This patch updates RSCN receive processing to check for the remote
port being an NVME port, and if so, invoke the nvme_fc callback to
rescan the remote port.  The rescan will generate a discovery udev
event.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NArun Easi <aeasi@marvell.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch avoids that the following compiler warning is reported with
CONFIG_NVME_FC=n:

drivers/scsi/lpfc/lpfc_nvme.c:2140:1: warning: 'lpfc_nvme_lport_unreg_wait' defined but not used [-Wunused-function]
 lpfc_nvme_lport_unreg_wait(struct lpfc_vport *vport,
 ^~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 3999df75 ("scsi: lpfc: Declare local functions static")
Cc: James Smart <james.smart@broadcom.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Reviewed-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>

This patch avoids that a kernel warning appears when smp_processor_id() is
called with preempt debugging enabled.

Cc: James Smart <james.smart@broadcom.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch avoids that the compiler warns about missing fall-through
annotation when building with W=1.

Cc: James Smart <james.smart@broadcom.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch avoids that the compiler complains about missing declarations
when building with W=1.

Cc: James Smart <james.smart@broadcom.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

clang -Wuninitialized incorrectly sees a variable being used without
initialization:

drivers/scsi/lpfc/lpfc_nvme.c:2102:37: error: variable 'localport' is uninitialized when used here
      [-Werror,-Wuninitialized]
                lport = (struct lpfc_nvme_lport *)localport->private;
                                                  ^~~~~~~~~
drivers/scsi/lpfc/lpfc_nvme.c:2059:38: note: initialize the variable 'localport' to silence this warning
        struct nvme_fc_local_port *localport;
                                            ^
                                             = NULL
1 error generated.

This is clearly in dead code, as the condition leading up to it is always
false when CONFIG_NVME_FC is disabled, and the variable is always
initialized when nvme_fc_register_localport() got called successfully.

Change the preprocessor conditional to the equivalent C construct, which
makes the code more readable and gets rid of the warning.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Update the 6072 log message string to print the whole 32 bits of the
extended status.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The newly introduced 'cpu' variable is only used inside of an optional
block, so we get a warning without CONFIG_SCSI_LPFC_DEBUG_FS:

drivers/scsi/lpfc/lpfc_nvme.c: In function 'lpfc_nvme_io_cmd_wqe_cmpl':
drivers/scsi/lpfc/lpfc_nvme.c:968:30: error: unused variable 'cpu' [-Werror=unused-variable]
  uint32_t code, status, idx, cpu;

Move the declaration into the same block to avoid the warning.

Fixes: 63df6d63 ("scsi: lpfc: Adapt cpucheck debugfs logic to Hardware Queues")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For files modified as part of 12.2.0.0 patches, update copyright to 2019
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

A scsi host lock is taken on every io completion to check whether the abort
handler is waiting on the io completion. This is an expensive lock to take
on all completion when rarely in an abort condition.

Replace scsi host lock with command-specific lock. Synchronize completion
and abort paths by new cmd lock. Ensure all flag changing and nulling of
context pointers taken under lock.  When adding lock to task management
abort, realized it was missing other synchronization locks. Added that
synchronization to match normal paths.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

So far MSIX vector allocation assumed it would be 1:1 with hardware
queues. However, there are several reasons why fewer MSIX vectors may be
allocated than hardware queues such as the platform being out of vectors or
adapter limits being less than cpu count.

This patch reworks the MSIX/EQ relationships with the per-cpu hardware
queues so they can function independently. MSIX vectors will be equitably
split been cpu sockets/cores and then the per-cpu hardware queues will be
mapped to the vectors most efficient for them.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Default behavior is to use the information from the upper IO stacks to
select the hardware queue to use for IO submission.  Which typically has
good cpu affinity.

However, the driver, when used on some variants of the upstream kernel, has
found queuing information to be suboptimal for FCP or IO completion locked
on particular cpus.

For command submission situations, the lpfc_fcp_io_sched module parameter
can be set to specify a hardware queue selection policy that overrides the
os stack information.

For IO completion situations, rather than queing cq processing based on the
cpu servicing the interrupting event, schedule the cq processing on the cpu
associated with the hardware queue's cq.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The XRI get/put lists were partitioned per hardware queue. However, the
adapter rarely had sufficient resources to give a large number of resources
per queue. As such, it became common for a cpu to encounter a lack of XRI
resource and request the upper io stack to retry after returning a BUSY
condition. This occurred even though other cpus were idle and not using
their resources.

