nvme: split nvme_update_zone_info

nvme_update_zone_info does (admin queue) I/O to the device and can fail.
We fail to abort the queue limits update if that happen, but really
should avoid with the frozen I/O queue as much as possible anyway.

Split the logic into a helper to query the information that can be
called on an unfrozen queue and one to apply it to the queue limits.

Fixes: 9b130d681443 ("nvme: use the atomic queue limits update API")
Reported-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: use the atomic queue limits update API

Changes the callchains that update queue_limits to build an on-stack
queue_limits and update it atomically. Note that for now only the
admin queue actually passes it to the queue allocation function.
Doing the same for the gendisks used for the namespaces will require
a little more work.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: remove nvme_revalidate_zones

Handle setting the zone size / chunk_sectors and max_append_sectors
limits together with the other ZNS limits, and just open code the
call to blk_revalidate_zones in the current place.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: allow integrity when PI is not in first bytes

NVM command set 1.0 (or later) mandates PI to be in the last bytes of
metadata. But this was not supported in the block-layer, and driver
registered a nop profile.

Since block-integrity can now handle flexible PI offset, change the
driver to support this configuration.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240201130126.211402-4-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: move passthrough logging attribute to head

The namespace does not have attributes, but the head does. Move the new
logging attribute to that structure instead of dereferencing the wrong
type.

And while we're here, fix the reverse-tree coding style.

Fixes: 9f079dda14339e ("nvme: allow passthru cmd error logging")
Reported-by: Tasmiya Nalatwad <tasmiya@linux.vnet.ibm.com>
Tested-by: Tasmiya Nalatwad <tasmiya@linux.vnet.ibm.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Alan Adamson <alan.adamson@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: allow passthru cmd error logging

Commit d7ac8dca938c ("nvme: quiet user passthrough command errors")
disabled error logging for user passthrough commands. This commit
adds the ability to opt-in to passthrough admin error logging. IO
commands initiated as passthrough will always be logged.

The logging output for passthrough commands (Admin and IO) has been
changed to include CDWXX fields.

nvme0n1: Read(0x2), LBA Out of Range (sct 0x0 / sc 0x80) DNR cdw10=0x0 cdw11=0x1
cdw12=0x70000 cdw13=0x0 cdw14=0x0 cdw15=0x0

Add a helper function nvme_log_err_passthru() which allows us to log
error for passthru commands by decoding cdw10-cdw15 values of nvme
command.

Add a new sysfs attr passthru_err_log_enabled that allows user to conditionally
enable passthrough command logging for either passthrough Admin commands sent to
the controller or passthrough IO commands sent to a namespace.

By default, passthrough error logging is disabled.

To enable passthrough admin error logging:
echo 1 > /sys/class/nvme/nvme0/passthru_err_log_enabled

To disable passthrough admin error logging:
echo 0 > /sys/class/nvme/nvme0/passthru_err_log_enabled

To enable passthrough io error logging:
echo 1 > /sys/class/nvme/nvme0/nvme0n1/passthru_err_log_enabled

To disable passthrough io error logging:
echo 0 > /sys/class/nvme/nvme0/nvme0n1/passthru_err_log_enabled

Signed-off-by: Alan Adamson <alan.adamson@oracle.com>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: split out fabrics version of nvme_opcode_str()

nvme_opcode_str() currently supports admin, IO, and fabrics commands.
However, fabrics commands aren't allowed for the pci transport.
Currently the pci caller passes 0 as the fctype,
which means any fabrics command would be displayed as "Property Set".

Move fabrics command support into a function nvme_fabrics_opcode_str()
and remove the fctype argument to nvme_opcode_str().
This way, a fabrics command will display as "Unknown" for pci.
Convert the rdma and tcp transports to use nvme_fabrics_opcode_str().

Signed-off-by: Caleb Sander <csander@purestorage.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: return string as char *, not unsigned char *

The functions in drivers/nvme/host/constants.c returning human-readable
status and opcode strings currently use type "const unsigned char *".
Typically string constants use type "const char *",
so remove "unsigned" from the return types.
This is a purely cosmetic change to clarify that the functions
return text strings instead of an array of bytes, for example.

Signed-off-by: Caleb Sander <csander@purestorage.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: enable retries for authentication commands

Authentication commands might trigger a lengthy computation on the
controller or even a callout to an external entity.
In these cases the controller might return a status without the DNR
bit set, indicating that the command should be retried.
This patch enables retries for authentication commands by setting
NVME_SUBMIT_RETRY for __nvme_submit_sync_cmd().

Reported-by: Martin George <marting@netapp.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: change __nvme_submit_sync_cmd() calling conventions

Combine the two arguments 'flags' and 'at_head' from __nvme_submit_sync_cmd()
into a single 'flags' argument and use function-specific values to indicate
what should be set within the function.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: use ctrl state accessor

The ctrl->state value is updated in another thread using WRITE_ONCE, so
ensure all the readers use the appropriate accessor.

Reviewed-by: Sagi Grimberg <sagi@grmberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: introduce nvme_disk_is_ns_head helper

We currently rely on gendisk's file operations (fops) to distinguish
between a namespace head (ns_head) and a regular namespace. To enhance
code readability, introduce a helper function.
Additionally, we must ensure that the device is not an ns_head before
calling nvme_get_ns_from_dev(). To enforce this, add a WARN_ON check
within the nvme_get_ns_from_dev().

Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu Song <liusong@linux.alibaba.com>
[include fix: https://lore.kernel.org/oe-kbuild-all/202401031943.0N72Tkji-lkp@intel.com/]
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: simplify the max_discard_segments calculation

Just stash away the DMRL value in the nvme_ctrl struture, and leave
all interpretation to nvme_config_discard, where we know DSM is
supported by the time we're configuring the number of segments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: fix max_discard_sectors calculation

ctrl->max_discard_sectors stores a value that is potentially based of
the DMRSL field in Identify Controller, which is in units of LBAs and
thus dependent on the Format of a namespace.

Fix this by moving the calculation of max_discard_sectors entirely
into nvme_config_discard and replacing the ctrl->max_discard_sectors
value with a local variable so that the calculation is always
namespace-specific.

Fixes: 1a86924e4f46 ("nvme: fix interpretation of DMRSL")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: repack struct nvme_ns_head

ns_id, lba_shift and ms are always accessed for every read/write I/O in
nvme_setup_rw. By grouping these variables into one cacheline we can
safe some cycles.

4k sequential reads:

baseline patched
Bandwidth: 1620 1634
IOPs 66345579 66910939

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: add csi, ms and nuse to sysfs

libnvme is using the sysfs for enumarating the nvme resources. Though
there are few missing attritbutes in the sysfs. For these libnvme issues
commands during discovering.

As the kernel already knows all these attributes and we would like to
avoid libnvme to issue commands all the time, expose these missing
attributes.

The nuse value is updated on request because the nuse is a volatile
value. Since any user can read the sysfs attribute, a very simple rate
limit is added (update once every 5 seconds). A more sophisticated
update strategy can be added later if there is actually a need for it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: rename ns attribute group

Drop the 'id' part of the attribute group name because we want to expose
non 'id' related attributes via the ns attribute group.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: refactor ns info helpers

Pass in the nvme_ns_head pointer directly. This reduces the necessity on
the caller side have the nvme_ns data structure present. Thus we can
refactor the caller side in the next step as well.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: move ns id info to struct nvme_ns_head

Move the namesapce info to struct nvme_ns_head, because it's the same
for all associated namespaces.

Note: with multipathing enabled the PI information is shared between all
paths. If a path is using a different PI configuration it will overwrite
the previous settings. This is obviously not correct and such
configuration will be rejected in future. For the time being we expect
a correctly configured storage.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme-pci: Add sleep quirk for Kingston drives

Some Kingston NV1 and A2000 are wasting a lot of power on specific TUXEDO
platforms in s2idle sleep if 'Simple Suspend' is used.

This patch applies a new quirk 'Force No Simple Suspend' to achieve a
low power sleep without 'Simple Suspend'.

Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
Signed-off-by: Georg Gottleuber <ggo@tuxedocomputers.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: fix deadlock between reset and scan

If controller reset occurs when allocating namespace, both
nvme_reset_work and nvme_scan_work will hang, as shown below.

Test Scripts:

for ((t=1;t<=128;t++))
do
nsid=`nvme create-ns /dev/nvme1 -s 14537724 -c 14537724 -f 0 -m 0 \
-d 0 | awk -F: '{print($NF);}'`
nvme attach-ns /dev/nvme1 -n $nsid -c 0
done
nvme reset /dev/nvme1

We will find that both nvme_reset_work and nvme_scan_work hung:

INFO: task kworker/u249:4:17848 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
task:kworker/u249:4 state:D stack: 0 pid:17848 ppid: 2
flags:0x00000028
Workqueue: nvme-reset-wq nvme_reset_work [nvme]
Call trace:
__switch_to+0xb4/0xfc
__schedule+0x22c/0x670
schedule+0x4c/0xd0
blk_mq_freeze_queue_wait+0x84/0xc0
nvme_wait_freeze+0x40/0x64 [nvme_core]
nvme_reset_work+0x1c0/0x5cc [nvme]
process_one_work+0x1d8/0x4b0
worker_thread+0x230/0x440
kthread+0x114/0x120
INFO: task kworker/u249:3:22404 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
task:kworker/u249:3 state:D stack: 0 pid:22404 ppid: 2
flags:0x00000028
Workqueue: nvme-wq nvme_scan_work [nvme_core]
Call trace:
__switch_to+0xb4/0xfc
__schedule+0x22c/0x670
schedule+0x4c/0xd0
rwsem_down_write_slowpath+0x32c/0x98c
down_write+0x70/0x80
nvme_alloc_ns+0x1ac/0x38c [nvme_core]
nvme_validate_or_alloc_ns+0xbc/0x150 [nvme_core]
nvme_scan_ns_list+0xe8/0x2e4 [nvme_core]
nvme_scan_work+0x60/0x500 [nvme_core]
process_one_work+0x1d8/0x4b0
worker_thread+0x260/0x440
kthread+0x114/0x120
INFO: task nvme:28428 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
task:nvme state:D stack: 0 pid:28428 ppid: 27119
flags:0x00000000
Call trace:
__switch_to+0xb4/0xfc
__schedule+0x22c/0x670
schedule+0x4c/0xd0
schedule_timeout+0x160/0x194
do_wait_for_common+0xac/0x1d0
__wait_for_common+0x78/0x100
wait_for_completion+0x24/0x30
__flush_work.isra.0+0x74/0x90
flush_work+0x14/0x20
nvme_reset_ctrl_sync+0x50/0x74 [nvme_core]
nvme_dev_ioctl+0x1b0/0x250 [nvme_core]
__arm64_sys_ioctl+0xa8/0xf0
el0_svc_common+0x88/0x234
do_el0_svc+0x7c/0x90
el0_svc+0x1c/0x30
el0_sync_handler+0xa8/0xb0
el0_sync+0x148/0x180

The reason for the hang is that nvme_reset_work occurs while nvme_scan_work
is still running. nvme_scan_work may add new ns into ctrl->namespaces
list after nvme_reset_work frozen all ns->q in ctrl->namespaces list.
The newly added ns is not frozen, so nvme_wait_freeze will wait forever.
Unfortunately, ctrl->namespaces_rwsem is held by nvme_reset_work, so
nvme_scan_work will also wait forever. Now we are deadlocked!

PROCESS1 PROCESS2
============== ==============
nvme_scan_work
... nvme_reset_work
nvme_validate_or_alloc_ns nvme_dev_disable
nvme_alloc_ns nvme_start_freeze
down_write ...
nvme_ns_add_to_ctrl_list ...
up_write nvme_wait_freeze
... down_read
nvme_alloc_ns blk_mq_freeze_queue_wait
down_write

Fix by marking the ctrl with say NVME_CTRL_FROZEN flag set in
nvme_start_freeze and cleared in nvme_unfreeze. Then the scan can check
it before adding the new namespace (under the namespaces_rwsem).

Signed-off-by: Bitao Hu <yaoma@linux.alibaba.com>
Reviewed-by: Guixin Liu <kanie@linux.alibaba.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: introduce helper function to get ctrl state

The controller state is typically written by another CPU, so reading it
should ensure no optimizations are taken. This is a repeated pattern in
the driver, so start with adding a convenience function that returns the
controller state with READ_ONCE().

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: rework NVME_AUTH Kconfig selection

Having a single Kconfig symbol NVME_AUTH conflates the selection
of the authentication functions from nvme/common and nvme/host,
causing kbuild robot to complain when building the nvme target
only. So introduce a Kconfig symbol NVME_HOST_AUTH for the nvme
host bits and use NVME_AUTH for the common functions only.
And move the CRYPTO selection into nvme/common to make it
easier to read.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310120733.TlPOVeJm-lkp@intel.com/
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme-tcp: enable TLS handshake upcall

Add a fabrics option 'tls' and start the TLS handshake upcall
with the default PSK. When TLS is started the PSK key serial
number is displayed in the sysfs attribute 'tls_key'

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: improved uring polling

Drivers can poll requests directly, so use that. We just need to ensure
the driver's request was allocated from a polled hctx, so a special
driver flag is added to struct io_uring_cmd.

The allows unshared and multipath namespaces to use the same polling
callback, and multipath is guaranteed to get the same queue as the
command was submitted on. Previously multipath polling might check a
different path and poll the wrong info.

The other bonus is we don't need a bio payload in order to poll,
allowing commands like 'flush' and 'write zeroes' to be submitted on the
same high priority queue as read and write commands.

Finally, using the request based polling skips the unnecessary bio
overhead.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230612190343.2087040-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Print capabilities changes just once

This current dev_info() could be very verbose and being printed very
frequently depending on some userspace application sending some specific
commands.

Just print this message once and skip it until the controller resets.
Use a controller flag (NVME_CTRL_DIRTY_CAPABILITY) to track if the
capability needs a reset.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: Move pr code to it's own file

This patch moves the pr code to it's own file because I'm going to be
adding more functions and core.c is getting bigger.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230407200551.12660-10-michael.christie@oracle.com
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

nvme: skip optional id ctrl csi if it failed

A frequently recieved report is the driver requests the optional Command
Set Specific Identify Controller structure. Some controllers report this
in their error log, which tiggers other warnings to user space
monitoring the devices.

These error entries are harmless and of questionable value to save in
the log, but let's reduce their occurance by not resending the command
if it previously failed. This will not prevent the errors on the initial
module load, but will greatly reduce their occurance on any rescans and
resumes from suspend.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217445
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: move sysfs code to a dedicated sysfs.c file

The core.c file became long and hard to maintain. Create a dedicated
file to centralize the sysfs functionality. This is a common practice to
separate sysfs/configfs related logic from the main driver logic .c file.
For example, in the nvmet module the configfs interface has its own
dedicated file.

This patch does not include any functional changes.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
[merged dhchap memleak fixes, include nvme-auth.h]
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: reorder fields in 'struct nvme_ctrl'

Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct nvme_ctrl' from 5368 to 5344
bytes when all CONFIG_* are defined.

This structure is embedded into some other structures, so it helps reducing
their size as well.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

block: replace fmode_t with a block-specific type for block open flags

The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: check IO start time when deciding to defer KA

When a command completes, we set a flag which will skip sending a
keep alive at the next run of nvme_keep_alive_work when TBKAS is on.
However, if the command was submitted long ago, it's possible that
the controller may have also restarted its keep alive timer (as a
result of receiving the command) long ago. The following trace
demonstrates the issue, assuming TBKAS is on and KATO = 8 for
simplicity:

1. t = 0: submit I/O commands A, B, C, D, E
2. t = 0.5: commands A, B, C, D, E reach controller, restart its keep
alive timer
3. t = 1: A completes
4. t = 2: run nvme_keep_alive_work, see recent completion, do nothing
5. t = 3: B completes
6. t = 4: run nvme_keep_alive_work, see recent completion, do nothing
7. t = 5: C completes
8. t = 6: run nvme_keep_alive_work, see recent completion, do nothing
9. t = 7: D completes
10. t = 8: run nvme_keep_alive_work, see recent completion, do nothing
11. t = 9: E completes

At this point, 8.5 seconds have passed without restarting the
controller's keep alive timer, so the controller will detect a keep
alive timeout.

