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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+
 /*
  * Driver for USB Mass Storage compliant devices
  *
  * Current development and maintenance by:
  *   (c) 1999-2003 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
  *
  * Developed with the assistance of:
  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
  *   (c) 2003-2009 Alan Stern (stern@rowland.harvard.edu)
  *
  * Initial work by:
  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
  *
  * usb_device_id support by Adam J. Richter (adam@yggdrasil.com):
  *   (c) 2000 Yggdrasil Computing, Inc.
  *
  * This driver is based on the 'USB Mass Storage Class' document. This
  * describes in detail the protocol used to communicate with such
  * devices.  Clearly, the designers had SCSI and ATAPI commands in
  * mind when they created this document.  The commands are all very
  * similar to commands in the SCSI-II and ATAPI specifications.
  *
  * It is important to note that in a number of cases this class
  * exhibits class-specific exemptions from the USB specification.
  * Notably the usage of NAK, STALL and ACK differs from the norm, in
  * that they are used to communicate wait, failed and OK on commands.
  *
  * Also, for certain devices, the interrupt endpoint is used to convey
  * status of a command.
  */
 
 #ifdef CONFIG_USB_STORAGE_DEBUG
 #define DEBUG
 #endif
 
 #include <linux/sched.h>
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/utsname.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
 
 #include "usb.h"
 #include "scsiglue.h"
 #include "transport.h"
 #include "protocol.h"
 #include "debug.h"
 #include "initializers.h"
 
 #include "sierra_ms.h"
 #include "option_ms.h"
 
 #if IS_ENABLED(CONFIG_USB_UAS)
 #include "uas-detect.h"
 #endif
 
 #define DRV_NAME "usb-storage"
 
 /* Some informational data */
 MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
 MODULE_DESCRIPTION("USB Mass Storage driver for Linux");
 MODULE_LICENSE("GPL");
 
 static unsigned int delay_use = 1;
 module_param(delay_use, uint, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(delay_use, "seconds to delay before using a new device");
 
 static char quirks[128];
 module_param_string(quirks, quirks, sizeof(quirks), S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(quirks, "supplemental list of device IDs and their quirks");
 
 
 /*
  * The entries in this table correspond, line for line,
  * with the entries in usb_storage_usb_ids[], defined in usual-tables.c.
  */
 
 /*
  *The vendor name should be kept at eight characters or less, and
  * the product name should be kept at 16 characters or less. If a device
  * has the US_FL_FIX_INQUIRY flag, then the vendor and product names
  * normally generated by a device through the INQUIRY response will be
  * taken from this list, and this is the reason for the above size
  * restriction. However, if the flag is not present, then you
  * are free to use as many characters as you like.
  */
 
 #define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
             vendor_name, product_name, use_protocol, use_transport, \
             init_function, Flags) \
 { \
     .vendorName = vendor_name,  \
     .productName = product_name,    \
     .useProtocol = use_protocol,    \
     .useTransport = use_transport,  \
     .initFunction = init_function,  \
 }
 
 #define COMPLIANT_DEV   UNUSUAL_DEV
 
 #define USUAL_DEV(use_protocol, use_transport) \
 { \
     .useProtocol = use_protocol,    \
     .useTransport = use_transport,  \
 }
 
 #define UNUSUAL_VENDOR_INTF(idVendor, cl, sc, pr, \
         vendor_name, product_name, use_protocol, use_transport, \
         init_function, Flags) \
 { \
     .vendorName = vendor_name,  \
     .productName = product_name,    \
     .useProtocol = use_protocol,    \
     .useTransport = use_transport,  \
     .initFunction = init_function,  \
 }
 
 static const struct us_unusual_dev us_unusual_dev_list[] = {
 #   include "unusual_devs.h"
     { }     /* Terminating entry */
 };
 
 static const struct us_unusual_dev for_dynamic_ids =
         USUAL_DEV(USB_SC_SCSI, USB_PR_BULK);
 
 #undef UNUSUAL_DEV
 #undef COMPLIANT_DEV
 #undef USUAL_DEV
 #undef UNUSUAL_VENDOR_INTF
 
 #ifdef CONFIG_LOCKDEP
 
 static struct lock_class_key us_interface_key[USB_MAXINTERFACES];
 
 static void us_set_lock_class(struct mutex *mutex,
         struct usb_interface *intf)
 {
     struct usb_device *udev = interface_to_usbdev(intf);
     struct usb_host_config *config = udev->actconfig;
     int i;
 
     for (i = 0; i < config->desc.bNumInterfaces; i++) {
         if (config->interface[i] == intf)
             break;
     }
 
     BUG_ON(i == config->desc.bNumInterfaces);
 
     lockdep_set_class(mutex, &us_interface_key[i]);
 }
 
 #else
 
 static void us_set_lock_class(struct mutex *mutex,
         struct usb_interface *intf)
 {
 }
 
