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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 */
 /*
  * Copyright 1996, 1997, 1998 Hans Reiser, see reiserfs/README for
  * licensing and copyright details
  */
 
 #include <linux/reiserfs_fs.h>
 
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/sched.h>
 #include <linux/bug.h>
 #include <linux/workqueue.h>
 #include <asm/unaligned.h>
 #include <linux/bitops.h>
 #include <linux/proc_fs.h>
 #include <linux/buffer_head.h>
 
 /* the 32 bit compat definitions with int argument */
 #define REISERFS_IOC32_UNPACK       _IOW(0xCD, 1, int)
 #define REISERFS_IOC32_GETVERSION   FS_IOC32_GETVERSION
 #define REISERFS_IOC32_SETVERSION   FS_IOC32_SETVERSION
 
 struct reiserfs_journal_list;
 
 /* bitmasks for i_flags field in reiserfs-specific part of inode */
 typedef enum {
     /*
      * this says what format of key do all items (but stat data) of
      * an object have.  If this is set, that format is 3.6 otherwise - 3.5
      */
     i_item_key_version_mask = 0x0001,
 
     /*
      * If this is unset, object has 3.5 stat data, otherwise,
      * it has 3.6 stat data with 64bit size, 32bit nlink etc.
      */
     i_stat_data_version_mask = 0x0002,
 
     /* file might need tail packing on close */
     i_pack_on_close_mask = 0x0004,
 
     /* don't pack tail of file */
     i_nopack_mask = 0x0008,
 
     /*
      * If either of these are set, "safe link" was created for this
      * file during truncate or unlink. Safe link is used to avoid
      * leakage of disk space on crash with some files open, but unlinked.
      */
     i_link_saved_unlink_mask = 0x0010,
     i_link_saved_truncate_mask = 0x0020,
 
     i_has_xattr_dir = 0x0040,
     i_data_log = 0x0080,
 } reiserfs_inode_flags;
 
 struct reiserfs_inode_info {
     __u32 i_key[4];     /* key is still 4 32 bit integers */
 
     /*
      * transient inode flags that are never stored on disk. Bitmasks
      * for this field are defined above.
      */
     __u32 i_flags;
 
     /* offset of first byte stored in direct item. */
     __u32 i_first_direct_byte;
 
     /* copy of persistent inode flags read from sd_attrs. */
     __u32 i_attrs;
 
     /* first unused block of a sequence of unused blocks */
     int i_prealloc_block;
     int i_prealloc_count;   /* length of that sequence */
 
     /* per-transaction list of inodes which  have preallocated blocks */
     struct list_head i_prealloc_list;
 
     /*
      * new_packing_locality is created; new blocks for the contents
      * of this directory should be displaced
      */
     unsigned new_packing_locality:1;
 
     /*
      * we use these for fsync or O_SYNC to decide which transaction
      * needs to be committed in order for this inode to be properly
      * flushed
      */
     unsigned int i_trans_id;
 
     struct reiserfs_journal_list *i_jl;
     atomic_t openers;
     struct mutex tailpack;
 #ifdef CONFIG_REISERFS_FS_XATTR
     struct rw_semaphore i_xattr_sem;
 #endif
 #ifdef CONFIG_QUOTA
     struct dquot *i_dquot[MAXQUOTAS];
 #endif
 
     struct inode vfs_inode;
 };
 
 typedef enum {
     reiserfs_attrs_cleared = 0x00000001,
 } reiserfs_super_block_flags;
 
 /*
  * struct reiserfs_super_block accessors/mutators since this is a disk
  * structure, it will always be in little endian format.
  */
 #define sb_block_count(sbp)         (le32_to_cpu((sbp)->s_v1.s_block_count))
 #define set_sb_block_count(sbp,v)   ((sbp)->s_v1.s_block_count = cpu_to_le32(v))
 #define sb_free_blocks(sbp)         (le32_to_cpu((sbp)->s_v1.s_free_blocks))
 #define set_sb_free_blocks(sbp,v)   ((sbp)->s_v1.s_free_blocks = cpu_to_le32(v))
 #define sb_root_block(sbp)          (le32_to_cpu((sbp)->s_v1.s_root_block))
 #define set_sb_root_block(sbp,v)    ((sbp)->s_v1.s_root_block = cpu_to_le32(v))
 
 #define sb_jp_journal_1st_block(sbp)  \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_1st_block))
 #define set_sb_jp_journal_1st_block(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_1st_block = cpu_to_le32(v))
 #define sb_jp_journal_dev(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_dev))
 #define set_sb_jp_journal_dev(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_dev = cpu_to_le32(v))
 #define sb_jp_journal_size(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_size))
 #define set_sb_jp_journal_size(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_size = cpu_to_le32(v))
 #define sb_jp_journal_trans_max(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_trans_max))
 #define set_sb_jp_journal_trans_max(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_trans_max = cpu_to_le32(v))
 #define sb_jp_journal_magic(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_magic))
 #define set_sb_jp_journal_magic(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_magic = cpu_to_le32(v))
 #define sb_jp_journal_max_batch(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_max_batch))
 #define set_sb_jp_journal_max_batch(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_max_batch = cpu_to_le32(v))
 #define sb_jp_jourmal_max_commit_age(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_journal.jp_journal_max_commit_age))
 #define set_sb_jp_journal_max_commit_age(sbp,v) \
               ((sbp)->s_v1.s_journal.jp_journal_max_commit_age = cpu_to_le32(v))
 
 #define sb_blocksize(sbp)          (le16_to_cpu((sbp)->s_v1.s_blocksize))
 #define set_sb_blocksize(sbp,v)    ((sbp)->s_v1.s_blocksize = cpu_to_le16(v))
 #define sb_oid_maxsize(sbp)        (le16_to_cpu((sbp)->s_v1.s_oid_maxsize))
 #define set_sb_oid_maxsize(sbp,v)  ((sbp)->s_v1.s_oid_maxsize = cpu_to_le16(v))
 #define sb_oid_cursize(sbp)        (le16_to_cpu((sbp)->s_v1.s_oid_cursize))
 #define set_sb_oid_cursize(sbp,v)  ((sbp)->s_v1.s_oid_cursize = cpu_to_le16(v))
 #define sb_umount_state(sbp)       (le16_to_cpu((sbp)->s_v1.s_umount_state))
 #define set_sb_umount_state(sbp,v) ((sbp)->s_v1.s_umount_state = cpu_to_le16(v))
 #define sb_fs_state(sbp)           (le16_to_cpu((sbp)->s_v1.s_fs_state))
 #define set_sb_fs_state(sbp,v)     ((sbp)->s_v1.s_fs_state = cpu_to_le16(v))
 #define sb_hash_function_code(sbp) \
               (le32_to_cpu((sbp)->s_v1.s_hash_function_code))
 #define set_sb_hash_function_code(sbp,v) \
               ((sbp)->s_v1.s_hash_function_code = cpu_to_le32(v))
 #define sb_tree_height(sbp)        (le16_to_cpu((sbp)->s_v1.s_tree_height))
 #define set_sb_tree_height(sbp,v)  ((sbp)->s_v1.s_tree_height = cpu_to_le16(v))
 #define sb_bmap_nr(sbp)            (le16_to_cpu((sbp)->s_v1.s_bmap_nr))
 #define set_sb_bmap_nr(sbp,v)      ((sbp)->s_v1.s_bmap_nr = cpu_to_le16(v))
 #define sb_version(sbp)            (le16_to_cpu((sbp)->s_v1.s_version))
 #define set_sb_version(sbp,v)      ((sbp)->s_v1.s_version = cpu_to_le16(v))
 
 #define sb_mnt_count(sbp)      (le16_to_cpu((sbp)->s_mnt_count))
 #define set_sb_mnt_count(sbp, v)   ((sbp)->s_mnt_count = cpu_to_le16(v))
 
 #define sb_reserved_for_journal(sbp) \
               (le16_to_cpu((sbp)->s_v1.s_reserved_for_journal))
 #define set_sb_reserved_for_journal(sbp,v) \
               ((sbp)->s_v1.s_reserved_for_journal = cpu_to_le16(v))
 
 /* LOGGING -- */
 
 /*
  * These all interelate for performance.
  *
  * If the journal block count is smaller than n transactions, you lose speed.
  * I don't know what n is yet, I'm guessing 8-16.
  *
  * typical transaction size depends on the application, how often fsync is
  * called, and how many metadata blocks you dirty in a 30 second period.
  * The more small files (<16k) you use, the larger your transactions will
  * be.
  *
  * If your journal fills faster than dirty buffers get flushed to disk, it
  * must flush them before allowing the journal to wrap, which slows things
  * down.  If you need high speed meta data updates, the journal should be
  * big enough to prevent wrapping before dirty meta blocks get to disk.
  *
  * If the batch max is smaller than the transaction max, you'll waste space
  * at the end of the journal because journal_end sets the next transaction
  * to start at 0 if the next transaction has any chance of wrapping.
  *
  * The large the batch max age, the better the speed, and the more meta
  * data changes you'll lose after a crash.
  */
 
 /* don't mess with these for a while */
 /* we have a node size define somewhere in reiserfs_fs.h. -Hans */
 #define JOURNAL_BLOCK_SIZE  4096    /* BUG gotta get rid of this */
 #define JOURNAL_MAX_CNODE   1500    /* max cnodes to allocate. */
 #define JOURNAL_HASH_SIZE 8192
 
 /* number of copies of the bitmaps to have floating.  Must be >= 2 */
 #define JOURNAL_NUM_BITMAPS 5
 
 /*
  * One of these for every block in every transaction
  * Each one is in two hash tables.  First, a hash of the current transaction,
  * and after journal_end, a hash of all the in memory transactions.
  * next and prev are used by the current transaction (journal_hash).
  * hnext and hprev are used by journal_list_hash.  If a block is in more
  * than one transaction, the journal_list_hash links it in multiple times.
  * This allows flush_journal_list to remove just the cnode belonging to a
  * given transaction.
  */
 struct reiserfs_journal_cnode {
     struct buffer_head *bh; /* real buffer head */
     struct super_block *sb; /* dev of real buffer head */
 
     /* block number of real buffer head, == 0 when buffer on disk */
     __u32 blocknr;
 
     unsigned long state;
 
     /* journal list this cnode lives in */
     struct reiserfs_journal_list *jlist;
 
     struct reiserfs_journal_cnode *next;    /* next in transaction list */
     struct reiserfs_journal_cnode *prev;    /* prev in transaction list */
     struct reiserfs_journal_cnode *hprev;   /* prev in hash list */
     struct reiserfs_journal_cnode *hnext;   /* next in hash list */
 };
 
 struct reiserfs_bitmap_node {
     int id;
     char *data;
     struct list_head list;
 };
 
 struct reiserfs_list_bitmap {
     struct reiserfs_journal_list *journal_list;
     struct reiserfs_bitmap_node **bitmaps;
 };
 
 /*
  * one of these for each transaction.  The most important part here is the
  * j_realblock.  this list of cnodes is used to hash all the blocks in all
  * the commits, to mark all the real buffer heads dirty once all the commits
  * hit the disk, and to make sure every real block in a transaction is on
  * disk before allowing the log area to be overwritten
  */
 struct reiserfs_journal_list {
     unsigned long j_start;
     unsigned long j_state;
     unsigned long j_len;
     atomic_t j_nonzerolen;
     atomic_t j_commit_left;
 
     /* all commits older than this on disk */
     atomic_t j_older_commits_done;
 
     struct mutex j_commit_mutex;
     unsigned int j_trans_id;
     time64_t j_timestamp; /* write-only but useful for crash dump analysis */
     struct reiserfs_list_bitmap *j_list_bitmap;
     struct buffer_head *j_commit_bh;    /* commit buffer head */
     struct reiserfs_journal_cnode *j_realblock;
     struct reiserfs_journal_cnode *j_freedlist; /* list of buffers that were freed during this trans.  free each of these on flush */
     /* time ordered list of all active transactions */
     struct list_head j_list;
 
     /*
      * time ordered list of all transactions we haven't tried
      * to flush yet
      */
     struct list_head j_working_list;
 
     /* list of tail conversion targets in need of flush before commit */
     struct list_head j_tail_bh_list;
 
     /* list of data=ordered buffers in need of flush before commit */
     struct list_head j_bh_list;
     int j_refcount;
 };
 
 struct reiserfs_journal {
     struct buffer_head **j_ap_blocks;   /* journal blocks on disk */
     /* newest journal block */
     struct reiserfs_journal_cnode *j_last;
 
     /* oldest journal block.  start here for traverse */
     struct reiserfs_journal_cnode *j_first;
 
     struct block_device *j_dev_bd;
     fmode_t j_dev_mode;
 
     /* first block on s_dev of reserved area journal */
     int j_1st_reserved_block;
 
     unsigned long j_state;
     unsigned int j_trans_id;
     unsigned long j_mount_id;
 
     /* start of current waiting commit (index into j_ap_blocks) */
     unsigned long j_start;
     unsigned long j_len;    /* length of current waiting commit */
 
     /* number of buffers requested by journal_begin() */
     unsigned long j_len_alloc;
 
     atomic_t j_wcount;  /* count of writers for current commit */
 
     /* batch count. allows turning X transactions into 1 */
     unsigned long j_bcount;
 
     /* first unflushed transactions offset */
     unsigned long j_first_unflushed_offset;
 
     /* last fully flushed journal timestamp */
     unsigned j_last_flush_trans_id;
 
     struct buffer_head *j_header_bh;
 
     time64_t j_trans_start_time;    /* time this transaction started */
     struct mutex j_mutex;
     struct mutex j_flush_mutex;
 
     /* wait for current transaction to finish before starting new one */
     wait_queue_head_t j_join_wait;
 
     atomic_t j_jlock;       /* lock for j_join_wait */
     int j_list_bitmap_index;    /* number of next list bitmap to use */
 
     /* no more journal begins allowed. MUST sleep on j_join_wait */
     int j_must_wait;
 
     /* next journal_end will flush all journal list */
     int j_next_full_flush;
 
     /* next journal_end will flush all async commits */
     int j_next_async_flush;
 
     int j_cnode_used;   /* number of cnodes on the used list */
     int j_cnode_free;   /* number of cnodes on the free list */
 
     /* max number of blocks in a transaction.  */
     unsigned int j_trans_max;
 
     /* max number of blocks to batch into a trans */
     unsigned int j_max_batch;
 
     /* in seconds, how old can an async commit be */
     unsigned int j_max_commit_age;
 
     /* in seconds, how old can a transaction be */
     unsigned int j_max_trans_age;
 
     /* the default for the max commit age */
     unsigned int j_default_max_commit_age;
 
     struct reiserfs_journal_cnode *j_cnode_free_list;
 
     /* orig pointer returned from vmalloc */
     struct reiserfs_journal_cnode *j_cnode_free_orig;
 
     struct reiserfs_journal_list *j_current_jl;
     int j_free_bitmap_nodes;
     int j_used_bitmap_nodes;
 
     int j_num_lists;    /* total number of active transactions */
     int j_num_work_lists;   /* number that need attention from kreiserfsd */
 
     /* debugging to make sure things are flushed in order */
     unsigned int j_last_flush_id;
 
     /* debugging to make sure things are committed in order */
     unsigned int j_last_commit_id;
 
     struct list_head j_bitmap_nodes;
     struct list_head j_dirty_buffers;
     spinlock_t j_dirty_buffers_lock;    /* protects j_dirty_buffers */
 
     /* list of all active transactions */
     struct list_head j_journal_list;
 
     /* lists that haven't been touched by writeback attempts */
     struct list_head j_working_list;
 
     /* hash table for real buffer heads in current trans */
     struct reiserfs_journal_cnode *j_hash_table[JOURNAL_HASH_SIZE];
 
     /* hash table for all the real buffer heads in all the transactions */
     struct reiserfs_journal_cnode *j_list_hash_table[JOURNAL_HASH_SIZE];
 
     /* array of bitmaps to record the deleted blocks */
     struct reiserfs_list_bitmap j_list_bitmap[JOURNAL_NUM_BITMAPS];
 
     /* list of inodes which have preallocated blocks */
     struct list_head j_prealloc_list;
     int j_persistent_trans;
     unsigned long j_max_trans_size;
     unsigned long j_max_batch_size;
 
     int j_errno;
 
     /* when flushing ordered buffers, throttle new ordered writers */
     struct delayed_work j_work;
     struct super_block *j_work_sb;
     atomic_t j_async_throttle;
 };
 
 enum journal_state_bits {
     J_WRITERS_BLOCKED = 1,  /* set when new writers not allowed */
     J_WRITERS_QUEUED,    /* set when log is full due to too many writers */
     J_ABORTED,           /* set when log is aborted */
 };
 
 /* ick.  magic string to find desc blocks in the journal */
 #define JOURNAL_DESC_MAGIC "ReIsErLB"
 
 typedef __u32(*hashf_t) (const signed char *, int);
 
 struct reiserfs_bitmap_info {
     __u32 free_count;
 };
 
 struct proc_dir_entry;
 
 #if defined( CONFIG_PROC_FS ) && defined( CONFIG_REISERFS_PROC_INFO )
 typedef unsigned long int stat_cnt_t;
 typedef struct reiserfs_proc_info_data {
     spinlock_t lock;
     int exiting;
     int max_hash_collisions;
 
     stat_cnt_t breads;
     stat_cnt_t bread_miss;
     stat_cnt_t search_by_key;
     stat_cnt_t search_by_key_fs_changed;
     stat_cnt_t search_by_key_restarted;
 
     stat_cnt_t insert_item_restarted;
     stat_cnt_t paste_into_item_restarted;
     stat_cnt_t cut_from_item_restarted;
     stat_cnt_t delete_solid_item_restarted;
     stat_cnt_t delete_item_restarted;
 
     stat_cnt_t leaked_oid;
     stat_cnt_t leaves_removable;
 