Fix this by checking the IO start time when deciding to defer sending a
keep alive command. Only set comp_seen if the command started after the
most recent run of nvme_keep_alive_work. With this change, the
completions of B, C, and D will not set comp_seen and the run of
nvme_keep_alive_work at t = 4 will send a keep alive.

Reported-by: Costa Sapuntzakis <costa@purestorage.com>
Reported-by: Randy Jennings <randyj@purestorage.com>
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: fix miss command type check

In the function nvme_passthru_end(), only the value of the command
opcode is checked, without checking the command type (IO command or
Admin command). When we send a Dataset Management command (The opcode
of the Dataset Management command is the same as the Set Feature
command), kernel thinks it is a set feature command, then sets the
controller's keep alive interval, and calls nvme_keep_alive_work().

Signed-off-by: min15.li <min15.li@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme-pci: add quirk for missing secondary temperature thresholds

On Kingston KC3000 and Kingston FURY Renegade (both have the same PCI
IDs) accessing temp3_{min,max} fails with an invalid field error (note
that there is no problem setting the thresholds for temp1).

This contradicts the NVM Express Base Specification 2.0b, page 292:

The over temperature threshold and under temperature threshold
features shall be implemented for all implemented temperature sensors
(i.e., all Temperature Sensor fields that report a non-zero value).

Define NVME_QUIRK_NO_SECONDARY_TEMP_THRESH that disables the thresholds
for all but the composite temperature and set it for this device.

Signed-off-by: Hristo Venev <hristo@venev.name>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add nvme_opcode_str function for all nvme cmd types

nvme_opcode_str will handle io/admin/fabrics ops

This improves NVMe errors logging

Signed-off-by: Amit Engel <Amit.Engel@dell.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove nvme_execute_passthru_rq

After moving the nvme_passthru_end call to the callers of
nvme_execute_passthru_rq, this function has become quite pointless,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: fix multipath crash caused by flush request when blktrace is enabled

The flush request initialized by blk_kick_flush has NULL bio,
and it may be dealt with nvme_end_req during io completion.
When blktrace is enabled, nvme_trace_bio_complete with multipath
activated trying to access NULL pointer bio from flush request
results in the following crash:

[ 2517.831677] BUG: kernel NULL pointer dereference, address: 000000000000001a
[ 2517.835213] #PF: supervisor read access in kernel mode
[ 2517.838724] #PF: error_code(0x0000) - not-present page
[ 2517.842222] PGD 7b2d51067 P4D 0
[ 2517.845684] Oops: 0000 [#1] SMP NOPTI
[ 2517.849125] CPU: 2 PID: 732 Comm: kworker/2:1H Kdump: loaded Tainted: G S 5.15.67-0.cl9.x86_64 #1
[ 2517.852723] Hardware name: XFUSION 2288H V6/BC13MBSBC, BIOS 1.13 07/27/2022
[ 2517.856358] Workqueue: nvme_tcp_wq nvme_tcp_io_work [nvme_tcp]
[ 2517.859993] RIP: 0010:blk_add_trace_bio_complete+0x6/0x30
[ 2517.863628] Code: 1f 44 00 00 48 8b 46 08 31 c9 ba 04 00 10 00 48 8b 80 50 03 00 00 48 8b 78 50 e9 e5 fe ff ff 0f 1f 44 00 00 41 54 49 89 f4 55 <0f> b6 7a 1a 48 89 d5 e8 3e 1c 2b 00 48 89 ee 4c 89 e7 5d 89 c1 ba
[ 2517.871269] RSP: 0018:ff7f6a008d9dbcd0 EFLAGS: 00010286
[ 2517.875081] RAX: ff3d5b4be00b1d50 RBX: 0000000002040002 RCX: ff3d5b0a270f2000
[ 2517.878966] RDX: 0000000000000000 RSI: ff3d5b0b021fb9f8 RDI: 0000000000000000
[ 2517.882849] RBP: ff3d5b0b96a6fa00 R08: 0000000000000001 R09: 0000000000000000
[ 2517.886718] R10: 000000000000000c R11: 000000000000000c R12: ff3d5b0b021fb9f8
[ 2517.890575] R13: 0000000002000000 R14: ff3d5b0b021fb1b0 R15: 0000000000000018
[ 2517.894434] FS: 0000000000000000(0000) GS:ff3d5b42bfc80000(0000) knlGS:0000000000000000
[ 2517.898299] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2517.902157] CR2: 000000000000001a CR3: 00000004f023e005 CR4: 0000000000771ee0
[ 2517.906053] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2517.909930] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2517.913761] PKRU: 55555554
[ 2517.917558] Call Trace:
[ 2517.921294] <TASK>
[ 2517.924982] nvme_complete_rq+0x1c3/0x1e0 [nvme_core]
[ 2517.928715] nvme_tcp_recv_pdu+0x4d7/0x540 [nvme_tcp]
[ 2517.932442] nvme_tcp_recv_skb+0x4f/0x240 [nvme_tcp]
[ 2517.936137] ? nvme_tcp_recv_pdu+0x540/0x540 [nvme_tcp]
[ 2517.939830] tcp_read_sock+0x9c/0x260
[ 2517.943486] nvme_tcp_try_recv+0x65/0xa0 [nvme_tcp]
[ 2517.947173] nvme_tcp_io_work+0x64/0x90 [nvme_tcp]
[ 2517.950834] process_one_work+0x1e8/0x390
[ 2517.954473] worker_thread+0x53/0x3c0
[ 2517.958069] ? process_one_work+0x390/0x390
[ 2517.961655] kthread+0x10c/0x130
[ 2517.965211] ? set_kthread_struct+0x40/0x40
[ 2517.968760] ret_from_fork+0x1f/0x30
[ 2517.972285] </TASK>

To avoid this situation, add a NULL check for req->bio before
calling trace_block_bio_complete.

Signed-off-by: Yanjun Zhang <zhangyanjun@cestc.cn>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: consolidate setting the tagset flags

All nvme transports should be using the same flags for their tagsets,
with the exception for the blocking flag that should only be set for
transports that can block in ->queue_rq.

Add a NVME_F_BLOCKING flag to nvme_ctrl_ops to control the blocking
behavior and lift setting the flags into nvme_alloc_{admin,io}_tag_set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set

Don't look at ctrl->ops as only RDMA and TCP actually support multiple
maps.

Fixes: 6dfba1c09c10 ("nvme-fc: use the tagset alloc/free helpers")
Fixes: ceee1953f923 ("nvme-loop: use the tagset alloc/free helpers")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl

Many of the callers decide which one to use based on a bool argument and
there is at least some code to be shared, so merge these two. Also
move a comment specific to a single callsite to that callsite.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hector Martin <marcan@marcan.st>

nvme-multipath: support io stats on the mpath device

Our mpath stack device is just a shim that selects a bottom namespace
and submits the bio to it without any fancy splitting. This also means
that we don't clone the bio or have any context to the bio beyond
submission. However it really sucks that we don't see the mpath device
io stats.

Given that the mpath device can't do that without adding some context
to it, we let the bottom device do it on its behalf (somewhat similar
to the approach taken in nvme_trace_bio_complete).

When the IO starts, we account the request for multipath IO stats using
REQ_NVME_MPATH_IO_STATS nvme_request flag to avoid queue io stats disable
in the middle of the request.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>

nvme: introduce nvme_start_request

In preparation for nvme-multipath IO stats accounting, we want the
accounting to happen in a centralized place. The request completion
is already centralized, but we need a common helper to request I/O
start.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>

nvme: rename the queue quiescing helpers

Naming the nvme helpers that wrap the block quiesce functionality
_start/_stop is rather confusing. Switch to using the quiesce naming
used by the block layer instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme-auth: convert dhchap_auth_list to an array

We know exactly how many dhchap contexts we will need, there is no need
to hold a list that we need to protect with a mutex. Convert to
a dynamically allocated array. And dhchap_context access state is
maintained by the chap itself.

Make dhchap_auth_mutex protect only the ctrl host_key and ctrl_key
in a fine-grained lock such that there is no long lasting acquisition
of the lock and no need to take/release this lock when flushing
authentication works.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-auth: no need to reset chap contexts on re-authentication

Now that the chap context is reset upon completion, this is no longer
needed. Also remove nvme_auth_reset as no callers are left.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-auth: guarantee dhchap buffers under memory pressure

We want to guarantee that we have chap buffers when a controller
reconnects under memory pressure. Add a mempool specifically
for that.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-auth: don't ignore key generation failures when initializing ctrl keys

nvme_auth_generate_key can fail, don't ignore it upon initialization.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: simplify transport specific device attribute handling

Allow the transport driver to override the attribute groups for the
control device, so that the PCIe driver doesn't manually have to add a
group after device creation and keep track of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested-by Gerd Bayer <gbayer@linxu.ibm.com>

nvme: move OPAL setup from PCIe to core

Nothing about the TCG Opal support is PCIe transport specific, so move it
to the core code. For this nvme_init_ctrl_finish grows a new
was_suspended argument that allows the transport driver to tell the OPAL
code if the controller came out of a suspend cycle.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Tested-by Gerd Bayer <gbayer@linxu.ibm.com>

nvme: implement the DEAC bit for the Write Zeroes command

While the specification allows devices to either deallocate data
or to actually write zeroes on any Write Zeroes command, many SSDs
only do the sensible thing and deallocate data when the DEAC bit
is specific. Set it when it is supported and the caller doesn't
explicitly opt out of deallocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

nvme: use blk_mq_[un]quiesce_tagset

All controller namespaces share the same tagset, so we can use this
interface which does the optimal operation for parallel quiesce based on
the tagset type(e.g. blocking tagsets and non-blocking tagsets).

nvme connect_q should not be quiesced when quiesce tagset, so set the
QUEUE_FLAG_SKIP_TAGSET_QUIESCE to skip it when init connect_q.

Currently we use NVME_NS_STOPPED to ensure pairing quiescing and
unquiescing. If use blk_mq_[un]quiesce_tagset, NVME_NS_STOPPED will be
invalided, so introduce NVME_CTRL_STOPPED to replace NVME_NS_STOPPED.
In addition, we never really quiesce a single namespace. It is a better
choice to move the flag from ns to ctrl.

Signed-off-by: Chao Leng <lengchao@huawei.com>
[hch: rebased on top of prep patches]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: split nvme_kill_queues

nvme_kill_queues does two things:

1) mark the gendisk of all namespaces dead
2) unquiesce all I/O queues

These used to be be intertwined due to block layer issues, but aren't
any more. So move the unquiscing of the I/O queues into the callers,
and rename the rest of the function to the now more descriptive
nvme_mark_namespaces_dead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove nvme_ctrl_init_connect_q

Unused now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: add common helpers to allocate and free tagsets

Add common helpers to allocate and tear down the admin and I/O tag sets,
including the special queues allocated with them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: send a rediscover uevent when a persistent discovery controller reconnects

When a discovery controller is disconnected, no AENs will arrive to
notify the host about discovery log change events.

In order to solve this, send a uevent notification when a
persistent discovery controller reconnects. We add a new ctrl
flag NVME_CTRL_STARTED_ONCE that will be set on the first
start, and consecutive calls will find it set, and send the
event to userspace if the controller is a discovery controller.

Upon the event reception, userspace will re-read the discovery
log page and will act upon changes as it sees fit.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: enumerate controller flags

We expect to grow a few of these flags for various purposes
so make them a proper enumeration.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: ensure subsystem reset is single threaded

The subsystem reset writes to a register, so we have to ensure the
device state is capable of handling that otherwise the driver may access
unmapped registers. Use the state machine to ensure the subsystem reset
doesn't try to write registers on a device already undergoing this type
of reset.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214771
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: handle effects after freeing the request

If a reset occurs after the scan work attempts to issue a command, the
reset may quisce the admin queue, which blocks the scan work's command
from dispatching. The scan work will not be able to complete while the
queue is quiesced.

Meanwhile, the reset work will cancel all outstanding admin tags and
wait until all requests have transitioned to idle, which includes the
passthrough request. But the passthrough request won't be set to idle
until after the scan_work flushes, so we're deadlocked.

Fix this by handling the end effects after the request has been freed.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216354
Reported-by: Jonathan Derrick <Jonathan.Derrick@solidigm.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

fs: add batch and poll flags to the uring_cmd_iopoll() handler

We need the poll_flags to know how to poll for the IO, and we should
have the batch structure in preparation for supporting batched
completions with iopoll.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: wire up async polling for io passthrough commands

Store a cookie during submission, and use that to implement
completion-polling inside the ->uring_cmd_iopoll handler.
This handler makes use of existing bio poll facility.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://lore.kernel.org/r/20220823161443.49436-5-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-pci: check DMA ops when indicating support for PCI P2PDMA

Introduce a supports_pci_p2pdma() operation in nvme_ctrl_ops to
replace the fixed NVME_F_PCI_P2PDMA flag such that the dma_map_ops
flags can be checked for PCI P2PDMA support.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-multipath: refactor nvme_mpath_add_disk

Pass anagrpid as second argument. This is prep patch that allows reusing
this function for supporting unknown command sets.

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: implement In-Band authentication

Implement NVMe-oF In-Band authentication according to NVMe TPAR 8006.
This patch adds two new fabric options 'dhchap_secret' to specify the
pre-shared key (in ASCII respresentation according to NVMe 2.0 section
8.13.5.8 'Secret representation') and 'dhchap_ctrl_secret' to specify
the pre-shared controller key for bi-directional authentication of both
the host and the controller.
Re-authentication can be triggered by writing the PSK into the new
controller sysfs attribute 'dhchap_secret' or 'dhchap_ctrl_secret'.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[axboe: fold in clang build fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove unused timeout parameter

The function __nvme_submit_sync_cmd() has following list of callers
that sets the timeout value to 0 :-

Callers | Timeout value
------------------------------------------------
nvme_submit_sync_cmd() | 0
nvme_features() | 0
nvme_sec_submit() | 0
nvmf_reg_read32() | 0
nvmf_reg_read64() | 0
nvmf_reg_write32() | 0
nvmf_connect_admin_queue() | 0
nvmf_connect_io_queue() | 0

Remove the timeout function parameter from __nvme_submit_sync_cmd() and
adjust the rest of code accordingly.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove a double word in a comment

Delete the redundant word 'be'.

Signed-off-by: Xiang wangx <wangxiang@cdjrlc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme/host: Use the enum req_op and blk_opf_t types

Improve static type checking by using the enum req_op type for variables
that represent a request operation and the new blk_opf_t type for
variables that represent request flags.

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-38-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: Drop 'reserved' arg of busy_tag_iter_fn

We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter
function so it may be dropped.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me> #nvme
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/1657109034-206040-6-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: fix regression when disconnect a recovering ctrl

We encountered a problem that the disconnect command hangs.
After analyzing the log and stack, we found that the triggering
process is as follows:
CPU0 CPU1
nvme_rdma_error_recovery_work
nvme_rdma_teardown_io_queues
nvme_do_delete_ctrl nvme_stop_queues
nvme_remove_namespaces
--clear ctrl->namespaces
nvme_start_queues
--no ns in ctrl->namespaces
nvme_ns_remove return(because ctrl is deleting)
blk_freeze_queue
blk_mq_freeze_queue_wait
--wait for ns to unquiesce to clean infligt IO, hang forever

This problem was not found in older kernels because we will flush
err work in nvme_stop_ctrl before nvme_remove_namespaces.It does not
seem to be modified for functional reasons, the patch can be revert
to solve the problem.

Revert commit 794a4cb3d2f7 ("nvme: remove the .stop_ctrl callout")

Signed-off-by: Ruozhu Li <liruozhu@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add bug report info for global duplicate id

The recent global id check is finding poorly implemented devices in the
wild. Include relavant device information in the output to help quicken
an appropriate quirk patch.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: enable uring-passthrough for admin commands

Add two new opcodes that userspace can use for admin commands:
NVME_URING_CMD_ADMIN : non-vectroed
NVME_URING_CMD_ADMIN_VEC : vectored variant

Wire up support when these are issued on controller node(/dev/nvmeX).

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220520090630.70394-3-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: fix interpretation of DMRSL

DMRSLl is in the unit of logical blocks, while max_discard_sectors is
in the unit of "linux sector".

