The NVMe over Fabrics specification defines a protocol interface and
related extensions to NVMe that enable operation over network protocols.
The NVMe over Fabrics specification has an NVMe Transport binding for
each NVMe Transport.

This patch adds the fabrics related definitions:
- fabric specific command set and error codes
- transport addressing and binding definitions
- fabrics sgl extensions
- controller identification fabrics enhancements
- discovery log page definition
Signed-off-by: NArmen Baloyan <armenx.baloyan@intel.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NJay Freyensee <james.p.freyensee@intel.com>
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

- delete_controller: This attribute allows to delete a controller.
  A driver is not obligated to support it (pci doesn't) so it is
  created only if the driver supports it. The new fabrics drivers
  will support it (essentialy a disconnect operation).

  Usage:
  echo > /sys/class/nvme/nvme0/delete_controller

- subsysnqn: This attribute shows the subsystem nqn of the configured
  device. If a driver does not implement the get_subsysnqn method, the
  file will not appear in sysfs.

- transport: This attribute shows the transport name. Added a "name"
  field to struct nvme_ctrl_ops.

  For loop,
  cat /sys/class/nvme/nvme0/transport
  loop

  For RDMA,
  cat /sys/class/nvme/nvme0/transport
  rdma

  For PCIe,
  cat /sys/class/nvme/nvme0/transport
  pcie

- address: This attributes shows the controller address. The fabrics
  drivers that will implement get_address can show the address of the
  connected controller.

  example:
  cat /sys/class/nvme/nvme0/address
  traddr=192.168.2.2,trsvcid=1023
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Reviewed-by: NJay Freyensee <james.p.freyensee@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

NVMe over fabrics will use __nvme_submit_sync_cmd in the the
transport and require a few tweaks to it.  For that we export it
and add a few more paramters:

1. allow passing a queue ID to the block layer

   For the NVMe over Fabrics connect command we need to able to specify a
   queue ID that we want to send the command on.  Add a qid parameter to
   the relevant functions to enable this behavior.

2. allow submitting at_head commands

   In cases where we want to (re)connect to a controller
   where we have inflight queued commands we want to first
   connect and only then allow the other queued commands to
   be kicked. This will prevents failures in controller resets
   and reconnects.

3. allow passing flags to blk_mq_allocate_request

   Both for Fabrics connect the the keep-alive feature in NVMe 1.2.1 we
   want to be able to use reserved requests.
Reviewed-by: NJay Freyensee <james.p.freyensee@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Tested-by: NMing Lin <ming.l@ssi.samsung.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

For Fabrics we're not going through an intermediate reset state
(at least for now).
Reviewed-by: NJay Freyensee <james.p.freyensee@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

We want to apply this to Fabrics drivers as well, so move it to common
code.
Reviewed-by: NJay Freyensee <james.p.freyensee@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Tested-by: NMing Lin <ming.l@ssi.samsung.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Centralize the check if a given NVMe command reads or writes data.
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJay Freyensee <james.p.freyensee@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Some transport drivers may have a lower transfer size than
the controller. So allow the transport to set it in the
controller max_hw_sectors.
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

In case of the active namespace list scanning method, a namespace that
is detached is not removed from the host if it was the last entry in
the list. Fix this by adding a scan to validate namespaces greater than
the value of prev.

This also handles the case of removing namespaces whose value exceed
the device's reported number of namespaces.
Signed-off-by: NSunad Bhandary S <sunad.s@samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

It's more elegant to use UINT_MAX to represent the max value of
type unsigned int. So replace the actual value by using this define.
Signed-off-by: NMinfei Huang <mnghuan@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

So it can be used by fabrics driver also.
Signed-off-by: NMing Lin <ming.l@samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NKeith Busch <keith.bsuch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

nvme_cancel_io is a bit confusing (given the distinction of io/admin),
so rename it to nvme_cancel_request.

And update it a bit to pass in struct nvme_ctrl, so it can be used
by Fabrics driver also.
Signed-off-by: NMing Lin <ming.l@samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Suggested-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NKeith Busch <keith.bsuch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.
Signed-off-by: NMike Christie <mchristi@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.
Signed-off-by: NMike Christie <mchristi@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

While doing recent bring-up of nvme/host with target-core T10-PI,
I noticed /sys/block/nvme*/integrity/device_is_integrity_capable
was false, and /sys/block/nvme*/integrity/tag_size contained
a bogus value.

AFAICT outside of blk_integrity_compare() for DM + MD these
are informational values, but go ahead and add the missing
assignments for nvme/host to match what SCSI does within
sd_dif_config_host() for consistency's sake.

Cc: Keith Busch <keith.busch@intel.com>
Cc: Jay Freyensee <james.p.freyensee@intel.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@grimberg.me>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Adds two Intel controllers that have the "stripe" quirk.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

This patch adds a new state that when set has the core automatically
kill request queues prior to removing namespaces.

If PCI device is not present at the time the nvme driver's remove is
called, we can kill all IO queues immediately instead of waiting for
the watchdog thread to do that at its polling interval. This improves
scenarios where multiple hot plug events occur at the same time since
it doesn't block the pci enumeration for as long.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

This exposes ioctl and sysfs methods a user can invoke to request the
driver rescan a controller and its namespaces. This is less harsh than
doing a controller reset, which temporarilly halts all IO, just to
surface a newly attached namespace.