 #endif
 
 #ifdef CONFIG_PM    /* Minimal support for suspend and resume */
 
 int usb_stor_suspend(struct usb_interface *iface, pm_message_t message)
 {
     struct us_data *us = usb_get_intfdata(iface);
 
     /* Wait until no command is running */
     mutex_lock(&us->dev_mutex);
 
     if (us->suspend_resume_hook)
         (us->suspend_resume_hook)(us, US_SUSPEND);
 
     /*
      * When runtime PM is working, we'll set a flag to indicate
      * whether we should autoresume when a SCSI request arrives.
      */
 
     mutex_unlock(&us->dev_mutex);
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_stor_suspend);
 
 int usb_stor_resume(struct usb_interface *iface)
 {
     struct us_data *us = usb_get_intfdata(iface);
 
     mutex_lock(&us->dev_mutex);
 
     if (us->suspend_resume_hook)
         (us->suspend_resume_hook)(us, US_RESUME);
 
     mutex_unlock(&us->dev_mutex);
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_stor_resume);
 
 int usb_stor_reset_resume(struct usb_interface *iface)
 {
     struct us_data *us = usb_get_intfdata(iface);
 
     /* Report the reset to the SCSI core */
     usb_stor_report_bus_reset(us);
 
     /*
      * If any of the subdrivers implemented a reinitialization scheme,
      * this is where the callback would be invoked.
      */
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_stor_reset_resume);
 
 #endif /* CONFIG_PM */
 
 /*
  * The next two routines get called just before and just after
  * a USB port reset, whether from this driver or a different one.
  */
 
 int usb_stor_pre_reset(struct usb_interface *iface)
 {
     struct us_data *us = usb_get_intfdata(iface);
 
     /* Make sure no command runs during the reset */
     mutex_lock(&us->dev_mutex);
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_stor_pre_reset);
 
 int usb_stor_post_reset(struct usb_interface *iface)
 {
     struct us_data *us = usb_get_intfdata(iface);
 
     /* Report the reset to the SCSI core */
     usb_stor_report_bus_reset(us);
 
     /*
      * If any of the subdrivers implemented a reinitialization scheme,
      * this is where the callback would be invoked.
      */
 
     mutex_unlock(&us->dev_mutex);
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_stor_post_reset);
 
 /*
  * fill_inquiry_response takes an unsigned char array (which must
  * be at least 36 characters) and populates the vendor name,
  * product name, and revision fields. Then the array is copied
  * into the SCSI command's response buffer (oddly enough
  * called request_buffer). data_len contains the length of the
  * data array, which again must be at least 36.
  */
 
 void fill_inquiry_response(struct us_data *us, unsigned char *data,
         unsigned int data_len)
 {
     if (data_len < 36) /* You lose. */
         return;
 
     memset(data+8, ' ', 28);
     if (data[0]&0x20) { /*
                  * USB device currently not connected. Return
                  * peripheral qualifier 001b ("...however, the
                  * physical device is not currently connected
                  * to this logical unit") and leave vendor and
                  * product identification empty. ("If the target
                  * does store some of the INQUIRY data on the
                  * device, it may return zeros or ASCII spaces
                  * (20h) in those fields until the data is
                  * available from the device.").
                  */
     } else {
         u16 bcdDevice = le16_to_cpu(us->pusb_dev->descriptor.bcdDevice);
         int n;
 
         n = strlen(us->unusual_dev->vendorName);
         memcpy(data+8, us->unusual_dev->vendorName, min(8, n));
         n = strlen(us->unusual_dev->productName);
         memcpy(data+16, us->unusual_dev->productName, min(16, n));
 
         data[32] = 0x30 + ((bcdDevice>>12) & 0x0F);
         data[33] = 0x30 + ((bcdDevice>>8) & 0x0F);
         data[34] = 0x30 + ((bcdDevice>>4) & 0x0F);
         data[35] = 0x30 + ((bcdDevice) & 0x0F);
     }
 
     usb_stor_set_xfer_buf(data, data_len, us->srb);
 }
 EXPORT_SYMBOL_GPL(fill_inquiry_response);
 
 static int usb_stor_control_thread(void * __us)
 {
     struct us_data *us = (struct us_data *)__us;
     struct Scsi_Host *host = us_to_host(us);
     struct scsi_cmnd *srb;
 
     for (;;) {
         usb_stor_dbg(us, "*** thread sleeping\n");
         if (wait_for_completion_interruptible(&us->cmnd_ready))
             break;
 
         usb_stor_dbg(us, "*** thread awakened\n");
 
         /* lock the device pointers */
         mutex_lock(&(us->dev_mutex));
 
         /* lock access to the state */
         scsi_lock(host);
 