     /*
      * balances per level.
      * Use explicit 5 as MAX_HEIGHT is not visible yet.
      */
     stat_cnt_t balance_at[5];   /* XXX */
     /* sbk == search_by_key */
     stat_cnt_t sbk_read_at[5];  /* XXX */
     stat_cnt_t sbk_fs_changed[5];
     stat_cnt_t sbk_restarted[5];
     stat_cnt_t items_at[5]; /* XXX */
     stat_cnt_t free_at[5];  /* XXX */
     stat_cnt_t can_node_be_removed[5];  /* XXX */
     long int lnum[5];   /* XXX */
     long int rnum[5];   /* XXX */
     long int lbytes[5]; /* XXX */
     long int rbytes[5]; /* XXX */
     stat_cnt_t get_neighbors[5];
     stat_cnt_t get_neighbors_restart[5];
     stat_cnt_t need_l_neighbor[5];
     stat_cnt_t need_r_neighbor[5];
 
     stat_cnt_t free_block;
     struct __scan_bitmap_stats {
         stat_cnt_t call;
         stat_cnt_t wait;
         stat_cnt_t bmap;
         stat_cnt_t retry;
         stat_cnt_t in_journal_hint;
         stat_cnt_t in_journal_nohint;
         stat_cnt_t stolen;
     } scan_bitmap;
     struct __journal_stats {
         stat_cnt_t in_journal;
         stat_cnt_t in_journal_bitmap;
         stat_cnt_t in_journal_reusable;
         stat_cnt_t lock_journal;
         stat_cnt_t lock_journal_wait;
         stat_cnt_t journal_being;
         stat_cnt_t journal_relock_writers;
         stat_cnt_t journal_relock_wcount;
         stat_cnt_t mark_dirty;
         stat_cnt_t mark_dirty_already;
         stat_cnt_t mark_dirty_notjournal;
         stat_cnt_t restore_prepared;
         stat_cnt_t prepare;
         stat_cnt_t prepare_retry;
     } journal;
 } reiserfs_proc_info_data_t;
 #else
 typedef struct reiserfs_proc_info_data {
 } reiserfs_proc_info_data_t;
 #endif
 
 /* Number of quota types we support */
 #define REISERFS_MAXQUOTAS 2
 
 /* reiserfs union of in-core super block data */
 struct reiserfs_sb_info {
     /* Buffer containing the super block */
     struct buffer_head *s_sbh;
 
     /* Pointer to the on-disk super block in the buffer */
     struct reiserfs_super_block *s_rs;
     struct reiserfs_bitmap_info *s_ap_bitmap;
 
     /* pointer to journal information */
     struct reiserfs_journal *s_journal;
 
     unsigned short s_mount_state;   /* reiserfs state (valid, invalid) */
 
     /* Serialize writers access, replace the old bkl */
     struct mutex lock;
 
     /* Owner of the lock (can be recursive) */
     struct task_struct *lock_owner;
 
     /* Depth of the lock, start from -1 like the bkl */
     int lock_depth;
 
     struct workqueue_struct *commit_wq;
 
     /* Comment? -Hans */
     void (*end_io_handler) (struct buffer_head *, int);
 
     /*
      * pointer to function which is used to sort names in directory.
      * Set on mount
      */
     hashf_t s_hash_function;
 
     /* reiserfs's mount options are set here */
     unsigned long s_mount_opt;
 
     /* This is a structure that describes block allocator options */
     struct {
         /* Bitfield for enable/disable kind of options */
         unsigned long bits;
 
         /*
          * size started from which we consider file
          * to be a large one (in blocks)
          */
         unsigned long large_file_size;
 
         int border; /* percentage of disk, border takes */
 
         /*
          * Minimal file size (in blocks) starting
          * from which we do preallocations
          */
         int preallocmin;
 
         /*
          * Number of blocks we try to prealloc when file
          * reaches preallocmin size (in blocks) or prealloc_list
          is empty.
          */
         int preallocsize;
     } s_alloc_options;
 
     /* Comment? -Hans */
     wait_queue_head_t s_wait;
     /* increased by one every time the  tree gets re-balanced */
     atomic_t s_generation_counter;
 
     /* File system properties. Currently holds on-disk FS format */
     unsigned long s_properties;
 
     /* session statistics */
     int s_disk_reads;
     int s_disk_writes;
     int s_fix_nodes;
     int s_do_balance;
     int s_unneeded_left_neighbor;
     int s_good_search_by_key_reada;
     int s_bmaps;
     int s_bmaps_without_search;
     int s_direct2indirect;
     int s_indirect2direct;
 
     /*
      * set up when it's ok for reiserfs_read_inode2() to read from
      * disk inode with nlink==0. Currently this is only used during
      * finish_unfinished() processing at mount time
      */
     int s_is_unlinked_ok;
 
     reiserfs_proc_info_data_t s_proc_info_data;
     struct proc_dir_entry *procdir;
 
     /* amount of blocks reserved for further allocations */
     int reserved_blocks;
 
 
     /* this lock on now only used to protect reserved_blocks variable */
     spinlock_t bitmap_lock;
     struct dentry *priv_root;   /* root of /.reiserfs_priv */
     struct dentry *xattr_root;  /* root of /.reiserfs_priv/xattrs */
     int j_errno;
 
     int work_queued;              /* non-zero delayed work is queued */
     struct delayed_work old_work; /* old transactions flush delayed work */
     spinlock_t old_work_lock;     /* protects old_work and work_queued */
 
 #ifdef CONFIG_QUOTA
     char *s_qf_names[REISERFS_MAXQUOTAS];
     int s_jquota_fmt;
 #endif
     char *s_jdev;       /* Stored jdev for mount option showing */
 #ifdef CONFIG_REISERFS_CHECK
 
     /*
      * Detects whether more than one copy of tb exists per superblock
      * as a means of checking whether do_balance is executing
      * concurrently against another tree reader/writer on a same
      * mount point.
      */
     struct tree_balance *cur_tb;
 #endif
 };
 
 /* Definitions of reiserfs on-disk properties: */
 #define REISERFS_3_5 0
 #define REISERFS_3_6 1
 #define REISERFS_OLD_FORMAT 2
 
 /* Mount options */
 enum reiserfs_mount_options {
     /* large tails will be created in a session */
     REISERFS_LARGETAIL,
     /*
      * small (for files less than block size) tails will
      * be created in a session
      */
     REISERFS_SMALLTAIL,
 
     /* replay journal and return 0. Use by fsck */
     REPLAYONLY,
 
     /*
      * -o conv: causes conversion of old format super block to the
      * new format. If not specified - old partition will be dealt
      * with in a manner of 3.5.x
      */
     REISERFS_CONVERT,
 
     /*
      * -o hash={tea, rupasov, r5, detect} is meant for properly mounting
      * reiserfs disks from 3.5.19 or earlier.  99% of the time, this
      * option is not required.  If the normal autodection code can't
      * determine which hash to use (because both hashes had the same
      * value for a file) use this option to force a specific hash.
      * It won't allow you to override the existing hash on the FS, so
      * if you have a tea hash disk, and mount with -o hash=rupasov,
      * the mount will fail.
      */
     FORCE_TEA_HASH,     /* try to force tea hash on mount */
     FORCE_RUPASOV_HASH, /* try to force rupasov hash on mount */
     FORCE_R5_HASH,      /* try to force rupasov hash on mount */
     FORCE_HASH_DETECT,  /* try to detect hash function on mount */
 
     REISERFS_DATA_LOG,
     REISERFS_DATA_ORDERED,
     REISERFS_DATA_WRITEBACK,
 
     /*
      * used for testing experimental features, makes benchmarking new
      * features with and without more convenient, should never be used by
      * users in any code shipped to users (ideally)
      */
 
     REISERFS_NO_BORDER,
     REISERFS_NO_UNHASHED_RELOCATION,
     REISERFS_HASHED_RELOCATION,
     REISERFS_ATTRS,
     REISERFS_XATTRS_USER,
     REISERFS_POSIXACL,
     REISERFS_EXPOSE_PRIVROOT,
     REISERFS_BARRIER_NONE,
     REISERFS_BARRIER_FLUSH,
 
     /* Actions on error */
     REISERFS_ERROR_PANIC,
     REISERFS_ERROR_RO,
     REISERFS_ERROR_CONTINUE,
 
     REISERFS_USRQUOTA,  /* User quota option specified */
     REISERFS_GRPQUOTA,  /* Group quota option specified */
 
     REISERFS_TEST1,
     REISERFS_TEST2,
     REISERFS_TEST3,
     REISERFS_TEST4,
     REISERFS_UNSUPPORTED_OPT,
 };
 
 #define reiserfs_r5_hash(s) (REISERFS_SB(s)->s_mount_opt & (1 << FORCE_R5_HASH))
 #define reiserfs_rupasov_hash(s) (REISERFS_SB(s)->s_mount_opt & (1 << FORCE_RUPASOV_HASH))
 #define reiserfs_tea_hash(s) (REISERFS_SB(s)->s_mount_opt & (1 << FORCE_TEA_HASH))
 #define reiserfs_hash_detect(s) (REISERFS_SB(s)->s_mount_opt & (1 << FORCE_HASH_DETECT))
 #define reiserfs_no_border(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_NO_BORDER))
 #define reiserfs_no_unhashed_relocation(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_NO_UNHASHED_RELOCATION))
 #define reiserfs_hashed_relocation(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_HASHED_RELOCATION))
 #define reiserfs_test4(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_TEST4))
 
 #define have_large_tails(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_LARGETAIL))
 #define have_small_tails(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_SMALLTAIL))
 #define replay_only(s) (REISERFS_SB(s)->s_mount_opt & (1 << REPLAYONLY))
 #define reiserfs_attrs(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_ATTRS))
 #define old_format_only(s) (REISERFS_SB(s)->s_properties & (1 << REISERFS_3_5))
 #define convert_reiserfs(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_CONVERT))
 #define reiserfs_data_log(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_DATA_LOG))
 #define reiserfs_data_ordered(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_DATA_ORDERED))
 #define reiserfs_data_writeback(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_DATA_WRITEBACK))
 #define reiserfs_xattrs_user(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_XATTRS_USER))
 #define reiserfs_posixacl(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_POSIXACL))
 #define reiserfs_expose_privroot(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_EXPOSE_PRIVROOT))
 #define reiserfs_xattrs_optional(s) (reiserfs_xattrs_user(s) || reiserfs_posixacl(s))
 #define reiserfs_barrier_none(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_BARRIER_NONE))
 #define reiserfs_barrier_flush(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_BARRIER_FLUSH))
 
 #define reiserfs_error_panic(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_ERROR_PANIC))
 #define reiserfs_error_ro(s) (REISERFS_SB(s)->s_mount_opt & (1 << REISERFS_ERROR_RO))
 
 void reiserfs_file_buffer(struct buffer_head *bh, int list);
 extern struct file_system_type reiserfs_fs_type;
 int reiserfs_resize(struct super_block *, unsigned long);
 
 #define CARRY_ON                0
 #define SCHEDULE_OCCURRED       1
 
 #define SB_BUFFER_WITH_SB(s) (REISERFS_SB(s)->s_sbh)
 #define SB_JOURNAL(s) (REISERFS_SB(s)->s_journal)
 #define SB_JOURNAL_1st_RESERVED_BLOCK(s) (SB_JOURNAL(s)->j_1st_reserved_block)
 #define SB_JOURNAL_LEN_FREE(s) (SB_JOURNAL(s)->j_journal_len_free)
 #define SB_AP_BITMAP(s) (REISERFS_SB(s)->s_ap_bitmap)
 
 #define SB_DISK_JOURNAL_HEAD(s) (SB_JOURNAL(s)->j_header_bh->)
 
 #define reiserfs_is_journal_aborted(journal) (unlikely (__reiserfs_is_journal_aborted (journal)))
 static inline int __reiserfs_is_journal_aborted(struct reiserfs_journal
                         *journal)
 {
     return test_bit(J_ABORTED, &journal->j_state);
 }
 
 /*
  * Locking primitives. The write lock is a per superblock
  * special mutex that has properties close to the Big Kernel Lock
  * which was used in the previous locking scheme.
  */
 void reiserfs_write_lock(struct super_block *s);
 void reiserfs_write_unlock(struct super_block *s);
 int __must_check reiserfs_write_unlock_nested(struct super_block *s);
 void reiserfs_write_lock_nested(struct super_block *s, int depth);
 
 #ifdef CONFIG_REISERFS_CHECK
 void reiserfs_lock_check_recursive(struct super_block *s);
 #else
 static inline void reiserfs_lock_check_recursive(struct super_block *s) { }
 #endif
 
 /*
  * Several mutexes depend on the write lock.
  * However sometimes we want to relax the write lock while we hold
  * these mutexes, according to the release/reacquire on schedule()
  * properties of the Bkl that were used.
  * Reiserfs performances and locking were based on this scheme.
  * Now that the write lock is a mutex and not the bkl anymore, doing so
  * may result in a deadlock:
  *
  * A acquire write_lock
  * A acquire j_commit_mutex
  * A release write_lock and wait for something
  * B acquire write_lock
  * B can't acquire j_commit_mutex and sleep
  * A can't acquire write lock anymore
  * deadlock
  *
  * What we do here is avoiding such deadlock by playing the same game
  * than the Bkl: if we can't acquire a mutex that depends on the write lock,
  * we release the write lock, wait a bit and then retry.
  *
  * The mutexes concerned by this hack are:
  * - The commit mutex of a journal list
  * - The flush mutex
  * - The journal lock
  * - The inode mutex
  */
 static inline void reiserfs_mutex_lock_safe(struct mutex *m,
                         struct super_block *s)
 {
     int depth;
 
     depth = reiserfs_write_unlock_nested(s);
     mutex_lock(m);
     reiserfs_write_lock_nested(s, depth);
 }
 
 static inline void
 reiserfs_mutex_lock_nested_safe(struct mutex *m, unsigned int subclass,
                 struct super_block *s)
 {
     int depth;
 
     depth = reiserfs_write_unlock_nested(s);
     mutex_lock_nested(m, subclass);
     reiserfs_write_lock_nested(s, depth);
 }
 
 static inline void
 reiserfs_down_read_safe(struct rw_semaphore *sem, struct super_block *s)
 {
        int depth;
        depth = reiserfs_write_unlock_nested(s);
        down_read(sem);
        reiserfs_write_lock_nested(s, depth);
 }
 
 /*
  * When we schedule, we usually want to also release the write lock,
  * according to the previous bkl based locking scheme of reiserfs.
  */
 static inline void reiserfs_cond_resched(struct super_block *s)
 {
     if (need_resched()) {
         int depth;
 
         depth = reiserfs_write_unlock_nested(s);
         schedule();
         reiserfs_write_lock_nested(s, depth);
     }
 }
 
 struct fid;
 
 /*
  * in reading the #defines, it may help to understand that they employ
  *  the following abbreviations:
  *
  *  B = Buffer
  *  I = Item header
  *  H = Height within the tree (should be changed to LEV)
  *  N = Number of the item in the node
  *  STAT = stat data
  *  DEH = Directory Entry Header
  *  EC = Entry Count
  *  E = Entry number
  *  UL = Unsigned Long
  *  BLKH = BLocK Header
  *  UNFM = UNForMatted node
  *  DC = Disk Child
  *  P = Path
  *
  *  These #defines are named by concatenating these abbreviations,
  *  where first comes the arguments, and last comes the return value,
  *  of the macro.
  */
 
 #define USE_INODE_GENERATION_COUNTER
 
 #define REISERFS_PREALLOCATE
 #define DISPLACE_NEW_PACKING_LOCALITIES
 #define PREALLOCATION_SIZE 9
 
 /* n must be power of 2 */
 #define _ROUND_UP(x,n) (((x)+(n)-1u) & ~((n)-1u))
 
 /*
  * to be ok for alpha and others we have to align structures to 8 byte
  * boundary.
  * FIXME: do not change 4 by anything else: there is code which relies on that
  */
 #define ROUND_UP(x) _ROUND_UP(x,8LL)
 
 /*
  * debug levels.  Right now, CONFIG_REISERFS_CHECK means print all debug
  * messages.
  */
 #define REISERFS_DEBUG_CODE 5   /* extra messages to help find/debug errors */
 
 void __reiserfs_warning(struct super_block *s, const char *id,
              const char *func, const char *fmt, ...);
 #define reiserfs_warning(s, id, fmt, args...) \
      __reiserfs_warning(s, id, __func__, fmt, ##args)
 /* assertions handling */
 
 /* always check a condition and panic if it's false. */
 #define __RASSERT(cond, scond, format, args...)         \
 do {                                    \
     if (!(cond))                            \
         reiserfs_panic(NULL, "assertion failure", "(" #cond ") at " \
                    __FILE__ ":%i:%s: " format "\n",     \
                    __LINE__, __func__ , ##args);        \
 } while (0)
 
 #define RASSERT(cond, format, args...) __RASSERT(cond, #cond, format, ##args)
 
 #if defined( CONFIG_REISERFS_CHECK )
 #define RFALSE(cond, format, args...) __RASSERT(!(cond), "!(" #cond ")", format, ##args)
 #else
 #define RFALSE( cond, format, args... ) do {;} while( 0 )
 #endif
 
