4 files changed, 43 insertions, 32 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index fada9c22a021..535cee47fcfb 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3379,11 +3379,13 @@ static int noinline relocate_data_extent(struct inode *reloc_inode,
         struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
         struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
         struct extent_map *em;
+        u64 start = extent_key->objectid - offset;
+        u64 end = start + extent_key->offset - 1;
 
         em = alloc_extent_map(GFP_NOFS);
         BUG_ON(!em || IS_ERR(em));
 
-        em->start = extent_key->objectid - offset;
+        em->start = start;
         em->len = extent_key->offset;
         em->block_len = extent_key->offset;
         em->block_start = extent_key->objectid;
@@ -3391,7 +3393,7 @@ static int noinline relocate_data_extent(struct inode *reloc_inode,
         set_bit(EXTENT_FLAG_PINNED, &em->flags);
 
         /* setup extent map to cheat btrfs_readpage */
-        mutex_lock(&BTRFS_I(reloc_inode)->extent_mutex);
+        lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
         while (1) {
                 int ret;
                 spin_lock(&em_tree->lock);
@@ -3401,13 +3403,11 @@ static int noinline relocate_data_extent(struct inode *reloc_inode,
                         free_extent_map(em);
                         break;
                 }
-                btrfs_drop_extent_cache(reloc_inode, em->start,
-                                        em->start + em->len - 1, 0);
+                btrfs_drop_extent_cache(reloc_inode, start, end, 0);
         }
-        mutex_unlock(&BTRFS_I(reloc_inode)->extent_mutex);
+        unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
 
-        return relocate_inode_pages(reloc_inode, extent_key->objectid - offset,
-                                    extent_key->offset);
+        return relocate_inode_pages(reloc_inode, start, extent_key->offset);
 }
 
 struct btrfs_ref_path {
@@ -3831,7 +3831,6 @@ next:
                          * the file extent item was modified by someone
                          * before the extent got locked.
                          */
-                        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
                         unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
                                       lock_end, GFP_NOFS);
                         extent_locked = 0;
@@ -3896,8 +3895,12 @@ next:
                         lock_start = key.offset;
                         lock_end = lock_start + num_bytes - 1;
                 } else {
-                        BUG_ON(lock_start != key.offset);
-                        BUG_ON(lock_end - lock_start + 1 < num_bytes);
+                        if (lock_start > key.offset ||
+                            lock_end + 1 < key.offset + num_bytes) {
+                                unlock_extent(&BTRFS_I(inode)->io_tree,
+                                              lock_start, lock_end, GFP_NOFS);
+                                extent_locked = 0;
+                        }
                 }
 
                 if (!inode) {
@@ -3951,7 +3954,6 @@ next:
                         if (ordered)
                                 btrfs_put_ordered_extent(ordered);
 
-                        mutex_lock(&BTRFS_I(inode)->extent_mutex);
                         extent_locked = 1;
                         continue;
                 }
@@ -4073,7 +4075,6 @@ next:
                 }
 
                 if (extent_locked) {
-                        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
                         unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
                                       lock_end, GFP_NOFS);
                         extent_locked = 0;
@@ -4091,7 +4092,6 @@ out:
         if (inode) {
                 mutex_unlock(&inode->i_mutex);
                 if (extent_locked) {
-                        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
                         unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
                                       lock_end, GFP_NOFS);
                 }
@@ -4180,10 +4180,8 @@ static int noinline invalidate_extent_cache(struct btrfs_root *root,
 
                 lock_extent(&BTRFS_I(inode)->io_tree, key.offset,
                             key.offset + num_bytes - 1, GFP_NOFS);
-                mutex_lock(&BTRFS_I(inode)->extent_mutex);
                 btrfs_drop_extent_cache(inode, key.offset,
                                         key.offset + num_bytes - 1, 1);
-                mutex_unlock(&BTRFS_I(inode)->extent_mutex);
                 unlock_extent(&BTRFS_I(inode)->io_tree, key.offset,
                               key.offset + num_bytes - 1, GFP_NOFS);
                 cond_resched();
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 7503bd46819b..65a0583027e9 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -946,8 +946,12 @@ int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
 
         err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1,
                              &failed_start, mask);
-        if (err == -EEXIST)
+        if (err == -EEXIST) {
+                if (failed_start > start)
+                        clear_extent_bit(tree, start, failed_start - 1,
+                                         EXTENT_LOCKED, 1, 0, mask);
                 return 0;
+        }
         return 1;
 }
 EXPORT_SYMBOL(try_lock_extent);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b8a7637e14a1..1a0510ad030c 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -364,6 +364,7 @@ int noinline btrfs_drop_extents(struct btrfs_trans_handle *trans,
                        u64 start, u64 end, u64 inline_limit, u64 *hint_byte)
 {
         u64 extent_end = 0;
+        u64 locked_end = end;
         u64 search_start = start;
         u64 leaf_start;
         u64 ram_bytes = 0;
@@ -479,12 +480,6 @@ next_slot:
                         goto next_slot;
                 }
 
