kernel/linux.git/include/linux/blk-mq.h, branch v6.1.175

blk-mq: fix potential io hang by wrong 'wake_batch'

2023-07-19T14:20:55+00:00

[ Upstream commit 4f1731df60f9033669f024d06ae26a6301260b55 ] In __blk_mq_tag_busy/idle(), updating 'active_queues' and calculating 'wake_batch' is not atomic: t1: t2: _blk_mq_tag_busy blk_mq_tag_busy inc active_queues // assume 1->2 inc active_queues // 2 -> 3 blk_mq_update_wake_batch // calculate based on 3 blk_mq_update_wake_batch /* calculate based on 2, while active_queues is actually 3. */ Fix this problem by protecting them wih 'tags->lock', this is not a hot path, so performance should not be concerned. And now that all writers are inside the lock, switch 'actives_queues' from atomic to unsigned int. Fixes: 180dccb0dba4 ("blk-mq: fix tag_get wait task can't be awakened") Signed-off-by: Yu Kuai Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20230610023043.2559121-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: do not reverse request order when flushing plug list

2023-03-22T12:33:46+00:00

[ Upstream commit 34e0a279a993debaff03158fc2fbf6a00c093643 ] Commit 26fed4ac4eab ("block: flush plug based on hardware and software queue order") changed flushing of plug list to submit requests one device at a time. However while doing that it also started using list_add_tail() instead of list_add() used previously thus effectively submitting requests in reverse order. Also when forming a rq_list with remaining requests (in case two or more devices are used), we effectively reverse the ordering of the plug list for each device we process. Submitting requests in reverse order has negative impact on performance for rotational disks (when BFQ is not in use). We observe 10-25% regression in random 4k write throughput, as well as ~20% regression in MariaDB OLTP benchmark on rotational storage on btrfs filesystem. Fix the problem by preserving ordering of the plug list when inserting requests into the queuelist as well as by appending to requeue_list instead of prepending to it. Fixes: 26fed4ac4eab ("block: flush plug based on hardware and software queue order") Signed-off-by: Jan Kara Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230313093002.11756-1-jack@suse.cz Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

blk-mq: don't add non-pt request with ->end_io to batch

2022-10-27T13:15:44+00:00

dm-rq implements ->end_io callback for request issued to underlying queue, and it isn't passthrough request. Commit ab3e1d3bbab9 ("block: allow end_io based requests in the completion batch handling") doesn't clear rq->bio and rq->__data_len for request with ->end_io in blk_mq_end_request_batch(), and this way is actually dangerous, but so far it is only for nvme passthrough request. dm-rq needs to clean up remained bios in case of partial completion, and req->bio is required, then use-after-free is triggered, so the underlying clone request can't be completed in blk_mq_end_request_batch. Fix panic by not adding such request into batch list, and the issue can be triggered simply by exposing nvme pci to dm-mpath simply. Fixes: ab3e1d3bbab9 ("block: allow end_io based requests in the completion batch handling") Cc: dm-devel@redhat.com Cc: Mike Snitzer Reported-by: Changhui Zhong Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20221027085709.513175-1-ming.lei@redhat.com Signed-off-by: Jens Axboe

block: add blk_rq_map_user_io

2022-09-30T13:51:13+00:00

Create a helper blk_rq_map_user_io for mapping of vectored as well as non-vectored requests. This will help in saving dupilcation of code at few places in scsi and nvme. Signed-off-by: Anuj Gupta Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20220930062749.152261-4-anuj20.g@samsung.com Signed-off-by: Jens Axboe

block: allow end_io based requests in the completion batch handling

2022-09-30T13:49:11+00:00

With end_io handlers now being able to potentially pass ownership of the request upon completion, we can allow requests with end_io handlers in the batch completion handling. Reviewed-by: Anuj Gupta Reviewed-by: Keith Busch Co-developed-by: Stefan Roesch Signed-off-by: Jens Axboe

block: change request end_io handler to pass back a return value

2022-09-30T13:49:09+00:00

Everything is just converted to returning RQ_END_IO_NONE, and there should be no functional changes with this patch. In preparation for allowing the end_io handler to pass ownership back to the block layer, rather than retain ownership of the request. Reviewed-by: Keith Busch Signed-off-by: Jens Axboe

Merge branch 'for-6.1/io_uring' into for-6.1/passthrough

2022-09-30T13:47:42+00:00

* for-6.1/io_uring: (56 commits) io_uring/net: fix notif cqe reordering io_uring/net: don't update msg_name if not provided io_uring: don't gate task_work run on TIF_NOTIFY_SIGNAL io_uring/rw: defer fsnotify calls to task context io_uring/net: fix fast_iov assignment in io_setup_async_msg() io_uring/net: fix non-zc send with address io_uring/net: don't skip notifs for failed requests io_uring/rw: don't lose short results on io_setup_async_rw() io_uring/rw: fix unexpected link breakage io_uring/net: fix cleanup double free free_iov init io_uring: fix CQE reordering io_uring/net: fix UAF in io_sendrecv_fail() selftest/net: adjust io_uring sendzc notif handling io_uring: ensure local task_work marks task as running io_uring/net: zerocopy sendmsg io_uring/net: combine fail handlers io_uring/net: rename io_sendzc() io_uring/net: support non-zerocopy sendto io_uring/net: refactor io_setup_async_addr io_uring/net: don't lose partial send_zc on fail ...

block: export blk_rq_is_poll

2022-09-21T16:30:42+00:00

This is in preparation to support iopoll for nvme passthrough. Signed-off-by: Kanchan Joshi Link: https://lore.kernel.org/r/20220823161443.49436-4-joshi.k@samsung.com Signed-off-by: Jens Axboe

block: Fix the enum blk_eh_timer_return documentation

2022-09-21T14:34:37+00:00

The documentation of the blk_eh_timer_return enumeration values does not reflect correctly how e.g. the SCSI core uses these values. Fix the documentation. Cc: Christoph Hellwig Cc: Ming Lei Cc: Hannes Reinecke Cc: Damien Le Moal Cc: Johannes Thumshirn Fixes: 88b0cfad2888 ("block: document the blk_eh_timer_return values") Signed-off-by: Bart Van Assche Reviewed-by: Johannes Thumshirn Reviewed-by: Damien Le Moal Link: https://lore.kernel.org/r/20220920200626.3422296-1-bvanassche@acm.org Signed-off-by: Jens Axboe

block: shrink rq_map_data a bit

2022-08-22T16:07:56+00:00

We don't need full ints for several of these members. Change the page_order and nr_entries to unsigned shorts, and the true/false from_user and null_mapped to booleans. This shrinks the struct from 32 to 24 bytes on 64-bit archs. Reviewed-by: Chaitanya Kulkarni Signed-off-by: Jens Axboe