Commit Graph

121 Commits

Author SHA1 Message Date
Christoph Hellwig
f866fc4282 nvme: move AER handling to common code
The transport driver still needs to do the actual submission, but all the
higher level code can be shared.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:09:26 -06:00
Christoph Hellwig
5955be2144 nvme: move namespace scanning to core
Move the scan work item and surrounding code to the common code.  For now
we need a new finish_scan method to allow the PCI driver to set the
irq affinity hints, but I have plans in the works to obsolete this as well.

Note that this moves the namespace scanning from nvme_wq to the system
workqueue, but as we don't rely on namespace scanning to finish from reset
or I/O this should be fine.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:09:24 -06:00
Christoph Hellwig
92911a55d4 nvme: tighten up state check for namespace scanning
We only should be scanning namespaces if the controller is live.  Currently
we call the function just before setting it live, so fix the code up to
move the call to nvme_queue_scan to just below the state change.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:09:23 -06:00
Christoph Hellwig
bb8d261e08 nvme: introduce a controller state machine
Replace the adhoc flags in the PCI driver with a state machine in the
core code.  Based on code from Sagi Grimberg for the Fabrics driver.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:09:21 -06:00
Christoph Hellwig
04a934d4c7 nvme: remove the io_incapable method
It's unused since "NVMe: Move error handling to failed reset handler".

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jon Derrick <jonathan.derrick@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:09:20 -06:00
Keith Busch
3b24774e1f NVMe: Fix check_flush_dependency warning
If the controller fails and is degraded after a reset, we need to kill
off all requests queues before removing the inaccessble namespaces. This
will prevent del_gendisk from syncing dirty data, which we can't due
from a WQ_MEM_RECLAIM work queue.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-02 09:03:06 -06:00
Guilherme G. Piccoli
c875a7093f nvme: Avoid reset work on watchdog timer function during error recovery
This patch adds a check on nvme_watchdog_timer() function to avoid the
call to reset_work() when an error recovery process is ongoing on
controller. The check is made by looking at pci_channel_offline()
result.

If we don't check for this on nvme_watchdog_timer(), error recovery
mechanism can't recover well, because reset_work() won't be able to
do its job (since we're in the middle of an error) and so the
controller is removed from the system before error recovery mechanism
can perform slot reset (which would allow the adapter to recover).

In this patch we also have split the huge condition expression on
nvme_watchdog_timer() by introducing an auxiliary function to help
make the code more readable.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-13 08:15:39 -06:00
Jens Axboe
7e19793096 NVMe: silence warning about unused 'dev'
Depending on options, we might not be using dev in nvme_cancel_io():

drivers/nvme/host/pci.c: In function ‘nvme_cancel_io’:
drivers/nvme/host/pci.c:970:19: warning: unused variable ‘dev’ [-Wunused-variable]
  struct nvme_dev *dev = data;
                   ^

So get rid of it, and just cast for the dev_dbg_ratelimited() call.

Fixes: 82b4552b91 ("nvme: Use blk-mq helper for IO termination")
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 16:11:11 -06:00
Sagi Grimberg
82b4552b91 nvme: Use blk-mq helper for IO termination
blk-mq offers a tagset iterator so let's use that
instead of using nvme_clear_queues.

Note, we changed nvme_queue_cancel_ios name to nvme_cancel_io
as there is no concept of a queue now in this function (we
also lost the print).

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 15:07:15 -06:00
Keith Busch
21f033f7c7 NVMe: Skip async events for degraded controllers
If the controller is degraded, the driver should stay out of the way so
the user can recover the drive. This patch skips driver initiated async
event requests when the drive is in this state.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Ming Lin
8093f7ca73 nvme: add helper nvme_setup_cmd()
This moves nvme_setup_{flush,discard,rw} calls into a common
nvme_setup_cmd() helper. So we can eventually hide all the command
setup in the core module and don't even need to update the fabrics
drivers for any specific command type.

Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Ming Lin
03b5929ebb nvme: rewrite discard support
This rewrites nvme_setup_discard() with blk_add_request_payload().
It allocates only the necessary amount(16 bytes) for the payload.

Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Ming Lin
58b4560275 nvme: add helper nvme_map_len()
The helper returns the number of bytes that need to be mapped
using PRPs/SGL entries.

Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Ming Lin
2e39e0f608 nvme: add missing lock nesting notation
When unloading driver, nvme_disable_io_queues() calls nvme_delete_queue()
that sends nvme_admin_delete_cq command to admin sq. So when the command
completed, the lock acquired by nvme_irq() actually belongs to admin queue.

