linux/block, branch v3.19

blk-mq: release mq's kobjects in blk_release_queue()

2015-01-29T16:30:51Z

The kobject memory inside blk-mq hctx/ctx shouldn't have been freed before the kobject is released because driver core can access it freely before its release. We can't do that in all ctx/hctx/mq_kobj's release handler because it can be run before blk_cleanup_queue(). Given mq_kobj shouldn't have been introduced, this patch simply moves mq's release into blk_release_queue(). Reported-by: Sasha Levin Signed-off-by: Ming Lei Signed-off-by: Jens Axboe

Revert "blk-mq: fix hctx/ctx kobject use-after-free"

2015-01-29T16:30:49Z

This reverts commit 76d697d10769048e5721510100bf3a9413a56385. The commit 76d697d10769048 causes general protection fault reported from Bart Van Assche: https://lkml.org/lkml/2015/1/28/334 Reported-by: Bart Van Assche Signed-off-by: Ming Lei Signed-off-by: Jens Axboe

blk-mq: fix hctx/ctx kobject use-after-free

2015-01-20T16:28:33Z

The kobject memory shouldn't have been freed before the kobject is released because driver core can access it freely before its release. This patch frees hctx in its release callback. For ctx, they share one single per-cpu variable which is associated with the request queue, so free ctx in q->mq_kobj's release handler. Signed-off-by: Sasha Levin (fix ctx kobjects) Signed-off-by: Ming Lei Signed-off-by: Jens Axboe

blk-mq: End unstarted requests on a dying queue

2015-01-08T15:59:53Z

Requests that haven't been started prior to a queue dying can be ended in error without waiting for them to start and time out. Signed-off-by: Keith Busch Added code comment to explain why this is done. Signed-off-by: Jens Axboe

blk-mq: Allow requests to never expire

2015-01-08T15:59:01Z

Some types of requests may be started that are not gauranteed to ever complete. This adds a request flag that a driver can use so mark the request as such. Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

blk-mq: Add helper to abort requeued requests

2015-01-08T15:55:53Z

Adds a helper function a driver can use to abort requeued requests in case any are pending when h/w queues are being removed. Signed-off-by: Jens Axboe

blk-mq: Let drivers cancel requeue_work

2015-01-08T15:55:40Z

Kicking requeued requests will start h/w queues in a work_queue, which may alter the driver's requested state to temporarily stop them. This patch exports a method to cancel the q->requeue_work so a driver can be assured stopped h/w queues won't be started up before it is ready. Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

blk-mq: Export if requests were started

2015-01-08T15:55:27Z

Drivers can iterate over all allocated request tags, but their callback needs a way to know if the driver started the request in the first place. Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

blk-mq: Wake tasks entering queue on dying

2015-01-08T15:53:56Z

When the queue is set to dying, wake up tasks that are waiting on frozen queue so they realize it is dying and abandon their request. Signed-off-by: Keith Busch Modified by me to add a code comment on the need for the wakeup. Signed-off-by: Jens Axboe

blk-mq: get rid of ->cmd_size in the hardware queue

2015-01-07T17:44:04Z

We store it in the tag set, we don't need it in the hardware queue. While removing cmd_size, place ->queue_num further down to avoid a hole on 64-bit archs. It's not used in any fast paths, so we can safely move it. Signed-off-by: Jens Axboe