1 files changed, 25 insertions, 15 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8edcdf6910f7..4d7c02258390 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1641,7 +1641,7 @@ static void btrfs_clear_bit_hook(struct inode *inode,
                         btrfs_delalloc_release_metadata(inode, len);
 
                 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
-                    && do_list)
+                    && do_list && !(state->state & EXTENT_NORESERVE))
                         btrfs_free_reserved_data_space(inode, len);
 
                 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len,
@@ -6396,10 +6396,10 @@ out:
  * returns 1 when the nocow is safe, < 1 on error, 0 if the
  * block must be cow'd
  */
-static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
-                                      struct inode *inode, u64 offset, u64 *len,
-                                      u64 *orig_start, u64 *orig_block_len,
-                                      u64 *ram_bytes)
+noinline int can_nocow_extent(struct btrfs_trans_handle *trans,
+                              struct inode *inode, u64 offset, u64 *len,
+                              u64 *orig_start, u64 *orig_block_len,
+                              u64 *ram_bytes)
 {
         struct btrfs_path *path;
         int ret;
@@ -6413,7 +6413,7 @@ static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
         u64 num_bytes;
         int slot;
         int found_type;
-
+        bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
         path = btrfs_alloc_path();
         if (!path)
                 return -ENOMEM;
@@ -6453,18 +6453,28 @@ static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
                 /* not a regular extent, must cow */
                 goto out;
         }
+
+        if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
+                goto out;
+
         disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
+        if (disk_bytenr == 0)
+                goto out;
+
+        if (btrfs_file_extent_compression(leaf, fi) ||
+            btrfs_file_extent_encryption(leaf, fi) ||
+            btrfs_file_extent_other_encoding(leaf, fi))
+                goto out;
+
         backref_offset = btrfs_file_extent_offset(leaf, fi);
 
-        *orig_start = key.offset - backref_offset;
-        *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
-        *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
+        if (orig_start) {
+                *orig_start = key.offset - backref_offset;
+                *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
+                *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
+        }
 
         extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
-        if (extent_end < offset + *len) {
-                /* extent doesn't include our full range, must cow */
-                goto out;
-        }
 
         if (btrfs_extent_readonly(root, disk_bytenr))
                 goto out;
@@ -6708,8 +6718,8 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
                 if (IS_ERR(trans))
                         goto must_cow;
 
-                if (can_nocow_odirect(trans, inode, start, &len, &orig_start,
-                                      &orig_block_len, &ram_bytes) == 1) {
+                if (can_nocow_extent(trans, inode, start, &len, &orig_start,
+                                     &orig_block_len, &ram_bytes) == 1) {
                         if (type == BTRFS_ORDERED_PREALLOC) {
                                 free_extent_map(em);
                                 em = create_pinned_em(inode, start, len,