         /* When we are called with no command pending, we're done */
         srb = us->srb;
         if (srb == NULL) {
             scsi_unlock(host);
             mutex_unlock(&us->dev_mutex);
             usb_stor_dbg(us, "-- exiting\n");
             break;
         }
 
         /* has the command timed out *already* ? */
         if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
             srb->result = DID_ABORT << 16;
             goto SkipForAbort;
         }
 
         scsi_unlock(host);
 
         /*
          * reject the command if the direction indicator
          * is UNKNOWN
          */
         if (srb->sc_data_direction == DMA_BIDIRECTIONAL) {
             usb_stor_dbg(us, "UNKNOWN data direction\n");
             srb->result = DID_ERROR << 16;
         }
 
         /*
          * reject if target != 0 or if LUN is higher than
          * the maximum known LUN
          */
         else if (srb->device->id &&
                 !(us->fflags & US_FL_SCM_MULT_TARG)) {
             usb_stor_dbg(us, "Bad target number (%d:%llu)\n",
                      srb->device->id,
                      srb->device->lun);
             srb->result = DID_BAD_TARGET << 16;
         }
 
         else if (srb->device->lun > us->max_lun) {
             usb_stor_dbg(us, "Bad LUN (%d:%llu)\n",
                      srb->device->id,
                      srb->device->lun);
             srb->result = DID_BAD_TARGET << 16;
         }
 
         /*
          * Handle those devices which need us to fake
          * their inquiry data
          */
         else if ((srb->cmnd[0] == INQUIRY) &&
                 (us->fflags & US_FL_FIX_INQUIRY)) {
             unsigned char data_ptr[36] = {
                 0x00, 0x80, 0x02, 0x02,
                 0x1F, 0x00, 0x00, 0x00};
 
             usb_stor_dbg(us, "Faking INQUIRY command\n");
             fill_inquiry_response(us, data_ptr, 36);
             srb->result = SAM_STAT_GOOD;
         }
 
         /* we've got a command, let's do it! */
         else {
             US_DEBUG(usb_stor_show_command(us, srb));
             us->proto_handler(srb, us);
             usb_mark_last_busy(us->pusb_dev);
         }
 
         /* lock access to the state */
         scsi_lock(host);
 
         /* was the command aborted? */
         if (srb->result == DID_ABORT << 16) {
 SkipForAbort:
             usb_stor_dbg(us, "scsi command aborted\n");
             srb = NULL; /* Don't call scsi_done() */
         }
 
         /*
          * If an abort request was received we need to signal that
          * the abort has finished.  The proper test for this is
          * the TIMED_OUT flag, not srb->result == DID_ABORT, because
          * the timeout might have occurred after the command had
          * already completed with a different result code.
          */
         if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
             complete(&(us->notify));
 
             /* Allow USB transfers to resume */
             clear_bit(US_FLIDX_ABORTING, &us->dflags);
             clear_bit(US_FLIDX_TIMED_OUT, &us->dflags);
         }
 
         /* finished working on this command */
         us->srb = NULL;
         scsi_unlock(host);
 
         /* unlock the device pointers */
         mutex_unlock(&us->dev_mutex);
 
         /* now that the locks are released, notify the SCSI core */
         if (srb) {
             usb_stor_dbg(us, "scsi cmd done, result=0x%x\n",
                     srb->result);
             scsi_done_direct(srb);
         }
     } /* for (;;) */
 
     /* Wait until we are told to stop */
     for (;;) {
         set_current_state(TASK_INTERRUPTIBLE);
         if (kthread_should_stop())
             break;
         schedule();
     }
     __set_current_state(TASK_RUNNING);
     return 0;
 }
 
 /***********************************************************************
  * Device probing and disconnecting
  ***********************************************************************/
 
 /* Associate our private data with the USB device */
 static int associate_dev(struct us_data *us, struct usb_interface *intf)
 {
     /* Fill in the device-related fields */
     us->pusb_dev = interface_to_usbdev(intf);
     us->pusb_intf = intf;
     us->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
     usb_stor_dbg(us, "Vendor: 0x%04x, Product: 0x%04x, Revision: 0x%04x\n",
              le16_to_cpu(us->pusb_dev->descriptor.idVendor),
              le16_to_cpu(us->pusb_dev->descriptor.idProduct),
              le16_to_cpu(us->pusb_dev->descriptor.bcdDevice));
     usb_stor_dbg(us, "Interface Subclass: 0x%02x, Protocol: 0x%02x\n",
              intf->cur_altsetting->desc.bInterfaceSubClass,
              intf->cur_altsetting->desc.bInterfaceProtocol);
 
     /* Store our private data in the interface */
     usb_set_intfdata(intf, us);
 
