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2022-10-28blk-mq: Properly init requests from blk_mq_alloc_request_hctx()John Garry
Function blk_mq_alloc_request_hctx() is missing zeroing/init of rq->bio, biotail, __sector, and __data_len members, which blk_mq_alloc_request() has, so duplicate what we do in blk_mq_alloc_request(). Fixes: 1f5bd336b9150 ("blk-mq: add blk_mq_alloc_request_hctx") Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/1666780513-121650-1-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-25blk-mq: move the call to blk_put_queue out of blk_mq_destroy_queueChristoph Hellwig
The fact that blk_mq_destroy_queue also drops a queue reference leads to various places having to grab an extra reference. Move the call to blk_put_queue into the callers to allow removing the extra references. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20221018135720.670094-2-hch@lst.de [axboe: fix fabrics_q vs admin_q conflict in nvme core.c] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-23block: fix up elevator_type refcountingJinlong Chen
The current reference management logic of io scheduler modules contains refcnt problems. For example, blk_mq_init_sched may fail before or after the calling of e->ops.init_sched. If it fails before the calling, it does nothing to the reference to the io scheduler module. But if it fails after the calling, it releases the reference by calling kobject_put(&eq->kobj). As the callers of blk_mq_init_sched can't know exactly where the failure happens, they can't handle the reference to the io scheduler module properly: releasing the reference on failure results in double-release if blk_mq_init_sched has released it, and not releasing the reference results in ghost reference if blk_mq_init_sched did not release it either. The same problem also exists in io schedulers' init_sched implementations. We can address the problem by adding releasing statements to the error handling procedures of blk_mq_init_sched and init_sched implementations. But that is counterintuitive and requires modifications to existing io schedulers. Instead, We make elevator_alloc get the io scheduler module references that will be released by elevator_release. And then, we match each elevator_get with an elevator_put. Therefore, each reference to an io scheduler module explicitly has its own getter and releaser, and we no longer need to worry about the refcnt problems. The bugs and the patch can be validated with tools here: https://github.com/nickyc975/linux_elv_refcnt_bug.git [hch: split out a few bits into separate patches, use a non-try module_get in elevator_alloc] Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20221020064819.1469928-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-23block: add proper helpers for elevator_type module refcount managementChristoph Hellwig
Make sure we have helpers for all relevant module refcount operations on the elevator_type in elevator.h, and use them. Move the call to the get helper in blk_mq_elv_switch_none a bit so that it is obvious with a less verbose comment. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20221020064819.1469928-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16blk-mq: fix null pointer dereference in blk_mq_clear_rq_mapping()Yu Kuai
Our syzkaller report a null pointer dereference, root cause is following: __blk_mq_alloc_map_and_rqs set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs blk_mq_alloc_map_and_rqs blk_mq_alloc_rqs // failed due to oom alloc_pages_node // set->tags[hctx_idx] is still NULL blk_mq_free_rqs drv_tags = set->tags[hctx_idx]; // null pointer dereference is triggered blk_mq_clear_rq_mapping(drv_tags, ...) This is because commit 63064be150e4 ("blk-mq: Add blk_mq_alloc_map_and_rqs()") merged the two steps: 1) set->tags[hctx_idx] = blk_mq_alloc_rq_map() 2) blk_mq_alloc_rqs(..., set->tags[hctx_idx]) into one step: set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs() Since tags is not initialized yet in this case, fix the problem by checking if tags is NULL pointer in blk_mq_clear_rq_mapping(). Fixes: 63064be150e4 ("blk-mq: Add blk_mq_alloc_map_and_rqs()") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20221011142253.4015966-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30block: allow end_io based requests in the completion batch handlingJens Axboe
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 <anuj20.g@samsung.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Co-developed-by: Stefan Roesch <shr@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30block: change request end_io handler to pass back a return valueJens Axboe
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 <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30block: enable batched allocation for blk_mq_alloc_request()Jens Axboe
The filesystem IO path can take advantage of allocating batches of requests, if the underlying submitter tells the block layer about it through the blk_plug. For passthrough IO, the exported API is the blk_mq_alloc_request() helper, and that one does not allow for request caching. Wire up request caching for blk_mq_alloc_request(), which is generally done without having a bio available upfront. Tested-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30Merge branch 'for-6.1/io_uring' into for-6.1/passthroughJens Axboe
* 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 ...
