diff options
| author | Qu Wenruo <wqu@suse.com> | 2017-11-22 17:03:22 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2018-01-03 17:09:20 +0100 |
| commit | 0ad4f36bf387e3513b0401eed7abeda7bbffe4e1 (patch) | |
| tree | 15b190048b57a30617b83e9c99917f15beba14af /cmds-check.c | |
| parent | 77d47b4a3d304e52fd222c4bd21f9306e83037ac (diff) | |
btrfs-progs: lowmem check: Fix false alerts for image with shared block ref only backref
[BUG]
For image with shared block ref only metadata item like:
------
item 66 key (21573632 METADATA_ITEM 0) itemoff 3971 itemsize 24
refs 66 gen 9 flags TREE_BLOCK|FULL_BACKREF
tree block skinny level 0
item 0 key (21573632 SHARED_BLOCK_REF 21676032) itemoff 3995 itemsize 0
shared block backref
item 1 key (21573632 SHARED_BLOCK_REF 21921792) itemoff 3995 itemsize 0
shared block backref
item 2 key (21573632 SHARED_BLOCK_REF 21995520) itemoff 3995 itemsize 0
shared block backref
item 3 key (21573632 SHARED_BLOCK_REF 22077440) itemoff 3995 itemsize 0
shared block backref
...
------
Lowmem mode check will report false alerts like:
------
ERROR: extent[21573632 4096] backref lost (owner: 256, level: 0)
------
[CAUSE]
In fact, the false alerts are not even from extent tree verfication, but
a fs tree helper which is designed to make sure there is some tree block
referring to the fs tree block.
The idea is to find inlined tree backref then keyed TREE_BLOCK_REF_KEY.
However it missed SHARED_BLOCK_REF_KEY, and caused such false alert.
[FIX]
Add SHARED_BLOCK_REF_KEY to make the warning shut up.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'cmds-check.c')
| -rw-r--r-- | cmds-check.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/cmds-check.c b/cmds-check.c index 7eb08b6c..791fab6b 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -11850,6 +11850,30 @@ static int check_tree_block_ref(struct btrfs_root *root, if (!ret) found_ref = 1; } + /* + * Finally check SHARED BLOCK REF, any found will be good + * Here we're not doing comprehensive extent backref checking, + * only need to ensure there is some extent referring to this + * tree block. + */ + if (!found_ref) { + btrfs_release_path(&path); + key.objectid = bytenr; + key.type = BTRFS_SHARED_BLOCK_REF_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0); + if (ret < 0) { + err |= BACKREF_MISSING; + goto out; + } + ret = btrfs_previous_extent_item(extent_root, &path, bytenr); + if (ret) { + err |= BACKREF_MISSING; + goto out; + } + found_ref = 1; + } if (!found_ref) err |= BACKREF_MISSING; out: |