diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2013-07-13 00:40:35 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-08-02 22:14:55 +0200 |
| commit | 07b6cb2dd21301a73441a3098514fe44df9caf78 (patch) | |
| tree | 8fa5e973b881d47f805fed9c5b88ecb21f803804 /fs | |
| parent | 7f9fd38136b10b94338a9ae1b2d14830f444974e (diff) | |
ext4: don't allow ext4_free_blocks() to fail due to ENOMEM
commit e7676a704ee0a1ef71a6b23760b5a8f6896cb1a1 upstream.
The filesystem should not be marked inconsistent if ext4_free_blocks()
is not able to allocate memory. Unfortunately some callers (most
notably ext4_truncate) don't have a way to reflect an error back up to
the VFS. And even if we did, most userspace applications won't deal
with most system calls returning ENOMEM anyway.
Reported-by: Nagachandra P <nagachandra@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/mballoc.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 9243103c86fc..9b8c131ffa5a 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4696,11 +4696,16 @@ do_more: * blocks being freed are metadata. these blocks shouldn't * be used until this transaction is committed */ + retry: new_entry = kmem_cache_alloc(ext4_free_ext_cachep, GFP_NOFS); if (!new_entry) { - ext4_mb_unload_buddy(&e4b); - err = -ENOMEM; - goto error_return; + /* + * We use a retry loop because + * ext4_free_blocks() is not allowed to fail. + */ + cond_resched(); + congestion_wait(BLK_RW_ASYNC, HZ/50); + goto retry; } new_entry->start_cluster = bit; new_entry->group = block_group; |