leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ext4: don't allow ext4_free_blocks() to fail due to ENOMEM

Browse Source 
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>
Cc: stable@vger.kernel.org
This commit is contained in:
Theodore Ts'o 2013-07-13 00:40:35 -04:00
parent bdafe42aaf
commit e7676a704e
1 changed files with 8 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
fs/ext4/mballoc.c
View File

@ -4740,11 +4740,16 @@ 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_data_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->efd_start_cluster = bit;
new_entry->efd_group = block_group;