linux-toradex.git/block/blk-mq-sysfs.c, branch v5.3-rc1

Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block

2019-05-08T01:14:36+00:00

Pull block updates from Jens Axboe:
 "Nothing major in this series, just fixes and improvements all over the
  map. This contains:

   - Series of fixes for sed-opal (David, Jonas)

   - Fixes and performance tweaks for BFQ (via Paolo)

   - Set of fixes for bcache (via Coly)

   - Set of fixes for md (via Song)

   - Enabling multi-page for passthrough requests (Ming)

   - Queue release fix series (Ming)

   - Device notification improvements (Martin)

   - Propagate underlying device rotational status in loop (Holger)

   - Removal of mtip32xx trim support, which has been disabled for years
     (Christoph)

   - Improvement and cleanup of nvme command handling (Christoph)

   - Add block SPDX tags (Christoph)

   - Cleanup/hardening of bio/bvec iteration (Christoph)

   - A few NVMe pull requests (Christoph)

   - Removal of CONFIG_LBDAF (Christoph)

   - Various little fixes here and there"

* tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits)
  block: fix mismerge in bvec_advance
  block: don't drain in-progress dispatch in blk_cleanup_queue()
  blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release
  blk-mq: always free hctx after request queue is freed
  blk-mq: split blk_mq_alloc_and_init_hctx into two parts
  blk-mq: free hw queue's resource in hctx's release handler
  blk-mq: move cancel of requeue_work into blk_mq_release
  blk-mq: grab .q_usage_counter when queuing request from plug code path
  block: fix function name in comment
  nvmet: protect discovery change log event list iteration
  nvme: mark nvme_core_init and nvme_core_exit static
  nvme: move command size checks to the core
  nvme-fabrics: check more command sizes
  nvme-pci: check more command sizes
  nvme-pci: remove an unneeded variable initialization
  nvme-pci: unquiesce admin queue on shutdown
  nvme-pci: shutdown on timeout during deletion
  nvme-pci: fix psdt field for single segment sgls
  nvme-multipath: don't print ANA group state by default
  nvme-multipath: split bios with the ns_head bio_set before submitting
  ...

blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release

2019-05-04T13:24:09+00:00

hctx is always released after requeue is freed.

With holding queue's kobject refcount, it is safe for driver to run queue,
so one run queue might be scheduled after blk_sync_queue() is done.

So moving the cancel of hctx->run_work into blk_mq_hw_sysfs_release()
for avoiding run released queue.

Cc: Dongli Zhang 
Cc: James Smart 
Cc: Bart Van Assche 
Cc: linux-scsi@vger.kernel.org,
Cc: Martin K . Petersen ,
Cc: Christoph Hellwig ,
Cc: James E . J . Bottomley ,
Reviewed-by: Bart Van Assche 
Reviewed-by: Hannes Reinecke 
Tested-by: James Smart 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe

blk-mq: free hw queue's resource in hctx's release handler

2019-05-04T13:24:05+00:00

Once blk_cleanup_queue() returns, tags shouldn't be used any more,
because blk_mq_free_tag_set() may be called. Commit 45a9c9d909b2
("blk-mq: Fix a use-after-free") fixes this issue exactly.

However, that commit introduces another issue. Before 45a9c9d909b2,
we are allowed to run queue during cleaning up queue if the queue's
kobj refcount is held. After that commit, queue can't be run during
queue cleaning up, otherwise oops can be triggered easily because
some fields of hctx are freed by blk_mq_free_queue() in blk_cleanup_queue().

We have invented ways for addressing this kind of issue before, such as:

	8dc765d438f1 ("SCSI: fix queue cleanup race before queue initialization is done")
	c2856ae2f315 ("blk-mq: quiesce queue before freeing queue")

But still can't cover all cases, recently James reports another such
kind of issue:

	https://marc.info/?l=linux-scsi&m=155389088124782&w=2

This issue can be quite hard to address by previous way, given
scsi_run_queue() may run requeues for other LUNs.

