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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
 /*
  *  fs/ext4/extents_status.c
  *
  * Written by Yongqiang Yang <xiaoqiangnk@gmail.com>
  * Modified by
  *  Allison Henderson <achender@linux.vnet.ibm.com>
  *  Hugh Dickins <hughd@google.com>
  *  Zheng Liu <wenqing.lz@taobao.com>
  *
  * Ext4 extents status tree core functions.
  */
 #include <linux/list_sort.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include "ext4.h"
 
 #include <trace/events/ext4.h>
 
 /*
  * According to previous discussion in Ext4 Developer Workshop, we
  * will introduce a new structure called io tree to track all extent
  * status in order to solve some problems that we have met
  * (e.g. Reservation space warning), and provide extent-level locking.
  * Delay extent tree is the first step to achieve this goal.  It is
  * original built by Yongqiang Yang.  At that time it is called delay
  * extent tree, whose goal is only track delayed extents in memory to
  * simplify the implementation of fiemap and bigalloc, and introduce
  * lseek SEEK_DATA/SEEK_HOLE support.  That is why it is still called
  * delay extent tree at the first commit.  But for better understand
  * what it does, it has been rename to extent status tree.
  *
  * Step1:
  * Currently the first step has been done.  All delayed extents are
  * tracked in the tree.  It maintains the delayed extent when a delayed
  * allocation is issued, and the delayed extent is written out or
  * invalidated.  Therefore the implementation of fiemap and bigalloc
  * are simplified, and SEEK_DATA/SEEK_HOLE are introduced.
  *
  * The following comment describes the implemenmtation of extent
  * status tree and future works.
  *
  * Step2:
  * In this step all extent status are tracked by extent status tree.
  * Thus, we can first try to lookup a block mapping in this tree before
  * finding it in extent tree.  Hence, single extent cache can be removed
  * because extent status tree can do a better job.  Extents in status
  * tree are loaded on-demand.  Therefore, the extent status tree may not
  * contain all of the extents in a file.  Meanwhile we define a shrinker
  * to reclaim memory from extent status tree because fragmented extent
  * tree will make status tree cost too much memory.  written/unwritten/-
  * hole extents in the tree will be reclaimed by this shrinker when we
  * are under high memory pressure.  Delayed extents will not be
  * reclimed because fiemap, bigalloc, and seek_data/hole need it.
  */
 
 /*
  * Extent status tree implementation for ext4.
  *
  *
  * ==========================================================================
  * Extent status tree tracks all extent status.
  *
  * 1. Why we need to implement extent status tree?
  *
  * Without extent status tree, ext4 identifies a delayed extent by looking
  * up page cache, this has several deficiencies - complicated, buggy,
  * and inefficient code.
  *
  * FIEMAP, SEEK_HOLE/DATA, bigalloc, and writeout all need to know if a
  * block or a range of blocks are belonged to a delayed extent.
  *
  * Let us have a look at how they do without extent status tree.
  *   -- FIEMAP
  *  FIEMAP looks up page cache to identify delayed allocations from holes.
  *
  *   -- SEEK_HOLE/DATA
  *  SEEK_HOLE/DATA has the same problem as FIEMAP.
  *
  *   -- bigalloc
  *  bigalloc looks up page cache to figure out if a block is
  *  already under delayed allocation or not to determine whether
  *  quota reserving is needed for the cluster.
  *
  *   -- writeout
  *  Writeout looks up whole page cache to see if a buffer is
  *  mapped, If there are not very many delayed buffers, then it is
  *  time consuming.
  *
  * With extent status tree implementation, FIEMAP, SEEK_HOLE/DATA,
  * bigalloc and writeout can figure out if a block or a range of
  * blocks is under delayed allocation(belonged to a delayed extent) or
  * not by searching the extent tree.
  *
  *
  * ==========================================================================
  * 2. Ext4 extent status tree impelmentation
  *
  *   -- extent
  *  A extent is a range of blocks which are contiguous logically and
  *  physically.  Unlike extent in extent tree, this extent in ext4 is
  *  a in-memory struct, there is no corresponding on-disk data.  There
  *  is no limit on length of extent, so an extent can contain as many
  *  blocks as they are contiguous logically and physically.
  *
  *   -- extent status tree
  *  Every inode has an extent status tree and all allocation blocks
  *  are added to the tree with different status.  The extent in the
  *  tree are ordered by logical block no.
  *
  *   -- operations on a extent status tree
  *  There are three important operations on a delayed extent tree: find
  *  next extent, adding a extent(a range of blocks) and removing a extent.
  *
  *   -- race on a extent status tree
  *  Extent status tree is protected by inode->i_es_lock.
  *
  *   -- memory consumption
  *      Fragmented extent tree will make extent status tree cost too much
  *      memory.  Hence, we will reclaim written/unwritten/hole extents from
  *      the tree under a heavy memory pressure.
  *
  *
  * ==========================================================================
  * 3. Performance analysis
  *
  *   -- overhead
  *  1. There is a cache extent for write access, so if writes are
  *  not very random, adding space operaions are in O(1) time.
  *
  *   -- gain
  *  2. Code is much simpler, more readable, more maintainable and
  *  more efficient.
  *
  *
  * ==========================================================================
  * 4. TODO list
  *
  *   -- Refactor delayed space reservation
  *
  *   -- Extent-level locking
  */
 
 static struct kmem_cache *ext4_es_cachep;
 static struct kmem_cache *ext4_pending_cachep;
 
 static int __es_insert_extent(struct inode *inode, struct extent_status *newes);
 static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                   ext4_lblk_t end, int *reserved);
 static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan);
 static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
                struct ext4_inode_info *locked_ei);
 static void __revise_pending(struct inode *inode, ext4_lblk_t lblk,
                  ext4_lblk_t len);
 
 int __init ext4_init_es(void)
 {
     ext4_es_cachep = kmem_cache_create("ext4_extent_status",
                        sizeof(struct extent_status),
                        0, (SLAB_RECLAIM_ACCOUNT), NULL);
     if (ext4_es_cachep == NULL)
         return -ENOMEM;
     return 0;
 }
 
 void ext4_exit_es(void)
 {
     kmem_cache_destroy(ext4_es_cachep);
 }
 
 void ext4_es_init_tree(struct ext4_es_tree *tree)
 {
     tree->root = RB_ROOT;
     tree->cache_es = NULL;
 }
 
 #ifdef ES_DEBUG__
 static void ext4_es_print_tree(struct inode *inode)
 {
     struct ext4_es_tree *tree;
     struct rb_node *node;
 
     printk(KERN_DEBUG "status extents for inode %lu:", inode->i_ino);
     tree = &EXT4_I(inode)->i_es_tree;
     node = rb_first(&tree->root);
     while (node) {
         struct extent_status *es;
         es = rb_entry(node, struct extent_status, rb_node);
         printk(KERN_DEBUG " [%u/%u) %llu %x",
                es->es_lblk, es->es_len,
                ext4_es_pblock(es), ext4_es_status(es));
         node = rb_next(node);
     }
     printk(KERN_DEBUG "\n");
 }
 #else
 #define ext4_es_print_tree(inode)
 #endif
 
 static inline ext4_lblk_t ext4_es_end(struct extent_status *es)
 {
     BUG_ON(es->es_lblk + es->es_len < es->es_lblk);
     return es->es_lblk + es->es_len - 1;
 }
 
 /*
  * search through the tree for an delayed extent with a given offset.  If
  * it can't be found, try to find next extent.
  */
 static struct extent_status *__es_tree_search(struct rb_root *root,
                           ext4_lblk_t lblk)
 {
     struct rb_node *node = root->rb_node;
     struct extent_status *es = NULL;
 
     while (node) {
         es = rb_entry(node, struct extent_status, rb_node);
         if (lblk < es->es_lblk)
             node = node->rb_left;
         else if (lblk > ext4_es_end(es))
             node = node->rb_right;
         else
             return es;
     }
 
     if (es && lblk < es->es_lblk)
         return es;
 
     if (es && lblk > ext4_es_end(es)) {
         node = rb_next(&es->rb_node);
         return node ? rb_entry(node, struct extent_status, rb_node) :
                   NULL;
     }
 
     return NULL;
 }
 
 /*
  * ext4_es_find_extent_range - find extent with specified status within block
  *                             range or next extent following block range in
  *                             extents status tree
  *
  * @inode - file containing the range
  * @matching_fn - pointer to function that matches extents with desired status
  * @lblk - logical block defining start of range
  * @end - logical block defining end of range
  * @es - extent found, if any
  *
  * Find the first extent within the block range specified by @lblk and @end
  * in the extents status tree that satisfies @matching_fn.  If a match
  * is found, it's returned in @es.  If not, and a matching extent is found
  * beyond the block range, it's returned in @es.  If no match is found, an
  * extent is returned in @es whose es_lblk, es_len, and es_pblk components
  * are 0.
  */
 static void __es_find_extent_range(struct inode *inode,
                    int (*matching_fn)(struct extent_status *es),
                    ext4_lblk_t lblk, ext4_lblk_t end,
                    struct extent_status *es)
 {
     struct ext4_es_tree *tree = NULL;
     struct extent_status *es1 = NULL;
     struct rb_node *node;
 
