We will need to reference the controller in the setup and completion
time for tracing and future traffic based keep alive support.
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

nvme requires an sg table allocation for each request. If the request
is large, then the allocation can become quite large. For instance,
with our default software settings of 1280KB IO size, we'll need
10248 bytes of sg table. That turns into a 2nd order allocation,
which we can't always guarantee. If we fail the allocation, blk-mq
will retry it later. But there's no guarantee that we'll EVER be
able to allocate that much contigious memory.

Limit the IO size such that we never need more than a single page
of memory. That's a lot faster and more reliable. Then back that
allocation with a mempool, so that we know we'll always be able
to succeed the allocation at some point.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

There is race between nvme_remove and nvme_reset_work that can
lead to io hang.

nvme_remove                    nvme_reset_work
                               -> nvme_remove_dead_ctrl
                                 -> nvme_dev_disable
                                   -> quiesce request_queue
                                 -> queue remove_work
-> cancel_work_sync reset_work
-> nvme_remove_namespaces
  -> splice ctrl->namespaces
                               nvme_remove_dead_ctrl_work
                               -> nvme_kill_queues
  -> nvme_ns_remove               do nothing
    -> blk_cleanup_queue
      -> blk_freeze_queue

Finally, the request_queue is quiesced state when wait freeze,
we will get io hang here. To fix it, move the nvme_kill_queues
from nvme_remove_dead_ctrl_work to nvme_remove_dead_ctrl.
Suggested-by: NKeith Busch <keith.busch@linux.intel.com>
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

A controller reset after a run time change of the CMB module parameter
breaks the driver. An 'on -> off' will have the driver use NULL for the
host memory queue, and 'off -> on' will use mismatched queue depth between
the device and the host.

We could fix both, but there isn't really a good reason to change this
at run time anyway, compared to at module load time, so this patch makes
parameter read-only after after modprobe.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch ensures the nvme namsepace request queues are not quiesced
on a surprise removal. It's possible the queues were previously killed
in a failed reset, so the queues need to be unquiesced to ensure all
requests are flushed to completion.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The controller is required to disable its host memory buffer use on
controller reset. We don't need to submit an admin command to delete it,
so this patch skips sending that command so we don't need to worry about
handling a timeout.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We've been ignoring NVMe error status on queue creations. Fortunately they
are uncommon, but we should handle these anyway. This patch adds checks
for the a positive error return value that indicates an NVMe status.

If we do see a negative return, the controller isn't usable, so this
patch returns immediately in since we can't unwind that failure.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The nvme pci driver never unmaps the doorbell registers while the requests
are active, so we can always safely update the completion queue head.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The nvme pci driver no longer handles completions under the cq lock,
so the nested locking is not necessary.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

With recent CQ handling improvements we can now move the locking into
__nvme_submit_cmd.  Also remove the local tail variable to make the code
more obvious, remove the __ prefix in the name, and fix the comments
describing the function.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>

The block layer's timeout handling currently prevents drivers from
completing commands outside the timeout callback once blk-mq decides
they've expired. If a device breaks, this could potentially create many
thousands of timed out commands. There's nothing of value to be gleaned
from observing each of those messages, so this patch adds a rate limit
on them.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

NVMe always completes the request before returning from ->timeout, either
by polling for it, or by disabling the controller.  Return BLK_EH_DONE so
that the block layer doesn't even try to complete it again.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The nvme timeout handling doesn't do anything if the pci channel is
offline, which is the case when recovering from PCI error event, so it
was a bad idea to sync the controller reset in this state. This patch
flushes the reset work in the error_resume callback instead when the
channel is back to online. This keeps AER handling serialized and
can recover from timeouts.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199757
Fixes: cc1d5e74 ("nvme/pci: Sync controller reset for AER slot_reset")
Reported-by: NAlex Gagniuc <mr.nuke.me@gmail.com>
Tested-by: NAlex Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Set cq_vector after alloc cq/sq, otherwise nvme_suspend_queue will invoke
free_irq for it and cause a 'Trying to free already-free IRQ  xxx'
warning if the create CQ/SQ command times out.
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
[hch: fixed to pass a s16 and clean up the comment]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