 #define CONSTF __attribute_const__
 /*
  * Disk Data Structures
  */
 
 /***************************************************************************
  *                             SUPER BLOCK                                 *
  ***************************************************************************/
 
 /*
  * Structure of super block on disk, a version of which in RAM is often
  * accessed as REISERFS_SB(s)->s_rs. The version in RAM is part of a larger
  * structure containing fields never written to disk.
  */
 #define UNSET_HASH 0    /* Detect hash on disk */
 #define TEA_HASH  1
 #define YURA_HASH 2
 #define R5_HASH   3
 #define DEFAULT_HASH R5_HASH
 
 struct journal_params {
     /* where does journal start from on its * device */
     __le32 jp_journal_1st_block;
 
     /* journal device st_rdev */
     __le32 jp_journal_dev;
 
     /* size of the journal */
     __le32 jp_journal_size;
 
     /* max number of blocks in a transaction. */
     __le32 jp_journal_trans_max;
 
     /*
      * random value made on fs creation
      * (this was sb_journal_block_count)
      */
     __le32 jp_journal_magic;
 
     /* max number of blocks to batch into a trans */
     __le32 jp_journal_max_batch;
 
     /* in seconds, how old can an async  commit be */
     __le32 jp_journal_max_commit_age;
 
     /* in seconds, how old can a transaction be */
     __le32 jp_journal_max_trans_age;
 };
 
 /* this is the super from 3.5.X, where X >= 10 */
 struct reiserfs_super_block_v1 {
     __le32 s_block_count;   /* blocks count         */
     __le32 s_free_blocks;   /* free blocks count    */
     __le32 s_root_block;    /* root block number    */
     struct journal_params s_journal;
     __le16 s_blocksize; /* block size */
 
     /* max size of object id array, see get_objectid() commentary  */
     __le16 s_oid_maxsize;
     __le16 s_oid_cursize;   /* current size of object id array */
 
     /* this is set to 1 when filesystem was umounted, to 2 - when not */
     __le16 s_umount_state;
 
     /*
      * reiserfs magic string indicates that file system is reiserfs:
      * "ReIsErFs" or "ReIsEr2Fs" or "ReIsEr3Fs"
      */
     char s_magic[10];
 
     /*
      * it is set to used by fsck to mark which
      * phase of rebuilding is done
      */
     __le16 s_fs_state;
     /*
      * indicate, what hash function is being use
      * to sort names in a directory
      */
     __le32 s_hash_function_code;
     __le16 s_tree_height;   /* height of disk tree */
 
     /*
      * amount of bitmap blocks needed to address
      * each block of file system
      */
     __le16 s_bmap_nr;
 
     /*
      * this field is only reliable on filesystem with non-standard journal
      */
     __le16 s_version;
 
     /*
      * size in blocks of journal area on main device, we need to
      * keep after making fs with non-standard journal
      */
     __le16 s_reserved_for_journal;
 } __attribute__ ((__packed__));
 
 #define SB_SIZE_V1 (sizeof(struct reiserfs_super_block_v1))
 
 /* this is the on disk super block */
 struct reiserfs_super_block {
     struct reiserfs_super_block_v1 s_v1;
     __le32 s_inode_generation;
 
     /* Right now used only by inode-attributes, if enabled */
     __le32 s_flags;
 
     unsigned char s_uuid[16];   /* filesystem unique identifier */
     unsigned char s_label[16];  /* filesystem volume label */
     __le16 s_mnt_count;     /* Count of mounts since last fsck */
     __le16 s_max_mnt_count;     /* Maximum mounts before check */
     __le32 s_lastcheck;     /* Timestamp of last fsck */
     __le32 s_check_interval;    /* Interval between checks */
 
     /*
      * zero filled by mkreiserfs and reiserfs_convert_objectid_map_v1()
      * so any additions must be updated there as well. */
     char s_unused[76];
 } __attribute__ ((__packed__));
 
 #define SB_SIZE (sizeof(struct reiserfs_super_block))
 
 #define REISERFS_VERSION_1 0
 #define REISERFS_VERSION_2 2
 
 /* on-disk super block fields converted to cpu form */
 #define SB_DISK_SUPER_BLOCK(s) (REISERFS_SB(s)->s_rs)
 #define SB_V1_DISK_SUPER_BLOCK(s) (&(SB_DISK_SUPER_BLOCK(s)->s_v1))
 #define SB_BLOCKSIZE(s) \
         le32_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_blocksize))
 #define SB_BLOCK_COUNT(s) \
         le32_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_block_count))
 #define SB_FREE_BLOCKS(s) \
         le32_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_free_blocks))
 #define SB_REISERFS_MAGIC(s) \
         (SB_V1_DISK_SUPER_BLOCK(s)->s_magic)
 #define SB_ROOT_BLOCK(s) \
         le32_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_root_block))
 #define SB_TREE_HEIGHT(s) \
         le16_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_tree_height))
 #define SB_REISERFS_STATE(s) \
         le16_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_umount_state))
 #define SB_VERSION(s) le16_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_version))
 #define SB_BMAP_NR(s) le16_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_bmap_nr))
 
 #define PUT_SB_BLOCK_COUNT(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_block_count = cpu_to_le32(val); } while (0)
 #define PUT_SB_FREE_BLOCKS(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_free_blocks = cpu_to_le32(val); } while (0)
 #define PUT_SB_ROOT_BLOCK(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_root_block = cpu_to_le32(val); } while (0)
 #define PUT_SB_TREE_HEIGHT(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_tree_height = cpu_to_le16(val); } while (0)
 #define PUT_SB_REISERFS_STATE(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_umount_state = cpu_to_le16(val); } while (0)
 #define PUT_SB_VERSION(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_version = cpu_to_le16(val); } while (0)
 #define PUT_SB_BMAP_NR(s, val) \
    do { SB_V1_DISK_SUPER_BLOCK(s)->s_bmap_nr = cpu_to_le16 (val); } while (0)
 
 #define SB_ONDISK_JP(s) (&SB_V1_DISK_SUPER_BLOCK(s)->s_journal)
 #define SB_ONDISK_JOURNAL_SIZE(s) \
          le32_to_cpu ((SB_ONDISK_JP(s)->jp_journal_size))
 #define SB_ONDISK_JOURNAL_1st_BLOCK(s) \
          le32_to_cpu ((SB_ONDISK_JP(s)->jp_journal_1st_block))
 #define SB_ONDISK_JOURNAL_DEVICE(s) \
          le32_to_cpu ((SB_ONDISK_JP(s)->jp_journal_dev))
 #define SB_ONDISK_RESERVED_FOR_JOURNAL(s) \
          le16_to_cpu ((SB_V1_DISK_SUPER_BLOCK(s)->s_reserved_for_journal))
 
 #define is_block_in_log_or_reserved_area(s, block) \
          block >= SB_JOURNAL_1st_RESERVED_BLOCK(s) \
          && block < SB_JOURNAL_1st_RESERVED_BLOCK(s) +  \
          ((!is_reiserfs_jr(SB_DISK_SUPER_BLOCK(s)) ? \
          SB_ONDISK_JOURNAL_SIZE(s) + 1 : SB_ONDISK_RESERVED_FOR_JOURNAL(s)))
 
 int is_reiserfs_3_5(struct reiserfs_super_block *rs);
 int is_reiserfs_3_6(struct reiserfs_super_block *rs);
 int is_reiserfs_jr(struct reiserfs_super_block *rs);
 
 /*
  * ReiserFS leaves the first 64k unused, so that partition labels have
  * enough space.  If someone wants to write a fancy bootloader that
  * needs more than 64k, let us know, and this will be increased in size.
  * This number must be larger than the largest block size on any
  * platform, or code will break.  -Hans
  */
 #define REISERFS_DISK_OFFSET_IN_BYTES (64 * 1024)
 #define REISERFS_FIRST_BLOCK unused_define
 #define REISERFS_JOURNAL_OFFSET_IN_BYTES REISERFS_DISK_OFFSET_IN_BYTES
 
 /* the spot for the super in versions 3.5 - 3.5.10 (inclusive) */
 #define REISERFS_OLD_DISK_OFFSET_IN_BYTES (8 * 1024)
 
 /* reiserfs internal error code (used by search_by_key and fix_nodes)) */
 #define CARRY_ON      0
 #define REPEAT_SEARCH -1
 #define IO_ERROR      -2
 #define NO_DISK_SPACE -3
 #define NO_BALANCING_NEEDED  (-4)
 #define NO_MORE_UNUSED_CONTIGUOUS_BLOCKS (-5)
 #define QUOTA_EXCEEDED -6
 
 typedef __u32 b_blocknr_t;
 typedef __le32 unp_t;
 
 struct unfm_nodeinfo {
     unp_t unfm_nodenum;
     unsigned short unfm_freespace;
 };
 
 /* there are two formats of keys: 3.5 and 3.6 */
 #define KEY_FORMAT_3_5 0
 #define KEY_FORMAT_3_6 1
 
 /* there are two stat datas */
 #define STAT_DATA_V1 0
 #define STAT_DATA_V2 1
 
 static inline struct reiserfs_inode_info *REISERFS_I(const struct inode *inode)
 {
     return container_of(inode, struct reiserfs_inode_info, vfs_inode);
 }
 
 static inline struct reiserfs_sb_info *REISERFS_SB(const struct super_block *sb)
 {
     return sb->s_fs_info;
 }
 
 /*
  * Don't trust REISERFS_SB(sb)->s_bmap_nr, it's a u16
  * which overflows on large file systems.
  */
 static inline __u32 reiserfs_bmap_count(struct super_block *sb)
 {
     return (SB_BLOCK_COUNT(sb) - 1) / (sb->s_blocksize * 8) + 1;
 }
 
 static inline int bmap_would_wrap(unsigned bmap_nr)
 {
     return bmap_nr > ((1LL << 16) - 1);
 }
 
 extern const struct xattr_handler *reiserfs_xattr_handlers[];
 
 /*
  * this says about version of key of all items (but stat data) the
  * object consists of
  */
 #define get_inode_item_key_version( inode )                                    \
     ((REISERFS_I(inode)->i_flags & i_item_key_version_mask) ? KEY_FORMAT_3_6 : KEY_FORMAT_3_5)
 
 #define set_inode_item_key_version( inode, version )                           \
          ({ if((version)==KEY_FORMAT_3_6)                                      \
                 REISERFS_I(inode)->i_flags |= i_item_key_version_mask;      \
             else                                                               \
                 REISERFS_I(inode)->i_flags &= ~i_item_key_version_mask; })
 
 #define get_inode_sd_version(inode)                                            \
     ((REISERFS_I(inode)->i_flags & i_stat_data_version_mask) ? STAT_DATA_V2 : STAT_DATA_V1)
 
 #define set_inode_sd_version(inode, version)                                   \
          ({ if((version)==STAT_DATA_V2)                                        \
                 REISERFS_I(inode)->i_flags |= i_stat_data_version_mask;     \
             else                                                               \
                 REISERFS_I(inode)->i_flags &= ~i_stat_data_version_mask; })
 
 /*
  * This is an aggressive tail suppression policy, I am hoping it
  * improves our benchmarks. The principle behind it is that percentage
  * space saving is what matters, not absolute space saving.  This is
  * non-intuitive, but it helps to understand it if you consider that the
  * cost to access 4 blocks is not much more than the cost to access 1
  * block, if you have to do a seek and rotate.  A tail risks a
  * non-linear disk access that is significant as a percentage of total
  * time cost for a 4 block file and saves an amount of space that is
  * less significant as a percentage of space, or so goes the hypothesis.
  * -Hans
  */
 #define STORE_TAIL_IN_UNFM_S1(n_file_size,n_tail_size,n_block_size) \
 (\
   (!(n_tail_size)) || \
   (((n_tail_size) > MAX_DIRECT_ITEM_LEN(n_block_size)) || \
    ( (n_file_size) >= (n_block_size) * 4 ) || \
    ( ( (n_file_size) >= (n_block_size) * 3 ) && \
      ( (n_tail_size) >=   (MAX_DIRECT_ITEM_LEN(n_block_size))/4) ) || \
    ( ( (n_file_size) >= (n_block_size) * 2 ) && \
      ( (n_tail_size) >=   (MAX_DIRECT_ITEM_LEN(n_block_size))/2) ) || \
    ( ( (n_file_size) >= (n_block_size) ) && \
      ( (n_tail_size) >=   (MAX_DIRECT_ITEM_LEN(n_block_size) * 3)/4) ) ) \
 )
 
 /*
  * Another strategy for tails, this one means only create a tail if all the
  * file would fit into one DIRECT item.
  * Primary intention for this one is to increase performance by decreasing
  * seeking.
 */
 #define STORE_TAIL_IN_UNFM_S2(n_file_size,n_tail_size,n_block_size) \
 (\
   (!(n_tail_size)) || \
   (((n_file_size) > MAX_DIRECT_ITEM_LEN(n_block_size)) ) \
 )
 
 /*
  * values for s_umount_state field
  */
 #define REISERFS_VALID_FS    1
 #define REISERFS_ERROR_FS    2
 
 /*
  * there are 5 item types currently
  */
 #define TYPE_STAT_DATA 0
 #define TYPE_INDIRECT 1
 #define TYPE_DIRECT 2
 #define TYPE_DIRENTRY 3
 #define TYPE_MAXTYPE 3
 #define TYPE_ANY 15     /* FIXME: comment is required */
 
 /***************************************************************************
  *                       KEY & ITEM HEAD                                   *
  ***************************************************************************/
 
 /* * directories use this key as well as old files */
 struct offset_v1 {
     __le32 k_offset;
     __le32 k_uniqueness;
 } __attribute__ ((__packed__));
 
 struct offset_v2 {
     __le64 v;
 } __attribute__ ((__packed__));
 
 static inline __u16 offset_v2_k_type(const struct offset_v2 *v2)
 {
     __u8 type = le64_to_cpu(v2->v) >> 60;
     return (type <= TYPE_MAXTYPE) ? type : TYPE_ANY;
 }
 
 static inline void set_offset_v2_k_type(struct offset_v2 *v2, int type)
 {
     v2->v =
         (v2->v & cpu_to_le64(~0ULL >> 4)) | cpu_to_le64((__u64) type << 60);
 }
 
 static inline loff_t offset_v2_k_offset(const struct offset_v2 *v2)
 {
     return le64_to_cpu(v2->v) & (~0ULL >> 4);
 }
 
 static inline void set_offset_v2_k_offset(struct offset_v2 *v2, loff_t offset)
 {
     offset &= (~0ULL >> 4);
     v2->v = (v2->v & cpu_to_le64(15ULL << 60)) | cpu_to_le64(offset);
 }
 
 /*
  * Key of an item determines its location in the S+tree, and
  * is composed of 4 components
  */
 struct reiserfs_key {
     /* packing locality: by default parent directory object id */
     __le32 k_dir_id;
 
     __le32 k_objectid;  /* object identifier */
     union {
         struct offset_v1 k_offset_v1;
         struct offset_v2 k_offset_v2;
     } __attribute__ ((__packed__)) u;
 } __attribute__ ((__packed__));
 
 struct in_core_key {
     /* packing locality: by default parent directory object id */
     __u32 k_dir_id;
     __u32 k_objectid;   /* object identifier */
     __u64 k_offset;
     __u8 k_type;
 };
 
 struct cpu_key {
     struct in_core_key on_disk_key;
     int version;
     /* 3 in all cases but direct2indirect and indirect2direct conversion */
     int key_length;
 };
 
 /*
  * Our function for comparing keys can compare keys of different
  * lengths.  It takes as a parameter the length of the keys it is to
  * compare.  These defines are used in determining what is to be passed
  * to it as that parameter.
  */
 #define REISERFS_FULL_KEY_LEN     4
 #define REISERFS_SHORT_KEY_LEN    2
 
 /* The result of the key compare */
 #define FIRST_GREATER 1
 #define SECOND_GREATER -1
 #define KEYS_IDENTICAL 0
 #define KEY_FOUND 1
 #define KEY_NOT_FOUND 0
 
 #define KEY_SIZE (sizeof(struct reiserfs_key))
 
 /* return values for search_by_key and clones */
 #define ITEM_FOUND 1
 #define ITEM_NOT_FOUND 0
 #define ENTRY_FOUND 1
 #define ENTRY_NOT_FOUND 0
 #define DIRECTORY_NOT_FOUND -1
 #define REGULAR_FILE_FOUND -2
 #define DIRECTORY_FOUND -3
 #define BYTE_FOUND 1
 #define BYTE_NOT_FOUND 0
 #define FILE_NOT_FOUND -1
 
 #define POSITION_FOUND 1
 #define POSITION_NOT_FOUND 0
 
 /* return values for reiserfs_find_entry and search_by_entry_key */
 #define NAME_FOUND 1
 #define NAME_NOT_FOUND 0
 #define GOTO_PREVIOUS_ITEM 2
 #define NAME_FOUND_INVISIBLE 3
 
 /*
  * Everything in the filesystem is stored as a set of items.  The
  * item head contains the key of the item, its free space (for
  * indirect items) and specifies the location of the item itself
  * within the block.
  */
 
 struct item_head {
     /*
      * Everything in the tree is found by searching for it based on
      * its key.
      */
     struct reiserfs_key ih_key;
     union {
         /*
          * The free space in the last unformatted node of an
          * indirect item if this is an indirect item.  This
          * equals 0xFFFF iff this is a direct item or stat data
          * item. Note that the key, not this field, is used to
          * determine the item type, and thus which field this
          * union contains.
          */
         __le16 ih_free_space_reserved;
 
