHECK_CONDITION;
 
 static const int illegal_condition_result =
     (DID_ABORT << 16) | SAM_STAT_CHECK_CONDITION;
 
 static const int device_qfull_result =
     (DID_ABORT << 16) | SAM_STAT_TASK_SET_FULL;
 
 static const int condition_met_result = SAM_STAT_CONDITION_MET;
 
 
 /* Only do the extra work involved in logical block provisioning if one or
  * more of the lbpu, lbpws or lbpws10 parameters are given and we are doing
  * real reads and writes (i.e. not skipping them for speed).
  */
 static inline bool scsi_debug_lbp(void)
 {
     return 0 == sdebug_fake_rw &&
         (sdebug_lbpu || sdebug_lbpws || sdebug_lbpws10);
 }
 
 static void *lba2fake_store(struct sdeb_store_info *sip,
                 unsigned long long lba)
 {
     struct sdeb_store_info *lsip = sip;
 
     lba = do_div(lba, sdebug_store_sectors);
     if (!sip || !sip->storep) {
         WARN_ON_ONCE(true);
         lsip = xa_load(per_store_ap, 0);  /* should never be NULL */
     }
     return lsip->storep + lba * sdebug_sector_size;
 }
 
 static struct t10_pi_tuple *dif_store(struct sdeb_store_info *sip,
                       sector_t sector)
 {
     sector = sector_div(sector, sdebug_store_sectors);
 
     return sip->dif_storep + sector;
 }
 
 static void sdebug_max_tgts_luns(void)
 {
     struct sdebug_host_info *sdbg_host;
     struct Scsi_Host *hpnt;
 
     spin_lock(&sdebug_host_list_lock);
     list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
         hpnt = sdbg_host->shost;
         if ((hpnt->this_id >= 0) &&
             (sdebug_num_tgts > hpnt->this_id))
             hpnt->max_id = sdebug_num_tgts + 1;
         else
             hpnt->max_id = sdebug_num_tgts;
         /* sdebug_max_luns; */
         hpnt->max_lun = SCSI_W_LUN_REPORT_LUNS + 1;
     }
     spin_unlock(&sdebug_host_list_lock);
 }
 
 enum sdeb_cmd_data {SDEB_IN_DATA = 0, SDEB_IN_CDB = 1};
 
 /* Set in_bit to -1 to indicate no bit position of invalid field */
 static void mk_sense_invalid_fld(struct scsi_cmnd *scp,
                  enum sdeb_cmd_data c_d,
                  int in_byte, int in_bit)
 {
     unsigned char *sbuff;
     u8 sks[4];
     int sl, asc;
 
     sbuff = scp->sense_buffer;
     if (!sbuff) {
         sdev_printk(KERN_ERR, scp->device,
                 "%s: sense_buffer is NULL\n", __func__);
         return;
     }
     asc = c_d ? INVALID_FIELD_IN_CDB : INVALID_FIELD_IN_PARAM_LIST;
     memset(sbuff, 0, SCSI_SENSE_BUFFERSIZE);
     scsi_build_sense(scp, sdebug_dsense, ILLEGAL_REQUEST, asc, 0);
     memset(sks, 0, sizeof(sks));
     sks[0] = 0x80;
     if (c_d)
         sks[0] |= 0x40;
     if (in_bit >= 0) {
         sks[0] |= 0x8;
         sks[0] |= 0x7 & in_bit;
     }
     put_unaligned_be16(in_byte, sks + 1);
     if (sdebug_dsense) {
         sl = sbuff[7] + 8;
         sbuff[7] = sl;
         sbuff[sl] = 0x2;
         sbuff[sl + 1] = 0x6;
         memcpy(sbuff + sl + 4, sks, 3);
     } else
         memcpy(sbuff + 15, sks, 3);
     if (sdebug_verbose)
         sdev_printk(KERN_INFO, scp->device, "%s:  [sense_key,asc,ascq"
                 "]: [0x5,0x%x,0x0] %c byte=%d, bit=%d\n",
                 my_name, asc, c_d ? 'C' : 'D', in_byte, in_bit);
 }
 
 static void mk_sense_buffer(struct scsi_cmnd *scp, int key, int asc, int asq)
 {
     if (!scp->sense_buffer) {
         sdev_printk(KERN_ERR, scp->device,
                 "%s: sense_buffer is NULL\n", __func__);
         return;
     }
     memset(scp->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
 
     scsi_build_sense(scp, sdebug_dsense, key, asc, asq);
 
     if (sdebug_verbose)
         sdev_printk(KERN_INFO, scp->device,
                 "%s:  [sense_key,asc,ascq]: [0x%x,0x%x,0x%x]\n",
                 my_name, key, asc, asq);
 }
 
 static void mk_sense_invalid_opcode(struct scsi_cmnd *scp)
 {
     mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_OPCODE, 0);
 }
 
 static int scsi_debug_ioctl(struct scsi_device *dev, unsigned int cmd,
                 void __user *arg)
 {
     if (sdebug_verbose) {
         if (0x1261 == cmd)
             sdev_printk(KERN_INFO, dev,
                     "%s: BLKFLSBUF [0x1261]\n", __func__);
         else if (0x5331 == cmd)
             sdev_printk(KERN_INFO, dev,
                     "%s: CDROM_GET_CAPABILITY [0x5331]\n",
                     __func__);
         else
             sdev_printk(KERN_INFO, dev, "%s: cmd=0x%x\n",
                     __func__, cmd);
     }
     return -EINVAL;
     /* return -ENOTTY; // correct return but upsets fdisk */
 }
 
 static void config_cdb_len(struct scsi_device *sdev)
 {
     switch (sdebug_cdb_len) {
     case 6: /* suggest 6 byte READ, WRITE and MODE SENSE/SELECT */
         sdev->use_10_for_rw = false;
         sdev->use_16_for_rw = false;
         sdev->use_10_for_ms = false;
         break;
     case 10: /* suggest 10 byte RWs and 6 byte MODE SENSE/SELECT */
         sdev->use_10_for_rw = true;
         sdev->use_16_for_rw = false;
         sdev->use_10_for_ms = false;
         break;
     case 12: /* suggest 10 byte RWs and 10 byte MODE SENSE/SELECT */
         sdev->use_10_for_rw = true;
         sdev->use_16_for_rw = false;
         sdev->use_10_for_ms = true;
         break;
     case 16:
         sdev->use_10_for_rw = false;
         sdev->use_16_for_rw = true;
         sdev->use_10_for_ms = true;
         break;
     case 32: /* No knobs to suggest this so same as 16 for now */
         sdev->use_10_for_rw = false;
         sdev->use_16_for_rw = true;
         sdev->use_10_for_ms = true;
         break;
     default:
         pr_warn("unexpected cdb_len=%d, force to 10\n",
             sdebug_cdb_len);
         sdev->use_10_for_rw = true;
         sdev->use_16_for_rw = false;
         sdev->use_10_for_ms = false;
         sdebug_cdb_len = 10;
         break;
     }
 }
 
 static void all_config_cdb_len(void)
 {
     struct sdebug_host_info *sdbg_host;
     struct Scsi_Host *shost;
     struct scsi_device *sdev;
 
     spin_lock(&sdebug_host_list_lock);
     list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
         shost = sdbg_host->shost;
         shost_for_each_device(sdev, shost) {
             config_cdb_len(sdev);
         }
     }
     spin_unlock(&sdebug_host_list_lock);
 }
 
 static void clear_luns_changed_on_target(struct sdebug_dev_info *devip)
 {
     struct sdebug_host_info *sdhp;
     struct sdebug_dev_info *dp;
 
     spin_lock(&sdebug_host_list_lock);
     list_for_each_entry(sdhp, &sdebug_host_list, host_list) {
         list_for_each_entry(dp, &sdhp->dev_info_list, dev_list) {
             if ((devip->sdbg_host == dp->sdbg_host) &&
                 (devip->target == dp->target))
                 clear_bit(SDEBUG_UA_LUNS_CHANGED, dp->uas_bm);
         }
     }
     spin_unlock(&sdebug_host_list_lock);
 }
 
 static int make_ua(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     int k;
 
     k = find_first_bit(devip->uas_bm, SDEBUG_NUM_UAS);
     if (k != SDEBUG_NUM_UAS) {
         const char *cp = NULL;
 
         switch (k) {
         case SDEBUG_UA_POR:
             mk_sense_buffer(scp, UNIT_ATTENTION, UA_RESET_ASC,
                     POWER_ON_RESET_ASCQ);
             if (sdebug_verbose)
                 cp = "power on reset";
             break;
         case SDEBUG_UA_POOCCUR:
             mk_sense_buffer(scp, UNIT_ATTENTION, UA_RESET_ASC,
                     POWER_ON_OCCURRED_ASCQ);
             if (sdebug_verbose)
                 cp = "power on occurred";
             break;
         case SDEBUG_UA_BUS_RESET:
             mk_sense_buffer(scp, UNIT_ATTENTION, UA_RESET_ASC,
                     BUS_RESET_ASCQ);
             if (sdebug_verbose)
                 cp = "bus reset";
             break;
         case SDEBUG_UA_MODE_CHANGED:
             mk_sense_buffer(scp, UNIT_ATTENTION, UA_CHANGED_ASC,
                     MODE_CHANGED_ASCQ);
             if (sdebug_verbose)
                 cp = "mode parameters changed";
             break;
         case SDEBUG_UA_CAPACITY_CHANGED:
             mk_sense_buffer(scp, UNIT_ATTENTION, UA_CHANGED_ASC,
                     CAPACITY_CHANGED_ASCQ);
             if (sdebug_verbose)
                 cp = "capacity data changed";
             break;
         case SDEBUG_UA_MICROCODE_CHANGED:
             mk_sense_buffer(scp, UNIT_ATTENTION,
                     TARGET_CHANGED_ASC,
                     MICROCODE_CHANGED_ASCQ);
             if (sdebug_verbose)
                 cp = "microcode has been changed";
             break;
         case SDEBUG_UA_MICROCODE_CHANGED_WO_RESET:
             mk_sense_buffer(scp, UNIT_ATTENTION,
                     TARGET_CHANGED_ASC,
                     MICROCODE_CHANGED_WO_RESET_ASCQ);
             if (sdebug_verbose)
                 cp = "microcode has been changed without reset";
             break;
         case SDEBUG_UA_LUNS_CHANGED:
             /*
              * SPC-3 behavior is to report a UNIT ATTENTION with
              * ASC/ASCQ REPORTED LUNS DATA HAS CHANGED on every LUN
              * on the target, until a REPORT LUNS command is
              * received.  SPC-4 behavior is to report it only once.
              * NOTE:  sdebug_scsi_level does not use the same
              * values as struct scsi_device->scsi_level.
              */
             if (sdebug_scsi_level >= 6) /* SPC-4 and above */
                 clear_luns_changed_on_target(devip);
             mk_sense_buffer(scp, UNIT_ATTENTION,
                     TARGET_CHANGED_ASC,
                     LUNS_CHANGED_ASCQ);
             if (sdebug_verbose)
                 cp = "reported luns data has changed";
             break;
         default:
             pr_warn("unexpected unit attention code=%d\n", k);
             if (sdebug_verbose)
                 cp = "unknown";
             break;
         }
         clear_bit(k, devip->uas_bm);
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, scp->device,
                    "%s reports: Unit attention: %s\n",
                    my_name, cp);
         return check_condition_result;
     }
     return 0;
 }
 
 /* Build SCSI "data-in" buffer. Returns 0 if ok else (DID_ERROR << 16). */
 static int fill_from_dev_buffer(struct scsi_cmnd *scp, unsigned char *arr,
                 int arr_len)
 {
     int act_len;
     struct scsi_data_buffer *sdb = &scp->sdb;
 
     if (!sdb->length)
         return 0;
     if (scp->sc_data_direction != DMA_FROM_DEVICE)
         return DID_ERROR << 16;
 
     act_len = sg_copy_from_buffer(sdb->table.sgl, sdb->table.nents,
                       arr, arr_len);
     scsi_set_resid(scp, scsi_bufflen(scp) - act_len);
 
     return 0;
 }
 
 /* Partial build of SCSI "data-in" buffer. Returns 0 if ok else
  * (DID_ERROR << 16). Can write to offset in data-in buffer. If multiple
  * calls, not required to write in ascending offset order. Assumes resid
  * set to scsi_bufflen() prior to any calls.
  */
 static int p_fill_from_dev_buffer(struct scsi_cmnd *scp, const void *arr,
                   int arr_len, unsigned int off_dst)
 {
     unsigned int act_len, n;
     struct scsi_data_buffer *sdb = &scp->sdb;
     off_t skip = off_dst;
 
     if (sdb->length <= off_dst)
         return 0;
     if (scp->sc_data_direction != DMA_FROM_DEVICE)
         return DID_ERROR << 16;
 
     act_len = sg_pcopy_from_buffer(sdb->table.sgl, sdb->table.nents,
                        arr, arr_len, skip);
     pr_debug("%s: off_dst=%u, scsi_bufflen=%u, act_len=%u, resid=%d\n",
          __func__, off_dst, scsi_bufflen(scp), act_len,
          scsi_get_resid(scp));
     n = scsi_bufflen(scp) - (off_dst + act_len);
     scsi_set_resid(scp, min_t(u32, scsi_get_resid(scp), n));
     return 0;
 }
 
 /* Fetches from SCSI "data-out" buffer. Returns number of bytes fetched into
  * 'arr' or -1 if error.
  */
 static int fetch_to_dev_buffer(struct scsi_cmnd *scp, unsigned char *arr,
                    int arr_len)
 {
     if (!scsi_bufflen(scp))
         return 0;
     if (scp->sc_data_direction != DMA_TO_DEVICE)
         return -1;
 
     return scsi_sg_copy_to_buffer(scp, arr, arr_len);
 }
 
 
 static char sdebug_inq_vendor_id[9] = "Linux   ";
 static char sdebug_inq_product_id[17] = "scsi_debug      ";
 static char sdebug_inq_product_rev[5] = SDEBUG_VERSION;
 /* Use some locally assigned NAAs for SAS addresses. */
 static const u64 naa3_comp_a = 0x3222222000000000ULL;
 static const u64 naa3_comp_b = 0x3333333000000000ULL;
 static const u64 naa3_comp_c = 0x3111111000000000ULL;
 
 /* Device identification VPD page. Returns number of bytes placed in arr */
 static int inquiry_vpd_83(unsigned char *arr, int port_group_id,
               int target_dev_id, int dev_id_num,
               const char *dev_id_str, int dev_id_str_len,
               const uuid_t *lu_name)
 {
     int num, port_a;
     char b[32];
 
     port_a = target_dev_id + 1;
     /* T10 vendor identifier field format (faked) */
     arr[0] = 0x2;   /* ASCII */
     arr[1] = 0x1;
     arr[2] = 0x0;
     memcpy(&arr[4], sdebug_inq_vendor_id, 8);
     memcpy(&arr[12], sdebug_inq_product_id, 16);
     memcpy(&arr[28], dev_id_str, dev_id_str_len);
     num = 8 + 16 + dev_id_str_len;
     arr[3] = num;
     num += 4;
     if (dev_id_num >= 0) {
         if (sdebug_uuid_ctl) {
             /* Locally assigned UUID */
             arr[num++] = 0x1;  /* binary (not necessarily sas) */
             arr[num++] = 0xa;  /* PIV=0, lu, naa */
             arr[num++] = 0x0;
             arr[num++] = 0x12;
             arr[num++] = 0x10; /* uuid type=1, locally assigned */
             arr[num++] = 0x0;
             memcpy(arr + num, lu_name, 16);
             num += 16;
         } else {
             /* NAA-3, Logical unit identifier (binary) */
             arr[num++] = 0x1;  /* binary (not necessarily sas) */
             arr[num++] = 0x3;  /* PIV=0, lu, naa */
             arr[num++] = 0x0;
             arr[num++] = 0x8;
             put_unaligned_be64(naa3_comp_b + dev_id_num, arr + num);
             num += 8;
         }
         /* Target relative port number */
         arr[num++] = 0x61;  /* proto=sas, binary */
         arr[num++] = 0x94;  /* PIV=1, target port, rel port */
         arr[num++] = 0x0;   /* reserved */
         arr[num++] = 0x4;   /* length */
         arr[num++] = 0x0;   /* reserved */
         arr[num++] = 0x0;   /* reserved */
         arr[num++] = 0x0;
         arr[num++] = 0x1;   /* relative port A */
     }
     /* NAA-3, Target port identifier */
     arr[num++] = 0x61;  /* proto=sas, binary */
     arr[num++] = 0x93;  /* piv=1, target port, naa */
     arr[num++] = 0x0;
     arr[num++] = 0x8;
     put_unaligned_be64(naa3_comp_a + port_a, arr + num);
     num += 8;
     /* NAA-3, Target port group identifier */
     arr[num++] = 0x61;  /* proto=sas, binary */
     arr[num++] = 0x95;  /* piv=1, target port group id */
     arr[num++] = 0x0;
     arr[num++] = 0x4;
     arr[num++] = 0;
     arr[num++] = 0;
     put_unaligned_be16(port_group_id, arr + num);
     num += 2;
     /* NAA-3, Target device identifier */
     arr[num++] = 0x61;  /* proto=sas, binary */
     arr[num++] = 0xa3;  /* piv=1, target device, naa */
     arr[num++] = 0x0;
     arr[num++] = 0x8;
     put_unaligned_be64(naa3_comp_a + target_dev_id, arr + num);
     num += 8;
     /* SCSI name string: Target device identifier */
     arr[num++] = 0x63;  /* proto=sas, UTF-8 */
     arr[num++] = 0xa8;  /* piv=1, target device, SCSI name string */
     arr[num++] = 0x0;
     arr[num++] = 24;
     memcpy(arr + num, "naa.32222220", 12);
     num += 12;
     snprintf(b, sizeof(b), "%08X", target_dev_id);
     memcpy(arr + num, b, 8);
     num += 8;
     memset(arr + num, 0, 4);
     num += 4;
     return num;
 }
 
 static unsigned char vpd84_data[] = {
 /* from 4th byte */ 0x22,0x22,0x22,0x0,0xbb,0x0,
     0x22,0x22,0x22,0x0,0xbb,0x1,
     0x22,0x22,0x22,0x0,0xbb,0x2,
 };
 
 /*  Software interface identification VPD page */
 static int inquiry_vpd_84(unsigned char *arr)
 {
     memcpy(arr, vpd84_data, sizeof(vpd84_data));
     return sizeof(vpd84_data);
 }
 
 /* Management network addresses VPD page */
 static int inquiry_vpd_85(unsigned char *arr)
 {
     int num = 0;
     const char *na1 = "https://www.kernel.org/config";
     const char *na2 = "http://www.kernel.org/log";
     int plen, olen;
 
     arr[num++] = 0x1;   /* lu, storage config */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;
     olen = strlen(na1);
     plen = olen + 1;
     if (plen % 4)
         plen = ((plen / 4) + 1) * 4;
     arr[num++] = plen;  /* length, null termianted, padded */
     memcpy(arr + num, na1, olen);
     memset(arr + num + olen, 0, plen - olen);
     num += plen;
 
     arr[num++] = 0x4;   /* lu, logging */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;
     olen = strlen(na2);
     plen = olen + 1;
     if (plen % 4)
         plen = ((plen / 4) + 1) * 4;
     arr[num++] = plen;  /* length, null terminated, padded */
     memcpy(arr + num, na2, olen);
     memset(arr + num + olen, 0, plen - olen);
     num += plen;
 
     return num;
 }
 
 /* SCSI ports VPD page */
 static int inquiry_vpd_88(unsigned char *arr, int target_dev_id)
 {
     int num = 0;
     int port_a, port_b;
 
     port_a = target_dev_id + 1;
     port_b = port_a + 1;
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;
     arr[num++] = 0x1;   /* relative port 1 (primary) */
     memset(arr + num, 0, 6);
     num += 6;
     arr[num++] = 0x0;
     arr[num++] = 12;    /* length tp descriptor */
     /* naa-5 target port identifier (A) */
     arr[num++] = 0x61;  /* proto=sas, binary */
     arr[num++] = 0x93;  /* PIV=1, target port, NAA */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x8;   /* length */
     put_unaligned_be64(naa3_comp_a + port_a, arr + num);
     num += 8;
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x0;
     arr[num++] = 0x2;   /* relative port 2 (secondary) */
     memset(arr + num, 0, 6);
     num += 6;
     arr[num++] = 0x0;
     arr[num++] = 12;    /* length tp descriptor */
     /* naa-5 target port identifier (B) */
     arr[num++] = 0x61;  /* proto=sas, binary */
     arr[num++] = 0x93;  /* PIV=1, target port, NAA */
     arr[num++] = 0x0;   /* reserved */
     arr[num++] = 0x8;   /* length */
     put_unaligned_be64(naa3_comp_a + port_b, arr + num);
     num += 8;
 
     return num;
 }
 
 
 static unsigned char vpd89_data[] = {
 /* from 4th byte */ 0,0,0,0,
 'l','i','n','u','x',' ',' ',' ',
 'S','A','T',' ','s','c','s','i','_','d','e','b','u','g',' ',' ',
 '1','2','3','4',
 0x34,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,
 0xec,0,0,0,
 0x5a,0xc,0xff,0x3f,0x37,0xc8,0x10,0,0,0,0,0,0x3f,0,0,0,
 0,0,0,0,0x58,0x58,0x58,0x58,0x58,0x58,0x58,0x58,0x20,0x20,0x20,0x20,
 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0,0,0,0x40,0x4,0,0x2e,0x33,
 0x38,0x31,0x20,0x20,0x20,0x20,0x54,0x53,0x38,0x33,0x30,0x30,0x33,0x31,
 0x53,0x41,
 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
 0x20,0x20,
 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
 0x10,0x80,
 0,0,0,0x2f,0,0,0,0x2,0,0x2,0x7,0,0xff,0xff,0x1,0,
 0x3f,0,0xc1,0xff,0x3e,0,0x10,0x1,0xb0,0xf8,0x50,0x9,0,0,0x7,0,
 0x3,0,0x78,0,0x78,0,0xf0,0,0x78,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0x2,0,0,0,0,0,0,0,
 0x7e,0,0x1b,0,0x6b,0x34,0x1,0x7d,0x3,0x40,0x69,0x34,0x1,0x3c,0x3,0x40,
 0x7f,0x40,0,0,0,0,0xfe,0xfe,0,0,0,0,0,0xfe,0,0,
 0,0,0,0,0,0,0,0,0xb0,0xf8,0x50,0x9,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0x1,0,0xb0,0xf8,0x50,0x9,0xb0,0xf8,0x50,0x9,0x20,0x20,0x2,0,0xb6,0x42,
 0,0x80,0x8a,0,0x6,0x3c,0xa,0x3c,0xff,0xff,0xc6,0x7,0,0x1,0,0x8,
 0xf0,0xf,0,0x10,0x2,0,0x30,0,0,0,0,0,0,0,0x6,0xfe,
 0,0,0x2,0,0x50,0,0x8a,0,0x4f,0x95,0,0,0x21,0,0xb,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0xa5,0x51,
 };
 
 /* ATA Information VPD page */
 static int inquiry_vpd_89(unsigned char *arr)
 {
     memcpy(arr, vpd89_data, sizeof(vpd89_data));
     return sizeof(vpd89_data);
 }
 
 
 static unsigned char vpdb0_data[] = {
     /* from 4th byte */ 0,0,0,4, 0,0,0x4,0, 0,0,0,64,
     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
 };
 
 /* Block limits VPD page (SBC-3) */
 static int inquiry_vpd_b0(unsigned char *arr)
 {
     unsigned int gran;
 
     memcpy(arr, vpdb0_data, sizeof(vpdb0_data));
 
     /* Optimal transfer length granularity */
     if (sdebug_opt_xferlen_exp != 0 &&
         sdebug_physblk_exp < sdebug_opt_xferlen_exp)
         gran = 1 << sdebug_opt_xferlen_exp;
     else
         gran = 1 << sdebug_physblk_exp;
     put_unaligned_be16(gran, arr + 2);
 
     /* Maximum Transfer Length */
     if (sdebug_store_sectors > 0x400)
         put_unaligned_be32(sdebug_store_sectors, arr + 4);
 
     /* Optimal Transfer Length */
     put_unaligned_be32(sdebug_opt_blks, &arr[8]);
 
     if (sdebug_lbpu) {
         /* Maximum Unmap LBA Count */
         put_unaligned_be32(sdebug_unmap_max_blocks, &arr[16]);
 
         /* Maximum Unmap Block Descriptor Count */
         put_unaligned_be32(sdebug_unmap_max_desc, &arr[20]);
     }
 
     /* Unmap Granularity Alignment */
     if (sdebug_unmap_alignment) {
         put_unaligned_be32(sdebug_unmap_alignment, &arr[28]);
         arr[28] |= 0x80; /* UGAVALID */
     }
 
     /* Optimal Unmap Granularity */
     put_unaligned_be32(sdebug_unmap_granularity, &arr[24]);
 
     /* Maximum WRITE SAME Length */
     put_unaligned_be64(sdebug_write_same_length, &arr[32]);
 
     return 0x3c; /* Mandatory page length for Logical Block Provisioning */
 
     return sizeof(vpdb0_data);
 }
 
 /* Block device characteristics VPD page (SBC-3) */
 static int inquiry_vpd_b1(struct sdebug_dev_info *devip, unsigned char *arr)
 {
     memset(arr, 0, 0x3c);
     arr[0] = 0;
     arr[1] = 1; /* non rotating medium (e.g. solid state) */
     arr[2] = 0;
     arr[3] = 5; /* less than 1.8" */
     if (devip->zmodel == BLK_ZONED_HA)
         arr[4] = 1 << 4;    /* zoned field = 01b */
 
     return 0x3c;
 }
 
 /* Logical block provisioning VPD page (SBC-4) */
 static int inquiry_vpd_b2(unsigned char *arr)
 {
     memset(arr, 0, 0x4);
     arr[0] = 0;         /* threshold exponent */
     if (sdebug_lbpu)
         arr[1] = 1 << 7;
     if (sdebug_lbpws)
         arr[1] |= 1 << 6;
     if (sdebug_lbpws10)
         arr[1] |= 1 << 5;
     if (sdebug_lbprz && scsi_debug_lbp())
         arr[1] |= (sdebug_lbprz & 0x7) << 2;  /* sbc4r07 and later */
     /* anc_sup=0; dp=0 (no provisioning group descriptor) */
     /* minimum_percentage=0; provisioning_type=0 (unknown) */
     /* threshold_percentage=0 */
     return 0x4;
 }
 
 /* Zoned block device characteristics VPD page (ZBC mandatory) */
 static int inquiry_vpd_b6(struct sdebug_dev_info *devip, unsigned char *arr)
 {
     memset(arr, 0, 0x3c);
     arr[0] = 0x1; /* set URSWRZ (unrestricted read in seq. wr req zone) */
     /*
      * Set Optimal number of open sequential write preferred zones and
      * Optimal number of non-sequentially written sequential write
      * preferred zones fields to 'not reported' (0xffffffff). Leave other
      * fields set to zero, apart from Max. number of open swrz_s field.
      */
     put_unaligned_be32(0xffffffff, &arr[4]);
     put_unaligned_be32(0xffffffff, &arr[8]);
     if (sdeb_zbc_model == BLK_ZONED_HM && devip->max_open)
         put_unaligned_be32(devip->max_open, &arr[12]);
     else
         put_unaligned_be32(0xffffffff, &arr[12]);
     if (devip->zcap < devip->zsize) {
         arr[19] = ZBC_CONSTANT_ZONE_START_OFFSET;
         put_unaligned_be64(devip->zsize, &arr[20]);
     } else {
         arr[19] = 0;
     }
     return 0x3c;
 }
 
