int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info);
 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info);
 int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync);
-void btrfs_drop_extent_cache(struct btrfs_inode *inode, u64 start, u64 end,
-                            int skip_pinned);
 extern const struct file_operations btrfs_file_operations;
 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
                       struct btrfs_root *root, struct btrfs_inode *inode,
 
 #include "volumes.h"
 #include "extent_map.h"
 #include "compression.h"
+#include "btrfs_inode.h"
 
 
 static struct kmem_cache *extent_map_cache;
        ASSERT(ret == 0 || ret == -EEXIST);
        return ret;
 }
+
+/*
+ * Drop all extent maps in a given range.
+ *
+ * @inode:       The target inode.
+ * @start:       Start offset of the range.
+ * @end:         End offset of the range (inclusive value).
+ * @skip_pinned: Indicate if pinned extent maps should be ignored or not.
+ *
+ * This drops all the extent maps that intersect the given range [@start, @end].
+ * Extent maps that partially overlap the range and extend behind or beyond it,
+ * are split.
+ * The caller should have locked an appropriate file range in the inode's io
+ * tree before calling this function.
+ */
+void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
+                                bool skip_pinned)
+{
+       struct extent_map *split = NULL;
+       struct extent_map *split2 = NULL;
+       struct extent_map_tree *em_tree = &inode->extent_tree;
+       u64 len = end - start + 1;
+       bool testend = true;
+
+       WARN_ON(end < start);
+       if (end == (u64)-1) {
+               len = (u64)-1;
+               testend = false;
+       }
+       while (1) {
+               struct extent_map *em;
+               u64 gen;
+               unsigned long flags;
+               bool ends_after_range = false;
+               bool no_splits = false;
+               bool modified;
+               bool compressed;
+
+               if (!split)
+                       split = alloc_extent_map();
+               if (!split2)
+                       split2 = alloc_extent_map();
+               if (!split || !split2)
+                       no_splits = true;
+
+               write_lock(&em_tree->lock);
+               em = lookup_extent_mapping(em_tree, start, len);
+               if (!em) {
+                       write_unlock(&em_tree->lock);
+                       break;
+               }
+               if (testend && em->start + em->len > start + len)
+                       ends_after_range = true;
+               if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
+                       if (ends_after_range) {
+                               free_extent_map(em);
+                               write_unlock(&em_tree->lock);
+                               break;
+                       }
+                       start = em->start + em->len;
+                       if (testend)
+                               len = start + len - (em->start + em->len);
+                       free_extent_map(em);
+                       write_unlock(&em_tree->lock);
+                       continue;
+               }
+               flags = em->flags;
+               gen = em->generation;
+               compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+               clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+               clear_bit(EXTENT_FLAG_LOGGING, &flags);
+               modified = !list_empty(&em->list);
+               if (no_splits)
+                       goto next;
+
+               if (em->start < start) {
+                       split->start = em->start;
+                       split->len = start - em->start;
+
+                       if (em->block_start < EXTENT_MAP_LAST_BYTE) {
+                               split->orig_start = em->orig_start;
+                               split->block_start = em->block_start;
+
+                               if (compressed)
+                                       split->block_len = em->block_len;
+                               else
+                                       split->block_len = split->len;
+                               split->orig_block_len = max(split->block_len,
+                                               em->orig_block_len);
+                               split->ram_bytes = em->ram_bytes;
+                       } else {
+                               split->orig_start = split->start;
+                               split->block_len = 0;
+                               split->block_start = em->block_start;
+                               split->orig_block_len = 0;
+                               split->ram_bytes = split->len;
+                       }
+
+                       split->generation = gen;
+                       split->flags = flags;
+                       split->compress_type = em->compress_type;
+                       replace_extent_mapping(em_tree, em, split, modified);
+                       free_extent_map(split);
+                       split = split2;
+                       split2 = NULL;
+               }
+               if (ends_after_range) {
+                       split->start = start + len;
+                       split->len = em->start + em->len - (start + len);
+                       split->block_start = em->block_start;
+                       split->flags = flags;
+                       split->compress_type = em->compress_type;
+                       split->generation = gen;
+
+                       if (em->block_start < EXTENT_MAP_LAST_BYTE) {
+                               split->orig_block_len = max(em->block_len,
+                                                   em->orig_block_len);
+
+                               split->ram_bytes = em->ram_bytes;
+                               if (compressed) {
+                                       split->block_len = em->block_len;
+                                       split->orig_start = em->orig_start;
+                               } else {
+                                       const u64 diff = start + len - em->start;
+
+                                       split->block_len = split->len;
+                                       split->block_start += diff;
+                                       split->orig_start = em->orig_start;
+                               }
+                       } else {
+                               split->ram_bytes = split->len;
+                               split->orig_start = split->start;
+                               split->block_len = 0;
+                               split->orig_block_len = 0;
+                       }
+
+                       if (extent_map_in_tree(em)) {
+                               replace_extent_mapping(em_tree, em, split,
+                                                      modified);
+                       } else {
+                               int ret;
+
+                               ret = add_extent_mapping(em_tree, split,
+                                                        modified);
+                               /* Logic error, shouldn't happen. */
+                               ASSERT(ret == 0);
+                               if (WARN_ON(ret != 0) && modified)
+                                       btrfs_set_inode_full_sync(inode);
+                       }
+                       free_extent_map(split);
+                       split = NULL;
+               }
+next:
+               if (extent_map_in_tree(em)) {
+                       /*
+                        * If the extent map is still in the tree it means that
+                        * either of the following is true:
+                        *
+                        * 1) It fits entirely in our range (doesn't end beyond
+                        *    it or starts before it);
+                        *
+                        * 2) It starts before our range and/or ends after our
+                        *    range, and we were not able to allocate the extent
+                        *    maps for split operations, @split and @split2.
+                        *
+                        * If we are at case 2) then we just remove the entire
+                        * extent map - this is fine since if anyone needs it to
+                        * access the subranges outside our range, will just
+                        * load it again from the subvolume tree's file extent
+                        * item. However if the extent map was in the list of
+                        * modified extents, then we must mark the inode for a
+                        * full fsync, otherwise a fast fsync will miss this
+                        * extent if it's new and needs to be logged.
+                        */
+                       if ((em->start < start || ends_after_range) && modified) {
+                               ASSERT(no_splits);
+                               btrfs_set_inode_full_sync(inode);
+                       }
+                       remove_extent_mapping(em_tree, em);
+               }
+               write_unlock(&em_tree->lock);
+
+               /* Once for us. */
+               free_extent_map(em);
+               /* And once for the tree. */
+               free_extent_map(em);
+       }
+
+       free_extent_map(split);
+       free_extent_map(split2);
+}
 
