Commit Graph

47 Commits

Author SHA1 Message Date
Christoph Hellwig 5e62d5c993 nvmet: better data length validation
Currently the NVMe target stores the expexted data length in req->data_len
and uses that for data transfer decisions, but that does not take the
actual transfer length in the SGLs into account.  So this adds a new
transfer_len field, into which the transport drivers store the actual
transfer length.  We then check the two match before actually executing
the command.

The FC transport driver already had such a field, which is removed in
favour of the common one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Keith Busch ad22c355b7 nvme: remove handling of multiple AEN requests
The driver can handle tracking only one AEN request, so this patch
removes handling for multiple ones.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart  <james.smart@broadcom.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Keith Busch 38dabe210f nvme: centralize AEN defines
All the transports were unnecessarilly duplicating the AEN request
accounting. This patch defines everything in one place.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Guan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Christoph Hellwig 6cd53d14aa nvme: consolidate common code from ->reset_work
No change in behavior except that the FC code cancels two work items a
little later now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-11-01 16:28:06 +01:00
Christoph Hellwig c5017e8570 nvme: move controller deletion to common code
Move the ->delete_work and the associated helpers to common code instead
of duplicating them in every driver.  This also adds the missing reference
get/put for the loop driver.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-11-01 16:28:04 +01:00
Christoph Hellwig d22524a478 nvme: switch controller refcounting to use struct device
Instead of allocating a separate struct device for the character device
handle embedd it into struct nvme_ctrl and use it for the main controller
refcounting.  This removes double refcounting and gets us an automatic
reference for the character device operations.  We keep ctrl->device as a
pointer for now to avoid chaning printks all over, but in the future we
could look into message printing helpers that take a controller structure
similar to what other subsystems do.

Note the delete_ctrl operation always already has a reference (either
through sysfs due this change, or because every open file on the
/dev/nvme-fabrics node has a refernece) when it is entered now, so we
don't need to do the unless_zero variant there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
2017-10-27 09:04:07 +03:00
Israel Rukshin 86f36b9c6c nvme-loop: Add BLK_MQ_F_NO_SCHED flag to admin tag set
This flag is useful for admin queues that aren't used for normal IO.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-19 10:58:54 +02:00
Sagi Grimberg 34b6c2315e nvme: Add admin_tagset pointer to nvme_ctrl
Will be used when we centralize control flows.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:24 +02:00
Sagi Grimberg d09f2b45f3 nvme: split nvme_uninit_ctrl into stop and uninit
Usually before we teardown the controller we want to:
1. complete/cancel any ctrl inflight works
2. remove ctrl namespaces (only for removal though, resets
   shouldn't remove any namespaces).

but we do not want to destroy the controller device as
we might use it for logging during the teardown stage.

This patch adds nvme_start_ctrl() which queues inflight
controller works (aen, ns scan, queue start and keep-alive
if kato is set) and nvme_stop_ctrl() which cancels the works
namespace removal is left to the callers to handle.

Move nvme_uninit_ctrl after we are done with the
controller device.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-07-06 09:49:42 +03:00
Sagi Grimberg c1c0ffff3a nvme-loop: quiesce/unquiesce admin_q instead of start/stop its hw queues
unlike blk_mq_stop_hw_queues and blk_mq_start_stopped_hw_queues
quiescing/unquiescing respects the submission path rcu grace.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-07-06 09:48:43 +03:00
Sagi Grimberg 4368c39bf6 nvme-loop: update tagset nr_hw_queues after reconnecting/resetting
We might have more/less queues once we reconnect/reset. For
example due to cpu going online/offline

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-07-04 09:44:16 +03:00
Sagi Grimberg 20d0dfe65a nvme: move ctrl cap to struct nvme_ctrl
All transports use either a private cache of controller cap or an on-stack
copy, move it to the generic struct nvme_ctrl. In the future it will also
be maintained by the core.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-07-02 15:03:22 +03:00
Sagi Grimberg d858e5f04e nvme: move queue_count to the nvme_ctrl
All all transports use the queue_count in exactly the same, so move it to
the generic struct nvme_ctrl. In the future it will also be maintained by
the core.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-By: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-07-02 14:59:04 +03:00
Christoph Hellwig 180de00700 nvme: read the subsystem NQN from Identify Controller
NVMe 1.2.1 or later requires controllers to provide a subsystem NQN in the
Identify controller data structures.  Use this NQN for the subsysnqn
sysfs attribute by storing it in the nvme_ctrl structure after verifying
it.  For older controllers we generate a "fake" NQN per non-normative
text in the NVMe 1.3 spec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-28 08:14:13 -06:00
Sagi Grimberg 7aa1f42752 nvme: use a single NVME_AQ_DEPTH and relax it to 32
No need to differentiate fabrics from pci/loop, also lower
it to 32 as we don't really need 256 inflight admin commands.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-28 08:14:13 -06:00
Christoph Hellwig d86c4d8ef3 nvme: move reset workqueue handling to common code
This moves the nvme_reset function from the PCIe driver to common code,
renaming it to nvme_reset_ctrl in the process.  Additionally a new
helper nvme_reset_ctrl_sync is added for the case where we want to
wait for the reset.  To facilitate that the reset_work work structure is
move to the common nvme_ctrl structure and the ->reset_ctrl method is
removed.  For now the drivers initialize the reset_work with their own
callback, but longer term we should move to callouts for specific
parts of the reset process and move even more code to the core.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2017-06-15 15:48:34 +02:00
Christoph Hellwig 62b83b1834 nvme-loop: merge init_request methods
Now that we get the tagset passed we can have a single implementation for
the I/O and admin queues.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-15 14:30:33 +02:00
Sagi Grimberg 9a6327d2f2 nvme: Move transports to use nvme-core workqueue
Instead of each transport using it's own workqueue, export
a single nvme-core workqueue and use that instead.

In the future, this will help us moving towards some unification
if controller setup/teardown flows.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-15 14:29:43 +02:00
Sagi Grimberg a29001c53a nvme-loop: get rid of unused controller lock
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-15 14:28:14 +02:00
Christoph Hellwig fc17b6534e blk-mq: switch ->queue_rq return value to blk_status_t
Use the same values for use for request completion errors as the return
value from ->queue_rq.  BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Christoph Hellwig d3d5b87ddd nvme: replace is_flags field in nvme_ctrl_ops with a flags field
So that we can have more flags for transport-specific behavior.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2017-05-26 09:54:16 +03:00
Christoph Hellwig d6296d39e9 blk-mq: update ->init_request and ->exit_request prototypes
Remove the request_idx parameter, which can't be used safely now that we
support I/O schedulers with blk-mq.  Except for a superflous check in
mtip32xx it was unused anyway.

Also pass the tag_set instead of just the driver data - this allows drivers
to avoid some code duplication in a follow on cleanup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02 07:52:08 -06:00
Linus Torvalds 694752922b Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..
2017-05-01 10:39:57 -07:00
Christoph Hellwig 27fa9bc545 nvme: split nvme status from block req->errors
We want our own clearly defined error field for NVMe passthrough commands,
and the request errors field is going away in its current form.

Just store the status and result field in the nvme_request field from
hardirq completion context (using a new helper) and then generate a
Linux errno for the block layer only when we actually need it.

Because we can't overload the status value with a negative error code
for cancelled command we now have a flags filed in struct nvme_request
that contains a bit for this condition.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00
Sagi Grimberg 096e9e912b nvme-loop: Fix sqsize wrong assignment based on ctrl MQES capability
both our sqsize and the controller MQES cap are a 0 based value,
so making it 1 based is wrong.

Reported-by: Trapp, Darren <Darren.Trapp@cavium.com>
Reported-by: Daniel Verkamp <daniel.verkamp@intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-09 13:58:07 -06:00
Christoph Hellwig 77f02a7acd nvme: factor request completion code into a common helper
This avoids duplicating the logic four times, and it also allows to keep
some helpers static in core.c or just opencode them.

Note that this loses printing the aborted status on completions in the
PCI driver as that uses a data structure not available any more.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 7d9a5e7176 nvme-loop: increment request retries counter before requeuing
This way our max retry limit holds as well.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 3b06837630 nvme-loop: retrieve iod from the cqe command_id
useful to validate that the we didn't mess up
the command_id.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg d89a39be5f nvme-loop: remove unneeded includes
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg d19eef029d nvme-loop: fix module_init (theoretical) error path
if nvmf_register_transport happend to fail, we
need to nvmet_unregister_transport as well.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 297186d640 nvme-loop: remove some code duplication
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 6ecda70ea9 nvme-loop: handle cpu unplug when re-establishing the controller
If a cpu unplug event has occured, we need to take the minimum
of the provided nr_io_queues and the number of online cpus,
otherwise we won't be able to connect them as blk-mq mapping
won't dispatch to those queues.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04 09:44:43 -06:00
Sagi Grimberg d476983ea0 nvme-loop: fix a possible use-after-free when destroying the admin queue
we need to destroy the nvmet sq and let it finish gracefully
before continue to cleanup the queue.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04 09:44:41 -06:00
Eric Biggers f363b089be blk-mq: constify struct blk_mq_ops
Constify all instances of blk_mq_ops, as they are never modified.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-31 08:28:58 -06:00
Sagi Grimberg 945dd5bacc nvme-loop: handle cpu unplug when re-establishing the controller
If a cpu unplug event has occured, we need to take the minimum
of the provided nr_io_queues and the number of online cpus,
otherwise we won't be able to connect them as blk-mq mapping
won't dispatch to those queues.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-03-21 18:38:46 +02:00
Sagi Grimberg e4c5d3762e nvme-loop: fix a possible use-after-free when destroying the admin queue
we need to destroy the nvmet sq and let it finish gracefully
before continue to cleanup the queue.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-03-16 18:41:17 +02:00
Johannes Thumshirn e5a39dd823 nvme: make nvmf_register_transport require a create_ctrl callback
nvmf_create_ctrl() relys on the presence of a create_crtl callback in the
registered nvmf_transport_ops, so make nvmf_register_transport require one.