 #define SDEBUG_LONG_INQ_SZ 96
 #define SDEBUG_MAX_INQ_ARR_SZ 584
 
 static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     unsigned char pq_pdt;
     unsigned char *arr;
     unsigned char *cmd = scp->cmnd;
     u32 alloc_len, n;
     int ret;
     bool have_wlun, is_disk, is_zbc, is_disk_zbc;
 
     alloc_len = get_unaligned_be16(cmd + 3);
     arr = kzalloc(SDEBUG_MAX_INQ_ARR_SZ, GFP_ATOMIC);
     if (! arr)
         return DID_REQUEUE << 16;
     is_disk = (sdebug_ptype == TYPE_DISK);
     is_zbc = (devip->zmodel != BLK_ZONED_NONE);
     is_disk_zbc = (is_disk || is_zbc);
     have_wlun = scsi_is_wlun(scp->device->lun);
     if (have_wlun)
         pq_pdt = TYPE_WLUN; /* present, wlun */
     else if (sdebug_no_lun_0 && (devip->lun == SDEBUG_LUN_0_VAL))
         pq_pdt = 0x7f;  /* not present, PQ=3, PDT=0x1f */
     else
         pq_pdt = (sdebug_ptype & 0x1f);
     arr[0] = pq_pdt;
     if (0x2 & cmd[1]) {  /* CMDDT bit set */
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 1);
         kfree(arr);
         return check_condition_result;
     } else if (0x1 & cmd[1]) {  /* EVPD bit set */
         int lu_id_num, port_group_id, target_dev_id;
         u32 len;
         char lu_id_str[6];
         int host_no = devip->sdbg_host->shost->host_no;
         
         port_group_id = (((host_no + 1) & 0x7f) << 8) +
             (devip->channel & 0x7f);
         if (sdebug_vpd_use_hostno == 0)
             host_no = 0;
         lu_id_num = have_wlun ? -1 : (((host_no + 1) * 2000) +
                 (devip->target * 1000) + devip->lun);
         target_dev_id = ((host_no + 1) * 2000) +
                  (devip->target * 1000) - 3;
         len = scnprintf(lu_id_str, 6, "%d", lu_id_num);
         if (0 == cmd[2]) { /* supported vital product data pages */
             arr[1] = cmd[2];    /*sanity */
             n = 4;
             arr[n++] = 0x0;   /* this page */
             arr[n++] = 0x80;  /* unit serial number */
             arr[n++] = 0x83;  /* device identification */
             arr[n++] = 0x84;  /* software interface ident. */
             arr[n++] = 0x85;  /* management network addresses */
             arr[n++] = 0x86;  /* extended inquiry */
             arr[n++] = 0x87;  /* mode page policy */
             arr[n++] = 0x88;  /* SCSI ports */
             if (is_disk_zbc) {    /* SBC or ZBC */
                 arr[n++] = 0x89;  /* ATA information */
                 arr[n++] = 0xb0;  /* Block limits */
                 arr[n++] = 0xb1;  /* Block characteristics */
                 if (is_disk)
                     arr[n++] = 0xb2;  /* LB Provisioning */
                 if (is_zbc)
                     arr[n++] = 0xb6;  /* ZB dev. char. */
             }
             arr[3] = n - 4;   /* number of supported VPD pages */
         } else if (0x80 == cmd[2]) { /* unit serial number */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = len;
             memcpy(&arr[4], lu_id_str, len);
         } else if (0x83 == cmd[2]) { /* device identification */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = inquiry_vpd_83(&arr[4], port_group_id,
                         target_dev_id, lu_id_num,
                         lu_id_str, len,
                         &devip->lu_name);
         } else if (0x84 == cmd[2]) { /* Software interface ident. */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = inquiry_vpd_84(&arr[4]);
         } else if (0x85 == cmd[2]) { /* Management network addresses */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = inquiry_vpd_85(&arr[4]);
         } else if (0x86 == cmd[2]) { /* extended inquiry */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = 0x3c;  /* number of following entries */
             if (sdebug_dif == T10_PI_TYPE3_PROTECTION)
                 arr[4] = 0x4;   /* SPT: GRD_CHK:1 */
             else if (have_dif_prot)
                 arr[4] = 0x5;   /* SPT: GRD_CHK:1, REF_CHK:1 */
             else
                 arr[4] = 0x0;   /* no protection stuff */
             arr[5] = 0x7;   /* head of q, ordered + simple q's */
         } else if (0x87 == cmd[2]) { /* mode page policy */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = 0x8;   /* number of following entries */
             arr[4] = 0x2;   /* disconnect-reconnect mp */
             arr[6] = 0x80;  /* mlus, shared */
             arr[8] = 0x18;   /* protocol specific lu */
             arr[10] = 0x82;  /* mlus, per initiator port */
         } else if (0x88 == cmd[2]) { /* SCSI Ports */
             arr[1] = cmd[2];    /*sanity */
             arr[3] = inquiry_vpd_88(&arr[4], target_dev_id);
         } else if (is_disk_zbc && 0x89 == cmd[2]) { /* ATA info */
             arr[1] = cmd[2];        /*sanity */
             n = inquiry_vpd_89(&arr[4]);
             put_unaligned_be16(n, arr + 2);
         } else if (is_disk_zbc && 0xb0 == cmd[2]) { /* Block limits */
             arr[1] = cmd[2];        /*sanity */
             arr[3] = inquiry_vpd_b0(&arr[4]);
         } else if (is_disk_zbc && 0xb1 == cmd[2]) { /* Block char. */
             arr[1] = cmd[2];        /*sanity */
             arr[3] = inquiry_vpd_b1(devip, &arr[4]);
         } else if (is_disk && 0xb2 == cmd[2]) { /* LB Prov. */
             arr[1] = cmd[2];        /*sanity */
             arr[3] = inquiry_vpd_b2(&arr[4]);
         } else if (is_zbc && cmd[2] == 0xb6) { /* ZB dev. charact. */
             arr[1] = cmd[2];        /*sanity */
             arr[3] = inquiry_vpd_b6(devip, &arr[4]);
         } else {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, -1);
             kfree(arr);
             return check_condition_result;
         }
         len = min_t(u32, get_unaligned_be16(arr + 2) + 4, alloc_len);
         ret = fill_from_dev_buffer(scp, arr,
                 min_t(u32, len, SDEBUG_MAX_INQ_ARR_SZ));
         kfree(arr);
         return ret;
     }
     /* drops through here for a standard inquiry */
     arr[1] = sdebug_removable ? 0x80 : 0;   /* Removable disk */
     arr[2] = sdebug_scsi_level;
     arr[3] = 2;    /* response_data_format==2 */
     arr[4] = SDEBUG_LONG_INQ_SZ - 5;
     arr[5] = (int)have_dif_prot;    /* PROTECT bit */
     if (sdebug_vpd_use_hostno == 0)
         arr[5] |= 0x10; /* claim: implicit TPGS */
     arr[6] = 0x10; /* claim: MultiP */
     /* arr[6] |= 0x40; ... claim: EncServ (enclosure services) */
     arr[7] = 0xa; /* claim: LINKED + CMDQUE */
     memcpy(&arr[8], sdebug_inq_vendor_id, 8);
     memcpy(&arr[16], sdebug_inq_product_id, 16);
     memcpy(&arr[32], sdebug_inq_product_rev, 4);
     /* Use Vendor Specific area to place driver date in ASCII hex */
     memcpy(&arr[36], sdebug_version_date, 8);
     /* version descriptors (2 bytes each) follow */
     put_unaligned_be16(0xc0, arr + 58);   /* SAM-6 no version claimed */
     put_unaligned_be16(0x5c0, arr + 60);  /* SPC-5 no version claimed */
     n = 62;
     if (is_disk) {      /* SBC-4 no version claimed */
         put_unaligned_be16(0x600, arr + n);
         n += 2;
     } else if (sdebug_ptype == TYPE_TAPE) { /* SSC-4 rev 3 */
         put_unaligned_be16(0x525, arr + n);
         n += 2;
     } else if (is_zbc) {    /* ZBC BSR INCITS 536 revision 05 */
         put_unaligned_be16(0x624, arr + n);
         n += 2;
     }
     put_unaligned_be16(0x2100, arr + n);    /* SPL-4 no version claimed */
     ret = fill_from_dev_buffer(scp, arr,
                 min_t(u32, alloc_len, SDEBUG_LONG_INQ_SZ));
     kfree(arr);
     return ret;
 }
 
 /* See resp_iec_m_pg() for how this data is manipulated */
 static unsigned char iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
                    0, 0, 0x0, 0x0};
 
 static int resp_requests(struct scsi_cmnd *scp,
              struct sdebug_dev_info *devip)
 {
     unsigned char *cmd = scp->cmnd;
     unsigned char arr[SCSI_SENSE_BUFFERSIZE];   /* assume >= 18 bytes */
     bool dsense = !!(cmd[1] & 1);
     u32 alloc_len = cmd[4];
     u32 len = 18;
     int stopped_state = atomic_read(&devip->stopped);
 
     memset(arr, 0, sizeof(arr));
     if (stopped_state > 0) {    /* some "pollable" data [spc6r02: 5.12.2] */
         if (dsense) {
             arr[0] = 0x72;
             arr[1] = NOT_READY;
             arr[2] = LOGICAL_UNIT_NOT_READY;
             arr[3] = (stopped_state == 2) ? 0x1 : 0x2;
             len = 8;
         } else {
             arr[0] = 0x70;
             arr[2] = NOT_READY;     /* NO_SENSE in sense_key */
             arr[7] = 0xa;           /* 18 byte sense buffer */
             arr[12] = LOGICAL_UNIT_NOT_READY;
             arr[13] = (stopped_state == 2) ? 0x1 : 0x2;
         }
     } else if ((iec_m_pg[2] & 0x4) && (6 == (iec_m_pg[3] & 0xf))) {
         /* Information exceptions control mode page: TEST=1, MRIE=6 */
         if (dsense) {
             arr[0] = 0x72;
             arr[1] = 0x0;       /* NO_SENSE in sense_key */
             arr[2] = THRESHOLD_EXCEEDED;
             arr[3] = 0xff;      /* Failure prediction(false) */
             len = 8;
         } else {
             arr[0] = 0x70;
             arr[2] = 0x0;       /* NO_SENSE in sense_key */
             arr[7] = 0xa;       /* 18 byte sense buffer */
             arr[12] = THRESHOLD_EXCEEDED;
             arr[13] = 0xff;     /* Failure prediction(false) */
         }
     } else {    /* nothing to report */
         if (dsense) {
             len = 8;
             memset(arr, 0, len);
             arr[0] = 0x72;
         } else {
             memset(arr, 0, len);
             arr[0] = 0x70;
             arr[7] = 0xa;
         }
     }
     return fill_from_dev_buffer(scp, arr, min_t(u32, len, alloc_len));
 }
 
 static int resp_start_stop(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     unsigned char *cmd = scp->cmnd;
     int power_cond, want_stop, stopped_state;
     bool changing;
 
     power_cond = (cmd[4] & 0xf0) >> 4;
     if (power_cond) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, 7);
         return check_condition_result;
     }
     want_stop = !(cmd[4] & 1);
     stopped_state = atomic_read(&devip->stopped);
     if (stopped_state == 2) {
         ktime_t now_ts = ktime_get_boottime();
 
         if (ktime_to_ns(now_ts) > ktime_to_ns(devip->create_ts)) {
             u64 diff_ns = ktime_to_ns(ktime_sub(now_ts, devip->create_ts));
 
             if (diff_ns >= ((u64)sdeb_tur_ms_to_ready * 1000000)) {
                 /* tur_ms_to_ready timer extinguished */
                 atomic_set(&devip->stopped, 0);
                 stopped_state = 0;
             }
         }
         if (stopped_state == 2) {
             if (want_stop) {
                 stopped_state = 1;  /* dummy up success */
             } else {    /* Disallow tur_ms_to_ready delay to be overridden */
                 mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, 0 /* START bit */);
                 return check_condition_result;
             }
         }
     }
     changing = (stopped_state != want_stop);
     if (changing)
         atomic_xchg(&devip->stopped, want_stop);
     if (!changing || (cmd[1] & 0x1))  /* state unchanged or IMMED bit set in cdb */
         return SDEG_RES_IMMED_MASK;
     else
         return 0;
 }
 
 static sector_t get_sdebug_capacity(void)
 {
     static const unsigned int gibibyte = 1073741824;
 
     if (sdebug_virtual_gb > 0)
         return (sector_t)sdebug_virtual_gb *
             (gibibyte / sdebug_sector_size);
     else
         return sdebug_store_sectors;
 }
 
 #define SDEBUG_READCAP_ARR_SZ 8
 static int resp_readcap(struct scsi_cmnd *scp,
             struct sdebug_dev_info *devip)
 {
     unsigned char arr[SDEBUG_READCAP_ARR_SZ];
     unsigned int capac;
 
     /* following just in case virtual_gb changed */
     sdebug_capacity = get_sdebug_capacity();
     memset(arr, 0, SDEBUG_READCAP_ARR_SZ);
     if (sdebug_capacity < 0xffffffff) {
         capac = (unsigned int)sdebug_capacity - 1;
         put_unaligned_be32(capac, arr + 0);
     } else
         put_unaligned_be32(0xffffffff, arr + 0);
     put_unaligned_be16(sdebug_sector_size, arr + 6);
     return fill_from_dev_buffer(scp, arr, SDEBUG_READCAP_ARR_SZ);
 }
 
 #define SDEBUG_READCAP16_ARR_SZ 32
 static int resp_readcap16(struct scsi_cmnd *scp,
               struct sdebug_dev_info *devip)
 {
     unsigned char *cmd = scp->cmnd;
     unsigned char arr[SDEBUG_READCAP16_ARR_SZ];
     u32 alloc_len;
 
     alloc_len = get_unaligned_be32(cmd + 10);
     /* following just in case virtual_gb changed */
     sdebug_capacity = get_sdebug_capacity();
     memset(arr, 0, SDEBUG_READCAP16_ARR_SZ);
     put_unaligned_be64((u64)(sdebug_capacity - 1), arr + 0);
     put_unaligned_be32(sdebug_sector_size, arr + 8);
     arr[13] = sdebug_physblk_exp & 0xf;
     arr[14] = (sdebug_lowest_aligned >> 8) & 0x3f;
 
     if (scsi_debug_lbp()) {
         arr[14] |= 0x80; /* LBPME */
         /* from sbc4r07, this LBPRZ field is 1 bit, but the LBPRZ in
          * the LB Provisioning VPD page is 3 bits. Note that lbprz=2
          * in the wider field maps to 0 in this field.
          */
         if (sdebug_lbprz & 1)   /* precisely what the draft requires */
             arr[14] |= 0x40;
     }
 
     arr[15] = sdebug_lowest_aligned & 0xff;
 
     if (have_dif_prot) {
         arr[12] = (sdebug_dif - 1) << 1; /* P_TYPE */
         arr[12] |= 1; /* PROT_EN */
     }
 
     return fill_from_dev_buffer(scp, arr,
                 min_t(u32, alloc_len, SDEBUG_READCAP16_ARR_SZ));
 }
 
 #define SDEBUG_MAX_TGTPGS_ARR_SZ 1412
 
 static int resp_report_tgtpgs(struct scsi_cmnd *scp,
                   struct sdebug_dev_info *devip)
 {
     unsigned char *cmd = scp->cmnd;
     unsigned char *arr;
     int host_no = devip->sdbg_host->shost->host_no;
     int port_group_a, port_group_b, port_a, port_b;
     u32 alen, n, rlen;
     int ret;
 
     alen = get_unaligned_be32(cmd + 6);
     arr = kzalloc(SDEBUG_MAX_TGTPGS_ARR_SZ, GFP_ATOMIC);
     if (! arr)
         return DID_REQUEUE << 16;
     /*
      * EVPD page 0x88 states we have two ports, one
      * real and a fake port with no device connected.
      * So we create two port groups with one port each
      * and set the group with port B to unavailable.
      */
     port_a = 0x1; /* relative port A */
     port_b = 0x2; /* relative port B */
     port_group_a = (((host_no + 1) & 0x7f) << 8) +
             (devip->channel & 0x7f);
     port_group_b = (((host_no + 1) & 0x7f) << 8) +
             (devip->channel & 0x7f) + 0x80;
 
     /*
      * The asymmetric access state is cycled according to the host_id.
      */
     n = 4;
     if (sdebug_vpd_use_hostno == 0) {
         arr[n++] = host_no % 3; /* Asymm access state */
         arr[n++] = 0x0F; /* claim: all states are supported */
     } else {
         arr[n++] = 0x0; /* Active/Optimized path */
         arr[n++] = 0x01; /* only support active/optimized paths */
     }
     put_unaligned_be16(port_group_a, arr + n);
     n += 2;
     arr[n++] = 0;    /* Reserved */
     arr[n++] = 0;    /* Status code */
     arr[n++] = 0;    /* Vendor unique */
     arr[n++] = 0x1;  /* One port per group */
     arr[n++] = 0;    /* Reserved */
     arr[n++] = 0;    /* Reserved */
     put_unaligned_be16(port_a, arr + n);
     n += 2;
     arr[n++] = 3;    /* Port unavailable */
     arr[n++] = 0x08; /* claim: only unavailalbe paths are supported */
     put_unaligned_be16(port_group_b, arr + n);
     n += 2;
     arr[n++] = 0;    /* Reserved */
     arr[n++] = 0;    /* Status code */
     arr[n++] = 0;    /* Vendor unique */
     arr[n++] = 0x1;  /* One port per group */
     arr[n++] = 0;    /* Reserved */
     arr[n++] = 0;    /* Reserved */
     put_unaligned_be16(port_b, arr + n);
     n += 2;
 
     rlen = n - 4;
     put_unaligned_be32(rlen, arr + 0);
 
     /*
      * Return the smallest value of either
      * - The allocated length
      * - The constructed command length
      * - The maximum array size
      */
     rlen = min(alen, n);
     ret = fill_from_dev_buffer(scp, arr,
                min_t(u32, rlen, SDEBUG_MAX_TGTPGS_ARR_SZ));
     kfree(arr);
     return ret;
 }
 
 static int resp_rsup_opcodes(struct scsi_cmnd *scp,
                  struct sdebug_dev_info *devip)
 {
     bool rctd;
     u8 reporting_opts, req_opcode, sdeb_i, supp;
     u16 req_sa, u;
     u32 alloc_len, a_len;
     int k, offset, len, errsts, count, bump, na;
     const struct opcode_info_t *oip;
     const struct opcode_info_t *r_oip;
     u8 *arr;
     u8 *cmd = scp->cmnd;
 
     rctd = !!(cmd[2] & 0x80);
     reporting_opts = cmd[2] & 0x7;
     req_opcode = cmd[3];
     req_sa = get_unaligned_be16(cmd + 4);
     alloc_len = get_unaligned_be32(cmd + 6);
     if (alloc_len < 4 || alloc_len > 0xffff) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
         return check_condition_result;
     }
     if (alloc_len > 8192)
         a_len = 8192;
     else
         a_len = alloc_len;
     arr = kzalloc((a_len < 256) ? 320 : a_len + 64, GFP_ATOMIC);
     if (NULL == arr) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
                 INSUFF_RES_ASCQ);
         return check_condition_result;
     }
     switch (reporting_opts) {
     case 0: /* all commands */
         /* count number of commands */
         for (count = 0, oip = opcode_info_arr;
              oip->num_attached != 0xff; ++oip) {
             if (F_INV_OP & oip->flags)
                 continue;
             count += (oip->num_attached + 1);
         }
         bump = rctd ? 20 : 8;
         put_unaligned_be32(count * bump, arr);
         for (offset = 4, oip = opcode_info_arr;
              oip->num_attached != 0xff && offset < a_len; ++oip) {
             if (F_INV_OP & oip->flags)
                 continue;
             na = oip->num_attached;
             arr[offset] = oip->opcode;
             put_unaligned_be16(oip->sa, arr + offset + 2);
             if (rctd)
                 arr[offset + 5] |= 0x2;
             if (FF_SA & oip->flags)
                 arr[offset + 5] |= 0x1;
             put_unaligned_be16(oip->len_mask[0], arr + offset + 6);
             if (rctd)
                 put_unaligned_be16(0xa, arr + offset + 8);
             r_oip = oip;
             for (k = 0, oip = oip->arrp; k < na; ++k, ++oip) {
                 if (F_INV_OP & oip->flags)
                     continue;
                 offset += bump;
                 arr[offset] = oip->opcode;
                 put_unaligned_be16(oip->sa, arr + offset + 2);
                 if (rctd)
                     arr[offset + 5] |= 0x2;
                 if (FF_SA & oip->flags)
                     arr[offset + 5] |= 0x1;
                 put_unaligned_be16(oip->len_mask[0],
                            arr + offset + 6);
                 if (rctd)
                     put_unaligned_be16(0xa,
                                arr + offset + 8);
             }
             oip = r_oip;
             offset += bump;
         }
         break;
     case 1: /* one command: opcode only */
     case 2: /* one command: opcode plus service action */
     case 3: /* one command: if sa==0 then opcode only else opcode+sa */
         sdeb_i = opcode_ind_arr[req_opcode];
         oip = &opcode_info_arr[sdeb_i];
         if (F_INV_OP & oip->flags) {
             supp = 1;
             offset = 4;
         } else {
             if (1 == reporting_opts) {
                 if (FF_SA & oip->flags) {
                     mk_sense_invalid_fld(scp, SDEB_IN_CDB,
                                  2, 2);
                     kfree(arr);
                     return check_condition_result;
                 }
                 req_sa = 0;
             } else if (2 == reporting_opts &&
                    0 == (FF_SA & oip->flags)) {
                 mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, -1);
                 kfree(arr); /* point at requested sa */
                 return check_condition_result;
             }
             if (0 == (FF_SA & oip->flags) &&
                 req_opcode == oip->opcode)
                 supp = 3;
             else if (0 == (FF_SA & oip->flags)) {
                 na = oip->num_attached;
                 for (k = 0, oip = oip->arrp; k < na;
                      ++k, ++oip) {
                     if (req_opcode == oip->opcode)
                         break;
                 }
                 supp = (k >= na) ? 1 : 3;
             } else if (req_sa != oip->sa) {
                 na = oip->num_attached;
                 for (k = 0, oip = oip->arrp; k < na;
                      ++k, ++oip) {
                     if (req_sa == oip->sa)
                         break;
                 }
                 supp = (k >= na) ? 1 : 3;
             } else
                 supp = 3;
             if (3 == supp) {
                 u = oip->len_mask[0];
                 put_unaligned_be16(u, arr + 2);
                 arr[4] = oip->opcode;
                 for (k = 1; k < u; ++k)
                     arr[4 + k] = (k < 16) ?
                          oip->len_mask[k] : 0xff;
                 offset = 4 + u;
             } else
                 offset = 4;
         }
         arr[1] = (rctd ? 0x80 : 0) | supp;
         if (rctd) {
             put_unaligned_be16(0xa, arr + offset);
             offset += 12;
         }
         break;
     default:
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 2);
         kfree(arr);
         return check_condition_result;
     }
     offset = (offset < a_len) ? offset : a_len;
     len = (offset < alloc_len) ? offset : alloc_len;
     errsts = fill_from_dev_buffer(scp, arr, len);
     kfree(arr);
     return errsts;
 }
 
 static int resp_rsup_tmfs(struct scsi_cmnd *scp,
               struct sdebug_dev_info *devip)
 {
     bool repd;
     u32 alloc_len, len;
     u8 arr[16];
     u8 *cmd = scp->cmnd;
 
     memset(arr, 0, sizeof(arr));
     repd = !!(cmd[2] & 0x80);
     alloc_len = get_unaligned_be32(cmd + 6);
     if (alloc_len < 4) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
         return check_condition_result;
     }
     arr[0] = 0xc8;      /* ATS | ATSS | LURS */
     arr[1] = 0x1;       /* ITNRS */
     if (repd) {
         arr[3] = 0xc;
         len = 16;
     } else
         len = 4;
 
     len = (len < alloc_len) ? len : alloc_len;
     return fill_from_dev_buffer(scp, arr, len);
 }
 
 /* <<Following mode page info copied from ST318451LW>> */
 
 static int resp_err_recov_pg(unsigned char *p, int pcontrol, int target)
 {   /* Read-Write Error Recovery page for mode_sense */
     unsigned char err_recov_pg[] = {0x1, 0xa, 0xc0, 11, 240, 0, 0, 0,
                     5, 0, 0xff, 0xff};
 
     memcpy(p, err_recov_pg, sizeof(err_recov_pg));
     if (1 == pcontrol)
         memset(p + 2, 0, sizeof(err_recov_pg) - 2);
     return sizeof(err_recov_pg);
 }
 
 static int resp_disconnect_pg(unsigned char *p, int pcontrol, int target)
 {   /* Disconnect-Reconnect page for mode_sense */
     unsigned char disconnect_pg[] = {0x2, 0xe, 128, 128, 0, 10, 0, 0,
                      0, 0, 0, 0, 0, 0, 0, 0};
 
     memcpy(p, disconnect_pg, sizeof(disconnect_pg));
     if (1 == pcontrol)
         memset(p + 2, 0, sizeof(disconnect_pg) - 2);
     return sizeof(disconnect_pg);
 }
 
 static int resp_format_pg(unsigned char *p, int pcontrol, int target)
 {       /* Format device page for mode_sense */
     unsigned char format_pg[] = {0x3, 0x16, 0, 0, 0, 0, 0, 0,
                      0, 0, 0, 0, 0, 0, 0, 0,
                      0, 0, 0, 0, 0x40, 0, 0, 0};
 
     memcpy(p, format_pg, sizeof(format_pg));
     put_unaligned_be16(sdebug_sectors_per, p + 10);
     put_unaligned_be16(sdebug_sector_size, p + 12);
     if (sdebug_removable)
         p[20] |= 0x20; /* should agree with INQUIRY */
     if (1 == pcontrol)
         memset(p + 2, 0, sizeof(format_pg) - 2);
     return sizeof(format_pg);
 }
 
 static unsigned char caching_pg[] = {0x8, 18, 0x14, 0, 0xff, 0xff, 0, 0,
                      0xff, 0xff, 0xff, 0xff, 0x80, 0x14, 0, 0,
                      0, 0, 0, 0};
 
 static int resp_caching_pg(unsigned char *p, int pcontrol, int target)
 {   /* Caching page for mode_sense */
     unsigned char ch_caching_pg[] = {/* 0x8, 18, */ 0x4, 0, 0, 0, 0, 0,
         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
     unsigned char d_caching_pg[] = {0x8, 18, 0x14, 0, 0xff, 0xff, 0, 0,
         0xff, 0xff, 0xff, 0xff, 0x80, 0x14, 0, 0,     0, 0, 0, 0};
 
     if (SDEBUG_OPT_N_WCE & sdebug_opts)
         caching_pg[2] &= ~0x4;  /* set WCE=0 (default WCE=1) */
     memcpy(p, caching_pg, sizeof(caching_pg));
     if (1 == pcontrol)
         memcpy(p + 2, ch_caching_pg, sizeof(ch_caching_pg));
     else if (2 == pcontrol)
         memcpy(p, d_caching_pg, sizeof(d_caching_pg));
     return sizeof(caching_pg);
 }
 
 static unsigned char ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
                     0, 0, 0x2, 0x4b};
 
 static int resp_ctrl_m_pg(unsigned char *p, int pcontrol, int target)
 {   /* Control mode page for mode_sense */
     unsigned char ch_ctrl_m_pg[] = {/* 0xa, 10, */ 0x6, 0, 0, 0, 0, 0,
                     0, 0, 0, 0};
     unsigned char d_ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
                      0, 0, 0x2, 0x4b};
 
     if (sdebug_dsense)
         ctrl_m_pg[2] |= 0x4;
     else
         ctrl_m_pg[2] &= ~0x4;
 
     if (sdebug_ato)
         ctrl_m_pg[5] |= 0x80; /* ATO=1 */
 
     memcpy(p, ctrl_m_pg, sizeof(ctrl_m_pg));
     if (1 == pcontrol)
         memcpy(p + 2, ch_ctrl_m_pg, sizeof(ch_ctrl_m_pg));
     else if (2 == pcontrol)
         memcpy(p, d_ctrl_m_pg, sizeof(d_ctrl_m_pg));
     return sizeof(ctrl_m_pg);
 }
 
 
 static int resp_iec_m_pg(unsigned char *p, int pcontrol, int target)
 {   /* Informational Exceptions control mode page for mode_sense */
     unsigned char ch_iec_m_pg[] = {/* 0x1c, 0xa, */ 0x4, 0xf, 0, 0, 0, 0,
                        0, 0, 0x0, 0x0};
     unsigned char d_iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
                       0, 0, 0x0, 0x0};
 
     memcpy(p, iec_m_pg, sizeof(iec_m_pg));
     if (1 == pcontrol)
         memcpy(p + 2, ch_iec_m_pg, sizeof(ch_iec_m_pg));
     else if (2 == pcontrol)
         memcpy(p, d_iec_m_pg, sizeof(d_iec_m_pg));
     return sizeof(iec_m_pg);
 }
 
 static int resp_sas_sf_m_pg(unsigned char *p, int pcontrol, int target)
 {   /* SAS SSP mode page - short format for mode_sense */
     unsigned char sas_sf_m_pg[] = {0x19, 0x6,
         0x6, 0x0, 0x7, 0xd0, 0x0, 0x0};
 
     memcpy(p, sas_sf_m_pg, sizeof(sas_sf_m_pg));
     if (1 == pcontrol)
         memset(p + 2, 0, sizeof(sas_sf_m_pg) - 2);
     return sizeof(sas_sf_m_pg);
 }
 
 
 static int resp_sas_pcd_m_spg(unsigned char *p, int pcontrol, int target,
                   int target_dev_id)
 {   /* SAS phy control and discover mode page for mode_sense */
     unsigned char sas_pcd_m_pg[] = {0x59, 0x1, 0, 0x64, 0, 0x6, 0, 2,
             0, 0, 0, 0, 0x10, 0x9, 0x8, 0x0,
             0, 0, 0, 0, 0, 0, 0, 0, /* insert SAS addr */
             0, 0, 0, 0, 0, 0, 0, 0, /* insert SAS addr */
             0x2, 0, 0, 0, 0, 0, 0, 0,
             0x88, 0x99, 0, 0, 0, 0, 0, 0,
             0, 0, 0, 0, 0, 0, 0, 0,
             0, 1, 0, 0, 0x10, 0x9, 0x8, 0x0,
             0, 0, 0, 0, 0, 0, 0, 0, /* insert SAS addr */
             0, 0, 0, 0, 0, 0, 0, 0, /* insert SAS addr */
             0x3, 0, 0, 0, 0, 0, 0, 0,
             0x88, 0x99, 0, 0, 0, 0, 0, 0,
             0, 0, 0, 0, 0, 0, 0, 0,
         };
     int port_a, port_b;
 
     put_unaligned_be64(naa3_comp_a, sas_pcd_m_pg + 16);
     put_unaligned_be64(naa3_comp_c + 1, sas_pcd_m_pg + 24);
     put_unaligned_be64(naa3_comp_a, sas_pcd_m_pg + 64);
     put_unaligned_be64(naa3_comp_c + 1, sas_pcd_m_pg + 72);
     port_a = target_dev_id + 1;
     port_b = port_a + 1;
     memcpy(p, sas_pcd_m_pg, sizeof(sas_pcd_m_pg));
     put_unaligned_be32(port_a, p + 20);
     put_unaligned_be32(port_b, p + 48 + 20);
     if (1 == pcontrol)
         memset(p + 4, 0, sizeof(sas_pcd_m_pg) - 4);
     return sizeof(sas_pcd_m_pg);
 }
 
 static int resp_sas_sha_m_spg(unsigned char *p, int pcontrol)
 {   /* SAS SSP shared protocol specific port mode subpage */
     unsigned char sas_sha_m_pg[] = {0x59, 0x2, 0, 0xc, 0, 0x6, 0x10, 0,
             0, 0, 0, 0, 0, 0, 0, 0,
         };
 
     memcpy(p, sas_sha_m_pg, sizeof(sas_sha_m_pg));
     if (1 == pcontrol)
         memset(p + 4, 0, sizeof(sas_sha_m_pg) - 4);
     return sizeof(sas_sha_m_pg);
 }
 