Fixes the above issue by freeing hctx's resources in its release handler, and this
way is safe becasue tags isn't needed for freeing such hctx resource.

This approach follows typical design pattern wrt. kobject's release handler.

Cc: Dongli Zhang 
Cc: James Smart 
Cc: Bart Van Assche 
Cc: linux-scsi@vger.kernel.org,
Cc: Martin K . Petersen ,
Cc: Christoph Hellwig ,
Cc: James E . J . Bottomley ,
Reported-by: James Smart 
Fixes: 45a9c9d909b2 ("blk-mq: Fix a use-after-free")
Cc: stable@vger.kernel.org
Reviewed-by: Hannes Reinecke 
Reviewed-by: Christoph Hellwig 
Tested-by: James Smart 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe

block: add SPDX tags to block layer files missing licensing information

2019-04-30T22:12:03+00:00

Various block layer files do not have any licensing information at all.
Add SPDX tags for the default kernel GPLv2 license to those.

Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

block: Replace all ktype default_attrs with groups

2019-04-25T20:06:11+00:00

The kobj_type default_attrs field is being replaced by the
default_groups field. Replace all of the ktype default_attrs fields in
the block subsystem with default_groups and use the ATTRIBUTE_GROUPS
macro to create the default groups.

Remove default_ctx_attrs[] because it doesn't contain any attributes.

This patch was tested by verifying that the sysfs files for the
attributes in the default groups were created.

Signed-off-by: Kimberly Brown 
Reviewed-by: Bart Van Assche 
Signed-off-by: Greg Kroah-Hartman

blk-mq: export hctx->type in debugfs instead of sysfs

2018-12-17T12:44:45+00:00

Now we only export hctx->type via sysfs, and there isn't such info
in hctx entry under debugfs. We often use debugfs only to diagnose
queue mapping issue, so add the support in debugfs.

Queue mapping becomes a bit more complicated after multiple queue
mapping is supported, we may write blktest to verify if queue mapping
is valid based on blk-mq-debugfs.

Given not necessary to export hctx->type twice, so remove the export
from sysfs.

Cc: Jeff Moyer 
Cc: Mike Snitzer 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe

block: move queues types to the block layer

2018-12-04T18:38:17+00:00

Having another indirect all in the fast path doesn't really help
in our post-spectre world.  Also having too many queue type is just
going to create confusion, so I'd rather manage them centrally.

Note that the queue type naming and ordering changes a bit - the
first index now is the default queue for everything not explicitly
marked, the optional ones are read and poll queues.

Reviewed-by: Sagi Grimberg 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

blk-mq: not embed .mq_kobj and ctx->kobj into queue instance

2018-11-21T12:57:56+00:00

Even though .mq_kobj, ctx->kobj and q->kobj share same lifetime
from block layer's view, actually they don't because userspace may
grab one kobject anytime via sysfs.

This patch fixes the issue by the following approach:

1) introduce 'struct blk_mq_ctxs' for holding .mq_kobj and managing
all ctxs

2) free all allocated ctxs and the 'blk_mq_ctxs' instance in release
handler of .mq_kobj

3) grab one ref of .mq_kobj before initializing each ctx->kobj, so that
.mq_kobj is always released after all ctxs are freed.

This patch fixes kernel panic issue during booting when DEBUG_KOBJECT_RELEASE
is enabled.

Reported-by: Guenter Roeck 
Cc: "jianchao.wang" 
Tested-by: Guenter Roeck 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe

block: remove a few unused exports

2018-11-15T19:13:25+00:00

Reviewed-by: Hannes Reinecke 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

blk-mq: add 'type' attribute to the sysfs hctx directory

2018-11-07T20:44:59+00:00

It can be useful for a user to verify what type a given hardware
queue is, expose this information in sysfs.

Reviewed-by: Hannes Reinecke 
Reviewed-by: Bart Van Assche 
Reviewed-by: Keith Busch 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe