ext4: prevent ext4_quota_write() from failing due to ENOSPC
In order to prevent quota block tracking to be inaccurate when
ext4_quota_write() fails with ENOSPC, we make two changes. The quota
file can now use the reserved block (since the quota file is arguably
file system metadata), and ext4_quota_write() now uses
ext4_should_retry_alloc() to retry the block allocation after a commit
has completed and released some blocks for allocation.
This fixes failures of xfstests generic/270:
Quota error (device vdc): write_blk: dquota write failed
Quota error (device vdc): qtree_write_dquot: Error -28 occurred while creating quota
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 9588240..9962d57 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -576,6 +576,8 @@
ar.flags = EXT4_MB_HINT_DATA;
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
ar.flags |= EXT4_MB_DELALLOC_RESERVED;
+ if (flags & EXT4_GET_BLOCKS_METADATA_NOFAIL)
+ ar.flags |= EXT4_MB_USE_RESERVED;
ar.goal = ext4_find_goal(inode, map->m_lblk, partial);