     /* Allocate the control/setup and DMA-mapped buffers */
     us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
     if (!us->cr)
         return -ENOMEM;
 
     us->iobuf = usb_alloc_coherent(us->pusb_dev, US_IOBUF_SIZE,
             GFP_KERNEL, &us->iobuf_dma);
     if (!us->iobuf) {
         usb_stor_dbg(us, "I/O buffer allocation failed\n");
         return -ENOMEM;
     }
     return 0;
 }
 
 /* Works only for digits and letters, but small and fast */
 #define TOLOWER(x) ((x) | 0x20)
 
 /* Adjust device flags based on the "quirks=" module parameter */
 void usb_stor_adjust_quirks(struct usb_device *udev, unsigned long *fflags)
 {
     char *p;
     u16 vid = le16_to_cpu(udev->descriptor.idVendor);
     u16 pid = le16_to_cpu(udev->descriptor.idProduct);
     unsigned f = 0;
     unsigned int mask = (US_FL_SANE_SENSE | US_FL_BAD_SENSE |
             US_FL_FIX_CAPACITY | US_FL_IGNORE_UAS |
             US_FL_CAPACITY_HEURISTICS | US_FL_IGNORE_DEVICE |
             US_FL_NOT_LOCKABLE | US_FL_MAX_SECTORS_64 |
             US_FL_CAPACITY_OK | US_FL_IGNORE_RESIDUE |
             US_FL_SINGLE_LUN | US_FL_NO_WP_DETECT |
             US_FL_NO_READ_DISC_INFO | US_FL_NO_READ_CAPACITY_16 |
             US_FL_INITIAL_READ10 | US_FL_WRITE_CACHE |
             US_FL_NO_ATA_1X | US_FL_NO_REPORT_OPCODES |
             US_FL_MAX_SECTORS_240 | US_FL_NO_REPORT_LUNS |
             US_FL_ALWAYS_SYNC);
 
     p = quirks;
     while (*p) {
         /* Each entry consists of VID:PID:flags */
         if (vid == simple_strtoul(p, &p, 16) &&
                 *p == ':' &&
                 pid == simple_strtoul(p+1, &p, 16) &&
                 *p == ':')
             break;
 
         /* Move forward to the next entry */
         while (*p) {
             if (*p++ == ',')
                 break;
         }
     }
     if (!*p)    /* No match */
         return;
 
     /* Collect the flags */
     while (*++p && *p != ',') {
         switch (TOLOWER(*p)) {
         case 'a':
             f |= US_FL_SANE_SENSE;
             break;
         case 'b':
             f |= US_FL_BAD_SENSE;
             break;
         case 'c':
             f |= US_FL_FIX_CAPACITY;
             break;
         case 'd':
             f |= US_FL_NO_READ_DISC_INFO;
             break;
         case 'e':
             f |= US_FL_NO_READ_CAPACITY_16;
             break;
         case 'f':
             f |= US_FL_NO_REPORT_OPCODES;
             break;
         case 'g':
             f |= US_FL_MAX_SECTORS_240;
             break;
         case 'h':
             f |= US_FL_CAPACITY_HEURISTICS;
             break;
         case 'i':
             f |= US_FL_IGNORE_DEVICE;
             break;
         case 'j':
             f |= US_FL_NO_REPORT_LUNS;
             break;
         case 'k':
             f |= US_FL_NO_SAME;
             break;
         case 'l':
             f |= US_FL_NOT_LOCKABLE;
             break;
         case 'm':
             f |= US_FL_MAX_SECTORS_64;
             break;
         case 'n':
             f |= US_FL_INITIAL_READ10;
             break;
         case 'o':
             f |= US_FL_CAPACITY_OK;
             break;
         case 'p':
             f |= US_FL_WRITE_CACHE;
             break;
         case 'r':
             f |= US_FL_IGNORE_RESIDUE;
             break;
         case 's':
             f |= US_FL_SINGLE_LUN;
             break;
         case 't':
             f |= US_FL_NO_ATA_1X;
             break;
         case 'u':
             f |= US_FL_IGNORE_UAS;
             break;
         case 'w':
             f |= US_FL_NO_WP_DETECT;
             break;
         case 'y':
             f |= US_FL_ALWAYS_SYNC;
             break;
         /* Ignore unrecognized flag characters */
         }
     }
     *fflags = (*fflags & ~mask) | f;
 }
 EXPORT_SYMBOL_GPL(usb_stor_adjust_quirks);
 
 /* Get the unusual_devs entries and the string descriptors */
 static int get_device_info(struct us_data *us, const struct usb_device_id *id,
         const struct us_unusual_dev *unusual_dev)
 {
     struct usb_device *dev = us->pusb_dev;
     struct usb_interface_descriptor *idesc =
         &us->pusb_intf->cur_altsetting->desc;
     struct device *pdev = &us->pusb_intf->dev;
 