     WARN_ON(es == NULL);
     WARN_ON(end < lblk);
 
     tree = &EXT4_I(inode)->i_es_tree;
 
     /* see if the extent has been cached */
     es->es_lblk = es->es_len = es->es_pblk = 0;
     if (tree->cache_es) {
         es1 = tree->cache_es;
         if (in_range(lblk, es1->es_lblk, es1->es_len)) {
             es_debug("%u cached by [%u/%u) %llu %x\n",
                  lblk, es1->es_lblk, es1->es_len,
                  ext4_es_pblock(es1), ext4_es_status(es1));
             goto out;
         }
     }
 
     es1 = __es_tree_search(&tree->root, lblk);
 
 out:
     if (es1 && !matching_fn(es1)) {
         while ((node = rb_next(&es1->rb_node)) != NULL) {
             es1 = rb_entry(node, struct extent_status, rb_node);
             if (es1->es_lblk > end) {
                 es1 = NULL;
                 break;
             }
             if (matching_fn(es1))
                 break;
         }
     }
 
     if (es1 && matching_fn(es1)) {
         tree->cache_es = es1;
         es->es_lblk = es1->es_lblk;
         es->es_len = es1->es_len;
         es->es_pblk = es1->es_pblk;
     }
 
 }
 
 /*
  * Locking for __es_find_extent_range() for external use
  */
 void ext4_es_find_extent_range(struct inode *inode,
                    int (*matching_fn)(struct extent_status *es),
                    ext4_lblk_t lblk, ext4_lblk_t end,
                    struct extent_status *es)
 {
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return;
 
     trace_ext4_es_find_extent_range_enter(inode, lblk);
 
     read_lock(&EXT4_I(inode)->i_es_lock);
     __es_find_extent_range(inode, matching_fn, lblk, end, es);
     read_unlock(&EXT4_I(inode)->i_es_lock);
 
     trace_ext4_es_find_extent_range_exit(inode, es);
 }
 
 /*
  * __es_scan_range - search block range for block with specified status
  *                   in extents status tree
  *
  * @inode - file containing the range
  * @matching_fn - pointer to function that matches extents with desired status
  * @lblk - logical block defining start of range
  * @end - logical block defining end of range
  *
  * Returns true if at least one block in the specified block range satisfies
  * the criterion specified by @matching_fn, and false if not.  If at least
  * one extent has the specified status, then there is at least one block
  * in the cluster with that status.  Should only be called by code that has
  * taken i_es_lock.
  */
 static bool __es_scan_range(struct inode *inode,
                 int (*matching_fn)(struct extent_status *es),
                 ext4_lblk_t start, ext4_lblk_t end)
 {
     struct extent_status es;
 
     __es_find_extent_range(inode, matching_fn, start, end, &es);
     if (es.es_len == 0)
         return false;   /* no matching extent in the tree */
     else if (es.es_lblk <= start &&
          start < es.es_lblk + es.es_len)
         return true;
     else if (start <= es.es_lblk && es.es_lblk <= end)
         return true;
     else
         return false;
 }
 /*
  * Locking for __es_scan_range() for external use
  */
 bool ext4_es_scan_range(struct inode *inode,
             int (*matching_fn)(struct extent_status *es),
             ext4_lblk_t lblk, ext4_lblk_t end)
 {
     bool ret;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return false;
 
     read_lock(&EXT4_I(inode)->i_es_lock);
     ret = __es_scan_range(inode, matching_fn, lblk, end);
     read_unlock(&EXT4_I(inode)->i_es_lock);
 
     return ret;
 }
 
 /*
  * __es_scan_clu - search cluster for block with specified status in
  *                 extents status tree
  *
  * @inode - file containing the cluster
  * @matching_fn - pointer to function that matches extents with desired status
  * @lblk - logical block in cluster to be searched
  *
  * Returns true if at least one extent in the cluster containing @lblk
  * satisfies the criterion specified by @matching_fn, and false if not.  If at
  * least one extent has the specified status, then there is at least one block
  * in the cluster with that status.  Should only be called by code that has
  * taken i_es_lock.
  */
 static bool __es_scan_clu(struct inode *inode,
               int (*matching_fn)(struct extent_status *es),
               ext4_lblk_t lblk)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     ext4_lblk_t lblk_start, lblk_end;
 
     lblk_start = EXT4_LBLK_CMASK(sbi, lblk);
     lblk_end = lblk_start + sbi->s_cluster_ratio - 1;
 
     return __es_scan_range(inode, matching_fn, lblk_start, lblk_end);
 }
 
 /*
  * Locking for __es_scan_clu() for external use
  */
 bool ext4_es_scan_clu(struct inode *inode,
               int (*matching_fn)(struct extent_status *es),
               ext4_lblk_t lblk)
 {
     bool ret;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return false;
 
     read_lock(&EXT4_I(inode)->i_es_lock);
     ret = __es_scan_clu(inode, matching_fn, lblk);
     read_unlock(&EXT4_I(inode)->i_es_lock);
 
     return ret;
 }
 
 static void ext4_es_list_add(struct inode *inode)
 {
     struct ext4_inode_info *ei = EXT4_I(inode);
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
     if (!list_empty(&ei->i_es_list))
         return;
 
     spin_lock(&sbi->s_es_lock);
     if (list_empty(&ei->i_es_list)) {
         list_add_tail(&ei->i_es_list, &sbi->s_es_list);
         sbi->s_es_nr_inode++;
     }
     spin_unlock(&sbi->s_es_lock);
 }
 
 static void ext4_es_list_del(struct inode *inode)
 {
     struct ext4_inode_info *ei = EXT4_I(inode);
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
     spin_lock(&sbi->s_es_lock);
     if (!list_empty(&ei->i_es_list)) {
         list_del_init(&ei->i_es_list);
         sbi->s_es_nr_inode--;
         WARN_ON_ONCE(sbi->s_es_nr_inode < 0);
     }
     spin_unlock(&sbi->s_es_lock);
 }
 
 static struct extent_status *
 ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len,
              ext4_fsblk_t pblk)
 {
     struct extent_status *es;
     es = kmem_cache_alloc(ext4_es_cachep, GFP_ATOMIC);
     if (es == NULL)
         return NULL;
     es->es_lblk = lblk;
     es->es_len = len;
     es->es_pblk = pblk;
 
     /*
      * We don't count delayed extent because we never try to reclaim them
      */
     if (!ext4_es_is_delayed(es)) {
         if (!EXT4_I(inode)->i_es_shk_nr++)
             ext4_es_list_add(inode);
         percpu_counter_inc(&EXT4_SB(inode->i_sb)->
                     s_es_stats.es_stats_shk_cnt);
     }
 
     EXT4_I(inode)->i_es_all_nr++;
     percpu_counter_inc(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt);
 
     return es;
 }
 
 static void ext4_es_free_extent(struct inode *inode, struct extent_status *es)
 {
     EXT4_I(inode)->i_es_all_nr--;
     percpu_counter_dec(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt);
 
     /* Decrease the shrink counter when this es is not delayed */
     if (!ext4_es_is_delayed(es)) {
         BUG_ON(EXT4_I(inode)->i_es_shk_nr == 0);
         if (!--EXT4_I(inode)->i_es_shk_nr)
             ext4_es_list_del(inode);
         percpu_counter_dec(&EXT4_SB(inode->i_sb)->
                     s_es_stats.es_stats_shk_cnt);
     }
 
     kmem_cache_free(ext4_es_cachep, es);
 }
 
 /*
  * Check whether or not two extents can be merged
  * Condition:
  *  - logical block number is contiguous
  *  - physical block number is contiguous
  *  - status is equal
  */
 static int ext4_es_can_be_merged(struct extent_status *es1,
                  struct extent_status *es2)
 {
     if (ext4_es_type(es1) != ext4_es_type(es2))
         return 0;
 
     if (((__u64) es1->es_len) + es2->es_len > EXT_MAX_BLOCKS) {
         pr_warn("ES assertion failed when merging extents. "
             "The sum of lengths of es1 (%d) and es2 (%d) "
             "is bigger than allowed file size (%d)\n",
             es1->es_len, es2->es_len, EXT_MAX_BLOCKS);
         WARN_ON(1);
         return 0;
     }
 
     if (((__u64) es1->es_lblk) + es1->es_len != es2->es_lblk)
         return 0;
 
     if ((ext4_es_is_written(es1) || ext4_es_is_unwritten(es1)) &&
         (ext4_es_pblock(es1) + es1->es_len == ext4_es_pblock(es2)))
         return 1;
 
     if (ext4_es_is_hole(es1))
         return 1;
 