While the lock that nvme_del_cq_end() trying to acquire belongs to io queue.
So it will not deadlock.

This patch adds lock nesting notation to fix following report.

[  109.840952] =============================================
[  109.846379] [ INFO: possible recursive locking detected ]
[  109.851806] 4.5.0+ #180 Tainted: G            E
[  109.856533] ---------------------------------------------
[  109.861958] swapper/0/0 is trying to acquire lock:
[  109.866771]  (&(&nvmeq->q_lock)->rlock){-.....}, at: [<ffffffffc0820bc6>] nvme_del_cq_end+0x26/0x70 [nvme]
[  109.876535]
[  109.876535] but task is already holding lock:
[  109.882398]  (&(&nvmeq->q_lock)->rlock){-.....}, at: [<ffffffffc0820c2b>] nvme_irq+0x1b/0x50 [nvme]
[  109.891547]
[  109.891547] other info that might help us debug this:
[  109.898107]  Possible unsafe locking scenario:
[  109.898107]
[  109.904056]        CPU0
[  109.906515]        ----
[  109.908974]   lock(&(&nvmeq->q_lock)->rlock);
[  109.913381]   lock(&(&nvmeq->q_lock)->rlock);
[  109.917787]
[  109.917787]  *** DEADLOCK ***
[  109.917787]
[  109.923738]  May be due to missing lock nesting notation
[  109.923738]
[  109.930558] 1 lock held by swapper/0/0:
[  109.934413]  #0:  (&(&nvmeq->q_lock)->rlock){-.....}, at: [<ffffffffc0820c2b>] nvme_irq+0x1b/0x50 [nvme]
[  109.944010]
[  109.944010] stack backtrace:
[  109.948389] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G            E   4.5.0+ #180
[  109.955734] Hardware name: Dell Inc. OptiPlex 7010/0YXT71, BIOS A15 08/12/2013
[  109.962989]  0000000000000000 ffff88011e203c38 ffffffff81383d9c ffffffff81c13540
[  109.970478]  ffffffff826711d0 ffff88011e203ce8 ffffffff810bb429 0000000000000046
[  109.977964]  0000000000000046 0000000000000000 0000000000b2e597 ffffffff81f4cb00
[  109.985453] Call Trace:
[  109.987911]  <IRQ>  [<ffffffff81383d9c>] dump_stack+0x85/0xc9
[  109.993711]  [<ffffffff810bb429>] __lock_acquire+0x19b9/0x1c60
[  109.999575]  [<ffffffff810b6d1d>] ? trace_hardirqs_off+0xd/0x10
[  110.005524]  [<ffffffff810b386d>] ? complete+0x3d/0x50
[  110.010688]  [<ffffffff810bb760>] lock_acquire+0x90/0xf0
[  110.016029]  [<ffffffffc0820bc6>] ? nvme_del_cq_end+0x26/0x70 [nvme]
[  110.022418]  [<ffffffff81772afb>] _raw_spin_lock_irqsave+0x4b/0x60
[  110.028632]  [<ffffffffc0820bc6>] ? nvme_del_cq_end+0x26/0x70 [nvme]
[  110.035019]  [<ffffffffc0820bc6>] nvme_del_cq_end+0x26/0x70 [nvme]
[  110.041232]  [<ffffffff8135b485>] blk_mq_end_request+0x35/0x60
[  110.047095]  [<ffffffffc0821ad8>] nvme_complete_rq+0x68/0x190 [nvme]
[  110.053481]  [<ffffffff8135b53f>] __blk_mq_complete_request+0x8f/0x130
[  110.060043]  [<ffffffff8135b611>] blk_mq_complete_request+0x31/0x40
[  110.066343]  [<ffffffffc08209e3>] __nvme_process_cq+0x83/0x240 [nvme]
[  110.072818]  [<ffffffffc0820c35>] nvme_irq+0x25/0x50 [nvme]
[  110.078419]  [<ffffffff810cdb66>] handle_irq_event_percpu+0x36/0x110
[  110.084804]  [<ffffffff810cdc77>] handle_irq_event+0x37/0x60
[  110.090491]  [<ffffffff810d0ea3>] handle_edge_irq+0x93/0x150
[  110.096180]  [<ffffffff81012306>] handle_irq+0xa6/0x130
[  110.101431]  [<ffffffff81011abe>] do_IRQ+0x5e/0x120
[  110.106333]  [<ffffffff8177384c>] common_interrupt+0x8c/0x8c

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Keith Busch
788e15abbb NVMe: Always use MSI/MSI-x interrupts
Multiple users have reported device initialization failure due the driver
not receiving legacy PCI interrupts. This is not unique to any particular
controller, but has been observed on multiple platforms.