Create as efficient a scheme as possible to move resources to the cpus that
need them. Each cpu maintains a small private pool which it allocates from
for io. There is a watermark that the cpu attempts to keep in the private
pool.  The private pool, when empty, pulls from a global pool from the
cpu. When the cpu's global pool is empty it will pull from other cpu's
global pool. As there many cpu global pools (1 per cpu or hardware queue
count) and as each cpu selects what cpu to pull from at different rates and
at different times, it creates a radomizing effect that minimizes the
number of cpu's that will contend with each other when the steal XRI's from
another cpu's global pool.

On io completion, a cpu will push the XRI back on to its private pool.  A
watermark level is maintained for the private pool such that when it is
exceeded it will move XRI's to the CPU global pool so that other cpu's may
allocate them.

On NVME, as heartbeat commands are critical to get placed on the wire, a
single expedite pool is maintained. When a heartbeat is to be sent, it will
allocate an XRI from the expedite pool rather than the normal cpu
private/global pools. On any io completion, if a reduction in the expedite
pools is seen, it will be replenished before the XRI is placed on the cpu
private pool.

Statistics are added to aid understanding the XRI levels on each cpu and
their behaviors.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

SLI4 nvme functions are passing the SLI3 ring number when posting wqe to
hardware. This should be indicating the hardware queue to use, not the ring
number.

Replace ring number with the hardware queue that should be used.

Note: SCSI avoided this issue as it utilized an older lfpc_issue_iocb
routine that properly adapts.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Many io statistics were being sampled and saved using adapter-based data
structures. This was creating a lot of contention and cache thrashing in
the I/O path.

Move the statistics to the hardware queue data structures.  Given the
per-queue data structures, use of atomic types is lessened.

Add new sysfs and debugfs stat routines to collate the per hardware queue
values and report at an adapter level.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Similar to the io execution path that reports cpu context information, the
debugfs routines for cpu information needs to be aligned with new hardware
queue implementation.

Convert debugfs cnd nvme cpucheck statistics to report information per
Hardware Queue.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Once the IO buff allocations were made shared, there was a single XRI
buffer list shared by all hardware queues.  A single list isn't great for
performance when shared across the per-cpu hardware queues.

Create a separate XRI IO buffer get/put list for each Hardware Queue.  As
SGLs and associated IO buffers get allocated/posted to the firmware; round
robin their assignment across all available hardware Queues so that there
is an equitable assignment.

Modify SCSI and NVME IO submit code paths to use the Hardware Queue logic
for XRI allocation.

Add a debugfs interface to display hardware queue statistics

Added new empty_io_bufs counter to track if a cpu runs out of XRIs.

Replace common_ variables/names with io_ to make meanings clearer.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently, both nvme and fcp each have their own concept of an io_channel,
which is a combination wq/cq and associated msix.  Different cpus would
share an io_channel.

The driver is now moving to per-cpu wq/cq pairs and msix vectors.  The
driver will still use separate wq/cq pairs per protocol on each cpu, but
the protocols will share the msix vector.

Given the elimination of the nvme and fcp io channels, the module
parameters will be removed.  A new parameter, lpfc_hdw_queue is added which
allows the wq/cq pair allocation per cpu to be overridden and allocated to
lesser value. If lpfc_hdw_queue is zero, the number of pairs allocated will
be based on the number of cpus. If non-zero, the parameter specifies the
number of queues to allocate. At this time, the maximum non-zero value is
64.

To manage this new paradigm, a new hardware queue structure is created to
track queue activity and relationships.

As MSIX vector allocation must be known before setting up the
relationships, msix allocation now occurs before queue datastructures are
allocated. If the number of vectors allocated is less than the desired
hardware queues, the hardware queue counts will be reduced to the number of
vectors
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently, both NVME and SCSI get their IO buffers from separate
pools. XRI's are associated 1:1 with IO buffers, so XRI's are also split
between protocols.

Eliminate the independent pools and use a single pool. Each buffer
structure now has a common section and a protocol section. Per protocol
routines for SGL initialization are removed and replaced by common
routines. Initialization of the buffers is only done on the common area.
All other fields, which are protocol specific, are initialized when the
buffer is allocated for use in the per-protocol allocation routine.

In the past, the SCSI side allocated IO buffers as part of slave_alloc
calls until the maximum XRIs for SCSI was reached. As all XRIs are now
common and may be used for either protocol, allocation for everything is
done as part of adapter initialization and the scsi side has no action in
slave alloc.

