There is a problem when another module (e.g. nvmet) takes a reference on
the nvme block device and the physical nvme drive is removed.  In that
case nvme_free_ctrl() will not be called and the controller state will be
"deleting" or "dead" unless nvmet module releases the block device.
Later on, the same nvme drive probes back and nvme_init_subsystem() will
be called and fail due to duplicate subnqn (if the nvme device doesn't
support subsystem with multiple controllers). This will cause a probe
failure.  This commit changes the check of multiple controllers support
at nvme_init_subsystem() by not counting all the controllers at "dead" or
"deleting" state (this is safe because controllers at this state will
never be active again).

Fixes: ab9e00cc ("nvme: track subsystems")
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NIsrael Rukshin <israelr@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The block device is backed by the transport so we must ensure that the
transport driver will not be removed until all references are released.
Otherwise, we might end up referencing freed memory.
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NNitzan Carmi <nitzanc@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

When the io queues setup or tagset allocation failed, ctrl.tagset is
NULL.  But the scan work will still be queued and executed, then panic
comes up due to NULL pointer reference of ctrl.tagset.

To fix this, add a new ctrl state NVME_CTRL_ADMIN_ONLY to inidcate only
admin queue is live. When non io queues or tagset allocation failed, ctrl
enters into this state, scan work will not be started.  But async event
work and nvme dev ioctl will be still available.  This will be helpful to
do further investigation and recovery.
Suggested-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

When an NVMe controller reports RTD3 Entry Latency larger than the value
of shutdown_timeout module parameter, we update the shutdown_timeout
accordingly to honor RTD3 Entry Latency. Use an informational debug level
instead of a warning level for it.
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The ns->head is always valid, so we don't need to check for NULL.
Reported-by: NDan Carpenter <dan.caprenter@oracle.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This fixes using the NULL 'head' before getting the reference. It is
however possible the head will always be NULL, so this patch uses the
struct nvme_ns to get the ns_id field.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

"uuid" must be invisible if both ns->uuid and ns->nguid are unset,
not if either one is.

Fixes: d934f984 "nvme: provide UUID value to userspace"
Signed-off-by: NMartin Wilck <mwilck@suse.com>
[hch: rebased to the nvme-4.15 tree to help resolving a conflict]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We should be exposing the subsystem attributes like 'model' and
'subsysnqn' to sysfs to allow for easier identification of the
subsystem.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When creating nvme multipath devices we should populate the 'slaves' and
'holders' directorys properly to aid userspace topology detection.
Signed-off-by: NHannes Reinecke <hare@suse.com>
[hch: split from a larger patch, compile fix for CONFIG_NVME_MULTIPATH=n]
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We do this by adding a helper that returns the ns_head for a device that
can belong to either the per-controller or per-subsystem block device
nodes, and otherwise reuse all the existing code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch adds native multipath support to the nvme driver.  For each
namespace we create only single block device node, which can be used
to access that namespace through any of the controllers that refer to it.
The gendisk for each controllers path to the name space still exists
inside the kernel, but is hidden from userspace.  The character device
nodes are still available on a per-controller basis.  A new link from
the sysfs directory for the subsystem allows to find all controllers
for a given subsystem.

Currently we will always send I/O to the first available path, this will
be changed once the NVMe Asynchronous Namespace Access (ANA) TP is
ratified and implemented, at which point we will look at the ANA state
for each namespace.  Another possibility that was prototyped is to
use the path that is closes to the submitting NUMA code, which will be
mostly interesting for PCI, but might also be useful for RDMA or FC
transports in the future.  There is not plan to implement round robin
or I/O service time path selectors, as those are not scalable with
the performance rates provided by NVMe.

The multipath device will go away once all paths to it disappear,
any delay to keep it alive needs to be implemented at the controller
level.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Introduce a new struct nvme_ns_head that holds information about an actual
namespace, unlike struct nvme_ns, which only holds the per-controller
namespace information.  For private namespaces there is a 1:1 relation of
the two, but for shared namespaces this lets us discover all the paths to
it.  For now only the identifiers are moved to the new structure, but most
of the information in struct nvme_ns should eventually move over.

To allow lockless path lookup the list of nvme_ns structures per
nvme_ns_head is protected by SRCU, which requires freeing the nvme_ns
structure through call_srcu.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NJavier González <javier@cnexlabs.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This allows us to manage the various uniqueue namespace identifiers
together instead needing various variables and arguments.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This adds a new nvme_subsystem structure so that we can track multiple
controllers that belong to a single subsystem.  For now we only use it
to store the NQN, and to check that we don't have duplicate NQNs unless
the involved subsystems support multiple controllers.