There have been no issues reported or observed when with message signaled
interrupts, so this patch attempts to use MSI-x during initialization,
falling back to MSI. If that fails, legacy would become the default.

The setup_io_queues error handling had to change as a result: the admin
queue's msix_entry used to be initialized to the legacy IRQ. The case
where nr_io_queues is 0 would fail request_irq when setting up the admin
queue's interrupt since re-enabling MSI-x fails with 0 vectors, leaving
the admin queue's msix_entry invalid. Instead, return success immediately.

Reported-by: Tim Muhlemmer <muhlemmer@gmail.com>
Reported-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-12 13:44:00 -06:00
Marta Rybczynska
d783e0bd02 nvme: avoid cqe corruption when update at the same time as read
Make sure the CQE phase (validity) is read before the rest of the
structure. The phase bit is the highest address and the CQE
read will happen on most platforms from lower to upper addresses
and will be done by multiple non-atomic loads. If the structure
is updated by PCI during the reads from the processor, the
processor may get a corrupted copy.

The addition of the new nvme_cqe_valid function that verifies
the validity bit also allows refactoring of the other CQE read
sequences.

Signed-off-by: Marta Rybczynska <marta.rybczynska@kalray.eu>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-22 10:27:29 -06:00
Linus Torvalds
237045fc3c Merge branch 'for-4.6/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
 "This is the block driver pull request for this merge window.  It sits
  on top of for-4.6/core, that was just sent out.

  This contains:

   - A set of fixes for lightnvm.  One from Alan, fixing an overflow,
     and the rest from the usual suspects, Javier and Matias.

   - A set of fixes for nbd from Markus and Dan, and a fixup from Arnd
     for correct usage of the signed 64-bit divider.

   - A set of bug fixes for the Micron mtip32xx, from Asai.

   - A fix for the brd discard handling from Bart.

   - Update the maintainers entry for cciss, since that hardware has
     transferred ownership.

   - Three bug fixes for bcache from Eric Wheeler.

   - Set of fixes for xen-blk{back,front} from Jan and Konrad.

   - Removal of the cpqarray driver.  It has been disabled in Kconfig
     since 2013, and we were initially scheduled to remove it in 3.15.

   - Various updates and fixes for NVMe, with the most important being:

        - Removal of the per-device NVMe thread, replacing that with a
          watchdog timer instead. From Christoph.

        - Exposing the namespace WWID through sysfs, from Keith.

        - Set of cleanups from Ming Lin.

        - Logging the controller device name instead of the underlying
          PCI device name, from Sagi.

        - And a bunch of fixes and optimizations from the usual suspects
          in this area"

* 'for-4.6/drivers' of git://git.kernel.dk/linux-block: (49 commits)
  NVMe: Expose ns wwid through single sysfs entry
  drivers:block: cpqarray clean up
  brd: Fix discard request processing
  cpqarray: remove it from the kernel
  cciss: update MAINTAINERS
  NVMe: Remove unused sq_head read in completion path
  bcache: fix cache_set_flush() NULL pointer dereference on OOM
  bcache: cleaned up error handling around register_cache()
  bcache: fix race of writeback thread starting before complete initialization
  NVMe: Create discard zero quirk white list
  nbd: use correct div_s64 helper
  mtip32xx: remove unneeded variable in mtip_cmd_timeout()
  lightnvm: generalize rrpc ppa calculations
  lightnvm: remove struct nvm_dev->total_blocks
  lightnvm: rename ->nr_pages to ->nr_sects
  lightnvm: update closed list outside of intr context
  xen/blback: Fit the important information of the thread in 17 characters
  lightnvm: fold get bb tbl when using dual/quad plane mode
  lightnvm: fix up nonsensical configure overrun checking
  xen-blkback: advertise indirect segment support earlier
  ...
2016-03-18 17:13:31 -07:00
Jon Derrick
48c7823f42 NVMe: Remove unused sq_head read in completion path
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-08 15:01:06 -07:00
Keith Busch
08095e7078 NVMe: Create discard zero quirk white list
The NVMe specification does not require discarded blocks return zeroes on
read, but provides that behavior as a possibility. Some applications more
efficiently use an SSD if reads on discarded blocks were deterministically
zero, based on the "discard_zeroes_data" queue attribute.