As XRI's are no longer split, the lpfc_xri_split module parameter is
removed.

Adapters based on SLI3 will continue to use the older scsi_buf_list_get/put
routines.  All SLI4 adapters utilize the new IO buffer scheme
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

lpfc_nvme_prep_io_cmd() checks for null pnode, but caller
lpfc_nvme_fcp_io_submit() has already ensured it's non-null.

Remove the pnode null check.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

An hba-wide lock is taken in the nvme io completion routine. The lock
covers null'ing of the nrport pointer in the cmd structure.

The nrport member isn't necessary. After extracting the pointer from the
command, the pointer was dereferenced to get the fc discovery node
pointer. But the fc discovery node pointer is alrady in the command
structure so the dereferrence was unnecessary.

Eliminated the nrport structure member and its use, which also eliminates
the port-wide lock.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We cannot wait on a completion object in the lpfc_nvme_lport structure in
the _destroy_localport() code path because the NVMe/fc transport will free
that structure immediately after the .localport_delete() callback.  This
results in a use-after-free, and a hang if slub_debug=FZPU is enabled.

Fix this by putting the completion on the stack.
Signed-off-by: NEwan D. Milne <emilne@redhat.com>
Acked-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Driver is setting bits in word 10 of the SLI4 ABORT WQE (the wqid).  The
field was a carry over from a prior SLI revision. The field does not exist
in SLI4, and the action may result in an overlap with future definition of
the WQE.

Remove the setting of WQID in the ABORT WQE.

Also cleaned up WQE field settings - initialize to zero, don't bother to
set fields to zero.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The driver currently uses the ndlp to get the local rport which is then used
to get the nvme transport remoteport pointer. There can be cases where a stale
remoteport pointer is obtained as synchronization isn't done through the
different dereferences.

Correct by using locks to synchronize the dereferences.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/scsi/lpfc/lpfc_nvme.c: In function 'lpfc_new_nvme_buf':
drivers/scsi/lpfc/lpfc_nvme.c:2238:24: warning:
 variable 'sgl_size' set but not used [-Wunused-but-set-variable]
  int bcnt, num_posted, sgl_size;
                        ^
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Message 6408 is displayed for each entry in an array, but the cpu and queue
numbers were incorrect for the entry.  Message 6001 includes an extraneous
character.

Resolve both issues
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The driver allocates a sg list per io struture based on a fixed maximum
size. When it registers with the protocol transports and indicates the max sg
list size it supports, the driver manipulates the fixed value to report a
lesser amount so that it has reserved space for sg elements that are used for
DIF.

The driver initialization path sets the cfg_sg_seg_cnt field to the
manipulated value for scsi. NVME initialization ran afterward and capped it's
maximum by the manipulated value for SCSI. This erroneously made NVME report
the SCSI-reduce-for-DIF value that reduced the max io size for nvme and wasted
sg elements.

Rework the driver so that cfg_sg_seg_cnt becomes the overall maximum size and
allow the max size to be tunable.  A separate (new) scsi sg count is then
setup with the scsi-modified reduced value. NVME then initializes based off
the overall maximum.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Performance is affected when target queue depth is tracked.  An atomic
counter is incremented on the submission path which competes with it being
decremented on the completion path.  In addition, multiple CPUs can
simultaniously be manipulating this counter for the same ndlp.

Reduce the overhead by only performing the target increment/decrement when
the target queue depth is less than the overall adapter depth, thus is
actually meaningful.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

During remote port loss fault testing, the driver crashed with the
following trace:

general protection fault: 0000 [#1] SMP
RIP: ... lpfc_nvme_register_port+0x250/0x480 [lpfc]
Call Trace:
 lpfc_nlp_state_cleanup+0x1b3/0x7a0 [lpfc]
 lpfc_nlp_set_state+0xa6/0x1d0 [lpfc]
 lpfc_cmpl_prli_prli_issue+0x213/0x440
 lpfc_disc_state_machine+0x7e/0x1e0 [lpfc]
 lpfc_cmpl_els_prli+0x18a/0x200 [lpfc]
 lpfc_sli_sp_handle_rspiocb+0x3b5/0x6f0 [lpfc]
 lpfc_sli_handle_slow_ring_event_s4+0x161/0x240 [lpfc]
 lpfc_work_done+0x948/0x14c0 [lpfc]
 lpfc_do_work+0x16f/0x180 [lpfc]
 kthread+0xc9/0xe0
 ret_from_fork+0x55/0x80

After registering a new remoteport, the driver is pulling an ndlp pointer
from the lpfc rport associated with the private area of a newly registered
remoteport. The private area is uninitialized, so it's garbage.

