From b844167edc7fcafda9623955c05e4c1b3c32ebc7 Mon Sep 17 00:00:00 2001 From: Curt Wohlgemuth Date: Tue, 8 Dec 2009 22:18:25 -0500 Subject: [PATCH] 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 Acked-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index ab2dad1dfb7..19635c34199 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -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);