This is mainly useful for controllers that implement the namespace
management command, but do not support the namespace notify change
asynchronous event notification.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Reduce error logging when no corrective action is required.
Suggessted-by: NChris Petersen <cpetersen@fb.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Instead of removing the PCI device from the kernel's topology on
controller failure, this patch simply requests unbinding the device
from the driver. This avoids concurrently running pci removal with the
hot plug event, which has been reported to be problematic when multiple
surprise events occur near simultaneously.

The other benefit is that we will have PCI config and memory space
available to poke around for debugging a failed controller, assuming
the device was not physically removed.

The down side occurs if the platform and/or kernel do not support any
type of surprise hot removal. The device will remain visible through
sysfs (and therefore lspci), and some manual work is necessary to get
the logical topology corrected. But if your platform and/or kernel don't
support surprise removal, you probably shouldn't be doing that anyway.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Use the online queue count instead of the number of allocated queues. The
controller should just return an invalid queue identifier error to the
commands if a queue wasn't created. While it's not harmful, it's still
not correct.
Reported-by: NSaar Gross <saar@annapurnalabs.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

The driver previously requested allocating queues for the total possible
number of CPUs so that blk-mq could rebalance these if CPUs were added
after initialization. The number of hardware contexts can now be changed
at runtime, so we only need to allocate the number of online queues
since we can add more later.
Suggested-by: NJeff Lien <jeff.lien@hgst.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

The number of ppas contained on a request is not necessarily the number
of pages that it maps to neither on the target nor on the device side.
In order to avoid confusion, rename nr_pages to nr_ppas since it is what
the variable actually contains.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

A recent change to lightnvm added code to pass a kernel pointer
to the hardware, which gcc complained about:

drivers/nvme/host/lightnvm.c: In function 'nvme_nvm_rqtocmd':
drivers/nvme/host/lightnvm.c:472:32: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
  c->ph_rw.metadata = cpu_to_le64(rqd->meta_list);

It looks like this has no way of working anyway, so this changes
the code to pass the dma_address instead. This was most likely
what was intended here. Neither of the two are currently ever
written to, so the effect is the same for now.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: a34b1eb78e21 ("lightnvm: enable metadata to be sent to device")
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Align with the rest of the nvme subsystem.
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Until now, the dma pool have been exclusively used to allocate the ppa
list being sent to the device. In pblk (upcoming), we use these pools to
allocate metadata too. Thus, we generalize the names of some variables
on the dma helper functions to make the code more readable.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Enable metadata buffer to be sent to the device through the metadata
field on the physical rw nvme command. The size of the metadata buffer
must follow dev->oob_size * # of PPAs.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Updated description.
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

The set_bb_tbl takes struct nvm_rq and only uses its ppa_list and
nr_pages internally. Instead, make these two variables explicit.
This allows a user to call it without initializing a struct nvm_rq
first.
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

The device ops->get_bb_tbl() takes a callback, that allows the caller
to use its own callback function to update its data structures in the
returning function.

This makes it difficult to send parameters to the callback, and usually
is circumvented by small private structures, that both carry the callers
state and any flags needed to fulfill the update.

Refactor ops->get_bb_tbl() to fill a data buffer with the status of the
blocks returned, and let the user call the callback function manually.
That will provide the necessary flags and data structures and simplify
the logic around ops->get_bb_tbl().
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

The get block table command returns a list of blocks and planes
with their associated state. Users, such as gennvm and sysblk,
manages all planes as a single virtual block.

It was therefore  natural to fold the bad block list before it is
returned. However, to allow users, which manages on a per-plane
block level, to also use the interface, the get_bb_tbl interface is
changed to not fold by default and instead let the caller fold if
necessary.

Reviewed by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

This fixes a scenario where device is present and being reset, but a
request to unbind the driver occurs.

A previous patch series addressing a device failure removal scenario
flushed reset_work after controller disable to unblock reset_work waiting
on a completion that wouldn't occur. This isn't safe as-is. The broken
scenario can potentially be induced with:

  modprobe nvme && modprobe -r nvme

To fix, the reset work is flushed immediately after setting the controller
removing flag, and any subsequent reset will not proceed with controller
initialization if the flag is set.

The controller status must be polled while active, so the watchdog timer
is also left active until the controller is disabled to cleanup requests
that may be stuck during namespace removal.

[Fixes: ff23a2a1]
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

On receipt of a namespace attribute changed AER, we acquire the
namespace mutex lock before proceeding to scan and validate the
namespace list. In case of namespace detach/delete command,
nvme_ns_remove function deadlocks trying to acquire the already held
lock.

All callers, except nvme_remove_namespaces(), of nvme_ns_remove()
already held namespaces_mutex. So we can simply fix the deadlock by
not acquiring the mutex in nvme_ns_remove() and acquiring it in
nvme_remove_namespaces().
Reported-by: NSunad Bhandary S <sunad.s@samsung.com>
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimerg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Switch to RCU freeing the namespace structure so that
nvme_start_queues, nvme_stop_queues and nvme_kill_queues would
be able to get away with only a RCU read side critical section.
Suggested-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimerg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

This hides command cleanup into nvme.h and fabrics drivers will
also use it.
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

The transport driver still needs to do the actual submission, but all the
higher level code can be shared.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NChristoph Hellwig <hch@lst.de>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

It's unused since "NVMe: Move error handling to failed reset handler".
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJon Derrick <jonathan.derrick@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

nvme_core_init does:
    1) register_blkdev
    2) __register_chrdev
    3) class_create

nvme_core_exit should do cleanup in the reverse order.
Signed-off-by: NWang Sheng-Hui <shhuiw@foxmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>