         /*
          * Iff this is a directory item, this field equals the
          * number of directory entries in the directory item.
          */
         __le16 ih_entry_count;
     } __attribute__ ((__packed__)) u;
     __le16 ih_item_len; /* total size of the item body */
 
     /* an offset to the item body within the block */
     __le16 ih_item_location;
 
     /*
      * 0 for all old items, 2 for new ones. Highest bit is set by fsck
      * temporary, cleaned after all done
      */
     __le16 ih_version;
 } __attribute__ ((__packed__));
 /* size of item header     */
 #define IH_SIZE (sizeof(struct item_head))
 
 #define ih_free_space(ih)            le16_to_cpu((ih)->u.ih_free_space_reserved)
 #define ih_version(ih)               le16_to_cpu((ih)->ih_version)
 #define ih_entry_count(ih)           le16_to_cpu((ih)->u.ih_entry_count)
 #define ih_location(ih)              le16_to_cpu((ih)->ih_item_location)
 #define ih_item_len(ih)              le16_to_cpu((ih)->ih_item_len)
 
 #define put_ih_free_space(ih, val)   do { (ih)->u.ih_free_space_reserved = cpu_to_le16(val); } while(0)
 #define put_ih_version(ih, val)      do { (ih)->ih_version = cpu_to_le16(val); } while (0)
 #define put_ih_entry_count(ih, val)  do { (ih)->u.ih_entry_count = cpu_to_le16(val); } while (0)
 #define put_ih_location(ih, val)     do { (ih)->ih_item_location = cpu_to_le16(val); } while (0)
 #define put_ih_item_len(ih, val)     do { (ih)->ih_item_len = cpu_to_le16(val); } while (0)
 
 #define unreachable_item(ih) (ih_version(ih) & (1 << 15))
 
 #define get_ih_free_space(ih) (ih_version (ih) == KEY_FORMAT_3_6 ? 0 : ih_free_space (ih))
 #define set_ih_free_space(ih,val) put_ih_free_space((ih), ((ih_version(ih) == KEY_FORMAT_3_6) ? 0 : (val)))
 
 /*
  * these operate on indirect items, where you've got an array of ints
  * at a possibly unaligned location.  These are a noop on ia32
  *
  * p is the array of __u32, i is the index into the array, v is the value
  * to store there.
  */
 #define get_block_num(p, i) get_unaligned_le32((p) + (i))
 #define put_block_num(p, i, v) put_unaligned_le32((v), (p) + (i))
 
 /* * in old version uniqueness field shows key type */
 #define V1_SD_UNIQUENESS 0
 #define V1_INDIRECT_UNIQUENESS 0xfffffffe
 #define V1_DIRECT_UNIQUENESS 0xffffffff
 #define V1_DIRENTRY_UNIQUENESS 500
 #define V1_ANY_UNIQUENESS 555   /* FIXME: comment is required */
 
 /* here are conversion routines */
 static inline int uniqueness2type(__u32 uniqueness) CONSTF;
 static inline int uniqueness2type(__u32 uniqueness)
 {
     switch ((int)uniqueness) {
     case V1_SD_UNIQUENESS:
         return TYPE_STAT_DATA;
     case V1_INDIRECT_UNIQUENESS:
         return TYPE_INDIRECT;
     case V1_DIRECT_UNIQUENESS:
         return TYPE_DIRECT;
     case V1_DIRENTRY_UNIQUENESS:
         return TYPE_DIRENTRY;
     case V1_ANY_UNIQUENESS:
     default:
         return TYPE_ANY;
     }
 }
 
 static inline __u32 type2uniqueness(int type) CONSTF;
 static inline __u32 type2uniqueness(int type)
 {
     switch (type) {
     case TYPE_STAT_DATA:
         return V1_SD_UNIQUENESS;
     case TYPE_INDIRECT:
         return V1_INDIRECT_UNIQUENESS;
     case TYPE_DIRECT:
         return V1_DIRECT_UNIQUENESS;
     case TYPE_DIRENTRY:
         return V1_DIRENTRY_UNIQUENESS;
     case TYPE_ANY:
     default:
         return V1_ANY_UNIQUENESS;
     }
 }
 
 /*
  * key is pointer to on disk key which is stored in le, result is cpu,
  * there is no way to get version of object from key, so, provide
  * version to these defines
  */
 static inline loff_t le_key_k_offset(int version,
                      const struct reiserfs_key *key)
 {
     return (version == KEY_FORMAT_3_5) ?
         le32_to_cpu(key->u.k_offset_v1.k_offset) :
         offset_v2_k_offset(&(key->u.k_offset_v2));
 }
 
 static inline loff_t le_ih_k_offset(const struct item_head *ih)
 {
     return le_key_k_offset(ih_version(ih), &(ih->ih_key));
 }
 
 static inline loff_t le_key_k_type(int version, const struct reiserfs_key *key)
 {
     if (version == KEY_FORMAT_3_5) {
         loff_t val = le32_to_cpu(key->u.k_offset_v1.k_uniqueness);
         return uniqueness2type(val);
     } else
         return offset_v2_k_type(&(key->u.k_offset_v2));
 }
 
 static inline loff_t le_ih_k_type(const struct item_head *ih)
 {
     return le_key_k_type(ih_version(ih), &(ih->ih_key));
 }
 
 static inline void set_le_key_k_offset(int version, struct reiserfs_key *key,
                        loff_t offset)
 {
     if (version == KEY_FORMAT_3_5)
         key->u.k_offset_v1.k_offset = cpu_to_le32(offset);
     else
         set_offset_v2_k_offset(&key->u.k_offset_v2, offset);
 }
 
 static inline void add_le_key_k_offset(int version, struct reiserfs_key *key,
                        loff_t offset)
 {
     set_le_key_k_offset(version, key,
                 le_key_k_offset(version, key) + offset);
 }
 
 static inline void add_le_ih_k_offset(struct item_head *ih, loff_t offset)
 {
     add_le_key_k_offset(ih_version(ih), &(ih->ih_key), offset);
 }
 
 static inline void set_le_ih_k_offset(struct item_head *ih, loff_t offset)
 {
     set_le_key_k_offset(ih_version(ih), &(ih->ih_key), offset);
 }
 
 static inline void set_le_key_k_type(int version, struct reiserfs_key *key,
                      int type)
 {
     if (version == KEY_FORMAT_3_5) {
         type = type2uniqueness(type);
         key->u.k_offset_v1.k_uniqueness = cpu_to_le32(type);
     } else
            set_offset_v2_k_type(&key->u.k_offset_v2, type);
 }
 
 static inline void set_le_ih_k_type(struct item_head *ih, int type)
 {
     set_le_key_k_type(ih_version(ih), &(ih->ih_key), type);
 }
 
 static inline int is_direntry_le_key(int version, struct reiserfs_key *key)
 {
     return le_key_k_type(version, key) == TYPE_DIRENTRY;
 }
 
 static inline int is_direct_le_key(int version, struct reiserfs_key *key)
 {
     return le_key_k_type(version, key) == TYPE_DIRECT;
 }
 
 static inline int is_indirect_le_key(int version, struct reiserfs_key *key)
 {
     return le_key_k_type(version, key) == TYPE_INDIRECT;
 }
 
 static inline int is_statdata_le_key(int version, struct reiserfs_key *key)
 {
     return le_key_k_type(version, key) == TYPE_STAT_DATA;
 }
 
 /* item header has version.  */
 static inline int is_direntry_le_ih(struct item_head *ih)
 {
     return is_direntry_le_key(ih_version(ih), &ih->ih_key);
 }
 
 static inline int is_direct_le_ih(struct item_head *ih)
 {
     return is_direct_le_key(ih_version(ih), &ih->ih_key);
 }
 
 static inline int is_indirect_le_ih(struct item_head *ih)
 {
     return is_indirect_le_key(ih_version(ih), &ih->ih_key);
 }
 
 static inline int is_statdata_le_ih(struct item_head *ih)
 {
     return is_statdata_le_key(ih_version(ih), &ih->ih_key);
 }
 
 /* key is pointer to cpu key, result is cpu */
 static inline loff_t cpu_key_k_offset(const struct cpu_key *key)
 {
     return key->on_disk_key.k_offset;
 }
 
 static inline loff_t cpu_key_k_type(const struct cpu_key *key)
 {
     return key->on_disk_key.k_type;
 }
 
 static inline void set_cpu_key_k_offset(struct cpu_key *key, loff_t offset)
 {
     key->on_disk_key.k_offset = offset;
 }
 
 static inline void set_cpu_key_k_type(struct cpu_key *key, int type)
 {
     key->on_disk_key.k_type = type;
 }
 
 static inline void cpu_key_k_offset_dec(struct cpu_key *key)
 {
     key->on_disk_key.k_offset--;
 }
 
 #define is_direntry_cpu_key(key) (cpu_key_k_type (key) == TYPE_DIRENTRY)
 #define is_direct_cpu_key(key) (cpu_key_k_type (key) == TYPE_DIRECT)
 #define is_indirect_cpu_key(key) (cpu_key_k_type (key) == TYPE_INDIRECT)
 #define is_statdata_cpu_key(key) (cpu_key_k_type (key) == TYPE_STAT_DATA)
 
 /* are these used ? */
 #define is_direntry_cpu_ih(ih) (is_direntry_cpu_key (&((ih)->ih_key)))
 #define is_direct_cpu_ih(ih) (is_direct_cpu_key (&((ih)->ih_key)))
 #define is_indirect_cpu_ih(ih) (is_indirect_cpu_key (&((ih)->ih_key)))
 #define is_statdata_cpu_ih(ih) (is_statdata_cpu_key (&((ih)->ih_key)))
 
 #define I_K_KEY_IN_ITEM(ih, key, n_blocksize) \
     (!COMP_SHORT_KEYS(ih, key) && \
       I_OFF_BYTE_IN_ITEM(ih, k_offset(key), n_blocksize))
 
 /* maximal length of item */
 #define MAX_ITEM_LEN(block_size) (block_size - BLKH_SIZE - IH_SIZE)
 #define MIN_ITEM_LEN 1
 
 /* object identifier for root dir */
 #define REISERFS_ROOT_OBJECTID 2
 #define REISERFS_ROOT_PARENT_OBJECTID 1
 
 extern struct reiserfs_key root_key;
 
 /*
  * Picture represents a leaf of the S+tree
  *  ______________________________________________________
  * |      |  Array of     |                   |           |
  * |Block |  Object-Item  |      F r e e      |  Objects- |
  * | head |  Headers      |     S p a c e     |   Items   |
  * |______|_______________|___________________|___________|
  */
 
 /*
  * Header of a disk block.  More precisely, header of a formatted leaf
  * or internal node, and not the header of an unformatted node.
  */
 struct block_head {
     __le16 blk_level;   /* Level of a block in the tree. */
     __le16 blk_nr_item; /* Number of keys/items in a block. */
     __le16 blk_free_space;  /* Block free space in bytes. */
     __le16 blk_reserved;
     /* dump this in v4/planA */
 
     /* kept only for compatibility */
     struct reiserfs_key blk_right_delim_key;
 };
 
 #define BLKH_SIZE                     (sizeof(struct block_head))
 #define blkh_level(p_blkh)            (le16_to_cpu((p_blkh)->blk_level))
 #define blkh_nr_item(p_blkh)          (le16_to_cpu((p_blkh)->blk_nr_item))
 #define blkh_free_space(p_blkh)       (le16_to_cpu((p_blkh)->blk_free_space))
 #define blkh_reserved(p_blkh)         (le16_to_cpu((p_blkh)->blk_reserved))
 #define set_blkh_level(p_blkh,val)    ((p_blkh)->blk_level = cpu_to_le16(val))
 #define set_blkh_nr_item(p_blkh,val)  ((p_blkh)->blk_nr_item = cpu_to_le16(val))
 #define set_blkh_free_space(p_blkh,val) ((p_blkh)->blk_free_space = cpu_to_le16(val))
 #define set_blkh_reserved(p_blkh,val) ((p_blkh)->blk_reserved = cpu_to_le16(val))
 #define blkh_right_delim_key(p_blkh)  ((p_blkh)->blk_right_delim_key)
 #define set_blkh_right_delim_key(p_blkh,val)  ((p_blkh)->blk_right_delim_key = val)
 
 /* values for blk_level field of the struct block_head */
 
 /*
  * When node gets removed from the tree its blk_level is set to FREE_LEVEL.
  * It is then  used to see whether the node is still in the tree
  */
 #define FREE_LEVEL 0
 
 #define DISK_LEAF_NODE_LEVEL  1 /* Leaf node level. */
 
 /*
  * Given the buffer head of a formatted node, resolve to the
  * block head of that node.
  */
 #define B_BLK_HEAD(bh)          ((struct block_head *)((bh)->b_data))
 /* Number of items that are in buffer. */
 #define B_NR_ITEMS(bh)          (blkh_nr_item(B_BLK_HEAD(bh)))
 #define B_LEVEL(bh)         (blkh_level(B_BLK_HEAD(bh)))
 #define B_FREE_SPACE(bh)        (blkh_free_space(B_BLK_HEAD(bh)))
 
 #define PUT_B_NR_ITEMS(bh, val)     do { set_blkh_nr_item(B_BLK_HEAD(bh), val); } while (0)
 #define PUT_B_LEVEL(bh, val)        do { set_blkh_level(B_BLK_HEAD(bh), val); } while (0)
 #define PUT_B_FREE_SPACE(bh, val)   do { set_blkh_free_space(B_BLK_HEAD(bh), val); } while (0)
 
 /* Get right delimiting key. -- little endian */
 #define B_PRIGHT_DELIM_KEY(bh)      (&(blk_right_delim_key(B_BLK_HEAD(bh))))
 
 /* Does the buffer contain a disk leaf. */
 #define B_IS_ITEMS_LEVEL(bh)        (B_LEVEL(bh) == DISK_LEAF_NODE_LEVEL)
 
 /* Does the buffer contain a disk internal node */
 #define B_IS_KEYS_LEVEL(bh)      (B_LEVEL(bh) > DISK_LEAF_NODE_LEVEL \
                         && B_LEVEL(bh) <= MAX_HEIGHT)
 
 /***************************************************************************
  *                             STAT DATA                                   *
  ***************************************************************************/
 
 /*
  * old stat data is 32 bytes long. We are going to distinguish new one by
  * different size
 */
 struct stat_data_v1 {
     __le16 sd_mode;     /* file type, permissions */
     __le16 sd_nlink;    /* number of hard links */
     __le16 sd_uid;      /* owner */
     __le16 sd_gid;      /* group */
     __le32 sd_size;     /* file size */
     __le32 sd_atime;    /* time of last access */
     __le32 sd_mtime;    /* time file was last modified  */
 
     /*
      * time inode (stat data) was last changed
      * (except changes to sd_atime and sd_mtime)
      */
     __le32 sd_ctime;
     union {
         __le32 sd_rdev;
         __le32 sd_blocks;   /* number of blocks file uses */
     } __attribute__ ((__packed__)) u;
 
     /*
      * first byte of file which is stored in a direct item: except that if
      * it equals 1 it is a symlink and if it equals ~(__u32)0 there is no
      * direct item.  The existence of this field really grates on me.
      * Let's replace it with a macro based on sd_size and our tail
      * suppression policy.  Someday.  -Hans
      */
     __le32 sd_first_direct_byte;
 } __attribute__ ((__packed__));
 
 #define SD_V1_SIZE              (sizeof(struct stat_data_v1))
 #define stat_data_v1(ih)        (ih_version (ih) == KEY_FORMAT_3_5)
 #define sd_v1_mode(sdp)         (le16_to_cpu((sdp)->sd_mode))
 #define set_sd_v1_mode(sdp,v)   ((sdp)->sd_mode = cpu_to_le16(v))
 #define sd_v1_nlink(sdp)        (le16_to_cpu((sdp)->sd_nlink))
 #define set_sd_v1_nlink(sdp,v)  ((sdp)->sd_nlink = cpu_to_le16(v))
 #define sd_v1_uid(sdp)          (le16_to_cpu((sdp)->sd_uid))
 #define set_sd_v1_uid(sdp,v)    ((sdp)->sd_uid = cpu_to_le16(v))
 #define sd_v1_gid(sdp)          (le16_to_cpu((sdp)->sd_gid))
 #define set_sd_v1_gid(sdp,v)    ((sdp)->sd_gid = cpu_to_le16(v))
 #define sd_v1_size(sdp)         (le32_to_cpu((sdp)->sd_size))
 #define set_sd_v1_size(sdp,v)   ((sdp)->sd_size = cpu_to_le32(v))
 #define sd_v1_atime(sdp)        (le32_to_cpu((sdp)->sd_atime))
 #define set_sd_v1_atime(sdp,v)  ((sdp)->sd_atime = cpu_to_le32(v))
 #define sd_v1_mtime(sdp)        (le32_to_cpu((sdp)->sd_mtime))
 #define set_sd_v1_mtime(sdp,v)  ((sdp)->sd_mtime = cpu_to_le32(v))
 #define sd_v1_ctime(sdp)        (le32_to_cpu((sdp)->sd_ctime))
 #define set_sd_v1_ctime(sdp,v)  ((sdp)->sd_ctime = cpu_to_le32(v))
 #define sd_v1_rdev(sdp)         (le32_to_cpu((sdp)->u.sd_rdev))
 #define set_sd_v1_rdev(sdp,v)   ((sdp)->u.sd_rdev = cpu_to_le32(v))
 #define sd_v1_blocks(sdp)       (le32_to_cpu((sdp)->u.sd_blocks))
 #define set_sd_v1_blocks(sdp,v) ((sdp)->u.sd_blocks = cpu_to_le32(v))
 #define sd_v1_first_direct_byte(sdp) \
                                 (le32_to_cpu((sdp)->sd_first_direct_byte))
 #define set_sd_v1_first_direct_byte(sdp,v) \
                                 ((sdp)->sd_first_direct_byte = cpu_to_le32(v))
 
