In check_extent_data_item(), after checking extent item of one data extent, we search inlined data backref, then EXTENT_DATA_REF_KEY.
But we didn't search SHARED_DATA_REF, so if the backref is SHARED_DATA_REF, then we will raise a false alert about backref lost. Fix by also checking SHARED_DATA_REF_KEY in check_extent_data_item(). Reported-by: Chris Murphy <[email protected]> Signed-off-by: Qu Wenruo <[email protected]> --- cmds-check.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) diff --git a/cmds-check.c b/cmds-check.c index 5cc84690..17b7efbf 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -10229,10 +10229,8 @@ static int check_extent_data_item(struct btrfs_root *root, dbref_key.offset = btrfs_file_extent_disk_num_bytes(eb, fi); ret = btrfs_search_slot(NULL, extent_root, &dbref_key, &path, 0, 0); - if (ret) { - err |= BACKREF_MISSING; - goto error; - } + if (ret) + goto out; leaf = path.nodes[0]; slot = path.slots[0]; @@ -10273,11 +10271,10 @@ static int check_extent_data_item(struct btrfs_root *root, ptr += btrfs_extent_inline_ref_size(type); } - /* Didn't found inlined data backref, try EXTENT_DATA_REF_KEY */ if (!found_dbackref) { btrfs_release_path(&path); - btrfs_init_path(&path); + /* Didn't find inlined data backref, try EXTENT_DATA_REF_KEY */ dbref_key.objectid = btrfs_file_extent_disk_bytenr(eb, fi); dbref_key.type = BTRFS_EXTENT_DATA_REF_KEY; dbref_key.offset = hash_extent_data_ref(root->objectid, @@ -10285,13 +10282,32 @@ static int check_extent_data_item(struct btrfs_root *root, ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &dbref_key, &path, 0, 0); - if (!ret) + if (!ret) { found_dbackref = 1; + goto out; + } + + btrfs_release_path(&path); + + /* + * Neither inlined nor EXTENT_DATA_REF found, try + * SHARED_DATA_REF as last chance. + */ + dbref_key.objectid = disk_bytenr; + dbref_key.type = BTRFS_SHARED_DATA_REF_KEY; + dbref_key.offset = eb->start; + + ret = btrfs_search_slot(NULL, root->fs_info->extent_root, + &dbref_key, &path, 0, 0); + if (!ret) { + found_dbackref = 1; + goto out; + } } +out: if (!found_dbackref) err |= BACKREF_MISSING; -error: btrfs_release_path(&path); if (err & BACKREF_MISSING) { error("data extent[%llu %llu] backref lost", -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
