blk-mq: cleanup after blk_mq_init_rq_map failures

In blk-mq.c blk_mq_alloc_tag_set, if:
	set->tags = kmalloc_node()
succeeds, but one of the blk_mq_init_rq_map() calls fails,
	goto out_unwind;
needs to free set->tags so the caller is not obligated
to do so.  None of the current callers (null_blk,
virtio_blk, virtio_blk, or the forthcoming scsi-mq)
do so.

set->tags needs to be set to NULL after doing so,
so other tag cleanup logic doesn't try to free
a stale pointer later.  Also set it to NULL
in blk_mq_free_tag_set.

Tested with error injection on the forthcoming
scsi-mq + hpsa combination.

Signed-off-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Robert Elliott 2014-09-02 11:38:44 -05:00 committed by Jens Axboe
parent dc501dc0d9
commit 5676e7b6db

View File

@ -1982,6 +1982,8 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
out_unwind:
while (--i >= 0)
blk_mq_free_rq_map(set, set->tags[i], i);
kfree(set->tags);
set->tags = NULL;
out:
return -ENOMEM;
}
@ -1997,6 +1999,7 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set)
}
kfree(set->tags);
set->tags = NULL;
}
EXPORT_SYMBOL(blk_mq_free_tag_set);