linux/block
Damien Le Moal 737eb78e82 block: Delay default elevator initialization
When elevator_init_mq() is called from blk_mq_init_allocated_queue(),
the only information known about the device is the number of hardware
queues as the block device scan by the device driver is not completed
yet for most drivers. The device type and elevator required features
are not set yet, preventing to correctly select the default elevator
most suitable for the device.

This currently affects all multi-queue zoned block devices which default
to the "none" elevator instead of the required "mq-deadline" elevator.
These drives currently include host-managed SMR disks connected to a
smartpqi HBA and null_blk block devices with zoned mode enabled.
Upcoming NVMe Zoned Namespace devices will also be affected.

Fix this by adding the boolean elevator_init argument to
blk_mq_init_allocated_queue() to control the execution of
elevator_init_mq(). Two cases exist:
1) elevator_init = false is used for calls to
   blk_mq_init_allocated_queue() within blk_mq_init_queue(). In this
   case, a call to elevator_init_mq() is added to __device_add_disk(),
   resulting in the delayed initialization of the queue elevator
   after the device driver finished probing the device information. This
   effectively allows elevator_init_mq() access to more information
   about the device.
2) elevator_init = true preserves the current behavior of initializing
   the elevator directly from blk_mq_init_allocated_queue(). This case
   is used for the special request based DM devices where the device
   gendisk is created before the queue initialization and device
   information (e.g. queue limits) is already known when the queue
   initialization is executed.

Additionally, to make sure that the elevator initialization is never
done while requests are in-flight (there should be none when the device
driver calls device_add_disk()), freeze and quiesce the device request
queue before calling blk_mq_init_sched() in elevator_init_mq().

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-05 19:52:34 -06:00
..
partitions docs: admin-guide: add a series of orphaned documents 2019-07-15 11:03:02 -03:00
badblocks.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
bfq-cgroup.c blkcg: pass @q and @blkcg into blkcg_pol_alloc_pd_fn() 2019-08-28 21:17:01 -06:00
bfq-iosched.c for-linus-20190726 2019-07-26 10:32:12 -07:00
bfq-iosched.h block, bfq: detect wakers and unconditionally inject their I/O 2019-06-25 09:07:34 -06:00
bfq-wf2q.c block: switch all files cleared marked as GPLv2 or later to SPDX tags 2019-04-30 16:11:59 -06:00
bio-integrity.c block/bio-integrity: fix a memory leak bug 2019-07-11 20:01:21 -06:00
bio.c block: move same page handling from __bio_add_pc_page to the callers 2019-08-22 07:14:39 -06:00
blk-cgroup.c blkcg: separate blkcg_conf_get_disk() out of blkg_conf_prep() 2019-08-28 21:17:04 -06:00
blk-core.c block/rq_qos: add rq_qos_merge() 2019-08-28 21:17:05 -06:00
blk-exec.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-flush.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
blk-integrity.c docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
blk-ioc.c block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-iocost.c blkcg: add missing NULL check in ioc_cpd_alloc() 2019-08-30 07:16:19 -06:00
blk-iolatency.c blkcg: s/RQ_QOS_CGROUP/RQ_QOS_LATENCY/ 2019-08-28 21:17:08 -06:00
blk-lib.c block: fix 32 bit overflow in __blkdev_issue_discard() 2018-11-14 08:17:18 -07:00
blk-map.c block: remove the bi_phys_segments field in struct bio 2019-06-20 10:29:22 -06:00
blk-merge.c block: Improve physical block alignment of split bios 2019-08-04 21:41:29 -06:00
blk-mq-cpumap.c blk-mq: balance mapping between present CPUs and queues 2019-08-04 21:43:12 -06:00
blk-mq-debugfs-zoned.c block: Cleanup license notice 2019-01-17 21:21:40 -07:00
blk-mq-debugfs.c for-5.3/block-20190708 2019-07-09 10:45:06 -07:00
blk-mq-debugfs.h blk-mq: no need to check return value of debugfs_create functions 2019-06-13 03:00:30 -06:00
blk-mq-pci.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-rdma.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-sched.c blk-mq: remove blk_mq_put_ctx() 2019-07-02 21:03:27 -06:00
blk-mq-sched.h block: blk-mq: Remove blk_mq_sched_started_request and started_request 2019-07-23 07:25:09 -06:00
blk-mq-sysfs.c block: split .sysfs_lock into two locks 2019-08-27 10:40:20 -06:00
blk-mq-tag.c blk-mq: introduce blk_mq_tagset_wait_completed_request() 2019-08-04 21:41:29 -06:00
blk-mq-tag.h Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
blk-mq-virtio.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq.c block: Delay default elevator initialization 2019-09-05 19:52:34 -06:00
blk-mq.h block: Disable write plugging for zoned block devices 2019-07-10 14:18:01 -06:00
blk-pm.c block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-pm.h block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-rq-qos.c block/rq_qos: implement rq_qos_ops->queue_depth_changed() 2019-08-28 21:17:07 -06:00
blk-rq-qos.h blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
blk-settings.c block: Introduce elevator features 2019-09-05 19:52:33 -06:00
blk-softirq.c block: remove a few unused exports 2018-11-15 12:13:25 -07:00
blk-stat.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-stat.h block: deactivate blk_stat timer in wbt_disable_default() 2018-12-12 06:47:51 -07:00
blk-sysfs.c block: split .sysfs_lock into two locks 2019-08-27 10:40:20 -06:00
blk-throttle.c blkcg: pass @q and @blkcg into blkcg_pol_alloc_pd_fn() 2019-08-28 21:17:01 -06:00
blk-timeout.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-wbt.c block/rq_qos: implement rq_qos_ops->queue_depth_changed() 2019-08-28 21:17:07 -06:00
blk-wbt.h block/rq_qos: implement rq_qos_ops->queue_depth_changed() 2019-08-28 21:17:07 -06:00
blk-zoned.c blk-zoned: implement REQ_OP_ZONE_RESET_ALL 2019-08-04 21:41:29 -06:00
blk.h block: Change elevator_init_mq() to always succeed 2019-09-05 19:52:33 -06:00
bounce.c block: remove the i argument to bio_for_each_segment_all 2019-04-30 09:26:13 -06:00
bsg-lib.c block: Fix bsg_setup_queue() kernel-doc header 2019-05-31 15:12:34 -06:00
bsg.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
cmdline-parser.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compat_ioctl.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
elevator.c block: Delay default elevator initialization 2019-09-05 19:52:34 -06:00
genhd.c block: Delay default elevator initialization 2019-09-05 19:52:34 -06:00
ioctl.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
ioprio.c docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
Kconfig blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
Kconfig.iosched docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
kyber-iosched.c blk-mq: remove blk_mq_put_ctx() 2019-07-02 21:03:27 -06:00
Makefile blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
mq-deadline.c block: Introduce elevator features 2019-09-05 19:52:33 -06:00
opal_proto.h block: sed-opal: Removed duplicate OPAL_METHOD_LENGTH definition 2019-08-20 09:34:49 -06:00
partition-generic.c block: fix use-after-free on gendisk 2019-04-22 09:48:12 -06:00
scsi_ioctl.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
sed-opal.c block: sed-opal: Remove always false conditional statement 2019-08-20 09:33:21 -06:00
t10-pi.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00