Update the available call-sites as well to reflect these changes.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-22 13:34:00 -07:00
Christoph Hellwig 57292b58dd block: introduce blk_rq_is_passthrough
This can be used to check for fs vs non-fs requests and basically
removes all knowledge of BLOCK_PC specific from the block layer,
as well as preparing for removing the cmd_type field in struct request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31 14:00:34 -07:00
Christoph Hellwig f9d03f96b9 block: improve handling of the magic discard payload
Instead of allocating a single unused biovec for discard requests, send
them down without any payload.  Instead we allow the driver to add a
"special" payload using a biovec embedded into struct request (unioned
over other fields never used while in the driver), and overloading
the number of segments for this case.

This has a couple of advantages:

 - we don't have to allocate the bio_vec
 - the amount of special casing for discard requests in the block
   layer is significantly reduced
 - using this same scheme for other request types is trivial,
   which will be important for implementing the new WRITE_ZEROES
   op on devices where it actually requires a payload (e.g. SCSI)
 - we can get rid of playing games with the request length, as
   we'll never touch it and completions will work just fine
 - it will allow us to support ranged discard operations in the
   future by merging non-contiguous discard bios into a single
   request
 - last but not least it removes a lot of code

This patch is the common base for my WIP series for ranges discards and to
remove discard_zeroes_data in favor of always using REQ_OP_WRITE_ZEROES,
so it would be good to get it in quickly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-09 08:30:51 -07:00
James Smart 721b3917c4 nvme-fabrics: set sqe.command_id in core not transports
Currently, core.c sets command_id only on rd/wr commands, leaving it to
the transport to set it again to ensure the request had a command id.

Move location of set in core so applies to all commands.
Remove transport sets.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2016-12-06 10:17:03 +02:00
Omar Sandoval bac0000af5 nvme: untangle 0 and BLK_MQ_RQ_QUEUE_OK
Let's not depend on any of the BLK_MQ_RQ_QUEUE_* constants having
specific values. No functional change.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-15 12:50:11 -07:00
Christoph Hellwig 7bf58533a0 nvme: don't pass the full CQE to nvme_complete_async_event
We only need the status and result fields, and passing them explicitly
makes life a lot easier for the Fibre Channel transport which doesn't
have a full CQE for the fast path case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-10 10:06:26 -07:00
Christoph Hellwig d49187e97e nvme: introduce struct nvme_request
This adds a shared per-request structure for all NVMe I/O.  This structure
is embedded as the first member in all NVMe transport drivers request
private data and allows to implement common functionality between the
drivers.

The first use is to replace the current abuse of the SCSI command
passthrough fields in struct request for the NVMe command passthrough,
but it will grow a field more fields to allow implementing things
like common abort handlers in the future.

The passthrough commands are handled by having a pointer to the SQE
(struct nvme_command) in struct nvme_request, and the union of the
possible result fields, which had to be turned from an anonymous
into a named union for that purpose.  This avoids having to pass
a reference to a full CQE around and thus makes checking the result
a lot more lightweight.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-10 10:06:24 -07:00
Christoph Hellwig 7d7e0f90b7 blk-mq: remove ->map_queue
All drivers use the default, so provide an inline version of it.  If we
ever need other queue mapping we can add an optional method back,
although supporting will also require major changes to the queue setup
code.

This provides better code generation, and better debugability as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-15 08:42:03 -06:00
Jay Freyensee eadb7cf441 nvme-loop: set sqsize to 0-based value, per spec
Signed-off-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2016-08-18 09:58:06 +03:00
Sagi Grimberg a159c64d93 nvme-loop: Remove duplicate call to nvme_remove_namespaces
nvme_uninit_ctrl already does that for us. Note that we
reordered nvme_loop_shutdown_ctrl with nvme_uninit_ctrl
but its safe because we want controller uninit to happen
before we shutdown the transport resources.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-08-03 16:25:19 +03:00
Christoph Hellwig 3a85a5de29 nvme-loop: add a NVMe loopback host driver
This patch implements adds nvme-loop which allows to access local devices
exported as NVMe over Fabrics namespaces. This module can be useful for
easy evaluation, testing and also feature experimentation.

To createa nvme-loop device you need to configure the NVMe target to
export a loop port (see the nvmetcli documentaton for that) and then
connect to it using

	nvme connect-all -t loop

which requires the very latest nvme-cli version with Fabrics support.

Signed-off-by: Jay Freyensee <james.p.freyensee@intel.com>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-07-05 11:30:36 -06:00