 #define SDEBUG_MAX_MSENSE_SZ 256
 
 static int resp_mode_sense(struct scsi_cmnd *scp,
                struct sdebug_dev_info *devip)
 {
     int pcontrol, pcode, subpcode, bd_len;
     unsigned char dev_spec;
     u32 alloc_len, offset, len;
     int target_dev_id;
     int target = scp->device->id;
     unsigned char *ap;
     unsigned char arr[SDEBUG_MAX_MSENSE_SZ];
     unsigned char *cmd = scp->cmnd;
     bool dbd, llbaa, msense_6, is_disk, is_zbc, bad_pcode;
 
     dbd = !!(cmd[1] & 0x8);     /* disable block descriptors */
     pcontrol = (cmd[2] & 0xc0) >> 6;
     pcode = cmd[2] & 0x3f;
     subpcode = cmd[3];
     msense_6 = (MODE_SENSE == cmd[0]);
     llbaa = msense_6 ? false : !!(cmd[1] & 0x10);
     is_disk = (sdebug_ptype == TYPE_DISK);
     is_zbc = (devip->zmodel != BLK_ZONED_NONE);
     if ((is_disk || is_zbc) && !dbd)
         bd_len = llbaa ? 16 : 8;
     else
         bd_len = 0;
     alloc_len = msense_6 ? cmd[4] : get_unaligned_be16(cmd + 7);
     memset(arr, 0, SDEBUG_MAX_MSENSE_SZ);
     if (0x3 == pcontrol) {  /* Saving values not supported */
         mk_sense_buffer(scp, ILLEGAL_REQUEST, SAVING_PARAMS_UNSUP, 0);
         return check_condition_result;
     }
     target_dev_id = ((devip->sdbg_host->shost->host_no + 1) * 2000) +
             (devip->target * 1000) - 3;
     /* for disks+zbc set DPOFUA bit and clear write protect (WP) bit */
     if (is_disk || is_zbc) {
         dev_spec = 0x10;    /* =0x90 if WP=1 implies read-only */
         if (sdebug_wp)
             dev_spec |= 0x80;
     } else
         dev_spec = 0x0;
     if (msense_6) {
         arr[2] = dev_spec;
         arr[3] = bd_len;
         offset = 4;
     } else {
         arr[3] = dev_spec;
         if (16 == bd_len)
             arr[4] = 0x1;   /* set LONGLBA bit */
         arr[7] = bd_len;    /* assume 255 or less */
         offset = 8;
     }
     ap = arr + offset;
     if ((bd_len > 0) && (!sdebug_capacity))
         sdebug_capacity = get_sdebug_capacity();
 
     if (8 == bd_len) {
         if (sdebug_capacity > 0xfffffffe)
             put_unaligned_be32(0xffffffff, ap + 0);
         else
             put_unaligned_be32(sdebug_capacity, ap + 0);
         put_unaligned_be16(sdebug_sector_size, ap + 6);
         offset += bd_len;
         ap = arr + offset;
     } else if (16 == bd_len) {
         put_unaligned_be64((u64)sdebug_capacity, ap + 0);
         put_unaligned_be32(sdebug_sector_size, ap + 12);
         offset += bd_len;
         ap = arr + offset;
     }
 
     if ((subpcode > 0x0) && (subpcode < 0xff) && (0x19 != pcode)) {
         /* TODO: Control Extension page */
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
         return check_condition_result;
     }
     bad_pcode = false;
 
     switch (pcode) {
     case 0x1:   /* Read-Write error recovery page, direct access */
         len = resp_err_recov_pg(ap, pcontrol, target);
         offset += len;
         break;
     case 0x2:   /* Disconnect-Reconnect page, all devices */
         len = resp_disconnect_pg(ap, pcontrol, target);
         offset += len;
         break;
     case 0x3:       /* Format device page, direct access */
         if (is_disk) {
             len = resp_format_pg(ap, pcontrol, target);
             offset += len;
         } else
             bad_pcode = true;
         break;
     case 0x8:   /* Caching page, direct access */
         if (is_disk || is_zbc) {
             len = resp_caching_pg(ap, pcontrol, target);
             offset += len;
         } else
             bad_pcode = true;
         break;
     case 0xa:   /* Control Mode page, all devices */
         len = resp_ctrl_m_pg(ap, pcontrol, target);
         offset += len;
         break;
     case 0x19:  /* if spc==1 then sas phy, control+discover */
         if ((subpcode > 0x2) && (subpcode < 0xff)) {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
             return check_condition_result;
         }
         len = 0;
         if ((0x0 == subpcode) || (0xff == subpcode))
             len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
         if ((0x1 == subpcode) || (0xff == subpcode))
             len += resp_sas_pcd_m_spg(ap + len, pcontrol, target,
                           target_dev_id);
         if ((0x2 == subpcode) || (0xff == subpcode))
             len += resp_sas_sha_m_spg(ap + len, pcontrol);
         offset += len;
         break;
     case 0x1c:  /* Informational Exceptions Mode page, all devices */
         len = resp_iec_m_pg(ap, pcontrol, target);
         offset += len;
         break;
     case 0x3f:  /* Read all Mode pages */
         if ((0 == subpcode) || (0xff == subpcode)) {
             len = resp_err_recov_pg(ap, pcontrol, target);
             len += resp_disconnect_pg(ap + len, pcontrol, target);
             if (is_disk) {
                 len += resp_format_pg(ap + len, pcontrol,
                               target);
                 len += resp_caching_pg(ap + len, pcontrol,
                                target);
             } else if (is_zbc) {
                 len += resp_caching_pg(ap + len, pcontrol,
                                target);
             }
             len += resp_ctrl_m_pg(ap + len, pcontrol, target);
             len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
             if (0xff == subpcode) {
                 len += resp_sas_pcd_m_spg(ap + len, pcontrol,
                           target, target_dev_id);
                 len += resp_sas_sha_m_spg(ap + len, pcontrol);
             }
             len += resp_iec_m_pg(ap + len, pcontrol, target);
             offset += len;
         } else {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
             return check_condition_result;
         }
         break;
     default:
         bad_pcode = true;
         break;
     }
     if (bad_pcode) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
         return check_condition_result;
     }
     if (msense_6)
         arr[0] = offset - 1;
     else
         put_unaligned_be16((offset - 2), arr + 0);
     return fill_from_dev_buffer(scp, arr, min_t(u32, alloc_len, offset));
 }
 
 #define SDEBUG_MAX_MSELECT_SZ 512
 
 static int resp_mode_select(struct scsi_cmnd *scp,
                 struct sdebug_dev_info *devip)
 {
     int pf, sp, ps, md_len, bd_len, off, spf, pg_len;
     int param_len, res, mpage;
     unsigned char arr[SDEBUG_MAX_MSELECT_SZ];
     unsigned char *cmd = scp->cmnd;
     int mselect6 = (MODE_SELECT == cmd[0]);
 
     memset(arr, 0, sizeof(arr));
     pf = cmd[1] & 0x10;
     sp = cmd[1] & 0x1;
     param_len = mselect6 ? cmd[4] : get_unaligned_be16(cmd + 7);
     if ((0 == pf) || sp || (param_len > SDEBUG_MAX_MSELECT_SZ)) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, mselect6 ? 4 : 7, -1);
         return check_condition_result;
     }
     res = fetch_to_dev_buffer(scp, arr, param_len);
     if (-1 == res)
         return DID_ERROR << 16;
     else if (sdebug_verbose && (res < param_len))
         sdev_printk(KERN_INFO, scp->device,
                 "%s: cdb indicated=%d, IO sent=%d bytes\n",
                 __func__, param_len, res);
     md_len = mselect6 ? (arr[0] + 1) : (get_unaligned_be16(arr + 0) + 2);
     bd_len = mselect6 ? arr[3] : get_unaligned_be16(arr + 6);
     off = bd_len + (mselect6 ? 4 : 8);
     if (md_len > 2 || off >= res) {
         mk_sense_invalid_fld(scp, SDEB_IN_DATA, 0, -1);
         return check_condition_result;
     }
     mpage = arr[off] & 0x3f;
     ps = !!(arr[off] & 0x80);
     if (ps) {
         mk_sense_invalid_fld(scp, SDEB_IN_DATA, off, 7);
         return check_condition_result;
     }
     spf = !!(arr[off] & 0x40);
     pg_len = spf ? (get_unaligned_be16(arr + off + 2) + 4) :
                (arr[off + 1] + 2);
     if ((pg_len + off) > param_len) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST,
                 PARAMETER_LIST_LENGTH_ERR, 0);
         return check_condition_result;
     }
     switch (mpage) {
     case 0x8:      /* Caching Mode page */
         if (caching_pg[1] == arr[off + 1]) {
             memcpy(caching_pg + 2, arr + off + 2,
                    sizeof(caching_pg) - 2);
             goto set_mode_changed_ua;
         }
         break;
     case 0xa:      /* Control Mode page */
         if (ctrl_m_pg[1] == arr[off + 1]) {
             memcpy(ctrl_m_pg + 2, arr + off + 2,
                    sizeof(ctrl_m_pg) - 2);
             if (ctrl_m_pg[4] & 0x8)
                 sdebug_wp = true;
             else
                 sdebug_wp = false;
             sdebug_dsense = !!(ctrl_m_pg[2] & 0x4);
             goto set_mode_changed_ua;
         }
         break;
     case 0x1c:      /* Informational Exceptions Mode page */
         if (iec_m_pg[1] == arr[off + 1]) {
             memcpy(iec_m_pg + 2, arr + off + 2,
                    sizeof(iec_m_pg) - 2);
             goto set_mode_changed_ua;
         }
         break;
     default:
         break;
     }
     mk_sense_invalid_fld(scp, SDEB_IN_DATA, off, 5);
     return check_condition_result;
 set_mode_changed_ua:
     set_bit(SDEBUG_UA_MODE_CHANGED, devip->uas_bm);
     return 0;
 }
 
 static int resp_temp_l_pg(unsigned char *arr)
 {
     unsigned char temp_l_pg[] = {0x0, 0x0, 0x3, 0x2, 0x0, 38,
                      0x0, 0x1, 0x3, 0x2, 0x0, 65,
         };
 
     memcpy(arr, temp_l_pg, sizeof(temp_l_pg));
     return sizeof(temp_l_pg);
 }
 
 static int resp_ie_l_pg(unsigned char *arr)
 {
     unsigned char ie_l_pg[] = {0x0, 0x0, 0x3, 0x3, 0x0, 0x0, 38,
         };
 
     memcpy(arr, ie_l_pg, sizeof(ie_l_pg));
     if (iec_m_pg[2] & 0x4) {    /* TEST bit set */
         arr[4] = THRESHOLD_EXCEEDED;
         arr[5] = 0xff;
     }
     return sizeof(ie_l_pg);
 }
 
 static int resp_env_rep_l_spg(unsigned char *arr)
 {
     unsigned char env_rep_l_spg[] = {0x0, 0x0, 0x23, 0x8,
                      0x0, 40, 72, 0xff, 45, 18, 0, 0,
                      0x1, 0x0, 0x23, 0x8,
                      0x0, 55, 72, 35, 55, 45, 0, 0,
         };
 
     memcpy(arr, env_rep_l_spg, sizeof(env_rep_l_spg));
     return sizeof(env_rep_l_spg);
 }
 
 #define SDEBUG_MAX_LSENSE_SZ 512
 
 static int resp_log_sense(struct scsi_cmnd *scp,
               struct sdebug_dev_info *devip)
 {
     int ppc, sp, pcode, subpcode;
     u32 alloc_len, len, n;
     unsigned char arr[SDEBUG_MAX_LSENSE_SZ];
     unsigned char *cmd = scp->cmnd;
 
     memset(arr, 0, sizeof(arr));
     ppc = cmd[1] & 0x2;
     sp = cmd[1] & 0x1;
     if (ppc || sp) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, ppc ? 1 : 0);
         return check_condition_result;
     }
     pcode = cmd[2] & 0x3f;
     subpcode = cmd[3] & 0xff;
     alloc_len = get_unaligned_be16(cmd + 7);
     arr[0] = pcode;
     if (0 == subpcode) {
         switch (pcode) {
         case 0x0:   /* Supported log pages log page */
             n = 4;
             arr[n++] = 0x0;     /* this page */
             arr[n++] = 0xd;     /* Temperature */
             arr[n++] = 0x2f;    /* Informational exceptions */
             arr[3] = n - 4;
             break;
         case 0xd:   /* Temperature log page */
             arr[3] = resp_temp_l_pg(arr + 4);
             break;
         case 0x2f:  /* Informational exceptions log page */
             arr[3] = resp_ie_l_pg(arr + 4);
             break;
         default:
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
             return check_condition_result;
         }
     } else if (0xff == subpcode) {
         arr[0] |= 0x40;
         arr[1] = subpcode;
         switch (pcode) {
         case 0x0:   /* Supported log pages and subpages log page */
             n = 4;
             arr[n++] = 0x0;
             arr[n++] = 0x0;     /* 0,0 page */
             arr[n++] = 0x0;
             arr[n++] = 0xff;    /* this page */
             arr[n++] = 0xd;
             arr[n++] = 0x0;     /* Temperature */
             arr[n++] = 0xd;
             arr[n++] = 0x1;     /* Environment reporting */
             arr[n++] = 0xd;
             arr[n++] = 0xff;    /* all 0xd subpages */
             arr[n++] = 0x2f;
             arr[n++] = 0x0; /* Informational exceptions */
             arr[n++] = 0x2f;
             arr[n++] = 0xff;    /* all 0x2f subpages */
             arr[3] = n - 4;
             break;
         case 0xd:   /* Temperature subpages */
             n = 4;
             arr[n++] = 0xd;
             arr[n++] = 0x0;     /* Temperature */
             arr[n++] = 0xd;
             arr[n++] = 0x1;     /* Environment reporting */
             arr[n++] = 0xd;
             arr[n++] = 0xff;    /* these subpages */
             arr[3] = n - 4;
             break;
         case 0x2f:  /* Informational exceptions subpages */
             n = 4;
             arr[n++] = 0x2f;
             arr[n++] = 0x0;     /* Informational exceptions */
             arr[n++] = 0x2f;
             arr[n++] = 0xff;    /* these subpages */
             arr[3] = n - 4;
             break;
         default:
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
             return check_condition_result;
         }
     } else if (subpcode > 0) {
         arr[0] |= 0x40;
         arr[1] = subpcode;
         if (pcode == 0xd && subpcode == 1)
             arr[3] = resp_env_rep_l_spg(arr + 4);
         else {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
             return check_condition_result;
         }
     } else {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
         return check_condition_result;
     }
     len = min_t(u32, get_unaligned_be16(arr + 2) + 4, alloc_len);
     return fill_from_dev_buffer(scp, arr,
             min_t(u32, len, SDEBUG_MAX_INQ_ARR_SZ));
 }
 
 static inline bool sdebug_dev_is_zoned(struct sdebug_dev_info *devip)
 {
     return devip->nr_zones != 0;
 }
 
 static struct sdeb_zone_state *zbc_zone(struct sdebug_dev_info *devip,
                     unsigned long long lba)
 {
     u32 zno = lba >> devip->zsize_shift;
     struct sdeb_zone_state *zsp;
 
     if (devip->zcap == devip->zsize || zno < devip->nr_conv_zones)
         return &devip->zstate[zno];
 
     /*
      * If the zone capacity is less than the zone size, adjust for gap
      * zones.
      */
     zno = 2 * zno - devip->nr_conv_zones;
     WARN_ONCE(zno >= devip->nr_zones, "%u > %u\n", zno, devip->nr_zones);
     zsp = &devip->zstate[zno];
     if (lba >= zsp->z_start + zsp->z_size)
         zsp++;
     WARN_ON_ONCE(lba >= zsp->z_start + zsp->z_size);
     return zsp;
 }
 
 static inline bool zbc_zone_is_conv(struct sdeb_zone_state *zsp)
 {
     return zsp->z_type == ZBC_ZTYPE_CNV;
 }
 
 static inline bool zbc_zone_is_gap(struct sdeb_zone_state *zsp)
 {
     return zsp->z_type == ZBC_ZTYPE_GAP;
 }
 
 static inline bool zbc_zone_is_seq(struct sdeb_zone_state *zsp)
 {
     return !zbc_zone_is_conv(zsp) && !zbc_zone_is_gap(zsp);
 }
 
 static void zbc_close_zone(struct sdebug_dev_info *devip,
                struct sdeb_zone_state *zsp)
 {
     enum sdebug_z_cond zc;
 
     if (!zbc_zone_is_seq(zsp))
         return;
 
     zc = zsp->z_cond;
     if (!(zc == ZC2_IMPLICIT_OPEN || zc == ZC3_EXPLICIT_OPEN))
         return;
 
     if (zc == ZC2_IMPLICIT_OPEN)
         devip->nr_imp_open--;
     else
         devip->nr_exp_open--;
 
     if (zsp->z_wp == zsp->z_start) {
         zsp->z_cond = ZC1_EMPTY;
     } else {
         zsp->z_cond = ZC4_CLOSED;
         devip->nr_closed++;
     }
 }
 
 static void zbc_close_imp_open_zone(struct sdebug_dev_info *devip)
 {
     struct sdeb_zone_state *zsp = &devip->zstate[0];
     unsigned int i;
 
     for (i = 0; i < devip->nr_zones; i++, zsp++) {
         if (zsp->z_cond == ZC2_IMPLICIT_OPEN) {
             zbc_close_zone(devip, zsp);
             return;
         }
     }
 }
 
 static void zbc_open_zone(struct sdebug_dev_info *devip,
               struct sdeb_zone_state *zsp, bool explicit)
 {
     enum sdebug_z_cond zc;
 
     if (!zbc_zone_is_seq(zsp))
         return;
 
     zc = zsp->z_cond;
     if ((explicit && zc == ZC3_EXPLICIT_OPEN) ||
         (!explicit && zc == ZC2_IMPLICIT_OPEN))
         return;
 
     /* Close an implicit open zone if necessary */
     if (explicit && zsp->z_cond == ZC2_IMPLICIT_OPEN)
         zbc_close_zone(devip, zsp);
     else if (devip->max_open &&
          devip->nr_imp_open + devip->nr_exp_open >= devip->max_open)
         zbc_close_imp_open_zone(devip);
 
     if (zsp->z_cond == ZC4_CLOSED)
         devip->nr_closed--;
     if (explicit) {
         zsp->z_cond = ZC3_EXPLICIT_OPEN;
         devip->nr_exp_open++;
     } else {
         zsp->z_cond = ZC2_IMPLICIT_OPEN;
         devip->nr_imp_open++;
     }
 }
 
 static inline void zbc_set_zone_full(struct sdebug_dev_info *devip,
                      struct sdeb_zone_state *zsp)
 {
     switch (zsp->z_cond) {
     case ZC2_IMPLICIT_OPEN:
         devip->nr_imp_open--;
         break;
     case ZC3_EXPLICIT_OPEN:
         devip->nr_exp_open--;
         break;
     default:
         WARN_ONCE(true, "Invalid zone %llu condition %x\n",
               zsp->z_start, zsp->z_cond);
         break;
     }
     zsp->z_cond = ZC5_FULL;
 }
 
 static void zbc_inc_wp(struct sdebug_dev_info *devip,
                unsigned long long lba, unsigned int num)
 {
     struct sdeb_zone_state *zsp = zbc_zone(devip, lba);
     unsigned long long n, end, zend = zsp->z_start + zsp->z_size;
 
     if (!zbc_zone_is_seq(zsp))
         return;
 
     if (zsp->z_type == ZBC_ZTYPE_SWR) {
         zsp->z_wp += num;
         if (zsp->z_wp >= zend)
             zbc_set_zone_full(devip, zsp);
         return;
     }
 
     while (num) {
         if (lba != zsp->z_wp)
             zsp->z_non_seq_resource = true;
 
         end = lba + num;
         if (end >= zend) {
             n = zend - lba;
             zsp->z_wp = zend;
         } else if (end > zsp->z_wp) {
             n = num;
             zsp->z_wp = end;
         } else {
             n = num;
         }
         if (zsp->z_wp >= zend)
             zbc_set_zone_full(devip, zsp);
 
         num -= n;
         lba += n;
         if (num) {
             zsp++;
             zend = zsp->z_start + zsp->z_size;
         }
     }
 }
 
 static int check_zbc_access_params(struct scsi_cmnd *scp,
             unsigned long long lba, unsigned int num, bool write)
 {
     struct scsi_device *sdp = scp->device;
     struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
     struct sdeb_zone_state *zsp = zbc_zone(devip, lba);
     struct sdeb_zone_state *zsp_end = zbc_zone(devip, lba + num - 1);
 
     if (!write) {
         if (devip->zmodel == BLK_ZONED_HA)
             return 0;
         /* For host-managed, reads cannot cross zone types boundaries */
         if (zsp->z_type != zsp_end->z_type) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     LBA_OUT_OF_RANGE,
                     READ_INVDATA_ASCQ);
             return check_condition_result;
         }
         return 0;
     }
 
     /* Writing into a gap zone is not allowed */
     if (zbc_zone_is_gap(zsp)) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE,
                 ATTEMPT_ACCESS_GAP);
         return check_condition_result;
     }
 
     /* No restrictions for writes within conventional zones */
     if (zbc_zone_is_conv(zsp)) {
         if (!zbc_zone_is_conv(zsp_end)) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     LBA_OUT_OF_RANGE,
                     WRITE_BOUNDARY_ASCQ);
             return check_condition_result;
         }
         return 0;
     }
 
     if (zsp->z_type == ZBC_ZTYPE_SWR) {
         /* Writes cannot cross sequential zone boundaries */
         if (zsp_end != zsp) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     LBA_OUT_OF_RANGE,
                     WRITE_BOUNDARY_ASCQ);
             return check_condition_result;
         }
         /* Cannot write full zones */
         if (zsp->z_cond == ZC5_FULL) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     INVALID_FIELD_IN_CDB, 0);
             return check_condition_result;
         }
         /* Writes must be aligned to the zone WP */
         if (lba != zsp->z_wp) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     LBA_OUT_OF_RANGE,
                     UNALIGNED_WRITE_ASCQ);
             return check_condition_result;
         }
     }
 
     /* Handle implicit open of closed and empty zones */
     if (zsp->z_cond == ZC1_EMPTY || zsp->z_cond == ZC4_CLOSED) {
         if (devip->max_open &&
             devip->nr_exp_open >= devip->max_open) {
             mk_sense_buffer(scp, DATA_PROTECT,
                     INSUFF_RES_ASC,
                     INSUFF_ZONE_ASCQ);
             return check_condition_result;
         }
         zbc_open_zone(devip, zsp, false);
     }
 
     return 0;
 }
 
 static inline int check_device_access_params
             (struct scsi_cmnd *scp, unsigned long long lba,
              unsigned int num, bool write)
 {
     struct scsi_device *sdp = scp->device;
     struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
 
     if (lba + num > sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         return check_condition_result;
     }
     /* transfer length excessive (tie in to block limits VPD page) */
     if (num > sdebug_store_sectors) {
         /* needs work to find which cdb byte 'num' comes from */
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         return check_condition_result;
     }
     if (write && unlikely(sdebug_wp)) {
         mk_sense_buffer(scp, DATA_PROTECT, WRITE_PROTECTED, 0x2);
         return check_condition_result;
     }
     if (sdebug_dev_is_zoned(devip))
         return check_zbc_access_params(scp, lba, num, write);
 
     return 0;
 }
 
 /*
  * Note: if BUG_ON() fires it usually indicates a problem with the parser
  * tables. Perhaps a missing F_FAKE_RW or FF_MEDIA_IO flag. Response functions
  * that access any of the "stores" in struct sdeb_store_info should call this
  * function with bug_if_fake_rw set to true.
  */
 static inline struct sdeb_store_info *devip2sip(struct sdebug_dev_info *devip,
                         bool bug_if_fake_rw)
 {
     if (sdebug_fake_rw) {
         BUG_ON(bug_if_fake_rw); /* See note above */
         return NULL;
     }
     return xa_load(per_store_ap, devip->sdbg_host->si_idx);
 }
 
 /* Returns number of bytes copied or -1 if error. */
 static int do_device_access(struct sdeb_store_info *sip, struct scsi_cmnd *scp,
                 u32 sg_skip, u64 lba, u32 num, bool do_write)
 {
     int ret;
     u64 block, rest = 0;
     enum dma_data_direction dir;
     struct scsi_data_buffer *sdb = &scp->sdb;
     u8 *fsp;
 
     if (do_write) {
         dir = DMA_TO_DEVICE;
         write_since_sync = true;
     } else {
         dir = DMA_FROM_DEVICE;
     }
 
     if (!sdb->length || !sip)
         return 0;
     if (scp->sc_data_direction != dir)
         return -1;
     fsp = sip->storep;
 
     block = do_div(lba, sdebug_store_sectors);
     if (block + num > sdebug_store_sectors)
         rest = block + num - sdebug_store_sectors;
 
     ret = sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
            fsp + (block * sdebug_sector_size),
            (num - rest) * sdebug_sector_size, sg_skip, do_write);
     if (ret != (num - rest) * sdebug_sector_size)
         return ret;
 
     if (rest) {
         ret += sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
                 fsp, rest * sdebug_sector_size,
                 sg_skip + ((num - rest) * sdebug_sector_size),
                 do_write);
     }
 
     return ret;
 }
 
 /* Returns number of bytes copied or -1 if error. */
 static int do_dout_fetch(struct scsi_cmnd *scp, u32 num, u8 *doutp)
 {
     struct scsi_data_buffer *sdb = &scp->sdb;
 
     if (!sdb->length)
         return 0;
     if (scp->sc_data_direction != DMA_TO_DEVICE)
         return -1;
     return sg_copy_buffer(sdb->table.sgl, sdb->table.nents, doutp,
                   num * sdebug_sector_size, 0, true);
 }
 
 /* If sip->storep+lba compares equal to arr(num), then copy top half of
  * arr into sip->storep+lba and return true. If comparison fails then
  * return false. */
 static bool comp_write_worker(struct sdeb_store_info *sip, u64 lba, u32 num,
                   const u8 *arr, bool compare_only)
 {
     bool res;
     u64 block, rest = 0;
     u32 store_blks = sdebug_store_sectors;
     u32 lb_size = sdebug_sector_size;
     u8 *fsp = sip->storep;
 
     block = do_div(lba, store_blks);
     if (block + num > store_blks)
         rest = block + num - store_blks;
 
     res = !memcmp(fsp + (block * lb_size), arr, (num - rest) * lb_size);
     if (!res)
         return res;
     if (rest)
         res = memcmp(fsp, arr + ((num - rest) * lb_size),
                  rest * lb_size);
     if (!res)
         return res;
     if (compare_only)
         return true;
     arr += num * lb_size;
     memcpy(fsp + (block * lb_size), arr, (num - rest) * lb_size);
     if (rest)
         memcpy(fsp, arr + ((num - rest) * lb_size), rest * lb_size);
     return res;
 }
 
 static __be16 dif_compute_csum(const void *buf, int len)
 {
     __be16 csum;
 
     if (sdebug_guard)
         csum = (__force __be16)ip_compute_csum(buf, len);
     else
         csum = cpu_to_be16(crc_t10dif(buf, len));
 
     return csum;
 }
 
 static int dif_verify(struct t10_pi_tuple *sdt, const void *data,
               sector_t sector, u32 ei_lba)
 {
     __be16 csum = dif_compute_csum(data, sdebug_sector_size);
 
     if (sdt->guard_tag != csum) {
         pr_err("GUARD check failed on sector %lu rcvd 0x%04x, data 0x%04x\n",
             (unsigned long)sector,
             be16_to_cpu(sdt->guard_tag),
             be16_to_cpu(csum));
         return 0x01;
     }
     if (sdebug_dif == T10_PI_TYPE1_PROTECTION &&
         be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
         pr_err("REF check failed on sector %lu\n",
             (unsigned long)sector);
         return 0x03;
     }
     if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
         be32_to_cpu(sdt->ref_tag) != ei_lba) {
         pr_err("REF check failed on sector %lu\n",
             (unsigned long)sector);
         return 0x03;
     }
     return 0;
 }
 
 static void dif_copy_prot(struct scsi_cmnd *scp, sector_t sector,
               unsigned int sectors, bool read)
 {
     size_t resid;
     void *paddr;
     struct sdeb_store_info *sip = devip2sip((struct sdebug_dev_info *)
                         scp->device->hostdata, true);
     struct t10_pi_tuple *dif_storep = sip->dif_storep;
     const void *dif_store_end = dif_storep + sdebug_store_sectors;
     struct sg_mapping_iter miter;
 
     /* Bytes of protection data to copy into sgl */
     resid = sectors * sizeof(*dif_storep);
 
     sg_miter_start(&miter, scsi_prot_sglist(scp),
                scsi_prot_sg_count(scp), SG_MITER_ATOMIC |
                (read ? SG_MITER_TO_SG : SG_MITER_FROM_SG));
 
     while (sg_miter_next(&miter) && resid > 0) {
         size_t len = min_t(size_t, miter.length, resid);
         void *start = dif_store(sip, sector);
         size_t rest = 0;
 
         if (dif_store_end < start + len)
             rest = start + len - dif_store_end;
 
         paddr = miter.addr;
 
         if (read)
             memcpy(paddr, start, len - rest);
         else
             memcpy(start, paddr, len - rest);
 
         if (rest) {
             if (read)
                 memcpy(paddr + len - rest, dif_storep, rest);
             else
                 memcpy(dif_storep, paddr + len - rest, rest);
         }
 
         sector += len / sizeof(*dif_storep);
         resid -= len;
     }
     sg_miter_stop(&miter);
 }
 
 static int prot_verify_read(struct scsi_cmnd *scp, sector_t start_sec,
                 unsigned int sectors, u32 ei_lba)
 {
     int ret = 0;
     unsigned int i;
     sector_t sector;
     struct sdeb_store_info *sip = devip2sip((struct sdebug_dev_info *)
                         scp->device->hostdata, true);
     struct t10_pi_tuple *sdt;
 
     for (i = 0; i < sectors; i++, ei_lba++) {
         sector = start_sec + i;
         sdt = dif_store(sip, sector);
 
         if (sdt->app_tag == cpu_to_be16(0xffff))
             continue;
 
         /*
          * Because scsi_debug acts as both initiator and
          * target we proceed to verify the PI even if
          * RDPROTECT=3. This is done so the "initiator" knows
          * which type of error to return. Otherwise we would
          * have to iterate over the PI twice.
          */
         if (scp->cmnd[1] >> 5) { /* RDPROTECT */
             ret = dif_verify(sdt, lba2fake_store(sip, sector),
                      sector, ei_lba);
             if (ret) {
                 dif_errors++;
                 break;
             }
         }
     }
 
     dif_copy_prot(scp, start_sec, sectors, true);
     dix_reads++;
 
     return ret;
 }
 
 static inline void
 sdeb_read_lock(struct sdeb_store_info *sip)
 {
     if (sdebug_no_rwlock) {
         if (sip)
             __acquire(&sip->macc_lck);
         else
             __acquire(&sdeb_fake_rw_lck);
     } else {
         if (sip)
             read_lock(&sip->macc_lck);
         else
             read_lock(&sdeb_fake_rw_lck);
     }
 }
 
 static inline void
 sdeb_read_unlock(struct sdeb_store_info *sip)
 {
     if (sdebug_no_rwlock) {
         if (sip)
             __release(&sip->macc_lck);
         else
             __release(&sdeb_fake_rw_lck);
     } else {
         if (sip)
             read_unlock(&sip->macc_lck);
         else
             read_unlock(&sdeb_fake_rw_lck);
     }
 }
 
 static inline void
 sdeb_write_lock(struct sdeb_store_info *sip)
 {
     if (sdebug_no_rwlock) {
         if (sip)
             __acquire(&sip->macc_lck);
         else
             __acquire(&sdeb_fake_rw_lck);
     } else {
         if (sip)
             write_lock(&sip->macc_lck);
         else
             write_lock(&sdeb_fake_rw_lck);
     }
 }
 
 static inline void
 sdeb_write_unlock(struct sdeb_store_info *sip)
 {
     if (sdebug_no_rwlock) {
         if (sip)
             __release(&sip->macc_lck);
         else
             __release(&sdeb_fake_rw_lck);
     } else {
         if (sip)
             write_unlock(&sip->macc_lck);
         else
             write_unlock(&sdeb_fake_rw_lck);
     }
 }
 
 static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     bool check_prot;
     u32 num;
     u32 ei_lba;
     int ret;
     u64 lba;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     u8 *cmd = scp->cmnd;
 
     switch (cmd[0]) {
     case READ_16:
         ei_lba = 0;
         lba = get_unaligned_be64(cmd + 2);
         num = get_unaligned_be32(cmd + 10);
         check_prot = true;
         break;
     case READ_10:
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be16(cmd + 7);
         check_prot = true;
         break;
     case READ_6:
         ei_lba = 0;
         lba = (u32)cmd[3] | (u32)cmd[2] << 8 |
               (u32)(cmd[1] & 0x1f) << 16;
         num = (0 == cmd[4]) ? 256 : cmd[4];
         check_prot = true;
         break;
     case READ_12:
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be32(cmd + 6);
         check_prot = true;
         break;
     case XDWRITEREAD_10:
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be16(cmd + 7);
         check_prot = false;
         break;
     default:    /* assume READ(32) */
         lba = get_unaligned_be64(cmd + 12);
         ei_lba = get_unaligned_be32(cmd + 20);
         num = get_unaligned_be32(cmd + 28);
         check_prot = false;
         break;
     }
     if (unlikely(have_dif_prot && check_prot)) {
         if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
             (cmd[1] & 0xe0)) {
             mk_sense_invalid_opcode(scp);
             return check_condition_result;
         }
         if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
              sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
             (cmd[1] & 0xe0) == 0)
             sdev_printk(KERN_ERR, scp->device, "Unprotected RD "
                     "to DIF device\n");
     }
     if (unlikely((sdebug_opts & SDEBUG_OPT_SHORT_TRANSFER) &&
              atomic_read(&sdeb_inject_pending))) {
         num /= 2;
         atomic_set(&sdeb_inject_pending, 0);
     }
 
     ret = check_device_access_params(scp, lba, num, false);
     if (ret)
         return ret;
     if (unlikely((SDEBUG_OPT_MEDIUM_ERR & sdebug_opts) &&
              (lba <= (sdebug_medium_error_start + sdebug_medium_error_count - 1)) &&
              ((lba + num) > sdebug_medium_error_start))) {
         /* claim unrecoverable read error */
         mk_sense_buffer(scp, MEDIUM_ERROR, UNRECOVERED_READ_ERR, 0);
         /* set info field and valid bit for fixed descriptor */
         if (0x70 == (scp->sense_buffer[0] & 0x7f)) {
             scp->sense_buffer[0] |= 0x80;   /* Valid bit */
             ret = (lba < OPT_MEDIUM_ERR_ADDR)
                   ? OPT_MEDIUM_ERR_ADDR : (int)lba;
             put_unaligned_be32(ret, scp->sense_buffer + 3);
         }
         scsi_set_resid(scp, scsi_bufflen(scp));
         return check_condition_result;
     }
 
     sdeb_read_lock(sip);
 