     /* Store the entries */
     us->unusual_dev = unusual_dev;
     us->subclass = (unusual_dev->useProtocol == USB_SC_DEVICE) ?
             idesc->bInterfaceSubClass :
             unusual_dev->useProtocol;
     us->protocol = (unusual_dev->useTransport == USB_PR_DEVICE) ?
             idesc->bInterfaceProtocol :
             unusual_dev->useTransport;
     us->fflags = id->driver_info;
     usb_stor_adjust_quirks(us->pusb_dev, &us->fflags);
 
     if (us->fflags & US_FL_IGNORE_DEVICE) {
         dev_info(pdev, "device ignored\n");
         return -ENODEV;
     }
 
     /*
      * This flag is only needed when we're in high-speed, so let's
      * disable it if we're in full-speed
      */
     if (dev->speed != USB_SPEED_HIGH)
         us->fflags &= ~US_FL_GO_SLOW;
 
     if (us->fflags)
         dev_info(pdev, "Quirks match for vid %04x pid %04x: %lx\n",
                 le16_to_cpu(dev->descriptor.idVendor),
                 le16_to_cpu(dev->descriptor.idProduct),
                 us->fflags);
 
     /*
      * Log a message if a non-generic unusual_dev entry contains an
      * unnecessary subclass or protocol override.  This may stimulate
      * reports from users that will help us remove unneeded entries
      * from the unusual_devs.h table.
      */
     if (id->idVendor || id->idProduct) {
         static const char *msgs[3] = {
             "an unneeded SubClass entry",
             "an unneeded Protocol entry",
             "unneeded SubClass and Protocol entries"};
         struct usb_device_descriptor *ddesc = &dev->descriptor;
         int msg = -1;
 
         if (unusual_dev->useProtocol != USB_SC_DEVICE &&
             us->subclass == idesc->bInterfaceSubClass)
             msg += 1;
         if (unusual_dev->useTransport != USB_PR_DEVICE &&
             us->protocol == idesc->bInterfaceProtocol)
             msg += 2;
         if (msg >= 0 && !(us->fflags & US_FL_NEED_OVERRIDE))
             dev_notice(pdev, "This device "
                     "(%04x,%04x,%04x S %02x P %02x)"
                     " has %s in unusual_devs.h (kernel"
                     " %s)\n"
                     "   Please send a copy of this message to "
                     "<linux-usb@vger.kernel.org> and "
                     "<usb-storage@lists.one-eyed-alien.net>\n",
                     le16_to_cpu(ddesc->idVendor),
                     le16_to_cpu(ddesc->idProduct),
                     le16_to_cpu(ddesc->bcdDevice),
                     idesc->bInterfaceSubClass,
                     idesc->bInterfaceProtocol,
                     msgs[msg],
                     utsname()->release);
     }
 
     return 0;
 }
 
 /* Get the transport settings */
 static void get_transport(struct us_data *us)
 {
     switch (us->protocol) {
     case USB_PR_CB:
         us->transport_name = "Control/Bulk";
         us->transport = usb_stor_CB_transport;
         us->transport_reset = usb_stor_CB_reset;
         us->max_lun = 7;
         break;
 
     case USB_PR_CBI:
         us->transport_name = "Control/Bulk/Interrupt";
         us->transport = usb_stor_CB_transport;
         us->transport_reset = usb_stor_CB_reset;
         us->max_lun = 7;
         break;
 
     case USB_PR_BULK:
         us->transport_name = "Bulk";
         us->transport = usb_stor_Bulk_transport;
         us->transport_reset = usb_stor_Bulk_reset;
         break;
     }
 }
 
 /* Get the protocol settings */
 static void get_protocol(struct us_data *us)
 {
     switch (us->subclass) {
     case USB_SC_RBC:
         us->protocol_name = "Reduced Block Commands (RBC)";
         us->proto_handler = usb_stor_transparent_scsi_command;
         break;
 
     case USB_SC_8020:
         us->protocol_name = "8020i";
         us->proto_handler = usb_stor_pad12_command;
         us->max_lun = 0;
         break;
 
     case USB_SC_QIC:
         us->protocol_name = "QIC-157";
         us->proto_handler = usb_stor_pad12_command;
         us->max_lun = 0;
         break;
 
     case USB_SC_8070:
         us->protocol_name = "8070i";
         us->proto_handler = usb_stor_pad12_command;
         us->max_lun = 0;
         break;
 
     case USB_SC_SCSI:
         us->protocol_name = "Transparent SCSI";
         us->proto_handler = usb_stor_transparent_scsi_command;
         break;
 
     case USB_SC_UFI:
         us->protocol_name = "Uniform Floppy Interface (UFI)";
         us->proto_handler = usb_stor_ufi_command;
         break;
     }
 }
 