2022-09-30Merge branch 'for-6.1/block' into for-6.1/passthroughJens Axboe
* for-6.1/block: (162 commits) sbitmap: fix lockup while swapping block: add rationale for not using blk_mq_plug() when applicable block: adapt blk_mq_plug() to not plug for writes that require a zone lock s390/dasd: use blk_mq_alloc_disk blk-cgroup: don't update the blkg lookup hint in blkg_conf_prep nvmet: don't look at the request_queue in nvmet_bdev_set_limits nvmet: don't look at the request_queue in nvmet_bdev_zone_mgmt_emulate_all blk-mq: use quiesced elevator switch when reinitializing queues block: replace blk_queue_nowait with bdev_nowait nvme: remove nvme_ctrl_init_connect_q nvme-loop: use the tagset alloc/free helpers nvme-loop: store the generic nvme_ctrl in set->driver_data nvme-loop: initialize sqsize later nvme-fc: use the tagset alloc/free helpers nvme-fc: store the generic nvme_ctrl in set->driver_data nvme-fc: keep ctrl->sqsize in sync with opts->queue_size nvme-rdma: use the tagset alloc/free helpers nvme-rdma: store the generic nvme_ctrl in set->driver_data nvme-tcp: use the tagset alloc/free helpers nvme-tcp: store the generic nvme_ctrl in set->driver_data ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29block: add rationale for not using blk_mq_plug() when applicablePankaj Raghav
There are two places in the block layer at the moment where blk_mq_plug() helper could be used instead of directly accessing the plug from struct current. In both these cases, directly accessing the plug should not have any consequences for zoned devices. Make the intent explicit by adding comments instead of introducing unwanted checks with blk_mq_plug() helper.[1] [1] https://lore.kernel.org/linux-block/f6e54907-1035-2b2c-6387-ed178be05ccb@kernel.dk/ Signed-off-by: Pankaj Raghav <p.raghav@samsung.com> Suggested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20220929144141.140077-1-p.raghav@samsung.com [axboe: fixup multi-line comment style] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-mq: use quiesced elevator switch when reinitializing queuesKeith Busch
The hctx's run_work may be racing with the elevator switch when reinitializing hardware queues. The queue is merely frozen in this context, but that only prevents requests from allocating and doesn't stop the hctx work from running. The work may get an elevator pointer that's being torn down, and can result in use-after-free errors and kernel panics (example below). Use the quiesced elevator switch instead, and make the previous one static since it is now only used locally. nvme nvme0: resetting controller nvme nvme0: 32/0/0 default/read/poll queues BUG: kernel NULL pointer dereference, address: 0000000000000008 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 80000020c8861067 P4D 80000020c8861067 PUD 250f8c8067 PMD 0 Oops: 0000 [#1] SMP PTI Workqueue: kblockd blk_mq_run_work_fn RIP: 0010:kyber_has_work+0x29/0x70 ... Call Trace: __blk_mq_do_dispatch_sched+0x83/0x2b0 __blk_mq_sched_dispatch_requests+0x12e/0x170 blk_mq_sched_dispatch_requests+0x30/0x60 __blk_mq_run_hw_queue+0x2b/0x50 process_one_work+0x1ef/0x380 worker_thread+0x2d/0x3e0 Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220927155652.3260724-1-kbusch@fb.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-24blk-mq: don't redirect completion for hctx withs only one ctx mappingLiu Song
High-performance NVMe devices usually support a large hw queues, which ensures a 1:1 mapping of hctx and ctx. In this case there will be no remote request, so we don't need to care about it. Signed-off-by: Liu Song <liusong@linux.alibaba.com> Link: https://lore.kernel.org/r/1663731123-81536-1-git-send-email-liusong@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21block: export blk_rq_is_pollKanchan Joshi
This is in preparation to support iopoll for nvme passthrough. Signed-off-by: Kanchan Joshi <joshi.k@samsung.com> Link: https://lore.kernel.org/r/20220823161443.49436-4-joshi.k@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-05blk-mq: remove unneeded needs_restart checkMiaohe Lin
If code reaches here, needs_restart must be true. Remove this unneeded needs_restart check. No functional change intended. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Link: https://lore.kernel.org/r/20220905101950.4606-1-linmiaohe@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-22block: Change the return type of blk_mq_map_queues() into voidBart Van Assche