        rwlock_t lock;
 };
 
+struct btrfs_inode;
+
 static inline int extent_map_in_tree(const struct extent_map *em)
 {
        return !RB_EMPTY_NODE(&em->rb_node);
 int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
                             struct extent_map_tree *em_tree,
                             struct extent_map **em_in, u64 start, u64 len);
+void btrfs_drop_extent_map_range(struct btrfs_inode *inode,
+                                u64 start, u64 end,
+                                bool skip_pinned);
 
 #endif
 
        return 0;
 }
 
-/*
- * this drops all the extents in the cache that intersect the range
- * [start, end].  Existing extents are split as required.
- */
-void btrfs_drop_extent_cache(struct btrfs_inode *inode, u64 start, u64 end,
-                            int skip_pinned)
-{
-       struct extent_map *em;
-       struct extent_map *split = NULL;
-       struct extent_map *split2 = NULL;
-       struct extent_map_tree *em_tree = &inode->extent_tree;
-       u64 len = end - start + 1;
-       u64 gen;
-       int ret;
-       int testend = 1;
-       unsigned long flags;
-       int compressed = 0;
-       bool modified;
-
-       WARN_ON(end < start);
-       if (end == (u64)-1) {
-               len = (u64)-1;
-               testend = 0;
-       }
-       while (1) {
-               bool ends_after_range = false;
-               int no_splits = 0;
-
-               modified = false;
-               if (!split)
-                       split = alloc_extent_map();
-               if (!split2)
-                       split2 = alloc_extent_map();
-               if (!split || !split2)
-                       no_splits = 1;
-
-               write_lock(&em_tree->lock);
-               em = lookup_extent_mapping(em_tree, start, len);
-               if (!em) {
-                       write_unlock(&em_tree->lock);
-                       break;
-               }
-               if (testend && em->start + em->len > start + len)
-                       ends_after_range = true;
-               flags = em->flags;
-               gen = em->generation;
-               if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
-                       if (ends_after_range) {
-                               free_extent_map(em);
-                               write_unlock(&em_tree->lock);
-                               break;
-                       }
-                       start = em->start + em->len;
-                       if (testend)
-                               len = start + len - (em->start + em->len);
-                       free_extent_map(em);
-                       write_unlock(&em_tree->lock);
-                       continue;
-               }
-               compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
-               clear_bit(EXTENT_FLAG_PINNED, &em->flags);
-               clear_bit(EXTENT_FLAG_LOGGING, &flags);
-               modified = !list_empty(&em->list);
-               if (no_splits)
-                       goto next;
-
-               if (em->start < start) {
-                       split->start = em->start;
-                       split->len = start - em->start;
-
-                       if (em->block_start < EXTENT_MAP_LAST_BYTE) {
-                               split->orig_start = em->orig_start;
-                               split->block_start = em->block_start;
-
-                               if (compressed)
-                                       split->block_len = em->block_len;
-                               else
-                                       split->block_len = split->len;
-                               split->orig_block_len = max(split->block_len,
-                                               em->orig_block_len);
-                               split->ram_bytes = em->ram_bytes;
-                       } else {
-                               split->orig_start = split->start;
-                               split->block_len = 0;
-                               split->block_start = em->block_start;
-                               split->orig_block_len = 0;
-                               split->ram_bytes = split->len;
-                       }
-
-                       split->generation = gen;
-                       split->flags = flags;
-                       split->compress_type = em->compress_type;
-                       replace_extent_mapping(em_tree, em, split, modified);
-                       free_extent_map(split);
-                       split = split2;
-                       split2 = NULL;
-               }
-               if (ends_after_range) {
-                       u64 diff = start + len - em->start;
-
-                       split->start = start + len;
-                       split->len = em->start + em->len - (start + len);
-                       split->flags = flags;
-                       split->compress_type = em->compress_type;
-                       split->generation = gen;
-
-                       if (em->block_start < EXTENT_MAP_LAST_BYTE) {
-                               split->orig_block_len = max(em->block_len,
-                                                   em->orig_block_len);
-
-                               split->ram_bytes = em->ram_bytes;
-                               if (compressed) {
-                                       split->block_len = em->block_len;
-                                       split->block_start = em->block_start;
-                                       split->orig_start = em->orig_start;
-                               } else {
-                                       split->block_len = split->len;
-                                       split->block_start = em->block_start
-                                               + diff;
-                                       split->orig_start = em->orig_start;
-                               }
-                       } else {
-                               split->ram_bytes = split->len;
-                               split->orig_start = split->start;
-                               split->block_len = 0;
-                               split->block_start = em->block_start;
-                               split->orig_block_len = 0;
-                       }
-
-                       if (extent_map_in_tree(em)) {
-                               replace_extent_mapping(em_tree, em, split,
-                                                      modified);
-                       } else {
-                               ret = add_extent_mapping(em_tree, split,
-                                                        modified);
-                               /* Logic error, shouldn't happen. */
-                               ASSERT(ret == 0);
-                               if (WARN_ON(ret != 0) && modified)
-                                       btrfs_set_inode_full_sync(inode);
-                       }
-                       free_extent_map(split);
-                       split = NULL;
-               }
-next:
-               if (extent_map_in_tree(em)) {
-                       /*
-                        * If the extent map is still in the tree it means that
-                        * either of the following is true:
-                        *
-                        * 1) It fits entirely in our range (doesn't end beyond
-                        *    it or starts before it);
-                        *
-                        * 2) It starts before our range and/or ends after our
-                        *    range, and we were not able to allocate the extent
-                        *    maps for split operations, @split and @split2.
-                        *
-                        * If we are at case 2) then we just remove the entire
-                        * extent map - this is fine since if anyone needs it to
-                        * access the subranges outside our range, will just
-                        * load it again from the subvolume tree's file extent
-                        * item. However if the extent map was in the list of
-                        * modified extents, then we must mark the inode for a
-                        * full fsync, otherwise a fast fsync will miss this
-                        * extent if it's new and needs to be logged.
-                        */
-                       if ((em->start < start || ends_after_range) && modified) {
-                               ASSERT(no_splits);
-                               btrfs_set_inode_full_sync(inode);
-                       }
-                       remove_extent_mapping(em_tree, em);
-               }
-               write_unlock(&em_tree->lock);
-
-               /* once for us */
-               free_extent_map(em);
-               /* once for the tree*/
-               free_extent_map(em);
-       }
-       if (split)
-               free_extent_map(split);
-       if (split2)
-               free_extent_map(split2);
-}
-
 /*
  * this is very complex, but the basic idea is to drop all extents
  * in the range start - end.  hint_block is filled in with a block number
        }
 
