The variable 'ctrl' became useless since the code using it was dropped
from nvme_setup_cmd() in the commit 292ddf67bbd5 ("nvme: increment
request genctr on completion"). Fix it to get rid of this compilation
warning in the nvme-5.17 branch:

 drivers/nvme/host/core.c: In function ‘nvme_setup_cmd’:
 drivers/nvme/host/core.c:993:20: warning: unused variable ‘ctrl’ [-Wunused-variable]
   struct nvme_ctrl *ctrl = nvme_req(req)->ctrl;
                     ^~~~

Fixes: 292ddf67bbd5 ("nvme: increment request genctr on completion")
Signed-off-by: NGeliang Tang <geliang.tang@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The nvme request generation counter is intended to catch duplicate
completions. Incrementing the counter on submission means duplicates can
only be caught if the request tag is reallocated and dispatched prior to
the driver observing the corrupted CQE. Incrementing on completion
removes this window, making it possible to detect duplicate completions
in consecutive entries.
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Remove the gendisk aregument to blk_execute_rq and blk_execute_rq_nowait
given that it is unused now.  Also convert the boolean at_head parameter
to actually use the bool type while touching the prototype.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211126121802.2090656-5-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Write Zeroes sets PRACT when block integrity is enabled (as it should),
but neglects to also set the reftag which is expected by reads. This
causes protection errors on reads.

Fix this by setting the reftag for type 1 and 2 (for type 3, reads will
not check the reftag).
Signed-off-by: NKlaus Jensen <k.jensen@samsung.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This particular Kioxia device times out and aborts I/O during any load,
but it's more easily observable with discards (fstrim).

The device gets to a state that is also not possible to use
"nvme set-feature" to disable APST.
Booting with nvme_core.default_ps_max_latency=0 solves the issue.

We had a dozen or so of these devices behaving this same way in
customer environments.
Signed-off-by: NEnzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

NVMe uses one atomic flag to check if quiesce is needed. If quiesce is
started, the helper returns immediately. This way is wrong, since we
have to wait until quiesce is done.

Fixes: e70feb8b ("blk-mq: support concurrent queue quiesce/unquiesce")
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211109071144.181581-5-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

With discovery controllers supporting unique subsystem NQNs the
actual subsystem NQN might be different from that one passed in
via the connect args. So add a helper to display the resulting
subsystem NQN.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Add a connect option 'discovery' to specify that the connection
should be made to a discovery controller, not a normal I/O controller.
With discovery controllers supporting unique subsystem NQNs we
cannot easily distinguish by the subsystem NQN if this should be
a discovery connection, but we need this information to blank out
options not supported by discovery controllers.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

With unique discovery controller NQNs we cannot distinguish the
subsystem type by the NQN alone, but need to check the subsystem
type, too.
So expose the subsystem type in a new sysfs attribute 'subsystype'.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The current blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() always
stops and starts the queue unconditionally. And there can be concurrent
quiesce/unquiesce coming from different unrelated code paths, so
unquiesce may come unexpectedly and start queue too early.

Prepare for supporting concurrent quiesce/unquiesce from multiple
contexts, so that we can address the above issue.

NVMe has very complicated quiesce/unquiesce use pattern, add one atomic
bit for makeiing sure that blk-mq quiece/unquiesce is always called in
pair.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-5-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add two helpers so that we can prepare for pairing quiescing and
unquiescing which will be done in next patch.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-4-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Apply the added two APIs to quiesce/unquiesce admin queue.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-3-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add two APIs for stopping and starting admin queue.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-2-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

This memset in the fast path costs a lot of cycles on my setup. Here's a
top-of-profile of doing ~6.7M IOPS:

+    5.90%  io_uring  [nvme]            [k] nvme_queue_rq
+    5.32%  io_uring  [nvme_core]       [k] nvme_setup_cmd
+    5.17%  io_uring  [kernel.vmlinux]  [k] io_submit_sqes
+    4.97%  io_uring  [kernel.vmlinux]  [k] blkdev_direct_IO

and a perf diff with this patch:

     0.92%     +4.40%  [nvme_core]       [k] nvme_setup_cmd

reducing it from 5.3% to only 0.9%. This takes it from the 2nd most
cycle consumer to something that's mostly irrelevant.
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We don't have to worry about doing extra memsets by moving it outside
the protection of RQF_DONTPREP, as nvme doesn't do partial completions.