     /* DIX + T10 DIF */
     if (unlikely(sdebug_dix && scsi_prot_sg_count(scp))) {
         switch (prot_verify_read(scp, lba, num, ei_lba)) {
         case 1: /* Guard tag error */
             if (cmd[1] >> 5 != 3) { /* RDPROTECT != 3 */
                 sdeb_read_unlock(sip);
                 mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
                 return check_condition_result;
             } else if (scp->prot_flags & SCSI_PROT_GUARD_CHECK) {
                 sdeb_read_unlock(sip);
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
                 return illegal_condition_result;
             }
             break;
         case 3: /* Reference tag error */
             if (cmd[1] >> 5 != 3) { /* RDPROTECT != 3 */
                 sdeb_read_unlock(sip);
                 mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 3);
                 return check_condition_result;
             } else if (scp->prot_flags & SCSI_PROT_REF_CHECK) {
                 sdeb_read_unlock(sip);
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 3);
                 return illegal_condition_result;
             }
             break;
         }
     }
 
     ret = do_device_access(sip, scp, 0, lba, num, false);
     sdeb_read_unlock(sip);
     if (unlikely(ret == -1))
         return DID_ERROR << 16;
 
     scsi_set_resid(scp, scsi_bufflen(scp) - ret);
 
     if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
              atomic_read(&sdeb_inject_pending))) {
         if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
             mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
             atomic_set(&sdeb_inject_pending, 0);
             return check_condition_result;
         } else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
             /* Logical block guard check failed */
             mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
             atomic_set(&sdeb_inject_pending, 0);
             return illegal_condition_result;
         } else if (SDEBUG_OPT_DIX_ERR & sdebug_opts) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
             atomic_set(&sdeb_inject_pending, 0);
             return illegal_condition_result;
         }
     }
     return 0;
 }
 
 static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
                  unsigned int sectors, u32 ei_lba)
 {
     int ret;
     struct t10_pi_tuple *sdt;
     void *daddr;
     sector_t sector = start_sec;
     int ppage_offset;
     int dpage_offset;
     struct sg_mapping_iter diter;
     struct sg_mapping_iter piter;
 
     BUG_ON(scsi_sg_count(SCpnt) == 0);
     BUG_ON(scsi_prot_sg_count(SCpnt) == 0);
 
     sg_miter_start(&piter, scsi_prot_sglist(SCpnt),
             scsi_prot_sg_count(SCpnt),
             SG_MITER_ATOMIC | SG_MITER_FROM_SG);
     sg_miter_start(&diter, scsi_sglist(SCpnt), scsi_sg_count(SCpnt),
             SG_MITER_ATOMIC | SG_MITER_FROM_SG);
 
     /* For each protection page */
     while (sg_miter_next(&piter)) {
         dpage_offset = 0;
         if (WARN_ON(!sg_miter_next(&diter))) {
             ret = 0x01;
             goto out;
         }
 
         for (ppage_offset = 0; ppage_offset < piter.length;
              ppage_offset += sizeof(struct t10_pi_tuple)) {
             /* If we're at the end of the current
              * data page advance to the next one
              */
             if (dpage_offset >= diter.length) {
                 if (WARN_ON(!sg_miter_next(&diter))) {
                     ret = 0x01;
                     goto out;
                 }
                 dpage_offset = 0;
             }
 
             sdt = piter.addr + ppage_offset;
             daddr = diter.addr + dpage_offset;
 
             if (SCpnt->cmnd[1] >> 5 != 3) { /* WRPROTECT */
                 ret = dif_verify(sdt, daddr, sector, ei_lba);
                 if (ret)
                     goto out;
             }
 
             sector++;
             ei_lba++;
             dpage_offset += sdebug_sector_size;
         }
         diter.consumed = dpage_offset;
         sg_miter_stop(&diter);
     }
     sg_miter_stop(&piter);
 
     dif_copy_prot(SCpnt, start_sec, sectors, false);
     dix_writes++;
 
     return 0;
 
 out:
     dif_errors++;
     sg_miter_stop(&diter);
     sg_miter_stop(&piter);
     return ret;
 }
 
 static unsigned long lba_to_map_index(sector_t lba)
 {
     if (sdebug_unmap_alignment)
         lba += sdebug_unmap_granularity - sdebug_unmap_alignment;
     sector_div(lba, sdebug_unmap_granularity);
     return lba;
 }
 
 static sector_t map_index_to_lba(unsigned long index)
 {
     sector_t lba = index * sdebug_unmap_granularity;
 
     if (sdebug_unmap_alignment)
         lba -= sdebug_unmap_granularity - sdebug_unmap_alignment;
     return lba;
 }
 
 static unsigned int map_state(struct sdeb_store_info *sip, sector_t lba,
                   unsigned int *num)
 {
     sector_t end;
     unsigned int mapped;
     unsigned long index;
     unsigned long next;
 
     index = lba_to_map_index(lba);
     mapped = test_bit(index, sip->map_storep);
 
     if (mapped)
         next = find_next_zero_bit(sip->map_storep, map_size, index);
     else
         next = find_next_bit(sip->map_storep, map_size, index);
 
     end = min_t(sector_t, sdebug_store_sectors,  map_index_to_lba(next));
     *num = end - lba;
     return mapped;
 }
 
 static void map_region(struct sdeb_store_info *sip, sector_t lba,
                unsigned int len)
 {
     sector_t end = lba + len;
 
     while (lba < end) {
         unsigned long index = lba_to_map_index(lba);
 
         if (index < map_size)
             set_bit(index, sip->map_storep);
 
         lba = map_index_to_lba(index + 1);
     }
 }
 
 static void unmap_region(struct sdeb_store_info *sip, sector_t lba,
              unsigned int len)
 {
     sector_t end = lba + len;
     u8 *fsp = sip->storep;
 
     while (lba < end) {
         unsigned long index = lba_to_map_index(lba);
 
         if (lba == map_index_to_lba(index) &&
             lba + sdebug_unmap_granularity <= end &&
             index < map_size) {
             clear_bit(index, sip->map_storep);
             if (sdebug_lbprz) {  /* for LBPRZ=2 return 0xff_s */
                 memset(fsp + lba * sdebug_sector_size,
                        (sdebug_lbprz & 1) ? 0 : 0xff,
                        sdebug_sector_size *
                        sdebug_unmap_granularity);
             }
             if (sip->dif_storep) {
                 memset(sip->dif_storep + lba, 0xff,
                        sizeof(*sip->dif_storep) *
                        sdebug_unmap_granularity);
             }
         }
         lba = map_index_to_lba(index + 1);
     }
 }
 
 static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     bool check_prot;
     u32 num;
     u32 ei_lba;
     int ret;
     u64 lba;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     u8 *cmd = scp->cmnd;
 
     switch (cmd[0]) {
     case WRITE_16:
         ei_lba = 0;
         lba = get_unaligned_be64(cmd + 2);
         num = get_unaligned_be32(cmd + 10);
         check_prot = true;
         break;
     case WRITE_10:
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be16(cmd + 7);
         check_prot = true;
         break;
     case WRITE_6:
         ei_lba = 0;
         lba = (u32)cmd[3] | (u32)cmd[2] << 8 |
               (u32)(cmd[1] & 0x1f) << 16;
         num = (0 == cmd[4]) ? 256 : cmd[4];
         check_prot = true;
         break;
     case WRITE_12:
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be32(cmd + 6);
         check_prot = true;
         break;
     case 0x53:  /* XDWRITEREAD(10) */
         ei_lba = 0;
         lba = get_unaligned_be32(cmd + 2);
         num = get_unaligned_be16(cmd + 7);
         check_prot = false;
         break;
     default:    /* assume WRITE(32) */
         lba = get_unaligned_be64(cmd + 12);
         ei_lba = get_unaligned_be32(cmd + 20);
         num = get_unaligned_be32(cmd + 28);
         check_prot = false;
         break;
     }
     if (unlikely(have_dif_prot && check_prot)) {
         if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
             (cmd[1] & 0xe0)) {
             mk_sense_invalid_opcode(scp);
             return check_condition_result;
         }
         if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
              sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
             (cmd[1] & 0xe0) == 0)
             sdev_printk(KERN_ERR, scp->device, "Unprotected WR "
                     "to DIF device\n");
     }
 
     sdeb_write_lock(sip);
     ret = check_device_access_params(scp, lba, num, true);
     if (ret) {
         sdeb_write_unlock(sip);
         return ret;
     }
 
     /* DIX + T10 DIF */
     if (unlikely(sdebug_dix && scsi_prot_sg_count(scp))) {
         switch (prot_verify_write(scp, lba, num, ei_lba)) {
         case 1: /* Guard tag error */
             if (scp->prot_flags & SCSI_PROT_GUARD_CHECK) {
                 sdeb_write_unlock(sip);
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
                 return illegal_condition_result;
             } else if (scp->cmnd[1] >> 5 != 3) { /* WRPROTECT != 3 */
                 sdeb_write_unlock(sip);
                 mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
                 return check_condition_result;
             }
             break;
         case 3: /* Reference tag error */
             if (scp->prot_flags & SCSI_PROT_REF_CHECK) {
                 sdeb_write_unlock(sip);
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 3);
                 return illegal_condition_result;
             } else if (scp->cmnd[1] >> 5 != 3) { /* WRPROTECT != 3 */
                 sdeb_write_unlock(sip);
                 mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 3);
                 return check_condition_result;
             }
             break;
         }
     }
 
     ret = do_device_access(sip, scp, 0, lba, num, true);
     if (unlikely(scsi_debug_lbp()))
         map_region(sip, lba, num);
     /* If ZBC zone then bump its write pointer */
     if (sdebug_dev_is_zoned(devip))
         zbc_inc_wp(devip, lba, num);
     sdeb_write_unlock(sip);
     if (unlikely(-1 == ret))
         return DID_ERROR << 16;
     else if (unlikely(sdebug_verbose &&
               (ret < (num * sdebug_sector_size))))
         sdev_printk(KERN_INFO, scp->device,
                 "%s: write: cdb indicated=%u, IO sent=%d bytes\n",
                 my_name, num * sdebug_sector_size, ret);
 
     if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
              atomic_read(&sdeb_inject_pending))) {
         if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
             mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
             atomic_set(&sdeb_inject_pending, 0);
             return check_condition_result;
         } else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
             /* Logical block guard check failed */
             mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
             atomic_set(&sdeb_inject_pending, 0);
             return illegal_condition_result;
         } else if (sdebug_opts & SDEBUG_OPT_DIX_ERR) {
             mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
             atomic_set(&sdeb_inject_pending, 0);
             return illegal_condition_result;
         }
     }
     return 0;
 }
 
 /*
  * T10 has only specified WRITE SCATTERED(16) and WRITE SCATTERED(32).
  * No READ GATHERED yet (requires bidi or long cdb holding gather list).
  */
 static int resp_write_scat(struct scsi_cmnd *scp,
                struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     u8 *lrdp = NULL;
     u8 *up;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     u8 wrprotect;
     u16 lbdof, num_lrd, k;
     u32 num, num_by, bt_len, lbdof_blen, sg_off, cum_lb;
     u32 lb_size = sdebug_sector_size;
     u32 ei_lba;
     u64 lba;
     int ret, res;
     bool is_16;
     static const u32 lrd_size = 32; /* + parameter list header size */
 
     if (cmd[0] == VARIABLE_LENGTH_CMD) {
         is_16 = false;
         wrprotect = (cmd[10] >> 5) & 0x7;
         lbdof = get_unaligned_be16(cmd + 12);
         num_lrd = get_unaligned_be16(cmd + 16);
         bt_len = get_unaligned_be32(cmd + 28);
     } else {        /* that leaves WRITE SCATTERED(16) */
         is_16 = true;
         wrprotect = (cmd[2] >> 5) & 0x7;
         lbdof = get_unaligned_be16(cmd + 4);
         num_lrd = get_unaligned_be16(cmd + 8);
         bt_len = get_unaligned_be32(cmd + 10);
         if (unlikely(have_dif_prot)) {
             if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
                 wrprotect) {
                 mk_sense_invalid_opcode(scp);
                 return illegal_condition_result;
             }
             if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
                  sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
                  wrprotect == 0)
                 sdev_printk(KERN_ERR, scp->device,
                         "Unprotected WR to DIF device\n");
         }
     }
     if ((num_lrd == 0) || (bt_len == 0))
         return 0;       /* T10 says these do-nothings are not errors */
     if (lbdof == 0) {
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, scp->device,
                 "%s: %s: LB Data Offset field bad\n",
                 my_name, __func__);
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         return illegal_condition_result;
     }
     lbdof_blen = lbdof * lb_size;
     if ((lrd_size + (num_lrd * lrd_size)) > lbdof_blen) {
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, scp->device,
                 "%s: %s: LBA range descriptors don't fit\n",
                 my_name, __func__);
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         return illegal_condition_result;
     }
     lrdp = kzalloc(lbdof_blen, GFP_ATOMIC);
     if (lrdp == NULL)
         return SCSI_MLQUEUE_HOST_BUSY;
     if (sdebug_verbose)
         sdev_printk(KERN_INFO, scp->device,
             "%s: %s: Fetch header+scatter_list, lbdof_blen=%u\n",
             my_name, __func__, lbdof_blen);
     res = fetch_to_dev_buffer(scp, lrdp, lbdof_blen);
     if (res == -1) {
         ret = DID_ERROR << 16;
         goto err_out;
     }
 
     sdeb_write_lock(sip);
     sg_off = lbdof_blen;
     /* Spec says Buffer xfer Length field in number of LBs in dout */
     cum_lb = 0;
     for (k = 0, up = lrdp + lrd_size; k < num_lrd; ++k, up += lrd_size) {
         lba = get_unaligned_be64(up + 0);
         num = get_unaligned_be32(up + 8);
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, scp->device,
                 "%s: %s: k=%d  LBA=0x%llx num=%u  sg_off=%u\n",
                 my_name, __func__, k, lba, num, sg_off);
         if (num == 0)
             continue;
         ret = check_device_access_params(scp, lba, num, true);
         if (ret)
             goto err_out_unlock;
         num_by = num * lb_size;
         ei_lba = is_16 ? 0 : get_unaligned_be32(up + 12);
 
         if ((cum_lb + num) > bt_len) {
             if (sdebug_verbose)
                 sdev_printk(KERN_INFO, scp->device,
                     "%s: %s: sum of blocks > data provided\n",
                     my_name, __func__);
             mk_sense_buffer(scp, ILLEGAL_REQUEST, WRITE_ERROR_ASC,
                     0);
             ret = illegal_condition_result;
             goto err_out_unlock;
         }
 
         /* DIX + T10 DIF */
         if (unlikely(sdebug_dix && scsi_prot_sg_count(scp))) {
             int prot_ret = prot_verify_write(scp, lba, num,
                              ei_lba);
 
             if (prot_ret) {
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10,
                         prot_ret);
                 ret = illegal_condition_result;
                 goto err_out_unlock;
             }
         }
 
         ret = do_device_access(sip, scp, sg_off, lba, num, true);
         /* If ZBC zone then bump its write pointer */
         if (sdebug_dev_is_zoned(devip))
             zbc_inc_wp(devip, lba, num);
         if (unlikely(scsi_debug_lbp()))
             map_region(sip, lba, num);
         if (unlikely(-1 == ret)) {
             ret = DID_ERROR << 16;
             goto err_out_unlock;
         } else if (unlikely(sdebug_verbose && (ret < num_by)))
             sdev_printk(KERN_INFO, scp->device,
                 "%s: write: cdb indicated=%u, IO sent=%d bytes\n",
                 my_name, num_by, ret);
 
         if (unlikely((sdebug_opts & SDEBUG_OPT_RECOV_DIF_DIX) &&
                  atomic_read(&sdeb_inject_pending))) {
             if (sdebug_opts & SDEBUG_OPT_RECOVERED_ERR) {
                 mk_sense_buffer(scp, RECOVERED_ERROR, THRESHOLD_EXCEEDED, 0);
                 atomic_set(&sdeb_inject_pending, 0);
                 ret = check_condition_result;
                 goto err_out_unlock;
             } else if (sdebug_opts & SDEBUG_OPT_DIF_ERR) {
                 /* Logical block guard check failed */
                 mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
                 atomic_set(&sdeb_inject_pending, 0);
                 ret = illegal_condition_result;
                 goto err_out_unlock;
             } else if (sdebug_opts & SDEBUG_OPT_DIX_ERR) {
                 mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
                 atomic_set(&sdeb_inject_pending, 0);
                 ret = illegal_condition_result;
                 goto err_out_unlock;
             }
         }
         sg_off += num_by;
         cum_lb += num;
     }
     ret = 0;
 err_out_unlock:
     sdeb_write_unlock(sip);
 err_out:
     kfree(lrdp);
     return ret;
 }
 
 static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num,
                u32 ei_lba, bool unmap, bool ndob)
 {
     struct scsi_device *sdp = scp->device;
     struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
     unsigned long long i;
     u64 block, lbaa;
     u32 lb_size = sdebug_sector_size;
     int ret;
     struct sdeb_store_info *sip = devip2sip((struct sdebug_dev_info *)
                         scp->device->hostdata, true);
     u8 *fs1p;
     u8 *fsp;
 
     sdeb_write_lock(sip);
 
     ret = check_device_access_params(scp, lba, num, true);
     if (ret) {
         sdeb_write_unlock(sip);
         return ret;
     }
 
     if (unmap && scsi_debug_lbp()) {
         unmap_region(sip, lba, num);
         goto out;
     }
     lbaa = lba;
     block = do_div(lbaa, sdebug_store_sectors);
     /* if ndob then zero 1 logical block, else fetch 1 logical block */
     fsp = sip->storep;
     fs1p = fsp + (block * lb_size);
     if (ndob) {
         memset(fs1p, 0, lb_size);
         ret = 0;
     } else
         ret = fetch_to_dev_buffer(scp, fs1p, lb_size);
 
     if (-1 == ret) {
         sdeb_write_unlock(sip);
         return DID_ERROR << 16;
     } else if (sdebug_verbose && !ndob && (ret < lb_size))
         sdev_printk(KERN_INFO, scp->device,
                 "%s: %s: lb size=%u, IO sent=%d bytes\n",
                 my_name, "write same", lb_size, ret);
 
     /* Copy first sector to remaining blocks */
     for (i = 1 ; i < num ; i++) {
         lbaa = lba + i;
         block = do_div(lbaa, sdebug_store_sectors);
         memmove(fsp + (block * lb_size), fs1p, lb_size);
     }
     if (scsi_debug_lbp())
         map_region(sip, lba, num);
     /* If ZBC zone then bump its write pointer */
     if (sdebug_dev_is_zoned(devip))
         zbc_inc_wp(devip, lba, num);
 out:
     sdeb_write_unlock(sip);
 
     return 0;
 }
 
 static int resp_write_same_10(struct scsi_cmnd *scp,
                   struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     u32 lba;
     u16 num;
     u32 ei_lba = 0;
     bool unmap = false;
 
     if (cmd[1] & 0x8) {
         if (sdebug_lbpws10 == 0) {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 3);
             return check_condition_result;
         } else
             unmap = true;
     }
     lba = get_unaligned_be32(cmd + 2);
     num = get_unaligned_be16(cmd + 7);
     if (num > sdebug_write_same_length) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 7, -1);
         return check_condition_result;
     }
     return resp_write_same(scp, lba, num, ei_lba, unmap, false);
 }
 
 static int resp_write_same_16(struct scsi_cmnd *scp,
                   struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     u64 lba;
     u32 num;
     u32 ei_lba = 0;
     bool unmap = false;
     bool ndob = false;
 
     if (cmd[1] & 0x8) { /* UNMAP */
         if (sdebug_lbpws == 0) {
             mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 3);
             return check_condition_result;
         } else
             unmap = true;
     }
     if (cmd[1] & 0x1)  /* NDOB (no data-out buffer, assumes zeroes) */
         ndob = true;
     lba = get_unaligned_be64(cmd + 2);
     num = get_unaligned_be32(cmd + 10);
     if (num > sdebug_write_same_length) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 10, -1);
         return check_condition_result;
     }
     return resp_write_same(scp, lba, num, ei_lba, unmap, ndob);
 }
 
 /* Note the mode field is in the same position as the (lower) service action
  * field. For the Report supported operation codes command, SPC-4 suggests
  * each mode of this command should be reported separately; for future. */
 static int resp_write_buffer(struct scsi_cmnd *scp,
                  struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     struct scsi_device *sdp = scp->device;
     struct sdebug_dev_info *dp;
     u8 mode;
 
     mode = cmd[1] & 0x1f;
     switch (mode) {
     case 0x4:   /* download microcode (MC) and activate (ACT) */
         /* set UAs on this device only */
         set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
         set_bit(SDEBUG_UA_MICROCODE_CHANGED, devip->uas_bm);
         break;
     case 0x5:   /* download MC, save and ACT */
         set_bit(SDEBUG_UA_MICROCODE_CHANGED_WO_RESET, devip->uas_bm);
         break;
     case 0x6:   /* download MC with offsets and ACT */
         /* set UAs on most devices (LUs) in this target */
         list_for_each_entry(dp,
                     &devip->sdbg_host->dev_info_list,
                     dev_list)
             if (dp->target == sdp->id) {
                 set_bit(SDEBUG_UA_BUS_RESET, dp->uas_bm);
                 if (devip != dp)
                     set_bit(SDEBUG_UA_MICROCODE_CHANGED,
                         dp->uas_bm);
             }
         break;
     case 0x7:   /* download MC with offsets, save, and ACT */
         /* set UA on all devices (LUs) in this target */
         list_for_each_entry(dp,
                     &devip->sdbg_host->dev_info_list,
                     dev_list)
             if (dp->target == sdp->id)
                 set_bit(SDEBUG_UA_MICROCODE_CHANGED_WO_RESET,
                     dp->uas_bm);
         break;
     default:
         /* do nothing for this command for other mode values */
         break;
     }
     return 0;
 }
 
 static int resp_comp_write(struct scsi_cmnd *scp,
                struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     u8 *arr;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     u64 lba;
     u32 dnum;
     u32 lb_size = sdebug_sector_size;
     u8 num;
     int ret;
     int retval = 0;
 
     lba = get_unaligned_be64(cmd + 2);
     num = cmd[13];      /* 1 to a maximum of 255 logical blocks */
     if (0 == num)
         return 0;   /* degenerate case, not an error */
     if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
         (cmd[1] & 0xe0)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
     if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
          sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
         (cmd[1] & 0xe0) == 0)
         sdev_printk(KERN_ERR, scp->device, "Unprotected WR "
                 "to DIF device\n");
     ret = check_device_access_params(scp, lba, num, false);
     if (ret)
         return ret;
     dnum = 2 * num;
     arr = kcalloc(lb_size, dnum, GFP_ATOMIC);
     if (NULL == arr) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
                 INSUFF_RES_ASCQ);
         return check_condition_result;
     }
 
     sdeb_write_lock(sip);
 
     ret = do_dout_fetch(scp, dnum, arr);
     if (ret == -1) {
         retval = DID_ERROR << 16;
         goto cleanup;
     } else if (sdebug_verbose && (ret < (dnum * lb_size)))
         sdev_printk(KERN_INFO, scp->device, "%s: compare_write: cdb "
                 "indicated=%u, IO sent=%d bytes\n", my_name,
                 dnum * lb_size, ret);
     if (!comp_write_worker(sip, lba, num, arr, false)) {
         mk_sense_buffer(scp, MISCOMPARE, MISCOMPARE_VERIFY_ASC, 0);
         retval = check_condition_result;
         goto cleanup;
     }
     if (scsi_debug_lbp())
         map_region(sip, lba, num);
 cleanup:
     sdeb_write_unlock(sip);
     kfree(arr);
     return retval;
 }
 
 struct unmap_block_desc {
     __be64  lba;
     __be32  blocks;
     __be32  __reserved;
 };
 
 static int resp_unmap(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     unsigned char *buf;
     struct unmap_block_desc *desc;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     unsigned int i, payload_len, descriptors;
     int ret;
 
     if (!scsi_debug_lbp())
         return 0;   /* fib and say its done */
     payload_len = get_unaligned_be16(scp->cmnd + 7);
     BUG_ON(scsi_bufflen(scp) != payload_len);
 
     descriptors = (payload_len - 8) / 16;
     if (descriptors > sdebug_unmap_max_desc) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 7, -1);
         return check_condition_result;
     }
 
     buf = kzalloc(scsi_bufflen(scp), GFP_ATOMIC);
     if (!buf) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
                 INSUFF_RES_ASCQ);
         return check_condition_result;
     }
 
     scsi_sg_copy_to_buffer(scp, buf, scsi_bufflen(scp));
 
     BUG_ON(get_unaligned_be16(&buf[0]) != payload_len - 2);
     BUG_ON(get_unaligned_be16(&buf[2]) != descriptors * 16);
 
     desc = (void *)&buf[8];
 
     sdeb_write_lock(sip);
 
     for (i = 0 ; i < descriptors ; i++) {
         unsigned long long lba = get_unaligned_be64(&desc[i].lba);
         unsigned int num = get_unaligned_be32(&desc[i].blocks);
 
         ret = check_device_access_params(scp, lba, num, true);
         if (ret)
             goto out;
 
         unmap_region(sip, lba, num);
     }
 
     ret = 0;
 
 out:
     sdeb_write_unlock(sip);
     kfree(buf);
 
     return ret;
 }
 
 #define SDEBUG_GET_LBA_STATUS_LEN 32
 
 static int resp_get_lba_status(struct scsi_cmnd *scp,
                    struct sdebug_dev_info *devip)
 {
     u8 *cmd = scp->cmnd;
     u64 lba;
     u32 alloc_len, mapped, num;
     int ret;
     u8 arr[SDEBUG_GET_LBA_STATUS_LEN];
 
     lba = get_unaligned_be64(cmd + 2);
     alloc_len = get_unaligned_be32(cmd + 10);
 
     if (alloc_len < 24)
         return 0;
 
     ret = check_device_access_params(scp, lba, 1, false);
     if (ret)
         return ret;
 
     if (scsi_debug_lbp()) {
         struct sdeb_store_info *sip = devip2sip(devip, true);
 
         mapped = map_state(sip, lba, &num);
     } else {
         mapped = 1;
         /* following just in case virtual_gb changed */
         sdebug_capacity = get_sdebug_capacity();
         if (sdebug_capacity - lba <= 0xffffffff)
             num = sdebug_capacity - lba;
         else
             num = 0xffffffff;
     }
 
     memset(arr, 0, SDEBUG_GET_LBA_STATUS_LEN);
     put_unaligned_be32(20, arr);        /* Parameter Data Length */
     put_unaligned_be64(lba, arr + 8);   /* LBA */
     put_unaligned_be32(num, arr + 16);  /* Number of blocks */
     arr[20] = !mapped;      /* prov_stat=0: mapped; 1: dealloc */
 
     return fill_from_dev_buffer(scp, arr, SDEBUG_GET_LBA_STATUS_LEN);
 }
 
 static int resp_sync_cache(struct scsi_cmnd *scp,
                struct sdebug_dev_info *devip)
 {
     int res = 0;
     u64 lba;
     u32 num_blocks;
     u8 *cmd = scp->cmnd;
 
     if (cmd[0] == SYNCHRONIZE_CACHE) {  /* 10 byte cdb */
         lba = get_unaligned_be32(cmd + 2);
         num_blocks = get_unaligned_be16(cmd + 7);
     } else {                /* SYNCHRONIZE_CACHE(16) */
         lba = get_unaligned_be64(cmd + 2);
         num_blocks = get_unaligned_be32(cmd + 10);
     }
     if (lba + num_blocks > sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         return check_condition_result;
     }
     if (!write_since_sync || (cmd[1] & 0x2))
         res = SDEG_RES_IMMED_MASK;
     else        /* delay if write_since_sync and IMMED clear */
         write_since_sync = false;
     return res;
 }
 
 /*
  * Assuming the LBA+num_blocks is not out-of-range, this function will return
  * CONDITION MET if the specified blocks will/have fitted in the cache, and
  * a GOOD status otherwise. Model a disk with a big cache and yield
  * CONDITION MET. Actually tries to bring range in main memory into the
  * cache associated with the CPU(s).
  */
 static int resp_pre_fetch(struct scsi_cmnd *scp,
               struct sdebug_dev_info *devip)
 {
     int res = 0;
     u64 lba;
     u64 block, rest = 0;
     u32 nblks;
     u8 *cmd = scp->cmnd;
     struct sdeb_store_info *sip = devip2sip(devip, true);
     u8 *fsp = sip->storep;
 
     if (cmd[0] == PRE_FETCH) {  /* 10 byte cdb */
         lba = get_unaligned_be32(cmd + 2);
         nblks = get_unaligned_be16(cmd + 7);
     } else {            /* PRE-FETCH(16) */
         lba = get_unaligned_be64(cmd + 2);
         nblks = get_unaligned_be32(cmd + 10);
     }
     if (lba + nblks > sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         return check_condition_result;
     }
     if (!fsp)
         goto fini;
     /* PRE-FETCH spec says nothing about LBP or PI so skip them */
     block = do_div(lba, sdebug_store_sectors);
     if (block + nblks > sdebug_store_sectors)
         rest = block + nblks - sdebug_store_sectors;
 
     /* Try to bring the PRE-FETCH range into CPU's cache */
     sdeb_read_lock(sip);
     prefetch_range(fsp + (sdebug_sector_size * block),
                (nblks - rest) * sdebug_sector_size);
     if (rest)
         prefetch_range(fsp, rest * sdebug_sector_size);
     sdeb_read_unlock(sip);
 fini:
     if (cmd[1] & 0x2)
         res = SDEG_RES_IMMED_MASK;
     return res | condition_met_result;
 }
 