Signed-off-by: Tom Yan <tom.ty89@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: wire-up uring-cmd support for io-passthru on char-device.

Introduce handler for fops->uring_cmd(), implementing async passthru
on char device (/dev/ngX). The handler supports newly introduced
operation NVME_URING_CMD_IO. This operates on a new structure
nvme_uring_cmd, which is similar to struct nvme_passthru_cmd64 but
without the embedded 8b result field. This field is not needed since
uring-cmd allows to return additional result via big-CQE.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220511054750.20432-5-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add a quirk to disable namespace identifiers

Add a quirk to disable using and exporting namespace identifiers for
controllers where they are broken beyond repair.

The most directly visible problem with non-unique namespace identifiers
is that they break the /dev/disk/by-id/ links, with the link for a
supposedly unique identifier now pointing to one of multiple possible
namespaces that share the same ID, and a somewhat random selection of
which one actually shows up.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme-multipath: fix hang when disk goes live over reconnect

nvme_mpath_init_identify() invoked from nvme_init_identify() fetches a
fresh ANA log from the ctrl. This is essential to have an up to date
path states for both existing namespaces and for those scan_work may
discover once the ctrl is up.

This happens in the following cases:
1) A new ctrl is being connected.
2) An existing ctrl is successfully reconnected.
3) An existing ctrl is being reset.

While in (1) ctrl->namespaces is empty, (2 & 3) may have namespaces, and
nvme_read_ana_log() may call nvme_update_ns_ana_state().

This result in a hang when the ANA state of an existing namespace changes
and makes the disk live: nvme_mpath_set_live() issues IO to the namespace
through the ctrl, which does NOT have IO queues yet.

See sample hang below.

Solution:
- nvme_update_ns_ana_state() to call set_live only if ctrl is live
- nvme_read_ana_log() call from nvme_mpath_init_identify()
therefore only fetches and parses the ANA log;
any erros in this process will fail the ctrl setup as appropriate;
- a separate function nvme_mpath_update()
is called in nvme_start_ctrl();
this parses the ANA log without fetching it.
At this point the ctrl is live,
therefore, disks can be set live normally.

Sample failure:
nvme nvme0: starting error recovery
nvme nvme0: Reconnecting in 10 seconds...
block nvme0n6: no usable path - requeuing I/O
INFO: task kworker/u8:3:312 blocked for more than 122 seconds.
Tainted: G E 5.14.5-1.el7.elrepo.x86_64 #1
Workqueue: nvme-wq nvme_tcp_reconnect_ctrl_work [nvme_tcp]
Call Trace:
__schedule+0x2a2/0x7e0
schedule+0x4e/0xb0
io_schedule+0x16/0x40
wait_on_page_bit_common+0x15c/0x3e0
do_read_cache_page+0x1e0/0x410
read_cache_page+0x12/0x20
read_part_sector+0x46/0x100
read_lba+0x121/0x240
efi_partition+0x1d2/0x6a0
bdev_disk_changed.part.0+0x1df/0x430
bdev_disk_changed+0x18/0x20
blkdev_get_whole+0x77/0xe0
blkdev_get_by_dev+0xd2/0x3a0
__device_add_disk+0x1ed/0x310
device_add_disk+0x13/0x20
nvme_mpath_set_live+0x138/0x1b0 [nvme_core]
nvme_update_ns_ana_state+0x2b/0x30 [nvme_core]
nvme_update_ana_state+0xca/0xe0 [nvme_core]
nvme_parse_ana_log+0xac/0x170 [nvme_core]
nvme_read_ana_log+0x7d/0xe0 [nvme_core]
nvme_mpath_init_identify+0x105/0x150 [nvme_core]
nvme_init_identify+0x2df/0x4d0 [nvme_core]
nvme_init_ctrl_finish+0x8d/0x3b0 [nvme_core]
nvme_tcp_setup_ctrl+0x337/0x390 [nvme_tcp]
nvme_tcp_reconnect_ctrl_work+0x24/0x40 [nvme_tcp]
process_one_work+0x1bd/0x360
worker_thread+0x50/0x3d0

Signed-off-by: Anton Eidelman <anton@lightbitslabs.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: allow duplicate NSIDs for private namespaces

A NVMe subsystem with multiple controller can have private namespaces
that use the same NSID under some conditions:

"If Namespace Management, ANA Reporting, or NVM Sets are supported, the
NSIDs shall be unique within the NVM subsystem. If the Namespace
Management, ANA Reporting, and NVM Sets are not supported, then NSIDs:
a) for shared namespace shall be unique; and
b) for private namespace are not required to be unique."

Reference: Section 6.1.6 NSID and Namespace Usage; NVM Express 1.4c spec.

Make sure this specific setup is supported in Linux.

Fixes: 9ad1927a3bc2 ("nvme: always search for namespace head")
Signed-off-by: Sungup Moon <sungup.moon@samsung.com>
[hch: refactored and fixed the controller vs subsystem based naming
conflict]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: add support for enhanced metadata

NVM Express ratified TP 4068 defines new protection information formats.
Implement support for the CRC64 guard tags.

Since the block layer doesn't support variable length reference tags,
driver support for the Storage Tag space is not supported at this time.

Cc: Hannes Reinecke <hare@suse.de>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Klaus Jensen <its@irrelevant.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220303201312.3255347-9-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove support or stream based temperature hint

This support was added for RocksDB, but RocksDB ended up not using it.
At the same time drives on the open marked (vs those build for OEMs
for non-Linux support) that actually support streams are extremly
rare. Don't bloat the nvme driver for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220304175556.407719-1-hch@lst.de
[axboe: fold in ctrl->nr_streams removal from Keith]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove nvme_alloc_request and nvme_alloc_request_qid

Just open code the allocation + initialization in the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: cleanup how disk->disk_name is assigned

They way how assigning the disk name and commenting on why it is done
is split over core.c and multipath.c seems to be rather confusing.

Now that ns_head->disk always exists we can do all the work in core.c
and have a single big comment explaining the issues.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme: remove nssa from struct nvme_ctrl

The reported number of streams is not used outside the function that
gets it, so no need to stash it in the controller structure. Use a local
variable instead.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: expose cntrltype and dctype through sysfs

TP8010 introduces the Discovery Controller Type attribute (dctype).
The dctype is returned in the response to the Identify command. This
patch exposes the dctype through the sysfs. Since the dctype depends on
the Controller Type (cntrltype), another attribute of the Identify
response, the patch also exposes the cntrltype as well. The dctype will
only be displayed for discovery controllers.

A note about the naming of this attribute:
Although TP8010 calls this attribute the Discovery Controller Type,
note that the dctype is now part of the response to the Identify
command for all controller types. I/O, Discovery, and Admin controllers
all share the same Identify response PDU structure. Non-discovery
controllers as well as pre-TP8010 discovery controllers will continue
to set this field to 0 (which has always been the default for reserved
bytes). Per TP8010, the value 0 now means "Discovery controller type is
not reported" instead of "Reserved". One could argue that this
definition is correct even for non-discovery controllers, and by
extension, exposing it in the sysfs for non-discovery controllers is
appropriate.

Signed-off-by: Martin Belanger <martin.belanger@dell.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add verbose error logging

Improves logging of NVMe errors. If NVME_VERBOSE_ERRORS is configured,
a verbose description of the error is logged, otherwise only status
codes/bits is logged.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
[kch]: fix several nits, cosmetics, and trim down code.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Alan Adamson <alan.adamson@oracle.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add a helper to initialize connect_q

Add and use helper to remove duplicate code for fabrics connect_q
initialization and error handling for all the transports.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add 'iopolicy' module parameter

While the 'iopolicy' sysfs attribute can be set at runtime, most
storage arrays prefer to use the 'round-robin' iopolicy per default.
We can use udev rules to set this, but is getting rather unwieldy
for rebranded arrays as we would have to update the udev rules
anytime a new array shows up, leading to the same mess we currently
have in multipathd for configuring the RDAC arrays.

Hence this patch adds a module parameter 'iopolicy' to allow the
admin to switch the default, and to do away with the need for a
udev rule here.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: increment request genctr on completion

The nvme request generation counter is intended to catch duplicate
completions. Incrementing the counter on submission means duplicates can
only be caught if the request tag is reallocated and dispatched prior to
the driver observing the corrupted CQE. Incrementing on completion
removes this window, making it possible to detect duplicate completions
in consecutive entries.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: fix use after free when disconnecting a reconnecting ctrl

A crash happens when trying to disconnect a reconnecting ctrl:

1) The network was cut off when the connection was just established,
scan work hang there waiting for some IOs complete. Those I/Os were
retried because we return BLK_STS_RESOURCE to blk in reconnecting.
2) After a while, I tried to disconnect this connection. This
procedure also hangs because it tried to obtain ctrl->scan_lock.
It should be noted that now we have switched the controller state
to NVME_CTRL_DELETING.
3) In nvme_check_ready(), we always return true when ctrl->state is
NVME_CTRL_DELETING, so those retrying I/Os were issued to the bottom
device which was already freed.

To fix this, when ctrl->state is NVME_CTRL_DELETING, issue cmd to bottom
device only when queue state is live. If not, return host path error to
the block layer

Signed-off-by: Ruozhu Li <liruozhu@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: expose subsystem type in sysfs attribute 'subsystype'

With unique discovery controller NQNs we cannot distinguish the
subsystem type by the NQN alone, but need to check the subsystem
type, too.
So expose the subsystem type in a new sysfs attribute 'subsystype'.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: paring quiesce/unquiesce

The current blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() always
stops and starts the queue unconditionally. And there can be concurrent
quiesce/unquiesce coming from different unrelated code paths, so
unquiesce may come unexpectedly and start queue too early.

Prepare for supporting concurrent quiesce/unquiesce from multiple
contexts, so that we can address the above issue.

NVMe has very complicated quiesce/unquiesce use pattern, add one atomic
bit for makeiing sure that blk-mq quiece/unquiesce is always called in
pair.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add APIs for stopping/starting admin queue

Add two APIs for stopping and starting admin queue.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014081710.1871747-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add support for batched completion of polled IO

Take advantage of struct io_comp_batch, if passed in to the nvme poll
handler. If it's set, rather than complete each request individually
inline, store them in the io_comp_batch list. We only do so for requests
that will complete successfully, anything else will be completed inline as
before.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add command id quirk for apple controllers

Some apple controllers use the command id as an index to implementation
specific data structures and will fail if the value is out of bounds.
The nvme driver's recently introduced command sequence number breaks
this controller.

Provide a quirk so these spec incompliant controllers can function as
before. The driver will not have the ability to detect bad completions
when this quirk is used, but we weren't previously checking this anyway.

The quirk bit was selected so that it can readily apply to stable.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214509
Cc: Sven Peter <sven@svenpeter.dev>
Reported-by: Orlando Chamberlain <redecorating@protonmail.com>
Reported-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Sven Peter <sven@svenpeter.dev>
Link: https://lore.kernel.org/r/20210927154306.387437-1-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: move nvme_multi_css into nvme.h

Preparatory patch in order to reuse nvme_multi_css in the nvme target
code.

Signed-off-by: Adam Manzanares <a.manzanares@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-multipath: revalidate paths during rescan

When triggering a rescan due to a namespace resize we will be
receiving AENs on every controller, triggering a rescan of all
attached namespaces. If multipath is active only the current path and
the ns_head disk will be updated, the other paths will still refer to
the old size until AENs for the remaining controllers are received.

If I/O comes in before that it might be routed to one of the old
paths, triggering an I/O failure with 'access beyond end of device'.
With this patch the old paths are skipped from multipath path
selection until the controller serving these paths has been rescanned.

Signed-off-by: Hannes Reinecke <hare@suse.de>
[dwagner: - introduce NVME_NS_READY flag instead of NVME_NS_INVALIDATE
- use 'revalidate' instead of 'invalidate' which
follows the zoned device code path.
- clear NVME_NS_READY before clearing current_path]
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove the unused NVME_NS_* enum

These values are unused now that the lightnvm support is gone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>

nvme: remove nvm_ndev from ns

Now that the lightnvm driver is removed, we don't need a pointer to it's
now non-existent struct.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: code command_id with a genctr for use-after-free validation

We cannot detect a (perhaps buggy) controller that is sending us
a completion for a request that was already completed (for example
sending a completion twice), this phenomenon was seen in the wild
a few times.

So to protect against this, we use the upper 4 msbits of the nvme sqe
command_id to use as a 4-bit generation counter and verify it matches
the existing request generation that is incrementing on every execution.

The 16-bit command_id structure now is constructed by:
| xxxx | xxxxxxxxxxxx |
gen request tag

This means that we are giving up some possible queue depth as 12 bits
allow for a maximum queue depth of 4095 instead of 65536, however we
never create such long queues anyways so no real harm done.

Suggested-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Tested-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

remove the lightnvm subsystem

Lightnvm supports the OCSSD 1.x and 2.0 specs which were early attempts
to produce Open Channel SSDs and never made it into the NVMe spec
proper. They have since been superceeded by NVMe enhancements such
as ZNS support. Remove the support per the deprecation schedule.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210812132308.38486-1-hch@lst.de
Reviewed-by: Matias Bjørling <mb@lightnvm.io>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: fix refcounting imbalance when all paths are down

When the last path to a ns_head drops the current code
removes the ns_head from the subsystem list, but will only
delete the disk itself if the last reference to the ns_head
drops. This is causing an refcounting imbalance eg when
applications have a reference to the disk, as then they'll
never get notified that the disk is in fact dead.
This patch moves the call 'del_gendisk' into nvme_mpath_check_last_path(),
ensuring that the disk can be properly removed and applications get the
appropriate notifications.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: use return value from blk_execute_rq()

We don't have an nvme status to report if the driver's .queue_rq()
returns an error without dispatching the requested nvme command. Check
the return value from blk_execute_rq() for all passthrough commands so
the caller may know their command was not successful.

If the command is from the target passthrough interface and fails to
dispatch, synthesize the response back to the host as a internal target
error.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210610214437.641245-5-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: use blk_execute_rq() for passthrough commands

The generic blk_execute_rq() knows how to handle polled completions. Use
that instead of implementing an nvme specific handler.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210610214437.641245-3-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add a helper to check ctrl sgl support

For various transports such as fc/tcp/pci it is common to check if
NVMe SGLs are supported or not by the controller.

In this preparation patch we add a helper to avoid the open coding of
such checks in the various transport.

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

nvme: remove nvme_{get,put}_ns_from_disk

Now that only one caller is left remove the helpers by restructuring
nvme_pr_command so that it has two helpers for sending a command of to a
given nsid using either the ns_head for multipath, or the namespace
stored in the gendisk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: split nvme_report_zones

Split multipath support out of nvme_report_zones into a separate helper
and simplify the non-multipath version as a result.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme-multipath: fix double initialization of ANA state

nvme_init_identify and thus nvme_mpath_init can be called multiple
times and thus must not overwrite potentially initialized or in-use
fields. Split out a helper for the basic initialization when the
controller is initialized and make sure the init_identify path does
not blindly change in-use data structures.

Fixes: 0d0b660f214d ("nvme: add ANA support")
Reported-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>

nvme: move the fabrics queue ready check routines to core

queue_rq() in pci only checks if the dispatched queue (nvmeq) is ready,
e.g. not being suspended. Since nvme_alloc_admin_tags() in reset flow
restarts the admin queue, users are able to submit admin commands to a
controller before reset_work() completes. Commands submitted under this
condition may interfere with commands that performs identify, IO queue
setup in reset_work(), and may result in a hang described in the
following patch.

As seen in the fabrics, user commands are prevented from being executed
under inproper controller states. We may reuse this logic to maintain a
clear admin queue during reset_work().

Signed-off-by: Tao Chiu <taochiu@synology.com>
Signed-off-by: Cody Wong <codywong@synology.com>
Reviewed-by: Leon Chien <leonchien@synology.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: fix controller ioctl through ns_head

In multipath case, we should consider namespace attachment with
controllers in a subsystem when we find out the live controller for the
namespace. This patch manually reverted the commit 3557a4409701
("nvme: don't bother to look up a namespace for controller ioctls") with
few more updates to nvme_ns_head_chr_ioctl which has been newly updated.