     /* we need to check delayed extent is without unwritten status */
     if (ext4_es_is_delayed(es1) && !ext4_es_is_unwritten(es1))
         return 1;
 
     return 0;
 }
 
 static struct extent_status *
 ext4_es_try_to_merge_left(struct inode *inode, struct extent_status *es)
 {
     struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree;
     struct extent_status *es1;
     struct rb_node *node;
 
     node = rb_prev(&es->rb_node);
     if (!node)
         return es;
 
     es1 = rb_entry(node, struct extent_status, rb_node);
     if (ext4_es_can_be_merged(es1, es)) {
         es1->es_len += es->es_len;
         if (ext4_es_is_referenced(es))
             ext4_es_set_referenced(es1);
         rb_erase(&es->rb_node, &tree->root);
         ext4_es_free_extent(inode, es);
         es = es1;
     }
 
     return es;
 }
 
 static struct extent_status *
 ext4_es_try_to_merge_right(struct inode *inode, struct extent_status *es)
 {
     struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree;
     struct extent_status *es1;
     struct rb_node *node;
 
     node = rb_next(&es->rb_node);
     if (!node)
         return es;
 
     es1 = rb_entry(node, struct extent_status, rb_node);
     if (ext4_es_can_be_merged(es, es1)) {
         es->es_len += es1->es_len;
         if (ext4_es_is_referenced(es1))
             ext4_es_set_referenced(es);
         rb_erase(node, &tree->root);
         ext4_es_free_extent(inode, es1);
     }
 
     return es;
 }
 
 #ifdef ES_AGGRESSIVE_TEST
 #include "ext4_extents.h"   /* Needed when ES_AGGRESSIVE_TEST is defined */
 
 static void ext4_es_insert_extent_ext_check(struct inode *inode,
                         struct extent_status *es)
 {
     struct ext4_ext_path *path = NULL;
     struct ext4_extent *ex;
     ext4_lblk_t ee_block;
     ext4_fsblk_t ee_start;
     unsigned short ee_len;
     int depth, ee_status, es_status;
 
     path = ext4_find_extent(inode, es->es_lblk, NULL, EXT4_EX_NOCACHE);
     if (IS_ERR(path))
         return;
 
     depth = ext_depth(inode);
     ex = path[depth].p_ext;
 
     if (ex) {
 
         ee_block = le32_to_cpu(ex->ee_block);
         ee_start = ext4_ext_pblock(ex);
         ee_len = ext4_ext_get_actual_len(ex);
 
         ee_status = ext4_ext_is_unwritten(ex) ? 1 : 0;
         es_status = ext4_es_is_unwritten(es) ? 1 : 0;
 
         /*
          * Make sure ex and es are not overlap when we try to insert
          * a delayed/hole extent.
          */
         if (!ext4_es_is_written(es) && !ext4_es_is_unwritten(es)) {
             if (in_range(es->es_lblk, ee_block, ee_len)) {
                 pr_warn("ES insert assertion failed for "
                     "inode: %lu we can find an extent "
                     "at block [%d/%d/%llu/%c], but we "
                     "want to add a delayed/hole extent "
                     "[%d/%d/%llu/%x]\n",
                     inode->i_ino, ee_block, ee_len,
                     ee_start, ee_status ? 'u' : 'w',
                     es->es_lblk, es->es_len,
                     ext4_es_pblock(es), ext4_es_status(es));
             }
             goto out;
         }
 
         /*
          * We don't check ee_block == es->es_lblk, etc. because es
          * might be a part of whole extent, vice versa.
          */
         if (es->es_lblk < ee_block ||
             ext4_es_pblock(es) != ee_start + es->es_lblk - ee_block) {
             pr_warn("ES insert assertion failed for inode: %lu "
                 "ex_status [%d/%d/%llu/%c] != "
                 "es_status [%d/%d/%llu/%c]\n", inode->i_ino,
                 ee_block, ee_len, ee_start,
                 ee_status ? 'u' : 'w', es->es_lblk, es->es_len,
                 ext4_es_pblock(es), es_status ? 'u' : 'w');
             goto out;
         }
 
         if (ee_status ^ es_status) {
             pr_warn("ES insert assertion failed for inode: %lu "
                 "ex_status [%d/%d/%llu/%c] != "
                 "es_status [%d/%d/%llu/%c]\n", inode->i_ino,
                 ee_block, ee_len, ee_start,
                 ee_status ? 'u' : 'w', es->es_lblk, es->es_len,
                 ext4_es_pblock(es), es_status ? 'u' : 'w');
         }
     } else {
         /*
          * We can't find an extent on disk.  So we need to make sure
          * that we don't want to add an written/unwritten extent.
          */
         if (!ext4_es_is_delayed(es) && !ext4_es_is_hole(es)) {
             pr_warn("ES insert assertion failed for inode: %lu "
                 "can't find an extent at block %d but we want "
                 "to add a written/unwritten extent "
                 "[%d/%d/%llu/%x]\n", inode->i_ino,
                 es->es_lblk, es->es_lblk, es->es_len,
                 ext4_es_pblock(es), ext4_es_status(es));
         }
     }
 out:
     ext4_ext_drop_refs(path);
     kfree(path);
 }
 
 static void ext4_es_insert_extent_ind_check(struct inode *inode,
                         struct extent_status *es)
 {
     struct ext4_map_blocks map;
     int retval;
 
     /*
      * Here we call ext4_ind_map_blocks to lookup a block mapping because
      * 'Indirect' structure is defined in indirect.c.  So we couldn't
      * access direct/indirect tree from outside.  It is too dirty to define
      * this function in indirect.c file.
      */
 
     map.m_lblk = es->es_lblk;
     map.m_len = es->es_len;
 
     retval = ext4_ind_map_blocks(NULL, inode, &map, 0);
     if (retval > 0) {
         if (ext4_es_is_delayed(es) || ext4_es_is_hole(es)) {
             /*
              * We want to add a delayed/hole extent but this
              * block has been allocated.
              */
             pr_warn("ES insert assertion failed for inode: %lu "
                 "We can find blocks but we want to add a "
                 "delayed/hole extent [%d/%d/%llu/%x]\n",
                 inode->i_ino, es->es_lblk, es->es_len,
                 ext4_es_pblock(es), ext4_es_status(es));
             return;
         } else if (ext4_es_is_written(es)) {
             if (retval != es->es_len) {
                 pr_warn("ES insert assertion failed for "
                     "inode: %lu retval %d != es_len %d\n",
                     inode->i_ino, retval, es->es_len);
                 return;
             }
             if (map.m_pblk != ext4_es_pblock(es)) {
                 pr_warn("ES insert assertion failed for "
                     "inode: %lu m_pblk %llu != "
                     "es_pblk %llu\n",
                     inode->i_ino, map.m_pblk,
                     ext4_es_pblock(es));
                 return;
             }
         } else {
             /*
              * We don't need to check unwritten extent because
              * indirect-based file doesn't have it.
              */
             BUG();
         }
     } else if (retval == 0) {
         if (ext4_es_is_written(es)) {
             pr_warn("ES insert assertion failed for inode: %lu "
                 "We can't find the block but we want to add "
                 "a written extent [%d/%d/%llu/%x]\n",
                 inode->i_ino, es->es_lblk, es->es_len,
                 ext4_es_pblock(es), ext4_es_status(es));
             return;
         }
     }
 }
 
 static inline void ext4_es_insert_extent_check(struct inode *inode,
                            struct extent_status *es)
 {
     /*
      * We don't need to worry about the race condition because
      * caller takes i_data_sem locking.
      */
     BUG_ON(!rwsem_is_locked(&EXT4_I(inode)->i_data_sem));
     if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
         ext4_es_insert_extent_ext_check(inode, es);
     else
         ext4_es_insert_extent_ind_check(inode, es);
 }
 #else
 static inline void ext4_es_insert_extent_check(struct inode *inode,
                            struct extent_status *es)
 {
 }
 #endif
 
 static int __es_insert_extent(struct inode *inode, struct extent_status *newes)
 {
     struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree;
     struct rb_node **p = &tree->root.rb_node;
     struct rb_node *parent = NULL;
     struct extent_status *es;
 
     while (*p) {
         parent = *p;
         es = rb_entry(parent, struct extent_status, rb_node);
 
         if (newes->es_lblk < es->es_lblk) {
             if (ext4_es_can_be_merged(newes, es)) {
                 /*
                  * Here we can modify es_lblk directly
                  * because it isn't overlapped.
                  */
                 es->es_lblk = newes->es_lblk;
                 es->es_len += newes->es_len;
                 if (ext4_es_is_written(es) ||
                     ext4_es_is_unwritten(es))
                     ext4_es_store_pblock(es,
                                  newes->es_pblk);
                 es = ext4_es_try_to_merge_left(inode, es);
                 goto out;
             }
             p = &(*p)->rb_left;
         } else if (newes->es_lblk > ext4_es_end(es)) {
             if (ext4_es_can_be_merged(es, newes)) {
                 es->es_len += newes->es_len;
                 es = ext4_es_try_to_merge_right(inode, es);
                 goto out;
             }
             p = &(*p)->rb_right;
         } else {
             BUG();
             return -EINVAL;
         }
     }
 
     es = ext4_es_alloc_extent(inode, newes->es_lblk, newes->es_len,
                   newes->es_pblk);
     if (!es)
         return -ENOMEM;
     rb_link_node(&es->rb_node, parent, p);
     rb_insert_color(&es->rb_node, &tree->root);
 
 out:
     tree->cache_es = es;
     return 0;
 }
 
 /*
  * ext4_es_insert_extent() adds information to an inode's extent
  * status tree.
  *
  * Return 0 on success, error code on failure.
  */
 int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
               ext4_lblk_t len, ext4_fsblk_t pblk,
               unsigned int status)
 {
     struct extent_status newes;
     ext4_lblk_t end = lblk + len - 1;
     int err = 0;
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return 0;
 
     es_debug("add [%u/%u) %llu %x to extent status tree of inode %lu\n",
          lblk, len, pblk, status, inode->i_ino);
 
     if (!len)
         return 0;
 