 /* Get the pipe settings */
 static int get_pipes(struct us_data *us)
 {
     struct usb_host_interface *alt = us->pusb_intf->cur_altsetting;
     struct usb_endpoint_descriptor *ep_in;
     struct usb_endpoint_descriptor *ep_out;
     struct usb_endpoint_descriptor *ep_int;
     int res;
 
     /*
      * Find the first endpoint of each type we need.
      * We are expecting a minimum of 2 endpoints - in and out (bulk).
      * An optional interrupt-in is OK (necessary for CBI protocol).
      * We will ignore any others.
      */
     res = usb_find_common_endpoints(alt, &ep_in, &ep_out, NULL, NULL);
     if (res) {
         usb_stor_dbg(us, "bulk endpoints not found\n");
         return res;
     }
 
     res = usb_find_int_in_endpoint(alt, &ep_int);
     if (res && us->protocol == USB_PR_CBI) {
         usb_stor_dbg(us, "interrupt endpoint not found\n");
         return res;
     }
 
     /* Calculate and store the pipe values */
     us->send_ctrl_pipe = usb_sndctrlpipe(us->pusb_dev, 0);
     us->recv_ctrl_pipe = usb_rcvctrlpipe(us->pusb_dev, 0);
     us->send_bulk_pipe = usb_sndbulkpipe(us->pusb_dev,
         usb_endpoint_num(ep_out));
     us->recv_bulk_pipe = usb_rcvbulkpipe(us->pusb_dev,
         usb_endpoint_num(ep_in));
     if (ep_int) {
         us->recv_intr_pipe = usb_rcvintpipe(us->pusb_dev,
             usb_endpoint_num(ep_int));
         us->ep_bInterval = ep_int->bInterval;
     }
     return 0;
 }
 
 /* Initialize all the dynamic resources we need */
 static int usb_stor_acquire_resources(struct us_data *us)
 {
     int p;
     struct task_struct *th;
 
     us->current_urb = usb_alloc_urb(0, GFP_KERNEL);
     if (!us->current_urb)
         return -ENOMEM;
 
     /*
      * Just before we start our control thread, initialize
      * the device if it needs initialization
      */
     if (us->unusual_dev->initFunction) {
         p = us->unusual_dev->initFunction(us);
         if (p)
             return p;
     }
 
     /* Start up our control thread */
     th = kthread_run(usb_stor_control_thread, us, "usb-storage");
     if (IS_ERR(th)) {
         dev_warn(&us->pusb_intf->dev,
                 "Unable to start control thread\n");
         return PTR_ERR(th);
     }
     us->ctl_thread = th;
 
     return 0;
 }
 
 /* Release all our dynamic resources */
 static void usb_stor_release_resources(struct us_data *us)
 {
     /*
      * Tell the control thread to exit.  The SCSI host must
      * already have been removed and the DISCONNECTING flag set
      * so that we won't accept any more commands.
      */
     usb_stor_dbg(us, "-- sending exit command to thread\n");
     complete(&us->cmnd_ready);
     if (us->ctl_thread)
         kthread_stop(us->ctl_thread);
 
     /* Call the destructor routine, if it exists */
     if (us->extra_destructor) {
         usb_stor_dbg(us, "-- calling extra_destructor()\n");
         us->extra_destructor(us->extra);
     }
 
     /* Free the extra data and the URB */
     kfree(us->extra);
     usb_free_urb(us->current_urb);
 }
 
 /* Dissociate from the USB device */
 static void dissociate_dev(struct us_data *us)
 {
     /* Free the buffers */
     kfree(us->cr);
     usb_free_coherent(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
 
     /* Remove our private data from the interface */
     usb_set_intfdata(us->pusb_intf, NULL);
 }
 
 /*
  * First stage of disconnect processing: stop SCSI scanning,
  * remove the host, and stop accepting new commands
  */
 static void quiesce_and_remove_host(struct us_data *us)
 {
     struct Scsi_Host *host = us_to_host(us);
 
     /* If the device is really gone, cut short reset delays */
     if (us->pusb_dev->state == USB_STATE_NOTATTACHED) {
         set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
         wake_up(&us->delay_wait);
     }
 
     /*
      * Prevent SCSI scanning (if it hasn't started yet)
      * or wait for the SCSI-scanning routine to stop.
      */
     cancel_delayed_work_sync(&us->scan_dwork);
 
     /* Balance autopm calls if scanning was cancelled */
     if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags))
         usb_autopm_put_interface_no_suspend(us->pusb_intf);
 
     /*
      * Removing the host will perform an orderly shutdown: caches
      * synchronized, disks spun down, etc.
      */
     scsi_remove_host(host);
 
     /*
      * Prevent any new commands from being accepted and cut short
      * reset delays.
      */
     scsi_lock(host);
     set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
     scsi_unlock(host);
     wake_up(&us->delay_wait);
 }
 
