Move the special cases for fabrics commands and the discovery controller
to nvmet_parse_admin_cmd in preparation for adding passthrough support.
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Now that nvmet_req_execute does nothing, open code it.
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
[split patch, update changelog]
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Instead of storing the expected length and checking it when it's
executed, just check the length inside the command themselves.

A new helper, nvmet_check_data_len() is created to help with this
check.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
[split patch, udpate changelog]
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The call to sgl_alloc shouldn't fail so add this simple optimization to
the fast path.
Signed-off-by: NIsrael Rukshin <israelr@mellanox.com>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Presently, nvmet_file_flush() always returns a call to
errno_to_nvme_status() but that helper doesn't take into account the
case when errno=0. So nvmet_file_flush() always returns an error code.

All other callers of errno_to_nvme_status() check for success before
calling it.

To fix this, ensure errno_to_nvme_status() returns success if the
errno is zero. This should prevent future mistakes like this from
happening.

Fixes: c6aa3542 ("nvmet: add error log support for file backend")
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>

When a port is removed through configfs, any connected controllers
are still active and can still send commands. This causes a
use-after-free bug which is detected by KASAN for any admin command
that dereferences req->port (like in nvmet_execute_identify_ctrl).

To fix this, disconnect all active controllers when a subsystem is
removed from a port. This ensures there are no active controllers
when the port is eventually removed.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Reviewed-by : Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>

This patch introduces target-side request tracing.  As Christoph
suggested, the trace would not be in a core or module to avoid
disadvantages like cache miss:
  http://lists.infradead.org/pipermail/linux-nvme/2019-June/024721.html

The target-side trace code is entirely based on the Johannes's trace code
from the host side.  It has lots of codes duplicated, but it would be
better than having advantages mentioned above.

It also traces not only fabrics commands, but also nvme normal commands.
Once the codes to be shared gets bigger, then we can make it common as
suggsted.

This also removed the create_sq and create_cq trace parsing functions
because it will be done by the connect fabrics command.

Example:
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_init/enable
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_complete/enable
  cat /sys/kernel/debug/tracing/trace
Signed-off-by: NMinwoo Im <minwoo.im.dev@gmail.com>
[hch: fixed the symbol namespace and a an endianess conversion]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch introduces a nvme_is_fabrics() inline function to check
whether or not the given command structure is for fabrics.
Signed-off-by: NMinwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Some transports, such as FC-NVME, support discovery controller change
events without the use of a persistent discovery controller. FC receives
events via RSCN from the FC Fabric Controller or subsystem FC port.

This patch adds a nvmet transport op that is called whenever a
discovery change event occurs in the nvmet layer.

To facilitate the callback without adding another layer to cross into
core.c to reference the transport ops, the port structure snapshots
the transport ops when the port is enabled and clears them when disabled.
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NArun Easi <aeasi@marvell.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Build breaks:

    drivers/nvme/target/core.c: In function 'nvmet_req_alloc_sgl':
    drivers/nvme/target/core.c:939:12: error: implicit declaration of \
function 'sgl_alloc'; did you mean 'bio_alloc'? \
[-Werror=implicit-function-declaration]
      req->sg = sgl_alloc(req->transfer_len, GFP_KERNEL, &req->sg_cnt);
                ^~~~~~~~~
                bio_alloc
    drivers/nvme/target/core.c:939:10: warning: assignment makes pointer \
from integer without a cast [-Wint-conversion]
      req->sg = sgl_alloc(req->transfer_len, GFP_KERNEL, &req->sg_cnt);
              ^
    drivers/nvme/target/core.c: In function 'nvmet_req_free_sgl':
    drivers/nvme/target/core.c:952:3: error: implicit declaration of \
function 'sgl_free'; did you mean 'ida_free'? [-Werror=implicit-function-declaration]
       sgl_free(req->sg);
       ^~~~~~~~
       ida_free

Cause:

    1. missing include to <linux/scatterlist.h>
    2. SGL_ALLOC needs to be enabled

Therefore adding the missing include, as well as Kconfig dependency.
Signed-off-by: NEnrico Weigelt, metux IT consult <info@metux.net>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMinwoo Im <minwoo.im@samsung.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

nvmet_subsys_alloc() returns its pointer or NULL if it fails.  We can
see three different steps in this function:
  1. memory allocation
  2. argument check
  3. memory allocation for string

But now the callers of this function do not seem to handle case 2 by
returning -ENOMEM only even if it fails with an invalid parameter.

This patch specifies error codes so that caller can pass it to its own
caller.
Signed-off-by: NMinwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>.
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Use NVMe namings for improving code readability.
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Reviewed-by : Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

we need to make sure that subsystem lock is taken during ctrl's list
traversing. nvmet_ns_changed function is not static and can be used from
various callers simultaneously.
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

In case we create N namespaces while N < NVMET_MAX_NAMESPACES, we can
perform "echo 1 > <nsid>/enable" as much as we want. In case N ==
NVMET_MAX_NAMESPACES we fail. Make sure we have the same flow for any N.
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

In case we fail to enable p2pmem on the current namespace, disable the
backing store device before exiting.