This is in preparation for making the read/write fast path not do a full
memset of the command.
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Take advantage of struct io_comp_batch, if passed in to the nvme poll
handler. If it's set, rather than complete each request individually
inline, store them in the io_comp_batch list. We only do so for requests
that will complete successfully, anything else will be completed inline as
before.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Unlike the RWF_HIPRI userspace ABI which is intentionally kept vague,
the bio flag is specific to the polling implementation, so rename and
document it properly.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Tested-by: NMark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-12-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Split the integrity/metadata handling definitions out into a new header.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-17-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Decrease reference count of chardevice during char device deletion in
order to fix a memory leak.  Add a release callabck for the device
associated chardev and move ida_simple_remove into the release function.

Fixes: 2637baed ("nvme: introduce generic per-namespace chardev")
Reported-by: NYi Zhang <yi.zhang@redhat.com>
Suggested-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NAdam Manzanares <a.manzanares@samsung.com>
Reviewed-by: NJavier González <javier@javigon.com>
Tested-by: NYi Zhang <yi.zhang@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Some apple controllers use the command id as an index to implementation
specific data structures and will fail if the value is out of bounds.
The nvme driver's recently introduced command sequence number breaks
this controller.

Provide a quirk so these spec incompliant controllers can function as
before. The driver will not have the ability to detect bad completions
when this quirk is used, but we weren't previously checking this anyway.

The quirk bit was selected so that it can readily apply to stable.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214509
Cc: Sven Peter <sven@svenpeter.dev>
Reported-by: NOrlando Chamberlain <redecorating@protonmail.com>
Reported-by: NAditya Garg <gargaditya08@live.com>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NSven Peter <sven@svenpeter.dev>
Link: https://lore.kernel.org/r/20210927154306.387437-1-kbusch@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

Various places in the nvme code that rely on ctrl->namespace to be
ordered.  Ensure that the namespae is inserted into the list at the
right position from the start instead of sorting it after the fact.

Fixes: 540c801c ("NVMe: Implement namespace list scanning")
Reported-by: NAnton Eidelman <anton.eidelman@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: NDamien Le Moal <damien.lemoal@wdc.com>

There is no need to explicitly unregister the integrity profile when
deleting the gendisk.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20210914070657.87677-4-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

When we remove the siblings entry, we update ns->head->list, hence we
can't separate the removal and test for being empty. They have to be
in the same critical section to avoid a race.

To avoid breaking the refcounting imbalance again, add a list empty
check to nvme_find_ns_head.

Fixes: 5396fdac ("nvme: fix refcounting imbalance when all paths are down")
Signed-off-by: NDaniel Wagner <dwagner@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Tested-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The function nmve_mpath_clear_current_path returns true if the current
path has changed. In this case we have to wait for all concurrent
submissions to finish. But if we didn't change the current path, there
is no point in waiting for another RCU period to finish.
Signed-off-by: NDaniel Wagner <dwagner@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Currently the connection between host and NVMe-oF target gets
disconnected by keep-alive timeout when a user connects to a target
with a relatively large kato value and then sets the smaller kato
with a set features command (e.g. connects with 60 seconds kato value
and then sets 10 seconds kato value).

The cause is that keep alive command interval on the host, which is
defined as unsigned int kato in nvme_ctrl structure, does not follow
the kato value changes.

This patch updates the keep alive interval in the following steps when
the kato is modified by a set features command: stops the keep alive
work queue, then sets the kato as new timer value and re-start the queue.
Signed-off-by: NTatsuya Sasaki <tatsuya6.sasaki@kioxia.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Preparatory patch in order to reuse nvme_multi_css in the nvme target
code.
Signed-off-by: NAdam Manzanares <a.manzanares@samsung.com>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

When triggering a rescan due to a namespace resize we will be
receiving AENs on every controller, triggering a rescan of all
attached namespaces. If multipath is active only the current path and
the ns_head disk will be updated, the other paths will still refer to
the old size until AENs for the remaining controllers are received.