Includes code originally from Hannes Reinecke to expose the subsystems
in sysfs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Several block layer and NVMe core functions accept a combination
of BLK_MQ_REQ_* flags through the 'flags' argument but there is
no verification at compile time whether the right type of block
layer flags is passed. Make it possible for sparse to verify this.
This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Tested-by: NOleksandr Natalenko <oleksandr@natalenko.name>
Cc: linux-nvme@lists.infradead.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This will give udev a chance to observe and handle asynchronous event
notifications and clear the log to unmask future events of the same type.
The driver will create a change uevent of the asyncronuos event result
before submitting the next AEN request to the device if a completed AEN
event is of type error, smart, command set or vendor specific,
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NGuan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Async event work is for core use only and should not be called directly
from drivers.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NGuan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The driver can handle tracking only one AEN request, so this patch
removes handling for multiple ones.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJames Smart  <james.smart@broadcom.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

All the transports were unnecessarilly duplicating the AEN request
accounting. This patch defines everything in one place.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NGuan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fix print formatting, but keep the original output to prevent user
breakage as suggested by Joe Perches.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Copy subnqns using NVMF_NQN_SIZE as it is < 256
Signed-off-by: NJavier González <javier@cnexlabs.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The NVMe standard provides a command effects log page so the host may
be aware of special requirements it may need to do for a particular
command. For example, the command may need to run with IO quiesced to
prevent timeouts or undefined behavior, or it may change the logical block
formats that determine how the host needs to construct future commands.

This patch saves the nvme command effects log page if the controller
supports it, and performs appropriate actions before and after an admin
passthrough command is completed. If the controller does not support the
command effects log page, the driver will define the effects for known
opcodes. The nvme format and santize are the only commands in this patch
with known effects.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

And fix the warning on a successful firmware log.
Reviewed-by: NJavier González <javier@cnexlabs.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Update the check in nvme_setup_rw for missing metadata so that it is
together with the other metadata handling, does not contain impossible
to reach conditions and warns if we get an impossible requests for
a (non-PI) metadata-enabled namespace when CONFIG_BLK_DEV_INTEGRITY
is not set.

Also add a little helper that checks if a given metadata configuration
contains protection information
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NJavier González <jg@lightnvm.io>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Split out the code that applies the calculate value to a given disk/queue
into new helper that can be reused by the multipath code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We don't need a frozen queue to update the chunk_size, which just is a
hint, and moving it a little earlier will allow for some better code
reuse with the multipath code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

To allow reusing this function for the multipath node.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

To allow reusing this function for the multipath node.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is safe because the queue is always frozen when we revalidate, and
it simplifies both the existing code as well as the multipath
implementation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

With multipath we don't want a hard DNR bit on a request that is cancelled
by a controller reset, but instead want to be able to retry it on another
patch.  To archive this don't always set the DNR bit when the queue is
dying in nvme_cancel_request, but defer that decision to
nvme_req_needs_retry.  Note that it applies to any command there and not
just cancelled commands, but one the queue is dying that is the right
thing to do anyway.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

a tiny typo fixed in a comment.
Signed-off-by: NMinwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Transport will typically transition from LIVE to RESETTING when initially
performing a reset or recovering from an error.  Adding this transition
allows a transport to transition to RECONNECTING when it checks/waits for
connectivity then creates new transport connections and reinits the
controller.
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Prevent racing controller reset and delete flows. reset_work must not
ever self-requeue so flushing it suffices.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

No change in behavior except that the FC code cancels two work items a
little later now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Move the ->delete_work and the associated helpers to common code instead
of duplicating them in every driver.  This also adds the missing reference
get/put for the loop driver.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Revalidating the disk needs to set the logical block format and capacity,
otherwise it can't figure out if the users modified anything about
the namespace.

Fixes: cdbff4f2 ("nvme: remove nvme_revalidate_ns")
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is a much more sensible check than just the admin queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@rimbeg.me>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>

Use the core chrdev code to set up the link between the character device
and the nvme controller.  This allows us to get rid of the global list
of all controllers, and also ensures that we have both a reference to
the controller and the transport module before the open method of the
character device is called.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sgi@grimberg.me>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>

Instead of allocating a separate struct device for the character device
handle embedd it into struct nvme_ctrl and use it for the main controller
refcounting.  This removes double refcounting and gets us an automatic
reference for the character device operations.  We keep ctrl->device as a
pointer for now to avoid chaning printks all over, but in the future we
could look into message printing helpers that take a controller structure
similar to what other subsystems do.

Note the delete_ctrl operation always already has a reference (either
through sysfs due this change, or because every open file on the
/dev/nvme-fabrics node has a refernece) when it is entered now, so we
don't need to do the unless_zero variant there.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>

Now that we are protected against lookup vs free races for the namespace
by using kref_get_unless_zero we don't need the hack of NULLing out the
disk private data during removal.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>