Since blk_mq_map_queues() and the .map_queues() callbacks always return 0, change their return type into void. Most callers ignore the returned value anyway. Cc: Christoph Hellwig <hch@lst.de> Cc: Jason Wang <jasowang@redhat.com> Cc: Keith Busch <kbusch@kernel.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: John Garry <john.garry@huawei.com> Acked-by: Md Haris Iqbal <haris.iqbal@ionos.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Link: https://lore.kernel.org/r/20220815170043.19489-3-bvanassche@acm.org [axboe: fold in fix from Bart] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-19blk-mq: fix io hung due to missing commit_rqsYu Kuai
Currently, in virtio_scsi, if 'bd->last' is not set to true while dispatching request, such io will stay in driver's queue, and driver will wait for block layer to dispatch more rqs. However, if block layer failed to dispatch more rq, it should trigger commit_rqs to inform driver. There is a problem in blk_mq_try_issue_list_directly() that commit_rqs won't be called: // assume that queue_depth is set to 1, list contains two rq blk_mq_try_issue_list_directly blk_mq_request_issue_directly // dispatch first rq // last is false __blk_mq_try_issue_directly blk_mq_get_dispatch_budget // succeed to get first budget __blk_mq_issue_directly scsi_queue_rq cmd->flags |= SCMD_LAST virtscsi_queuecommand kick = (sc->flags & SCMD_LAST) != 0 // kick is false, first rq won't issue to disk queued++ blk_mq_request_issue_directly // dispatch second rq __blk_mq_try_issue_directly blk_mq_get_dispatch_budget // failed to get second budget ret == BLK_STS_RESOURCE blk_mq_request_bypass_insert // errors is still 0 if (!list_empty(list) || errors && ...) // won't pass, commit_rqs won't be called In this situation, first rq relied on second rq to dispatch, while second rq relied on first rq to complete, thus they will both hung. Fix the problem by also treat 'BLK_STS_*RESOURCE' as 'errors' since it means that request is not queued successfully. Same problem exists in blk_mq_dispatch_rq_list(), 'BLK_STS_*RESOURCE' can't be treated as 'errors' here, fix the problem by calling commit_rqs if queue_rq return 'BLK_STS_*RESOURCE'. Fixes: d666ba98f849 ("blk-mq: add mq_ops->commit_rqs()") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220726122224.1790882-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-18blk-mq: run queue no matter whether the request is the last requestYufen Yu
We do test on a virtio scsi device (/dev/sda) and the default mq scheduler is 'none'. We found a IO hung as following: blk_finish_plug blk_mq_plug_issue_direct scsi_mq_get_budget //get budget_token fail and sdev->restarts=1 scsi_end_request scsi_run_queue_async //sdev->restart=0 and run queue blk_mq_request_bypass_insert //add request to hctx->dispatch list //continue to dispath plug list blk_mq_dispatch_plug_list blk_mq_try_issue_list_directly //success issue all requests from plug list After .get_budget fail, scsi_mq_get_budget will increase 'restarts'. Normally, it will run hw queue when io complete and set 'restarts' as 0. But if we run queue before adding request to the dispatch list and blk_mq_dispatch_plug_list also success issue all requests, then on one will run queue, and the request will be stall in the dispatch list and cannot complete forever. It is wrong to use last request of plug list to decide if run queue is needed since all the remained requests in plug list may be from other hctxs. To fix the bug, pass run_queue as true always to blk_mq_request_bypass_insert(). Fix-suggested-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Yufen Yu <yuyufen@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Fixes: dc5fc361d891 ("block: attempt direct issue of plug list") Link: https://lore.kernel.org/r/20220803023355.3687360-1-yuyufen@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-18blk-mq: remove unused function blk_mq_queue_stopped()Yu Kuai
blk_mq_queue_stopped() doesn't have any caller, which was found by code coverage test, thus remove it. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20220818063555.3741222-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: pass struct queue_limits to the bio splitting helpersChristoph Hellwig
Allow using the splitting helpers on just a queue_limits instead of a full request_queue structure. This will eventually allow file systems or remapping drivers to split REQ_OP_ZONE_APPEND bios based on limits calculated as the minimum common capabilities over multiple devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: change the blk_queue_bounce calling conventionChristoph Hellwig