        if (args->drop_cache)
-               btrfs_drop_extent_cache(inode, args->start, args->end - 1, 0);
+               btrfs_drop_extent_map_range(inode, args->start, args->end - 1, false);
 
        if (args->start >= inode->disk_i_size && !args->replace_extent)
                modify_tree = 0;
 
        hole_em = alloc_extent_map();
        if (!hole_em) {
-               btrfs_drop_extent_cache(inode, offset, end - 1, 0);
+               btrfs_drop_extent_map_range(inode, offset, end - 1, false);
                btrfs_set_inode_full_sync(inode);
        } else {
                hole_em->start = offset;
                hole_em->generation = trans->transid;
 
                do {
-                       btrfs_drop_extent_cache(inode, offset, end - 1, 0);
+                       btrfs_drop_extent_map_range(inode, offset, end - 1, false);
                        write_lock(&em_tree->lock);
                        ret = add_extent_mapping(em_tree, hole_em, 1);
                        write_unlock(&em_tree->lock);
 
        truncate_pagecache(vfs_inode, 0);
 
        lock_extent(&inode->io_tree, 0, (u64)-1, &cached_state);
-       btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
+       btrfs_drop_extent_map_range(inode, 0, (u64)-1, false);
 
        /*
         * We skip the throttling logic for free space cache inodes, so we don't
 
                                       1 << BTRFS_ORDERED_COMPRESSED,
                                       async_extent->compress_type);
        if (ret) {
-               btrfs_drop_extent_cache(inode, start, end, 0);
+               btrfs_drop_extent_map_range(inode, start, end, false);
                goto out_free_reserve;
        }
        btrfs_dec_block_group_reservations(fs_info, ins.objectid);
        }
 
        alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
-       btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
+       btrfs_drop_extent_map_range(inode, start, start + num_bytes - 1, false);
 
        /*
         * Relocation relies on the relocated extents to have exactly the same
                         * skip current ordered extent.
                         */
                        if (ret)
-                               btrfs_drop_extent_cache(inode, start,
-                                               start + ram_size - 1, 0);
+                               btrfs_drop_extent_map_range(inode, start,
+                                                           start + ram_size - 1,
+                                                           false);
                }
 
                btrfs_dec_block_group_reservations(fs_info, ins.objectid);
        return ret;
 
 out_drop_extent_cache:
-       btrfs_drop_extent_cache(inode, start, start + ram_size - 1, 0);
+       btrfs_drop_extent_map_range(inode, start, start + ram_size - 1, false);
 out_reserve:
        btrfs_dec_block_group_reservations(fs_info, ins.objectid);
        btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
                                        1 << BTRFS_ORDERED_PREALLOC,
                                        BTRFS_COMPRESS_NONE);
                        if (ret) {
-                               btrfs_drop_extent_cache(inode, cur_offset,
-                                                       nocow_end, 0);
+                               btrfs_drop_extent_map_range(inode, cur_offset,
+                                                           nocow_end, false);
                                goto error;
                        }
                } else {
                        unwritten_start += logical_len;
                clear_extent_uptodate(io_tree, unwritten_start, end, NULL);
 
-               /* Drop the cache for the part of the extent we didn't write. */
-               btrfs_drop_extent_cache(inode, unwritten_start, end, 0);
+               /* Drop extent maps for the part of the extent we didn't write. */
+               btrfs_drop_extent_map_range(inode, unwritten_start, end, false);
 
                /*
                 * If the ordered extent had an IOERR or something else went
                        if (err)
                                break;
 