Fixes: 3557a4409701 ("nvme: don't bother to look up a namespace for
controller ioctls")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce generic per-namespace chardev

Userspace has not been allowed to I/O to device that's failed to
be initialized. This patch introduces generic per-namespace character
device to allow userspace to I/O regardless the block device is there or
not.

The chardev naming convention will similar to the existing blkdev naming,
using a ng prefix instead of nvme, i.e.

- /dev/ngXnY

It also supports multipath which means it will not expose chardev for the
hidden namespace blkdevs (e.g., nvmeXcYnZ). If /dev/ngXnY is created for
a ns_head, then I/O request will be routed to a specific controller
selected by the iopolicy of the subsystem.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Tested-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: sanitize KATO setting

According to the NVMe base spec the KATO commands should be sent
at half of the KATO interval, to properly account for round-trip
times.
As we now will only ever send one KATO command per connection we
can easily use the recommended values.
This also fixes a potential issue where the request timeout for
the KATO command does not match the value in the connect command,
which might be causing spurious connection drops from the target.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: move nvme_ns_head_ops to multipath.c

Move the multipath block_device_operations to multipath.c, where they
belong.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

nvme: move the ioctl code to a separate file

Split out the ioctl code from core.c into a new file. Also update
copyrights while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

nvme: pass a user pointer to nvme_nvm_ioctl

Pass the proper user pointer instead of the not all that useful integer
representation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Javier González <javier.gonz@samsung.com>

nvme: cleanup setting the disk name

Return false from nvme_set_disk_name and let the caller set the
non-multipath name instead of duplicating the naming information in two
places. Also remove the pointless local variables for the disk name
and flags and the not needed ctrl argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Javier González <javier.gonz@samsung.com>

nvme: add a nvme_ns_head_multipath helper

Move the multipath gendisk out of #ifdef CONFIG_NVME_MULTIPATH and add
a new nvme_ns_head_multipath that uses it to check if a ns_head has
a multipath device associated with it.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
[hch: added the IS_ENABLED, converted a few existing users]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

nvme: implement non-mdts command limits

Commands that access LBA contents without a data transfer between the
host historically have not had a spec defined upper limit. The driver
set the queue constraints for such commands to the max data transfer
size just to be safe, but this artificial constraint frequently limits
devices below their capabilities.

The NVMe Workgroup ratified TP4040 defines how a controller may
advertise their non-MDTS limits. Use these if provided and default to
the current constraints if not. Since the Dataset Management command
limits are defined in logical blocks, but without a namespace to tell us
the logical block size, the code defaults to the safe 512b size.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: use driver pdu command for passthrough

All nvme transport drivers preallocate an nvme command for each request.
Assume to use that command for nvme_setup_cmd() instead of requiring
drivers pass a pointer to it. All nvme drivers must initialize the
generic nvme_request 'cmd' to point to the transport's preallocated
nvme_command.

The generic nvme_request cmd pointer had previously been used only as a
temporary copy for passthrough commands. Since it now points to the
command that gets dispatched, passthrough commands must directly set it
up prior to executing the request.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: rename nvme_init_identify()

This is a prep patch so that we can move the identify data structure
related code initialization from nvme_init_identify() into a helper.

Rename the function nvmet_init_identify() to nvmet_init_ctrl_finish().

Next patch will move the nvme_id_ctrl related initialization from newly
renamed function nvme_init_ctrl_finish() into the nvme_init_identify()
helper.

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

nvme: use NVME_CTRL_CMIC_ANA macro

Use the proper macro instead of hard-coded value.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add 48-bit DMA address quirk for Amazon NVMe controllers

Some Amazon NVMe controllers do not follow the NVMe specification
and are limited to 48-bit DMA addresses. Add a quirk to force
bounce buffering if needed and limit the IOVA allocation for these
devices.

This affects all current Amazon NVMe controllers that expose EBS
volumes (0x0061, 0x0065, 0x8061) and local instance storage
(0xcd00, 0xcd01, 0xcd02).

Signed-off-by: Filippo Sironi <sironi@amazon.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-hwmon: rework to avoid devm allocation

The original design to use device-managed resource allocation
doesn't really work as the NVMe controller has a vastly different
lifetime than the hwmon sysfs attributes, causing warning about
duplicate sysfs entries upon reconnection.
This patch reworks the hwmon allocation to avoid device-managed
resource allocation, and uses the NVMe controller as parent for
the sysfs attributes.

Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Tested-by: Enzo Matsumiya <ematsumiya@suse.de>
Tested-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce a nvme_host_path_error helper

When using nvme native multipathing, if a path related error occurs
during ->queue_rq, the request needs to be completed with
NVME_SC_HOST_PATH_ERROR so that the request can be failed over.

Introduce a helper to complete the command from ->queue_rq in a wait
that invokes nvme_complete_rq.

Signed-off-by: Chao Leng <lengchao@huawei.com>
[hch: renamed, added a return value to clean up the callers a bit]
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-core: add cancel tagset helpers

Add nvme_cancel_tagset and nvme_cancel_admin_tagset for tear down and
reconnection error handling.

Signed-off-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove the unused status argument from nvme_trace_bio_complete

The only used argument in this function is the "req".

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: unexport functions with no external caller

There are no callers for nvme_reset_ctrl_sync() and
nvme_alloc_request_qid() so that we keep the symbols exported.

Unexport those functions, mark them static and update the header file
respectively.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: export zoned namespaces without Zone Append support read-only

Allow ZNS NVMe SSDs to present a read-only namespace when append is not
supported, instead of rejecting the namespace directly.

This allows (i) the namespace to be used in read-only mode, which is not
a problem as the append command only affects the write path, and (ii) to
use standard management tools such as nvme-cli to choose a different
format or firmware slot that is compatible with the Linux zoned block
device.

Signed-off-by: Javier González <javier.gonz@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-fabrics: reject I/O to offline device

Commands get stuck while Host NVMe-oF controller is in reconnect state.
The controller enters into reconnect state when it loses connection with
the target. It tries to reconnect every 10 seconds (default) until
a successful reconnect or until the reconnect time-out is reached.
The default reconnect time out is 10 minutes.

Applications are expecting commands to complete with success or error
within a certain timeout (30 seconds by default). The NVMe host is
enforcing that timeout while it is connected, but during reconnect the
timeout is not enforced and commands may get stuck for a long period or
even forever.

To fix this long delay due to the default timeout, introduce new
"fast_io_fail_tmo" session parameter. The timeout is measured in seconds
from the controller reconnect and any command beyond that timeout is
rejected. The new parameter value may be passed during 'connect'.
The default value of -1 means no timeout (similar to current behavior).

Signed-off-by: Victor Gladkov <victor.gladkov@kioxia.com>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: split nvme_alloc_request()

Right now nvme_alloc_request() allocates a request from block layer
based on the value of the qid. When qid set to NVME_QID_ANY it used
blk_mq_alloc_request() else blk_mq_alloc_request_hctx().

The function nvme_alloc_request() is called from different context, The
only place where it uses non NVME_QID_ANY value is for fabrics connect
commands :-

nvme_submit_sync_cmd() NVME_QID_ANY
nvme_features() NVME_QID_ANY
nvme_sec_submit() NVME_QID_ANY
nvmf_reg_read32() NVME_QID_ANY
nvmf_reg_read64() NVME_QID_ANY
nvmf_reg_write32() NVME_QID_ANY
nvmf_connect_admin_queue() NVME_QID_ANY
nvme_submit_user_cmd() NVME_QID_ANY
nvme_alloc_request()
nvme_keep_alive() NVME_QID_ANY
nvme_alloc_request()
nvme_timeout() NVME_QID_ANY
nvme_alloc_request()
nvme_delete_queue() NVME_QID_ANY
nvme_alloc_request()
nvmet_passthru_execute_cmd() NVME_QID_ANY
nvme_alloc_request()
nvmf_connect_io_queue() QID
__nvme_submit_sync_cmd()
nvme_alloc_request()

With passthru nvme_alloc_request() now falls into the I/O fast path such
that blk_mq_alloc_request_hctx() is never gets called and that adds
additional branch check in fast path.

Split the nvme_alloc_request() into nvme_alloc_request() and
nvme_alloc_request_qid().

Replace each call of the nvme_alloc_request() with NVME_QID_ANY param
with a call to newly added nvme_alloc_request() without NVME_QID_ANY.

Replace a call to nvme_alloc_request() with QID param with a call to
newly added nvme_alloc_request() and nvme_alloc_request_qid()
based on the qid value set in the __nvme_submit_sync_cmd().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: use consistent macro name for timeout

This is purely a clenaup patch, add prefix NVME to the ADMIN_TIMEOUT to
make consistent with NVME_IO_TIMEOUT.

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

nvme: simplify nvme_req_qid()

Use the request's '->mq_hctx->queue_num' directly to simplify the
nvme_req_qid() function.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: directly cache command effects log

Remove the struct used for tracking known command effects logs in a
list. This is now saved in an xarray that doesn't use these elements.
Instead, store the log directly instead of the wrapper struct.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce nvme_sync_io_queues

Introduce sync io queues for some scenarios which just only need sync
io queues not sync all queues.

Signed-off-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: use queuedata for nvme_req_qid

The request's rq_disk isn't set for passthrough IO commands, so tracing
uses qid 0 for these which incorrectly decodes as an admin command. Use
the request_queue's queuedata instead since that value is always set for
the IO queues, and never set for the admin queue.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove the disk argument to nvme_update_zone_info

The queue can trivially be derived from the nvme_ns structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>

nvme: fix initialization of the zone bitmaps

The removal of the ->revalidate_disk method broke the initialization of
the zone bitmaps, as nvme_revalidate_disk now never gets called during
initialization.

Move the zone related code from nvme_revalidate_disk into a new helper in
zns.c, and call it from nvme_alloc_ns in addition to nvme_validate_ns to
ensure the zone bitmaps are initialized during probe.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>

nvme: use an xarray to lookup the Commands Supported and Effects log

When using linked list we have to open code the locking, search, and
destroy operations with the loops even if data structure doesn't fall
into the fast path.

One of the main advantage of having XArray to store, search, and remove
items is that it handles all the locking by itself, avoids the loops
when using linked lists, provides clear API to replace the linked list's
search and destroy loops.

This patch replaces the ctrl->cel list with XArray and removes :-

a. Extra code needed for the linked list for ctrl->cel item management
such as nvme_find_cel().
b. Destroy loop in the nvme_free_ctrl().
c. Explicit insertion locking in the nvme_get_effects_log().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: lift the file open code from nvme_ctrl_get_by_path

Lift opening the file open/close code from nvme_ctrl_get_by_path into
the caller, just keeping a simple nvme_ctrl_from_file() helper.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: refactored a bit, split the bug fixes into a separate prep patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

nvme: return errors for hwmon init

Initializing the nvme hwmon retrieves a log from the controller. If the
controller is broken, we need to return the appropriate error so that
subsequent initialization doesn't attempt to continue.

Reported-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: Revert: Fix controller creation races with teardown flow

The indicated patch introduced a barrier in the sysfs_delete attribute
for the controller that rejects the request if the controller isn't
created. "Created" is defined as at least 1 call to nvme_start_ctrl().

This is problematic in error-injection testing. If an error occurs on
the initial attempt to create an association and the controller enters
reconnect(s) attempts, the admin cannot delete the controller until
either there is a successful association created or ctrl_loss_tmo
times out.

Where this issue is particularly hurtful is when the "admin" is the
nvme-cli, it is performing a connection to a discovery controller, and
it is initiated via auto-connect scripts. With the FC transport, if the
first connection attempt fails, the controller enters a normal reconnect
state but returns control to the cli thread that created the controller.
In this scenario, the cli attempts to read the discovery log via ioctl,
which fails, causing the cli to see it as an empty log and then proceeds
to delete the discovery controller. The delete is rejected and the
controller is left live. If the discovery controller reconnect then
succeeds, there is no action to delete it, and it sits live doing nothing.

Cc: <stable@vger.kernel.org> # v5.7+
Fixes: ce1518139e69 ("nvme: Fix controller creation races with teardown flow")
Signed-off-by: James Smart <james.smart@broadcom.com>
CC: Israel Rukshin <israelr@mellanox.com>
CC: Max Gurtovoy <maxg@mellanox.com>
CC: Christoph Hellwig <hch@lst.de>
CC: Keith Busch <kbusch@kernel.org>
CC: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: don't call revalidate_disk from nvme_set_queue_dying

In nvme_set_queue_dying we really just want to ensure the disk and bdev
sizes are set to zero. Going through revalidate_disk leads to a somewhat
arcance and complex callchain relying on special behavior in a few
places. Instead just lift the set_capacity directly to
nvme_set_queue_dying, and rename and move the nvme_mpath_update_disk_size
helper so that we can use it in nvme_set_queue_dying to propagate the
size to the bdev without detours.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: replace bd_set_size with bd_set_nr_sectors

Replace bd_set_size with a version that takes the number of sectors
instead, as that fits most of the current and future callers much better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: have nvme_wait_freeze_timeout return if it timed out

Users can detect if the wait has completed or not and take appropriate
actions based on this information (e.g. weather to continue
initialization or rather fail and schedule another initialization
attempt).

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: just check the status code type in nvme_is_path_error

Check the SCT sub-field for a path related status instead of enumerating
invididual status code. As of NVMe 1.4 this adds "Internal Path Error"
and "Controller Pathing Error" to the list, but it also future proofs for
additional status codes added to the category.

Suggested-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: refactor command completion

Lift all the code to decide the dispostition of a completed command
from nvme_complete_rq and nvme_failover_req into a new helper, which
returns an emum of the potential actions. nvme_complete_rq then
just switches on those and calls the proper helper for the action.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: rename and document nvme_end_request

nvme_end_request is a bit misnamed, as it wraps around the
blk_mq_complete_* API. It's semantics also are non-trivial, so give it
a more descriptive name and add a comment explaining the semantics.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add a Identify Namespace Identification Descriptor list quirk

Add a quirk for a device that does not support the Identify Namespace
Identification Descriptor list despite claiming 1.3 compliance.

Fixes: ea43d9709f72 ("nvme: fix identify error status silent ignore")
Reported-by: Ingo Brunberg <ingo_brunberg@web.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Ingo Brunberg <ingo_brunberg@web.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: export nvme_find_get_ns() and nvme_put_ns()

nvme_find_get_ns() and nvme_put_ns() are required by the target passthru
code and are exported under the NVME_TARGET_PASSTHRU namespace.

Based-on-a-patch-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce nvme_ctrl_get_by_path()

nvme_ctrl_get_by_path() is analogous to blkdev_get_by_path() except it
gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0).
It makes use of filp_open() to open the file and uses the private
data to obtain a pointer to the struct nvme_ctrl. If the fops of the
file do not match, -EINVAL is returned.

The purpose of this function is to support NVMe-OF target passthru
and is exported under the NVME_TARGET_PASSTHRU namespace.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce nvme_execute_passthru_rq to call nvme_passthru_[start|end]()

Introduce a new nvme_execute_passthru_rq() helper which calls
nvme_passthru_[start|end]() around blk_execute_rq(). This ensures
all passthru calls (including nvme_submit_io()) will be wrapped
appropriately.

nvme_execute_passthru_rq() will also be useful for the nvmet passthru
code and is exported in the NVME_TARGET_PASSTHRU namespace.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: create helper function to obtain command effects

Separate the code to obtain command effects from the code
to start a passthru request and move the nvme_passthru_start() and
nvme_passthru_end() functions up above nvme_submit_user_cmd() in order
that they may be used in a new helper a subsequent patch.

The new helper function will be necessary for nvmet passthru
code to determine if we need to change out of interrupt context
to handle the effects. It is exported in the NVME_TARGET_PASSTHRU
namespace.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: fix deadlock in disconnect during scan_work and/or ana_work

A deadlock happens in the following scenario with multipath:
1) scan_work(nvme0) detects a new nsid while nvme0
is an optimized path to it, path nvme1 happens to be
inaccessible.

2) Before scan_work is complete nvme0 disconnect is initiated
nvme_delete_ctrl_sync() sets nvme0 state to NVME_CTRL_DELETING

3) scan_work(1) attempts to submit IO,
but nvme_path_is_optimized() observes nvme0 is not LIVE.
Since nvme1 is a possible path IO is requeued and scan_work hangs.