     BUG_ON(end < lblk);
 
     if ((status & EXTENT_STATUS_DELAYED) &&
         (status & EXTENT_STATUS_WRITTEN)) {
         ext4_warning(inode->i_sb, "Inserting extent [%u/%u] as "
                 " delayed and written which can potentially "
                 " cause data loss.", lblk, len);
         WARN_ON(1);
     }
 
     newes.es_lblk = lblk;
     newes.es_len = len;
     ext4_es_store_pblock_status(&newes, pblk, status);
     trace_ext4_es_insert_extent(inode, &newes);
 
     ext4_es_insert_extent_check(inode, &newes);
 
     write_lock(&EXT4_I(inode)->i_es_lock);
     err = __es_remove_extent(inode, lblk, end, NULL);
     if (err != 0)
         goto error;
 retry:
     err = __es_insert_extent(inode, &newes);
     if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb),
                       128, EXT4_I(inode)))
         goto retry;
     if (err == -ENOMEM && !ext4_es_is_delayed(&newes))
         err = 0;
 
     if (sbi->s_cluster_ratio > 1 && test_opt(inode->i_sb, DELALLOC) &&
         (status & EXTENT_STATUS_WRITTEN ||
          status & EXTENT_STATUS_UNWRITTEN))
         __revise_pending(inode, lblk, len);
 
 error:
     write_unlock(&EXT4_I(inode)->i_es_lock);
 
     ext4_es_print_tree(inode);
 
     return err;
 }
 
 /*
  * ext4_es_cache_extent() inserts information into the extent status
  * tree if and only if there isn't information about the range in
  * question already.
  */
 void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
               ext4_lblk_t len, ext4_fsblk_t pblk,
               unsigned int status)
 {
     struct extent_status *es;
     struct extent_status newes;
     ext4_lblk_t end = lblk + len - 1;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return;
 
     newes.es_lblk = lblk;
     newes.es_len = len;
     ext4_es_store_pblock_status(&newes, pblk, status);
     trace_ext4_es_cache_extent(inode, &newes);
 
     if (!len)
         return;
 
     BUG_ON(end < lblk);
 
     write_lock(&EXT4_I(inode)->i_es_lock);
 
     es = __es_tree_search(&EXT4_I(inode)->i_es_tree.root, lblk);
     if (!es || es->es_lblk > end)
         __es_insert_extent(inode, &newes);
     write_unlock(&EXT4_I(inode)->i_es_lock);
 }
 
 /*
  * ext4_es_lookup_extent() looks up an extent in extent status tree.
  *
  * ext4_es_lookup_extent is called by ext4_map_blocks/ext4_da_map_blocks.
  *
  * Return: 1 on found, 0 on not
  */
 int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
               ext4_lblk_t *next_lblk,
               struct extent_status *es)
 {
     struct ext4_es_tree *tree;
     struct ext4_es_stats *stats;
     struct extent_status *es1 = NULL;
     struct rb_node *node;
     int found = 0;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return 0;
 
     trace_ext4_es_lookup_extent_enter(inode, lblk);
     es_debug("lookup extent in block %u\n", lblk);
 
     tree = &EXT4_I(inode)->i_es_tree;
     read_lock(&EXT4_I(inode)->i_es_lock);
 
     /* find extent in cache firstly */
     es->es_lblk = es->es_len = es->es_pblk = 0;
     if (tree->cache_es) {
         es1 = tree->cache_es;
         if (in_range(lblk, es1->es_lblk, es1->es_len)) {
             es_debug("%u cached by [%u/%u)\n",
                  lblk, es1->es_lblk, es1->es_len);
             found = 1;
             goto out;
         }
     }
 
     node = tree->root.rb_node;
     while (node) {
         es1 = rb_entry(node, struct extent_status, rb_node);
         if (lblk < es1->es_lblk)
             node = node->rb_left;
         else if (lblk > ext4_es_end(es1))
             node = node->rb_right;
         else {
             found = 1;
             break;
         }
     }
 
 out:
     stats = &EXT4_SB(inode->i_sb)->s_es_stats;
     if (found) {
         BUG_ON(!es1);
         es->es_lblk = es1->es_lblk;
         es->es_len = es1->es_len;
         es->es_pblk = es1->es_pblk;
         if (!ext4_es_is_referenced(es1))
             ext4_es_set_referenced(es1);
         percpu_counter_inc(&stats->es_stats_cache_hits);
         if (next_lblk) {
             node = rb_next(&es1->rb_node);
             if (node) {
                 es1 = rb_entry(node, struct extent_status,
                            rb_node);
                 *next_lblk = es1->es_lblk;
             } else
                 *next_lblk = 0;
         }
     } else {
         percpu_counter_inc(&stats->es_stats_cache_misses);
     }
 
     read_unlock(&EXT4_I(inode)->i_es_lock);
 
     trace_ext4_es_lookup_extent_exit(inode, es, found);
     return found;
 }
 
 struct rsvd_count {
     int ndelonly;
     bool first_do_lblk_found;
     ext4_lblk_t first_do_lblk;
     ext4_lblk_t last_do_lblk;
     struct extent_status *left_es;
     bool partial;
     ext4_lblk_t lclu;
 };
 
 /*
  * init_rsvd - initialize reserved count data before removing block range
  *         in file from extent status tree
  *
  * @inode - file containing range
  * @lblk - first block in range
  * @es - pointer to first extent in range
  * @rc - pointer to reserved count data
  *
  * Assumes es is not NULL
  */
 static void init_rsvd(struct inode *inode, ext4_lblk_t lblk,
               struct extent_status *es, struct rsvd_count *rc)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct rb_node *node;
 
     rc->ndelonly = 0;
 
     /*
      * for bigalloc, note the first delonly block in the range has not
      * been found, record the extent containing the block to the left of
      * the region to be removed, if any, and note that there's no partial
      * cluster to track
      */
     if (sbi->s_cluster_ratio > 1) {
         rc->first_do_lblk_found = false;
         if (lblk > es->es_lblk) {
             rc->left_es = es;
         } else {
             node = rb_prev(&es->rb_node);
             rc->left_es = node ? rb_entry(node,
                               struct extent_status,
                               rb_node) : NULL;
         }
         rc->partial = false;
     }
 }
 
 /*
  * count_rsvd - count the clusters containing delayed and not unwritten
  *      (delonly) blocks in a range within an extent and add to
  *          the running tally in rsvd_count
  *
  * @inode - file containing extent
  * @lblk - first block in range
  * @len - length of range in blocks
  * @es - pointer to extent containing clusters to be counted
  * @rc - pointer to reserved count data
  *
  * Tracks partial clusters found at the beginning and end of extents so
  * they aren't overcounted when they span adjacent extents
  */
 static void count_rsvd(struct inode *inode, ext4_lblk_t lblk, long len,
                struct extent_status *es, struct rsvd_count *rc)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     ext4_lblk_t i, end, nclu;
 
     if (!ext4_es_is_delonly(es))
         return;
 
     WARN_ON(len <= 0);
 
     if (sbi->s_cluster_ratio == 1) {
         rc->ndelonly += (int) len;
         return;
     }
 
     /* bigalloc */
 
     i = (lblk < es->es_lblk) ? es->es_lblk : lblk;
     end = lblk + (ext4_lblk_t) len - 1;
     end = (end > ext4_es_end(es)) ? ext4_es_end(es) : end;
 
     /* record the first block of the first delonly extent seen */
     if (!rc->first_do_lblk_found) {
         rc->first_do_lblk = i;
         rc->first_do_lblk_found = true;
     }
 
     /* update the last lblk in the region seen so far */
     rc->last_do_lblk = end;
 
     /*
      * if we're tracking a partial cluster and the current extent
      * doesn't start with it, count it and stop tracking
      */
     if (rc->partial && (rc->lclu != EXT4_B2C(sbi, i))) {
         rc->ndelonly++;
         rc->partial = false;
     }
 
