ext4: remove blocks from inode prealloc list on failure

This fixes a leak of blocks in an inode prealloc list if device failures
cause ext4_mb_mark_diskspace_used() to fail.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Curt Wohlgemuth 2009-12-08 22:18:25 -05:00 committed by Theodore Ts'o
parent d4edac314e
commit b844167edc

View file

@ -3010,6 +3010,24 @@ static void ext4_mb_collect_stats(struct ext4_allocation_context *ac)
trace_ext4_mballoc_prealloc(ac);
}
/*
* Called on failure; free up any blocks from the inode PA for this
* context. We don't need this for MB_GROUP_PA because we only change
* pa_free in ext4_mb_release_context(), but on failure, we've already
* zeroed out ac->ac_b_ex.fe_len, so group_pa->pa_free is not changed.
*/
static void ext4_discard_allocated_blocks(struct ext4_allocation_context *ac)
{
struct ext4_prealloc_space *pa = ac->ac_pa;
int len;
if (pa && pa->pa_type == MB_INODE_PA) {
len = ac->ac_b_ex.fe_len;
pa->pa_free += len;
}
}
/*
* use blocks preallocated to inode
*/
@ -4295,6 +4313,7 @@ repeat:
ac->ac_status = AC_STATUS_CONTINUE;
goto repeat;
} else if (*errp) {
ext4_discard_allocated_blocks(ac);
ac->ac_b_ex.fe_len = 0;
ar->len = 0;
ext4_mb_show_ac(ac);