--
Workqueue: nvme-wq nvme_scan_work [nvme_core]
kernel: Call Trace:
kernel: __schedule+0x2b9/0x6c0
kernel: schedule+0x42/0xb0
kernel: io_schedule+0x16/0x40
kernel: do_read_cache_page+0x438/0x830
kernel: read_cache_page+0x12/0x20
kernel: read_dev_sector+0x27/0xc0
kernel: read_lba+0xc1/0x220
kernel: efi_partition+0x1e6/0x708
kernel: check_partition+0x154/0x244
kernel: rescan_partitions+0xae/0x280
kernel: __blkdev_get+0x40f/0x560
kernel: blkdev_get+0x3d/0x140
kernel: __device_add_disk+0x388/0x480
kernel: device_add_disk+0x13/0x20
kernel: nvme_mpath_set_live+0x119/0x140 [nvme_core]
kernel: nvme_update_ns_ana_state+0x5c/0x60 [nvme_core]
kernel: nvme_set_ns_ana_state+0x1e/0x30 [nvme_core]
kernel: nvme_parse_ana_log+0xa1/0x180 [nvme_core]
kernel: nvme_mpath_add_disk+0x47/0x90 [nvme_core]
kernel: nvme_validate_ns+0x396/0x940 [nvme_core]
kernel: nvme_scan_work+0x24f/0x380 [nvme_core]
kernel: process_one_work+0x1db/0x380
kernel: worker_thread+0x249/0x400
kernel: kthread+0x104/0x140
--

4) Delete also hangs in flush_work(ctrl->scan_work)
from nvme_remove_namespaces().

Similiarly a deadlock with ana_work may happen: if ana_work has started
and calls nvme_mpath_set_live and device_add_disk, it will
trigger I/O. When we trigger disconnect I/O will block because
our accessible (optimized) path is disconnecting, but the alternate
path is inaccessible, so I/O blocks. Then disconnect tries to flush
the ana_work and hangs.

[ 605.550896] Workqueue: nvme-wq nvme_ana_work [nvme_core]
[ 605.552087] Call Trace:
[ 605.552683] __schedule+0x2b9/0x6c0
[ 605.553507] schedule+0x42/0xb0
[ 605.554201] io_schedule+0x16/0x40
[ 605.555012] do_read_cache_page+0x438/0x830
[ 605.556925] read_cache_page+0x12/0x20
[ 605.557757] read_dev_sector+0x27/0xc0
[ 605.558587] amiga_partition+0x4d/0x4c5
[ 605.561278] check_partition+0x154/0x244
[ 605.562138] rescan_partitions+0xae/0x280
[ 605.563076] __blkdev_get+0x40f/0x560
[ 605.563830] blkdev_get+0x3d/0x140
[ 605.564500] __device_add_disk+0x388/0x480
[ 605.565316] device_add_disk+0x13/0x20
[ 605.566070] nvme_mpath_set_live+0x5e/0x130 [nvme_core]
[ 605.567114] nvme_update_ns_ana_state+0x2c/0x30 [nvme_core]
[ 605.568197] nvme_update_ana_state+0xca/0xe0 [nvme_core]
[ 605.569360] nvme_parse_ana_log+0xa1/0x180 [nvme_core]
[ 605.571385] nvme_read_ana_log+0x76/0x100 [nvme_core]
[ 605.572376] nvme_ana_work+0x15/0x20 [nvme_core]
[ 605.573330] process_one_work+0x1db/0x380
[ 605.574144] worker_thread+0x4d/0x400
[ 605.574896] kthread+0x104/0x140
[ 605.577205] ret_from_fork+0x35/0x40
[ 605.577955] INFO: task nvme:14044 blocked for more than 120 seconds.
[ 605.579239] Tainted: G OE 5.3.5-050305-generic #201910071830
[ 605.580712] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 605.582320] nvme D 0 14044 14043 0x00000000
[ 605.583424] Call Trace:
[ 605.583935] __schedule+0x2b9/0x6c0
[ 605.584625] schedule+0x42/0xb0
[ 605.585290] schedule_timeout+0x203/0x2f0
[ 605.588493] wait_for_completion+0xb1/0x120
[ 605.590066] __flush_work+0x123/0x1d0
[ 605.591758] __cancel_work_timer+0x10e/0x190
[ 605.593542] cancel_work_sync+0x10/0x20
[ 605.594347] nvme_mpath_stop+0x2f/0x40 [nvme_core]
[ 605.595328] nvme_stop_ctrl+0x12/0x50 [nvme_core]
[ 605.596262] nvme_do_delete_ctrl+0x3f/0x90 [nvme_core]
[ 605.597333] nvme_sysfs_delete+0x5c/0x70 [nvme_core]
[ 605.598320] dev_attr_store+0x17/0x30

Fix this by introducing a new state: NVME_CTRL_DELETE_NOIO, which will
indicate the phase of controller deletion where I/O cannot be allowed
to access the namespace. NVME_CTRL_DELETING still allows mpath I/O to
be issued to the bottom device, and only after we flush the ana_work
and scan_work (after nvme_stop_ctrl and nvme_prep_remove_namespaces)
we change the state to NVME_CTRL_DELETING_NOIO. Also we prevent ana_work
from re-firing by aborting early if we are not LIVE, so we should be safe
here.

In addition, change the transport drivers to follow the updated state
machine.

Fixes: 0d0b660f214d ("nvme: add ANA support")
Reported-by: Anton Eidelman <anton@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: document nvme controller states

We are starting to see some non-trivial states
so lets start documenting them.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-core: replace ctrl page size with a macro

Saving the nvme controller's page size was from a time when the driver
tried to use different sized pages, but this value is always set to
a constant, and has been this way for some time. Remove the 'page_size'
field and replace its usage with the constant value.

This also lets the compiler make some micro-optimizations in the io
path, and that's always a good thing.

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

nvme: explicitly update mpath disk capacity on revalidation

Commit 3b4b19721ec652 ("nvme: fix possible deadlock when I/O is
blocked") reverted multipath head disk revalidation due to deadlocks
caused by holding the bd_mutex during revalidate.

Updating the multipath disk blockdev size is still required though for
userspace to be able to observe any resizing while the device is
mounted. Directly update the bdev inode size to avoid unnecessarily
holding the bdev->bd_mutex.

Fixes: 3b4b19721ec652 ("nvme: fix possible deadlock when I/O is
blocked")

Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: support for zoned namespaces

Add support for NVM Express Zoned Namespaces (ZNS) Command Set defined
in NVM Express TP4053. Zoned namespaces are discovered based on their
Command Set Identifier reported in the namespaces Namespace
Identification Descriptor list. A successfully discovered Zoned
Namespace will be registered with the block layer as a host managed
zoned block device with Zone Append command support. A namespace that
does not support append is not supported by the driver.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Signed-off-by: Ajay Joshi <ajay.joshi@wdc.com>
Signed-off-by: Aravind Ramesh <aravind.ramesh@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Matias Bjørling <matias.bjorling@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Keith Busch <keith.busch@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: support for multiple Command Sets Supported and Effects log pages

The Commands Supported and Effects log page was extended with a CSI
field that enables the host to query the log page for each command set
supported. Retrieve this log page for each command set that an attached
namespace supports, and save a pointer to that log in the namespace head.

Reviewed-by: Matias Bjørling <matias.bjorling@wdc.com>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Keith Busch <keith.busch@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: implement multiple I/O Command Set support

Implements support for multiple I/O Command Sets. NVMe TP 4056
introduces a method to enumerate multiple command sets per namespace. If
the command set is exposed, this method for enumeration will be used
instead of the traditional method that uses the CC.CSS register command
set register for command set identification.

For namespaces where the Command Set Identifier is not supported or
recognized, the specific namespace will not be created.

Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Matias Bjørling <matias.bjorling@wdc.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

block: move ->make_request_fn to struct block_device_operations

The make_request_fn is a little weird in that it sits directly in
struct request_queue instead of an operation vector. Replace it with
a block_device_operations method called submit_bio (which describes much
better what it does). Also remove the request_queue argument to it, as
the queue can be derived pretty trivially from the bio.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-multipath: fix deadlock due to head->lock

In the following scenario scan_work and ana_work will deadlock:

When scan_work calls nvme_mpath_add_disk() this holds ana_lock
and invokes nvme_parse_ana_log(), which may issue IO
in device_add_disk() and hang waiting for an accessible path.

While nvme_mpath_set_live() only called when nvme_state_is_live(),
a transition may cause NVME_SC_ANA_TRANSITION and requeue the IO.

Since nvme_mpath_set_live() holds ns->head->lock, an ana_work on
ANY ctrl will not be able to complete nvme_mpath_set_live()
on the same ns->head, which is required in order to update
the new accessible path and remove NVME_NS_ANA_PENDING..
Therefore IO never completes: deadlock [1].

Fix:
Move device_add_disk out of the head->lock and protect it with an
atomic test_and_set for a new NVME_NS_HEAD_HAS_DISK bit.

[1]:
kernel: INFO: task kworker/u8:2:160 blocked for more than 120 seconds.
kernel: Tainted: G OE 5.3.5-050305-generic #201910071830
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: kworker/u8:2 D 0 160 2 0x80004000
kernel: Workqueue: nvme-wq nvme_ana_work [nvme_core]
kernel: Call Trace:
kernel: __schedule+0x2b9/0x6c0
kernel: schedule+0x42/0xb0
kernel: schedule_preempt_disabled+0xe/0x10
kernel: __mutex_lock.isra.0+0x182/0x4f0
kernel: __mutex_lock_slowpath+0x13/0x20
kernel: mutex_lock+0x2e/0x40
kernel: nvme_update_ns_ana_state+0x22/0x60 [nvme_core]
kernel: nvme_update_ana_state+0xca/0xe0 [nvme_core]
kernel: nvme_parse_ana_log+0xa1/0x180 [nvme_core]
kernel: nvme_read_ana_log+0x76/0x100 [nvme_core]
kernel: nvme_ana_work+0x15/0x20 [nvme_core]
kernel: process_one_work+0x1db/0x380
kernel: worker_thread+0x4d/0x400
kernel: kthread+0x104/0x140
kernel: ret_from_fork+0x35/0x40
kernel: INFO: task kworker/u8:4:439 blocked for more than 120 seconds.
kernel: Tainted: G OE 5.3.5-050305-generic #201910071830
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: kworker/u8:4 D 0 439 2 0x80004000
kernel: Workqueue: nvme-wq nvme_scan_work [nvme_core]
kernel: Call Trace:
kernel: __schedule+0x2b9/0x6c0
kernel: schedule+0x42/0xb0
kernel: io_schedule+0x16/0x40
kernel: do_read_cache_page+0x438/0x830
kernel: read_cache_page+0x12/0x20
kernel: read_dev_sector+0x27/0xc0
kernel: read_lba+0xc1/0x220
kernel: efi_partition+0x1e6/0x708
kernel: check_partition+0x154/0x244
kernel: rescan_partitions+0xae/0x280
kernel: __blkdev_get+0x40f/0x560
kernel: blkdev_get+0x3d/0x140
kernel: __device_add_disk+0x388/0x480
kernel: device_add_disk+0x13/0x20
kernel: nvme_mpath_set_live+0x119/0x140 [nvme_core]
kernel: nvme_update_ns_ana_state+0x5c/0x60 [nvme_core]
kernel: nvme_mpath_add_disk+0xbe/0x100 [nvme_core]
kernel: nvme_validate_ns+0x396/0x940 [nvme_core]
kernel: nvme_scan_work+0x256/0x390 [nvme_core]
kernel: process_one_work+0x1db/0x380
kernel: worker_thread+0x4d/0x400
kernel: kthread+0x104/0x140
kernel: ret_from_fork+0x35/0x40

Fixes: 0d0b660f214d ("nvme: add ANA support")
Signed-off-by: Anton Eidelman <anton@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: use blk_mq_complete_request_remote to avoid an indirect function call

Use the new blk_mq_complete_request_remote helper to avoid an indirect
function call in the completion fast path.

Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: move failure injection out of blk_mq_complete_request

Move the call to blk_should_fake_timeout out of blk_mq_complete_request
and into the drivers, skipping call sites that are obvious error
handlers, and remove the now superflous blk_mq_force_complete_rq helper.
This ensures we don't keep injecting errors into completions that just
terminate the Linux request after the hardware has been reset or the
command has been aborted.

Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove the error argument to the block_bio_complete tracepoint

The status can be trivially derived from the bio itself. That also avoid
callers like NVMe to incorrectly pass a blk_status_t instead of the errno,
and the overhead of translating the blk_status_t to the errno in the I/O
completion fast path when no tracing is enabled.

Fixes: 35fe0d12c8a3 ("nvme: trace bio completion")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: introduce NVME_INLINE_METADATA_SG_CNT

SGL size of metadata is usually small. Thus, 1 inline sg should cover
most cases. The macro will be used for pre-allocate a single SGL entry
for metadata. The preallocation of small inline SGLs depends on SG_CHAIN
capability so if the ARCH doesn't support SG_CHAIN, use the runtime
allocation for the SGL. This patch is a preparation for adding metadata
(T10-PI) over fabric support.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce max_integrity_segments ctrl attribute

This patch doesn't change any logic, and is needed as a preparation
for adding PI support for fabrics drivers that will use an extended
LBA format for metadata and will support more than 1 integrity segment.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: make nvme_ns_has_pi accessible to transports

Move the nvme_ns_has_pi() inline from core.c to the nvme.h header.
This allows use by the transports.

Signed-off-by: James Smart <jsmart2021@gmail.com>
[maxg: added a comment for nvme_ns_has_pi()]
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce NVME_NS_METADATA_SUPPORTED flag

This is a preparation for adding support for metadata in fabric
controllers. New flag will imply that NVMe namespace supports getting
metadata that was originally generated by host's block layer.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce namespace features flag

Replace the specific ext boolean (that implies on extended LBA format)
with a feature in the new namespace features flag. This is a preparation
for adding more namespace features (such as metadata specific features).

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: delete an unnecessary declaration

The nvme_put_ctrl() is implemented earlier as an inline function so
this declaration isn't required.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: consolidate chunk_sectors settings

Move the quirked chunk_sectors setting to the same location as noiob so
one place registers this setting. And since the noiob value is only used
locally, remove the member from struct nvme_ns.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: check namespace head shared property

Reject a new shared namespace if a duplicate unshared namespace exists.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: provide num dword helper

Various nvme commands use a zeroes based number of dwords field. Create
a helper function to convert byte lengths to this format.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Fix controller creation races with teardown flow

Calling nvme_sysfs_delete() when the controller is in the middle of
creation may cause several bugs. If the controller is in NEW state we
remove delete_controller file and don't delete the controller. The user
will not be able to use nvme disconnect command on that controller again,
although the controller may be active. Other bugs may happen if the
controller is in the middle of create_ctrl callback and
nvme_do_delete_ctrl() starts. For example, freeing I/O tagset at
nvme_do_delete_ctrl() before it was allocated at create_ctrl callback.

To fix all those races don't allow the user to delete the controller
before it was fully created.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme-multipath: do not reset on unknown status

The nvme multipath error handling defaults to controller reset if the
error is unknown. There are, however, no existing nvme status codes that
indicate a reset should be used, and resetting causes unnecessary
disruption to the rest of IO.

Change nvme's error handling to first check if failover should happen.
If not, let the normal error handling take over rather than reset the
controller.

Based-on-a-patch-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: John Meneghini <johnm@netapp.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme-rdma: Avoid preallocating big SGL for data

nvme_rdma_alloc_tagset() preallocates a big buffer for the IO SGL based
on SG_CHUNK_SIZE.

Modern DMA engines are often capable of dealing with very big segments so
the SG_CHUNK_SIZE is often too big. SG_CHUNK_SIZE results in a static 4KB
SGL allocation per command.

If a controller has lots of deep queues, preallocation for the sg list can
consume substantial amounts of memory. For nvme-rdma, nr_hw_queues can be
128 and each queue's depth 128. This means the resulting preallocation
for the data SGL is 128*128*4K = 64MB per controller.

Switch to runtime allocation for SGL for lists longer than 2 entries. This
is the approach used by NVMe PCI so it should be reasonable for NVMeOF as
well. Runtime SGL allocation has always been the case for the legacy I/O
path so this is nothing new.