     /*
      * if the first cluster doesn't start on a cluster boundary but
      * ends on one, count it
      */
     if (EXT4_LBLK_COFF(sbi, i) != 0) {
         if (end >= EXT4_LBLK_CFILL(sbi, i)) {
             rc->ndelonly++;
             rc->partial = false;
             i = EXT4_LBLK_CFILL(sbi, i) + 1;
         }
     }
 
     /*
      * if the current cluster starts on a cluster boundary, count the
      * number of whole delonly clusters in the extent
      */
     if ((i + sbi->s_cluster_ratio - 1) <= end) {
         nclu = (end - i + 1) >> sbi->s_cluster_bits;
         rc->ndelonly += nclu;
         i += nclu << sbi->s_cluster_bits;
     }
 
     /*
      * start tracking a partial cluster if there's a partial at the end
      * of the current extent and we're not already tracking one
      */
     if (!rc->partial && i <= end) {
         rc->partial = true;
         rc->lclu = EXT4_B2C(sbi, i);
     }
 }
 
 /*
  * __pr_tree_search - search for a pending cluster reservation
  *
  * @root - root of pending reservation tree
  * @lclu - logical cluster to search for
  *
  * Returns the pending reservation for the cluster identified by @lclu
  * if found.  If not, returns a reservation for the next cluster if any,
  * and if not, returns NULL.
  */
 static struct pending_reservation *__pr_tree_search(struct rb_root *root,
                             ext4_lblk_t lclu)
 {
     struct rb_node *node = root->rb_node;
     struct pending_reservation *pr = NULL;
 
     while (node) {
         pr = rb_entry(node, struct pending_reservation, rb_node);
         if (lclu < pr->lclu)
             node = node->rb_left;
         else if (lclu > pr->lclu)
             node = node->rb_right;
         else
             return pr;
     }
     if (pr && lclu < pr->lclu)
         return pr;
     if (pr && lclu > pr->lclu) {
         node = rb_next(&pr->rb_node);
         return node ? rb_entry(node, struct pending_reservation,
                        rb_node) : NULL;
     }
     return NULL;
 }
 
 /*
  * get_rsvd - calculates and returns the number of cluster reservations to be
  *        released when removing a block range from the extent status tree
  *        and releases any pending reservations within the range
  *
  * @inode - file containing block range
  * @end - last block in range
  * @right_es - pointer to extent containing next block beyond end or NULL
  * @rc - pointer to reserved count data
  *
  * The number of reservations to be released is equal to the number of
  * clusters containing delayed and not unwritten (delonly) blocks within
  * the range, minus the number of clusters still containing delonly blocks
  * at the ends of the range, and minus the number of pending reservations
  * within the range.
  */
 static unsigned int get_rsvd(struct inode *inode, ext4_lblk_t end,
                  struct extent_status *right_es,
                  struct rsvd_count *rc)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct pending_reservation *pr;
     struct ext4_pending_tree *tree = &EXT4_I(inode)->i_pending_tree;
     struct rb_node *node;
     ext4_lblk_t first_lclu, last_lclu;
     bool left_delonly, right_delonly, count_pending;
     struct extent_status *es;
 
     if (sbi->s_cluster_ratio > 1) {
         /* count any remaining partial cluster */
         if (rc->partial)
             rc->ndelonly++;
 
         if (rc->ndelonly == 0)
             return 0;
 
         first_lclu = EXT4_B2C(sbi, rc->first_do_lblk);
         last_lclu = EXT4_B2C(sbi, rc->last_do_lblk);
 
         /*
          * decrease the delonly count by the number of clusters at the
          * ends of the range that still contain delonly blocks -
          * these clusters still need to be reserved
          */
         left_delonly = right_delonly = false;
 
         es = rc->left_es;
         while (es && ext4_es_end(es) >=
                EXT4_LBLK_CMASK(sbi, rc->first_do_lblk)) {
             if (ext4_es_is_delonly(es)) {
                 rc->ndelonly--;
                 left_delonly = true;
                 break;
             }
             node = rb_prev(&es->rb_node);
             if (!node)
                 break;
             es = rb_entry(node, struct extent_status, rb_node);
         }
         if (right_es && (!left_delonly || first_lclu != last_lclu)) {
             if (end < ext4_es_end(right_es)) {
                 es = right_es;
             } else {
                 node = rb_next(&right_es->rb_node);
                 es = node ? rb_entry(node, struct extent_status,
                              rb_node) : NULL;
             }
             while (es && es->es_lblk <=
                    EXT4_LBLK_CFILL(sbi, rc->last_do_lblk)) {
                 if (ext4_es_is_delonly(es)) {
                     rc->ndelonly--;
                     right_delonly = true;
                     break;
                 }
                 node = rb_next(&es->rb_node);
                 if (!node)
                     break;
                 es = rb_entry(node, struct extent_status,
                           rb_node);
             }
         }
 
         /*
          * Determine the block range that should be searched for
          * pending reservations, if any.  Clusters on the ends of the
          * original removed range containing delonly blocks are
          * excluded.  They've already been accounted for and it's not
          * possible to determine if an associated pending reservation
          * should be released with the information available in the
          * extents status tree.
          */
         if (first_lclu == last_lclu) {
             if (left_delonly | right_delonly)
                 count_pending = false;
             else
                 count_pending = true;
         } else {
             if (left_delonly)
                 first_lclu++;
             if (right_delonly)
                 last_lclu--;
             if (first_lclu <= last_lclu)
                 count_pending = true;
             else
                 count_pending = false;
         }
 
         /*
          * a pending reservation found between first_lclu and last_lclu
          * represents an allocated cluster that contained at least one
          * delonly block, so the delonly total must be reduced by one
          * for each pending reservation found and released
          */
         if (count_pending) {
             pr = __pr_tree_search(&tree->root, first_lclu);
             while (pr && pr->lclu <= last_lclu) {
                 rc->ndelonly--;
                 node = rb_next(&pr->rb_node);
                 rb_erase(&pr->rb_node, &tree->root);
                 kmem_cache_free(ext4_pending_cachep, pr);
                 if (!node)
                     break;
                 pr = rb_entry(node, struct pending_reservation,
                           rb_node);
             }
         }
     }
     return rc->ndelonly;
 }
 
 
 /*
  * __es_remove_extent - removes block range from extent status tree
  *
  * @inode - file containing range
  * @lblk - first block in range
  * @end - last block in range
  * @reserved - number of cluster reservations released
  *
  * If @reserved is not NULL and delayed allocation is enabled, counts
  * block/cluster reservations freed by removing range and if bigalloc
  * enabled cancels pending reservations as needed. Returns 0 on success,
  * error code on failure.
  */
 static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                   ext4_lblk_t end, int *reserved)
 {
     struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree;
     struct rb_node *node;
     struct extent_status *es;
     struct extent_status orig_es;
     ext4_lblk_t len1, len2;
     ext4_fsblk_t block;
     int err;
     bool count_reserved = true;
     struct rsvd_count rc;
 
     if (reserved == NULL || !test_opt(inode->i_sb, DELALLOC))
         count_reserved = false;
 retry:
     err = 0;
 
     es = __es_tree_search(&tree->root, lblk);
     if (!es)
         goto out;
     if (es->es_lblk > end)
         goto out;
 
     /* Simply invalidate cache_es. */
     tree->cache_es = NULL;
     if (count_reserved)
         init_rsvd(inode, lblk, es, &rc);
 
     orig_es.es_lblk = es->es_lblk;
     orig_es.es_len = es->es_len;
     orig_es.es_pblk = es->es_pblk;
 
     len1 = lblk > es->es_lblk ? lblk - es->es_lblk : 0;
     len2 = ext4_es_end(es) > end ? ext4_es_end(es) - end : 0;
     if (len1 > 0)
         es->es_len = len1;
     if (len2 > 0) {
         if (len1 > 0) {
             struct extent_status newes;
 
             newes.es_lblk = end + 1;
             newes.es_len = len2;
             block = 0x7FDEADBEEFULL;
             if (ext4_es_is_written(&orig_es) ||
                 ext4_es_is_unwritten(&orig_es))
                 block = ext4_es_pblock(&orig_es) +
                     orig_es.es_len - len2;
             ext4_es_store_pblock_status(&newes, block,
                             ext4_es_status(&orig_es));
             err = __es_insert_extent(inode, &newes);
             if (err) {
                 es->es_lblk = orig_es.es_lblk;
                 es->es_len = orig_es.es_len;
                 if ((err == -ENOMEM) &&
                     __es_shrink(EXT4_SB(inode->i_sb),
                             128, EXT4_I(inode)))
                     goto retry;
                 goto out;
             }
         } else {
             es->es_lblk = end + 1;
             es->es_len = len2;
             if (ext4_es_is_written(es) ||
                 ext4_es_is_unwritten(es)) {
                 block = orig_es.es_pblk + orig_es.es_len - len2;
                 ext4_es_store_pblock(es, block);
             }
         }
         if (count_reserved)
             count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
                    &orig_es, &rc);
         goto out;
     }
 