 /* inode flags stored in sd_attrs (nee sd_reserved) */
 
 /*
  * we want common flags to have the same values as in ext2,
  * so chattr(1) will work without problems
  */
 #define REISERFS_IMMUTABLE_FL FS_IMMUTABLE_FL
 #define REISERFS_APPEND_FL    FS_APPEND_FL
 #define REISERFS_SYNC_FL      FS_SYNC_FL
 #define REISERFS_NOATIME_FL   FS_NOATIME_FL
 #define REISERFS_NODUMP_FL    FS_NODUMP_FL
 #define REISERFS_SECRM_FL     FS_SECRM_FL
 #define REISERFS_UNRM_FL      FS_UNRM_FL
 #define REISERFS_COMPR_FL     FS_COMPR_FL
 #define REISERFS_NOTAIL_FL    FS_NOTAIL_FL
 
 /* persistent flags that file inherits from the parent directory */
 #define REISERFS_INHERIT_MASK ( REISERFS_IMMUTABLE_FL | \
                 REISERFS_SYNC_FL |  \
                 REISERFS_NOATIME_FL |   \
                 REISERFS_NODUMP_FL |    \
                 REISERFS_SECRM_FL | \
                 REISERFS_COMPR_FL | \
                 REISERFS_NOTAIL_FL )
 
 /*
  * Stat Data on disk (reiserfs version of UFS disk inode minus the
  * address blocks)
  */
 struct stat_data {
     __le16 sd_mode;     /* file type, permissions */
     __le16 sd_attrs;    /* persistent inode flags */
     __le32 sd_nlink;    /* number of hard links */
     __le64 sd_size;     /* file size */
     __le32 sd_uid;      /* owner */
     __le32 sd_gid;      /* group */
     __le32 sd_atime;    /* time of last access */
     __le32 sd_mtime;    /* time file was last modified  */
 
     /*
      * time inode (stat data) was last changed
      * (except changes to sd_atime and sd_mtime)
      */
     __le32 sd_ctime;
     __le32 sd_blocks;
     union {
         __le32 sd_rdev;
         __le32 sd_generation;
     } __attribute__ ((__packed__)) u;
 } __attribute__ ((__packed__));
 
 /* this is 44 bytes long */
 #define SD_SIZE (sizeof(struct stat_data))
 #define SD_V2_SIZE              SD_SIZE
 #define stat_data_v2(ih)        (ih_version (ih) == KEY_FORMAT_3_6)
 #define sd_v2_mode(sdp)         (le16_to_cpu((sdp)->sd_mode))
 #define set_sd_v2_mode(sdp,v)   ((sdp)->sd_mode = cpu_to_le16(v))
 /* sd_reserved */
 /* set_sd_reserved */
 #define sd_v2_nlink(sdp)        (le32_to_cpu((sdp)->sd_nlink))
 #define set_sd_v2_nlink(sdp,v)  ((sdp)->sd_nlink = cpu_to_le32(v))
 #define sd_v2_size(sdp)         (le64_to_cpu((sdp)->sd_size))
 #define set_sd_v2_size(sdp,v)   ((sdp)->sd_size = cpu_to_le64(v))
 #define sd_v2_uid(sdp)          (le32_to_cpu((sdp)->sd_uid))
 #define set_sd_v2_uid(sdp,v)    ((sdp)->sd_uid = cpu_to_le32(v))
 #define sd_v2_gid(sdp)          (le32_to_cpu((sdp)->sd_gid))
 #define set_sd_v2_gid(sdp,v)    ((sdp)->sd_gid = cpu_to_le32(v))
 #define sd_v2_atime(sdp)        (le32_to_cpu((sdp)->sd_atime))
 #define set_sd_v2_atime(sdp,v)  ((sdp)->sd_atime = cpu_to_le32(v))
 #define sd_v2_mtime(sdp)        (le32_to_cpu((sdp)->sd_mtime))
 #define set_sd_v2_mtime(sdp,v)  ((sdp)->sd_mtime = cpu_to_le32(v))
 #define sd_v2_ctime(sdp)        (le32_to_cpu((sdp)->sd_ctime))
 #define set_sd_v2_ctime(sdp,v)  ((sdp)->sd_ctime = cpu_to_le32(v))
 #define sd_v2_blocks(sdp)       (le32_to_cpu((sdp)->sd_blocks))
 #define set_sd_v2_blocks(sdp,v) ((sdp)->sd_blocks = cpu_to_le32(v))
 #define sd_v2_rdev(sdp)         (le32_to_cpu((sdp)->u.sd_rdev))
 #define set_sd_v2_rdev(sdp,v)   ((sdp)->u.sd_rdev = cpu_to_le32(v))
 #define sd_v2_generation(sdp)   (le32_to_cpu((sdp)->u.sd_generation))
 #define set_sd_v2_generation(sdp,v) ((sdp)->u.sd_generation = cpu_to_le32(v))
 #define sd_v2_attrs(sdp)         (le16_to_cpu((sdp)->sd_attrs))
 #define set_sd_v2_attrs(sdp,v)   ((sdp)->sd_attrs = cpu_to_le16(v))
 
 /***************************************************************************
  *                      DIRECTORY STRUCTURE                                *
  ***************************************************************************/
 /*
  * Picture represents the structure of directory items
  * ________________________________________________
  * |  Array of     |   |     |        |       |   |
  * | directory     |N-1| N-2 | ....   |   1st |0th|
  * | entry headers |   |     |        |       |   |
  * |_______________|___|_____|________|_______|___|
  *                  <----   directory entries         ------>
  *
  * First directory item has k_offset component 1. We store "." and ".."
  * in one item, always, we never split "." and ".." into differing
  * items.  This makes, among other things, the code for removing
  * directories simpler.
  */
 #define SD_OFFSET  0
 #define SD_UNIQUENESS 0
 #define DOT_OFFSET 1
 #define DOT_DOT_OFFSET 2
 #define DIRENTRY_UNIQUENESS 500
 
 #define FIRST_ITEM_OFFSET 1
 
 /*
  * Q: How to get key of object pointed to by entry from entry?
  *
  * A: Each directory entry has its header. This header has deh_dir_id
  *    and deh_objectid fields, those are key of object, entry points to
  */
 
 /*
  * NOT IMPLEMENTED:
  * Directory will someday contain stat data of object
  */
 
 struct reiserfs_de_head {
     __le32 deh_offset;  /* third component of the directory entry key */
 
     /*
      * objectid of the parent directory of the object, that is referenced
      * by directory entry
      */
     __le32 deh_dir_id;
 
     /* objectid of the object, that is referenced by directory entry */
     __le32 deh_objectid;
     __le16 deh_location;    /* offset of name in the whole item */
 
     /*
      * whether 1) entry contains stat data (for future), and
      * 2) whether entry is hidden (unlinked)
      */
     __le16 deh_state;
 } __attribute__ ((__packed__));
 #define DEH_SIZE                  sizeof(struct reiserfs_de_head)
 #define deh_offset(p_deh)         (le32_to_cpu((p_deh)->deh_offset))
 #define deh_dir_id(p_deh)         (le32_to_cpu((p_deh)->deh_dir_id))
 #define deh_objectid(p_deh)       (le32_to_cpu((p_deh)->deh_objectid))
 #define deh_location(p_deh)       (le16_to_cpu((p_deh)->deh_location))
 #define deh_state(p_deh)          (le16_to_cpu((p_deh)->deh_state))
 
 #define put_deh_offset(p_deh,v)   ((p_deh)->deh_offset = cpu_to_le32((v)))
 #define put_deh_dir_id(p_deh,v)   ((p_deh)->deh_dir_id = cpu_to_le32((v)))
 #define put_deh_objectid(p_deh,v) ((p_deh)->deh_objectid = cpu_to_le32((v)))
 #define put_deh_location(p_deh,v) ((p_deh)->deh_location = cpu_to_le16((v)))
 #define put_deh_state(p_deh,v)    ((p_deh)->deh_state = cpu_to_le16((v)))
 
 /* empty directory contains two entries "." and ".." and their headers */
 #define EMPTY_DIR_SIZE \
 (DEH_SIZE * 2 + ROUND_UP (sizeof(".") - 1) + ROUND_UP (sizeof("..") - 1))
 
 /* old format directories have this size when empty */
 #define EMPTY_DIR_SIZE_V1 (DEH_SIZE * 2 + 3)
 
 #define DEH_Statdata 0      /* not used now */
 #define DEH_Visible 2
 
 /* 64 bit systems (and the S/390) need to be aligned explicitly -jdm */
 #if BITS_PER_LONG == 64 || defined(__s390__) || defined(__hppa__)
 #   define ADDR_UNALIGNED_BITS  (3)
 #endif
 
 /*
  * These are only used to manipulate deh_state.
  * Because of this, we'll use the ext2_ bit routines,
  * since they are little endian
  */
 #ifdef ADDR_UNALIGNED_BITS
 
 #   define aligned_address(addr)           ((void *)((long)(addr) & ~((1UL << ADDR_UNALIGNED_BITS) - 1)))
 #   define unaligned_offset(addr)          (((int)((long)(addr) & ((1 << ADDR_UNALIGNED_BITS) - 1))) << 3)
 
 #   define set_bit_unaligned(nr, addr)  \
     __test_and_set_bit_le((nr) + unaligned_offset(addr), aligned_address(addr))
 #   define clear_bit_unaligned(nr, addr)    \
     __test_and_clear_bit_le((nr) + unaligned_offset(addr), aligned_address(addr))
 #   define test_bit_unaligned(nr, addr) \
     test_bit_le((nr) + unaligned_offset(addr), aligned_address(addr))
 
 #else
 
 #   define set_bit_unaligned(nr, addr)  __test_and_set_bit_le(nr, addr)
 #   define clear_bit_unaligned(nr, addr)    __test_and_clear_bit_le(nr, addr)
 #   define test_bit_unaligned(nr, addr) test_bit_le(nr, addr)
 
 #endif
 
 #define mark_de_with_sd(deh)        set_bit_unaligned (DEH_Statdata, &((deh)->deh_state))
 #define mark_de_without_sd(deh)     clear_bit_unaligned (DEH_Statdata, &((deh)->deh_state))
 #define mark_de_visible(deh)        set_bit_unaligned (DEH_Visible, &((deh)->deh_state))
 #define mark_de_hidden(deh)     clear_bit_unaligned (DEH_Visible, &((deh)->deh_state))
 
 #define de_with_sd(deh)         test_bit_unaligned (DEH_Statdata, &((deh)->deh_state))
 #define de_visible(deh)             test_bit_unaligned (DEH_Visible, &((deh)->deh_state))
 #define de_hidden(deh)              !test_bit_unaligned (DEH_Visible, &((deh)->deh_state))
 
 extern void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
                    __le32 par_dirid, __le32 par_objid);
 extern void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
                 __le32 par_dirid, __le32 par_objid);
 
 /* two entries per block (at least) */
 #define REISERFS_MAX_NAME(block_size) 255
 
 /*
  * this structure is used for operations on directory entries. It is
  * not a disk structure.
  *
  * When reiserfs_find_entry or search_by_entry_key find directory
  * entry, they return filled reiserfs_dir_entry structure
  */
 struct reiserfs_dir_entry {
     struct buffer_head *de_bh;
     int de_item_num;
     struct item_head *de_ih;
     int de_entry_num;
     struct reiserfs_de_head *de_deh;
     int de_entrylen;
     int de_namelen;
     char *de_name;
     unsigned long *de_gen_number_bit_string;
 
     __u32 de_dir_id;
     __u32 de_objectid;
 
     struct cpu_key de_entry_key;
 };
 
 /*
  * these defines are useful when a particular member of
  * a reiserfs_dir_entry is needed
  */
 
 /* pointer to file name, stored in entry */
 #define B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh) \
                 (ih_item_body(bh, ih) + deh_location(deh))
 
 /* length of name */
 #define I_DEH_N_ENTRY_FILE_NAME_LENGTH(ih,deh,entry_num) \
 (I_DEH_N_ENTRY_LENGTH (ih, deh, entry_num) - (de_with_sd (deh) ? SD_SIZE : 0))
 
 /* hash value occupies bits from 7 up to 30 */
 #define GET_HASH_VALUE(offset) ((offset) & 0x7fffff80LL)
 /* generation number occupies 7 bits starting from 0 up to 6 */
 #define GET_GENERATION_NUMBER(offset) ((offset) & 0x7fLL)
 #define MAX_GENERATION_NUMBER  127
 
 #define SET_GENERATION_NUMBER(offset,gen_number) (GET_HASH_VALUE(offset)|(gen_number))
 
 /*
  * Picture represents an internal node of the reiserfs tree
  *  ______________________________________________________
  * |      |  Array of     |  Array of         |  Free     |
  * |block |    keys       |  pointers         | space     |
  * | head |      N        |      N+1          |           |
  * |______|_______________|___________________|___________|
  */
 
 /***************************************************************************
  *                      DISK CHILD                                         *
  ***************************************************************************/
 /*
  * Disk child pointer:
  * The pointer from an internal node of the tree to a node that is on disk.
  */
 struct disk_child {
     __le32 dc_block_number; /* Disk child's block number. */
     __le16 dc_size;     /* Disk child's used space.   */
     __le16 dc_reserved;
 };
 
 #define DC_SIZE (sizeof(struct disk_child))
 #define dc_block_number(dc_p)   (le32_to_cpu((dc_p)->dc_block_number))
 #define dc_size(dc_p)       (le16_to_cpu((dc_p)->dc_size))
 #define put_dc_block_number(dc_p, val)   do { (dc_p)->dc_block_number = cpu_to_le32(val); } while(0)
 #define put_dc_size(dc_p, val)   do { (dc_p)->dc_size = cpu_to_le16(val); } while(0)
 
 /* Get disk child by buffer header and position in the tree node. */
 #define B_N_CHILD(bh, n_pos)  ((struct disk_child *)\
 ((bh)->b_data + BLKH_SIZE + B_NR_ITEMS(bh) * KEY_SIZE + DC_SIZE * (n_pos)))
 
 /* Get disk child number by buffer header and position in the tree node. */
 #define B_N_CHILD_NUM(bh, n_pos) (dc_block_number(B_N_CHILD(bh, n_pos)))
 #define PUT_B_N_CHILD_NUM(bh, n_pos, val) \
                 (put_dc_block_number(B_N_CHILD(bh, n_pos), val))
 
  /* maximal value of field child_size in structure disk_child */
  /* child size is the combined size of all items and their headers */
 #define MAX_CHILD_SIZE(bh) ((int)( (bh)->b_size - BLKH_SIZE ))
 
 /* amount of used space in buffer (not including block head) */
 #define B_CHILD_SIZE(cur) (MAX_CHILD_SIZE(cur)-(B_FREE_SPACE(cur)))
 
 /* max and min number of keys in internal node */
 #define MAX_NR_KEY(bh) ( (MAX_CHILD_SIZE(bh)-DC_SIZE)/(KEY_SIZE+DC_SIZE) )
 #define MIN_NR_KEY(bh)    (MAX_NR_KEY(bh)/2)
 
 /***************************************************************************
  *                      PATH STRUCTURES AND DEFINES                        *
  ***************************************************************************/
 
 /*
  * search_by_key fills up the path from the root to the leaf as it descends
  * the tree looking for the key.  It uses reiserfs_bread to try to find
  * buffers in the cache given their block number.  If it does not find
  * them in the cache it reads them from disk.  For each node search_by_key
  * finds using reiserfs_bread it then uses bin_search to look through that
  * node.  bin_search will find the position of the block_number of the next
  * node if it is looking through an internal node.  If it is looking through
  * a leaf node bin_search will find the position of the item which has key
  * either equal to given key, or which is the maximal key less than the
  * given key.
  */
 
 struct path_element {
     /* Pointer to the buffer at the path in the tree. */
     struct buffer_head *pe_buffer;
     /* Position in the tree node which is placed in the buffer above. */
     int pe_position;
 };
 
 /*
  * maximal height of a tree. don't change this without
  * changing JOURNAL_PER_BALANCE_CNT
  */
 #define MAX_HEIGHT 5
 
 /* Must be equals MAX_HEIGHT + FIRST_PATH_ELEMENT_OFFSET */
 #define EXTENDED_MAX_HEIGHT         7
 
 /* Must be equal to at least 2. */
 #define FIRST_PATH_ELEMENT_OFFSET   2
 
 /* Must be equal to FIRST_PATH_ELEMENT_OFFSET - 1 */
 #define ILLEGAL_PATH_ELEMENT_OFFSET 1
 
 /* this MUST be MAX_HEIGHT + 1. See about FEB below */
 #define MAX_FEB_SIZE 6
 
 /*
  * We need to keep track of who the ancestors of nodes are.  When we
  * perform a search we record which nodes were visited while
  * descending the tree looking for the node we searched for. This list
  * of nodes is called the path.  This information is used while
  * performing balancing.  Note that this path information may become
  * invalid, and this means we must check it when using it to see if it
  * is still valid. You'll need to read search_by_key and the comments
  * in it, especially about decrement_counters_in_path(), to understand
  * this structure.
  *
  * Paths make the code so much harder to work with and debug.... An
  * enormous number of bugs are due to them, and trying to write or modify
  * code that uses them just makes my head hurt.  They are based on an
  * excessive effort to avoid disturbing the precious VFS code.:-( The
  * gods only know how we are going to SMP the code that uses them.
  * znodes are the way!
  */
 