The preallocated small SGL depends on SG_CHAIN so if the ARCH doesn't
support SG_CHAIN, use only runtime allocation for the SGL.

We didn't notice of a performance degradation, since for small IOs we'll
use the inline SG and for the bigger IOs the allocation of a bigger SGL
from slab is fast enough.

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: hwmon: add quirk to avoid changing temperature threshold

This adds a new quirk NVME_QUIRK_NO_TEMP_THRESH_CHANGE to avoid changing
the value of the temperature threshold feature for specific devices that
show undesirable behavior.

Guenter reported:

"On my Intel NVME drive (SSDPEKKW512G7), writing any minimum limit on the
Composite temperature sensor results in a temperature warning, and that
warning is sticky until I reset the controller.

It doesn't seem to matter which temperature I write; writing -273000 has
the same result."

The Intel NVMe has the latest firmware version installed, so this isn't
a problem that was ever fixed.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Jean Delvare <jdelvare@suse.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: Add hardware monitoring support

nvme devices report temperature information in the controller information
(for limits) and in the smart log. Currently, the only means to retrieve
this information is the nvme command line interface, which requires
super-user privileges.

At the same time, it would be desirable to be able to use NVMe temperature
information for thermal control.

This patch adds support to read NVMe temperatures from the kernel using the
hwmon API and adds temperature zones for NVMe drives. The thermal subsystem
can use this information to set thermal policies, and userspace can access
it using libsensors and/or the "sensors" command.

Example output from the "sensors" command:

nvme0-pci-0100
Adapter: PCI adapter
Composite: +39.0°C (high = +85.0°C, crit = +85.0°C)
Sensor 1: +39.0°C
Sensor 2: +41.0°C

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: Introduce nvme_lba_to_sect()

Introduce the new helper function nvme_lba_to_sect() to convert a device
logical block number to a 512B sector number. Use this new helper in
obvious places, cleaning up the code.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Cleanup and rename nvme_block_nr()

Rename nvme_block_nr() to nvme_sect_to_lba() and use SECTOR_SHIFT
instead of its hard coded value 9. Also add a comment to decribe this
helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: introduce nvme_is_aen_req function

This function improves code readability and reduces code duplication.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Wait for reset state when required

Prevent simultaneous controller disabling/enabling tasks from interfering
with each other through a function to wait until the task successfully
transitioned the controller to the RESETTING state. This ensures disabling
the controller will not be interrupted by another reset path, otherwise
a concurrent reset may leave the controller in the wrong state.

Tested-by: Edmund Nadolski <edmund.nadolski@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: Remove ADMIN_ONLY state

The admin only state was intended to fence off actions that don't
apply to a non-IO capable controller. The only actual user of this is
the scan_work, and pci was the only transport to ever set this state.
The consequence of having this state is placing an additional burden on
every other action that applies to both live and admin only controllers.

Remove the admin only state and place the admin only burden on the only
place that actually cares: scan_work.

This also prepares to make it easier to temporarily pause a LIVE state
so that we don't need to remember which state the controller had been in
prior to the pause.

Tested-by: Edmund Nadolski <edmund.nadolski@intel.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvme: Move ctrl sqsize to generic space

This isn't specific to fabrics.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: make fabrics command run on a separate request queue

We have a fundamental issue that fabric commands use the admin_q.
The reason is, that admin-connect, register reads and writes and
admin commands cannot be guaranteed ordering while we are running
controller resets.

For example, when we reset a controller we perform:
1. disable the controller
2. teardown the admin queue
3. re-establish the admin queue
4. enable the controller

In order to perform (3), we need to unquiesce the admin queue, however
we may have some admin commands that are already pending on the
quiesced admin_q and will immediate execute when we unquiesce it before
we execute (4). The host must not send admin commands to the controller
before enabling the controller.

To fix this, we have the fabric commands (admin connect and property
get/set, but not I/O queue connect) use a separate fabrics_q and make
sure to quiesce the admin_q before we disable the controller, and
unquiesce it only after we enable the controller.

This fixes the error prints from nvmet in a controller reset storm test:
kernel: nvmet: got cmd 6 while CC.EN == 0 on qid = 0
Which indicate that the host is sending an admin command when the
controller is not enabled.

Reviewed-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme-pci: Support shared tags across queues for Apple 2018 controllers

Another issue with the Apple T2 based 2018 controllers seem to be
that they blow up (and shut the machine down) if there's a tag
collision between the IO queue and the Admin queue.

My suspicion is that they use our tags for their internal tracking
and don't mix them with the queue id. They also seem to not like
when tags go beyond the IO queue depth, ie 128 tags.

This adds a quirk that marks tags 0..31 of the IO queue reserved

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme-pci: Add support for Apple 2018+ models

Based on reverse engineering and original patch by

Paul Pawlowski <paul@mrarm.io>

This adds support for Apple weird implementation of NVME in their
2018 or later machines. It accounts for the twice-as-big SQ entries
for the IO queues, and the fact that only interrupt vector 0 appears
to function properly.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: trace bio completion

When native multipathing is enabled we cannot enable blktrace for
the underlying paths, so any completion is never traced.

Signed-off-by: Hannes Reinecke <hare@suse.com>
[fixed-up by Mikhail for non-multipath-build]
Signed-off-by: Mikhail Skorzhinskii <mskorzhinskiy@solarflare.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: don't pass cap to nvme_disable_ctrl

All seem to call it with ctrl->cap so no need to pass it
at all.

Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: move sqsize setting to the core

nvme_enable_ctrl reads the cap register right after, so
no need to do that locally in the transport driver. Have
sqsize setting in nvme_init_identify.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: Add quirk for LiteON CL1 devices running FW 22301111

One of the components in LiteON CL1 device has limitations that
can be encountered based upon boundary race conditions using the
nvme bus specific suspend to idle flow.

When this situation occurs the drive doesn't resume properly from
suspend-to-idle.

LiteON has confirmed this problem and fixed in the next firmware
version. As this firmware is already in the field, avoid running
nvme specific suspend to idle flow.

Fixes: d916b1be94b6 ("nvme-pci: use host managed power state for suspend")
Link: http://lists.infradead.org/pipermail/linux-nvme/2019-July/thread.html
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Charles Hyde <charles.hyde@dellteam.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: fix controller removal race with scan work

With multipath enabled, nvme_scan_work() can read from the device
(through nvme_mpath_add_disk()) and hang [1]. However, with fabrics,
once ctrl->state is set to NVME_CTRL_DELETING, the reads will hang
(see nvmf_check_ready()) and the mpath stack device make_request
will block if head->list is not empty. However, when the head->list
consistst of only DELETING/DEAD controllers, we should actually not
block, but rather fail immediately.

In addition, before we go ahead and remove the namespaces, make sure
to clear the current path and kick the requeue list so that the
request will fast fail upon requeuing.

[1]:
--
INFO: task kworker/u4:3:166 blocked for more than 120 seconds.
Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:3 D 0 166 2 0x80004000
Workqueue: nvme-wq nvme_scan_work
Call Trace:
__schedule+0x851/0x1400
schedule+0x99/0x210
io_schedule+0x21/0x70
do_read_cache_page+0xa57/0x1330
read_cache_page+0x4a/0x70
read_dev_sector+0xbf/0x380
amiga_partition+0xc4/0x1230
check_partition+0x30f/0x630
rescan_partitions+0x19a/0x980
__blkdev_get+0x85a/0x12f0
blkdev_get+0x2a5/0x790
__device_add_disk+0xe25/0x1250
device_add_disk+0x13/0x20
nvme_mpath_set_live+0x172/0x2b0
nvme_update_ns_ana_state+0x130/0x180
nvme_set_ns_ana_state+0x9a/0xb0
nvme_parse_ana_log+0x1c3/0x4a0
nvme_mpath_add_disk+0x157/0x290
nvme_validate_ns+0x1017/0x1bd0
nvme_scan_work+0x44d/0x6a0
process_one_work+0x7d7/0x1240
worker_thread+0x8e/0xff0
kthread+0x2c3/0x3b0
ret_from_fork+0x35/0x40

INFO: task kworker/u4:1:1034 blocked for more than 120 seconds.
Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:1 D 0 1034 2 0x80004000
Workqueue: nvme-delete-wq nvme_delete_ctrl_work
Call Trace:
__schedule+0x851/0x1400
schedule+0x99/0x210
schedule_timeout+0x390/0x830
wait_for_completion+0x1a7/0x310
__flush_work+0x241/0x5d0
flush_work+0x10/0x20
nvme_remove_namespaces+0x85/0x3d0
nvme_do_delete_ctrl+0xb4/0x1e0
nvme_delete_ctrl_work+0x15/0x20
process_one_work+0x7d7/0x1240
worker_thread+0x8e/0xff0
kthread+0x2c3/0x3b0
ret_from_fork+0x35/0x40
--

Reported-by: Logan Gunthorpe <logang@deltatee.com>
Tested-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: fix a possible deadlock when passthru commands sent to a multipath device

When the user issues a command with side effects, we will end up freezing
the namespace request queue when updating disk info (and the same for
the corresponding mpath disk node).

However, we are not freezing the mpath node request queue,
which means that mpath I/O can still come in and block on blk_queue_enter
(called from nvme_ns_head_make_request -> direct_make_request).

This is a deadlock, because blk_queue_enter will block until the inner
namespace request queue is unfroze, but that process is blocked because
the namespace revalidation is trying to update the mpath disk info
and freeze its request queue (which will never complete because
of the I/O that is blocked on blk_queue_enter).

Fix this by freezing all the subsystem nsheads request queues before
executing the passthru command. Given that these commands are infrequent
we should not worry about this temporary I/O freeze to keep things sane.

Here is the matching hang traces:
--
[ 374.465002] INFO: task systemd-udevd:17994 blocked for more than 122 seconds.
[ 374.472975] Not tainted 5.2.0-rc3-mpdebug+ #42
[ 374.478522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 374.487274] systemd-udevd D 0 17994 1 0x00000000
[ 374.493407] Call Trace:
[ 374.496145] __schedule+0x2ef/0x620
[ 374.500047] schedule+0x38/0xa0
[ 374.503569] blk_queue_enter+0x139/0x220
[ 374.507959] ? remove_wait_queue+0x60/0x60
[ 374.512540] direct_make_request+0x60/0x130
[ 374.517219] nvme_ns_head_make_request+0x11d/0x420 [nvme_core]
[ 374.523740] ? generic_make_request_checks+0x307/0x6f0
[ 374.529484] generic_make_request+0x10d/0x2e0
[ 374.534356] submit_bio+0x75/0x140
[ 374.538163] ? guard_bio_eod+0x32/0xe0
[ 374.542361] submit_bh_wbc+0x171/0x1b0
[ 374.546553] block_read_full_page+0x1ed/0x330
[ 374.551426] ? check_disk_change+0x70/0x70
[ 374.556008] ? scan_shadow_nodes+0x30/0x30
[ 374.560588] blkdev_readpage+0x18/0x20
[ 374.564783] do_read_cache_page+0x301/0x860
[ 374.569463] ? blkdev_writepages+0x10/0x10
[ 374.574037] ? prep_new_page+0x88/0x130
[ 374.578329] ? get_page_from_freelist+0xa2f/0x1280
[ 374.583688] ? __alloc_pages_nodemask+0x179/0x320
[ 374.588947] read_cache_page+0x12/0x20
[ 374.593142] read_dev_sector+0x2d/0xd0
[ 374.597337] read_lba+0x104/0x1f0
[ 374.601046] find_valid_gpt+0xfa/0x720
[ 374.605243] ? string_nocheck+0x58/0x70
[ 374.609534] ? find_valid_gpt+0x720/0x720
[ 374.614016] efi_partition+0x89/0x430
[ 374.618113] ? string+0x48/0x60
[ 374.621632] ? snprintf+0x49/0x70
[ 374.625339] ? find_valid_gpt+0x720/0x720
[ 374.629828] check_partition+0x116/0x210
[ 374.634214] rescan_partitions+0xb6/0x360
[ 374.638699] __blkdev_reread_part+0x64/0x70
[ 374.643377] blkdev_reread_part+0x23/0x40
[ 374.647860] blkdev_ioctl+0x48c/0x990
[ 374.651956] block_ioctl+0x41/0x50
[ 374.655766] do_vfs_ioctl+0xa7/0x600
[ 374.659766] ? locks_lock_inode_wait+0xb1/0x150
[ 374.664832] ksys_ioctl+0x67/0x90
[ 374.668539] __x64_sys_ioctl+0x1a/0x20
[ 374.672732] do_syscall_64+0x5a/0x1c0
[ 374.676828] entry_SYSCALL_64_after_hwframe+0x44/0xa9

[ 374.738474] INFO: task nvmeadm:49141 blocked for more than 123 seconds.
[ 374.745871] Not tainted 5.2.0-rc3-mpdebug+ #42
[ 374.751419] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 374.760170] nvmeadm D 0 49141 36333 0x00004080
[ 374.766301] Call Trace:
[ 374.769038] __schedule+0x2ef/0x620
[ 374.772939] schedule+0x38/0xa0
[ 374.776452] blk_mq_freeze_queue_wait+0x59/0x100
[ 374.781614] ? remove_wait_queue+0x60/0x60
[ 374.786192] blk_mq_freeze_queue+0x1a/0x20
[ 374.790773] nvme_update_disk_info.isra.57+0x5f/0x350 [nvme_core]
[ 374.797582] ? nvme_identify_ns.isra.50+0x71/0xc0 [nvme_core]
[ 374.804006] __nvme_revalidate_disk+0xe5/0x110 [nvme_core]
[ 374.810139] nvme_revalidate_disk+0xa6/0x120 [nvme_core]
[ 374.816078] ? nvme_submit_user_cmd+0x11e/0x320 [nvme_core]
[ 374.822299] nvme_user_cmd+0x264/0x370 [nvme_core]
[ 374.827661] nvme_dev_ioctl+0x112/0x1d0 [nvme_core]
[ 374.833114] do_vfs_ioctl+0xa7/0x600
[ 374.837117] ? __audit_syscall_entry+0xdd/0x130
[ 374.842184] ksys_ioctl+0x67/0x90
[ 374.845891] __x64_sys_ioctl+0x1a/0x20
[ 374.850082] do_syscall_64+0x5a/0x1c0
[ 374.854178] entry_SYSCALL_64_after_hwframe+0x44/0xa9
--

Reported-by: James Puthukattukaran <james.puthukattukaran@oracle.com>
Tested-by: James Puthukattukaran <james.puthukattukaran@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: fix multipath crash when ANA is deactivated

Fix a crash with multipath activated. It happends when ANA log
page is larger than MDTS and because of that ANA is disabled.
The driver then tries to access unallocated buffer when connecting
to a nvme target. The signature is as follows:

