xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Btrfs: update backrefs while dropping snapshot

Browse Source 
The new backref format has restriction on type of backref item.  If a tree
block isn't referenced by its owner tree, full backrefs must be used for the
pointers in it. When a tree block loses its owner tree's reference, backrefs
for the pointers in it should be updated to full backrefs. Current
btrfs_drop_snapshot misses the code that updates backrefs, so it's unsafe for
general use.

This patch adds backrefs update code to btrfs_drop_snapshot.  It isn't a
problem in the restricted form btrfs_drop_snapshot is used today, but for
general snapshot deletion this update is required.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Yan Zheng
2009-06-27 21:07:35 -04:00
committed by Chris Mason
parent a970b0a16c
commit 2c47e605a9
4 changed files with 400 additions and 186 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
fs/btrfs/relocation.c
View File

@@ -1788,7 +1788,7 @@ static void merge_func(struct btrfs_work *work)
btrfs_end_transaction(trans, root);
}
btrfs_drop_dead_root(reloc_root);
btrfs_drop_snapshot(reloc_root, 0);
if (atomic_dec_and_test(async->num_pending))
complete(async->done);
@@ -2075,9 +2075,6 @@ static int do_relocation(struct btrfs_trans_handle *trans,
ret = btrfs_drop_subtree(trans, root, eb, upper->eb);
BUG_ON(ret);
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
}
if (!lowest) {
btrfs_tree_unlock(upper->eb);