-                if (found_inline) {
-                        u64 mask = root->sectorsize - 1;
-                        search_start = (extent_end + mask) & ~mask;
-                } else
-                        search_start = extent_end;
-
                 if (end <= extent_end && start >= key.offset && found_inline)
                         *hint_byte = EXTENT_MAP_INLINE;
 
@@ -501,6 +496,26 @@ next_slot:
                         if (found_inline && start <= key.offset)
                                 keep = 1;
                 }
+
+                if (bookend && found_extent && locked_end < extent_end) {
+                        ret = try_lock_extent(&BTRFS_I(inode)->io_tree,
+                                        locked_end, extent_end - 1, GFP_NOFS);
+                        if (!ret) {
+                                btrfs_release_path(root, path);
+                                lock_extent(&BTRFS_I(inode)->io_tree,
+                                        locked_end, extent_end - 1, GFP_NOFS);
+                                locked_end = extent_end;
+                                continue;
+                        }
+                        locked_end = extent_end;
+                }
+
+                if (found_inline) {
+                        u64 mask = root->sectorsize - 1;
+                        search_start = (extent_end + mask) & ~mask;
+                } else
+                        search_start = extent_end;
+
                 /* truncate existing extent */
                 if (start > key.offset) {
                         u64 new_num;
@@ -638,6 +653,10 @@ next_slot:
         }
 out:
         btrfs_free_path(path);
+        if (locked_end > end) {
+                unlock_extent(&BTRFS_I(inode)->io_tree, end, locked_end - 1,
+                              GFP_NOFS);
+        }
         btrfs_check_file(root, inode);
         return ret;
 }
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8254d6fa6910..e8511d14b119 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -246,7 +246,6 @@ static int cow_file_range_inline(struct btrfs_trans_handle *trans,
                 return 1;
         }
 
-        mutex_lock(&BTRFS_I(inode)->extent_mutex);
         ret = btrfs_drop_extents(trans, root, inode, start,
                                  aligned_end, aligned_end, &hint_byte);
         BUG_ON(ret);
@@ -258,7 +257,6 @@ static int cow_file_range_inline(struct btrfs_trans_handle *trans,
                                    compressed_pages);
         BUG_ON(ret);
         btrfs_drop_extent_cache(inode, start, aligned_end, 0);
-        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
         return 0;
 }
 
@@ -437,9 +435,7 @@ again:
         BUG_ON(disk_num_bytes >
                btrfs_super_total_bytes(&root->fs_info->super_copy));
 
-        mutex_lock(&BTRFS_I(inode)->extent_mutex);
         btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
-        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 
         while(disk_num_bytes > 0) {
                 unsigned long min_bytes;
@@ -477,8 +473,6 @@ again:
                 em->block_start = ins.objectid;
                 em->block_len = ins.offset;
                 em->bdev = root->fs_info->fs_devices->latest_bdev;
-
-                mutex_lock(&BTRFS_I(inode)->extent_mutex);
                 set_bit(EXTENT_FLAG_PINNED, &em->flags);
 
                 if (will_compress)
@@ -495,7 +489,6 @@ again:
                         btrfs_drop_extent_cache(inode, start,
                                                 start + ram_size - 1, 0);
                 }
-                mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 
                 cur_alloc_size = ins.offset;
                 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
@@ -1016,8 +1009,6 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 
         INIT_LIST_HEAD(&list);
 
-        mutex_lock(&BTRFS_I(inode)->extent_mutex);
-
         ret = btrfs_drop_extents(trans, root, inode,
                                  ordered_extent->file_offset,
                                  ordered_extent->file_offset +
@@ -1059,7 +1050,6 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         btrfs_drop_extent_cache(inode, ordered_extent->file_offset,
                                 ordered_extent->file_offset +
                                 ordered_extent->len - 1, 0);
-        mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 
         ins.objectid = ordered_extent->start;
         ins.offset = ordered_extent->disk_len;