[ 300.433586] nvme nvme0: ANA log page size (8208) larger than MDTS (8192).
[ 300.435387] nvme nvme0: disabling ANA support.
[ 300.437835] nvme nvme0: creating 4 I/O queues.
[ 300.459132] nvme nvme0: new ctrl: NQN "nqn.0.0.0", addr 10.91.0.1:8009
[ 300.464609] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[ 300.466342] #PF error: [normal kernel read fault]
[ 300.467385] PGD 0 P4D 0
[ 300.467987] Oops: 0000 [#1] SMP PTI
[ 300.468787] CPU: 3 PID: 50 Comm: kworker/u8:1 Not tainted 5.0.20kalray+ #4
[ 300.470264] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 300.471532] Workqueue: nvme-wq nvme_scan_work [nvme_core]
[ 300.472724] RIP: 0010:nvme_parse_ana_log+0x21/0x140 [nvme_core]
[ 300.474038] Code: 45 01 d2 d8 48 98 c3 66 90 0f 1f 44 00 00 41 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 08 48 8b af 20 0a 00 00 48 89 34 24 <66> 83 7d 08 00 0f 84 c6 00 00 00 44 8b 7d 14 49 89 d5 8b 55 10 48
[ 300.477374] RSP: 0018:ffffa50e80fd7cb8 EFLAGS: 00010296
[ 300.478334] RAX: 0000000000000001 RBX: ffff9130f1872258 RCX: 0000000000000000
[ 300.479784] RDX: ffffffffc06c4c30 RSI: ffff9130edad4280 RDI: ffff9130f1872258
[ 300.481488] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044
[ 300.483203] R10: 0000000000000220 R11: 0000000000000040 R12: ffff9130f18722c0
[ 300.484928] R13: ffff9130f18722d0 R14: ffff9130edad4280 R15: ffff9130f18722c0
[ 300.486626] FS: 0000000000000000(0000) GS:ffff9130f7b80000(0000) knlGS:0000000000000000
[ 300.488538] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 300.489907] CR2: 0000000000000008 CR3: 00000002365e6000 CR4: 00000000000006e0
[ 300.491612] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 300.493303] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 300.494991] Call Trace:
[ 300.495645] nvme_mpath_add_disk+0x5c/0xb0 [nvme_core]
[ 300.496880] nvme_validate_ns+0x2ef/0x550 [nvme_core]
[ 300.498105] ? nvme_identify_ctrl.isra.45+0x6a/0xb0 [nvme_core]
[ 300.499539] nvme_scan_work+0x2b4/0x370 [nvme_core]
[ 300.500717] ? __switch_to_asm+0x35/0x70
[ 300.501663] process_one_work+0x171/0x380
[ 300.502340] worker_thread+0x49/0x3f0
[ 300.503079] kthread+0xf8/0x130
[ 300.503795] ? max_active_store+0x80/0x80
[ 300.504690] ? kthread_bind+0x10/0x10
[ 300.505502] ret_from_fork+0x35/0x40
[ 300.506280] Modules linked in: nvme_tcp nvme_rdma rdma_cm iw_cm ib_cm ib_core nvme_fabrics nvme_core xt_physdev ip6table_raw ip6table_mangle ip6table_filter ip6_tables xt_comment iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_CHECKSUM iptable_mangle iptable_filter veth ebtable_filter ebtable_nat ebtables iptable_raw vxlan ip6_udp_tunnel udp_tunnel sunrpc joydev pcspkr virtio_balloon br_netfilter bridge stp llc ip_tables xfs libcrc32c ata_generic pata_acpi virtio_net virtio_console net_failover virtio_blk failover ata_piix serio_raw libata virtio_pci virtio_ring virtio
[ 300.514984] CR2: 0000000000000008
[ 300.515569] ---[ end trace faa2eefad7e7f218 ]---
[ 300.516354] RIP: 0010:nvme_parse_ana_log+0x21/0x140 [nvme_core]
[ 300.517330] Code: 45 01 d2 d8 48 98 c3 66 90 0f 1f 44 00 00 41 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 08 48 8b af 20 0a 00 00 48 89 34 24 <66> 83 7d 08 00 0f 84 c6 00 00 00 44 8b 7d 14 49 89 d5 8b 55 10 48
[ 300.520353] RSP: 0018:ffffa50e80fd7cb8 EFLAGS: 00010296
[ 300.521229] RAX: 0000000000000001 RBX: ffff9130f1872258 RCX: 0000000000000000
[ 300.522399] RDX: ffffffffc06c4c30 RSI: ffff9130edad4280 RDI: ffff9130f1872258
[ 300.523560] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044
[ 300.524734] R10: 0000000000000220 R11: 0000000000000040 R12: ffff9130f18722c0
[ 300.525915] R13: ffff9130f18722d0 R14: ffff9130edad4280 R15: ffff9130f18722c0
[ 300.527084] FS: 0000000000000000(0000) GS:ffff9130f7b80000(0000) knlGS:0000000000000000
[ 300.528396] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 300.529440] CR2: 0000000000000008 CR3: 00000002365e6000 CR4: 00000000000006e0
[ 300.530739] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 300.531989] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 300.533264] Kernel panic - not syncing: Fatal exception
[ 300.534338] Kernel Offset: 0x17c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 300.536227] ---[ end Kernel panic - not syncing: Fatal exception ]---

Condition check refactoring from Christoph Hellwig.

Signed-off-by: Marta Rybczynska <marta.rybczynska@kalray.eu>
Tested-by: Jean-Baptiste Riaux <jbriaux@kalray.eu>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: set physical block size and optimal I/O size

>From the NVMe 1.4 spec:

NSFEAT bit 4 if set to 1: indicates that the fields NPWG, NPWA, NPDG, NPDA,
and NOWS are defined for this namespace and should be used by the host for
I/O optimization;
[ ... ]
Namespace Preferred Write Granularity (NPWG): This field indicates the
smallest recommended write granularity in logical blocks for this namespace.
This is a 0's based value. The size indicated should be less than or equal
to Maximum Data Transfer Size (MDTS) that is specified in units of minimum
memory page size. The value of this field may change if the namespace is
reformatted. The size should be a multiple of Namespace Preferred Write
Alignment (NPWA). Refer to section 8.25 for how this field is utilized to
improve performance and endurance.
[ ... ]
Each Write, Write Uncorrectable, or Write Zeroes commands should address a
multiple of Namespace Preferred Write Granularity (NPWG) (refer to Figure
245) and Stream Write Size (SWS) (refer to Figure 515) logical blocks (as
expressed in the NLB field), and the SLBA field of the command should be
aligned to Namespace Preferred Write Alignment (NPWA) (refer to Figure 245)
for best performance.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: enable to inject errors into admin commands

This enables to inject errors into the commands submitted to the admin
queue.

It is useful to test error handling in the controller initialization.

# echo 100 > /sys/kernel/debug/nvme0/fault_inject/probability
# echo 1 > /sys/kernel/debug/nvme0/fault_inject/times
# echo 10 > /sys/kernel/debug/nvme0/fault_inject/space
# nvme reset /dev/nvme0
# dmesg
...
nvme nvme0: Could not set queue count (16385)
nvme nvme0: IO queues not created

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: prepare for fault injection into admin commands

Currenlty fault injection support for nvme only enables to inject errors
into the commands submitted to I/O queues.

In preparation for fault injection into the admin commands, this makes
the helper functions independent of struct nvme_ns.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: export get and set features

Future use intends to make use of both, so export these functions. And
since their implementation is identical except for the opcode, provide a
new function that implement both.

[akinobu.mita@gmail.com>: fix line over 80 characters]
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-pci: Sync queues on reset

A controller with multiple namespaces may have multiple request_queues with
their own timeout work. If a controller fails with IO outstanding to
diffent namespaces, each request queue may attempt to handle it, so
ensure there is no previously scheduled timeout work executing prior to
starting controller initialization by synchronizing with each queue.

Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>

nvme: mark nvme_core_init and nvme_core_exit static

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

nvme: disable Write Zeroes for qemu controllers

Qemu started out with a broken implementation of Write Zeroes written
by yours truly. Disable Write Zeroes on qemu for now, eventually
we need to go back and make all the qemu quirks version specific,
but that is left for another time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: convert to SPDX identifiers

Update license to use SPDX-License-Identifier instead of verbose license
text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: unexport nvme_delete_ctrl_sync()

Since nvme_delete_ctrl_sync() is not called from any other kernel module,
unexport it.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-multipath: round-robin I/O policy

Implement a simple round-robin I/O policy for multipathing. Path
selection is done in two rounds, first iterating across all optimized
paths, and if that doesn't return any valid paths, iterate over all
optimized and non-optimized paths. If no paths are found, use the
existing algorithm. Also add a sysfs attribute 'iopolicy' to switch
between the current NUMA-aware I/O policy and the 'round-robin' I/O
policy.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: lock NS list changes while handling command effects

If a controller supports the NS Change Notification, the namespace
scan_work is automatically triggered after attaching a new namespace.

Occasionally the namespace scan_work may append the new namespace to the
list before the admin command effects handling is completed. The effects
handling unfreezes namespaces, but if it unfreezes the newly attached
namespace, its request_queue freeze depth will be off and we'll hit the
warning in blk_mq_unfreeze_queue().

On the next namespace add, we will fail to freeze that queue due to the
previous bad accounting and deadlock waiting for frozen.

Fix that by preventing scan work from altering the namespace list while
command effects handling needs to pair freeze with unfreeze.

Reported-by: Wen Xiong <wenxiong@us.ibm.com>
Tested-by: Wen Xiong <wenxiong@us.ibm.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove the .stop_ctrl callout

It is used now just to flush error recovery and reconnect work items in
the RDMA and TCP transports, which can simply be moved to the
corresponding teardown routines.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: introduce NVME_QUIRK_IGNORE_DEV_SUBNQN

If a device provides an NQN it is expected to be globally unique.
Unfortunately some firmware revisions for Intel 760p/Pro 7600p devices did
not satisfy this requirement. In these circumstances if a system has >1
affected device then only one device is enabled. If this quirk is enabled
then the device supplied subnqn is ignored and we fallback to generating
one as if the field was empty. In this case we also suppress the version
check so we don't print a warning when the quirk is enabled.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: James Dingwall <james@dingwall.me.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-core: optionally poll sync commands

Pass poll bool to indicate that we need it to poll. This prepares us for
polling support in nvmf since connect is an I/O that will be queued
and has to be polled in order to complete. If poll is passed,
we call nvme_execute_rq_polled which sends the requests and polls
for its completion.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: provide fallback for discard alloc failure

When boxes are run near (or to) OOM, we have a problem with the discard
page allocation in nvme. If we fail allocating the special page, we
return busy, and it'll get retried. But since ordering is honored for
dispatch requests, we can keep retrying this same IO and failing. Behind
that IO could be requests that want to free memory, but they never get
the chance.

Allocate a fixed discard page per controller for a safe fallback, and use
that if the initial allocation fails.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add __exit annotation

Add __exit annotation to cleanup helper which is only
called once in the module.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

lightnvm: simplify geometry enumeration

Currently the geometry of an OCSSD is enumerated using a two step
approach:

First, nvm_register is called, the OCSSD identify command is issued,
and second the geometry sos and csecs values are read either from the
OCSSD identify if it is a 1.2 drive, or from the NVMe namespace data
structure if it is a 2.0 device.

This patch recombines it into a single step, such that nvm_register can
use the csecs and sos fields independent of which version is used. This
enables one to dynamically size the lightnvm subsystem dma pool.

Reviewed-by: Igor Konopko <igor.j.konopko@intel.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove unused function nvme_ctrl_ready

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: implement Enhanced Command Retry

A controller may have an internal state that is not able to successfully
process commands for a short duration. In such states, an immediate
command requeue is expected to fail. The driver may exceed its max
retry count, which permanently ends the command in failure when the same
command would succeed after waiting for the controller to be ready.

NVMe ratified TP 4033 provides a delay hint in the completion status
code for failed commands. Implement the retry delay based on the command
completion status and the controller's requested delay.

Note that requeued commands are handled per request_queue, not per
individual request. If multiple commands fail, the controller should
consistently report the desired delay time for retryable commands in
all CQEs, otherwise the requeue list may be kicked too soon.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: support traffic based keep-alive

If the controller supports traffic based keep alive, we restart the keep
alive timer if any admin or io commands was completed during the kato
period. This prevents a possible starvation of keep alive commands in
the presence of heavy traffic as in such case, we already have a health
indication from the host perspective.

Only set a comp_seen indicator in case the controller supports keep
alive to minimize the overhead for pci controllers.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: cache controller attributes

We get the controller attributes in identify, cache them as we'll need
them for traffic based keep alive support.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add a numa_node field to struct nvme_ctrl

Instead of directly poking into the struct device add a new numa_node
field to struct nvme_ctrl. This allows fabrics drivers where ctrl->dev
is a virtual device to support NUMA affinity as well.

Also expose the field as a sysfs attribute, and populate it for the
RDMA and FC transports.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: warn when finding multi-port subsystems without multipathing enabled

Without CONFIG_NVME_MULTIPATH enabled a multi-port subsystem might
show up as invididual devices and cause problems, warn about it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

blk-mq-tag: change busy_iter_fn to return whether to continue or not

We have this functionality in sbitmap, but we don't export it in
blk-mq for users of the tags busy iteration. This can be useful
for stopping the iteration, if the caller doesn't need to find
more requests.

Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-pci: Add support for P2P memory in requests

For P2P requests, we must use the pci_p2pmem_map_sg() function instead of
the dma_map_sg functions.

With that, we can then indicate PCI_P2P support in the request queue. For
this, we create an NVME_F_PCI_P2P flag which tells the core to set
QUEUE_FLAG_PCI_P2P in the request queue.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>

nvme: take node locality into account when selecting a path

Make current_path an array with an entry for every possible node, and
cache the best path on a per-node basis. Take the node distance into
account when selecting it. This is primarily useful for dual-ported PCIe
devices which are connected to PCIe root ports on different sockets.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>

nvme: register ns_id attributes as default sysfs groups

We should be registering the ns_id attribute as default sysfs
attribute groups, otherwise we have a race condition between
the uevent and the attributes appearing in sysfs.

Suggested-by: Bart van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: use blk API to remap ref tags for IOs with metadata

Also moved the logic of the remapping to the nvme core driver instead
of implementing it in the nvme pci driver. This way all the other nvme
transport drivers will benefit from it (in case they'll implement metadata
support).

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: add ANA support

Add support for Asynchronous Namespace Access as specified in NVMe 1.3
TP 4004. With ANA each namespace attached to a controller belongs to an
ANA group that describes the characteristics of accessing the namespaces
through this controller. In the optimized and non-optimized states
namespaces can be accessed regularly, although in a multi-pathing
environment we should always prefer to access a namespace through a
controller where an optimized relationship exists. Namespaces in
Inaccessible, Permanent-Loss or Change state for a given controller
should not be accessed.

The states are updated through reading the ANA log page, which is read
once during controller initialization, whenever the ANA change notice
AEN is received, or when one of the ANA specific status codes that
signal a state change is received on a command.

The ANA state is kept in the nvme_ns structure, which makes the checks in
the fast path very simple. Updating the ANA state when reading the log
page is also very simple, the only downside is that finding the initial
ANA state when scanning for namespaces is a bit cumbersome.

The gendisk for a ns_head is only registered once a live path for it
exists. Without that the kernel would hang during partition scanning.

Includes fixes and improvements from Hannes Reinecke.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

nvme: remove nvme_req_needs_failover

Now that we just call out to blk_path_error there isn't really any good
reason to not merge it into the only caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

nvme: simplify the API for getting log pages

Merge nvme_get_log and nvme_get_log_ext into a single helper, which takes
a plain nsid instead of the nvme_ns pointer. Also add support for the
log specific field while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

nvme: use hw qid in trace events

We can not match a command to its completion based on the command
id alone. We need the submitting queue identifier to pair with the
completion, so this patch adds that to the trace buffer.

This patch is also collapsing the admin and IO submission traces into a
single one so we don't need to duplicate this and creating unnecessary
code branches: we know if the command is an admin vs IO based on the qid.

And since we're here, the patch fixes code formatting in the area.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
[hch: move the qid helper to nvme.h and made it an inline function]
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: cache struct nvme_ctrl reference to struct nvme_request

We will need to reference the controller in the setup and completion
time for tracing and future traffic based keep alive support.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-pci: limit max IO size and segments to avoid high order allocations

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: Jens Axboe <axboe@kernel.dk>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: remove nvme_reinit_tagset

Unused now that all transports stopped using it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>

nvme: cleanup double shift issue

The problem here is that set_bit() and test_bit() take a bit number so
we should be passing 0 but instead we're passing (1 << 0) which leads to
a double shift. It doesn't cause a runtime bug in the current code
because it's done consistently and we only set that one bit.

I decided to just re-use NVME_AER_NOTICE_NS_CHANGED instead of
introducing a new define for this.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: use the changed namespaces list log to clear ns data changed AENs

Per section 5.2 we need to issue the corresponding log page to clear an
AEN, so for a namespace data changed AEN we need to read the changed
namespace list log. And once we read that log anyway we might as well
use it to optimize the rescan.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: mark nvme_queue_scan static

And move it toward the top of the file to avoid a forward declaration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

nvme: submit AEN event configuration on startup

We should register for AEN events; some law-abiding targets might
not be sending us AENs otherwise.

Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: slight cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

nvme: fix lockdep warning in nvme_mpath_clear_current_path

When running blktest's nvme/005 with a lockdep enabled kernel the test
case fails due to the following lockdep splat in dmesg:

=============================
WARNING: suspicious RCU usage
4.17.0-rc5 #881 Not tainted
-----------------------------
drivers/nvme/host/nvme.h:457 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u32:5/1102:
#0: (ptrval) ((wq_completion)"nvme-wq"){+.+.}, at: process_one_work+0x152/0x5c0
#1: (ptrval) ((work_completion)(&ctrl->scan_work)){+.+.}, at: process_one_work+0x152/0x5c0
#2: (ptrval) (&subsys->lock#2){+.+.}, at: nvme_ns_remove+0x43/0x1c0 [nvme_core]

The only caller of nvme_mpath_clear_current_path() is nvme_ns_remove()
which holds the subsys lock so it's likely a false positive, but when
using rcu_access_pointer(), we're telling rcu and lockdep that we're
only after the pointer falue.

Fixes: 32acab3181c7 ("nvme: implement multipath access to nvme subsystems")
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Suggested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>

nvme: mark the result argument to nvme_complete_async_event volatile

We'll need that in the PCIe driver soon as we'll read it straight off the
CQ.

Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: add quirk to force medium priority for SQ creation

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
81c1cd98351b. This causes various issues on that drive. Add a quirk to
still set MEDIUM priority for that controller.

Fixes: 81c1cd98351b ("nvme/pci: Don't set reserved SQ create flags")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <keith.busch@intel.com>

nvme/multipath: Fix multipath disabled naming collisions

When CONFIG_NVME_MULTIPATH is set, but we're not using nvme to multipath,
namespaces with multiple paths were not creating unique names due to
reusing the same instance number from the namespace's head.

This patch fixes this by falling back to the non-multipath naming method
when the parameter disabled using multipath.

Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: expand nvmf_check_if_ready checks

The nvmf_check_if_ready() checks that were added are very simplistic.
As such, the routine allows a lot of cases to fail ios during windows
of reset or re-connection. In cases where there are not multi-path
options present, the error goes back to the callee - the filesystem
or application. Not good.

The common routine was rewritten and calling syntax slightly expanded
so that per-transport is_ready routines don't need to be present.
The transports now call the routine directly. The routine is now a
fabrics routine rather than an inline function.

The routine now looks at controller state to decide the action to
take. Some states mandate io failure. Others define the condition where
a command can be accepted. When the decision is unclear, a generic
queue-or-reject check is made to look for failfast or multipath ios and
only fails the io if it is so marked. Otherwise, the io will be queued
and wait for the controller state to resolve.

Admin commands issued via ioctl share a live admin queue with commands
from the transport for controller init. The ioctls could be intermixed
with the initialization commands. It's possible for the ioctl cmd to
be issued prior to the controller being enabled. To block this, the
ioctl admin commands need to be distinguished from admin commands used
for controller init. Added a USERCMD nvme_req(req)->rq_flags bit to
reflect this division and set it on ioctls requests. As the
nvmf_check_if_ready() routine is called prior to nvme_setup_cmd(),
ensure that commands allocated by the ioctl path (actually anything
in core.c) preps the nvme_req(req) before starting the io. This will
preserve the USERCMD flag during execution and/or retry.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.e>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: unexport nvme_start_keep_alive

nvme_start_keep_alive() isn't used outside core.c so unexport it and
make it static.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: enforce 64bit offset for nvme_get_log_ext fn

Compiling on 32 bits system produces a warning for the shift width
when shifting 32 bit integer with 64bit integer.

Make sure that offset always is 64bit, and use macros for retrieving
lower and upper bits of the offset.

Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: lightnvm: add late setup of block size and metadata

The nvme driver sets up the size of the nvme namespace in two steps.
First it initializes the device with standard logical block and
metadata sizes, and then sets the correct logical block and metadata
size. Due to the OCSSD 2.0 specification relies on the namespace to
expose these sizes for correct initialization, let it be updated
appropriately on the LightNVM side as well.

Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: make nvme_get_log_ext non-static

Enable the lightnvm integration to use the nvme_get_log_ext()
function.

Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Add .stop_ctrl to nvme ctrl ops

For consistancy reasons, any fabric-specific works
(e.g error recovery/reconnect) should be canceled in
nvme_stop_ctrl, as for all other NVMe pending works
(e.g. scan, keep alive).

The patch aims to simplify the logic of the code, as
we now only rely on a vague demand from any fabric
to flush its private workqueues at the beginning of
.delete_ctrl op.

Signed-off-by: Nitzan Carmi <nitzanc@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: change namespaces_mutext to namespaces_rwsem

namespaces_mutext is used to synchronize the operations on ctrl
namespaces list. Most of the time, it is a read operation.

On the other hand, there are many interfaces in nvme core that
need this lock, such as nvme_wait_freeze, and even more interfaces
will be added. If we use mutex here, circular dependency could be
introduced easily. For example:
context A context B
nvme_xxx nvme_xxx
hold namespaces_mutext require namespaces_mutext
sync context B

So it is better to change it from mutex to rwsem.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: Add fault injection feature

Linux's fault injection framework provides a systematic way to support
error injection via debugfs in the /sys/kernel/debug directory. This
patch uses the framework to add error injection to NVMe driver. The
fault injection source code is stored in a separate file and only linked
if CONFIG_FAULT_INJECTION_DEBUG_FS kernel config is selected.

Once the error injection is enabled, NVME_SC_INVALID_OPCODE with no
retry will be injected into the nvme_end_request. Users can change
the default status code and no retry flag via debufs. Following example
shows how to enable and inject an error. For more examples, refer to
Documentation/fault-injection/nvme-fault-injection.txt

How to enable nvme fault injection:

First, enable CONFIG_FAULT_INJECTION_DEBUG_FS kernel config,
recompile the kernel. After booting up the kernel, do the
following.

How to inject an error:

mount /dev/nvme0n1 /mnt
echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times
echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability
cp a.file /mnt

Expected Result:

cp: cannot stat ‘/mnt/a.file’: Input/output error

Message from dmesg:

FAULT_INJECTION: forcing a failure.
name fault_inject, interval 1, probability 100, space 0, times 1
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc8+ #2
Hardware name: innotek GmbH VirtualBox/VirtualBox,
BIOS VirtualBox 12/01/2006
Call Trace:
<IRQ>
dump_stack+0x5c/0x7d
should_fail+0x148/0x170
nvme_should_fail+0x2f/0x50 [nvme_core]
nvme_process_cq+0xe7/0x1d0 [nvme]
nvme_irq+0x1e/0x40 [nvme]
__handle_irq_event_percpu+0x3a/0x190
handle_irq_event_percpu+0x30/0x70
handle_irq_event+0x36/0x60
handle_fasteoi_irq+0x78/0x120
handle_irq+0xa7/0x130
? tick_irq_enter+0xa8/0xc0
do_IRQ+0x43/0xc0
common_interrupt+0xa2/0xa2
</IRQ>
RIP: 0010:native_safe_halt+0x2/0x10
RSP: 0018:ffffffff82003e90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
RAX: ffffffff817a10c0 RBX: ffffffff82012480 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 000000008e38ce64 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82012480
R13: ffffffff82012480 R14: 0000000000000000 R15: 0000000000000000
? __sched_text_end+0x4/0x4
default_idle+0x18/0xf0
do_idle+0x150/0x1d0
cpu_startup_entry+0x6f/0x80
start_kernel+0x4c4/0x4e4
? set_init_arg+0x55/0x55
secondary_startup_64+0xa5/0xb0
print_req_error: I/O error, dev nvme0n1, sector 9240
EXT4-fs error (device nvme0n1): ext4_find_entry:1436:
inode #2: comm cp: reading directory lblock 0

Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Reviewed-by: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Signed-off-by: Karl Volz <karl.volz@oracle.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Revert "nvme: create 'slaves' and 'holders' entries for hidden controllers"

This reverts commit e9a48034d7d1318ece7d4a235838a86c94db9d68.

The slaves and holders link for the hidden gendisks confuse lsblk so that
it errors out on, or doesn't report the nvme multipath devices. Given
that we don't need holder relationships for something that can't even be
directly accessed we should just stop creating those links.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Potnuri Bharat Teja <bharat@chelsio.com>
Cc: stable@vger.kernel.org
Signed-off-by: Keith Busch <keith.busch@intel.com>

nvme: Don't use a stack buffer for keep-alive command

In nvme_keep_alive() we pass a request with a pointer to an NVMe command on
the stack into blk_execute_rq_nowait(). However, the block layer doesn't
guarantee that the request is fully queued before blk_execute_rq_nowait()
returns. If not, and the request is queued after nvme_keep_alive() returns,
then we'll end up using stack memory that might have been overwritten to
form the NVMe command we pass to hardware.

Fix this by keeping a special command struct in the nvme_ctrl struct right
next to the delayed work struct used for keep-alives.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: rename NVME_CTRL_RECONNECTING state to NVME_CTRL_CONNECTING

In pci transport, this state is used to mark the initialization
process. This should be also used in other transports as well.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme: host delete_work and reset_work on separate workqueues

We need to ensure that delete_work will be hosted on a different
workqueue than all the works we flush or cancel from it.
Otherwise we may hit a circular dependency warning [1].

Also, given that delete_work flushes reset_work, host reset_work
on nvme_reset_wq and delete_work on nvme_delete_wq. In addition,
fix the flushing in the individual drivers to flush nvme_delete_wq
when draining queued deletes.

[1]:
[ 178.491942] =============================================
[ 178.492718] [ INFO: possible recursive locking detected ]
[ 178.493495] 4.9.0-rc4-c844263313a8-lb #3 Tainted: G OE
[ 178.494382] ---------------------------------------------
[ 178.495160] kworker/5:1/135 is trying to acquire lock:
[ 178.495894] (
[ 178.496120] "nvme-wq"
[ 178.496471] ){++++.+}
[ 178.496599] , at:
[ 178.496921] [<ffffffffa70ac206>] flush_work+0x1a6/0x2d0
[ 178.497670]
but task is already holding lock:
[ 178.498499] (
[ 178.498724] "nvme-wq"
[ 178.499074] ){++++.+}
[ 178.499202] , at:
[ 178.499520] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0
[ 178.500343]
other info that might help us debug this:
[ 178.501269] Possible unsafe locking scenario:

[ 178.502113] CPU0
[ 178.502472] ----
[ 178.502829] lock(
[ 178.503115] "nvme-wq"
[ 178.503467] );
[ 178.503716] lock(
[ 178.504001] "nvme-wq"
[ 178.504353] );
[ 178.504601]
*** DEADLOCK ***

[ 178.505441] May be due to missing lock nesting notation

[ 178.506453] 2 locks held by kworker/5:1/135:
[ 178.507068] #0:
[ 178.507330] (
[ 178.507598] "nvme-wq"
[ 178.507726] ){++++.+}
[ 178.508079] , at:
[ 178.508173] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0
[ 178.509004] #1:
[ 178.509265] (
[ 178.509532] (&ctrl->delete_work)
[ 178.509795] ){+.+.+.}
[ 178.510145] , at:
[ 178.510239] [<ffffffffa70ad6c2>] process_one_work+0x162/0x6a0
[ 178.511070]
stack backtrace:
:
[ 178.511693] CPU: 5 PID: 135 Comm: kworker/5:1 Tainted: G OE 4.9.0-rc4-c844263313a8-lb #3
[ 178.512974] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014
[ 178.514247] Workqueue: nvme-wq nvme_del_ctrl_work [nvme_tcp]
[ 178.515071] ffffc2668175bae0 ffffffffa7450823 ffffffffa88abd80 ffffffffa88abd80
[ 178.516195] ffffc2668175bb98 ffffffffa70eb012 ffffffffa8d8d90d ffff9c472e9ea700
[ 178.517318] ffff9c472e9ea700 ffff9c4700000000 ffff9c4700007200 ab83be61bec0d50e
[ 178.518443] Call Trace:
[ 178.518807] [<ffffffffa7450823>] dump_stack+0x85/0xc2
[ 178.519542] [<ffffffffa70eb012>] __lock_acquire+0x17d2/0x18f0
[ 178.520377] [<ffffffffa75839a7>] ? serial8250_console_putchar+0x27/0x30
[ 178.521330] [<ffffffffa7583980>] ? wait_for_xmitr+0xa0/0xa0
[ 178.522174] [<ffffffffa70ac1eb>] ? flush_work+0x18b/0x2d0
[ 178.522975] [<ffffffffa70eb7cb>] lock_acquire+0x11b/0x220
[ 178.523753] [<ffffffffa70ac206>] ? flush_work+0x1a6/0x2d0
[ 178.524535] [<ffffffffa70ac229>] flush_work+0x1c9/0x2d0
[ 178.525291] [<ffffffffa70ac206>] ? flush_work+0x1a6/0x2d0
[ 178.526077] [<ffffffffa70a9cf0>] ? flush_workqueue_prep_pwqs+0x220/0x220
[ 178.527040] [<ffffffffa70ae7cf>] __cancel_work_timer+0x10f/0x1d0
[ 178.527907] [<ffffffffa70fecb9>] ? vprintk_default+0x29/0x40
[ 178.528726] [<ffffffffa71cb507>] ? printk+0x48/0x50
[ 178.529434] [<ffffffffa70ae8c3>] cancel_delayed_work_sync+0x13/0x20
[ 178.530381] [<ffffffffc042100b>] nvme_stop_ctrl+0x5b/0x70 [nvme_core]
[ 178.531314] [<ffffffffc0403dcc>] nvme_del_ctrl_work+0x2c/0x50 [nvme_tcp]
[ 178.532271] [<ffffffffa70ad741>] process_one_work+0x1e1/0x6a0
[ 178.533101] [<ffffffffa70ad6c2>] ? process_one_work+0x162/0x6a0
[ 178.533954] [<ffffffffa70adc4e>] worker_thread+0x4e/0x490
[ 178.534735] [<ffffffffa70adc00>] ? process_one_work+0x6a0/0x6a0
[ 178.535588] [<ffffffffa70adc00>] ? process_one_work+0x6a0/0x6a0
[ 178.536441] [<ffffffffa70b48cf>] kthread+0xff/0x120
[ 178.537149] [<ffffffffa70b47d0>] ? kthread_park+0x60/0x60
[ 178.538094] [<ffffffffa70b47d0>] ? kthread_park+0x60/0x60
[ 178.538900] [<ffffffffa78e332a>] ret_from_fork+0x2a/0x40

Signed-off-by: Roy Shterman <roys@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-pci: serialize pci resets

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme/multipath: Consult blk_status_t for failover

This removes nvme multipath's specific status decoding to see if failover
is needed, using the generic blk_status_t that was decoded earlier. This
abstraction from the raw NVMe status means all status decoding exists
in one place.

Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
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@kernel.dk>

nvme-pci: fix NULL pointer reference in nvme_alloc_ns

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: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-mpath: fix last path removal during traffic

In case our last path is removed during traffic, we can end up requeueing
the bio(s) but never schedule the actual requeue work as upper layers
still have open handles on the mpath device node.

Fix this by scheduling requeue work if the namespace being removed is
the last path in the ns_head path list.

Fixes: 32acab3181c7 ("nvme: implement multipath access to nvme subsystems")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme-pci: add quirk for delay before CHK RDY for WDC SN200

And increase the existing delay to cover this device as well.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Lien <jeff.lien@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme: create 'slaves' and 'holders' entries for hidden controllers

When creating nvme multipath devices we should populate the 'slaves' and
'holders' directorys properly to aid userspace topology detection.

Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: split from a larger patch, compile fix for CONFIG_NVME_MULTIPATH=n]
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: also expose the namespace identification sysfs files for mpath nodes

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: implement multipath access to nvme subsystems

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: track shared namespaces

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: introduce a nvme_ns_ids structure

This allows us to manage the various uniqueue namespace identifiers
together instead needing various variables and arguments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: track subsystems

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, nvme: Introduce blk_mq_req_flags_t

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: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Oleksandr 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: Jens Axboe <axboe@kernel.dk>

nvme: send uevent for some asynchronous events

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: Keith Busch <keith.busch@intel.com>
Reviewed-by: Guan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: unexport starting async event work

Async event work is for core use only and should not be called directly
from drivers.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Guan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove handling of multiple AEN requests

The driver can handle tracking only one AEN request, so this patch
removes handling for multiple ones.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: centralize AEN defines

All the transports were unnecessarilly duplicating the AEN request
accounting. This patch defines everything in one place.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Guan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: check admin passthru command effects

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: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: move controller deletion to common code

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>