If polling completions are racing with the IRQ triggered by a
completion, the IRQ handler will find no work and return IRQ_NONE.
This can trigger complaints about spurious interrupts:

[  560.169153] irq 630: nobody cared (try booting with the "irqpoll" option)
[  560.175988] CPU: 40 PID: 0 Comm: swapper/40 Not tainted 4.17.0-rc2+ #65
[  560.175990] Hardware name: Intel Corporation S2600STB/S2600STB, BIOS SE5C620.86B.00.01.0010.010920180151 01/09/2018
[  560.175991] Call Trace:
[  560.175994]  <IRQ>
[  560.176005]  dump_stack+0x5c/0x7b
[  560.176010]  __report_bad_irq+0x30/0xc0
[  560.176013]  note_interrupt+0x235/0x280
[  560.176020]  handle_irq_event_percpu+0x51/0x70
[  560.176023]  handle_irq_event+0x27/0x50
[  560.176026]  handle_edge_irq+0x6d/0x180
[  560.176031]  handle_irq+0xa5/0x110
[  560.176036]  do_IRQ+0x41/0xc0
[  560.176042]  common_interrupt+0xf/0xf
[  560.176043]  </IRQ>
[  560.176050] RIP: 0010:cpuidle_enter_state+0x9b/0x2b0
[  560.176052] RSP: 0018:ffffa0ed4659fe98 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
[  560.176055] RAX: ffff9527beb20a80 RBX: 000000826caee491 RCX: 000000000000001f
[  560.176056] RDX: 000000826caee491 RSI: 00000000335206ee RDI: 0000000000000000
[  560.176057] RBP: 0000000000000001 R08: 00000000ffffffff R09: 0000000000000008
[  560.176059] R10: ffffa0ed4659fe78 R11: 0000000000000001 R12: ffff9527beb29358
[  560.176060] R13: ffffffffa235d4b8 R14: 0000000000000000 R15: 000000826caed593
[  560.176065]  ? cpuidle_enter_state+0x8b/0x2b0
[  560.176071]  do_idle+0x1f4/0x260
[  560.176075]  cpu_startup_entry+0x6f/0x80
[  560.176080]  start_secondary+0x184/0x1d0
[  560.176085]  secondary_startup_64+0xa5/0xb0
[  560.176088] handlers:
[  560.178387] [<00000000efb612be>] nvme_irq [nvme]
[  560.183019] Disabling IRQ #630

A previous commit removed ->cqe_seen that was handling this case,
but we need to handle this a bit differently due to completions
now running outside the queue lock. Return IRQ_HANDLED from the
IRQ handler, if the completion ring head was moved since we last
saw it.

Fixes: 5cb525c8 ("nvme-pci: handle completions outside of the queue lock")
Reported-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Tested-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Since we aren't sharing the lock for completions now, we don't
have to make it IRQ safe.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This is now feasible. We protect the submission queue ring with
->sq_lock, and the completion side with ->cq_lock.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Split the completion of events into a two part process:

1) Reap the events inside the queue lock
2) Complete the events outside the queue lock

Since we never wrap the queue, we can access it locklessly after we've
updated the completion queue head. This patch started off with batching
events on the stack, but with this trick we don't have to. Keith Busch
<keith.busch@intel.com> came up with that idea.

Note that this kills the ->cqe_seen as well. I haven't been able to
trigger any ill effects of this. If we do race with polling every so
often, it should be rare enough NOT to trigger any issues.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
[hch: refactored, restored poll early exit optimization]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We only clear it dynamically in nvme_suspend_queue(). When we do, ensure
to do a full flush so that any nvme_queue_rq() invocation will see it.

