diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/backref.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 94a3c6deafbb..232f49415ab9 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -140,6 +140,7 @@ struct share_check { struct btrfs_root *root; u64 inum; u64 data_bytenr; + u64 data_extent_gen; /* * Counts number of inodes that refer to an extent (different inodes in * the same root or different roots) that we could find. The sharedness @@ -1481,6 +1482,21 @@ again: */ if (sc && bytenr == sc->data_bytenr) { /* + * If our data extent is from a generation more recent than the + * last generation used to snapshot the root, then we know that + * it can not be shared through subtrees, so we can skip + * resolving indirect references, there's no point in + * determining the extent buffers for the path from the fs tree + * root node down to the leaf that has the file extent item that + * points to the data extent. + */ + if (sc->data_extent_gen > + btrfs_root_last_snapshot(&sc->root->root_item)) { + ret = BACKREF_FOUND_NOT_SHARED; + goto out; + } + + /* * If we are only determining if a data extent is shared or not * and the corresponding file extent item is located in the same * leaf as the previous file extent item, we can skip resolving @@ -1789,6 +1805,7 @@ int btrfs_is_data_extent_shared(struct btrfs_inode *inode, u64 bytenr, .root = root, .inum = btrfs_ino(inode), .data_bytenr = bytenr, + .data_extent_gen = extent_gen, .share_count = 0, .self_ref_count = 0, .have_delayed_delete_refs = false, @@ -1836,17 +1853,6 @@ int btrfs_is_data_extent_shared(struct btrfs_inode *inode, u64 bytenr, if (ret < 0 && ret != -ENOENT) break; ret = 0; - /* - * If our data extent is not shared through reflinks and it was - * created in a generation after the last one used to create a - * snapshot of the inode's root, then it can not be shared - * indirectly through subtrees, as that can only happen with - * snapshots. In this case bail out, no need to check for the - * sharedness of extent buffers. - */ - if (level == -1 && - extent_gen > btrfs_root_last_snapshot(&root->root_item)) - break; /* * If our data extent was not directly shared (without multiple |