     if (len1 > 0) {
         if (count_reserved)
             count_rsvd(inode, lblk, orig_es.es_len - len1,
                    &orig_es, &rc);
         node = rb_next(&es->rb_node);
         if (node)
             es = rb_entry(node, struct extent_status, rb_node);
         else
             es = NULL;
     }
 
     while (es && ext4_es_end(es) <= end) {
         if (count_reserved)
             count_rsvd(inode, es->es_lblk, es->es_len, es, &rc);
         node = rb_next(&es->rb_node);
         rb_erase(&es->rb_node, &tree->root);
         ext4_es_free_extent(inode, es);
         if (!node) {
             es = NULL;
             break;
         }
         es = rb_entry(node, struct extent_status, rb_node);
     }
 
     if (es && es->es_lblk < end + 1) {
         ext4_lblk_t orig_len = es->es_len;
 
         len1 = ext4_es_end(es) - end;
         if (count_reserved)
             count_rsvd(inode, es->es_lblk, orig_len - len1,
                    es, &rc);
         es->es_lblk = end + 1;
         es->es_len = len1;
         if (ext4_es_is_written(es) || ext4_es_is_unwritten(es)) {
             block = es->es_pblk + orig_len - len1;
             ext4_es_store_pblock(es, block);
         }
     }
 
     if (count_reserved)
         *reserved = get_rsvd(inode, end, es, &rc);
 out:
     return err;
 }
 
 /*
  * ext4_es_remove_extent - removes block range from extent status tree
  *
  * @inode - file containing range
  * @lblk - first block in range
  * @len - number of blocks to remove
  *
  * Reduces block/cluster reservation count and for bigalloc cancels pending
  * reservations as needed. Returns 0 on success, error code on failure.
  */
 int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
               ext4_lblk_t len)
 {
     ext4_lblk_t end;
     int err = 0;
     int reserved = 0;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return 0;
 
     trace_ext4_es_remove_extent(inode, lblk, len);
     es_debug("remove [%u/%u) from extent status tree of inode %lu\n",
          lblk, len, inode->i_ino);
 
     if (!len)
         return err;
 
     end = lblk + len - 1;
     BUG_ON(end < lblk);
 
     /*
      * ext4_clear_inode() depends on us taking i_es_lock unconditionally
      * so that we are sure __es_shrink() is done with the inode before it
      * is reclaimed.
      */
     write_lock(&EXT4_I(inode)->i_es_lock);
     err = __es_remove_extent(inode, lblk, end, &reserved);
     write_unlock(&EXT4_I(inode)->i_es_lock);
     ext4_es_print_tree(inode);
     ext4_da_release_space(inode, reserved);
     return err;
 }
 
 static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
                struct ext4_inode_info *locked_ei)
 {
     struct ext4_inode_info *ei;
     struct ext4_es_stats *es_stats;
     ktime_t start_time;
     u64 scan_time;
     int nr_to_walk;
     int nr_shrunk = 0;
     int retried = 0, nr_skipped = 0;
 
     es_stats = &sbi->s_es_stats;
     start_time = ktime_get();
 
 retry:
     spin_lock(&sbi->s_es_lock);
     nr_to_walk = sbi->s_es_nr_inode;
     while (nr_to_walk-- > 0) {
         if (list_empty(&sbi->s_es_list)) {
             spin_unlock(&sbi->s_es_lock);
             goto out;
         }
         ei = list_first_entry(&sbi->s_es_list, struct ext4_inode_info,
                       i_es_list);
         /* Move the inode to the tail */
         list_move_tail(&ei->i_es_list, &sbi->s_es_list);
 
         /*
          * Normally we try hard to avoid shrinking precached inodes,
          * but we will as a last resort.
          */
         if (!retried && ext4_test_inode_state(&ei->vfs_inode,
                         EXT4_STATE_EXT_PRECACHED)) {
             nr_skipped++;
             continue;
         }
 
         if (ei == locked_ei || !write_trylock(&ei->i_es_lock)) {
             nr_skipped++;
             continue;
         }
         /*
          * Now we hold i_es_lock which protects us from inode reclaim
          * freeing inode under us
          */
         spin_unlock(&sbi->s_es_lock);
 
         nr_shrunk += es_reclaim_extents(ei, &nr_to_scan);
         write_unlock(&ei->i_es_lock);
 
         if (nr_to_scan <= 0)
             goto out;
         spin_lock(&sbi->s_es_lock);
     }
     spin_unlock(&sbi->s_es_lock);
 
     /*
      * If we skipped any inodes, and we weren't able to make any
      * forward progress, try again to scan precached inodes.
      */
     if ((nr_shrunk == 0) && nr_skipped && !retried) {
         retried++;
         goto retry;
     }
 
     if (locked_ei && nr_shrunk == 0)
         nr_shrunk = es_reclaim_extents(locked_ei, &nr_to_scan);
 
 out:
     scan_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
     if (likely(es_stats->es_stats_scan_time))
         es_stats->es_stats_scan_time = (scan_time +
                 es_stats->es_stats_scan_time*3) / 4;
     else
         es_stats->es_stats_scan_time = scan_time;
     if (scan_time > es_stats->es_stats_max_scan_time)
         es_stats->es_stats_max_scan_time = scan_time;
     if (likely(es_stats->es_stats_shrunk))
         es_stats->es_stats_shrunk = (nr_shrunk +
                 es_stats->es_stats_shrunk*3) / 4;
     else
         es_stats->es_stats_shrunk = nr_shrunk;
 
     trace_ext4_es_shrink(sbi->s_sb, nr_shrunk, scan_time,
                  nr_skipped, retried);
     return nr_shrunk;
 }
 
 static unsigned long ext4_es_count(struct shrinker *shrink,
                    struct shrink_control *sc)
 {
     unsigned long nr;
     struct ext4_sb_info *sbi;
 
     sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker);
     nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt);
     trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr);
     return nr;
 }
 
 static unsigned long ext4_es_scan(struct shrinker *shrink,
                   struct shrink_control *sc)
 {
     struct ext4_sb_info *sbi = container_of(shrink,
                     struct ext4_sb_info, s_es_shrinker);
     int nr_to_scan = sc->nr_to_scan;
     int ret, nr_shrunk;
 
     ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt);
     trace_ext4_es_shrink_scan_enter(sbi->s_sb, nr_to_scan, ret);
 
     nr_shrunk = __es_shrink(sbi, nr_to_scan, NULL);
 
     ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt);
     trace_ext4_es_shrink_scan_exit(sbi->s_sb, nr_shrunk, ret);
     return nr_shrunk;
 }
 
 int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v)
 {
     struct ext4_sb_info *sbi = EXT4_SB((struct super_block *) seq->private);
     struct ext4_es_stats *es_stats = &sbi->s_es_stats;
     struct ext4_inode_info *ei, *max = NULL;
     unsigned int inode_cnt = 0;
 
     if (v != SEQ_START_TOKEN)
         return 0;
 
     /* here we just find an inode that has the max nr. of objects */
     spin_lock(&sbi->s_es_lock);
     list_for_each_entry(ei, &sbi->s_es_list, i_es_list) {
         inode_cnt++;
         if (max && max->i_es_all_nr < ei->i_es_all_nr)
             max = ei;
         else if (!max)
             max = ei;
     }
     spin_unlock(&sbi->s_es_lock);
 
     seq_printf(seq, "stats:\n  %lld objects\n  %lld reclaimable objects\n",
            percpu_counter_sum_positive(&es_stats->es_stats_all_cnt),
            percpu_counter_sum_positive(&es_stats->es_stats_shk_cnt));
     seq_printf(seq, "  %lld/%lld cache hits/misses\n",
            percpu_counter_sum_positive(&es_stats->es_stats_cache_hits),
            percpu_counter_sum_positive(&es_stats->es_stats_cache_misses));
     if (inode_cnt)
         seq_printf(seq, "  %d inodes on list\n", inode_cnt);
 
     seq_printf(seq, "average:\n  %llu us scan time\n",
         div_u64(es_stats->es_stats_scan_time, 1000));
     seq_printf(seq, "  %lu shrunk objects\n", es_stats->es_stats_shrunk);
     if (inode_cnt)
         seq_printf(seq,
             "maximum:\n  %lu inode (%u objects, %u reclaimable)\n"
             "  %llu us max scan time\n",
             max->vfs_inode.i_ino, max->i_es_all_nr, max->i_es_shk_nr,
             div_u64(es_stats->es_stats_max_scan_time, 1000));
 
     return 0;
 }
 
 int ext4_es_register_shrinker(struct ext4_sb_info *sbi)
 {
     int err;
 