The double indirect bio leads to somewhat suboptimal code generation. Instead return the (original or split) bio, and make sure the request_queue arguments to the lower level helpers is passed after the bio to avoid constant reshuffling of the argument passing registers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: change the blk_queue_split calling conventionChristoph Hellwig
The double indirect bio leads to somewhat suboptimal code generation. Instead return the (original or split) bio, and make sure the request_queue arguments to the lower level helpers is passed after the bio to avoid constant reshuffling of the argument passing registers. Also give it and the helpers used to implement it more descriptive names. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220727162300.3089193-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-21blk-mq: fix error handling in __blk_mq_alloc_diskChristoph Hellwig
To fully clean up the queue if the disk allocation fails we need to call blk_mq_destroy_queue and not just blk_put_queue. Fixes: 6f8191fdf41d ("block: simplify disk shutdown") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220720130541.1323531-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14block: Use the new blk_opf_t typeBart Van Assche
Use the new blk_opf_t type for arguments and variables that represent request flags or a bitwise combination of a request operation and request flags. Rename the function arguments and also a structure member that hold a request operation and flags from 'rw' into 'opf'. This patch does not change any functionality. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Damien Le Moal <damien.lemoal@wdc.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220714180729.1065367-7-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06block: simplify blk_mq_plugChristoph Hellwig
Drop the unused q argument, and invert the check to move the exception into a branch and the regular path as the normal return. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220706070350.1703384-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06blk-mq: Drop 'reserved' arg of busy_tag_iter_fnJohn Garry
We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter function so it may be dropped. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> #nvme Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/1657109034-206040-6-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06blk-mq: Drop blk_mq_ops.timeout 'reserved' argJohn Garry
With new API blk_mq_is_reserved_rq() we can tell if a request is from the reserved pool, so stop passing 'reserved' arg. There is actually only a single user of that arg for all the callback implementations, which can use blk_mq_is_reserved_rq() instead. This will also allow us to stop passing the same 'reserved' around the blk-mq iter functions next. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/1657109034-206040-4-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06blk-mq: Add a flag for reserved requestsJohn Garry
Add a flag for reserved requests so that drivers may know this for any special handling. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/1657109034-206040-3-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28blk-mq: rename blk_mq_sysfs_{,un}registerChristoph Hellwig
Add a _hctx postfix to better describe what the functions do, match the debugfs equivalents and release the old names for functions that should be using them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220628171850.1313069-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28block: simplify disk shutdownChristoph Hellwig
Set the queue dying flag and call blk_mq_exit_queue from del_gendisk for all disks that do not have separately allocated queues, and thus remove the need to call blk_cleanup_queue for them. Rename blk_cleanup_disk to blk_mq_destroy_queue to make it clear that this function is intended only for separately allocated blk-mq queues. This saves an extra queue freeze for devices without a separately allocated queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20220619060552.1850436-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27block: Always initialize bio IO priority on submitJan Kara
Currently, IO priority set in task's IO context is not reflected in the bio->bi_ioprio for most IO (only io_uring and direct IO set it). This results in odd results where process is submitting some bios with one priority and other bios with a different (unset) priority and due to differing priorities bios cannot be merged. Make sure bio->bi_ioprio is always set on bio submission. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220623074840.5960-9-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27block: Initialize bio priority earlierJan Kara