Cc: Stephen Bates <sbates@raithlin.com>
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

After commit 4d43d395 (workqueue: Try to catch flush_work() without
INIT_WORK()), it can cause warning when delete nvme-loop device, trace
like:

[   76.601272] Call Trace:
[   76.601646]  ? del_timer+0x72/0xa0
[   76.602156]  __cancel_work_timer+0x1ae/0x270
[   76.602791]  cancel_work_sync+0x14/0x20
[   76.603407]  nvmet_ctrl_free+0x1b7/0x2f0 [nvmet]
[   76.604091]  ? free_percpu+0x168/0x300
[   76.604652]  nvmet_sq_destroy+0x106/0x240 [nvmet]
[   76.605346]  nvme_loop_destroy_admin_queue+0x30/0x60 [nvme_loop]
[   76.606220]  nvme_loop_shutdown_ctrl+0xc3/0xf0 [nvme_loop]
[   76.607026]  nvme_loop_delete_ctrl_host+0x19/0x30 [nvme_loop]
[   76.607871]  nvme_do_delete_ctrl+0x75/0xb0
[   76.608477]  nvme_sysfs_delete+0x7d/0xc0
[   76.609057]  dev_attr_store+0x24/0x40
[   76.609603]  sysfs_kf_write+0x4c/0x60
[   76.610144]  kernfs_fop_write+0x19a/0x260
[   76.610742]  __vfs_write+0x1c/0x60
[   76.611246]  vfs_write+0xfa/0x280
[   76.611739]  ksys_write+0x6e/0x120
[   76.612238]  __x64_sys_write+0x1e/0x30
[   76.612787]  do_syscall_64+0xbf/0x3a0
[   76.613329]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

We fix it by moving fatal_err_work init to nvmet_alloc_ctrl(), which may
more reasonable.
Signed-off-by: NYufen Yu <yuyufen@huawei.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Update license to use SPDX-License-Identifier instead of verbose license
text.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>

This patch defines a new macro NVMET_NO_ERROR_LOC to represent the
default error location value in the nvme-error-log-page.
This is a pure cleanup patch and it does not change any functionality.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Currently the u16 req->error_loc is being compared to -1 which
will always be false.  Fix this by casting -1 to u16 to fix this.

Detected by clang:
  warning: result of comparison of constant -1 with expression of
  type 'u16' (aka 'unsigned short') is always false
  [-Wtautological-constant-out-of-range-compare]

Fixes: 76574f37 ("nvmet: add interface to update error-log page")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds support for the file backend to populate the
error log entries. Here we map the errno to the NVMe status codes.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds the support to maintain error log page for the
nvmet-core.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds nvmet_req based interface to the nvmet-core so that
we can update the error log page. We update error log page in
the request completion path when status is not set to NVME_SC_SUCCESS.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds necessary fields in the target data structures to
support error log page. For a target controller, we add a new error log
field to maintain the error log, at any given point we maintain error
entries equal to NVMET_ERROR_LOG_SLOTS for each controller. In the
following patch, we also update the error log page entry in the I/O
completion path so we introduce a spinlock for synchronization of the
log.

For nvmet_req, we add a new field error_loc to hold the location of
the error in the command when the actual error occurs for each request
and a starting LBA if applicable.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch adds unlikely in the nvmet request completion path for the
status check in the low level function __nvmet_req_complete.
This is helpful in the scenario where host and target connection is
working smoothly.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Technical proposal 8005 "fabrics SQ flow control" introduces a mode
where a host and controller agree to omit sq_head pointer updates
when sending nvme completions.

In case the host indicated desire to operate in this mode (connect attribute)
the controller will return back a connect completion with sq_head value
of 0xffff as indication that it will omit sq_head pointer updates.

This mode saves us an atomic update in the I/O path.
Reviewed-by: NHannes Reinecke <hare@suse.com>
[hch: suggested better implementation]
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add functions to find connections requesting Discovery Change events
and send a notification to hosts that maintain an explicit persistent
connection and have and active Asynchronous Event Request pending.
Only Hosts that have access to the Subsystem effected by the change
will receive notifications of Discovery Change event.

Call these functions each time there is a configfs change that effects
the Discover Log Pages.