 #define PATH_READA  0x1 /* do read ahead */
 #define PATH_READA_BACK 0x2 /* read backwards */
 
 struct treepath {
     int path_length;    /* Length of the array above.   */
     int reada;
     /* Array of the path elements.  */
     struct path_element path_elements[EXTENDED_MAX_HEIGHT];
     int pos_in_item;
 };
 
 #define pos_in_item(path) ((path)->pos_in_item)
 
 #define INITIALIZE_PATH(var) \
 struct treepath var = {.path_length = ILLEGAL_PATH_ELEMENT_OFFSET, .reada = 0,}
 
 /* Get path element by path and path position. */
 #define PATH_OFFSET_PELEMENT(path, n_offset)  ((path)->path_elements + (n_offset))
 
 /* Get buffer header at the path by path and path position. */
 #define PATH_OFFSET_PBUFFER(path, n_offset)   (PATH_OFFSET_PELEMENT(path, n_offset)->pe_buffer)
 
 /* Get position in the element at the path by path and path position. */
 #define PATH_OFFSET_POSITION(path, n_offset) (PATH_OFFSET_PELEMENT(path, n_offset)->pe_position)
 
 #define PATH_PLAST_BUFFER(path) (PATH_OFFSET_PBUFFER((path), (path)->path_length))
 
 /*
  * you know, to the person who didn't write this the macro name does not
  * at first suggest what it does.  Maybe POSITION_FROM_PATH_END? Or
  * maybe we should just focus on dumping paths... -Hans
  */
 #define PATH_LAST_POSITION(path) (PATH_OFFSET_POSITION((path), (path)->path_length))
 
 /*
  * in do_balance leaf has h == 0 in contrast with path structure,
  * where root has level == 0. That is why we need these defines
  */
 
 /* tb->S[h] */
 #define PATH_H_PBUFFER(path, h) \
             PATH_OFFSET_PBUFFER(path, path->path_length - (h))
 
 /* tb->F[h] or tb->S[0]->b_parent */
 #define PATH_H_PPARENT(path, h) PATH_H_PBUFFER(path, (h) + 1)
 
 #define PATH_H_POSITION(path, h) \
             PATH_OFFSET_POSITION(path, path->path_length - (h))
 
 /* tb->S[h]->b_item_order */
 #define PATH_H_B_ITEM_ORDER(path, h) PATH_H_POSITION(path, h + 1)
 
 #define PATH_H_PATH_OFFSET(path, n_h) ((path)->path_length - (n_h))
 
 static inline void *reiserfs_node_data(const struct buffer_head *bh)
 {
     return bh->b_data + sizeof(struct block_head);
 }
 
 /* get key from internal node */
 static inline struct reiserfs_key *internal_key(struct buffer_head *bh,
                         int item_num)
 {
     struct reiserfs_key *key = reiserfs_node_data(bh);
 
     return &key[item_num];
 }
 
 /* get the item header from leaf node */
 static inline struct item_head *item_head(const struct buffer_head *bh,
                       int item_num)
 {
     struct item_head *ih = reiserfs_node_data(bh);
 
     return &ih[item_num];
 }
 
 /* get the key from leaf node */
 static inline struct reiserfs_key *leaf_key(const struct buffer_head *bh,
                         int item_num)
 {
     return &item_head(bh, item_num)->ih_key;
 }
 
 static inline void *ih_item_body(const struct buffer_head *bh,
                  const struct item_head *ih)
 {
     return bh->b_data + ih_location(ih);
 }
 
 /* get item body from leaf node */
 static inline void *item_body(const struct buffer_head *bh, int item_num)
 {
     return ih_item_body(bh, item_head(bh, item_num));
 }
 
 static inline struct item_head *tp_item_head(const struct treepath *path)
 {
     return item_head(PATH_PLAST_BUFFER(path), PATH_LAST_POSITION(path));
 }
 
 static inline void *tp_item_body(const struct treepath *path)
 {
     return item_body(PATH_PLAST_BUFFER(path), PATH_LAST_POSITION(path));
 }
 
 #define get_last_bh(path) PATH_PLAST_BUFFER(path)
 #define get_item_pos(path) PATH_LAST_POSITION(path)
 #define item_moved(ih,path) comp_items(ih, path)
 #define path_changed(ih,path) comp_items (ih, path)
 
 /* array of the entry headers */
  /* get item body */
 #define B_I_DEH(bh, ih) ((struct reiserfs_de_head *)(ih_item_body(bh, ih)))
 
 /*
  * length of the directory entry in directory item. This define
  * calculates length of i-th directory entry using directory entry
  * locations from dir entry head. When it calculates length of 0-th
  * directory entry, it uses length of whole item in place of entry
  * location of the non-existent following entry in the calculation.
  * See picture above.
  */
 static inline int entry_length(const struct buffer_head *bh,
                    const struct item_head *ih, int pos_in_item)
 {
     struct reiserfs_de_head *deh;
 
     deh = B_I_DEH(bh, ih) + pos_in_item;
     if (pos_in_item)
         return deh_location(deh - 1) - deh_location(deh);
 
     return ih_item_len(ih) - deh_location(deh);
 }
 
 /***************************************************************************
  *                       MISC                                              *
  ***************************************************************************/
 
 /* Size of pointer to the unformatted node. */
 #define UNFM_P_SIZE (sizeof(unp_t))
 #define UNFM_P_SHIFT 2
 
 /* in in-core inode key is stored on le form */
 #define INODE_PKEY(inode) ((struct reiserfs_key *)(REISERFS_I(inode)->i_key))
 
 #define MAX_UL_INT 0xffffffff
 #define MAX_INT    0x7ffffff
 #define MAX_US_INT 0xffff
 
 // reiserfs version 2 has max offset 60 bits. Version 1 - 32 bit offset
 static inline loff_t max_reiserfs_offset(struct inode *inode)
 {
     if (get_inode_item_key_version(inode) == KEY_FORMAT_3_5)
         return (loff_t) U32_MAX;
 
     return (loff_t) ((~(__u64) 0) >> 4);
 }
 
 #define MAX_KEY_OBJECTID    MAX_UL_INT
 
 #define MAX_B_NUM  MAX_UL_INT
 #define MAX_FC_NUM MAX_US_INT
 
 /* the purpose is to detect overflow of an unsigned short */
 #define REISERFS_LINK_MAX (MAX_US_INT - 1000)
 
 /*
  * The following defines are used in reiserfs_insert_item
  * and reiserfs_append_item
  */
 #define REISERFS_KERNEL_MEM     0   /* kernel memory mode */
 #define REISERFS_USER_MEM       1   /* user memory mode */
 
 #define fs_generation(s) (REISERFS_SB(s)->s_generation_counter)
 #define get_generation(s) atomic_read (&fs_generation(s))
 #define FILESYSTEM_CHANGED_TB(tb)  (get_generation((tb)->tb_sb) != (tb)->fs_gen)
 #define __fs_changed(gen,s) (gen != get_generation (s))
 #define fs_changed(gen,s)       \
 ({                  \
     reiserfs_cond_resched(s);   \
     __fs_changed(gen, s);       \
 })
 
 /***************************************************************************
  *                  FIXATE NODES                                           *
  ***************************************************************************/
 
 #define VI_TYPE_LEFT_MERGEABLE 1
 #define VI_TYPE_RIGHT_MERGEABLE 2
 
 /*
  * To make any changes in the tree we always first find node, that
  * contains item to be changed/deleted or place to insert a new
  * item. We call this node S. To do balancing we need to decide what
  * we will shift to left/right neighbor, or to a new node, where new
  * item will be etc. To make this analysis simpler we build virtual
  * node. Virtual node is an array of items, that will replace items of
  * node S. (For instance if we are going to delete an item, virtual
  * node does not contain it). Virtual node keeps information about
  * item sizes and types, mergeability of first and last items, sizes
  * of all entries in directory item. We use this array of items when
  * calculating what we can shift to neighbors and how many nodes we
  * have to have if we do not any shiftings, if we shift to left/right
  * neighbor or to both.
  */
 struct virtual_item {
     int vi_index;       /* index in the array of item operations */
     unsigned short vi_type; /* left/right mergeability */
 
     /* length of item that it will have after balancing */
     unsigned short vi_item_len;
 
     struct item_head *vi_ih;
     const char *vi_item;    /* body of item (old or new) */
     const void *vi_new_data;    /* 0 always but paste mode */
     void *vi_uarea;     /* item specific area */
 };
 
 struct virtual_node {
     /* this is a pointer to the free space in the buffer */
     char *vn_free_ptr;
 
     unsigned short vn_nr_item;  /* number of items in virtual node */
 
     /*
      * size of node , that node would have if it has
      * unlimited size and no balancing is performed
      */
     short vn_size;
 
     /* mode of balancing (paste, insert, delete, cut) */
     short vn_mode;
 
     short vn_affected_item_num;
     short vn_pos_in_item;
 
     /* item header of inserted item, 0 for other modes */
     struct item_head *vn_ins_ih;
     const void *vn_data;
 
     /* array of items (including a new one, excluding item to be deleted) */
     struct virtual_item *vn_vi;
 };
 
 /* used by directory items when creating virtual nodes */
 struct direntry_uarea {
     int flags;
     __u16 entry_count;
     __u16 entry_sizes[1];
 } __attribute__ ((__packed__));
 
 /***************************************************************************
  *                  TREE BALANCE                                           *
  ***************************************************************************/
 
 /*
  * This temporary structure is used in tree balance algorithms, and
  * constructed as we go to the extent that its various parts are
  * needed.  It contains arrays of nodes that can potentially be
  * involved in the balancing of node S, and parameters that define how
  * each of the nodes must be balanced.  Note that in these algorithms
  * for balancing the worst case is to need to balance the current node
  * S and the left and right neighbors and all of their parents plus
  * create a new node.  We implement S1 balancing for the leaf nodes
  * and S0 balancing for the internal nodes (S1 and S0 are defined in
  * our papers.)
  */
 
 /* size of the array of buffers to free at end of do_balance */
 #define MAX_FREE_BLOCK 7
 
 /* maximum number of FEB blocknrs on a single level */
 #define MAX_AMOUNT_NEEDED 2
 
 /* someday somebody will prefix every field in this struct with tb_ */
 struct tree_balance {
     int tb_mode;
     int need_balance_dirty;
     struct super_block *tb_sb;
     struct reiserfs_transaction_handle *transaction_handle;
     struct treepath *tb_path;
 
     /* array of left neighbors of nodes in the path */
     struct buffer_head *L[MAX_HEIGHT];
 
     /* array of right neighbors of nodes in the path */
     struct buffer_head *R[MAX_HEIGHT];
 
     /* array of fathers of the left neighbors */
     struct buffer_head *FL[MAX_HEIGHT];
 
     /* array of fathers of the right neighbors */
     struct buffer_head *FR[MAX_HEIGHT];
     /* array of common parents of center node and its left neighbor */
     struct buffer_head *CFL[MAX_HEIGHT];
 
     /* array of common parents of center node and its right neighbor */
     struct buffer_head *CFR[MAX_HEIGHT];
 
     /*
      * array of empty buffers. Number of buffers in array equals
      * cur_blknum.
      */
     struct buffer_head *FEB[MAX_FEB_SIZE];
     struct buffer_head *used[MAX_FEB_SIZE];
     struct buffer_head *thrown[MAX_FEB_SIZE];
 
     /*
      * array of number of items which must be shifted to the left in
      * order to balance the current node; for leaves includes item that
      * will be partially shifted; for internal nodes, it is the number
      * of child pointers rather than items. It includes the new item
      * being created. The code sometimes subtracts one to get the
      * number of wholly shifted items for other purposes.
      */
     int lnum[MAX_HEIGHT];
 
     /* substitute right for left in comment above */
     int rnum[MAX_HEIGHT];
 
     /*
      * array indexed by height h mapping the key delimiting L[h] and
      * S[h] to its item number within the node CFL[h]
      */
     int lkey[MAX_HEIGHT];
 
     /* substitute r for l in comment above */
     int rkey[MAX_HEIGHT];
 
     /*
      * the number of bytes by we are trying to add or remove from
      * S[h]. A negative value means removing.
      */
     int insert_size[MAX_HEIGHT];
 
     /*
      * number of nodes that will replace node S[h] after balancing
      * on the level h of the tree.  If 0 then S is being deleted,
      * if 1 then S is remaining and no new nodes are being created,
      * if 2 or 3 then 1 or 2 new nodes is being created
      */
     int blknum[MAX_HEIGHT];
 
     /* fields that are used only for balancing leaves of the tree */
 
     /* number of empty blocks having been already allocated */
     int cur_blknum;
 
     /* number of items that fall into left most node when S[0] splits */
     int s0num;
 
     /*
      * number of bytes which can flow to the left neighbor from the left
      * most liquid item that cannot be shifted from S[0] entirely
      * if -1 then nothing will be partially shifted
      */
     int lbytes;
 
     /*
      * number of bytes which will flow to the right neighbor from the right
      * most liquid item that cannot be shifted from S[0] entirely
      * if -1 then nothing will be partially shifted
      */
     int rbytes;
 
 
     /*
      * index into the array of item headers in
      * S[0] of the affected item
      */
     int item_pos;
 
     /* new nodes allocated to hold what could not fit into S */
     struct buffer_head *S_new[2];
 
     /*
      * number of items that will be placed into nodes in S_new
      * when S[0] splits
      */
     int snum[2];
 
     /*
      * number of bytes which flow to nodes in S_new when S[0] splits
      * note: if S[0] splits into 3 nodes, then items do not need to be cut
      */
     int sbytes[2];
 
     int pos_in_item;
     int zeroes_num;
 
     /*
      * buffers which are to be freed after do_balance finishes
      * by unfix_nodes
      */
     struct buffer_head *buf_to_free[MAX_FREE_BLOCK];
 
     /*
      * kmalloced memory. Used to create virtual node and keep
      * map of dirtied bitmap blocks
      */
     char *vn_buf;
 
     int vn_buf_size;    /* size of the vn_buf */
 
     /* VN starts after bitmap of bitmap blocks */
     struct virtual_node *tb_vn;
 
     /*
      * saved value of `reiserfs_generation' counter see
      * FILESYSTEM_CHANGED() macro in reiserfs_fs.h
      */
     int fs_gen;
 
 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
     /*
      * key pointer, to pass to block allocator or
      * another low-level subsystem
      */
     struct in_core_key key;
 #endif
 };
 
 /* These are modes of balancing */
 
 /* When inserting an item. */
 #define M_INSERT    'i'
 /*
  * When inserting into (directories only) or appending onto an already
  * existent item.
  */
 #define M_PASTE     'p'
 /* When deleting an item. */
 #define M_DELETE    'd'
 /* When truncating an item or removing an entry from a (directory) item. */
 #define M_CUT       'c'
 
 /* used when balancing on leaf level skipped (in reiserfsck) */
 #define M_INTERNAL  'n'
 
 /*
  * When further balancing is not needed, then do_balance does not need
  * to be called.
  */
 #define M_SKIP_BALANCING        's'
 #define M_CONVERT   'v'
 
 /* modes of leaf_move_items */
 #define LEAF_FROM_S_TO_L 0
 #define LEAF_FROM_S_TO_R 1
 #define LEAF_FROM_R_TO_L 2
 #define LEAF_FROM_L_TO_R 3
 #define LEAF_FROM_S_TO_SNEW 4
 
 #define FIRST_TO_LAST 0
 #define LAST_TO_FIRST 1
 
 /*
  * used in do_balance for passing parent of node information that has
  * been gotten from tb struct
  */
 struct buffer_info {
     struct tree_balance *tb;
     struct buffer_head *bi_bh;
     struct buffer_head *bi_parent;
     int bi_position;
 };
 
 static inline struct super_block *sb_from_tb(struct tree_balance *tb)
 {
     return tb ? tb->tb_sb : NULL;
 }
 
 static inline struct super_block *sb_from_bi(struct buffer_info *bi)
 {
     return bi ? sb_from_tb(bi->tb) : NULL;
 }
 
 /*
  * there are 4 types of items: stat data, directory item, indirect, direct.
  * +-------------------+------------+--------------+------------+
  * |                   |  k_offset  | k_uniqueness | mergeable? |
  * +-------------------+------------+--------------+------------+
  * |     stat data     |     0      |      0       |   no       |
  * +-------------------+------------+--------------+------------+
  * | 1st directory item| DOT_OFFSET | DIRENTRY_ .. |   no       |
  * | non 1st directory | hash value | UNIQUENESS   |   yes      |
  * |     item          |            |              |            |
  * +-------------------+------------+--------------+------------+
  * | indirect item     | offset + 1 |TYPE_INDIRECT |    [1] |
  * +-------------------+------------+--------------+------------+
  * | direct item       | offset + 1 |TYPE_DIRECT   |    [2]     |
  * +-------------------+------------+--------------+------------+
  *
  * [1] if this is not the first indirect item of the object
  * [2] if this is not the first direct item of the object
 */
 
 struct item_operations {
     int (*bytes_number) (struct item_head * ih, int block_size);
     void (*decrement_key) (struct cpu_key *);
     int (*is_left_mergeable) (struct reiserfs_key * ih,
                   unsigned long bsize);
     void (*print_item) (struct item_head *, char *item);
     void (*check_item) (struct item_head *, char *item);
 
     int (*create_vi) (struct virtual_node * vn, struct virtual_item * vi,
               int is_affected, int insert_size);
     int (*check_left) (struct virtual_item * vi, int free,
                int start_skip, int end_skip);
     int (*check_right) (struct virtual_item * vi, int free);
     int (*part_size) (struct virtual_item * vi, int from, int to);
     int (*unit_num) (struct virtual_item * vi);
     void (*print_vi) (struct virtual_item * vi);
 };
 
 extern struct item_operations *item_ops[TYPE_ANY + 1];
 