Bio's IO priority needs to be initialized before we try to merge the bio with other bios. Otherwise we could merge bios which would otherwise receive different IO priorities leading to possible QoS issues. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220623074840.5960-8-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27blk-ioprio: Convert from rqos policy to direct callJan Kara
Convert blk-ioprio handling from a rqos policy to a direct call from blk_mq_submit_bio(). Firstly, blk-ioprio is not much of a rqos policy anyway, it just needs a hook in bio submission path to set the bio's IO priority. Secondly, the rqos .track hook gets actually called too late for blk-ioprio purposes and introducing a special rqos hook just for blk-ioprio looks even weirder. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220623074840.5960-7-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27blk-mq: Don't disable preemption around __blk_mq_run_hw_queue().Sebastian Andrzej Siewior
__blk_mq_delay_run_hw_queue() disables preemption to get a stable current CPU number and then invokes __blk_mq_run_hw_queue() if the CPU number is part the mask. __blk_mq_run_hw_queue() acquires a spin_lock_t which is a sleeping lock on PREEMPT_RT and can't be acquired with disabled preemption. It is not required for correctness to invoke __blk_mq_run_hw_queue() on a CPU matching hctx->cpumask. Both (async and direct requests) can run on a CPU not matching hctx->cpumask. The CPU mask without disabling preemption and invoking __blk_mq_run_hw_queue(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/YrLSEiNvagKJaDs5@linutronix.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27block: Make blk_mq_get_sq_hctx() select the proper hardware queue typeBart Van Assche
Since the introduction of blk_mq_get_hctx_type() the operation type in the second argument of blk_mq_get_hctx_type() matters. The introduction of blk_mq_get_hctx_type() caused blk_mq_get_sq_hctx() to select a hardware queue of type HCTX_TYPE_READ instead of HCTX_TYPE_DEFAULT. Switch to hardware queue type HCTX_TYPE_DEFAULT since HCTX_TYPE_READ should only be used for read requests. Cc: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220615225549.1054905-4-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-21block: pop cached rq before potentially blocking rq_qos_throttle()Jens Axboe
If rq_qos_throttle() ends up blocking, then we will have invalidated and flushed our current plug. Since blk_mq_get_cached_request() hasn't popped the cached request off the plug list just yet, we end holding a pointer to a request that is no longer valid. This insta-crashes with rq->mq_hctx being NULL in the validity checks just after. Pop the request off the cached list before doing rq_qos_throttle() to avoid using a potentially stale request. Fixes: 0a5aa8d161d1 ("block: fix blk_mq_attempt_bio_merge and rq_qos_throttle protection") Reported-by: Dylan Yudaken <dylany@fb.com> Tested-by: Dylan Yudaken <dylany@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-16blk-mq: don't clear flush_rq from tags->rqs[]Ming Lei
commit 364b61818f65 ("blk-mq: clearing flush request reference in tags->rqs[]") is added to clear the to-be-free flush request from tags->rqs[] for avoiding use-after-free on the flush rq. Yu Kuai reported that blk_mq_clear_flush_rq_mapping() slows down boot time by ~8s because running scsi probe which may create and remove lots of unpresent LUNs on megaraid-sas which uses BLK_MQ_F_TAG_HCTX_SHARED and each request queue has lots of hw queues. Improve the situation by not running blk_mq_clear_flush_rq_mapping if disk isn't added when there can't be any flush request issued. Reviewed-by: Christoph Hellwig <hch@lst.de> Reported-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220616014401.817001-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-16blk-mq: avoid to touch q->elevator without any protectionMing Lei
q->elevator is referred in blk_mq_has_sqsched() without any protection, no .q_usage_counter is held, no queue srcu and rcu read lock is held, so potential use-after-free may be triggered. Fix the issue by adding one queue flag for checking if the elevator uses single queue style dispatch. Meantime the elevator feature flag of ELEVATOR_F_MQ_AWARE isn't needed any more. Cc: Jan Kara <jack@suse.cz> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220616014401.817001-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-16blk-mq: protect q->elevator by ->sysfs_lock in blk_mq_elv_switch_noneMing Lei