There is no specification defined way to determine device behavior on
discarded blocks, so the driver always left the queue setting disabled. We
can only know behavior based on individual device models, so this patch
adds a flag to the NVMe "quirk" list that vendors may set if they know
their controller works that way. The patch also sets the new flag for one
such known device.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Suggested-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-08 08:32:40 -07:00
Keith Busch
69d9a99c25 NVMe: Move error handling to failed reset handler
This moves failed queue handling out of the namespace removal path and
into the reset failure path, fixing a hanging condition if the controller
fails or link down during del_gendisk. Previously the driver had to see
the controller as degraded prior to calling del_gendisk to setup the
queues to fail. But, if the controller happened to fail after this,
there was no task to end outstanding requests.

On failure, all namespace states are set to dead. This has capacity
revalidate to 0, and ends all new requests with error status.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03 14:42:50 -07:00
Keith Busch
f58944e265 NVMe: Simplify device reset failure
A reset failure schedules the device to unbind from the driver through
the pci driver's remove. This cleans up all intialization, so there is
no need to duplicate the potentially racy cleanup.

To help understand why a reset failed, the status is logged with the
existing warning message.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03 14:42:49 -07:00
Keith Busch
646017a612 NVMe: Fix namespace removal deadlock
This patch makes nvme namespace removal lockless. It is up to the caller
to ensure no active namespace scanning is occuring. To ensure no scan
work occurs, the nvme pci driver adds a removing state to the controller
device to avoid queueing scan work during removal. The work is flushed
after setting the state, so no new scan work can be queued.

The lockless removal allows the driver to cleanup a namespace
request_queue if the controller fails during removal. Previously this
could deadlock trying to acquire the namespace mutex in order to handle
such events.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03 14:42:49 -07:00
Keith Busch
b00a726a9f NVMe: Don't unmap controller registers on reset
Unmapping the registers on reset or shutdown is not necessary. Keeping
the mapping simplifies reset handling.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03 14:42:49 -07:00
Christoph Hellwig
1cb3cce5eb nvme: return the whole CQE through the request passthrough interface
Both LighNVM and NVMe over Fabrics need to look at more than just the
status and result field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matias Bj?rling <m@bjorling.me>
Reviewed-by: Jay Freyensee <james.p.freyensee@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-29 08:47:17 -07:00
Christoph Hellwig
2d55cd5f51 nvme: replace the kthread with a per-device watchdog timer
The only work left in the kthread is the periodic health check for each
controller.  There is no need to run this from process context or keep
a thread context around for it, so replace it with a simpler timer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-29 08:47:16 -07:00
Christoph Hellwig
79f2b358c9 nvme: don't poll the CQ from the kthread
There is no reason to do unconditional polling of CQs per the NVMe
spec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-29 08:47:14 -07:00
Christoph Hellwig
9396dec916 nvme: use a work item to submit async event requests
Use a dedicated work item to submit async event requests instead of the
global kthread.  This simplifies the code and reduces the latencies to
resubmit a request once an even notification happened.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-29 08:47:13 -07:00
Keith Busch
f8e68a7c9a NVMe: Rate limit nvme IO warnings
We don't need to spam the kernel logs with thousands of IO cancelling
messages. We can infer all IO's are being cancelled with fewer, or
even none at all. This patch rate limits the message and uses the debug
log level as it is mainly used for testing purposes.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-12 08:10:31 -07:00
Keith Busch
ff23a2a15a NVMe: Poll device while still active during remove
A device failure or link down wouldn't have been detected during namespace
removal. This patch keeps the device in the list for polling so that the
thread may see such failure and initiate a reset. The device is removed
from the list after disable, so we can safely flush the reset work as
it can't be requeued when disable completes.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-12 08:10:16 -07:00
Keith Busch
ae1fba2001 NVMe: Requeue requests on suspended queues
It's possible a request may get to the driver after the nvme queue was
disabled. This has the request requeue if that happens.

