nvmet: add tracing of zns commands

Add nvme_cmd_zone_append, nvme_cmd_zone_mgmt_send and
nvme_cmd_zone_mgmt_recv parse to nvme target tracing.

Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvmet: add tracing of authentication commands

Add nvme_fabrics_type_auth_send and nvme_fabrics_type_auth_receive
to the nvme target's tracing facility.

Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

nvmet-trace: avoid dereferencing pointer too early

The first command issued from the host to the target is the fabrics
connect command. At this point, neither the target queue nor the
controller have been allocated. But we already try to trace this command
in nvmet_req_init.

Reported by KASAN.

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

nvmet: add set feature tracing support

A nvme connect command produces following trace from the target side.

Before:
kworker/0:1H-56 [000] .... 9012.155139: nvmet_req_init: nvmet1: qid=0, cmdid=16, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_set_features, cdw10=07 00 00 00 07 00 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00)
kworker/0:1H-56 [000] .... 9012.872272: nvmet_req_init: nvmet1: qid=0, cmdid=13, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_set_features, cdw10=0b 00 00 00 00 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00)

cmdline:/sys/kernel/debug/tracing# cat trace | grep feature
kworker/0:1H-56 [000] .... 203.493914: nvmet_req_init: nvmet1: qid=0, cmdid=29, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_set_features, fid=0x7, sv=0x0, cdw11=0x70007)
kworker/0:1H-56 [000] .... 204.197079: nvmet_req_init: nvmet1: qid=0, cmdid=29, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_set_features, fid=0xb, sv=0x0, cdw11=0x900)

Using ',' to separate different field like others in
nvmet_trace_admin_get_features.

Signed-off-by: Hou Pu <houpu.main@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvmet: trace: parse Get LBA Status command in detail

Four different fields are in CDWs of Get LBA Status command which means
it would be great if we can see in detail when tracing in target side
also.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

nvme-trace: fix spelling mistake "spcecific" -> "specific"

There are two spelling mistakes in trace_seq_printf messages, fix these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvmet: introduce target-side trace

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

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

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

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

Example:
echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_init/enable
echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_complete/enable
cat /sys/kernel/debug/tracing/trace

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
[hch: fixed the symbol namespace and a an endianess conversion]
Signed-off-by: Christoph Hellwig <hch@lst.de>