 #define RL_BUCKET_ELEMS 8
 
 /* Even though each pseudo target has a REPORT LUNS "well known logical unit"
  * (W-LUN), the normal Linux scanning logic does not associate it with a
  * device (e.g. /dev/sg7). The following magic will make that association:
  *   "cd /sys/class/scsi_host/host<n> ; echo '- - 49409' > scan"
  * where <n> is a host number. If there are multiple targets in a host then
  * the above will associate a W-LUN to each target. To only get a W-LUN
  * for target 2, then use "echo '- 2 49409' > scan" .
  */
 static int resp_report_luns(struct scsi_cmnd *scp,
                 struct sdebug_dev_info *devip)
 {
     unsigned char *cmd = scp->cmnd;
     unsigned int alloc_len;
     unsigned char select_report;
     u64 lun;
     struct scsi_lun *lun_p;
     u8 arr[RL_BUCKET_ELEMS * sizeof(struct scsi_lun)];
     unsigned int lun_cnt;   /* normal LUN count (max: 256) */
     unsigned int wlun_cnt;  /* report luns W-LUN count */
     unsigned int tlun_cnt;  /* total LUN count */
     unsigned int rlen;  /* response length (in bytes) */
     int k, j, n, res;
     unsigned int off_rsp = 0;
     const int sz_lun = sizeof(struct scsi_lun);
 
     clear_luns_changed_on_target(devip);
 
     select_report = cmd[2];
     alloc_len = get_unaligned_be32(cmd + 6);
 
     if (alloc_len < 4) {
         pr_err("alloc len too small %d\n", alloc_len);
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
         return check_condition_result;
     }
 
     switch (select_report) {
     case 0:     /* all LUNs apart from W-LUNs */
         lun_cnt = sdebug_max_luns;
         wlun_cnt = 0;
         break;
     case 1:     /* only W-LUNs */
         lun_cnt = 0;
         wlun_cnt = 1;
         break;
     case 2:     /* all LUNs */
         lun_cnt = sdebug_max_luns;
         wlun_cnt = 1;
         break;
     case 0x10:  /* only administrative LUs */
     case 0x11:  /* see SPC-5 */
     case 0x12:  /* only subsiduary LUs owned by referenced LU */
     default:
         pr_debug("select report invalid %d\n", select_report);
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, -1);
         return check_condition_result;
     }
 
     if (sdebug_no_lun_0 && (lun_cnt > 0))
         --lun_cnt;
 
     tlun_cnt = lun_cnt + wlun_cnt;
     rlen = tlun_cnt * sz_lun;   /* excluding 8 byte header */
     scsi_set_resid(scp, scsi_bufflen(scp));
     pr_debug("select_report %d luns = %d wluns = %d no_lun0 %d\n",
          select_report, lun_cnt, wlun_cnt, sdebug_no_lun_0);
 
     /* loops rely on sizeof response header same as sizeof lun (both 8) */
     lun = sdebug_no_lun_0 ? 1 : 0;
     for (k = 0, j = 0, res = 0; true; ++k, j = 0) {
         memset(arr, 0, sizeof(arr));
         lun_p = (struct scsi_lun *)&arr[0];
         if (k == 0) {
             put_unaligned_be32(rlen, &arr[0]);
             ++lun_p;
             j = 1;
         }
         for ( ; j < RL_BUCKET_ELEMS; ++j, ++lun_p) {
             if ((k * RL_BUCKET_ELEMS) + j > lun_cnt)
                 break;
             int_to_scsilun(lun++, lun_p);
             if (lun > 1 && sdebug_lun_am == SAM_LUN_AM_FLAT)
                 lun_p->scsi_lun[0] |= 0x40;
         }
         if (j < RL_BUCKET_ELEMS)
             break;
         n = j * sz_lun;
         res = p_fill_from_dev_buffer(scp, arr, n, off_rsp);
         if (res)
             return res;
         off_rsp += n;
     }
     if (wlun_cnt) {
         int_to_scsilun(SCSI_W_LUN_REPORT_LUNS, lun_p);
         ++j;
     }
     if (j > 0)
         res = p_fill_from_dev_buffer(scp, arr, j * sz_lun, off_rsp);
     return res;
 }
 
 static int resp_verify(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     bool is_bytchk3 = false;
     u8 bytchk;
     int ret, j;
     u32 vnum, a_num, off;
     const u32 lb_size = sdebug_sector_size;
     u64 lba;
     u8 *arr;
     u8 *cmd = scp->cmnd;
     struct sdeb_store_info *sip = devip2sip(devip, true);
 
     bytchk = (cmd[1] >> 1) & 0x3;
     if (bytchk == 0) {
         return 0;   /* always claim internal verify okay */
     } else if (bytchk == 2) {
         mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 2);
         return check_condition_result;
     } else if (bytchk == 3) {
         is_bytchk3 = true;  /* 1 block sent, compared repeatedly */
     }
     switch (cmd[0]) {
     case VERIFY_16:
         lba = get_unaligned_be64(cmd + 2);
         vnum = get_unaligned_be32(cmd + 10);
         break;
     case VERIFY:        /* is VERIFY(10) */
         lba = get_unaligned_be32(cmd + 2);
         vnum = get_unaligned_be16(cmd + 7);
         break;
     default:
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
     if (vnum == 0)
         return 0;   /* not an error */
     a_num = is_bytchk3 ? 1 : vnum;
     /* Treat following check like one for read (i.e. no write) access */
     ret = check_device_access_params(scp, lba, a_num, false);
     if (ret)
         return ret;
 
     arr = kcalloc(lb_size, vnum, GFP_ATOMIC);
     if (!arr) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
                 INSUFF_RES_ASCQ);
         return check_condition_result;
     }
     /* Not changing store, so only need read access */
     sdeb_read_lock(sip);
 
     ret = do_dout_fetch(scp, a_num, arr);
     if (ret == -1) {
         ret = DID_ERROR << 16;
         goto cleanup;
     } else if (sdebug_verbose && (ret < (a_num * lb_size))) {
         sdev_printk(KERN_INFO, scp->device,
                 "%s: %s: cdb indicated=%u, IO sent=%d bytes\n",
                 my_name, __func__, a_num * lb_size, ret);
     }
     if (is_bytchk3) {
         for (j = 1, off = lb_size; j < vnum; ++j, off += lb_size)
             memcpy(arr + off, arr, lb_size);
     }
     ret = 0;
     if (!comp_write_worker(sip, lba, vnum, arr, true)) {
         mk_sense_buffer(scp, MISCOMPARE, MISCOMPARE_VERIFY_ASC, 0);
         ret = check_condition_result;
         goto cleanup;
     }
 cleanup:
     sdeb_read_unlock(sip);
     kfree(arr);
     return ret;
 }
 
 #define RZONES_DESC_HD 64
 
 /* Report zones depending on start LBA and reporting options */
 static int resp_report_zones(struct scsi_cmnd *scp,
                  struct sdebug_dev_info *devip)
 {
     unsigned int rep_max_zones, nrz = 0;
     int ret = 0;
     u32 alloc_len, rep_opts, rep_len;
     bool partial;
     u64 lba, zs_lba;
     u8 *arr = NULL, *desc;
     u8 *cmd = scp->cmnd;
     struct sdeb_zone_state *zsp = NULL;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!sdebug_dev_is_zoned(devip)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
     zs_lba = get_unaligned_be64(cmd + 2);
     alloc_len = get_unaligned_be32(cmd + 10);
     if (alloc_len == 0)
         return 0;   /* not an error */
     rep_opts = cmd[14] & 0x3f;
     partial = cmd[14] & 0x80;
 
     if (zs_lba >= sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         return check_condition_result;
     }
 
     rep_max_zones = (alloc_len - 64) >> ilog2(RZONES_DESC_HD);
 
     arr = kzalloc(alloc_len, GFP_ATOMIC);
     if (!arr) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
                 INSUFF_RES_ASCQ);
         return check_condition_result;
     }
 
     sdeb_read_lock(sip);
 
     desc = arr + 64;
     for (lba = zs_lba; lba < sdebug_capacity;
          lba = zsp->z_start + zsp->z_size) {
         if (WARN_ONCE(zbc_zone(devip, lba) == zsp, "lba = %llu\n", lba))
             break;
         zsp = zbc_zone(devip, lba);
         switch (rep_opts) {
         case 0x00:
             /* All zones */
             break;
         case 0x01:
             /* Empty zones */
             if (zsp->z_cond != ZC1_EMPTY)
                 continue;
             break;
         case 0x02:
             /* Implicit open zones */
             if (zsp->z_cond != ZC2_IMPLICIT_OPEN)
                 continue;
             break;
         case 0x03:
             /* Explicit open zones */
             if (zsp->z_cond != ZC3_EXPLICIT_OPEN)
                 continue;
             break;
         case 0x04:
             /* Closed zones */
             if (zsp->z_cond != ZC4_CLOSED)
                 continue;
             break;
         case 0x05:
             /* Full zones */
             if (zsp->z_cond != ZC5_FULL)
                 continue;
             break;
         case 0x06:
         case 0x07:
         case 0x10:
             /*
              * Read-only, offline, reset WP recommended are
              * not emulated: no zones to report;
              */
             continue;
         case 0x11:
             /* non-seq-resource set */
             if (!zsp->z_non_seq_resource)
                 continue;
             break;
         case 0x3e:
             /* All zones except gap zones. */
             if (zbc_zone_is_gap(zsp))
                 continue;
             break;
         case 0x3f:
             /* Not write pointer (conventional) zones */
             if (zbc_zone_is_seq(zsp))
                 continue;
             break;
         default:
             mk_sense_buffer(scp, ILLEGAL_REQUEST,
                     INVALID_FIELD_IN_CDB, 0);
             ret = check_condition_result;
             goto fini;
         }
 
         if (nrz < rep_max_zones) {
             /* Fill zone descriptor */
             desc[0] = zsp->z_type;
             desc[1] = zsp->z_cond << 4;
             if (zsp->z_non_seq_resource)
                 desc[1] |= 1 << 1;
             put_unaligned_be64((u64)zsp->z_size, desc + 8);
             put_unaligned_be64((u64)zsp->z_start, desc + 16);
             put_unaligned_be64((u64)zsp->z_wp, desc + 24);
             desc += 64;
         }
 
         if (partial && nrz >= rep_max_zones)
             break;
 
         nrz++;
     }
 
     /* Report header */
     /* Zone list length. */
     put_unaligned_be32(nrz * RZONES_DESC_HD, arr + 0);
     /* Maximum LBA */
     put_unaligned_be64(sdebug_capacity - 1, arr + 8);
     /* Zone starting LBA granularity. */
     if (devip->zcap < devip->zsize)
         put_unaligned_be64(devip->zsize, arr + 16);
 
     rep_len = (unsigned long)desc - (unsigned long)arr;
     ret = fill_from_dev_buffer(scp, arr, min_t(u32, alloc_len, rep_len));
 
 fini:
     sdeb_read_unlock(sip);
     kfree(arr);
     return ret;
 }
 
 /* Logic transplanted from tcmu-runner, file_zbc.c */
 static void zbc_open_all(struct sdebug_dev_info *devip)
 {
     struct sdeb_zone_state *zsp = &devip->zstate[0];
     unsigned int i;
 
     for (i = 0; i < devip->nr_zones; i++, zsp++) {
         if (zsp->z_cond == ZC4_CLOSED)
             zbc_open_zone(devip, &devip->zstate[i], true);
     }
 }
 
 static int resp_open_zone(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     int res = 0;
     u64 z_id;
     enum sdebug_z_cond zc;
     u8 *cmd = scp->cmnd;
     struct sdeb_zone_state *zsp;
     bool all = cmd[14] & 0x01;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!sdebug_dev_is_zoned(devip)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
 
     sdeb_write_lock(sip);
 
     if (all) {
         /* Check if all closed zones can be open */
         if (devip->max_open &&
             devip->nr_exp_open + devip->nr_closed > devip->max_open) {
             mk_sense_buffer(scp, DATA_PROTECT, INSUFF_RES_ASC,
                     INSUFF_ZONE_ASCQ);
             res = check_condition_result;
             goto fini;
         }
         /* Open all closed zones */
         zbc_open_all(devip);
         goto fini;
     }
 
     /* Open the specified zone */
     z_id = get_unaligned_be64(cmd + 2);
     if (z_id >= sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zsp = zbc_zone(devip, z_id);
     if (z_id != zsp->z_start) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
     if (zbc_zone_is_conv(zsp)) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zc = zsp->z_cond;
     if (zc == ZC3_EXPLICIT_OPEN || zc == ZC5_FULL)
         goto fini;
 
     if (devip->max_open && devip->nr_exp_open >= devip->max_open) {
         mk_sense_buffer(scp, DATA_PROTECT, INSUFF_RES_ASC,
                 INSUFF_ZONE_ASCQ);
         res = check_condition_result;
         goto fini;
     }
 
     zbc_open_zone(devip, zsp, true);
 fini:
     sdeb_write_unlock(sip);
     return res;
 }
 
 static void zbc_close_all(struct sdebug_dev_info *devip)
 {
     unsigned int i;
 
     for (i = 0; i < devip->nr_zones; i++)
         zbc_close_zone(devip, &devip->zstate[i]);
 }
 
 static int resp_close_zone(struct scsi_cmnd *scp,
                struct sdebug_dev_info *devip)
 {
     int res = 0;
     u64 z_id;
     u8 *cmd = scp->cmnd;
     struct sdeb_zone_state *zsp;
     bool all = cmd[14] & 0x01;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!sdebug_dev_is_zoned(devip)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
 
     sdeb_write_lock(sip);
 
     if (all) {
         zbc_close_all(devip);
         goto fini;
     }
 
     /* Close specified zone */
     z_id = get_unaligned_be64(cmd + 2);
     if (z_id >= sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zsp = zbc_zone(devip, z_id);
     if (z_id != zsp->z_start) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
     if (zbc_zone_is_conv(zsp)) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zbc_close_zone(devip, zsp);
 fini:
     sdeb_write_unlock(sip);
     return res;
 }
 
 static void zbc_finish_zone(struct sdebug_dev_info *devip,
                 struct sdeb_zone_state *zsp, bool empty)
 {
     enum sdebug_z_cond zc = zsp->z_cond;
 
     if (zc == ZC4_CLOSED || zc == ZC2_IMPLICIT_OPEN ||
         zc == ZC3_EXPLICIT_OPEN || (empty && zc == ZC1_EMPTY)) {
         if (zc == ZC2_IMPLICIT_OPEN || zc == ZC3_EXPLICIT_OPEN)
             zbc_close_zone(devip, zsp);
         if (zsp->z_cond == ZC4_CLOSED)
             devip->nr_closed--;
         zsp->z_wp = zsp->z_start + zsp->z_size;
         zsp->z_cond = ZC5_FULL;
     }
 }
 
 static void zbc_finish_all(struct sdebug_dev_info *devip)
 {
     unsigned int i;
 
     for (i = 0; i < devip->nr_zones; i++)
         zbc_finish_zone(devip, &devip->zstate[i], false);
 }
 
 static int resp_finish_zone(struct scsi_cmnd *scp,
                 struct sdebug_dev_info *devip)
 {
     struct sdeb_zone_state *zsp;
     int res = 0;
     u64 z_id;
     u8 *cmd = scp->cmnd;
     bool all = cmd[14] & 0x01;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!sdebug_dev_is_zoned(devip)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
 
     sdeb_write_lock(sip);
 
     if (all) {
         zbc_finish_all(devip);
         goto fini;
     }
 
     /* Finish the specified zone */
     z_id = get_unaligned_be64(cmd + 2);
     if (z_id >= sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zsp = zbc_zone(devip, z_id);
     if (z_id != zsp->z_start) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
     if (zbc_zone_is_conv(zsp)) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zbc_finish_zone(devip, zsp, true);
 fini:
     sdeb_write_unlock(sip);
     return res;
 }
 
 static void zbc_rwp_zone(struct sdebug_dev_info *devip,
              struct sdeb_zone_state *zsp)
 {
     enum sdebug_z_cond zc;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!zbc_zone_is_seq(zsp))
         return;
 
     zc = zsp->z_cond;
     if (zc == ZC2_IMPLICIT_OPEN || zc == ZC3_EXPLICIT_OPEN)
         zbc_close_zone(devip, zsp);
 
     if (zsp->z_cond == ZC4_CLOSED)
         devip->nr_closed--;
 
     if (zsp->z_wp > zsp->z_start)
         memset(sip->storep + zsp->z_start * sdebug_sector_size, 0,
                (zsp->z_wp - zsp->z_start) * sdebug_sector_size);
 
     zsp->z_non_seq_resource = false;
     zsp->z_wp = zsp->z_start;
     zsp->z_cond = ZC1_EMPTY;
 }
 
 static void zbc_rwp_all(struct sdebug_dev_info *devip)
 {
     unsigned int i;
 
     for (i = 0; i < devip->nr_zones; i++)
         zbc_rwp_zone(devip, &devip->zstate[i]);
 }
 
 static int resp_rwp_zone(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     struct sdeb_zone_state *zsp;
     int res = 0;
     u64 z_id;
     u8 *cmd = scp->cmnd;
     bool all = cmd[14] & 0x01;
     struct sdeb_store_info *sip = devip2sip(devip, false);
 
     if (!sdebug_dev_is_zoned(devip)) {
         mk_sense_invalid_opcode(scp);
         return check_condition_result;
     }
 
     sdeb_write_lock(sip);
 
     if (all) {
         zbc_rwp_all(devip);
         goto fini;
     }
 
     z_id = get_unaligned_be64(cmd + 2);
     if (z_id >= sdebug_capacity) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zsp = zbc_zone(devip, z_id);
     if (z_id != zsp->z_start) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
     if (zbc_zone_is_conv(zsp)) {
         mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
         res = check_condition_result;
         goto fini;
     }
 
     zbc_rwp_zone(devip, zsp);
 fini:
     sdeb_write_unlock(sip);
     return res;
 }
 
 static struct sdebug_queue *get_queue(struct scsi_cmnd *cmnd)
 {
     u16 hwq;
     u32 tag = blk_mq_unique_tag(scsi_cmd_to_rq(cmnd));
 
     hwq = blk_mq_unique_tag_to_hwq(tag);
 
     pr_debug("tag=%#x, hwq=%d\n", tag, hwq);
     if (WARN_ON_ONCE(hwq >= submit_queues))
         hwq = 0;
 
     return sdebug_q_arr + hwq;
 }
 
 static u32 get_tag(struct scsi_cmnd *cmnd)
 {
     return blk_mq_unique_tag(scsi_cmd_to_rq(cmnd));
 }
 
 /* Queued (deferred) command completions converge here. */
 static void sdebug_q_cmd_complete(struct sdebug_defer *sd_dp)
 {
     bool aborted = sd_dp->aborted;
     int qc_idx;
     int retiring = 0;
     unsigned long iflags;
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
     struct scsi_cmnd *scp;
     struct sdebug_dev_info *devip;
 
     if (unlikely(aborted))
         sd_dp->aborted = false;
     qc_idx = sd_dp->qc_idx;
     sqp = sdebug_q_arr + sd_dp->sqa_idx;
     if (sdebug_statistics) {
         atomic_inc(&sdebug_completions);
         if (raw_smp_processor_id() != sd_dp->issuing_cpu)
             atomic_inc(&sdebug_miss_cpus);
     }
     if (unlikely((qc_idx < 0) || (qc_idx >= SDEBUG_CANQUEUE))) {
         pr_err("wild qc_idx=%d\n", qc_idx);
         return;
     }
     spin_lock_irqsave(&sqp->qc_lock, iflags);
     WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_NONE);
     sqcp = &sqp->qc_arr[qc_idx];
     scp = sqcp->a_cmnd;
     if (unlikely(scp == NULL)) {
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         pr_err("scp is NULL, sqa_idx=%d, qc_idx=%d, hc_idx=%d\n",
                sd_dp->sqa_idx, qc_idx, sd_dp->hc_idx);
         return;
     }
     devip = (struct sdebug_dev_info *)scp->device->hostdata;
     if (likely(devip))
         atomic_dec(&devip->num_in_q);
     else
         pr_err("devip=NULL\n");
     if (unlikely(atomic_read(&retired_max_queue) > 0))
         retiring = 1;
 
     sqcp->a_cmnd = NULL;
     if (unlikely(!test_and_clear_bit(qc_idx, sqp->in_use_bm))) {
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         pr_err("Unexpected completion\n");
         return;
     }
 
     if (unlikely(retiring)) {   /* user has reduced max_queue */
         int k, retval;
 
         retval = atomic_read(&retired_max_queue);
         if (qc_idx >= retval) {
             spin_unlock_irqrestore(&sqp->qc_lock, iflags);
             pr_err("index %d too large\n", retval);
             return;
         }
         k = find_last_bit(sqp->in_use_bm, retval);
         if ((k < sdebug_max_queue) || (k == retval))
             atomic_set(&retired_max_queue, 0);
         else
             atomic_set(&retired_max_queue, k + 1);
     }
     spin_unlock_irqrestore(&sqp->qc_lock, iflags);
     if (unlikely(aborted)) {
         if (sdebug_verbose)
             pr_info("bypassing scsi_done() due to aborted cmd\n");
         return;
     }
     scsi_done(scp); /* callback to mid level */
 }
 
 /* When high resolution timer goes off this function is called. */
 static enum hrtimer_restart sdebug_q_cmd_hrt_complete(struct hrtimer *timer)
 {
     struct sdebug_defer *sd_dp = container_of(timer, struct sdebug_defer,
                           hrt);
     sdebug_q_cmd_complete(sd_dp);
     return HRTIMER_NORESTART;
 }
 
 /* When work queue schedules work, it calls this function. */
 static void sdebug_q_cmd_wq_complete(struct work_struct *work)
 {
     struct sdebug_defer *sd_dp = container_of(work, struct sdebug_defer,
                           ew.work);
     sdebug_q_cmd_complete(sd_dp);
 }
 
 static bool got_shared_uuid;
 static uuid_t shared_uuid;
 
 static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 {
     struct sdeb_zone_state *zsp;
     sector_t capacity = get_sdebug_capacity();
     sector_t conv_capacity;
     sector_t zstart = 0;
     unsigned int i;
 
     /*
      * Set the zone size: if sdeb_zbc_zone_size_mb is not set, figure out
      * a zone size allowing for at least 4 zones on the device. Otherwise,
      * use the specified zone size checking that at least 2 zones can be
      * created for the device.
      */
     if (!sdeb_zbc_zone_size_mb) {
         devip->zsize = (DEF_ZBC_ZONE_SIZE_MB * SZ_1M)
             >> ilog2(sdebug_sector_size);
         while (capacity < devip->zsize << 2 && devip->zsize >= 2)
             devip->zsize >>= 1;
         if (devip->zsize < 2) {
             pr_err("Device capacity too small\n");
             return -EINVAL;
         }
     } else {
         if (!is_power_of_2(sdeb_zbc_zone_size_mb)) {
             pr_err("Zone size is not a power of 2\n");
             return -EINVAL;
         }
         devip->zsize = (sdeb_zbc_zone_size_mb * SZ_1M)
             >> ilog2(sdebug_sector_size);
         if (devip->zsize >= capacity) {
             pr_err("Zone size too large for device capacity\n");
             return -EINVAL;
         }
     }
 
     devip->zsize_shift = ilog2(devip->zsize);
     devip->nr_zones = (capacity + devip->zsize - 1) >> devip->zsize_shift;
 
     if (sdeb_zbc_zone_cap_mb == 0) {
         devip->zcap = devip->zsize;
     } else {
         devip->zcap = (sdeb_zbc_zone_cap_mb * SZ_1M) >>
                   ilog2(sdebug_sector_size);
         if (devip->zcap > devip->zsize) {
             pr_err("Zone capacity too large\n");
             return -EINVAL;
         }
     }
 
     conv_capacity = (sector_t)sdeb_zbc_nr_conv << devip->zsize_shift;
     if (conv_capacity >= capacity) {
         pr_err("Number of conventional zones too large\n");
         return -EINVAL;
     }
     devip->nr_conv_zones = sdeb_zbc_nr_conv;
     devip->nr_seq_zones = ALIGN(capacity - conv_capacity, devip->zsize) >>
                   devip->zsize_shift;
     devip->nr_zones = devip->nr_conv_zones + devip->nr_seq_zones;
 
     /* Add gap zones if zone capacity is smaller than the zone size */
     if (devip->zcap < devip->zsize)
         devip->nr_zones += devip->nr_seq_zones;
 
     if (devip->zmodel == BLK_ZONED_HM) {
         /* zbc_max_open_zones can be 0, meaning "not reported" */
         if (sdeb_zbc_max_open >= devip->nr_zones - 1)
             devip->max_open = (devip->nr_zones - 1) / 2;
         else
             devip->max_open = sdeb_zbc_max_open;
     }
 
     devip->zstate = kcalloc(devip->nr_zones,
                 sizeof(struct sdeb_zone_state), GFP_KERNEL);
     if (!devip->zstate)
         return -ENOMEM;
 
     for (i = 0; i < devip->nr_zones; i++) {
         zsp = &devip->zstate[i];
 
         zsp->z_start = zstart;
 
         if (i < devip->nr_conv_zones) {
             zsp->z_type = ZBC_ZTYPE_CNV;
             zsp->z_cond = ZBC_NOT_WRITE_POINTER;
             zsp->z_wp = (sector_t)-1;
             zsp->z_size =
                 min_t(u64, devip->zsize, capacity - zstart);
         } else if ((zstart & (devip->zsize - 1)) == 0) {
             if (devip->zmodel == BLK_ZONED_HM)
                 zsp->z_type = ZBC_ZTYPE_SWR;
             else
                 zsp->z_type = ZBC_ZTYPE_SWP;
             zsp->z_cond = ZC1_EMPTY;
             zsp->z_wp = zsp->z_start;
             zsp->z_size =
                 min_t(u64, devip->zcap, capacity - zstart);
         } else {
             zsp->z_type = ZBC_ZTYPE_GAP;
             zsp->z_cond = ZBC_NOT_WRITE_POINTER;
             zsp->z_wp = (sector_t)-1;
             zsp->z_size = min_t(u64, devip->zsize - devip->zcap,
                         capacity - zstart);
         }
 
         WARN_ON_ONCE((int)zsp->z_size <= 0);
         zstart += zsp->z_size;
     }
 
     return 0;
 }
 
 static struct sdebug_dev_info *sdebug_device_create(
             struct sdebug_host_info *sdbg_host, gfp_t flags)
 {
     struct sdebug_dev_info *devip;
 
     devip = kzalloc(sizeof(*devip), flags);
     if (devip) {
         if (sdebug_uuid_ctl == 1)
             uuid_gen(&devip->lu_name);
         else if (sdebug_uuid_ctl == 2) {
             if (got_shared_uuid)
                 devip->lu_name = shared_uuid;
             else {
                 uuid_gen(&shared_uuid);
                 got_shared_uuid = true;
                 devip->lu_name = shared_uuid;
             }
         }
         devip->sdbg_host = sdbg_host;
         if (sdeb_zbc_in_use) {
             devip->zmodel = sdeb_zbc_model;
             if (sdebug_device_create_zones(devip)) {
                 kfree(devip);
                 return NULL;
             }
         } else {
             devip->zmodel = BLK_ZONED_NONE;
         }
         devip->sdbg_host = sdbg_host;
         devip->create_ts = ktime_get_boottime();
         atomic_set(&devip->stopped, (sdeb_tur_ms_to_ready > 0 ? 2 : 0));
         list_add_tail(&devip->dev_list, &sdbg_host->dev_info_list);
     }
     return devip;
 }
 
 static struct sdebug_dev_info *find_build_dev_info(struct scsi_device *sdev)
 {
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *open_devip = NULL;
     struct sdebug_dev_info *devip;
 
     sdbg_host = *(struct sdebug_host_info **)shost_priv(sdev->host);
     if (!sdbg_host) {
         pr_err("Host info NULL\n");
         return NULL;
     }
 
     list_for_each_entry(devip, &sdbg_host->dev_info_list, dev_list) {
         if ((devip->used) && (devip->channel == sdev->channel) &&
             (devip->target == sdev->id) &&
             (devip->lun == sdev->lun))
             return devip;
         else {
             if ((!devip->used) && (!open_devip))
                 open_devip = devip;
         }
     }
     if (!open_devip) { /* try and make a new one */
         open_devip = sdebug_device_create(sdbg_host, GFP_ATOMIC);
         if (!open_devip) {
             pr_err("out of memory at line %d\n", __LINE__);
             return NULL;
         }
     }
 
     open_devip->channel = sdev->channel;
     open_devip->target = sdev->id;
     open_devip->lun = sdev->lun;
     open_devip->sdbg_host = sdbg_host;
     atomic_set(&open_devip->num_in_q, 0);
     set_bit(SDEBUG_UA_POOCCUR, open_devip->uas_bm);
     open_devip->used = true;
     return open_devip;
 }
 
 static int scsi_debug_slave_alloc(struct scsi_device *sdp)
 {
     if (sdebug_verbose)
         pr_info("slave_alloc <%u %u %u %llu>\n",
                sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
     return 0;
 }
 
 static int scsi_debug_slave_configure(struct scsi_device *sdp)
 {
     struct sdebug_dev_info *devip =
             (struct sdebug_dev_info *)sdp->hostdata;
 
     if (sdebug_verbose)
         pr_info("slave_configure <%u %u %u %llu>\n",
                sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
     if (sdp->host->max_cmd_len != SDEBUG_MAX_CMD_LEN)
         sdp->host->max_cmd_len = SDEBUG_MAX_CMD_LEN;
     if (devip == NULL) {
         devip = find_build_dev_info(sdp);
         if (devip == NULL)
             return 1;  /* no resources, will be marked offline */
     }
     sdp->hostdata = devip;
     if (sdebug_no_uld)
         sdp->no_uld_attach = 1;
     config_cdb_len(sdp);
     return 0;
 }
 
 static void scsi_debug_slave_destroy(struct scsi_device *sdp)
 {
     struct sdebug_dev_info *devip =
         (struct sdebug_dev_info *)sdp->hostdata;
 
     if (sdebug_verbose)
         pr_info("slave_destroy <%u %u %u %llu>\n",
                sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
     if (devip) {
         /* make this slot available for re-use */
         devip->used = false;
         sdp->hostdata = NULL;
     }
 }
 
 static void stop_qc_helper(struct sdebug_defer *sd_dp,
                enum sdeb_defer_type defer_t)
 {
     if (!sd_dp)
         return;
     if (defer_t == SDEB_DEFER_HRT)
         hrtimer_cancel(&sd_dp->hrt);
     else if (defer_t == SDEB_DEFER_WQ)
         cancel_work_sync(&sd_dp->ew.work);
 }
 
 /* If @cmnd found deletes its timer or work queue and returns true; else
    returns false */
 static bool stop_queued_cmnd(struct scsi_cmnd *cmnd)
 {
     unsigned long iflags;
     int j, k, qmax, r_qmax;
     enum sdeb_defer_type l_defer_t;
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
     struct sdebug_dev_info *devip;
     struct sdebug_defer *sd_dp;
 
     for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
         spin_lock_irqsave(&sqp->qc_lock, iflags);
         qmax = sdebug_max_queue;
         r_qmax = atomic_read(&retired_max_queue);
         if (r_qmax > qmax)
             qmax = r_qmax;
         for (k = 0; k < qmax; ++k) {
             if (test_bit(k, sqp->in_use_bm)) {
                 sqcp = &sqp->qc_arr[k];
                 if (cmnd != sqcp->a_cmnd)
                     continue;
                 /* found */
                 devip = (struct sdebug_dev_info *)
                         cmnd->device->hostdata;
                 if (devip)
                     atomic_dec(&devip->num_in_q);
                 sqcp->a_cmnd = NULL;
                 sd_dp = sqcp->sd_dp;
                 if (sd_dp) {
                     l_defer_t = READ_ONCE(sd_dp->defer_t);
                     WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_NONE);
                 } else
                     l_defer_t = SDEB_DEFER_NONE;
                 spin_unlock_irqrestore(&sqp->qc_lock, iflags);
                 stop_qc_helper(sd_dp, l_defer_t);
                 clear_bit(k, sqp->in_use_bm);
                 return true;
             }
         }
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
     }
     return false;
 }
 