-                       btrfs_drop_extent_cache(inode, cur_offset,
-                                               cur_offset + hole_size - 1, 0);
+                       btrfs_drop_extent_map_range(inode, cur_offset,
+                                                   cur_offset + hole_size - 1,
+                                                   false);
                        hole_em = alloc_extent_map();
                        if (!hole_em) {
                                btrfs_set_inode_full_sync(inode);
                                write_unlock(&em_tree->lock);
                                if (err != -EEXIST)
                                        break;
-                               btrfs_drop_extent_cache(inode, cur_offset,
-                                                       cur_offset +
-                                                       hole_size - 1, 0);
+                               btrfs_drop_extent_map_range(inode, cur_offset,
+                                                   cur_offset + hole_size - 1,
+                                                   false);
                        }
                        free_extent_map(hole_em);
                } else {
        if (ret) {
                if (em) {
                        free_extent_map(em);
-                       btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
+                       btrfs_drop_extent_map_range(inode, start,
+                                                   start + len - 1, false);
                }
                em = ERR_PTR(ret);
        }
        }
 
        do {
-               btrfs_drop_extent_cache(inode, em->start,
-                                       em->start + em->len - 1, 0);
+               btrfs_drop_extent_map_range(inode, em->start,
+                                           em->start + em->len - 1, false);
                write_lock(&em_tree->lock);
                ret = add_extent_mapping(em_tree, em, 1);
                write_unlock(&em_tree->lock);
                 * size is not block aligned since we will be keeping the last
                 * block of the extent just the way it is.
                 */
-               btrfs_drop_extent_cache(BTRFS_I(inode),
-                                       ALIGN(new_size, fs_info->sectorsize),
-                                       (u64)-1, 0);
+               btrfs_drop_extent_map_range(BTRFS_I(inode),
+                                           ALIGN(new_size, fs_info->sectorsize),
+                                           (u64)-1, false);
 
                ret = btrfs_truncate_inode_items(trans, root, &control);
 
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 void btrfs_test_destroy_inode(struct inode *inode)
 {
-       btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
+       btrfs_drop_extent_map_range(BTRFS_I(inode), 0, (u64)-1, false);
        kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
 #endif
        }
        btrfs_qgroup_check_reserved_leak(inode);
        inode_tree_del(inode);
-       btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
+       btrfs_drop_extent_map_range(inode, 0, (u64)-1, false);
        btrfs_inode_clear_file_extent_range(inode, 0, (u64)-1);
        btrfs_put_root(inode->root);
 }
                        break;
                }
 
-               btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
-                                       cur_offset + ins.offset -1, 0);
+               btrfs_drop_extent_map_range(BTRFS_I(inode), cur_offset,
+                                           cur_offset + ins.offset - 1, false);
 
                em = alloc_extent_map();
                if (!em) {
                        write_unlock(&em_tree->lock);
                        if (ret != -EEXIST)
                                break;
-                       btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
-                                               cur_offset + ins.offset - 1,
-                                               0);
+                       btrfs_drop_extent_map_range(BTRFS_I(inode), cur_offset,
+                                                   cur_offset + ins.offset - 1,
+                                                   false);
                }
                free_extent_map(em);
 next:
                                       (1 << BTRFS_ORDERED_COMPRESSED),
                                       compression);
        if (ret) {
-               btrfs_drop_extent_cache(inode, start, end, 0);
+               btrfs_drop_extent_map_range(inode, start, end, false);
                goto out_free_reserved;
        }
        btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 
                                if (!ret)
                                        continue;
 
-                               btrfs_drop_extent_cache(BTRFS_I(inode),
-                                               key.offset,     end, 1);
+                               btrfs_drop_extent_map_range(BTRFS_I(inode),
+                                                           key.offset, end, true);
                                unlock_extent(&BTRFS_I(inode)->io_tree,
                                              key.offset, end, NULL);
                        }
 
                /* the lock_extent waits for read_folio to complete */
                lock_extent(&BTRFS_I(inode)->io_tree, start, end, NULL);
-               btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1);
+               btrfs_drop_extent_map_range(BTRFS_I(inode), start, end, true);
                unlock_extent(&BTRFS_I(inode)->io_tree, start, end, NULL);
        }
        return 0;
                        free_extent_map(em);
                        break;
                }
-               btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0);
+               btrfs_drop_extent_map_range(BTRFS_I(inode), start, end, false);
        }
        unlock_extent(&BTRFS_I(inode)->io_tree, start, end, NULL);
        return ret;
 
                goto out;
        }
        free_extent_map(em);
-       btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
+       btrfs_drop_extent_map_range(BTRFS_I(inode), 0, (u64)-1, false);
 
        /*
         * All of the magic numbers are based on the mapping setup in