     /* Make sure we have enough bits for physical block number */
     BUILD_BUG_ON(ES_SHIFT < 48);
     INIT_LIST_HEAD(&sbi->s_es_list);
     sbi->s_es_nr_inode = 0;
     spin_lock_init(&sbi->s_es_lock);
     sbi->s_es_stats.es_stats_shrunk = 0;
     err = percpu_counter_init(&sbi->s_es_stats.es_stats_cache_hits, 0,
                   GFP_KERNEL);
     if (err)
         return err;
     err = percpu_counter_init(&sbi->s_es_stats.es_stats_cache_misses, 0,
                   GFP_KERNEL);
     if (err)
         goto err1;
     sbi->s_es_stats.es_stats_scan_time = 0;
     sbi->s_es_stats.es_stats_max_scan_time = 0;
     err = percpu_counter_init(&sbi->s_es_stats.es_stats_all_cnt, 0, GFP_KERNEL);
     if (err)
         goto err2;
     err = percpu_counter_init(&sbi->s_es_stats.es_stats_shk_cnt, 0, GFP_KERNEL);
     if (err)
         goto err3;
 
     sbi->s_es_shrinker.scan_objects = ext4_es_scan;
     sbi->s_es_shrinker.count_objects = ext4_es_count;
     sbi->s_es_shrinker.seeks = DEFAULT_SEEKS;
     err = register_shrinker(&sbi->s_es_shrinker, "ext4-es:%s",
                 sbi->s_sb->s_id);
     if (err)
         goto err4;
 
     return 0;
 err4:
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt);
 err3:
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt);
 err2:
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses);
 err1:
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_hits);
     return err;
 }
 
 void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi)
 {
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_hits);
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses);
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt);
     percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt);
     unregister_shrinker(&sbi->s_es_shrinker);
 }
 
 /*
  * Shrink extents in given inode from ei->i_es_shrink_lblk till end. Scan at
  * most *nr_to_scan extents, update *nr_to_scan accordingly.
  *
  * Return 0 if we hit end of tree / interval, 1 if we exhausted nr_to_scan.
  * Increment *nr_shrunk by the number of reclaimed extents. Also update
  * ei->i_es_shrink_lblk to where we should continue scanning.
  */
 static int es_do_reclaim_extents(struct ext4_inode_info *ei, ext4_lblk_t end,
                  int *nr_to_scan, int *nr_shrunk)
 {
     struct inode *inode = &ei->vfs_inode;
     struct ext4_es_tree *tree = &ei->i_es_tree;
     struct extent_status *es;
     struct rb_node *node;
 
     es = __es_tree_search(&tree->root, ei->i_es_shrink_lblk);
     if (!es)
         goto out_wrap;
 
     while (*nr_to_scan > 0) {
         if (es->es_lblk > end) {
             ei->i_es_shrink_lblk = end + 1;
             return 0;
         }
 
         (*nr_to_scan)--;
         node = rb_next(&es->rb_node);
         /*
          * We can't reclaim delayed extent from status tree because
          * fiemap, bigallic, and seek_data/hole need to use it.
          */
         if (ext4_es_is_delayed(es))
             goto next;
         if (ext4_es_is_referenced(es)) {
             ext4_es_clear_referenced(es);
             goto next;
         }
 
         rb_erase(&es->rb_node, &tree->root);
         ext4_es_free_extent(inode, es);
         (*nr_shrunk)++;
 next:
         if (!node)
             goto out_wrap;
         es = rb_entry(node, struct extent_status, rb_node);
     }
     ei->i_es_shrink_lblk = es->es_lblk;
     return 1;
 out_wrap:
     ei->i_es_shrink_lblk = 0;
     return 0;
 }
 
 static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan)
 {
     struct inode *inode = &ei->vfs_inode;
     int nr_shrunk = 0;
     ext4_lblk_t start = ei->i_es_shrink_lblk;
     static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
                       DEFAULT_RATELIMIT_BURST);
 
     if (ei->i_es_shk_nr == 0)
         return 0;
 
     if (ext4_test_inode_state(inode, EXT4_STATE_EXT_PRECACHED) &&
         __ratelimit(&_rs))
         ext4_warning(inode->i_sb, "forced shrink of precached extents");
 
     if (!es_do_reclaim_extents(ei, EXT_MAX_BLOCKS, nr_to_scan, &nr_shrunk) &&
         start != 0)
         es_do_reclaim_extents(ei, start - 1, nr_to_scan, &nr_shrunk);
 
     ei->i_es_tree.cache_es = NULL;
     return nr_shrunk;
 }
 
 /*
  * Called to support EXT4_IOC_CLEAR_ES_CACHE.  We can only remove
  * discretionary entries from the extent status cache.  (Some entries
  * must be present for proper operations.)
  */
 void ext4_clear_inode_es(struct inode *inode)
 {
     struct ext4_inode_info *ei = EXT4_I(inode);
     struct extent_status *es;
     struct ext4_es_tree *tree;
     struct rb_node *node;
 
     write_lock(&ei->i_es_lock);
     tree = &EXT4_I(inode)->i_es_tree;
     tree->cache_es = NULL;
     node = rb_first(&tree->root);
     while (node) {
         es = rb_entry(node, struct extent_status, rb_node);
         node = rb_next(node);
         if (!ext4_es_is_delayed(es)) {
             rb_erase(&es->rb_node, &tree->root);
             ext4_es_free_extent(inode, es);
         }
     }
     ext4_clear_inode_state(inode, EXT4_STATE_EXT_PRECACHED);
     write_unlock(&ei->i_es_lock);
 }
 
 #ifdef ES_DEBUG__
 static void ext4_print_pending_tree(struct inode *inode)
 {
     struct ext4_pending_tree *tree;
     struct rb_node *node;
     struct pending_reservation *pr;
 
     printk(KERN_DEBUG "pending reservations for inode %lu:", inode->i_ino);
     tree = &EXT4_I(inode)->i_pending_tree;
     node = rb_first(&tree->root);
     while (node) {
         pr = rb_entry(node, struct pending_reservation, rb_node);
         printk(KERN_DEBUG " %u", pr->lclu);
         node = rb_next(node);
     }
     printk(KERN_DEBUG "\n");
 }
 #else
 #define ext4_print_pending_tree(inode)
 #endif
 
 int __init ext4_init_pending(void)
 {
     ext4_pending_cachep = kmem_cache_create("ext4_pending_reservation",
                        sizeof(struct pending_reservation),
                        0, (SLAB_RECLAIM_ACCOUNT), NULL);
     if (ext4_pending_cachep == NULL)
         return -ENOMEM;
     return 0;
 }
 
 void ext4_exit_pending(void)
 {
     kmem_cache_destroy(ext4_pending_cachep);
 }
 
 void ext4_init_pending_tree(struct ext4_pending_tree *tree)
 {
     tree->root = RB_ROOT;
 }
 
 /*
  * __get_pending - retrieve a pointer to a pending reservation
  *
  * @inode - file containing the pending cluster reservation
  * @lclu - logical cluster of interest
  *
  * Returns a pointer to a pending reservation if it's a member of
  * the set, and NULL if not.  Must be called holding i_es_lock.
  */
 static struct pending_reservation *__get_pending(struct inode *inode,
                          ext4_lblk_t lclu)
 {
     struct ext4_pending_tree *tree;
     struct rb_node *node;
     struct pending_reservation *pr = NULL;
 
     tree = &EXT4_I(inode)->i_pending_tree;
     node = (&tree->root)->rb_node;
 
     while (node) {
         pr = rb_entry(node, struct pending_reservation, rb_node);
         if (lclu < pr->lclu)
             node = node->rb_left;
         else if (lclu > pr->lclu)
             node = node->rb_right;
         else if (lclu == pr->lclu)
             return pr;
     }
     return NULL;
 }
 
 /*
  * __insert_pending - adds a pending cluster reservation to the set of
  *                    pending reservations
  *
  * @inode - file containing the cluster
  * @lblk - logical block in the cluster to be added
  *
  * Returns 0 on successful insertion and -ENOMEM on failure.  If the
  * pending reservation is already in the set, returns successfully.
  */
 static int __insert_pending(struct inode *inode, ext4_lblk_t lblk)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct ext4_pending_tree *tree = &EXT4_I(inode)->i_pending_tree;
     struct rb_node **p = &tree->root.rb_node;
     struct rb_node *parent = NULL;
     struct pending_reservation *pr;
     ext4_lblk_t lclu;
     int ret = 0;
 
     lclu = EXT4_B2C(sbi, lblk);
     /* search to find parent for insertion */
     while (*p) {
         parent = *p;
         pr = rb_entry(parent, struct pending_reservation, rb_node);
 
         if (lclu < pr->lclu) {
             p = &(*p)->rb_left;
         } else if (lclu > pr->lclu) {
             p = &(*p)->rb_right;
         } else {
             /* pending reservation already inserted */
             goto out;
         }
     }
 
     pr = kmem_cache_alloc(ext4_pending_cachep, GFP_ATOMIC);
     if (pr == NULL) {
         ret = -ENOMEM;
         goto out;
     }
     pr->lclu = lclu;
 
     rb_link_node(&pr->rb_node, parent, p);
     rb_insert_color(&pr->rb_node, &tree->root);
 
 out:
     return ret;
 }
 
 /*
  * __remove_pending - removes a pending cluster reservation from the set
  *                    of pending reservations
  *
  * @inode - file containing the cluster
  * @lblk - logical block in the pending cluster reservation to be removed
  *
  * Returns successfully if pending reservation is not a member of the set.
  */
 static void __remove_pending(struct inode *inode, ext4_lblk_t lblk)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct pending_reservation *pr;
     struct ext4_pending_tree *tree;
 
     pr = __get_pending(inode, EXT4_B2C(sbi, lblk));
     if (pr != NULL) {
         tree = &EXT4_I(inode)->i_pending_tree;
         rb_erase(&pr->rb_node, &tree->root);
         kmem_cache_free(ext4_pending_cachep, pr);
     }
 }
 