Ideally we'd kill this check completely, but we're using it to flush
requests on a dying queue.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We always check the completion queue after submitting, but in my testing
this isn't a win even on DRAM/xpoint devices. In some cases it's
actually worse. Kill it.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We always look at the current CQ head and phase, so don't pass these
as separate arguments, and rename the function to nvme_cqe_pending.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

AER handling expects a successful return from slot_reset means the
driver made the device functional again. The nvme driver had been using
an asynchronous reset to recover the device, so the device
may still be initializing after control is returned to the
AER handler. This creates problems for subsequent event handling,
causing the initializion to fail.

This patch fixes that by syncing the controller reset before returning
to the AER driver, and reporting the true state of the reset.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199657Reported-by: NAlex Gagniuc <mr.nuke.me@gmail.com>
Cc: Sinan Kaya <okaya@codeaurora.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Tested-by: NAlex Gagniuc <mr.nuke.me@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

Some P3100 drives have a bug where they think WRRU (weighted round robin)
is always enabled, even though the host doesn't set it. Since they think
it's enabled, they also look at the submission queue creation priority. We
used to set that to MEDIUM by default, but that was removed in commit
81c1cd98. This causes various issues on that drive. Add a quirk to
still set MEDIUM priority for that controller.

Fixes: 81c1cd98 ("nvme/pci: Don't set reserved SQ create flags")
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

It is possible the driver's remove may have freed the controller if
the remove callback is invoked prior to the async_schedule starting
the reset_work. This patch fixes that by holding a reference on the
controller.
Reported-by: NMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

This patch schedules the initial controller reset in an async_domain
so that it can be synchronized from wait_for_device_probe(). This way
the kernel waits for the initial nvme controller scan to complete for
all devices before proceeding with the boot sequence, which may have
nvme dependencies.
Reported-by: NMikulas Patocka <mpatocka@redhat.com>
Tested-by: NMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

Add a new lightnvm quirk to identify CNEX’s Granby controller.
Signed-off-by: NWei Xu <wxu@cnexlabs.com>
Reviewed-by: NJavier González <javier@cnexlabs.com>
Reviewed-by: NMatias Bjørling <mb@lightnvm.io>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

Add Seagate Nytro Flash Storage nvme drive to quirk list for
NVME_QUIRK_DELAY_BEFORE_CHK_RDY, which solves a bug where the drive is
probed on hot-add before the firmare is ready, I/O errors are generated
while reading sector 0, and linux is "unable to read partition table".
Signed-off-by: NMicah Parrish <micah.parrish@hpe.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

Instead of implementing our own version of a SR-IOV configuration stub in
the nvme driver, use the existing pci_sriov_configure_simple() function.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

The admin and first IO queues shared the first irq vector, which has an
affinity mask including cpu0. If a system allows cpu0 to be offlined,
the admin queue may not be usable if no other CPUs in the affinity mask
are online. This is a problem since unlike IO queues, there is only
one admin queue that always needs to be usable.

To fix, this patch allocates one pre_vector for the admin queue that
is assigned all CPUs, so will always be accessible. The IO queues are
assigned the remaining managed vectors.

In case a controller has only one interrupt vector available, the admin
and IO queues will share the pre_vector with all CPUs assigned.

Cc: Jianchao Wang <jianchao.w.wang@oracle.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

All the queue memory is allocated up front. We don't take the node
into consideration when creating queues anymore, so removing the unused
parameter.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

User reported controller always retains CSTS.RDY to 1, which fails
controller disabling when resetting the controller. This is also before
the admin queue is allocated, and trying to disable an unallocated queue
results in a NULL dereference.
Reported-by: NAlex Gagniuc <Alex_Gagniuc@Dellteam.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The PCI interrupt vectors intended to be associated with a queue may
not start at 0; a driver may allocate pre_vectors for special use. This
patch adds an offset parameter so blk-mq may find the intended affinity
mask and updates all drivers using this API accordingly.