 /* Deletes (stops) timers or work queues of all queued commands */
 static void stop_all_queued(void)
 {
     unsigned long iflags;
     int j, k;
     enum sdeb_defer_type l_defer_t;
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
     struct sdebug_dev_info *devip;
     struct sdebug_defer *sd_dp;
 
     for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
         spin_lock_irqsave(&sqp->qc_lock, iflags);
         for (k = 0; k < SDEBUG_CANQUEUE; ++k) {
             if (test_bit(k, sqp->in_use_bm)) {
                 sqcp = &sqp->qc_arr[k];
                 if (sqcp->a_cmnd == NULL)
                     continue;
                 devip = (struct sdebug_dev_info *)
                     sqcp->a_cmnd->device->hostdata;
                 if (devip)
                     atomic_dec(&devip->num_in_q);
                 sqcp->a_cmnd = NULL;
                 sd_dp = sqcp->sd_dp;
                 if (sd_dp) {
                     l_defer_t = READ_ONCE(sd_dp->defer_t);
                     WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_NONE);
                 } else
                     l_defer_t = SDEB_DEFER_NONE;
                 spin_unlock_irqrestore(&sqp->qc_lock, iflags);
                 stop_qc_helper(sd_dp, l_defer_t);
                 clear_bit(k, sqp->in_use_bm);
                 spin_lock_irqsave(&sqp->qc_lock, iflags);
             }
         }
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
     }
 }
 
 /* Free queued command memory on heap */
 static void free_all_queued(void)
 {
     int j, k;
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
 
     for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
         for (k = 0; k < SDEBUG_CANQUEUE; ++k) {
             sqcp = &sqp->qc_arr[k];
             kfree(sqcp->sd_dp);
             sqcp->sd_dp = NULL;
         }
     }
 }
 
 static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
 {
     bool ok;
 
     ++num_aborts;
     if (SCpnt) {
         ok = stop_queued_cmnd(SCpnt);
         if (SCpnt->device && (SDEBUG_OPT_ALL_NOISE & sdebug_opts))
             sdev_printk(KERN_INFO, SCpnt->device,
                     "%s: command%s found\n", __func__,
                     ok ? "" : " not");
     }
     return SUCCESS;
 }
 
 static int scsi_debug_device_reset(struct scsi_cmnd *SCpnt)
 {
     ++num_dev_resets;
     if (SCpnt && SCpnt->device) {
         struct scsi_device *sdp = SCpnt->device;
         struct sdebug_dev_info *devip =
                 (struct sdebug_dev_info *)sdp->hostdata;
 
         if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
             sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
         if (devip)
             set_bit(SDEBUG_UA_POR, devip->uas_bm);
     }
     return SUCCESS;
 }
 
 static int scsi_debug_target_reset(struct scsi_cmnd *SCpnt)
 {
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *devip;
     struct scsi_device *sdp;
     struct Scsi_Host *hp;
     int k = 0;
 
     ++num_target_resets;
     if (!SCpnt)
         goto lie;
     sdp = SCpnt->device;
     if (!sdp)
         goto lie;
     if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
         sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
     hp = sdp->host;
     if (!hp)
         goto lie;
     sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
     if (sdbg_host) {
         list_for_each_entry(devip,
                     &sdbg_host->dev_info_list,
                     dev_list)
             if (devip->target == sdp->id) {
                 set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
                 ++k;
             }
     }
     if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
         sdev_printk(KERN_INFO, sdp,
                 "%s: %d device(s) found in target\n", __func__, k);
 lie:
     return SUCCESS;
 }
 
 static int scsi_debug_bus_reset(struct scsi_cmnd *SCpnt)
 {
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *devip;
     struct scsi_device *sdp;
     struct Scsi_Host *hp;
     int k = 0;
 
     ++num_bus_resets;
     if (!(SCpnt && SCpnt->device))
         goto lie;
     sdp = SCpnt->device;
     if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
         sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
     hp = sdp->host;
     if (hp) {
         sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
         if (sdbg_host) {
             list_for_each_entry(devip,
                         &sdbg_host->dev_info_list,
                         dev_list) {
                 set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
                 ++k;
             }
         }
     }
     if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
         sdev_printk(KERN_INFO, sdp,
                 "%s: %d device(s) found in host\n", __func__, k);
 lie:
     return SUCCESS;
 }
 
 static int scsi_debug_host_reset(struct scsi_cmnd *SCpnt)
 {
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *devip;
     int k = 0;
 
     ++num_host_resets;
     if ((SCpnt->device) && (SDEBUG_OPT_ALL_NOISE & sdebug_opts))
         sdev_printk(KERN_INFO, SCpnt->device, "%s\n", __func__);
     spin_lock(&sdebug_host_list_lock);
     list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
         list_for_each_entry(devip, &sdbg_host->dev_info_list,
                     dev_list) {
             set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
             ++k;
         }
     }
     spin_unlock(&sdebug_host_list_lock);
     stop_all_queued();
     if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
         sdev_printk(KERN_INFO, SCpnt->device,
                 "%s: %d device(s) found\n", __func__, k);
     return SUCCESS;
 }
 
 static void sdebug_build_parts(unsigned char *ramp, unsigned long store_size)
 {
     struct msdos_partition *pp;
     int starts[SDEBUG_MAX_PARTS + 2], max_part_secs;
     int sectors_per_part, num_sectors, k;
     int heads_by_sects, start_sec, end_sec;
 
     /* assume partition table already zeroed */
     if ((sdebug_num_parts < 1) || (store_size < 1048576))
         return;
     if (sdebug_num_parts > SDEBUG_MAX_PARTS) {
         sdebug_num_parts = SDEBUG_MAX_PARTS;
         pr_warn("reducing partitions to %d\n", SDEBUG_MAX_PARTS);
     }
     num_sectors = (int)get_sdebug_capacity();
     sectors_per_part = (num_sectors - sdebug_sectors_per)
                / sdebug_num_parts;
     heads_by_sects = sdebug_heads * sdebug_sectors_per;
     starts[0] = sdebug_sectors_per;
     max_part_secs = sectors_per_part;
     for (k = 1; k < sdebug_num_parts; ++k) {
         starts[k] = ((k * sectors_per_part) / heads_by_sects)
                 * heads_by_sects;
         if (starts[k] - starts[k - 1] < max_part_secs)
             max_part_secs = starts[k] - starts[k - 1];
     }
     starts[sdebug_num_parts] = num_sectors;
     starts[sdebug_num_parts + 1] = 0;
 
     ramp[510] = 0x55;   /* magic partition markings */
     ramp[511] = 0xAA;
     pp = (struct msdos_partition *)(ramp + 0x1be);
     for (k = 0; starts[k + 1]; ++k, ++pp) {
         start_sec = starts[k];
         end_sec = starts[k] + max_part_secs - 1;
         pp->boot_ind = 0;
 
         pp->cyl = start_sec / heads_by_sects;
         pp->head = (start_sec - (pp->cyl * heads_by_sects))
                / sdebug_sectors_per;
         pp->sector = (start_sec % sdebug_sectors_per) + 1;
 
         pp->end_cyl = end_sec / heads_by_sects;
         pp->end_head = (end_sec - (pp->end_cyl * heads_by_sects))
                    / sdebug_sectors_per;
         pp->end_sector = (end_sec % sdebug_sectors_per) + 1;
 
         pp->start_sect = cpu_to_le32(start_sec);
         pp->nr_sects = cpu_to_le32(end_sec - start_sec + 1);
         pp->sys_ind = 0x83; /* plain Linux partition */
     }
 }
 
 static void block_unblock_all_queues(bool block)
 {
     int j;
     struct sdebug_queue *sqp;
 
     for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp)
         atomic_set(&sqp->blocked, (int)block);
 }
 
 /* Adjust (by rounding down) the sdebug_cmnd_count so abs(every_nth)-1
  * commands will be processed normally before triggers occur.
  */
 static void tweak_cmnd_count(void)
 {
     int count, modulo;
 
     modulo = abs(sdebug_every_nth);
     if (modulo < 2)
         return;
     block_unblock_all_queues(true);
     count = atomic_read(&sdebug_cmnd_count);
     atomic_set(&sdebug_cmnd_count, (count / modulo) * modulo);
     block_unblock_all_queues(false);
 }
 
 static void clear_queue_stats(void)
 {
     atomic_set(&sdebug_cmnd_count, 0);
     atomic_set(&sdebug_completions, 0);
     atomic_set(&sdebug_miss_cpus, 0);
     atomic_set(&sdebug_a_tsf, 0);
 }
 
 static bool inject_on_this_cmd(void)
 {
     if (sdebug_every_nth == 0)
         return false;
     return (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0;
 }
 
 #define INCLUSIVE_TIMING_MAX_NS 1000000     /* 1 millisecond */
 
 /* Complete the processing of the thread that queued a SCSI command to this
  * driver. It either completes the command by calling cmnd_done() or
  * schedules a hr timer or work queue then returns 0. Returns
  * SCSI_MLQUEUE_HOST_BUSY if temporarily out of resources.
  */
 static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
              int scsi_result,
              int (*pfp)(struct scsi_cmnd *,
                     struct sdebug_dev_info *),
              int delta_jiff, int ndelay)
 {
     bool new_sd_dp;
     bool inject = false;
     bool polled = scsi_cmd_to_rq(cmnd)->cmd_flags & REQ_POLLED;
     int k, num_in_q, qdepth;
     unsigned long iflags;
     u64 ns_from_boot = 0;
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
     struct scsi_device *sdp;
     struct sdebug_defer *sd_dp;
 
     if (unlikely(devip == NULL)) {
         if (scsi_result == 0)
             scsi_result = DID_NO_CONNECT << 16;
         goto respond_in_thread;
     }
     sdp = cmnd->device;
 
     if (delta_jiff == 0)
         goto respond_in_thread;
 
     sqp = get_queue(cmnd);
     spin_lock_irqsave(&sqp->qc_lock, iflags);
     if (unlikely(atomic_read(&sqp->blocked))) {
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         return SCSI_MLQUEUE_HOST_BUSY;
     }
     num_in_q = atomic_read(&devip->num_in_q);
     qdepth = cmnd->device->queue_depth;
     if (unlikely((qdepth > 0) && (num_in_q >= qdepth))) {
         if (scsi_result) {
             spin_unlock_irqrestore(&sqp->qc_lock, iflags);
             goto respond_in_thread;
         } else
             scsi_result = device_qfull_result;
     } else if (unlikely(sdebug_every_nth &&
                 (SDEBUG_OPT_RARE_TSF & sdebug_opts) &&
                 (scsi_result == 0))) {
         if ((num_in_q == (qdepth - 1)) &&
             (atomic_inc_return(&sdebug_a_tsf) >=
              abs(sdebug_every_nth))) {
             atomic_set(&sdebug_a_tsf, 0);
             inject = true;
             scsi_result = device_qfull_result;
         }
     }
 
     k = find_first_zero_bit(sqp->in_use_bm, sdebug_max_queue);
     if (unlikely(k >= sdebug_max_queue)) {
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         if (scsi_result)
             goto respond_in_thread;
         scsi_result = device_qfull_result;
         if (SDEBUG_OPT_Q_NOISE & sdebug_opts)
             sdev_printk(KERN_INFO, sdp, "%s: max_queue=%d exceeded: TASK SET FULL\n",
                     __func__, sdebug_max_queue);
         goto respond_in_thread;
     }
     set_bit(k, sqp->in_use_bm);
     atomic_inc(&devip->num_in_q);
     sqcp = &sqp->qc_arr[k];
     sqcp->a_cmnd = cmnd;
     cmnd->host_scribble = (unsigned char *)sqcp;
     sd_dp = sqcp->sd_dp;
     spin_unlock_irqrestore(&sqp->qc_lock, iflags);
 
     if (!sd_dp) {
         sd_dp = kzalloc(sizeof(*sd_dp), GFP_ATOMIC);
         if (!sd_dp) {
             atomic_dec(&devip->num_in_q);
             clear_bit(k, sqp->in_use_bm);
             return SCSI_MLQUEUE_HOST_BUSY;
         }
         new_sd_dp = true;
     } else {
         new_sd_dp = false;
     }
 
     /* Set the hostwide tag */
     if (sdebug_host_max_queue)
         sd_dp->hc_idx = get_tag(cmnd);
 
     if (polled)
         ns_from_boot = ktime_get_boottime_ns();
 
     /* one of the resp_*() response functions is called here */
     cmnd->result = pfp ? pfp(cmnd, devip) : 0;
     if (cmnd->result & SDEG_RES_IMMED_MASK) {
         cmnd->result &= ~SDEG_RES_IMMED_MASK;
         delta_jiff = ndelay = 0;
     }
     if (cmnd->result == 0 && scsi_result != 0)
         cmnd->result = scsi_result;
     if (cmnd->result == 0 && unlikely(sdebug_opts & SDEBUG_OPT_TRANSPORT_ERR)) {
         if (atomic_read(&sdeb_inject_pending)) {
             mk_sense_buffer(cmnd, ABORTED_COMMAND, TRANSPORT_PROBLEM, ACK_NAK_TO);
             atomic_set(&sdeb_inject_pending, 0);
             cmnd->result = check_condition_result;
         }
     }
 
     if (unlikely(sdebug_verbose && cmnd->result))
         sdev_printk(KERN_INFO, sdp, "%s: non-zero result=0x%x\n",
                 __func__, cmnd->result);
 
     if (delta_jiff > 0 || ndelay > 0) {
         ktime_t kt;
 
         if (delta_jiff > 0) {
             u64 ns = jiffies_to_nsecs(delta_jiff);
 
             if (sdebug_random && ns < U32_MAX) {
                 ns = prandom_u32_max((u32)ns);
             } else if (sdebug_random) {
                 ns >>= 12;  /* scale to 4 usec precision */
                 if (ns < U32_MAX)   /* over 4 hours max */
                     ns = prandom_u32_max((u32)ns);
                 ns <<= 12;
             }
             kt = ns_to_ktime(ns);
         } else {    /* ndelay has a 4.2 second max */
             kt = sdebug_random ? prandom_u32_max((u32)ndelay) :
                          (u32)ndelay;
             if (ndelay < INCLUSIVE_TIMING_MAX_NS) {
                 u64 d = ktime_get_boottime_ns() - ns_from_boot;
 
                 if (kt <= d) {  /* elapsed duration >= kt */
                     spin_lock_irqsave(&sqp->qc_lock, iflags);
                     sqcp->a_cmnd = NULL;
                     atomic_dec(&devip->num_in_q);
                     clear_bit(k, sqp->in_use_bm);
                     spin_unlock_irqrestore(&sqp->qc_lock, iflags);
                     if (new_sd_dp)
                         kfree(sd_dp);
                     /* call scsi_done() from this thread */
                     scsi_done(cmnd);
                     return 0;
                 }
                 /* otherwise reduce kt by elapsed time */
                 kt -= d;
             }
         }
         if (polled) {
             sd_dp->cmpl_ts = ktime_add(ns_to_ktime(ns_from_boot), kt);
             spin_lock_irqsave(&sqp->qc_lock, iflags);
             if (!sd_dp->init_poll) {
                 sd_dp->init_poll = true;
                 sqcp->sd_dp = sd_dp;
                 sd_dp->sqa_idx = sqp - sdebug_q_arr;
                 sd_dp->qc_idx = k;
             }
             WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_POLL);
             spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         } else {
             if (!sd_dp->init_hrt) {
                 sd_dp->init_hrt = true;
                 sqcp->sd_dp = sd_dp;
                 hrtimer_init(&sd_dp->hrt, CLOCK_MONOTONIC,
                          HRTIMER_MODE_REL_PINNED);
                 sd_dp->hrt.function = sdebug_q_cmd_hrt_complete;
                 sd_dp->sqa_idx = sqp - sdebug_q_arr;
                 sd_dp->qc_idx = k;
             }
             WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_HRT);
             /* schedule the invocation of scsi_done() for a later time */
             hrtimer_start(&sd_dp->hrt, kt, HRTIMER_MODE_REL_PINNED);
         }
         if (sdebug_statistics)
             sd_dp->issuing_cpu = raw_smp_processor_id();
     } else {    /* jdelay < 0, use work queue */
         if (unlikely((sdebug_opts & SDEBUG_OPT_CMD_ABORT) &&
                  atomic_read(&sdeb_inject_pending)))
             sd_dp->aborted = true;
         if (polled) {
             sd_dp->cmpl_ts = ns_to_ktime(ns_from_boot);
             spin_lock_irqsave(&sqp->qc_lock, iflags);
             if (!sd_dp->init_poll) {
                 sd_dp->init_poll = true;
                 sqcp->sd_dp = sd_dp;
                 sd_dp->sqa_idx = sqp - sdebug_q_arr;
                 sd_dp->qc_idx = k;
             }
             WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_POLL);
             spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         } else {
             if (!sd_dp->init_wq) {
                 sd_dp->init_wq = true;
                 sqcp->sd_dp = sd_dp;
                 sd_dp->sqa_idx = sqp - sdebug_q_arr;
                 sd_dp->qc_idx = k;
                 INIT_WORK(&sd_dp->ew.work, sdebug_q_cmd_wq_complete);
             }
             WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_WQ);
             schedule_work(&sd_dp->ew.work);
         }
         if (sdebug_statistics)
             sd_dp->issuing_cpu = raw_smp_processor_id();
         if (unlikely(sd_dp->aborted)) {
             sdev_printk(KERN_INFO, sdp, "abort request tag %d\n",
                     scsi_cmd_to_rq(cmnd)->tag);
             blk_abort_request(scsi_cmd_to_rq(cmnd));
             atomic_set(&sdeb_inject_pending, 0);
             sd_dp->aborted = false;
         }
     }
     if (unlikely((SDEBUG_OPT_Q_NOISE & sdebug_opts) && scsi_result == device_qfull_result))
         sdev_printk(KERN_INFO, sdp, "%s: num_in_q=%d +1, %s%s\n", __func__,
                 num_in_q, (inject ? "<inject> " : ""), "status: TASK SET FULL");
     return 0;
 
 respond_in_thread:  /* call back to mid-layer using invocation thread */
     cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0;
     cmnd->result &= ~SDEG_RES_IMMED_MASK;
     if (cmnd->result == 0 && scsi_result != 0)
         cmnd->result = scsi_result;
     scsi_done(cmnd);
     return 0;
 }
 
 /* Note: The following macros create attribute files in the
    /sys/module/scsi_debug/parameters directory. Unfortunately this
    driver is unaware of a change and cannot trigger auxiliary actions
    as it can when the corresponding attribute in the
    /sys/bus/pseudo/drivers/scsi_debug directory is changed.
  */
 module_param_named(add_host, sdebug_add_host, int, S_IRUGO | S_IWUSR);
 module_param_named(ato, sdebug_ato, int, S_IRUGO);
 module_param_named(cdb_len, sdebug_cdb_len, int, 0644);
 module_param_named(clustering, sdebug_clustering, bool, S_IRUGO | S_IWUSR);
 module_param_named(delay, sdebug_jdelay, int, S_IRUGO | S_IWUSR);
 module_param_named(dev_size_mb, sdebug_dev_size_mb, int, S_IRUGO);
 module_param_named(dif, sdebug_dif, int, S_IRUGO);
 module_param_named(dix, sdebug_dix, int, S_IRUGO);
 module_param_named(dsense, sdebug_dsense, int, S_IRUGO | S_IWUSR);
 module_param_named(every_nth, sdebug_every_nth, int, S_IRUGO | S_IWUSR);
 module_param_named(fake_rw, sdebug_fake_rw, int, S_IRUGO | S_IWUSR);
 module_param_named(guard, sdebug_guard, uint, S_IRUGO);
 module_param_named(host_lock, sdebug_host_lock, bool, S_IRUGO | S_IWUSR);
 module_param_named(host_max_queue, sdebug_host_max_queue, int, S_IRUGO);
 module_param_string(inq_product, sdebug_inq_product_id,
             sizeof(sdebug_inq_product_id), S_IRUGO | S_IWUSR);
 module_param_string(inq_rev, sdebug_inq_product_rev,
             sizeof(sdebug_inq_product_rev), S_IRUGO | S_IWUSR);
 module_param_string(inq_vendor, sdebug_inq_vendor_id,
             sizeof(sdebug_inq_vendor_id), S_IRUGO | S_IWUSR);
 module_param_named(lbprz, sdebug_lbprz, int, S_IRUGO);
 module_param_named(lbpu, sdebug_lbpu, int, S_IRUGO);
 module_param_named(lbpws, sdebug_lbpws, int, S_IRUGO);
 module_param_named(lbpws10, sdebug_lbpws10, int, S_IRUGO);
 module_param_named(lowest_aligned, sdebug_lowest_aligned, int, S_IRUGO);
 module_param_named(lun_format, sdebug_lun_am_i, int, S_IRUGO | S_IWUSR);
 module_param_named(max_luns, sdebug_max_luns, int, S_IRUGO | S_IWUSR);
 module_param_named(max_queue, sdebug_max_queue, int, S_IRUGO | S_IWUSR);
 module_param_named(medium_error_count, sdebug_medium_error_count, int,
            S_IRUGO | S_IWUSR);
 module_param_named(medium_error_start, sdebug_medium_error_start, int,
            S_IRUGO | S_IWUSR);
 module_param_named(ndelay, sdebug_ndelay, int, S_IRUGO | S_IWUSR);
 module_param_named(no_lun_0, sdebug_no_lun_0, int, S_IRUGO | S_IWUSR);
 module_param_named(no_rwlock, sdebug_no_rwlock, bool, S_IRUGO | S_IWUSR);
 module_param_named(no_uld, sdebug_no_uld, int, S_IRUGO);
 module_param_named(num_parts, sdebug_num_parts, int, S_IRUGO);
 module_param_named(num_tgts, sdebug_num_tgts, int, S_IRUGO | S_IWUSR);
 module_param_named(opt_blks, sdebug_opt_blks, int, S_IRUGO);
 module_param_named(opt_xferlen_exp, sdebug_opt_xferlen_exp, int, S_IRUGO);
 module_param_named(opts, sdebug_opts, int, S_IRUGO | S_IWUSR);
 module_param_named(per_host_store, sdebug_per_host_store, bool,
            S_IRUGO | S_IWUSR);
 module_param_named(physblk_exp, sdebug_physblk_exp, int, S_IRUGO);
 module_param_named(ptype, sdebug_ptype, int, S_IRUGO | S_IWUSR);
 module_param_named(random, sdebug_random, bool, S_IRUGO | S_IWUSR);
 module_param_named(removable, sdebug_removable, bool, S_IRUGO | S_IWUSR);
 module_param_named(scsi_level, sdebug_scsi_level, int, S_IRUGO);
 module_param_named(sector_size, sdebug_sector_size, int, S_IRUGO);
 module_param_named(statistics, sdebug_statistics, bool, S_IRUGO | S_IWUSR);
 module_param_named(strict, sdebug_strict, bool, S_IRUGO | S_IWUSR);
 module_param_named(submit_queues, submit_queues, int, S_IRUGO);
 module_param_named(poll_queues, poll_queues, int, S_IRUGO);
 module_param_named(tur_ms_to_ready, sdeb_tur_ms_to_ready, int, S_IRUGO);
 module_param_named(unmap_alignment, sdebug_unmap_alignment, int, S_IRUGO);
 module_param_named(unmap_granularity, sdebug_unmap_granularity, int, S_IRUGO);
 module_param_named(unmap_max_blocks, sdebug_unmap_max_blocks, int, S_IRUGO);
 module_param_named(unmap_max_desc, sdebug_unmap_max_desc, int, S_IRUGO);
 module_param_named(uuid_ctl, sdebug_uuid_ctl, int, S_IRUGO);
 module_param_named(virtual_gb, sdebug_virtual_gb, int, S_IRUGO | S_IWUSR);
 module_param_named(vpd_use_hostno, sdebug_vpd_use_hostno, int,
            S_IRUGO | S_IWUSR);
 module_param_named(wp, sdebug_wp, bool, S_IRUGO | S_IWUSR);
 module_param_named(write_same_length, sdebug_write_same_length, int,
            S_IRUGO | S_IWUSR);
 module_param_named(zbc, sdeb_zbc_model_s, charp, S_IRUGO);
 module_param_named(zone_cap_mb, sdeb_zbc_zone_cap_mb, int, S_IRUGO);
 module_param_named(zone_max_open, sdeb_zbc_max_open, int, S_IRUGO);
 module_param_named(zone_nr_conv, sdeb_zbc_nr_conv, int, S_IRUGO);
 module_param_named(zone_size_mb, sdeb_zbc_zone_size_mb, int, S_IRUGO);
 
 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
 MODULE_DESCRIPTION("SCSI debug adapter driver");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(SDEBUG_VERSION);
 
 MODULE_PARM_DESC(add_host, "add n hosts, in sysfs if negative remove host(s) (def=1)");
 MODULE_PARM_DESC(ato, "application tag ownership: 0=disk 1=host (def=1)");
 MODULE_PARM_DESC(cdb_len, "suggest CDB lengths to drivers (def=10)");
 MODULE_PARM_DESC(clustering, "when set enables larger transfers (def=0)");
 MODULE_PARM_DESC(delay, "response delay (def=1 jiffy); 0:imm, -1,-2:tiny");
 MODULE_PARM_DESC(dev_size_mb, "size in MiB of ram shared by devs(def=8)");
 MODULE_PARM_DESC(dif, "data integrity field type: 0-3 (def=0)");
 MODULE_PARM_DESC(dix, "data integrity extensions mask (def=0)");
 MODULE_PARM_DESC(dsense, "use descriptor sense format(def=0 -> fixed)");
 MODULE_PARM_DESC(every_nth, "timeout every nth command(def=0)");
 MODULE_PARM_DESC(fake_rw, "fake reads/writes instead of copying (def=0)");
 MODULE_PARM_DESC(guard, "protection checksum: 0=crc, 1=ip (def=0)");
 MODULE_PARM_DESC(host_lock, "host_lock is ignored (def=0)");
 MODULE_PARM_DESC(host_max_queue,
          "host max # of queued cmds (0 to max(def) [max_queue fixed equal for !0])");
 MODULE_PARM_DESC(inq_product, "SCSI INQUIRY product string (def=\"scsi_debug\")");
 MODULE_PARM_DESC(inq_rev, "SCSI INQUIRY revision string (def=\""
          SDEBUG_VERSION "\")");
 MODULE_PARM_DESC(inq_vendor, "SCSI INQUIRY vendor string (def=\"Linux\")");
 MODULE_PARM_DESC(lbprz,
          "on read unmapped LBs return 0 when 1 (def), return 0xff when 2");
 MODULE_PARM_DESC(lbpu, "enable LBP, support UNMAP command (def=0)");
 MODULE_PARM_DESC(lbpws, "enable LBP, support WRITE SAME(16) with UNMAP bit (def=0)");
 MODULE_PARM_DESC(lbpws10, "enable LBP, support WRITE SAME(10) with UNMAP bit (def=0)");
 MODULE_PARM_DESC(lowest_aligned, "lowest aligned lba (def=0)");
 MODULE_PARM_DESC(lun_format, "LUN format: 0->peripheral (def); 1 --> flat address method");
 MODULE_PARM_DESC(max_luns, "number of LUNs per target to simulate(def=1)");
 MODULE_PARM_DESC(max_queue, "max number of queued commands (1 to max(def))");
 MODULE_PARM_DESC(medium_error_count, "count of sectors to return follow on MEDIUM error");
 MODULE_PARM_DESC(medium_error_start, "starting sector number to return MEDIUM error");
 MODULE_PARM_DESC(ndelay, "response delay in nanoseconds (def=0 -> ignore)");
 MODULE_PARM_DESC(no_lun_0, "no LU number 0 (def=0 -> have lun 0)");
 MODULE_PARM_DESC(no_rwlock, "don't protect user data reads+writes (def=0)");
 MODULE_PARM_DESC(no_uld, "stop ULD (e.g. sd driver) attaching (def=0))");
 MODULE_PARM_DESC(num_parts, "number of partitions(def=0)");
 MODULE_PARM_DESC(num_tgts, "number of targets per host to simulate(def=1)");
 MODULE_PARM_DESC(opt_blks, "optimal transfer length in blocks (def=1024)");
 MODULE_PARM_DESC(opt_xferlen_exp, "optimal transfer length granularity exponent (def=physblk_exp)");
 MODULE_PARM_DESC(opts, "1->noise, 2->medium_err, 4->timeout, 8->recovered_err... (def=0)");
 MODULE_PARM_DESC(per_host_store, "If set, next positive add_host will get new store (def=0)");
 MODULE_PARM_DESC(physblk_exp, "physical block exponent (def=0)");
 MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues (1 to max(submit_queues - 1))");
 MODULE_PARM_DESC(ptype, "SCSI peripheral type(def=0[disk])");
 MODULE_PARM_DESC(random, "If set, uniformly randomize command duration between 0 and delay_in_ns");
 MODULE_PARM_DESC(removable, "claim to have removable media (def=0)");
 MODULE_PARM_DESC(scsi_level, "SCSI level to simulate(def=7[SPC-5])");
 MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)");
 MODULE_PARM_DESC(statistics, "collect statistics on commands, queues (def=0)");
 MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)");
 MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)");
 MODULE_PARM_DESC(tur_ms_to_ready, "TEST UNIT READY millisecs before initial good status (def=0)");
 MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba (def=0)");
 MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in blocks (def=1)");
 MODULE_PARM_DESC(unmap_max_blocks, "max # of blocks can be unmapped in one cmd (def=0xffffffff)");
 MODULE_PARM_DESC(unmap_max_desc, "max # of ranges that can be unmapped in one cmd (def=256)");
 MODULE_PARM_DESC(uuid_ctl,
          "1->use uuid for lu name, 0->don't, 2->all use same (def=0)");
 MODULE_PARM_DESC(virtual_gb, "virtual gigabyte (GiB) size (def=0 -> use dev_size_mb)");
 MODULE_PARM_DESC(vpd_use_hostno, "0 -> dev ids ignore hostno (def=1 -> unique dev ids)");
 MODULE_PARM_DESC(wp, "Write Protect (def=0)");
 MODULE_PARM_DESC(write_same_length, "Maximum blocks per WRITE SAME cmd (def=0xffff)");
 MODULE_PARM_DESC(zbc, "'none' [0]; 'aware' [1]; 'managed' [2] (def=0). Can have 'host-' prefix");
 MODULE_PARM_DESC(zone_cap_mb, "Zone capacity in MiB (def=zone size)");
 MODULE_PARM_DESC(zone_max_open, "Maximum number of open zones; [0] for no limit (def=auto)");
 MODULE_PARM_DESC(zone_nr_conv, "Number of conventional zones (def=1)");
 MODULE_PARM_DESC(zone_size_mb, "Zone size in MiB (def=auto)");
 
 #define SDEBUG_INFO_LEN 256
 static char sdebug_info[SDEBUG_INFO_LEN];
 
 static const char *scsi_debug_info(struct Scsi_Host *shp)
 {
     int k;
 
     k = scnprintf(sdebug_info, SDEBUG_INFO_LEN, "%s: version %s [%s]\n",
               my_name, SDEBUG_VERSION, sdebug_version_date);
     if (k >= (SDEBUG_INFO_LEN - 1))
         return sdebug_info;
     scnprintf(sdebug_info + k, SDEBUG_INFO_LEN - k,
           "  dev_size_mb=%d, opts=0x%x, submit_queues=%d, %s=%d",
           sdebug_dev_size_mb, sdebug_opts, submit_queues,
           "statistics", (int)sdebug_statistics);
     return sdebug_info;
 }
 
 /* 'echo <val> > /proc/scsi/scsi_debug/<host_id>' writes to opts */
 static int scsi_debug_write_info(struct Scsi_Host *host, char *buffer,
                  int length)
 {
     char arr[16];
     int opts;
     int minLen = length > 15 ? 15 : length;
 
     if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
         return -EACCES;
     memcpy(arr, buffer, minLen);
     arr[minLen] = '\0';
     if (1 != sscanf(arr, "%d", &opts))
         return -EINVAL;
     sdebug_opts = opts;
     sdebug_verbose = !!(SDEBUG_OPT_NOISE & opts);
     sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & opts);
     if (sdebug_every_nth != 0)
         tweak_cmnd_count();
     return length;
 }
 