Note the request is still "started" by the driver, but requeuing will
clear the start state for timeout handling.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-12 08:10:08 -07:00
Ming Lin
576d55d625 nvme: split pci module out of core module
NVMe over Fabrics drivers are going to reuse the core,
so splits nvme.ko into 2 modules:

nvme-core.ko: the core part
nvme.ko: the PCI driver

Export symbols from nvme-core.ko.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-10 14:22:38 -07:00
Ming Lin
9f2482b91b nvme: split dev_list_lock
Split dev_list_lock into one in the core and one in the PCI driver.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-10 14:22:36 -07:00
Ming Lin
ba0ba7d3e5 nvme: move timeout variables to core.c
These variables are used by PCI driver and will also be used in the
forthcoming NVMe over Fabrics drivers.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-10 14:22:34 -07:00
Sagi Grimberg
e439bb12e7 nvme/host: reference the fabric module for each bdev open callout
We don't want to be able to unload the fabric driver when we have
openened referenced to our namespaces. Thus, for each nvme_open we
take a reference on the fabric driver and put it in nvme_release.
This behavior is consistent with the scsi model.

This resolves the panic when unloading a fabric module with
mpath holders.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ian Bakshan <ianb@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-10 14:22:32 -07:00
Sagi Grimberg
1b3c47c182 nvme: Log the ctrl device name instead of the underlying pci device name
Having the ctrl name "nvmeX" seems much more friendly than
the underlying device name. Also, with other nvme transports
such as the soon to come nvme-loop we don't have an underlying
device so it doesn't makes sense to make up one.

In order to help matching an instance name to a pci function,
we add a info print in nvme_probe.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Acked-by: Keith Busch <keith.busch@intel.com>

Manually fixed up the hunk in nvme_cancel_queue_ios().

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-10 08:51:15 -07:00
Keith Busch
949928c1c7 NVMe: Fix possible queue use after freed
This notifies blk-mq when the tag set contains a different number of
queues prior to freeing unused ones that the request queue points to.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-09 12:42:35 -07:00
Linus Torvalds
3e1e21c7bf Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-block
Pull NVMe updates from Jens Axboe:
 "Last branch for this series is the nvme changes.  It's in a separate
  branch to avoid splitting too much between core and NVMe changes,
  since NVMe is still helping drive some blk-mq changes.  That said, not
  a huge amount of core changes in here.  The grunt of the work is the
  continued split of the code"

* 'for-4.5/nvme' of git://git.kernel.dk/linux-block: (67 commits)
  uapi: update install list after nvme.h rename
  NVMe: Export NVMe attributes to sysfs group
  NVMe: Shutdown controller only for power-off
  NVMe: IO queue deletion re-write
  NVMe: Remove queue freezing on resets
  NVMe: Use a retryable error code on reset
  NVMe: Fix admin queue ring wrap
  nvme: make SG_IO support optional
  nvme: fixes for NVME_IOCTL_IO_CMD on the char device
  nvme: synchronize access to ctrl->namespaces
  nvme: Move nvme_freeze/unfreeze_queues to nvme core
  PCI/AER: include header file
  NVMe: Export namespace attributes to sysfs
  NVMe: Add pci error handlers
  block: remove REQ_NO_TIMEOUT flag
  nvme: merge iod and cmd_info
  nvme: meta_sg doesn't have to be an array
  nvme: properly free resources for cancelled command
  nvme: simplify completion handling
  nvme: special case AEN requests
  ...
2016-01-21 19:58:02 -08:00
Linus Torvalds
7c24d9f3b2 Merge branch 'for-4.5/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
 "We don't have a lot of core changes this time around, it's mostly in
  drivers, which will come in a subsequent pull.

  The cores changes include:

   - blk-mq
        - Prep patch from Christoph, changing blk_mq_alloc_request() to
          take flags instead of just using gfp_t for sleep/nosleep.
        - Doc patch from me, clarifying the difference between legacy
          and blk-mq for timer usage.
        - Fixes from Raghavendra for memory-less numa nodes, and a reuse
          of CPU masks.

   - Cleanup from Geliang Tang, using offset_in_page() instead of open
     coding it.

   - From Ilya, rename request_queue slab to it reflects what it holds,
     and a fix for proper use of bdgrab/put.

   - A real fix for the split across stripe boundaries from Keith.  We
     yanked a broken version of this from 4.4-rc final, this one works.

   - From Mike Krinkin, emit a trace message when we split.