 /* Second stage of disconnect processing: deallocate all resources */
 static void release_everything(struct us_data *us)
 {
     usb_stor_release_resources(us);
     dissociate_dev(us);
 
     /*
      * Drop our reference to the host; the SCSI core will free it
      * (and "us" along with it) when the refcount becomes 0.
      */
     scsi_host_put(us_to_host(us));
 }
 
 /* Delayed-work routine to carry out SCSI-device scanning */
 static void usb_stor_scan_dwork(struct work_struct *work)
 {
     struct us_data *us = container_of(work, struct us_data,
             scan_dwork.work);
     struct device *dev = &us->pusb_intf->dev;
 
     dev_dbg(dev, "starting scan\n");
 
     /* For bulk-only devices, determine the max LUN value */
     if (us->protocol == USB_PR_BULK &&
         !(us->fflags & US_FL_SINGLE_LUN) &&
         !(us->fflags & US_FL_SCM_MULT_TARG)) {
         mutex_lock(&us->dev_mutex);
         us->max_lun = usb_stor_Bulk_max_lun(us);
         /*
          * Allow proper scanning of devices that present more than 8 LUNs
          * While not affecting other devices that may need the previous
          * behavior
          */
         if (us->max_lun >= 8)
             us_to_host(us)->max_lun = us->max_lun+1;
         mutex_unlock(&us->dev_mutex);
     }
     scsi_scan_host(us_to_host(us));
     dev_dbg(dev, "scan complete\n");
 
     /* Should we unbind if no devices were detected? */
 
     usb_autopm_put_interface(us->pusb_intf);
     clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
 }
 
 static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
 {
     struct usb_device *usb_dev = interface_to_usbdev(intf);
 
     if (usb_dev->bus->sg_tablesize) {
         return usb_dev->bus->sg_tablesize;
     }
     return SG_ALL;
 }
 
 /* First part of general USB mass-storage probing */
 int usb_stor_probe1(struct us_data **pus,
         struct usb_interface *intf,
         const struct usb_device_id *id,
         const struct us_unusual_dev *unusual_dev,
         struct scsi_host_template *sht)
 {
     struct Scsi_Host *host;
     struct us_data *us;
     int result;
 
     dev_info(&intf->dev, "USB Mass Storage device detected\n");
 
     /*
      * Ask the SCSI layer to allocate a host structure, with extra
      * space at the end for our private us_data structure.
      */
     host = scsi_host_alloc(sht, sizeof(*us));
     if (!host) {
         dev_warn(&intf->dev, "Unable to allocate the scsi host\n");
         return -ENOMEM;
     }
 
     /*
      * Allow 16-byte CDBs and thus > 2TB
      */
     host->max_cmd_len = 16;
     host->sg_tablesize = usb_stor_sg_tablesize(intf);
     *pus = us = host_to_us(host);
     mutex_init(&(us->dev_mutex));
     us_set_lock_class(&us->dev_mutex, intf);
     init_completion(&us->cmnd_ready);
     init_completion(&(us->notify));
     init_waitqueue_head(&us->delay_wait);
     INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork);
 
     /* Associate the us_data structure with the USB device */
     result = associate_dev(us, intf);
     if (result)
         goto BadDevice;
 
     /* Get the unusual_devs entries and the descriptors */
     result = get_device_info(us, id, unusual_dev);
     if (result)
         goto BadDevice;
 
     /* Get standard transport and protocol settings */
     get_transport(us);
     get_protocol(us);
 
     /*
      * Give the caller a chance to fill in specialized transport
      * or protocol settings.
      */
     return 0;
 
 BadDevice:
     usb_stor_dbg(us, "storage_probe() failed\n");
     release_everything(us);
     return result;
 }
 EXPORT_SYMBOL_GPL(usb_stor_probe1);
 
 /* Second part of general USB mass-storage probing */
 int usb_stor_probe2(struct us_data *us)
 {
     int result;
     struct device *dev = &us->pusb_intf->dev;
 
     /* Make sure the transport and protocol have both been set */
     if (!us->transport || !us->proto_handler) {
         result = -ENXIO;
         goto BadDevice;
     }
     usb_stor_dbg(us, "Transport: %s\n", us->transport_name);
     usb_stor_dbg(us, "Protocol: %s\n", us->protocol_name);
 
     if (us->fflags & US_FL_SCM_MULT_TARG) {
         /*
          * SCM eUSCSI bridge devices can have different numbers
          * of LUNs on different targets; allow all to be probed.
          */
         us->max_lun = 7;
         /* The eUSCSI itself has ID 7, so avoid scanning that */
         us_to_host(us)->this_id = 7;
         /* max_id is 8 initially, so no need to set it here */
     } else {
         /* In the normal case there is only a single target */
         us_to_host(us)->max_id = 1;
         /*
          * Like Windows, we won't store the LUN bits in CDB[1] for
          * SCSI-2 devices using the Bulk-Only transport (even though
          * this violates the SCSI spec).
          */
         if (us->transport == usb_stor_Bulk_transport)
             us_to_host(us)->no_scsi2_lun_in_cdb = 1;
     }
 