 /*
  * ext4_remove_pending - removes a pending cluster reservation from the set
  *                       of pending reservations
  *
  * @inode - file containing the cluster
  * @lblk - logical block in the pending cluster reservation to be removed
  *
  * Locking for external use of __remove_pending.
  */
 void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk)
 {
     struct ext4_inode_info *ei = EXT4_I(inode);
 
     write_lock(&ei->i_es_lock);
     __remove_pending(inode, lblk);
     write_unlock(&ei->i_es_lock);
 }
 
 /*
  * ext4_is_pending - determine whether a cluster has a pending reservation
  *                   on it
  *
  * @inode - file containing the cluster
  * @lblk - logical block in the cluster
  *
  * Returns true if there's a pending reservation for the cluster in the
  * set of pending reservations, and false if not.
  */
 bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct ext4_inode_info *ei = EXT4_I(inode);
     bool ret;
 
     read_lock(&ei->i_es_lock);
     ret = (bool)(__get_pending(inode, EXT4_B2C(sbi, lblk)) != NULL);
     read_unlock(&ei->i_es_lock);
 
     return ret;
 }
 
 /*
  * ext4_es_insert_delayed_block - adds a delayed block to the extents status
  *                                tree, adding a pending reservation where
  *                                needed
  *
  * @inode - file containing the newly added block
  * @lblk - logical block to be added
  * @allocated - indicates whether a physical cluster has been allocated for
  *              the logical cluster that contains the block
  *
  * Returns 0 on success, negative error code on failure.
  */
 int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk,
                  bool allocated)
 {
     struct extent_status newes;
     int err = 0;
 
     if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
         return 0;
 
     es_debug("add [%u/1) delayed to extent status tree of inode %lu\n",
          lblk, inode->i_ino);
 
     newes.es_lblk = lblk;
     newes.es_len = 1;
     ext4_es_store_pblock_status(&newes, ~0, EXTENT_STATUS_DELAYED);
     trace_ext4_es_insert_delayed_block(inode, &newes, allocated);
 
     ext4_es_insert_extent_check(inode, &newes);
 
     write_lock(&EXT4_I(inode)->i_es_lock);
 
     err = __es_remove_extent(inode, lblk, lblk, NULL);
     if (err != 0)
         goto error;
 retry:
     err = __es_insert_extent(inode, &newes);
     if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb),
                       128, EXT4_I(inode)))
         goto retry;
     if (err != 0)
         goto error;
 
     if (allocated)
         __insert_pending(inode, lblk);
 
 error:
     write_unlock(&EXT4_I(inode)->i_es_lock);
 
     ext4_es_print_tree(inode);
     ext4_print_pending_tree(inode);
 
     return err;
 }
 
 /*
  * __es_delayed_clu - count number of clusters containing blocks that
  *                    are delayed only
  *
  * @inode - file containing block range
  * @start - logical block defining start of range
  * @end - logical block defining end of range
  *
  * Returns the number of clusters containing only delayed (not delayed
  * and unwritten) blocks in the range specified by @start and @end.  Any
  * cluster or part of a cluster within the range and containing a delayed
  * and not unwritten block within the range is counted as a whole cluster.
  */
 static unsigned int __es_delayed_clu(struct inode *inode, ext4_lblk_t start,
                      ext4_lblk_t end)
 {
     struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree;
     struct extent_status *es;
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     struct rb_node *node;
     ext4_lblk_t first_lclu, last_lclu;
     unsigned long long last_counted_lclu;
     unsigned int n = 0;
 
     /* guaranteed to be unequal to any ext4_lblk_t value */
     last_counted_lclu = ~0ULL;
 
     es = __es_tree_search(&tree->root, start);
 
     while (es && (es->es_lblk <= end)) {
         if (ext4_es_is_delonly(es)) {
             if (es->es_lblk <= start)
                 first_lclu = EXT4_B2C(sbi, start);
             else
                 first_lclu = EXT4_B2C(sbi, es->es_lblk);
 
             if (ext4_es_end(es) >= end)
                 last_lclu = EXT4_B2C(sbi, end);
             else
                 last_lclu = EXT4_B2C(sbi, ext4_es_end(es));
 
             if (first_lclu == last_counted_lclu)
                 n += last_lclu - first_lclu;
             else
                 n += last_lclu - first_lclu + 1;
             last_counted_lclu = last_lclu;
         }
         node = rb_next(&es->rb_node);
         if (!node)
             break;
         es = rb_entry(node, struct extent_status, rb_node);
     }
 
     return n;
 }
 
 /*
  * ext4_es_delayed_clu - count number of clusters containing blocks that
  *                       are both delayed and unwritten
  *
  * @inode - file containing block range
  * @lblk - logical block defining start of range
  * @len - number of blocks in range
  *
  * Locking for external use of __es_delayed_clu().
  */
 unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk,
                  ext4_lblk_t len)
 {
     struct ext4_inode_info *ei = EXT4_I(inode);
     ext4_lblk_t end;
     unsigned int n;
 
     if (len == 0)
         return 0;
 
     end = lblk + len - 1;
     WARN_ON(end < lblk);
 
     read_lock(&ei->i_es_lock);
 
     n = __es_delayed_clu(inode, lblk, end);
 
     read_unlock(&ei->i_es_lock);
 
     return n;
 }
 
 /*
  * __revise_pending - makes, cancels, or leaves unchanged pending cluster
  *                    reservations for a specified block range depending
  *                    upon the presence or absence of delayed blocks
  *                    outside the range within clusters at the ends of the
  *                    range
  *
  * @inode - file containing the range
  * @lblk - logical block defining the start of range
  * @len  - length of range in blocks
  *
  * Used after a newly allocated extent is added to the extents status tree.
  * Requires that the extents in the range have either written or unwritten
  * status.  Must be called while holding i_es_lock.
  */
 static void __revise_pending(struct inode *inode, ext4_lblk_t lblk,
                  ext4_lblk_t len)
 {
     struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     ext4_lblk_t end = lblk + len - 1;
     ext4_lblk_t first, last;
     bool f_del = false, l_del = false;
 
     if (len == 0)
         return;
 
     /*
      * Two cases - block range within single cluster and block range
      * spanning two or more clusters.  Note that a cluster belonging
      * to a range starting and/or ending on a cluster boundary is treated
      * as if it does not contain a delayed extent.  The new range may
      * have allocated space for previously delayed blocks out to the
      * cluster boundary, requiring that any pre-existing pending
      * reservation be canceled.  Because this code only looks at blocks
      * outside the range, it should revise pending reservations
      * correctly even if the extent represented by the range can't be
      * inserted in the extents status tree due to ENOSPC.
      */
 
     if (EXT4_B2C(sbi, lblk) == EXT4_B2C(sbi, end)) {
         first = EXT4_LBLK_CMASK(sbi, lblk);
         if (first != lblk)
             f_del = __es_scan_range(inode, &ext4_es_is_delonly,
                         first, lblk - 1);
         if (f_del) {
             __insert_pending(inode, first);
         } else {
             last = EXT4_LBLK_CMASK(sbi, end) +
                    sbi->s_cluster_ratio - 1;
             if (last != end)
                 l_del = __es_scan_range(inode,
                             &ext4_es_is_delonly,
                             end + 1, last);
             if (l_del)
                 __insert_pending(inode, last);
             else
                 __remove_pending(inode, last);
         }
     } else {
         first = EXT4_LBLK_CMASK(sbi, lblk);
         if (first != lblk)
             f_del = __es_scan_range(inode, &ext4_es_is_delonly,
                         first, lblk - 1);
         if (f_del)
             __insert_pending(inode, first);
         else
             __remove_pending(inode, first);
 
         last = EXT4_LBLK_CMASK(sbi, end) + sbi->s_cluster_ratio - 1;
         if (last != end)
             l_del = __es_scan_range(inode, &ext4_es_is_delonly,
                         end + 1, last);
         if (l_del)
             __insert_pending(inode, last);
         else
             __remove_pending(inode, last);
     }
 }

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