 /* Output seen with 'cat /proc/scsi/scsi_debug/<host_id>'. It will be the
  * same for each scsi_debug host (if more than one). Some of the counters
  * output are not atomics so might be inaccurate in a busy system. */
 static int scsi_debug_show_info(struct seq_file *m, struct Scsi_Host *host)
 {
     int f, j, l;
     struct sdebug_queue *sqp;
     struct sdebug_host_info *sdhp;
 
     seq_printf(m, "scsi_debug adapter driver, version %s [%s]\n",
            SDEBUG_VERSION, sdebug_version_date);
     seq_printf(m, "num_tgts=%d, %ssize=%d MB, opts=0x%x, every_nth=%d\n",
            sdebug_num_tgts, "shared (ram) ", sdebug_dev_size_mb,
            sdebug_opts, sdebug_every_nth);
     seq_printf(m, "delay=%d, ndelay=%d, max_luns=%d, sector_size=%d %s\n",
            sdebug_jdelay, sdebug_ndelay, sdebug_max_luns,
            sdebug_sector_size, "bytes");
     seq_printf(m, "cylinders=%d, heads=%d, sectors=%d, command aborts=%d\n",
            sdebug_cylinders_per, sdebug_heads, sdebug_sectors_per,
            num_aborts);
     seq_printf(m, "RESETs: device=%d, target=%d, bus=%d, host=%d\n",
            num_dev_resets, num_target_resets, num_bus_resets,
            num_host_resets);
     seq_printf(m, "dix_reads=%d, dix_writes=%d, dif_errors=%d\n",
            dix_reads, dix_writes, dif_errors);
     seq_printf(m, "usec_in_jiffy=%lu, statistics=%d\n", TICK_NSEC / 1000,
            sdebug_statistics);
     seq_printf(m, "cmnd_count=%d, completions=%d, %s=%d, a_tsf=%d, mq_polls=%d\n",
            atomic_read(&sdebug_cmnd_count),
            atomic_read(&sdebug_completions),
            "miss_cpus", atomic_read(&sdebug_miss_cpus),
            atomic_read(&sdebug_a_tsf),
            atomic_read(&sdeb_mq_poll_count));
 
     seq_printf(m, "submit_queues=%d\n", submit_queues);
     for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
         seq_printf(m, "  queue %d:\n", j);
         f = find_first_bit(sqp->in_use_bm, sdebug_max_queue);
         if (f != sdebug_max_queue) {
             l = find_last_bit(sqp->in_use_bm, sdebug_max_queue);
             seq_printf(m, "    in_use_bm BUSY: %s: %d,%d\n",
                    "first,last bits", f, l);
         }
     }
 
     seq_printf(m, "this host_no=%d\n", host->host_no);
     if (!xa_empty(per_store_ap)) {
         bool niu;
         int idx;
         unsigned long l_idx;
         struct sdeb_store_info *sip;
 
         seq_puts(m, "\nhost list:\n");
         j = 0;
         list_for_each_entry(sdhp, &sdebug_host_list, host_list) {
             idx = sdhp->si_idx;
             seq_printf(m, "  %d: host_no=%d, si_idx=%d\n", j,
                    sdhp->shost->host_no, idx);
             ++j;
         }
         seq_printf(m, "\nper_store array [most_recent_idx=%d]:\n",
                sdeb_most_recent_idx);
         j = 0;
         xa_for_each(per_store_ap, l_idx, sip) {
             niu = xa_get_mark(per_store_ap, l_idx,
                       SDEB_XA_NOT_IN_USE);
             idx = (int)l_idx;
             seq_printf(m, "  %d: idx=%d%s\n", j, idx,
                    (niu ? "  not_in_use" : ""));
             ++j;
         }
     }
     return 0;
 }
 
 static ssize_t delay_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_jdelay);
 }
 /* Returns -EBUSY if jdelay is being changed and commands are queued. The unit
  * of delay is jiffies.
  */
 static ssize_t delay_store(struct device_driver *ddp, const char *buf,
                size_t count)
 {
     int jdelay, res;
 
     if (count > 0 && sscanf(buf, "%d", &jdelay) == 1) {
         res = count;
         if (sdebug_jdelay != jdelay) {
             int j, k;
             struct sdebug_queue *sqp;
 
             block_unblock_all_queues(true);
             for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
                  ++j, ++sqp) {
                 k = find_first_bit(sqp->in_use_bm,
                            sdebug_max_queue);
                 if (k != sdebug_max_queue) {
                     res = -EBUSY;   /* queued commands */
                     break;
                 }
             }
             if (res > 0) {
                 sdebug_jdelay = jdelay;
                 sdebug_ndelay = 0;
             }
             block_unblock_all_queues(false);
         }
         return res;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(delay);
 
 static ssize_t ndelay_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ndelay);
 }
 /* Returns -EBUSY if ndelay is being changed and commands are queued */
 /* If > 0 and accepted then sdebug_jdelay is set to JDELAY_OVERRIDDEN */
 static ssize_t ndelay_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int ndelay, res;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &ndelay)) &&
         (ndelay >= 0) && (ndelay < (1000 * 1000 * 1000))) {
         res = count;
         if (sdebug_ndelay != ndelay) {
             int j, k;
             struct sdebug_queue *sqp;
 
             block_unblock_all_queues(true);
             for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
                  ++j, ++sqp) {
                 k = find_first_bit(sqp->in_use_bm,
                            sdebug_max_queue);
                 if (k != sdebug_max_queue) {
                     res = -EBUSY;   /* queued commands */
                     break;
                 }
             }
             if (res > 0) {
                 sdebug_ndelay = ndelay;
                 sdebug_jdelay = ndelay  ? JDELAY_OVERRIDDEN
                             : DEF_JDELAY;
             }
             block_unblock_all_queues(false);
         }
         return res;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(ndelay);
 
 static ssize_t opts_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "0x%x\n", sdebug_opts);
 }
 
 static ssize_t opts_store(struct device_driver *ddp, const char *buf,
               size_t count)
 {
     int opts;
     char work[20];
 
     if (sscanf(buf, "%10s", work) == 1) {
         if (strncasecmp(work, "0x", 2) == 0) {
             if (kstrtoint(work + 2, 16, &opts) == 0)
                 goto opts_done;
         } else {
             if (kstrtoint(work, 10, &opts) == 0)
                 goto opts_done;
         }
     }
     return -EINVAL;
 opts_done:
     sdebug_opts = opts;
     sdebug_verbose = !!(SDEBUG_OPT_NOISE & opts);
     sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & opts);
     tweak_cmnd_count();
     return count;
 }
 static DRIVER_ATTR_RW(opts);
 
 static ssize_t ptype_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ptype);
 }
 static ssize_t ptype_store(struct device_driver *ddp, const char *buf,
                size_t count)
 {
     int n;
 
     /* Cannot change from or to TYPE_ZBC with sysfs */
     if (sdebug_ptype == TYPE_ZBC)
         return -EINVAL;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         if (n == TYPE_ZBC)
             return -EINVAL;
         sdebug_ptype = n;
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(ptype);
 
 static ssize_t dsense_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dsense);
 }
 static ssize_t dsense_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_dsense = n;
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(dsense);
 
 static ssize_t fake_rw_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_fake_rw);
 }
 static ssize_t fake_rw_store(struct device_driver *ddp, const char *buf,
                  size_t count)
 {
     int n, idx;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         bool want_store = (n == 0);
         struct sdebug_host_info *sdhp;
 
         n = (n > 0);
         sdebug_fake_rw = (sdebug_fake_rw > 0);
         if (sdebug_fake_rw == n)
             return count;   /* not transitioning so do nothing */
 
         if (want_store) {   /* 1 --> 0 transition, set up store */
             if (sdeb_first_idx < 0) {
                 idx = sdebug_add_store();
                 if (idx < 0)
                     return idx;
             } else {
                 idx = sdeb_first_idx;
                 xa_clear_mark(per_store_ap, idx,
                           SDEB_XA_NOT_IN_USE);
             }
             /* make all hosts use same store */
             list_for_each_entry(sdhp, &sdebug_host_list,
                         host_list) {
                 if (sdhp->si_idx != idx) {
                     xa_set_mark(per_store_ap, sdhp->si_idx,
                             SDEB_XA_NOT_IN_USE);
                     sdhp->si_idx = idx;
                 }
             }
             sdeb_most_recent_idx = idx;
         } else {    /* 0 --> 1 transition is trigger for shrink */
             sdebug_erase_all_stores(true /* apart from first */);
         }
         sdebug_fake_rw = n;
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(fake_rw);
 
 static ssize_t no_lun_0_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_no_lun_0);
 }
 static ssize_t no_lun_0_store(struct device_driver *ddp, const char *buf,
                   size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_no_lun_0 = n;
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(no_lun_0);
 
 static ssize_t num_tgts_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_tgts);
 }
 static ssize_t num_tgts_store(struct device_driver *ddp, const char *buf,
                   size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_num_tgts = n;
         sdebug_max_tgts_luns();
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(num_tgts);
 
 static ssize_t dev_size_mb_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dev_size_mb);
 }
 static DRIVER_ATTR_RO(dev_size_mb);
 
 static ssize_t per_host_store_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_per_host_store);
 }
 
 static ssize_t per_host_store_store(struct device_driver *ddp, const char *buf,
                     size_t count)
 {
     bool v;
 
     if (kstrtobool(buf, &v))
         return -EINVAL;
 
     sdebug_per_host_store = v;
     return count;
 }
 static DRIVER_ATTR_RW(per_host_store);
 
 static ssize_t num_parts_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_parts);
 }
 static DRIVER_ATTR_RO(num_parts);
 
 static ssize_t every_nth_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_every_nth);
 }
 static ssize_t every_nth_store(struct device_driver *ddp, const char *buf,
                    size_t count)
 {
     int nth;
     char work[20];
 
     if (sscanf(buf, "%10s", work) == 1) {
         if (strncasecmp(work, "0x", 2) == 0) {
             if (kstrtoint(work + 2, 16, &nth) == 0)
                 goto every_nth_done;
         } else {
             if (kstrtoint(work, 10, &nth) == 0)
                 goto every_nth_done;
         }
     }
     return -EINVAL;
 
 every_nth_done:
     sdebug_every_nth = nth;
     if (nth && !sdebug_statistics) {
         pr_info("every_nth needs statistics=1, set it\n");
         sdebug_statistics = true;
     }
     tweak_cmnd_count();
     return count;
 }
 static DRIVER_ATTR_RW(every_nth);
 
 static ssize_t lun_format_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", (int)sdebug_lun_am);
 }
 static ssize_t lun_format_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int n;
     bool changed;
 
     if (kstrtoint(buf, 0, &n))
         return -EINVAL;
     if (n >= 0) {
         if (n > (int)SAM_LUN_AM_FLAT) {
             pr_warn("only LUN address methods 0 and 1 are supported\n");
             return -EINVAL;
         }
         changed = ((int)sdebug_lun_am != n);
         sdebug_lun_am = n;
         if (changed && sdebug_scsi_level >= 5) {    /* >= SPC-3 */
             struct sdebug_host_info *sdhp;
             struct sdebug_dev_info *dp;
 
             spin_lock(&sdebug_host_list_lock);
             list_for_each_entry(sdhp, &sdebug_host_list, host_list) {
                 list_for_each_entry(dp, &sdhp->dev_info_list, dev_list) {
                     set_bit(SDEBUG_UA_LUNS_CHANGED, dp->uas_bm);
                 }
             }
             spin_unlock(&sdebug_host_list_lock);
         }
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(lun_format);
 
 static ssize_t max_luns_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_max_luns);
 }
 static ssize_t max_luns_store(struct device_driver *ddp, const char *buf,
                   size_t count)
 {
     int n;
     bool changed;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         if (n > 256) {
             pr_warn("max_luns can be no more than 256\n");
             return -EINVAL;
         }
         changed = (sdebug_max_luns != n);
         sdebug_max_luns = n;
         sdebug_max_tgts_luns();
         if (changed && (sdebug_scsi_level >= 5)) {  /* >= SPC-3 */
             struct sdebug_host_info *sdhp;
             struct sdebug_dev_info *dp;
 
             spin_lock(&sdebug_host_list_lock);
             list_for_each_entry(sdhp, &sdebug_host_list,
                         host_list) {
                 list_for_each_entry(dp, &sdhp->dev_info_list,
                             dev_list) {
                     set_bit(SDEBUG_UA_LUNS_CHANGED,
                         dp->uas_bm);
                 }
             }
             spin_unlock(&sdebug_host_list_lock);
         }
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(max_luns);
 
 static ssize_t max_queue_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_max_queue);
 }
 /* N.B. max_queue can be changed while there are queued commands. In flight
  * commands beyond the new max_queue will be completed. */
 static ssize_t max_queue_store(struct device_driver *ddp, const char *buf,
                    size_t count)
 {
     int j, n, k, a;
     struct sdebug_queue *sqp;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n > 0) &&
         (n <= SDEBUG_CANQUEUE) &&
         (sdebug_host_max_queue == 0)) {
         block_unblock_all_queues(true);
         k = 0;
         for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
              ++j, ++sqp) {
             a = find_last_bit(sqp->in_use_bm, SDEBUG_CANQUEUE);
             if (a > k)
                 k = a;
         }
         sdebug_max_queue = n;
         if (k == SDEBUG_CANQUEUE)
             atomic_set(&retired_max_queue, 0);
         else if (k >= n)
             atomic_set(&retired_max_queue, k + 1);
         else
             atomic_set(&retired_max_queue, 0);
         block_unblock_all_queues(false);
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(max_queue);
 
 static ssize_t host_max_queue_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_host_max_queue);
 }
 
 static ssize_t no_rwlock_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_no_rwlock);
 }
 
 static ssize_t no_rwlock_store(struct device_driver *ddp, const char *buf, size_t count)
 {
     bool v;
 
     if (kstrtobool(buf, &v))
         return -EINVAL;
 
     sdebug_no_rwlock = v;
     return count;
 }
 static DRIVER_ATTR_RW(no_rwlock);
 
 /*
  * Since this is used for .can_queue, and we get the hc_idx tag from the bitmap
  * in range [0, sdebug_host_max_queue), we can't change it.
  */
 static DRIVER_ATTR_RO(host_max_queue);
 
 static ssize_t no_uld_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_no_uld);
 }
 static DRIVER_ATTR_RO(no_uld);
 
 static ssize_t scsi_level_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_scsi_level);
 }
 static DRIVER_ATTR_RO(scsi_level);
 
 static ssize_t virtual_gb_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_virtual_gb);
 }
 static ssize_t virtual_gb_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int n;
     bool changed;
 
     /* Ignore capacity change for ZBC drives for now */
     if (sdeb_zbc_in_use)
         return -ENOTSUPP;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         changed = (sdebug_virtual_gb != n);
         sdebug_virtual_gb = n;
         sdebug_capacity = get_sdebug_capacity();
         if (changed) {
             struct sdebug_host_info *sdhp;
             struct sdebug_dev_info *dp;
 
             spin_lock(&sdebug_host_list_lock);
             list_for_each_entry(sdhp, &sdebug_host_list,
                         host_list) {
                 list_for_each_entry(dp, &sdhp->dev_info_list,
                             dev_list) {
                     set_bit(SDEBUG_UA_CAPACITY_CHANGED,
                         dp->uas_bm);
                 }
             }
             spin_unlock(&sdebug_host_list_lock);
         }
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(virtual_gb);
 
 static ssize_t add_host_show(struct device_driver *ddp, char *buf)
 {
     /* absolute number of hosts currently active is what is shown */
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_hosts);
 }
 
 static ssize_t add_host_store(struct device_driver *ddp, const char *buf,
                   size_t count)
 {
     bool found;
     unsigned long idx;
     struct sdeb_store_info *sip;
     bool want_phs = (sdebug_fake_rw == 0) && sdebug_per_host_store;
     int delta_hosts;
 
     if (sscanf(buf, "%d", &delta_hosts) != 1)
         return -EINVAL;
     if (delta_hosts > 0) {
         do {
             found = false;
             if (want_phs) {
                 xa_for_each_marked(per_store_ap, idx, sip,
                            SDEB_XA_NOT_IN_USE) {
                     sdeb_most_recent_idx = (int)idx;
                     found = true;
                     break;
                 }
                 if (found)  /* re-use case */
                     sdebug_add_host_helper((int)idx);
                 else
                     sdebug_do_add_host(true);
             } else {
                 sdebug_do_add_host(false);
             }
         } while (--delta_hosts);
     } else if (delta_hosts < 0) {
         do {
             sdebug_do_remove_host(false);
         } while (++delta_hosts);
     }
     return count;
 }
 static DRIVER_ATTR_RW(add_host);
 
 static ssize_t vpd_use_hostno_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_vpd_use_hostno);
 }
 static ssize_t vpd_use_hostno_store(struct device_driver *ddp, const char *buf,
                     size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_vpd_use_hostno = n;
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(vpd_use_hostno);
 
 static ssize_t statistics_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", (int)sdebug_statistics);
 }
 static ssize_t statistics_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int n;
 
     if ((count > 0) && (sscanf(buf, "%d", &n) == 1) && (n >= 0)) {
         if (n > 0)
             sdebug_statistics = true;
         else {
             clear_queue_stats();
             sdebug_statistics = false;
         }
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(statistics);
 
 static ssize_t sector_size_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%u\n", sdebug_sector_size);
 }
 static DRIVER_ATTR_RO(sector_size);
 
 static ssize_t submit_queues_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", submit_queues);
 }
 static DRIVER_ATTR_RO(submit_queues);
 
 static ssize_t dix_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dix);
 }
 static DRIVER_ATTR_RO(dix);
 
 static ssize_t dif_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dif);
 }
 static DRIVER_ATTR_RO(dif);
 
 static ssize_t guard_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%u\n", sdebug_guard);
 }
 static DRIVER_ATTR_RO(guard);
 
 static ssize_t ato_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ato);
 }
 static DRIVER_ATTR_RO(ato);
 
 static ssize_t map_show(struct device_driver *ddp, char *buf)
 {
     ssize_t count = 0;
 
     if (!scsi_debug_lbp())
         return scnprintf(buf, PAGE_SIZE, "0-%u\n",
                  sdebug_store_sectors);
 
     if (sdebug_fake_rw == 0 && !xa_empty(per_store_ap)) {
         struct sdeb_store_info *sip = xa_load(per_store_ap, 0);
 
         if (sip)
             count = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
                       (int)map_size, sip->map_storep);
     }
     buf[count++] = '\n';
     buf[count] = '\0';
 
     return count;
 }
 static DRIVER_ATTR_RO(map);
 
 static ssize_t random_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_random);
 }
 
 static ssize_t random_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     bool v;
 
     if (kstrtobool(buf, &v))
         return -EINVAL;
 
     sdebug_random = v;
     return count;
 }
 static DRIVER_ATTR_RW(random);
 
 static ssize_t removable_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_removable ? 1 : 0);
 }
 static ssize_t removable_store(struct device_driver *ddp, const char *buf,
                    size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_removable = (n > 0);
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(removable);
 
 static ssize_t host_lock_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_host_lock);
 }
 /* N.B. sdebug_host_lock does nothing, kept for backward compatibility */
 static ssize_t host_lock_store(struct device_driver *ddp, const char *buf,
                    size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_host_lock = (n > 0);
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(host_lock);
 
 static ssize_t strict_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_strict);
 }
 static ssize_t strict_store(struct device_driver *ddp, const char *buf,
                 size_t count)
 {
     int n;
 
     if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
         sdebug_strict = (n > 0);
         return count;
     }
     return -EINVAL;
 }
 static DRIVER_ATTR_RW(strict);
 
 static ssize_t uuid_ctl_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_uuid_ctl);
 }
 static DRIVER_ATTR_RO(uuid_ctl);
 
 static ssize_t cdb_len_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_cdb_len);
 }
 static ssize_t cdb_len_store(struct device_driver *ddp, const char *buf,
                  size_t count)
 {
     int ret, n;
 
     ret = kstrtoint(buf, 0, &n);
     if (ret)
         return ret;
     sdebug_cdb_len = n;
     all_config_cdb_len();
     return count;
 }
 static DRIVER_ATTR_RW(cdb_len);
 
 static const char * const zbc_model_strs_a[] = {
     [BLK_ZONED_NONE] = "none",
     [BLK_ZONED_HA]   = "host-aware",
     [BLK_ZONED_HM]   = "host-managed",
 };
 
 static const char * const zbc_model_strs_b[] = {
     [BLK_ZONED_NONE] = "no",
     [BLK_ZONED_HA]   = "aware",
     [BLK_ZONED_HM]   = "managed",
 };
 
 static const char * const zbc_model_strs_c[] = {
     [BLK_ZONED_NONE] = "0",
     [BLK_ZONED_HA]   = "1",
     [BLK_ZONED_HM]   = "2",
 };
 
 static int sdeb_zbc_model_str(const char *cp)
 {
     int res = sysfs_match_string(zbc_model_strs_a, cp);
 
     if (res < 0) {
         res = sysfs_match_string(zbc_model_strs_b, cp);
         if (res < 0) {
             res = sysfs_match_string(zbc_model_strs_c, cp);
             if (res < 0)
                 return -EINVAL;
         }
     }
     return res;
 }
 
 static ssize_t zbc_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%s\n",
              zbc_model_strs_a[sdeb_zbc_model]);
 }
 static DRIVER_ATTR_RO(zbc);
 
 static ssize_t tur_ms_to_ready_show(struct device_driver *ddp, char *buf)
 {
     return scnprintf(buf, PAGE_SIZE, "%d\n", sdeb_tur_ms_to_ready);
 }
 static DRIVER_ATTR_RO(tur_ms_to_ready);
 
 /* Note: The following array creates attribute files in the
    /sys/bus/pseudo/drivers/scsi_debug directory. The advantage of these
    files (over those found in the /sys/module/scsi_debug/parameters
    directory) is that auxiliary actions can be triggered when an attribute
    is changed. For example see: add_host_store() above.
  */
 
 static struct attribute *sdebug_drv_attrs[] = {
     &driver_attr_delay.attr,
     &driver_attr_opts.attr,
     &driver_attr_ptype.attr,
     &driver_attr_dsense.attr,
     &driver_attr_fake_rw.attr,
     &driver_attr_host_max_queue.attr,
     &driver_attr_no_lun_0.attr,
     &driver_attr_num_tgts.attr,
     &driver_attr_dev_size_mb.attr,
     &driver_attr_num_parts.attr,
     &driver_attr_every_nth.attr,
     &driver_attr_lun_format.attr,
     &driver_attr_max_luns.attr,
     &driver_attr_max_queue.attr,
     &driver_attr_no_rwlock.attr,
     &driver_attr_no_uld.attr,
     &driver_attr_scsi_level.attr,
     &driver_attr_virtual_gb.attr,
     &driver_attr_add_host.attr,
     &driver_attr_per_host_store.attr,
     &driver_attr_vpd_use_hostno.attr,
     &driver_attr_sector_size.attr,
     &driver_attr_statistics.attr,
     &driver_attr_submit_queues.attr,
     &driver_attr_dix.attr,
     &driver_attr_dif.attr,
     &driver_attr_guard.attr,
     &driver_attr_ato.attr,
     &driver_attr_map.attr,
     &driver_attr_random.attr,
     &driver_attr_removable.attr,
     &driver_attr_host_lock.attr,
     &driver_attr_ndelay.attr,
     &driver_attr_strict.attr,
     &driver_attr_uuid_ctl.attr,
     &driver_attr_cdb_len.attr,
     &driver_attr_tur_ms_to_ready.attr,
     &driver_attr_zbc.attr,
     NULL,
 };
 ATTRIBUTE_GROUPS(sdebug_drv);
 
 static struct device *pseudo_primary;
 
 static int __init scsi_debug_init(void)
 {
     bool want_store = (sdebug_fake_rw == 0);
     unsigned long sz;
     int k, ret, hosts_to_add;
     int idx = -1;
 
     ramdisk_lck_a[0] = &atomic_rw;
     ramdisk_lck_a[1] = &atomic_rw2;
     atomic_set(&retired_max_queue, 0);
 
     if (sdebug_ndelay >= 1000 * 1000 * 1000) {
         pr_warn("ndelay must be less than 1 second, ignored\n");
         sdebug_ndelay = 0;
     } else if (sdebug_ndelay > 0)
         sdebug_jdelay = JDELAY_OVERRIDDEN;
 
     switch (sdebug_sector_size) {
     case  512:
     case 1024:
     case 2048:
     case 4096:
         break;
     default:
         pr_err("invalid sector_size %d\n", sdebug_sector_size);
         return -EINVAL;
     }
 
     switch (sdebug_dif) {
     case T10_PI_TYPE0_PROTECTION:
         break;
     case T10_PI_TYPE1_PROTECTION:
     case T10_PI_TYPE2_PROTECTION:
     case T10_PI_TYPE3_PROTECTION:
         have_dif_prot = true;
         break;
 
     default:
         pr_err("dif must be 0, 1, 2 or 3\n");
         return -EINVAL;
     }
 
     if (sdebug_num_tgts < 0) {
         pr_err("num_tgts must be >= 0\n");
         return -EINVAL;
     }
 
     if (sdebug_guard > 1) {
         pr_err("guard must be 0 or 1\n");
         return -EINVAL;
     }
 
     if (sdebug_ato > 1) {
         pr_err("ato must be 0 or 1\n");
         return -EINVAL;
     }
 
     if (sdebug_physblk_exp > 15) {
         pr_err("invalid physblk_exp %u\n", sdebug_physblk_exp);
         return -EINVAL;
     }
 
     sdebug_lun_am = sdebug_lun_am_i;
     if (sdebug_lun_am > SAM_LUN_AM_FLAT) {
         pr_warn("Invalid LUN format %u, using default\n", (int)sdebug_lun_am);
         sdebug_lun_am = SAM_LUN_AM_PERIPHERAL;
     }
 
     if (sdebug_max_luns > 256) {
         if (sdebug_max_luns > 16384) {
             pr_warn("max_luns can be no more than 16384, use default\n");
             sdebug_max_luns = DEF_MAX_LUNS;
         }
         sdebug_lun_am = SAM_LUN_AM_FLAT;
     }
 
     if (sdebug_lowest_aligned > 0x3fff) {
         pr_err("lowest_aligned too big: %u\n", sdebug_lowest_aligned);
         return -EINVAL;
     }
 
     if (submit_queues < 1) {
         pr_err("submit_queues must be 1 or more\n");
         return -EINVAL;
     }
 
     if ((sdebug_max_queue > SDEBUG_CANQUEUE) || (sdebug_max_queue < 1)) {
         pr_err("max_queue must be in range [1, %d]\n", SDEBUG_CANQUEUE);
         return -EINVAL;
     }
 
     if ((sdebug_host_max_queue > SDEBUG_CANQUEUE) ||
         (sdebug_host_max_queue < 0)) {
         pr_err("host_max_queue must be in range [0 %d]\n",
                SDEBUG_CANQUEUE);
         return -EINVAL;
     }
 
     if (sdebug_host_max_queue &&
         (sdebug_max_queue != sdebug_host_max_queue)) {
         sdebug_max_queue = sdebug_host_max_queue;
         pr_warn("fixing max submit queue depth to host max queue depth, %d\n",
             sdebug_max_queue);
     }
 
     sdebug_q_arr = kcalloc(submit_queues, sizeof(struct sdebug_queue),
                    GFP_KERNEL);
     if (sdebug_q_arr == NULL)
         return -ENOMEM;
     for (k = 0; k < submit_queues; ++k)
         spin_lock_init(&sdebug_q_arr[k].qc_lock);
 
     /*
      * check for host managed zoned block device specified with
      * ptype=0x14 or zbc=XXX.
      */
     if (sdebug_ptype == TYPE_ZBC) {
         sdeb_zbc_model = BLK_ZONED_HM;
     } else if (sdeb_zbc_model_s && *sdeb_zbc_model_s) {
         k = sdeb_zbc_model_str(sdeb_zbc_model_s);
         if (k < 0) {
             ret = k;
             goto free_q_arr;
         }
         sdeb_zbc_model = k;
         switch (sdeb_zbc_model) {
         case BLK_ZONED_NONE:
         case BLK_ZONED_HA:
             sdebug_ptype = TYPE_DISK;
             break;
         case BLK_ZONED_HM:
             sdebug_ptype = TYPE_ZBC;
             break;
         default:
             pr_err("Invalid ZBC model\n");
             ret = -EINVAL;
             goto free_q_arr;
         }
     }
     if (sdeb_zbc_model != BLK_ZONED_NONE) {
         sdeb_zbc_in_use = true;
         if (sdebug_dev_size_mb == DEF_DEV_SIZE_PRE_INIT)
             sdebug_dev_size_mb = DEF_ZBC_DEV_SIZE_MB;
     }
 
     if (sdebug_dev_size_mb == DEF_DEV_SIZE_PRE_INIT)
         sdebug_dev_size_mb = DEF_DEV_SIZE_MB;
     if (sdebug_dev_size_mb < 1)
         sdebug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
     sz = (unsigned long)sdebug_dev_size_mb * 1048576;
     sdebug_store_sectors = sz / sdebug_sector_size;
     sdebug_capacity = get_sdebug_capacity();
 