     /* fix for single-lun devices */
     if (us->fflags & US_FL_SINGLE_LUN)
         us->max_lun = 0;
 
     /* Find the endpoints and calculate pipe values */
     result = get_pipes(us);
     if (result)
         goto BadDevice;
 
     /*
      * If the device returns invalid data for the first READ(10)
      * command, indicate the command should be retried.
      */
     if (us->fflags & US_FL_INITIAL_READ10)
         set_bit(US_FLIDX_REDO_READ10, &us->dflags);
 
     /* Acquire all the other resources and add the host */
     result = usb_stor_acquire_resources(us);
     if (result)
         goto BadDevice;
     usb_autopm_get_interface_no_resume(us->pusb_intf);
     snprintf(us->scsi_name, sizeof(us->scsi_name), "usb-storage %s",
                     dev_name(&us->pusb_intf->dev));
     result = scsi_add_host(us_to_host(us), dev);
     if (result) {
         dev_warn(dev,
                 "Unable to add the scsi host\n");
         goto HostAddErr;
     }
 
     /* Submit the delayed_work for SCSI-device scanning */
     set_bit(US_FLIDX_SCAN_PENDING, &us->dflags);
 
     if (delay_use > 0)
         dev_dbg(dev, "waiting for device to settle before scanning\n");
     queue_delayed_work(system_freezable_wq, &us->scan_dwork,
             delay_use * HZ);
     return 0;
 
     /* We come here if there are any problems */
 HostAddErr:
     usb_autopm_put_interface_no_suspend(us->pusb_intf);
 BadDevice:
     usb_stor_dbg(us, "storage_probe() failed\n");
     release_everything(us);
     return result;
 }
 EXPORT_SYMBOL_GPL(usb_stor_probe2);
 
 /* Handle a USB mass-storage disconnect */
 void usb_stor_disconnect(struct usb_interface *intf)
 {
     struct us_data *us = usb_get_intfdata(intf);
 
     quiesce_and_remove_host(us);
     release_everything(us);
 }
 EXPORT_SYMBOL_GPL(usb_stor_disconnect);
 
 static struct scsi_host_template usb_stor_host_template;
 
 /* The main probe routine for standard devices */
 static int storage_probe(struct usb_interface *intf,
              const struct usb_device_id *id)
 {
     const struct us_unusual_dev *unusual_dev;
     struct us_data *us;
     int result;
     int size;
 
     /* If uas is enabled and this device can do uas then ignore it. */
 #if IS_ENABLED(CONFIG_USB_UAS)
     if (uas_use_uas_driver(intf, id, NULL))
         return -ENXIO;
 #endif
 
     /*
      * If the device isn't standard (is handled by a subdriver
      * module) then don't accept it.
      */
     if (usb_usual_ignore_device(intf))
         return -ENXIO;
 
     /*
      * Call the general probe procedures.
      *
      * The unusual_dev_list array is parallel to the usb_storage_usb_ids
      * table, so we use the index of the id entry to find the
      * corresponding unusual_devs entry.
      */
 
     size = ARRAY_SIZE(us_unusual_dev_list);
     if (id >= usb_storage_usb_ids && id < usb_storage_usb_ids + size) {
         unusual_dev = (id - usb_storage_usb_ids) + us_unusual_dev_list;
     } else {
         unusual_dev = &for_dynamic_ids;
 
         dev_dbg(&intf->dev, "Use Bulk-Only transport with the Transparent SCSI protocol for dynamic id: 0x%04x 0x%04x\n",
             id->idVendor, id->idProduct);
     }
 
     result = usb_stor_probe1(&us, intf, id, unusual_dev,
                  &usb_stor_host_template);
     if (result)
         return result;
 
     /* No special transport or protocol settings in the main module */
 
     result = usb_stor_probe2(us);
     return result;
 }
 
 static struct usb_driver usb_storage_driver = {
     .name =     DRV_NAME,
     .probe =    storage_probe,
     .disconnect =   usb_stor_disconnect,
     .suspend =  usb_stor_suspend,
     .resume =   usb_stor_resume,
     .reset_resume = usb_stor_reset_resume,
     .pre_reset =    usb_stor_pre_reset,
     .post_reset =   usb_stor_post_reset,
     .id_table = usb_storage_usb_ids,
     .supports_autosuspend = 1,
     .soft_unbind =  1,
 };
 
 module_usb_stor_driver(usb_storage_driver, usb_stor_host_template, DRV_NAME);

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