Set the OAES field in the Identify Controller response to advertise the
support for Asynchronous Event Notifications.
Signed-off-by: NJay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: NPhil Cayton <phil.cayton@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

It is perfectly valid that a host connects to a discovery subsystem
and gets an empty discovery log page since no subsystems are
provisioned to it. No reason to disallow connecting to the discovery
subsystem all together.
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NJay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: NPhil Cayton <phil.cayton@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Per change to specification allowing Discovery controllers to have
explicit persistent connections, remove restriction on Discovery
controllers allowing kato on connect.
Signed-off-by: NJay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Functions nvmet_aen_disabled and nvmet_clear_aen were using
values not bit numbers ie 1 << 9 not 9 for bit function clear_bit
and test_and_set_bit.
Signed-off-by: NJay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: NPhil Cayton <phil.cayton@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Move nvmet_aen_disabled and nvmet_clear_aen in preparation for other types
of controllers to use, initially the discovery controller.
Signed-off-by: NJay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

A controller that supports traffic based keep-alive can restart the keep
alive timer even when no keep-alive was not received in the kato period
as long as other admin or I/O commands were received.  For each command
set ctrl->cmd_seen to true, and when keep-alive timer expires, if any
commands were seen, resched ka_work instead of escalating to a fatal
error.
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Even without CONFIG_P2PDMA this results in a error print:
nvmet: no peer-to-peer memory is available that's supported by rxe0 and /dev/nullb0

Fixes: c6925093 ("nvmet: Optionally use PCI P2P memory")
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Create a configfs attribute in each nvme-fabrics namespace to enable P2P
memory use.  The attribute may be enabled (with a boolean) or a specific
P2P device may be given (with the device's PCI name).

When enabled, the namespace will ensure the underlying block device
supports P2P and is compatible with any specified P2P device.  If no device
was specified it will ensure there is compatible P2P memory somewhere in
the system.  Enabling a namespace with P2P memory will fail with EINVAL
(and an appropriate dmesg error) if any of these conditions are not met.

Once a controller is set up on a specific port, the P2P device to use for
each namespace will be found and stored in a radix tree by namespace ID.
When memory is allocated for a request, the tree is used to look up the P2P
device to allocate memory against.  If no device is in the tree (because no
appropriate device was found), or if allocation of P2P memory fails, fall
back to using regular memory.
Signed-off-by: NStephen Bates <sbates@raithlin.com>
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
[hch: partial rewrite of the initial code]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Add helpers to allocate and free the SGL in a struct nvmet_req:

  int nvmet_req_alloc_sgl(struct nvmet_req *req)
  void nvmet_req_free_sgl(struct nvmet_req *req)

This will be expanded in a future patch to implement peer-to-peer memory
DMAs and should be common with all target drivers.

The new helpers are used in nvmet-rdma.  Seeing we use req.transfer_len as
the length of the SGL it is set earlier and cleared on any error.  It also
seems to be unnecessary to accumulate the length as the map_sgl functions
should only ever be called once per request.
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NSagi Grimberg <sagi@grimberg.me>

strncmp() stops comparing when either the end of one of the first two arguments
is reached or when 'n' characters have been compared, whichever comes first.
That means that strncmp(s1, s2, n) is equivalent to strcmp(s1, s2) if n exceeds
the length of s1 or the length of s2. Since that is the case in
nvmet_find_get_subsys(), change strncmp() into strcmp(). This patch avoids that
the following warning is reported by smatch:

drivers/nvme/target/core.c:940:1 nvmet_find_get_subsys() error: strncmp() '"nqn.2014-08.org.nvmexpress.discovery"' too small (37 vs 223)
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch implements the Namespace Write Protect feature described in
"NVMe TP 4005a Namespace Write Protect". In this version, we implement
No Write Protect and Write Protect states for target ns which can be
toggled by set-features commands from the host side.

For write-protect state transition, we need to flush the ns specified
as a part of command so we also add helpers for carrying out synchronous
flush operations.
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: fixed an incorrect endianess conversion, minor cleanups]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Allow creating non-default ANA groups (group ID > 1).  Groups are created
either by assigning the group ID to a namespace, or by creating a configfs
group object under a specific port.  All namespaces assigned to a group
that doesn't have a configfs object for a given port are marked as
inaccessible.

Allow changing the ANA state on a per-port basis by creating an
ana_groups directory under each port, and another directory with an
ana_state file in it.  The default ANA group 1 directory is created
automatically for each port.

For all changes in ANA configuration the ANA change AEN is sent.  We only
keep a global changecount instead of additional per-group changecounts to
keep the implementation as simple as possible.
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>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>

Add support for Asynchronous Namespace Access as specified in NVMe 1.3
TP 4004.

Just add a default ANA group 1 that is optimized on all ports.  This is
(and will remain) the default assignment for any namespace not epxlicitly
assigned to another ANA group.  The ANA state can be manually changed
through the configfs interface, including the change state.

Includes fixes and improvements from Hannes Reinecke.
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>

TP 4004 introduces a new 'Maximum Number of Allocated Namespaces' field
in the Identify controller data to help the host size resources.  Put
an upper limit on the supported namespaces to be able to support this
value as supporting 32-bits worth of namespaces would lead to very
large buffers.  The limit is completely arbitrary at this point.
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>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>