lkml.org 
[lkml]   [2021]   [Feb]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.4 11/32] btrfs: backref, only search backref entries from leaves of the same root
Date
From: ethanwu <ethanwu@synology.com>

commit cfc0eed0ec89db7c4a8d461174cabfaa4a0912c7 upstream.

We could have some nodes/leaves in subvolume whose owner are not the
that subvolume. In this way, when we resolve normal backrefs of that
subvolume, we should avoid collecting those references from these blocks.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: ethanwu <ethanwu@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/btrfs/backref.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -443,11 +443,14 @@ static int add_all_parents(struct btrfs_
* slot == nritems.
* 2. We are searching for normal backref but bytenr of this leaf
* matches shared data backref
+ * 3. The leaf owner is not equal to the root we are searching
+ *
* For these cases, go to the next leaf before we continue.
*/
eb = path->nodes[0];
if (path->slots[0] >= btrfs_header_nritems(eb) ||
- is_shared_data_backref(preftrees, eb->start)) {
+ is_shared_data_backref(preftrees, eb->start) ||
+ ref->root_id != btrfs_header_owner(eb)) {
if (time_seq == SEQ_LAST)
ret = btrfs_next_leaf(root, path);
else
@@ -466,9 +469,12 @@ static int add_all_parents(struct btrfs_

/*
* We are searching for normal backref but bytenr of this leaf
- * matches shared data backref.
+ * matches shared data backref, OR
+ * the leaf owner is not equal to the root we are searching for
*/
- if (slot == 0 && is_shared_data_backref(preftrees, eb->start)) {
+ if (slot == 0 &&
+ (is_shared_data_backref(preftrees, eb->start) ||
+ ref->root_id != btrfs_header_owner(eb))) {
if (time_seq == SEQ_LAST)
ret = btrfs_next_leaf(root, path);
else

\
 
 \ /
  Last update: 2021-02-05 23:39    [W:0.168 / U:2.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site