 #define op_bytes_number(ih,bsize)                    item_ops[le_ih_k_type (ih)]->bytes_number (ih, bsize)
 #define op_is_left_mergeable(key,bsize)              item_ops[le_key_k_type (le_key_version (key), key)]->is_left_mergeable (key, bsize)
 #define op_print_item(ih,item)                       item_ops[le_ih_k_type (ih)]->print_item (ih, item)
 #define op_check_item(ih,item)                       item_ops[le_ih_k_type (ih)]->check_item (ih, item)
 #define op_create_vi(vn,vi,is_affected,insert_size)  item_ops[le_ih_k_type ((vi)->vi_ih)]->create_vi (vn,vi,is_affected,insert_size)
 #define op_check_left(vi,free,start_skip,end_skip) item_ops[(vi)->vi_index]->check_left (vi, free, start_skip, end_skip)
 #define op_check_right(vi,free)                      item_ops[(vi)->vi_index]->check_right (vi, free)
 #define op_part_size(vi,from,to)                     item_ops[(vi)->vi_index]->part_size (vi, from, to)
 #define op_unit_num(vi)                  item_ops[(vi)->vi_index]->unit_num (vi)
 #define op_print_vi(vi)                              item_ops[(vi)->vi_index]->print_vi (vi)
 
 #define COMP_SHORT_KEYS comp_short_keys
 
 /* number of blocks pointed to by the indirect item */
 #define I_UNFM_NUM(ih)  (ih_item_len(ih) / UNFM_P_SIZE)
 
 /*
  * the used space within the unformatted node corresponding
  * to pos within the item pointed to by ih
  */
 #define I_POS_UNFM_SIZE(ih,pos,size) (((pos) == I_UNFM_NUM(ih) - 1 ) ? (size) - ih_free_space(ih) : (size))
 
 /*
  * number of bytes contained by the direct item or the
  * unformatted nodes the indirect item points to
  */
 
 /* following defines use reiserfs buffer header and item header */
 
 /* get stat-data */
 #define B_I_STAT_DATA(bh, ih) ( (struct stat_data * )((bh)->b_data + ih_location(ih)) )
 
 /* this is 3976 for size==4096 */
 #define MAX_DIRECT_ITEM_LEN(size) ((size) - BLKH_SIZE - 2*IH_SIZE - SD_SIZE - UNFM_P_SIZE)
 
 /*
  * indirect items consist of entries which contain blocknrs, pos
  * indicates which entry, and B_I_POS_UNFM_POINTER resolves to the
  * blocknr contained by the entry pos points to
  */
 #define B_I_POS_UNFM_POINTER(bh, ih, pos)               \
     le32_to_cpu(*(((unp_t *)ih_item_body(bh, ih)) + (pos)))
 #define PUT_B_I_POS_UNFM_POINTER(bh, ih, pos, val)          \
     (*(((unp_t *)ih_item_body(bh, ih)) + (pos)) = cpu_to_le32(val))
 
 struct reiserfs_iget_args {
     __u32 objectid;
     __u32 dirid;
 };
 
 /***************************************************************************
  *                    FUNCTION DECLARATIONS                                *
  ***************************************************************************/
 
 #define get_journal_desc_magic(bh) (bh->b_data + bh->b_size - 12)
 
 #define journal_trans_half(blocksize) \
     ((blocksize - sizeof (struct reiserfs_journal_desc) + sizeof (__u32) - 12) / sizeof (__u32))
 
 /* journal.c see journal.c for all the comments here */
 
 /* first block written in a commit.  */
 struct reiserfs_journal_desc {
     __le32 j_trans_id;  /* id of commit */
 
     /* length of commit. len +1 is the commit block */
     __le32 j_len;
 
     __le32 j_mount_id;  /* mount id of this trans */
     __le32 j_realblock[1];  /* real locations for each block */
 };
 
 #define get_desc_trans_id(d)   le32_to_cpu((d)->j_trans_id)
 #define get_desc_trans_len(d)  le32_to_cpu((d)->j_len)
 #define get_desc_mount_id(d)   le32_to_cpu((d)->j_mount_id)
 
 #define set_desc_trans_id(d,val)       do { (d)->j_trans_id = cpu_to_le32 (val); } while (0)
 #define set_desc_trans_len(d,val)      do { (d)->j_len = cpu_to_le32 (val); } while (0)
 #define set_desc_mount_id(d,val)       do { (d)->j_mount_id = cpu_to_le32 (val); } while (0)
 
 /* last block written in a commit */
 struct reiserfs_journal_commit {
     __le32 j_trans_id;  /* must match j_trans_id from the desc block */
     __le32 j_len;       /* ditto */
     __le32 j_realblock[1];  /* real locations for each block */
 };
 
 #define get_commit_trans_id(c) le32_to_cpu((c)->j_trans_id)
 #define get_commit_trans_len(c)        le32_to_cpu((c)->j_len)
 #define get_commit_mount_id(c) le32_to_cpu((c)->j_mount_id)
 
 #define set_commit_trans_id(c,val)     do { (c)->j_trans_id = cpu_to_le32 (val); } while (0)
 #define set_commit_trans_len(c,val)    do { (c)->j_len = cpu_to_le32 (val); } while (0)
 
 /*
  * this header block gets written whenever a transaction is considered
  * fully flushed, and is more recent than the last fully flushed transaction.
  * fully flushed means all the log blocks and all the real blocks are on
  * disk, and this transaction does not need to be replayed.
  */
 struct reiserfs_journal_header {
     /* id of last fully flushed transaction */
     __le32 j_last_flush_trans_id;
 
     /* offset in the log of where to start replay after a crash */
     __le32 j_first_unflushed_offset;
 
     __le32 j_mount_id;
     /* 12 */ struct journal_params jh_journal;
 };
 
 /* biggest tunable defines are right here */
 #define JOURNAL_BLOCK_COUNT 8192    /* number of blocks in the journal */
 
 /* biggest possible single transaction, don't change for now (8/3/99) */
 #define JOURNAL_TRANS_MAX_DEFAULT 1024
 #define JOURNAL_TRANS_MIN_DEFAULT 256
 
 /*
  * max blocks to batch into one transaction,
  * don't make this any bigger than 900
  */
 #define JOURNAL_MAX_BATCH_DEFAULT   900
 #define JOURNAL_MIN_RATIO 2
 #define JOURNAL_MAX_COMMIT_AGE 30
 #define JOURNAL_MAX_TRANS_AGE 30
 #define JOURNAL_PER_BALANCE_CNT (3 * (MAX_HEIGHT-2) + 9)
 #define JOURNAL_BLOCKS_PER_OBJECT(sb)  (JOURNAL_PER_BALANCE_CNT * 3 + \
                      2 * (REISERFS_QUOTA_INIT_BLOCKS(sb) + \
                           REISERFS_QUOTA_TRANS_BLOCKS(sb)))
 
 #ifdef CONFIG_QUOTA
 #define REISERFS_QUOTA_OPTS ((1 << REISERFS_USRQUOTA) | (1 << REISERFS_GRPQUOTA))
 /* We need to update data and inode (atime) */
 #define REISERFS_QUOTA_TRANS_BLOCKS(s) (REISERFS_SB(s)->s_mount_opt & REISERFS_QUOTA_OPTS ? 2 : 0)
 /* 1 balancing, 1 bitmap, 1 data per write + stat data update */
 #define REISERFS_QUOTA_INIT_BLOCKS(s) (REISERFS_SB(s)->s_mount_opt & REISERFS_QUOTA_OPTS ? \
 (DQUOT_INIT_ALLOC*(JOURNAL_PER_BALANCE_CNT+2)+DQUOT_INIT_REWRITE+1) : 0)
 /* same as with INIT */
 #define REISERFS_QUOTA_DEL_BLOCKS(s) (REISERFS_SB(s)->s_mount_opt & REISERFS_QUOTA_OPTS ? \
 (DQUOT_DEL_ALLOC*(JOURNAL_PER_BALANCE_CNT+2)+DQUOT_DEL_REWRITE+1) : 0)
 #else
 #define REISERFS_QUOTA_TRANS_BLOCKS(s) 0
 #define REISERFS_QUOTA_INIT_BLOCKS(s) 0
 #define REISERFS_QUOTA_DEL_BLOCKS(s) 0
 #endif
 
 /*
  * both of these can be as low as 1, or as high as you want.  The min is the
  * number of 4k bitmap nodes preallocated on mount. New nodes are allocated
  * as needed, and released when transactions are committed.  On release, if
  * the current number of nodes is > max, the node is freed, otherwise,
  * it is put on a free list for faster use later.
 */
 #define REISERFS_MIN_BITMAP_NODES 10
 #define REISERFS_MAX_BITMAP_NODES 100
 
 /* these are based on journal hash size of 8192 */
 #define JBH_HASH_SHIFT 13
 #define JBH_HASH_MASK 8191
 
 #define _jhashfn(sb,block)  \
     (((unsigned long)sb>>L1_CACHE_SHIFT) ^ \
      (((block)<<(JBH_HASH_SHIFT - 6)) ^ ((block) >> 13) ^ ((block) << (JBH_HASH_SHIFT - 12))))
 #define journal_hash(t,sb,block) ((t)[_jhashfn((sb),(block)) & JBH_HASH_MASK])
 
 /* We need these to make journal.c code more readable */
 #define journal_find_get_block(s, block) __find_get_block(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
 #define journal_getblk(s, block) __getblk(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
 #define journal_bread(s, block) __bread(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
 
 enum reiserfs_bh_state_bits {
     BH_JDirty = BH_PrivateStart,    /* buffer is in current transaction */
     BH_JDirty_wait,
     /*
      * disk block was taken off free list before being in a
      * finished transaction, or written to disk. Can be reused immed.
      */
     BH_JNew,
     BH_JPrepared,
     BH_JRestore_dirty,
     BH_JTest,       /* debugging only will go away */
 };
 
 BUFFER_FNS(JDirty, journaled);
 TAS_BUFFER_FNS(JDirty, journaled);
 BUFFER_FNS(JDirty_wait, journal_dirty);
 TAS_BUFFER_FNS(JDirty_wait, journal_dirty);
 BUFFER_FNS(JNew, journal_new);
 TAS_BUFFER_FNS(JNew, journal_new);
 BUFFER_FNS(JPrepared, journal_prepared);
 TAS_BUFFER_FNS(JPrepared, journal_prepared);
 BUFFER_FNS(JRestore_dirty, journal_restore_dirty);
 TAS_BUFFER_FNS(JRestore_dirty, journal_restore_dirty);
 BUFFER_FNS(JTest, journal_test);
 TAS_BUFFER_FNS(JTest, journal_test);
 
 /* transaction handle which is passed around for all journal calls */
 struct reiserfs_transaction_handle {
     /*
      * super for this FS when journal_begin was called. saves calls to
      * reiserfs_get_super also used by nested transactions to make
      * sure they are nesting on the right FS _must_ be first
      * in the handle
      */
     struct super_block *t_super;
 
     int t_refcount;
     int t_blocks_logged;    /* number of blocks this writer has logged */
     int t_blocks_allocated; /* number of blocks this writer allocated */
 
     /* sanity check, equals the current trans id */
     unsigned int t_trans_id;
 
     void *t_handle_save;    /* save existing current->journal_info */
 
     /*
      * if new block allocation occurres, that block
      * should be displaced from others
      */
     unsigned displace_new_blocks:1;
 
     struct list_head t_list;
 };
 
 /*
  * used to keep track of ordered and tail writes, attached to the buffer
  * head through b_journal_head.
  */
 struct reiserfs_jh {
     struct reiserfs_journal_list *jl;
     struct buffer_head *bh;
     struct list_head list;
 };
 
 void reiserfs_free_jh(struct buffer_head *bh);
 int reiserfs_add_tail_list(struct inode *inode, struct buffer_head *bh);
 int reiserfs_add_ordered_list(struct inode *inode, struct buffer_head *bh);
 int journal_mark_dirty(struct reiserfs_transaction_handle *,
                struct buffer_head *bh);
 
 static inline int reiserfs_file_data_log(struct inode *inode)
 {
     if (reiserfs_data_log(inode->i_sb) ||
         (REISERFS_I(inode)->i_flags & i_data_log))
         return 1;
     return 0;
 }
 
 static inline int reiserfs_transaction_running(struct super_block *s)
 {
     struct reiserfs_transaction_handle *th = current->journal_info;
     if (th && th->t_super == s)
         return 1;
     if (th && th->t_super == NULL)
         BUG();
     return 0;
 }
 
 static inline int reiserfs_transaction_free_space(struct reiserfs_transaction_handle *th)
 {
     return th->t_blocks_allocated - th->t_blocks_logged;
 }
 
 struct reiserfs_transaction_handle *reiserfs_persistent_transaction(struct
                                     super_block
                                     *,
                                     int count);
 int reiserfs_end_persistent_transaction(struct reiserfs_transaction_handle *);
 void reiserfs_vfs_truncate_file(struct inode *inode);
 int reiserfs_commit_page(struct inode *inode, struct page *page,
              unsigned from, unsigned to);
 void reiserfs_flush_old_commits(struct super_block *);
 int reiserfs_commit_for_inode(struct inode *);
 int reiserfs_inode_needs_commit(struct inode *);
 void reiserfs_update_inode_transaction(struct inode *);
 void reiserfs_wait_on_write_block(struct super_block *s);
 void reiserfs_block_writes(struct reiserfs_transaction_handle *th);
 void reiserfs_allow_writes(struct super_block *s);
 void reiserfs_check_lock_depth(struct super_block *s, char *caller);
 int reiserfs_prepare_for_journal(struct super_block *, struct buffer_head *bh,
                  int wait);
 void reiserfs_restore_prepared_buffer(struct super_block *,
                       struct buffer_head *bh);
 int journal_init(struct super_block *, const char *j_dev_name, int old_format,
          unsigned int);
 int journal_release(struct reiserfs_transaction_handle *, struct super_block *);
 int journal_release_error(struct reiserfs_transaction_handle *,
               struct super_block *);
 int journal_end(struct reiserfs_transaction_handle *);
 int journal_end_sync(struct reiserfs_transaction_handle *);
 int journal_mark_freed(struct reiserfs_transaction_handle *,
                struct super_block *, b_blocknr_t blocknr);
 int journal_transaction_should_end(struct reiserfs_transaction_handle *, int);
 int reiserfs_in_journal(struct super_block *sb, unsigned int bmap_nr,
              int bit_nr, int searchall, b_blocknr_t *next);
 int journal_begin(struct reiserfs_transaction_handle *,
           struct super_block *sb, unsigned long);
 int journal_join_abort(struct reiserfs_transaction_handle *,
                struct super_block *sb);
 void reiserfs_abort_journal(struct super_block *sb, int errno);
 void reiserfs_abort(struct super_block *sb, int errno, const char *fmt, ...);
 int reiserfs_allocate_list_bitmaps(struct super_block *s,
                    struct reiserfs_list_bitmap *, unsigned int);
 
 void reiserfs_schedule_old_flush(struct super_block *s);
 void reiserfs_cancel_old_flush(struct super_block *s);
 void add_save_link(struct reiserfs_transaction_handle *th,
            struct inode *inode, int truncate);
 int remove_save_link(struct inode *inode, int truncate);
 
 /* objectid.c */
 __u32 reiserfs_get_unused_objectid(struct reiserfs_transaction_handle *th);
 void reiserfs_release_objectid(struct reiserfs_transaction_handle *th,
                    __u32 objectid_to_release);
 int reiserfs_convert_objectid_map_v1(struct super_block *);
 
 /* stree.c */
 int B_IS_IN_TREE(const struct buffer_head *);
 extern void copy_item_head(struct item_head *to,
                const struct item_head *from);
 
 /* first key is in cpu form, second - le */
 extern int comp_short_keys(const struct reiserfs_key *le_key,
                const struct cpu_key *cpu_key);
 extern void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from);
 
 /* both are in le form */
 extern int comp_le_keys(const struct reiserfs_key *,
             const struct reiserfs_key *);
 extern int comp_short_le_keys(const struct reiserfs_key *,
                   const struct reiserfs_key *);
 
 /* * get key version from on disk key - kludge */
 static inline int le_key_version(const struct reiserfs_key *key)
 {
     int type;
 
     type = offset_v2_k_type(&(key->u.k_offset_v2));
     if (type != TYPE_DIRECT && type != TYPE_INDIRECT
         && type != TYPE_DIRENTRY)
         return KEY_FORMAT_3_5;
 
     return KEY_FORMAT_3_6;
 