elevator can be tore down by sysfs switch interface or disk release, so hold ->sysfs_lock before referring to q->elevator, then potential use-after-free can be avoided. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220616014401.817001-2-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-16block: Fix handling of offline queues in blk_mq_alloc_request_hctx()Bart Van Assche
This patch prevents that test nvme/004 triggers the following: UBSAN: array-index-out-of-bounds in block/blk-mq.h:135:9 index 512 is out of range for type 'long unsigned int [512]' Call Trace: show_stack+0x52/0x58 dump_stack_lvl+0x49/0x5e dump_stack+0x10/0x12 ubsan_epilogue+0x9/0x3b __ubsan_handle_out_of_bounds.cold+0x44/0x49 blk_mq_alloc_request_hctx+0x304/0x310 __nvme_submit_sync_cmd+0x70/0x200 [nvme_core] nvmf_connect_io_queue+0x23e/0x2a0 [nvme_fabrics] nvme_loop_connect_io_queues+0x8d/0xb0 [nvme_loop] nvme_loop_create_ctrl+0x58e/0x7d0 [nvme_loop] nvmf_create_ctrl+0x1d7/0x4d0 [nvme_fabrics] nvmf_dev_write+0xae/0x111 [nvme_fabrics] vfs_write+0x144/0x560 ksys_write+0xb7/0x140 __x64_sys_write+0x42/0x50 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Fixes: 20e4d8139319 ("blk-mq: simplify queue mapping & schedule with each possisble CPU") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220615210004.1031820-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-03Merge tag 'for-5.19/block-exec-2022-06-02' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block request execute cleanups from Jens Axboe: "This change was advertised in the initial core block pull request, but didn't actually make that branch as we deferred it to a post-merge pull request to avoid a bunch of cross branch issues. This series cleans up the block execute path quite nicely" * tag 'for-5.19/block-exec-2022-06-02' of git://git.kernel.dk/linux-block: blk-mq: remove the done argument to blk_execute_rq_nowait blk-mq: avoid a mess of casts for blk_end_sync_rq blk-mq: remove __blk_execute_rq_nowait
2022-06-03Merge tag 'for-5.19/block-2022-06-02' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Just a collection of fixes that have been queued up since the initial merge window pull request, the majority of which are targeted for stable as well. One bio_set fix that fixes an issue with the dm adoption of cached bio structs that got introduced in this merge window" * tag 'for-5.19/block-2022-06-02' of git://git.kernel.dk/linux-block: block: Fix potential deadlock in blk_ia_range_sysfs_show() block: fix bio_clone_blkg_association() to associate with proper blkcg_gq block: remove useless BUG_ON() in blk_mq_put_tag() blk-mq: do not update io_ticks with passthrough requests block: make bioset_exit() fully resilient against being called twice block: use bio_queue_enter instead of blk_queue_enter in bio_poll block: document BLK_STS_AGAIN usage block: take destination bvec offsets into account in bio_copy_data_iter blk-iolatency: Fix inflight count imbalances and IO hangs on offline blk-mq: don't touch ->tagset in blk_mq_get_sq_hctx
2022-05-30blk-mq: do not update io_ticks with passthrough requestsHaisu Wang
Flush or passthrough requests are not accounted as normal IO in completion. To reflect iostat for slow IO, io_ticks is updated when stat show called based on inflight numbers. It may cause inconsistent io_ticks calculation result. So do not account non-passthrough request when check inflight. Fixes: 86d7331299fd ("block: update io_ticks when io hang") Signed-off-by: Haisu Wang <haisuwang@tencent.com> Reviewed-by: samuelliao <samuelliao@tencent.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220530064059.1120058-1-haisuwang@tencent.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-28blk-mq: remove the done argument to blk_execute_rq_nowaitChristoph Hellwig
Let the caller set it together with the end_io_data instead of passing a pointless argument. Note the the target code did in fact already set it and then just overrode it again by calling blk_execute_rq_nowait. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Kanchan Joshi <joshi.k@samsung.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220524121530.943123-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-28blk-mq: avoid a mess of casts for blk_end_sync_rqChristoph Hellwig
