diff options
author | Hannes Reinecke <hare@suse.de> | 2015-11-26 08:46:57 +0100 |
---|---|---|
committer | Jens Axboe <axboe@fb.com> | 2015-11-29 14:37:27 -0700 |
commit | bf4e6b4e757488dee1b6a581f49c7ac34cd217f8 (patch) | |
tree | 95e32c168d7478d0f541b5d19d1edf0e3d1160f1 /block | |
parent | d0a712ceb83ebaea32d520825ee7b997f59b168f (diff) | |
download | linux-bf4e6b4e757488dee1b6a581f49c7ac34cd217f8.tar.bz2 |
block: Always check queue limits for cloned requests
When a cloned request is retried on other queues it always needs
to be checked against the queue limits of that queue.
Otherwise the calculations for nr_phys_segments might be wrong,
leading to a crash in scsi_init_sgtable().
To clarify this the patch renames blk_rq_check_limits()
to blk_cloned_rq_check_limits() and removes the symbol
export, as the new function should only be used for
cloned requests and never exported.
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Ewan Milne <emilne@redhat.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Fixes: e2a60da74 ("block: Clean up special command handling logic")
Cc: stable@vger.kernel.org # 3.7+
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/blk-core.c | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 5131993b23a1..a0af4043dda2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2114,7 +2114,8 @@ blk_qc_t submit_bio(int rw, struct bio *bio) EXPORT_SYMBOL(submit_bio); /** - * blk_rq_check_limits - Helper function to check a request for the queue limit + * blk_cloned_rq_check_limits - Helper function to check a cloned request + * for new the queue limits * @q: the queue * @rq: the request being checked * @@ -2125,20 +2126,13 @@ EXPORT_SYMBOL(submit_bio); * after it is inserted to @q, it should be checked against @q before * the insertion using this generic function. * - * This function should also be useful for request stacking drivers - * in some cases below, so export this function. * Request stacking drivers like request-based dm may change the queue - * limits while requests are in the queue (e.g. dm's table swapping). - * Such request stacking drivers should check those requests against - * the new queue limits again when they dispatch those requests, - * although such checkings are also done against the old queue limits - * when submitting requests. + * limits when retrying requests on other queues. Those requests need + * to be checked against the new queue limits again during dispatch. */ -int blk_rq_check_limits(struct request_queue *q, struct request *rq) +static int blk_cloned_rq_check_limits(struct request_queue *q, + struct request *rq) { - if (!rq_mergeable(rq)) - return 0; - if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, rq->cmd_flags)) { printk(KERN_ERR "%s: over max size limit.\n", __func__); return -EIO; @@ -2158,7 +2152,6 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq) return 0; } -EXPORT_SYMBOL_GPL(blk_rq_check_limits); /** * blk_insert_cloned_request - Helper for stacking drivers to submit a request @@ -2170,7 +2163,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq) unsigned long flags; int where = ELEVATOR_INSERT_BACK; - if (blk_rq_check_limits(q, rq)) + if (blk_cloned_rq_check_limits(q, rq)) return -EIO; if (rq->rq_disk && |