 }
 
 static inline void copy_key(struct reiserfs_key *to,
                 const struct reiserfs_key *from)
 {
     memcpy(to, from, KEY_SIZE);
 }
 
 int comp_items(const struct item_head *stored_ih, const struct treepath *path);
 const struct reiserfs_key *get_rkey(const struct treepath *chk_path,
                     const struct super_block *sb);
 int search_by_key(struct super_block *, const struct cpu_key *,
           struct treepath *, int);
 #define search_item(s,key,path) search_by_key (s, key, path, DISK_LEAF_NODE_LEVEL)
 int search_for_position_by_key(struct super_block *sb,
                    const struct cpu_key *cpu_key,
                    struct treepath *search_path);
 extern void decrement_bcount(struct buffer_head *bh);
 void decrement_counters_in_path(struct treepath *search_path);
 void pathrelse(struct treepath *search_path);
 int reiserfs_check_path(struct treepath *p);
 void pathrelse_and_restore(struct super_block *s, struct treepath *search_path);
 
 int reiserfs_insert_item(struct reiserfs_transaction_handle *th,
              struct treepath *path,
              const struct cpu_key *key,
              struct item_head *ih,
              struct inode *inode, const char *body);
 
 int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th,
                  struct treepath *path,
                  const struct cpu_key *key,
                  struct inode *inode,
                  const char *body, int paste_size);
 
 int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th,
                struct treepath *path,
                struct cpu_key *key,
                struct inode *inode,
                struct page *page, loff_t new_file_size);
 
 int reiserfs_delete_item(struct reiserfs_transaction_handle *th,
              struct treepath *path,
              const struct cpu_key *key,
              struct inode *inode, struct buffer_head *un_bh);
 
 void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th,
                 struct inode *inode, struct reiserfs_key *key);
 int reiserfs_delete_object(struct reiserfs_transaction_handle *th,
                struct inode *inode);
 int reiserfs_do_truncate(struct reiserfs_transaction_handle *th,
              struct inode *inode, struct page *,
              int update_timestamps);
 
 #define i_block_size(inode) ((inode)->i_sb->s_blocksize)
 #define file_size(inode) ((inode)->i_size)
 #define tail_size(inode) (file_size (inode) & (i_block_size (inode) - 1))
 
 #define tail_has_to_be_packed(inode) (have_large_tails ((inode)->i_sb)?\
 !STORE_TAIL_IN_UNFM_S1(file_size (inode), tail_size(inode), inode->i_sb->s_blocksize):have_small_tails ((inode)->i_sb)?!STORE_TAIL_IN_UNFM_S2(file_size (inode), tail_size(inode), inode->i_sb->s_blocksize):0 )
 
 void padd_item(char *item, int total_length, int length);
 
 /* inode.c */
 /* args for the create parameter of reiserfs_get_block */
 #define GET_BLOCK_NO_CREATE 0    /* don't create new blocks or convert tails */
 #define GET_BLOCK_CREATE 1   /* add anything you need to find block */
 #define GET_BLOCK_NO_HOLE 2  /* return -ENOENT for file holes */
 #define GET_BLOCK_READ_DIRECT 4  /* read the tail if indirect item not found */
 #define GET_BLOCK_NO_IMUX     8  /* i_mutex is not held, don't preallocate */
 #define GET_BLOCK_NO_DANGLE   16 /* don't leave any transactions running */
 
 void reiserfs_read_locked_inode(struct inode *inode,
                 struct reiserfs_iget_args *args);
 int reiserfs_find_actor(struct inode *inode, void *p);
 int reiserfs_init_locked_inode(struct inode *inode, void *p);
 void reiserfs_evict_inode(struct inode *inode);
 int reiserfs_write_inode(struct inode *inode, struct writeback_control *wbc);
 int reiserfs_get_block(struct inode *inode, sector_t block,
                struct buffer_head *bh_result, int create);
 struct dentry *reiserfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
                      int fh_len, int fh_type);
 struct dentry *reiserfs_fh_to_parent(struct super_block *sb, struct fid *fid,
                      int fh_len, int fh_type);
 int reiserfs_encode_fh(struct inode *inode, __u32 * data, int *lenp,
                struct inode *parent);
 
 int reiserfs_truncate_file(struct inode *, int update_timestamps);
 void make_cpu_key(struct cpu_key *cpu_key, struct inode *inode, loff_t offset,
           int type, int key_length);
 void make_le_item_head(struct item_head *ih, const struct cpu_key *key,
                int version,
                loff_t offset, int type, int length, int entry_count);
 struct inode *reiserfs_iget(struct super_block *s, const struct cpu_key *key);
 
 struct reiserfs_security_handle;
 int reiserfs_new_inode(struct reiserfs_transaction_handle *th,
                struct inode *dir, umode_t mode,
                const char *symname, loff_t i_size,
                struct dentry *dentry, struct inode *inode,
                struct reiserfs_security_handle *security);
 
 void reiserfs_update_sd_size(struct reiserfs_transaction_handle *th,
                  struct inode *inode, loff_t size);
 
 static inline void reiserfs_update_sd(struct reiserfs_transaction_handle *th,
                       struct inode *inode)
 {
     reiserfs_update_sd_size(th, inode, inode->i_size);
 }
 
 void sd_attrs_to_i_attrs(__u16 sd_attrs, struct inode *inode);
 int reiserfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
              struct iattr *attr);
 
 int __reiserfs_write_begin(struct page *page, unsigned from, unsigned len);
 
 /* namei.c */
 void set_de_name_and_namelen(struct reiserfs_dir_entry *de);
 int search_by_entry_key(struct super_block *sb, const struct cpu_key *key,
             struct treepath *path, struct reiserfs_dir_entry *de);
 struct dentry *reiserfs_get_parent(struct dentry *);
 
 #ifdef CONFIG_REISERFS_PROC_INFO
 int reiserfs_proc_info_init(struct super_block *sb);
 int reiserfs_proc_info_done(struct super_block *sb);
 int reiserfs_proc_info_global_init(void);
 int reiserfs_proc_info_global_done(void);
 
 #define PROC_EXP( e )   e
 
 #define __PINFO( sb ) REISERFS_SB(sb) -> s_proc_info_data
 #define PROC_INFO_MAX( sb, field, value )                               \
     __PINFO( sb ).field =                                               \
         max( REISERFS_SB( sb ) -> s_proc_info_data.field, value )
 #define PROC_INFO_INC( sb, field ) ( ++ ( __PINFO( sb ).field ) )
 #define PROC_INFO_ADD( sb, field, val ) ( __PINFO( sb ).field += ( val ) )
 #define PROC_INFO_BH_STAT( sb, bh, level )                          \
     PROC_INFO_INC( sb, sbk_read_at[ ( level ) ] );                      \
     PROC_INFO_ADD( sb, free_at[ ( level ) ], B_FREE_SPACE( bh ) );  \
     PROC_INFO_ADD( sb, items_at[ ( level ) ], B_NR_ITEMS( bh ) )
 #else
 static inline int reiserfs_proc_info_init(struct super_block *sb)
 {
     return 0;
 }
 
 static inline int reiserfs_proc_info_done(struct super_block *sb)
 {
     return 0;
 }
 
 static inline int reiserfs_proc_info_global_init(void)
 {
     return 0;
 }
 
 static inline int reiserfs_proc_info_global_done(void)
 {
     return 0;
 }
 
 #define PROC_EXP( e )
 #define VOID_V ( ( void ) 0 )
 #define PROC_INFO_MAX( sb, field, value ) VOID_V
 #define PROC_INFO_INC( sb, field ) VOID_V
 #define PROC_INFO_ADD( sb, field, val ) VOID_V
 #define PROC_INFO_BH_STAT(sb, bh, n_node_level) VOID_V
 #endif
 
 /* dir.c */
 extern const struct inode_operations reiserfs_dir_inode_operations;
 extern const struct inode_operations reiserfs_symlink_inode_operations;
 extern const struct inode_operations reiserfs_special_inode_operations;
 extern const struct file_operations reiserfs_dir_operations;
 int reiserfs_readdir_inode(struct inode *, struct dir_context *);
 
 /* tail_conversion.c */
 int direct2indirect(struct reiserfs_transaction_handle *, struct inode *,
             struct treepath *, struct buffer_head *, loff_t);
 int indirect2direct(struct reiserfs_transaction_handle *, struct inode *,
             struct page *, struct treepath *, const struct cpu_key *,
             loff_t, char *);
 void reiserfs_unmap_buffer(struct buffer_head *);
 
 /* file.c */
 extern const struct inode_operations reiserfs_file_inode_operations;
 extern const struct file_operations reiserfs_file_operations;
 extern const struct address_space_operations reiserfs_address_space_operations;
 
 /* fix_nodes.c */
 
 int fix_nodes(int n_op_mode, struct tree_balance *tb,
           struct item_head *ins_ih, const void *);
 void unfix_nodes(struct tree_balance *);
 
 /* prints.c */
 void __reiserfs_panic(struct super_block *s, const char *id,
               const char *function, const char *fmt, ...)
     __attribute__ ((noreturn));
 #define reiserfs_panic(s, id, fmt, args...) \
     __reiserfs_panic(s, id, __func__, fmt, ##args)
 void __reiserfs_error(struct super_block *s, const char *id,
               const char *function, const char *fmt, ...);
 #define reiserfs_error(s, id, fmt, args...) \
      __reiserfs_error(s, id, __func__, fmt, ##args)
 void reiserfs_info(struct super_block *s, const char *fmt, ...);
 void reiserfs_debug(struct super_block *s, int level, const char *fmt, ...);
 void print_indirect_item(struct buffer_head *bh, int item_num);
 void store_print_tb(struct tree_balance *tb);
 void print_cur_tb(char *mes);
 void print_de(struct reiserfs_dir_entry *de);
 void print_bi(struct buffer_info *bi, char *mes);
 #define PRINT_LEAF_ITEMS 1  /* print all items */
 #define PRINT_DIRECTORY_ITEMS 2 /* print directory items */
 #define PRINT_DIRECT_ITEMS 4    /* print contents of direct items */
 void print_block(struct buffer_head *bh, ...);
 void print_bmap(struct super_block *s, int silent);
 void print_bmap_block(int i, char *data, int size, int silent);
 /*void print_super_block (struct super_block * s, char * mes);*/
 void print_objectid_map(struct super_block *s);
 void print_block_head(struct buffer_head *bh, char *mes);
 void check_leaf(struct buffer_head *bh);
 void check_internal(struct buffer_head *bh);
 void print_statistics(struct super_block *s);
 char *reiserfs_hashname(int code);
 
 /* lbalance.c */
 int leaf_move_items(int shift_mode, struct tree_balance *tb, int mov_num,
             int mov_bytes, struct buffer_head *Snew);
 int leaf_shift_left(struct tree_balance *tb, int shift_num, int shift_bytes);
 int leaf_shift_right(struct tree_balance *tb, int shift_num, int shift_bytes);
 void leaf_delete_items(struct buffer_info *cur_bi, int last_first, int first,
                int del_num, int del_bytes);
 void leaf_insert_into_buf(struct buffer_info *bi, int before,
               struct item_head * const inserted_item_ih,
               const char * const inserted_item_body,
               int zeros_number);
 void leaf_paste_in_buffer(struct buffer_info *bi, int pasted_item_num,
               int pos_in_item, int paste_size,
               const char * const body, int zeros_number);
 void leaf_cut_from_buffer(struct buffer_info *bi, int cut_item_num,
               int pos_in_item, int cut_size);
 void leaf_paste_entries(struct buffer_info *bi, int item_num, int before,
             int new_entry_count, struct reiserfs_de_head *new_dehs,
             const char *records, int paste_size);
 /* ibalance.c */
 int balance_internal(struct tree_balance *, int, int, struct item_head *,
              struct buffer_head **);
 
 /* do_balance.c */
 void do_balance_mark_leaf_dirty(struct tree_balance *tb,
                 struct buffer_head *bh, int flag);
 #define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty
 #define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty
 
 void do_balance(struct tree_balance *tb, struct item_head *ih,
         const char *body, int flag);
 void reiserfs_invalidate_buffer(struct tree_balance *tb,
                 struct buffer_head *bh);
 
 int get_left_neighbor_position(struct tree_balance *tb, int h);
 int get_right_neighbor_position(struct tree_balance *tb, int h);
 void replace_key(struct tree_balance *tb, struct buffer_head *, int,
          struct buffer_head *, int);
 void make_empty_node(struct buffer_info *);
 struct buffer_head *get_FEB(struct tree_balance *);
 
 /* bitmap.c */
 
 /*
  * structure contains hints for block allocator, and it is a container for
  * arguments, such as node, search path, transaction_handle, etc.
  */
 struct __reiserfs_blocknr_hint {
     /* inode passed to allocator, if we allocate unf. nodes */
     struct inode *inode;
 
     sector_t block;     /* file offset, in blocks */
     struct in_core_key key;
 
     /*
      * search path, used by allocator to deternine search_start by
      * various ways
      */
     struct treepath *path;
 
     /*
      * transaction handle is needed to log super blocks
      * and bitmap blocks changes
      */
     struct reiserfs_transaction_handle *th;
 
     b_blocknr_t beg, end;
 
     /*
      * a field used to transfer search start value (block number)
      * between different block allocator procedures
      * (determine_search_start() and others)
      */
     b_blocknr_t search_start;
 
     /*
      * is set in determine_prealloc_size() function,
      * used by underlayed function that do actual allocation
      */
     int prealloc_size;
 
     /*
      * the allocator uses different polices for getting disk
      * space for formatted/unformatted blocks with/without preallocation
      */
     unsigned formatted_node:1;
     unsigned preallocate:1;
 };
 
 typedef struct __reiserfs_blocknr_hint reiserfs_blocknr_hint_t;
 
 int reiserfs_parse_alloc_options(struct super_block *, char *);
 void reiserfs_init_alloc_options(struct super_block *s);
 
 /*
  * given a directory, this will tell you what packing locality
  * to use for a new object underneat it.  The locality is returned
  * in disk byte order (le).
  */
 __le32 reiserfs_choose_packing(struct inode *dir);
 
 void show_alloc_options(struct seq_file *seq, struct super_block *s);
 int reiserfs_init_bitmap_cache(struct super_block *sb);
 void reiserfs_free_bitmap_cache(struct super_block *sb);
 void reiserfs_cache_bitmap_metadata(struct super_block *sb, struct buffer_head *bh, struct reiserfs_bitmap_info *info);
 struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb, unsigned int bitmap);
 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
 void reiserfs_free_block(struct reiserfs_transaction_handle *th, struct inode *,
              b_blocknr_t, int for_unformatted);
 int reiserfs_allocate_blocknrs(reiserfs_blocknr_hint_t *, b_blocknr_t *, int,
                    int);
 static inline int reiserfs_new_form_blocknrs(struct tree_balance *tb,
                          b_blocknr_t * new_blocknrs,
                          int amount_needed)
 {
     reiserfs_blocknr_hint_t hint = {
         .th = tb->transaction_handle,
         .path = tb->tb_path,
         .inode = NULL,
         .key = tb->key,
         .block = 0,
         .formatted_node = 1
     };
     return reiserfs_allocate_blocknrs(&hint, new_blocknrs, amount_needed,
                       0);
 }
 
 static inline int reiserfs_new_unf_blocknrs(struct reiserfs_transaction_handle
                         *th, struct inode *inode,
                         b_blocknr_t * new_blocknrs,
                         struct treepath *path,
                         sector_t block)
 {
     reiserfs_blocknr_hint_t hint = {
         .th = th,
         .path = path,
         .inode = inode,
         .block = block,
         .formatted_node = 0,
         .preallocate = 0
     };
     return reiserfs_allocate_blocknrs(&hint, new_blocknrs, 1, 0);
 }
 
 #ifdef REISERFS_PREALLOCATE
 static inline int reiserfs_new_unf_blocknrs2(struct reiserfs_transaction_handle
                          *th, struct inode *inode,
                          b_blocknr_t * new_blocknrs,
                          struct treepath *path,
                          sector_t block)
 {
     reiserfs_blocknr_hint_t hint = {
         .th = th,
         .path = path,
         .inode = inode,
         .block = block,
         .formatted_node = 0,
         .preallocate = 1
     };
     return reiserfs_allocate_blocknrs(&hint, new_blocknrs, 1, 0);
 }
 
 void reiserfs_discard_prealloc(struct reiserfs_transaction_handle *th,
                    struct inode *inode);
 void reiserfs_discard_all_prealloc(struct reiserfs_transaction_handle *th);
 #endif
 
 /* hashes.c */
 __u32 keyed_hash(const signed char *msg, int len);
 __u32 yura_hash(const signed char *msg, int len);
 __u32 r5_hash(const signed char *msg, int len);
 
 #define reiserfs_set_le_bit     __set_bit_le
 #define reiserfs_test_and_set_le_bit    __test_and_set_bit_le
 #define reiserfs_clear_le_bit       __clear_bit_le
 #define reiserfs_test_and_clear_le_bit  __test_and_clear_bit_le
 #define reiserfs_test_le_bit        test_bit_le
 #define reiserfs_find_next_zero_le_bit  find_next_zero_bit_le
 
 /*
  * sometimes reiserfs_truncate may require to allocate few new blocks
  * to perform indirect2direct conversion. People probably used to
  * think, that truncate should work without problems on a filesystem
  * without free disk space. They may complain that they can not
  * truncate due to lack of free disk space. This spare space allows us
  * to not worry about it. 500 is probably too much, but it should be
  * absolutely safe
  */
 #define SPARE_SPACE 500
 
 /* prototypes from ioctl.c */
 int reiserfs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
 int reiserfs_fileattr_set(struct user_namespace *mnt_userns,
               struct dentry *dentry, struct fileattr *fa);
 long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
 long reiserfs_compat_ioctl(struct file *filp,
            unsigned int cmd, unsigned long arg);
 int reiserfs_unpack(struct inode *inode);