If I/O comes in before that it might be routed to one of the old
paths, triggering an I/O failure with 'access beyond end of device'.
With this patch the old paths are skipped from multipath path
selection until the controller serving these paths has been rescanned.
Signed-off-by: NHannes Reinecke <hare@suse.de>
[dwagner: - introduce NVME_NS_READY flag instead of NVME_NS_INVALIDATE
          - use 'revalidate' instead of 'invalidate' which
	    follows the zoned device code path.
	  - clear NVME_NS_READY before clearing current_path]
Signed-off-by: NDaniel Wagner <dwagner@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Switch to use the blk_mq_alloc_disk helper for allocating the
request_queue and gendisk.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20210816131910.615153-2-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Use bvec_virt instead of open coding it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20210804095634.460779-16-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

We cannot detect a (perhaps buggy) controller that is sending us
a completion for a request that was already completed (for example
sending a completion twice), this phenomenon was seen in the wild
a few times.

So to protect against this, we use the upper 4 msbits of the nvme sqe
command_id to use as a 4-bit generation counter and verify it matches
the existing request generation that is incrementing on every execution.

The 16-bit command_id structure now is constructed by:
| xxxx | xxxxxxxxxxxx |
  gen    request tag

This means that we are giving up some possible queue depth as 12 bits
allow for a maximum queue depth of 4095 instead of 65536, however we
never create such long queues anyways so no real harm done.
Suggested-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Acked-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NDaniel Wagner <dwagner@suse.de>
Tested-by: NDaniel Wagner <dwagner@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Lightnvm supports the OCSSD 1.x and 2.0 specs which were early attempts
to produce Open Channel SSDs and never made it into the NVMe spec
proper.  They have since been superceeded by NVMe enhancements such
as ZNS support.  Remove the support per the deprecation schedule.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210812132308.38486-1-hch@lst.deReviewed-by: NMatias Bjørling <mb@lightnvm.io>
Reviewed-by: NJavier González <javier@javigon.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Just check inode_unhashed on the whole device bdev inode instead,
and provide a helper to check for that information.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210809064028.1198327-9-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Early probe failure never reaches nvme_ns_remove, so GENHD_FL_UP must
be set at this point.  Remove the check.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210809064028.1198327-4-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

.. and rename the function to disk_update_readahead.  This is in
preparation for moving the BDI from the request_queue to the gendisk.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-3-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

When using Write Zeroes on a namespace that has protection
information enabled they behavior without the PRACT bit
counter-intuitive and will generally lead to validation failures
when reading the written blocks.  Fix this by always setting the
PRACT bit that generates matching PI data on the fly.

Fixes: 6e02318e ("nvme: add support for the Write Zeroes command")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>

When the last path to a ns_head drops the current code
removes the ns_head from the subsystem list, but will only
delete the disk itself if the last reference to the ns_head
drops. This is causing an refcounting imbalance eg when
applications have a reference to the disk, as then they'll
never get notified that the disk is in fact dead.
This patch moves the call 'del_gendisk' into nvme_mpath_check_last_path(),
ensuring that the disk can be properly removed and applications get the
appropriate notifications.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We don't have an nvme status to report if the driver's .queue_rq()
returns an error without dispatching the requested nvme command. Check
the return value from blk_execute_rq() for all passthrough commands so
the caller may know their command was not successful.

If the command is from the target passthrough interface and fails to
dispatch, synthesize the response back to the host as a internal target
error.
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210610214437.641245-5-kbusch@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

The generic blk_execute_rq() knows how to handle polled completions. Use
that instead of implementing an nvme specific handler.
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210610214437.641245-3-kbusch@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

Declare and initialize structure variables to zero values so that we can
remove zeroout memset calls in the host/core.c.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>