Instead of trying to cast a __bitwise 32-bit integer to a larger integer and then a pointer, just allow a struct with the blk_status_t and the completion on stack and set the end_io_data to that. Use the opportunity to move the code to where it belongs and drop rather confusing comments. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220524121530.943123-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-28blk-mq: remove __blk_execute_rq_nowaitChristoph Hellwig
We don't want to plug for synchronous execution that where we immediately wait for the request. Once that is done not a whole lot of code is shared, so just remove __blk_execute_rq_nowait. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220524121530.943123-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-23Merge tag 'for-5.19/block-2022-05-22' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: "Here are the core block changes for 5.19. This contains: - blk-throttle accounting fix (Laibin) - Series removing redundant assignments (Michal) - Expose bio cache via the bio_set, so that DM can use it (Mike) - Finish off the bio allocation interface cleanups by dealing with the weirdest member of the family. bio_kmalloc combines a kmalloc for the bio and bio_vecs with a hidden bio_init call and magic cleanup semantics (Christoph) - Clean up the block layer API so that APIs consumed by file systems are (almost) only struct block_device based, so that file systems don't have to poke into block layer internals like the request_queue (Christoph) - Clean up the blk_execute_rq* API (Christoph) - Clean up various lose end in the blk-cgroup code to make it easier to follow in preparation of reworking the blkcg assignment for bios (Christoph) - Fix use-after-free issues in BFQ when processes with merged queues get moved to different cgroups (Jan) - BFQ fixes (Jan) - Various fixes and cleanups (Bart, Chengming, Fanjun, Julia, Ming, Wolfgang, me)" * tag 'for-5.19/block-2022-05-22' of git://git.kernel.dk/linux-block: (83 commits) blk-mq: fix typo in comment bfq: Remove bfq_requeue_request_body() bfq: Remove superfluous conversion from RQ_BIC() bfq: Allow current waker to defend against a tentative one bfq: Relax waker detection for shared queues blk-cgroup: delete rcu_read_lock_held() WARN_ON_ONCE() blk-throttle: Set BIO_THROTTLED when bio has been throttled blk-cgroup: Remove unnecessary rcu_read_lock/unlock() blk-cgroup: always terminate io.stat lines block, bfq: make bfq_has_work() more accurate block, bfq: protect 'bfqd->queued' by 'bfqd->lock' block: cleanup the VM accounting in submit_bio block: Fix the bio.bi_opf comment block: reorder the REQ_ flags blk-iocost: combine local_stat and desc_stat to stat block: improve the error message from bio_check_eod block: allow passing a NULL bdev to bio_alloc_clone/bio_init_clone block: remove superfluous calls to blkcg_bio_issue_init kthread: unexport kthread_blkcg blk-cgroup: cleanup blkcg_maybe_throttle_current ...
2022-05-23blk-mq: don't touch ->tagset in blk_mq_get_sq_hctxMing Lei
blk_mq_run_hw_queues() could be run when there isn't queued request and after queue is cleaned up, at that time tagset is freed, because tagset lifetime is covered by driver, and often freed after blk_cleanup_queue() returns. So don't touch ->tagset for figuring out current default hctx by the mapping built in request queue, so use-after-free on tagset can be avoided. Meantime this way should be fast than retrieving mapping from tagset. Cc: "yukuai (C)" <yukuai3@huawei.com> Cc: Jan Kara <jack@suse.cz> Fixes: b6e68ee82585 ("blk-mq: Improve performance of non-mq IO schedulers with multiple HW queues") Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220522122350.743103-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-21blk-mq: fix typo in commentJulia Lawall
Spelling mistake (triple letters) in comment. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/20220521111145.81697-29-Julia.Lawall@inria.fr Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-12blk-mq: fix passthrough pluggingMing Lei
First we can't add request into plug list in blk_mq_request_bypass_insert which may be called when flushing plug list, so nested plug is caused. Second if polled passthrough request is inserted via blk_execute_rq(), it can't be added to plug list too since io polling needs the request to be issued to driver. Fixes the two by moving plugging into blk_execute_rq_no_wait(). Cc: Christoph Hellwig <hch@lst.de> Fixes: 1c2d2fff6dc0 ("block: wire-up support for passthrough plugging") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220512140010.1458645-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>