   - From Wei Tang, two small cleanups, not explicitly clearing memory
     that is already cleared"

* 'for-4.5/core' of git://git.kernel.dk/linux-block:
  block: use bd{grab,put}() instead of open-coding
  block: split bios to max possible length
  block: add call to split trace point
  blk-mq: Avoid memoryless numa node encoded in hctx numa_node
  blk-mq: Reuse hardware context cpumask for tags
  blk-mq: add a flags parameter to blk_mq_alloc_request
  Revert "blk-flush: Queue through IO scheduler when flush not required"
  block: clarify blk_add_timer() use case for blk-mq
  bio: use offset_in_page macro
  block: do not initialise statics to 0 or NULL
  block: do not initialise globals to 0 or NULL
  block: rename request_queue slab cache
2016-01-19 15:03:34 -08:00
Keith Busch
a5cdb68c2c NVMe: Shutdown controller only for power-off
We don't need to shutdown a controller for a reset. A controller in a
shutdown state may take longer to become ready than one that was simply
disabled. This patch has the driver shut down a controller only if the
device is about to be powered off or being removed. When taking the
controller down for a reset reason, the controller will be disabled
instead.

Function names have been updated in this patch to reflect their changed
semantics.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 14:47:59 -07:00
Keith Busch
db3cbfff5b NVMe: IO queue deletion re-write
The nvme driver deletes IO queues asynchronously since this operation
may potentially take an undesirable amount of time with a large number
of queues if done serially.

The driver used to manage coordinating asynchronous deletions. This
patch simplifies that by leveraging the block layer rather than using
kthread workers and chaining more complicated callbacks.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 14:47:56 -07:00
Keith Busch
25646264e1 NVMe: Remove queue freezing on resets
NVMe submits all commands through the block layer now. This means we
can let requests queue at the blk-mq hardware context since there is no
path that bypasses this anymore so we don't need to freeze the queues
anymore. The driver can simply stop the h/w queues from running during
a reset instead.

This also fixes a WARN in percpu_ref_reinit when the queue was unfrozen
with requeued requests.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 13:33:36 -07:00
Keith Busch
1d49c38c48 NVMe: Use a retryable error code on reset
A negative status has the "do not retry" bit set, which makes it not
retryable.  Use a fake status that can potentially be retried on reset.

An aborted command's status is overridden by the timeout handler so
that it won't be retried, which is necessary to keep initialization from
getting into a reset loop.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 13:33:35 -07:00
Keith Busch
e3e9d50cd6 NVMe: Fix admin queue ring wrap
The tag set queue depth needs to be one less than the h/w queue depth
so we don't wrap the circular buffer. This conforms to the specification
defined "Full Queue" condition.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 13:33:33 -07:00
Sagi Grimberg
363c9aacb6 nvme: Move nvme_freeze/unfreeze_queues to nvme core
Nothing pci specific about them and We'll need them exported
in other transports too.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12 13:30:11 -07:00
Keith Busch
b5875222de NVMe: IO ending fixes on surprise removal
This patch fixes a lost request discovered during IO + hot removal.

The driver's pci removal deletes gendisks prior to shutting down the
controller to allow dirty data to sync. Dirty data can not be synced on
a surprise removal, though, and would potentially block indefinitely.

The driver previously had marked the queue as dying in this scenario
to prevent new requests from attempting, however it will still block
for requests that already entered the queue. This patch fixes this by
quiescing IO first, then aborting the requeued requests before deleting
disks.

Reported-by: Sujith Pandel <sujith_pandel@dell.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Tested-by: Sujith Pandel <sujith_pandel@dell.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 10:12:04 -07:00
Keith Busch
a0a3408ee6 NVMe: Add pci error handlers
Requests enabling pcie aer support. Shuts down the controller on error
detected with io frozen state prior to requesting slot reset; resumes
controller after reset completes.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 10:09:06 -07:00
Christoph Hellwig
f4800d6d15 nvme: merge iod and cmd_info
Merge the two per-request structures in the nvme driver into a single
one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 09:38:34 -07:00
Christoph Hellwig
bf68405705 nvme: meta_sg doesn't have to be an array
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 09:38:34 -07:00
Christoph Hellwig
eee417b069 nvme: properly free resources for cancelled command
We need to move freeing of resources to the ->complete handler to ensure
they are also freed when we cancel the command.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 09:38:34 -07:00
Christoph Hellwig
aae239e191 nvme: simplify completion handling
Now that all commands are executed as block layer requests we can remove the
internal completion in the NVMe driver.  Note that we can simply call
blk_mq_complete_request to abort commands as the block layer will protect
against double copletions internally.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22 09:38:34 -07:00