Correct by pulling the the lpfc rport pointer from the entering ndlp point,
then ndlp value from at rport. Note the entering ndlp may be replacing by
the rport->ndlp due to an address change swap.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The PBDE optimizations aren't supported in all firmware revs.

Make optimizations configurable in case there's a side effect on old
firmware.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

System crashes when the lpfc module is unloaded after making the port
offline

The nvme queue pointers were freed during port offline, but were later
accessed in pci remove path.

Validate the pointers in pci remove path before accessing them.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

modprobe -r lpfc produces the following:

Call Trace:
 __blk_mq_run_hw_queue+0xa2/0xb0
 __blk_mq_delay_run_hw_queue+0x9d/0xb0
 ? blk_mq_hctx_has_pending+0x32/0x80
 blk_mq_run_hw_queue+0x50/0xd0
 blk_mq_sched_insert_request+0x110/0x1b0
 blk_execute_rq_nowait+0x76/0x180
 nvme_keep_alive_work+0x8a/0xd0 [nvme_core]
 process_one_work+0x17f/0x440
 worker_thread+0x126/0x3c0
 ? manage_workers.isra.24+0x2a0/0x2a0
 kthread+0xd1/0xe0
 ? insert_kthread_work+0x40/0x40
 ret_from_fork_nospec_begin+0x21/0x21
 ? insert_kthread_work+0x40/0x40

However, rmmod lpfc would run correctly.

When an nvme remoteport is unregistered with the host nvme transport, it
needs to set the remoteport->dev_loss_tmo value 0 to indicate an immediate
termination of device loss and prevent any further keep alives to that
rport.  The driver was never setting dev_loss_tmo causing the nvme
transport to continue to send the keep alive.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Under large configurations, the driver would start to log message 6065 -
NVME out of buffers (exchanges).

The driver is using the ndlp cmd_qdepth value when determining the max
outstanding ios for an adapter. This value, by default, is set to 65536,
which exceeds the maximum exchange counts supported on an adapter. The ndlp
cmd_qdepth has no relevance and outstanding io count should be capped at
the max exchange count with IO requests beyond that level getting bounced
back with an EBUSY status so that they are retried by the block layer.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix small formatting and wording nits in Broadcom copyright header
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix up log messages and add an fcp error stat counter in the IO submit
code path to make diagnosing problems easier
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

I/O submission paths in the lpfc nvme path are rejecting the io with an
error code that reflects back to the callee as a hard io failure. Many
of these conditions are transient and would likely resolve if retried.

Correct by returning -EBUSY, which the FC transport triggers off of to
return busy status codes to the blk-mq layer.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Points referencing local port structures didn't accommodate cases where
the localport may not be registered yet.

Add NULL pointer checks to logic.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

On tests adding and removing a remote port, calls to nvme_info would
eventually show fewer target ports discovered than were present in the
san. Additionally, the following error messages were seen:

  6031 RemotePort Registration failed err: -116, DID x471301

There is a race condition that exists between the driver and the nvme
transport on remote port unregister vs the confirmed deletion. It's
possible that the driver may rediscover the remote port and reregister
the remote port before a prior unregister delete callback was made (as
it rebinded to the prior remoteport structure). However, the driver was
coded to expect the callback before seeing the remote port again thus a
new registration. The logic results in the driver having an invalid
remoteport pointer set.

Correct by tracking when waiting for the delete callback. In cases where
the ndlp remoteport pointer is updated, it is only cleared when the wait
has not been superceded by a prior registration.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

During target-side port faults, the driver would not recover all target
port logins. This resulted in a loss of nvme device discovery.

The driver is coded to wait for all GID_FT requests to complete before
restarting discovery. A fault is seen where the outstanding GIT_FT
counts are not properly decremented, thus discovery would never
start. Another fault was found in the clearing of the gidft_inp counter
that would be skipped in this condition. And a third fault found with
lpfc_nvme_register_port that would remove a reverence on the ndlp which
then allows a node swap on a port address change to prematurely remove
the reference and release the ndlp.

The following changes are made:

 - Correct the decrementing of the outstanding GID_FT counters.

 - In RSCN handling, no longer zero the counter before calling to issue
   another GID_FT.

 - No longer remove the reference on the dlp when the ndlp->nrport value
   is not yet null.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>