     /* play around with geometry, don't waste too much on track 0 */
     sdebug_heads = 8;
     sdebug_sectors_per = 32;
     if (sdebug_dev_size_mb >= 256)
         sdebug_heads = 64;
     else if (sdebug_dev_size_mb >= 16)
         sdebug_heads = 32;
     sdebug_cylinders_per = (unsigned long)sdebug_capacity /
                    (sdebug_sectors_per * sdebug_heads);
     if (sdebug_cylinders_per >= 1024) {
         /* other LLDs do this; implies >= 1GB ram disk ... */
         sdebug_heads = 255;
         sdebug_sectors_per = 63;
         sdebug_cylinders_per = (unsigned long)sdebug_capacity /
                    (sdebug_sectors_per * sdebug_heads);
     }
     if (scsi_debug_lbp()) {
         sdebug_unmap_max_blocks =
             clamp(sdebug_unmap_max_blocks, 0U, 0xffffffffU);
 
         sdebug_unmap_max_desc =
             clamp(sdebug_unmap_max_desc, 0U, 256U);
 
         sdebug_unmap_granularity =
             clamp(sdebug_unmap_granularity, 1U, 0xffffffffU);
 
         if (sdebug_unmap_alignment &&
             sdebug_unmap_granularity <=
             sdebug_unmap_alignment) {
             pr_err("ERR: unmap_granularity <= unmap_alignment\n");
             ret = -EINVAL;
             goto free_q_arr;
         }
     }
     xa_init_flags(per_store_ap, XA_FLAGS_ALLOC | XA_FLAGS_LOCK_IRQ);
     if (want_store) {
         idx = sdebug_add_store();
         if (idx < 0) {
             ret = idx;
             goto free_q_arr;
         }
     }
 
     pseudo_primary = root_device_register("pseudo_0");
     if (IS_ERR(pseudo_primary)) {
         pr_warn("root_device_register() error\n");
         ret = PTR_ERR(pseudo_primary);
         goto free_vm;
     }
     ret = bus_register(&pseudo_lld_bus);
     if (ret < 0) {
         pr_warn("bus_register error: %d\n", ret);
         goto dev_unreg;
     }
     ret = driver_register(&sdebug_driverfs_driver);
     if (ret < 0) {
         pr_warn("driver_register error: %d\n", ret);
         goto bus_unreg;
     }
 
     hosts_to_add = sdebug_add_host;
     sdebug_add_host = 0;
 
     for (k = 0; k < hosts_to_add; k++) {
         if (want_store && k == 0) {
             ret = sdebug_add_host_helper(idx);
             if (ret < 0) {
                 pr_err("add_host_helper k=%d, error=%d\n",
                        k, -ret);
                 break;
             }
         } else {
             ret = sdebug_do_add_host(want_store &&
                          sdebug_per_host_store);
             if (ret < 0) {
                 pr_err("add_host k=%d error=%d\n", k, -ret);
                 break;
             }
         }
     }
     if (sdebug_verbose)
         pr_info("built %d host(s)\n", sdebug_num_hosts);
 
     return 0;
 
 bus_unreg:
     bus_unregister(&pseudo_lld_bus);
 dev_unreg:
     root_device_unregister(pseudo_primary);
 free_vm:
     sdebug_erase_store(idx, NULL);
 free_q_arr:
     kfree(sdebug_q_arr);
     return ret;
 }
 
 static void __exit scsi_debug_exit(void)
 {
     int k = sdebug_num_hosts;
 
     stop_all_queued();
     for (; k; k--)
         sdebug_do_remove_host(true);
     free_all_queued();
     driver_unregister(&sdebug_driverfs_driver);
     bus_unregister(&pseudo_lld_bus);
     root_device_unregister(pseudo_primary);
 
     sdebug_erase_all_stores(false);
     xa_destroy(per_store_ap);
     kfree(sdebug_q_arr);
 }
 
 device_initcall(scsi_debug_init);
 module_exit(scsi_debug_exit);
 
 static void sdebug_release_adapter(struct device *dev)
 {
     struct sdebug_host_info *sdbg_host;
 
     sdbg_host = to_sdebug_host(dev);
     kfree(sdbg_host);
 }
 
 /* idx must be valid, if sip is NULL then it will be obtained using idx */
 static void sdebug_erase_store(int idx, struct sdeb_store_info *sip)
 {
     if (idx < 0)
         return;
     if (!sip) {
         if (xa_empty(per_store_ap))
             return;
         sip = xa_load(per_store_ap, idx);
         if (!sip)
             return;
     }
     vfree(sip->map_storep);
     vfree(sip->dif_storep);
     vfree(sip->storep);
     xa_erase(per_store_ap, idx);
     kfree(sip);
 }
 
 /* Assume apart_from_first==false only in shutdown case. */
 static void sdebug_erase_all_stores(bool apart_from_first)
 {
     unsigned long idx;
     struct sdeb_store_info *sip = NULL;
 
     xa_for_each(per_store_ap, idx, sip) {
         if (apart_from_first)
             apart_from_first = false;
         else
             sdebug_erase_store(idx, sip);
     }
     if (apart_from_first)
         sdeb_most_recent_idx = sdeb_first_idx;
 }
 
 /*
  * Returns store xarray new element index (idx) if >=0 else negated errno.
  * Limit the number of stores to 65536.
  */
 static int sdebug_add_store(void)
 {
     int res;
     u32 n_idx;
     unsigned long iflags;
     unsigned long sz = (unsigned long)sdebug_dev_size_mb * 1048576;
     struct sdeb_store_info *sip = NULL;
     struct xa_limit xal = { .max = 1 << 16, .min = 0 };
 
     sip = kzalloc(sizeof(*sip), GFP_KERNEL);
     if (!sip)
         return -ENOMEM;
 
     xa_lock_irqsave(per_store_ap, iflags);
     res = __xa_alloc(per_store_ap, &n_idx, sip, xal, GFP_ATOMIC);
     if (unlikely(res < 0)) {
         xa_unlock_irqrestore(per_store_ap, iflags);
         kfree(sip);
         pr_warn("%s: xa_alloc() errno=%d\n", __func__, -res);
         return res;
     }
     sdeb_most_recent_idx = n_idx;
     if (sdeb_first_idx < 0)
         sdeb_first_idx = n_idx;
     xa_unlock_irqrestore(per_store_ap, iflags);
 
     res = -ENOMEM;
     sip->storep = vzalloc(sz);
     if (!sip->storep) {
         pr_err("user data oom\n");
         goto err;
     }
     if (sdebug_num_parts > 0)
         sdebug_build_parts(sip->storep, sz);
 
     /* DIF/DIX: what T10 calls Protection Information (PI) */
     if (sdebug_dix) {
         int dif_size;
 
         dif_size = sdebug_store_sectors * sizeof(struct t10_pi_tuple);
         sip->dif_storep = vmalloc(dif_size);
 
         pr_info("dif_storep %u bytes @ %pK\n", dif_size,
             sip->dif_storep);
 
         if (!sip->dif_storep) {
             pr_err("DIX oom\n");
             goto err;
         }
         memset(sip->dif_storep, 0xff, dif_size);
     }
     /* Logical Block Provisioning */
     if (scsi_debug_lbp()) {
         map_size = lba_to_map_index(sdebug_store_sectors - 1) + 1;
         sip->map_storep = vmalloc(array_size(sizeof(long),
                              BITS_TO_LONGS(map_size)));
 
         pr_info("%lu provisioning blocks\n", map_size);
 
         if (!sip->map_storep) {
             pr_err("LBP map oom\n");
             goto err;
         }
 
         bitmap_zero(sip->map_storep, map_size);
 
         /* Map first 1KB for partition table */
         if (sdebug_num_parts)
             map_region(sip, 0, 2);
     }
 
     rwlock_init(&sip->macc_lck);
     return (int)n_idx;
 err:
     sdebug_erase_store((int)n_idx, sip);
     pr_warn("%s: failed, errno=%d\n", __func__, -res);
     return res;
 }
 
 static int sdebug_add_host_helper(int per_host_idx)
 {
     int k, devs_per_host, idx;
     int error = -ENOMEM;
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *sdbg_devinfo, *tmp;
 
     sdbg_host = kzalloc(sizeof(*sdbg_host), GFP_KERNEL);
     if (!sdbg_host)
         return -ENOMEM;
     idx = (per_host_idx < 0) ? sdeb_first_idx : per_host_idx;
     if (xa_get_mark(per_store_ap, idx, SDEB_XA_NOT_IN_USE))
         xa_clear_mark(per_store_ap, idx, SDEB_XA_NOT_IN_USE);
     sdbg_host->si_idx = idx;
 
     INIT_LIST_HEAD(&sdbg_host->dev_info_list);
 
     devs_per_host = sdebug_num_tgts * sdebug_max_luns;
     for (k = 0; k < devs_per_host; k++) {
         sdbg_devinfo = sdebug_device_create(sdbg_host, GFP_KERNEL);
         if (!sdbg_devinfo)
             goto clean;
     }
 
     spin_lock(&sdebug_host_list_lock);
     list_add_tail(&sdbg_host->host_list, &sdebug_host_list);
     spin_unlock(&sdebug_host_list_lock);
 
     sdbg_host->dev.bus = &pseudo_lld_bus;
     sdbg_host->dev.parent = pseudo_primary;
     sdbg_host->dev.release = &sdebug_release_adapter;
     dev_set_name(&sdbg_host->dev, "adapter%d", sdebug_num_hosts);
 
     error = device_register(&sdbg_host->dev);
     if (error)
         goto clean;
 
     ++sdebug_num_hosts;
     return 0;
 
 clean:
     list_for_each_entry_safe(sdbg_devinfo, tmp, &sdbg_host->dev_info_list,
                  dev_list) {
         list_del(&sdbg_devinfo->dev_list);
         kfree(sdbg_devinfo->zstate);
         kfree(sdbg_devinfo);
     }
     kfree(sdbg_host);
     pr_warn("%s: failed, errno=%d\n", __func__, -error);
     return error;
 }
 
 static int sdebug_do_add_host(bool mk_new_store)
 {
     int ph_idx = sdeb_most_recent_idx;
 
     if (mk_new_store) {
         ph_idx = sdebug_add_store();
         if (ph_idx < 0)
             return ph_idx;
     }
     return sdebug_add_host_helper(ph_idx);
 }
 
 static void sdebug_do_remove_host(bool the_end)
 {
     int idx = -1;
     struct sdebug_host_info *sdbg_host = NULL;
     struct sdebug_host_info *sdbg_host2;
 
     spin_lock(&sdebug_host_list_lock);
     if (!list_empty(&sdebug_host_list)) {
         sdbg_host = list_entry(sdebug_host_list.prev,
                        struct sdebug_host_info, host_list);
         idx = sdbg_host->si_idx;
     }
     if (!the_end && idx >= 0) {
         bool unique = true;
 
         list_for_each_entry(sdbg_host2, &sdebug_host_list, host_list) {
             if (sdbg_host2 == sdbg_host)
                 continue;
             if (idx == sdbg_host2->si_idx) {
                 unique = false;
                 break;
             }
         }
         if (unique) {
             xa_set_mark(per_store_ap, idx, SDEB_XA_NOT_IN_USE);
             if (idx == sdeb_most_recent_idx)
                 --sdeb_most_recent_idx;
         }
     }
     if (sdbg_host)
         list_del(&sdbg_host->host_list);
     spin_unlock(&sdebug_host_list_lock);
 
     if (!sdbg_host)
         return;
 
     device_unregister(&sdbg_host->dev);
     --sdebug_num_hosts;
 }
 
 static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth)
 {
     int num_in_q = 0;
     struct sdebug_dev_info *devip;
 
     block_unblock_all_queues(true);
     devip = (struct sdebug_dev_info *)sdev->hostdata;
     if (NULL == devip) {
         block_unblock_all_queues(false);
         return  -ENODEV;
     }
     num_in_q = atomic_read(&devip->num_in_q);
 
     if (qdepth > SDEBUG_CANQUEUE) {
         qdepth = SDEBUG_CANQUEUE;
         pr_warn("%s: requested qdepth [%d] exceeds canqueue [%d], trim\n", __func__,
             qdepth, SDEBUG_CANQUEUE);
     }
     if (qdepth < 1)
         qdepth = 1;
     if (qdepth != sdev->queue_depth)
         scsi_change_queue_depth(sdev, qdepth);
 
     if (SDEBUG_OPT_Q_NOISE & sdebug_opts) {
         sdev_printk(KERN_INFO, sdev, "%s: qdepth=%d, num_in_q=%d\n",
                 __func__, qdepth, num_in_q);
     }
     block_unblock_all_queues(false);
     return sdev->queue_depth;
 }
 
 static bool fake_timeout(struct scsi_cmnd *scp)
 {
     if (0 == (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth))) {
         if (sdebug_every_nth < -1)
             sdebug_every_nth = -1;
         if (SDEBUG_OPT_TIMEOUT & sdebug_opts)
             return true; /* ignore command causing timeout */
         else if (SDEBUG_OPT_MAC_TIMEOUT & sdebug_opts &&
              scsi_medium_access_command(scp))
             return true; /* time out reads and writes */
     }
     return false;
 }
 
 /* Response to TUR or media access command when device stopped */
 static int resp_not_ready(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
     int stopped_state;
     u64 diff_ns = 0;
     ktime_t now_ts = ktime_get_boottime();
     struct scsi_device *sdp = scp->device;
 
     stopped_state = atomic_read(&devip->stopped);
     if (stopped_state == 2) {
         if (ktime_to_ns(now_ts) > ktime_to_ns(devip->create_ts)) {
             diff_ns = ktime_to_ns(ktime_sub(now_ts, devip->create_ts));
             if (diff_ns >= ((u64)sdeb_tur_ms_to_ready * 1000000)) {
                 /* tur_ms_to_ready timer extinguished */
                 atomic_set(&devip->stopped, 0);
                 return 0;
             }
         }
         mk_sense_buffer(scp, NOT_READY, LOGICAL_UNIT_NOT_READY, 0x1);
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, sdp,
                     "%s: Not ready: in process of becoming ready\n", my_name);
         if (scp->cmnd[0] == TEST_UNIT_READY) {
             u64 tur_nanosecs_to_ready = (u64)sdeb_tur_ms_to_ready * 1000000;
 
             if (diff_ns <= tur_nanosecs_to_ready)
                 diff_ns = tur_nanosecs_to_ready - diff_ns;
             else
                 diff_ns = tur_nanosecs_to_ready;
             /* As per 20-061r2 approved for spc6 by T10 on 20200716 */
             do_div(diff_ns, 1000000);   /* diff_ns becomes milliseconds */
             scsi_set_sense_information(scp->sense_buffer, SCSI_SENSE_BUFFERSIZE,
                            diff_ns);
             return check_condition_result;
         }
     }
     mk_sense_buffer(scp, NOT_READY, LOGICAL_UNIT_NOT_READY, 0x2);
     if (sdebug_verbose)
         sdev_printk(KERN_INFO, sdp, "%s: Not ready: initializing command required\n",
                 my_name);
     return check_condition_result;
 }
 
 static int sdebug_map_queues(struct Scsi_Host *shost)
 {
     int i, qoff;
 
     if (shost->nr_hw_queues == 1)
         return 0;
 
     for (i = 0, qoff = 0; i < HCTX_MAX_TYPES; i++) {
         struct blk_mq_queue_map *map = &shost->tag_set.map[i];
 
         map->nr_queues  = 0;
 
         if (i == HCTX_TYPE_DEFAULT)
             map->nr_queues = submit_queues - poll_queues;
         else if (i == HCTX_TYPE_POLL)
             map->nr_queues = poll_queues;
 
         if (!map->nr_queues) {
             BUG_ON(i == HCTX_TYPE_DEFAULT);
             continue;
         }
 
         map->queue_offset = qoff;
         blk_mq_map_queues(map);
 
         qoff += map->nr_queues;
     }
 
     return 0;
 
 }
 
 static int sdebug_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
 {
     bool first;
     bool retiring = false;
     int num_entries = 0;
     unsigned int qc_idx = 0;
     unsigned long iflags;
     ktime_t kt_from_boot = ktime_get_boottime();
     struct sdebug_queue *sqp;
     struct sdebug_queued_cmd *sqcp;
     struct scsi_cmnd *scp;
     struct sdebug_dev_info *devip;
     struct sdebug_defer *sd_dp;
 
     sqp = sdebug_q_arr + queue_num;
 
     spin_lock_irqsave(&sqp->qc_lock, iflags);
 
     qc_idx = find_first_bit(sqp->in_use_bm, sdebug_max_queue);
     if (qc_idx >= sdebug_max_queue)
         goto unlock;
 
     for (first = true; first || qc_idx + 1 < sdebug_max_queue; )   {
         if (first) {
             first = false;
             if (!test_bit(qc_idx, sqp->in_use_bm))
                 continue;
         } else {
             qc_idx = find_next_bit(sqp->in_use_bm, sdebug_max_queue, qc_idx + 1);
         }
         if (qc_idx >= sdebug_max_queue)
             break;
 
         sqcp = &sqp->qc_arr[qc_idx];
         sd_dp = sqcp->sd_dp;
         if (unlikely(!sd_dp))
             continue;
         scp = sqcp->a_cmnd;
         if (unlikely(scp == NULL)) {
             pr_err("scp is NULL, queue_num=%d, qc_idx=%u from %s\n",
                    queue_num, qc_idx, __func__);
             break;
         }
         if (READ_ONCE(sd_dp->defer_t) == SDEB_DEFER_POLL) {
             if (kt_from_boot < sd_dp->cmpl_ts)
                 continue;
 
         } else      /* ignoring non REQ_POLLED requests */
             continue;
         devip = (struct sdebug_dev_info *)scp->device->hostdata;
         if (likely(devip))
             atomic_dec(&devip->num_in_q);
         else
             pr_err("devip=NULL from %s\n", __func__);
         if (unlikely(atomic_read(&retired_max_queue) > 0))
             retiring = true;
 
         sqcp->a_cmnd = NULL;
         if (unlikely(!test_and_clear_bit(qc_idx, sqp->in_use_bm))) {
             pr_err("Unexpected completion sqp %p queue_num=%d qc_idx=%u from %s\n",
                 sqp, queue_num, qc_idx, __func__);
             break;
         }
         if (unlikely(retiring)) {   /* user has reduced max_queue */
             int k, retval;
 
             retval = atomic_read(&retired_max_queue);
             if (qc_idx >= retval) {
                 pr_err("index %d too large\n", retval);
                 break;
             }
             k = find_last_bit(sqp->in_use_bm, retval);
             if ((k < sdebug_max_queue) || (k == retval))
                 atomic_set(&retired_max_queue, 0);
             else
                 atomic_set(&retired_max_queue, k + 1);
         }
         WRITE_ONCE(sd_dp->defer_t, SDEB_DEFER_NONE);
         spin_unlock_irqrestore(&sqp->qc_lock, iflags);
         scsi_done(scp); /* callback to mid level */
         num_entries++;
         spin_lock_irqsave(&sqp->qc_lock, iflags);
         if (find_first_bit(sqp->in_use_bm, sdebug_max_queue) >= sdebug_max_queue)
             break;
     }
 
 unlock:
     spin_unlock_irqrestore(&sqp->qc_lock, iflags);
 
     if (num_entries > 0)
         atomic_add(num_entries, &sdeb_mq_poll_count);
     return num_entries;
 }
 
 static int scsi_debug_queuecommand(struct Scsi_Host *shost,
                    struct scsi_cmnd *scp)
 {
     u8 sdeb_i;
     struct scsi_device *sdp = scp->device;
     const struct opcode_info_t *oip;
     const struct opcode_info_t *r_oip;
     struct sdebug_dev_info *devip;
     u8 *cmd = scp->cmnd;
     int (*r_pfp)(struct scsi_cmnd *, struct sdebug_dev_info *);
     int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *) = NULL;
     int k, na;
     int errsts = 0;
     u64 lun_index = sdp->lun & 0x3FFF;
     u32 flags;
     u16 sa;
     u8 opcode = cmd[0];
     bool has_wlun_rl;
     bool inject_now;
 
     scsi_set_resid(scp, 0);
     if (sdebug_statistics) {
         atomic_inc(&sdebug_cmnd_count);
         inject_now = inject_on_this_cmd();
     } else {
         inject_now = false;
     }
     if (unlikely(sdebug_verbose &&
              !(SDEBUG_OPT_NO_CDB_NOISE & sdebug_opts))) {
         char b[120];
         int n, len, sb;
 
         len = scp->cmd_len;
         sb = (int)sizeof(b);
         if (len > 32)
             strcpy(b, "too long, over 32 bytes");
         else {
             for (k = 0, n = 0; k < len && n < sb; ++k)
                 n += scnprintf(b + n, sb - n, "%02x ",
                            (u32)cmd[k]);
         }
         sdev_printk(KERN_INFO, sdp, "%s: tag=%#x, cmd %s\n", my_name,
                 blk_mq_unique_tag(scsi_cmd_to_rq(scp)), b);
     }
     if (unlikely(inject_now && (sdebug_opts & SDEBUG_OPT_HOST_BUSY)))
         return SCSI_MLQUEUE_HOST_BUSY;
     has_wlun_rl = (sdp->lun == SCSI_W_LUN_REPORT_LUNS);
     if (unlikely(lun_index >= sdebug_max_luns && !has_wlun_rl))
         goto err_out;
 
     sdeb_i = opcode_ind_arr[opcode];    /* fully mapped */
     oip = &opcode_info_arr[sdeb_i];     /* safe if table consistent */
     devip = (struct sdebug_dev_info *)sdp->hostdata;
     if (unlikely(!devip)) {
         devip = find_build_dev_info(sdp);
         if (NULL == devip)
             goto err_out;
     }
     if (unlikely(inject_now && !atomic_read(&sdeb_inject_pending)))
         atomic_set(&sdeb_inject_pending, 1);
 
     na = oip->num_attached;
     r_pfp = oip->pfp;
     if (na) {   /* multiple commands with this opcode */
         r_oip = oip;
         if (FF_SA & r_oip->flags) {
             if (F_SA_LOW & oip->flags)
                 sa = 0x1f & cmd[1];
             else
                 sa = get_unaligned_be16(cmd + 8);
             for (k = 0; k <= na; oip = r_oip->arrp + k++) {
                 if (opcode == oip->opcode && sa == oip->sa)
                     break;
             }
         } else {   /* since no service action only check opcode */
             for (k = 0; k <= na; oip = r_oip->arrp + k++) {
                 if (opcode == oip->opcode)
                     break;
             }
         }
         if (k > na) {
             if (F_SA_LOW & r_oip->flags)
                 mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 4);
             else if (F_SA_HIGH & r_oip->flags)
                 mk_sense_invalid_fld(scp, SDEB_IN_CDB, 8, 7);
             else
                 mk_sense_invalid_opcode(scp);
             goto check_cond;
         }
     }   /* else (when na==0) we assume the oip is a match */
     flags = oip->flags;
     if (unlikely(F_INV_OP & flags)) {
         mk_sense_invalid_opcode(scp);
         goto check_cond;
     }
     if (unlikely(has_wlun_rl && !(F_RL_WLUN_OK & flags))) {
         if (sdebug_verbose)
             sdev_printk(KERN_INFO, sdp, "%s: Opcode 0x%x not%s\n",
                     my_name, opcode, " supported for wlun");
         mk_sense_invalid_opcode(scp);
         goto check_cond;
     }
     if (unlikely(sdebug_strict)) {  /* check cdb against mask */
         u8 rem;
         int j;
 
         for (k = 1; k < oip->len_mask[0] && k < 16; ++k) {
             rem = ~oip->len_mask[k] & cmd[k];
             if (rem) {
                 for (j = 7; j >= 0; --j, rem <<= 1) {
                     if (0x80 & rem)
                         break;
                 }
                 mk_sense_invalid_fld(scp, SDEB_IN_CDB, k, j);
                 goto check_cond;
             }
         }
     }
     if (unlikely(!(F_SKIP_UA & flags) &&
              find_first_bit(devip->uas_bm,
                     SDEBUG_NUM_UAS) != SDEBUG_NUM_UAS)) {
         errsts = make_ua(scp, devip);
         if (errsts)
             goto check_cond;
     }
     if (unlikely(((F_M_ACCESS & flags) || scp->cmnd[0] == TEST_UNIT_READY) &&
              atomic_read(&devip->stopped))) {
         errsts = resp_not_ready(scp, devip);
         if (errsts)
             goto fini;
     }
     if (sdebug_fake_rw && (F_FAKE_RW & flags))
         goto fini;
     if (unlikely(sdebug_every_nth)) {
         if (fake_timeout(scp))
             return 0;   /* ignore command: make trouble */
     }
     if (likely(oip->pfp))
         pfp = oip->pfp; /* calls a resp_* function */
     else
         pfp = r_pfp;    /* if leaf function ptr NULL, try the root's */
 
 fini:
     if (F_DELAY_OVERR & flags)  /* cmds like INQUIRY respond asap */
         return schedule_resp(scp, devip, errsts, pfp, 0, 0);
     else if ((flags & F_LONG_DELAY) && (sdebug_jdelay > 0 ||
                         sdebug_ndelay > 10000)) {
         /*
          * Skip long delays if ndelay <= 10 microseconds. Otherwise
          * for Start Stop Unit (SSU) want at least 1 second delay and
          * if sdebug_jdelay>1 want a long delay of that many seconds.
          * For Synchronize Cache want 1/20 of SSU's delay.
          */
         int jdelay = (sdebug_jdelay < 2) ? 1 : sdebug_jdelay;
         int denom = (flags & F_SYNC_DELAY) ? 20 : 1;
 
         jdelay = mult_frac(USER_HZ * jdelay, HZ, denom * USER_HZ);
         return schedule_resp(scp, devip, errsts, pfp, jdelay, 0);
     } else
         return schedule_resp(scp, devip, errsts, pfp, sdebug_jdelay,
                      sdebug_ndelay);
 check_cond:
     return schedule_resp(scp, devip, check_condition_result, NULL, 0, 0);
 err_out:
     return schedule_resp(scp, NULL, DID_NO_CONNECT << 16, NULL, 0, 0);
 }
 
 static struct scsi_host_template sdebug_driver_template = {
     .show_info =        scsi_debug_show_info,
     .write_info =       scsi_debug_write_info,
     .proc_name =        sdebug_proc_name,
     .name =         "SCSI DEBUG",
     .info =         scsi_debug_info,
     .slave_alloc =      scsi_debug_slave_alloc,
     .slave_configure =  scsi_debug_slave_configure,
     .slave_destroy =    scsi_debug_slave_destroy,
     .ioctl =        scsi_debug_ioctl,
     .queuecommand =     scsi_debug_queuecommand,
     .change_queue_depth =   sdebug_change_qdepth,
     .map_queues =       sdebug_map_queues,
     .mq_poll =      sdebug_blk_mq_poll,
     .eh_abort_handler = scsi_debug_abort,
     .eh_device_reset_handler = scsi_debug_device_reset,
     .eh_target_reset_handler = scsi_debug_target_reset,
     .eh_bus_reset_handler = scsi_debug_bus_reset,
     .eh_host_reset_handler = scsi_debug_host_reset,
     .can_queue =        SDEBUG_CANQUEUE,
     .this_id =      7,
     .sg_tablesize =     SG_MAX_SEGMENTS,
     .cmd_per_lun =      DEF_CMD_PER_LUN,
     .max_sectors =      -1U,
     .max_segment_size = -1U,
     .module =       THIS_MODULE,
     .track_queue_depth =    1,
 };
 
 static int sdebug_driver_probe(struct device *dev)
 {
     int error = 0;
     struct sdebug_host_info *sdbg_host;
     struct Scsi_Host *hpnt;
     int hprot;
 
     sdbg_host = to_sdebug_host(dev);
 
     sdebug_driver_template.can_queue = sdebug_max_queue;
     sdebug_driver_template.cmd_per_lun = sdebug_max_queue;
     if (!sdebug_clustering)
         sdebug_driver_template.dma_boundary = PAGE_SIZE - 1;
 
     hpnt = scsi_host_alloc(&sdebug_driver_template, sizeof(sdbg_host));
     if (NULL == hpnt) {
         pr_err("scsi_host_alloc failed\n");
         error = -ENODEV;
         return error;
     }
     if (submit_queues > nr_cpu_ids) {
         pr_warn("%s: trim submit_queues (was %d) to nr_cpu_ids=%u\n",
             my_name, submit_queues, nr_cpu_ids);
         submit_queues = nr_cpu_ids;
     }
     /*
      * Decide whether to tell scsi subsystem that we want mq. The
      * following should give the same answer for each host.
      */
     hpnt->nr_hw_queues = submit_queues;
     if (sdebug_host_max_queue)
         hpnt->host_tagset = 1;
 
     /* poll queues are possible for nr_hw_queues > 1 */
     if (hpnt->nr_hw_queues == 1 || (poll_queues < 1)) {
         pr_warn("%s: trim poll_queues to 0. poll_q/nr_hw = (%d/%d)\n",
              my_name, poll_queues, hpnt->nr_hw_queues);
         poll_queues = 0;
     }
 
     /*
      * Poll queues don't need interrupts, but we need at least one I/O queue
      * left over for non-polled I/O.
      * If condition not met, trim poll_queues to 1 (just for simplicity).
      */
     if (poll_queues >= submit_queues) {
         if (submit_queues < 3)
             pr_warn("%s: trim poll_queues to 1\n", my_name);
         else
             pr_warn("%s: trim poll_queues to 1. Perhaps try poll_queues=%d\n",
                 my_name, submit_queues - 1);
         poll_queues = 1;
     }
     if (poll_queues)
         hpnt->nr_maps = 3;
 
     sdbg_host->shost = hpnt;
     *((struct sdebug_host_info **)hpnt->hostdata) = sdbg_host;
     if ((hpnt->this_id >= 0) && (sdebug_num_tgts > hpnt->this_id))
         hpnt->max_id = sdebug_num_tgts + 1;
     else
         hpnt->max_id = sdebug_num_tgts;
     /* = sdebug_max_luns; */
     hpnt->max_lun = SCSI_W_LUN_REPORT_LUNS + 1;
 
     hprot = 0;
 
     switch (sdebug_dif) {
 
     case T10_PI_TYPE1_PROTECTION:
         hprot = SHOST_DIF_TYPE1_PROTECTION;
         if (sdebug_dix)
             hprot |= SHOST_DIX_TYPE1_PROTECTION;
         break;
 
     case T10_PI_TYPE2_PROTECTION:
         hprot = SHOST_DIF_TYPE2_PROTECTION;
         if (sdebug_dix)
             hprot |= SHOST_DIX_TYPE2_PROTECTION;
         break;
 
     case T10_PI_TYPE3_PROTECTION:
         hprot = SHOST_DIF_TYPE3_PROTECTION;
         if (sdebug_dix)
             hprot |= SHOST_DIX_TYPE3_PROTECTION;
         break;
 
     default:
         if (sdebug_dix)
             hprot |= SHOST_DIX_TYPE0_PROTECTION;
         break;
     }
 
     scsi_host_set_prot(hpnt, hprot);
 
     if (have_dif_prot || sdebug_dix)
         pr_info("host protection%s%s%s%s%s%s%s\n",
             (hprot & SHOST_DIF_TYPE1_PROTECTION) ? " DIF1" : "",
             (hprot & SHOST_DIF_TYPE2_PROTECTION) ? " DIF2" : "",
             (hprot & SHOST_DIF_TYPE3_PROTECTION) ? " DIF3" : "",
             (hprot & SHOST_DIX_TYPE0_PROTECTION) ? " DIX0" : "",
             (hprot & SHOST_DIX_TYPE1_PROTECTION) ? " DIX1" : "",
             (hprot & SHOST_DIX_TYPE2_PROTECTION) ? " DIX2" : "",
             (hprot & SHOST_DIX_TYPE3_PROTECTION) ? " DIX3" : "");
 
     if (sdebug_guard == 1)
         scsi_host_set_guard(hpnt, SHOST_DIX_GUARD_IP);
     else
         scsi_host_set_guard(hpnt, SHOST_DIX_GUARD_CRC);
 
     sdebug_verbose = !!(SDEBUG_OPT_NOISE & sdebug_opts);
     sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & sdebug_opts);
     if (sdebug_every_nth)   /* need stats counters for every_nth */
         sdebug_statistics = true;
     error = scsi_add_host(hpnt, &sdbg_host->dev);
     if (error) {
         pr_err("scsi_add_host failed\n");
         error = -ENODEV;
         scsi_host_put(hpnt);
     } else {
         scsi_scan_host(hpnt);
     }
 
     return error;
 }
 
 static void sdebug_driver_remove(struct device *dev)
 {
     struct sdebug_host_info *sdbg_host;
     struct sdebug_dev_info *sdbg_devinfo, *tmp;
 
     sdbg_host = to_sdebug_host(dev);
 
     scsi_remove_host(sdbg_host->shost);
 
     list_for_each_entry_safe(sdbg_devinfo, tmp, &sdbg_host->dev_info_list,
                  dev_list) {
         list_del(&sdbg_devinfo->dev_list);
         kfree(sdbg_devinfo->zstate);
         kfree(sdbg_devinfo);
     }
 
     scsi_host_put(sdbg_host->shost);
 }
 
 static int pseudo_lld_bus_match(struct device *dev,
                 struct device_driver *dev_driver)
 {
     return 1;
 }
 
 static struct bus_type pseudo_lld_bus = {
     .name = "pseudo",
     .match = pseudo_lld_bus_match,
     .probe = sdebug_driver_probe,
     .remove = sdebug_driver_remove,
     .drv_groups = sdebug_drv_groups,
 };