Cc: Don Brace <don.brace@microsemi.com>
Cc: <qla2xxx-upstream@qlogic.com>
Cc: <linux-scsi@vger.kernel.org>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Yet another "incompatible" Samsung NVMe SSD 960 EVO and Asus motherboard
combination. 960 EVO device disappears from PCIe bus within few minutes
after boot-up when APST is in use and never gets back. Forcing
NVME_QUIRK_NO_APST is the only way to make this drive work with this
particular motherboard. NVME_QUIRK_NO_DEEPEST_PS doesn't work, upgrading
motherboard's BIOS didn't help either.
Since this is a desktop motherboard, the only drawback of not using APST
is increased device temperature.
Signed-off-by: NJarosław Janik <jaroslaw.janik@gmail.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The nvme-fabrics exports the controller address to sysfs, and we'd
like to have parity with this feature for PCIe. This patch provides
the appropiate callback and returns the controller address as the pci
domain:bus:device.function.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Quiesce IO queues prior to disabling device HMB accesses. A controller
using HMB may relay on it to efficiently complete IO commands.
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

84676c1f ("genirq/affinity: assign vectors to all possible CPUs")
has switched to do irq vectors spread among all possible CPUs, so
pass num_possible_cpus() as max vecotrs to be assigned.

For example, in a 8 cores system, 0~3 online, 4~8 offline/not present,
see 'lscpu':

        [ming@box]$lscpu
        Architecture:          x86_64
        CPU op-mode(s):        32-bit, 64-bit
        Byte Order:            Little Endian
        CPU(s):                4
        On-line CPU(s) list:   0-3
        Thread(s) per core:    1
        Core(s) per socket:    2
        Socket(s):             2
        NUMA node(s):          2
        ...
        NUMA node0 CPU(s):     0-3
        NUMA node1 CPU(s):
        ...

1) before this patch, follows the allocated vectors and their affinity:
	irq 47, cpu list 0,4
	irq 48, cpu list 1,6
	irq 49, cpu list 2,5
	irq 50, cpu list 3,7

2) after this patch, follows the allocated vectors and their affinity:
	irq 43, cpu list 0
	irq 44, cpu list 1
	irq 45, cpu list 2
	irq 46, cpu list 3
	irq 47, cpu list 4
	irq 48, cpu list 6
	irq 49, cpu list 5
	irq 50, cpu list 7

Cc: Keith Busch <keith.busch@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>

Triggering PPC EEH detection and handling requires a memory mapped read
failure. The NVMe driver removed the periodic health check MMIO, so
there's no early detection mechanism to trigger the recovery. Instead,
the detection now happens when the nvme driver handles an IO timeout
event. This takes the pci channel offline, so we do not want the driver
to proceed with escalating its own recovery efforts that may conflict
with the EEH handler.

This patch ensures the driver will observe the channel was set to offline
after a failed MMIO read and resets the IO timer so the EEH handler has
a chance to recover the device.
Signed-off-by: NWen Xiong <wenxiong@linux.vnet.ibm.com>
[updated change log]
Signed-off-by: NKeith Busch <keith.busch@intel.com>

This patch fixes nvme queue cleanup if requesting an IRQ handler for
the queue's vector fails. It does this by resetting the cq_vector to
the uninitialized value of -1 so it is ignored for a controller reset.
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
[changelog updates, removed misc whitespace changes]
Signed-off-by: NKeith Busch <keith.busch@intel.com>

We need to halt the controller immediately if we haven't completed
initialization as indicated by the new "connecting" state.

Fixes: ad70062c ("nvme-pci: introduce RECONNECTING state to mark initializing procedure")
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

The controller memory buffer is remapped into a kernel address on each
reset, but the driver was setting the submission queue base address
only on the very first queue creation. The remapped address is likely to
change after a reset, so accessing the old address will hit a kernel bug.

This patch fixes that by setting the queue's CMB base address each time
the queue is created.

Fixes: f63572df ("nvme: unmap CMB and remove sysfs file in reset path")
Reported-by: NChristian Black <christian.d.black@intel.com>
Cc: Jon Derrick <jonathan.derrick@intel.com>
Cc: <stable@vger.kernel.org> # 4.9+
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>