Driver added mechanism to move ABTS/PUREX/RIDA mailbox to
ATIO queue as part of commit id 41dc529a
("qla2xxx: Improve RSCN handling in driver").

This patch adds a check to only allow ABTS/PURX/RIDA
to be moved to ATIO Queue for ISP83XX and ISP27XX.

Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

when driver is loaded with Multi Queue enabled, it was noticed that
there was one less queue pair created.

Following message would indicate this:

"No resources to create additional q pair."

The result of one less queue pair means that system can crash, if the
block mq layer thinks there is an extra hardware queue available, and
the driver will use a NULL ptr qpair in that instance.

Following stack trace is seen in one of the crash:

irq_create_affinity_masks+0x98/0x530
irq_create_affinity_masks+0x98/0x530
__pci_enable_msix+0x321/0x4e0
mutex_lock+0x12/0x40
pci_alloc_irq_vectors_affinity+0xb5/0x140
qla24xx_enable_msix+0x79/0x530 [qla2xxx]
qla2x00_request_irqs+0x61/0x2d0 [qla2xxx]
qla2x00_probe_one+0xc73/0x2390 [qla2xxx]
ida_simple_get+0x98/0x100
kernfs_next_descendant_post+0x40/0x50
local_pci_probe+0x45/0xa0
pci_device_probe+0xfc/0x140
driver_probe_device+0x2c5/0x470
__driver_attach+0xdd/0xe0
driver_probe_device+0x470/0x470
bus_for_each_dev+0x6c/0xc0
driver_attach+0x1e/0x20
bus_add_driver+0x45/0x270
driver_register+0x60/0xe0
__pci_register_driver+0x4c/0x50
qla2x00_module_init+0x1ce/0x21e [qla2xxx]

Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: NSawan Chandak <sawan.chandak@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NMilan P Gandhi <mgandhi@redhat.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Current driver wait for FW to be in the ready state before
processing in-coming commands. For Arbitrated Loop or
Point-to- Point (not switch), FW Ready state can take a while.
FW will transition to ready state after all Nports have been
logged in. In the mean time, certain initiators have completed
the login and starts IO. Driver needs to start processing all
queues if FW is already started.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

For target mode, when new scsi command arrive, driver first performs
a look up of the SCSI Host. The current look up method is based on
the ALPA portion of the NPort ID. For Cisco switch, the ALPA can
not be used as the index. Instead, the new search method is based
on the full value of the Nport_ID via btree lib.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The Mailbox interface is currently over subscribed. We like
to reserve the Mailbox interface for the chip managment and
link initialization. Any non essential Mailbox command will
be routed through the IOCB interface. The IOCB interface is
able to absorb more commands.

Following commands are being routed through IOCB interface

- Get ID List (007Ch)
- Get Port DB (0064h)
- Get Link Priv Stats (006Dh)
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If the remote port have started the login process, then the
PLOGI and PRLI should be back to back. Driver will allow
the remote port to complete the process. For the case where
the remote port decide to back off from sending PRLI, this
local port sets an expiration timer for the PRLI. Once the
expiration time passes, the relogin retry logic is allowed
to go through and perform login with the remote port.
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Cc: <stable@vger.kernel.org>
Signed-off-by: NJoe Carnuccio <joe.carnuccio@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the following warning reported by the "smatch" static checker:

drivers/scsi/qla2xxx/qla_init.c:3910 qla2x00_alloc_fcport()
warn: use 'flags' here instead of GFP_XXX?
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch simplifies SRB structure usage in driver.

- Simplify sp->done() and sp->free() interfaces.
- Remove sp->fcport->vha to use vha pointer from sp.
- Use sp->vha context in qla2x00_rel_sp().
Signed-off-by: NJoe Carnuccio <joe.carnuccio@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Current code blindly does State Change Registration when
the link is up. Move SCR behind fabric scan, so that arbitrated
loop scan would not get erroneous error message.

Some of the other improvements are as follows

- Add session deletion for TPRLO and send acknowledgment for TPRLO.
- Enable FW option to move ABTS, RIDA & PUREX from RSPQ to ATIOQ.
- Save NPort ID early in link init.
- Move ABTS & RIDA to ATIOQ helps in keeping command ordering and
  link up sequence ordering.
- Save Nport ID and update VP map so that SCSI CMD/ATIO won't be dropped.
- fcport alloc does the initializes memory to zero. Remove memset to
  zero since It might corrupt link list.
- Turn off Registration for State Change MB in loop mode.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Add switch to allow both Initiator Mode & Target
mode to operate at the same time.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Currently code performs a full scan of the fabric for
every RSCN. Its an expensive process in a noisy large SAN.

This patch optimizes expensive fabric discovery process by
scanning switch for the affected port when RSCN is received.

Currently Initiator Mode code makes login/logout decision without
knowledge of target mode. This causes driver and firmware to go
out-of-sync. This framework synchronizes both initiator mode
personality and target mode personality in making login/logout
decision.

This patch adds following capabilities in the driver

- Send Notification Acknowledgement asynchronously.
- Update session/fcport state asynchronously.
- Create a session or fcport struct asynchronously.
- Send GNL asynchronously. The command will ask FW to
  provide a list of FC Port entries FW knows about.
- Send GPDB asynchronously. The command will ask FW to
  provide detail data of an FC Port FW knows about or
  perform ADISC to verify the state of the session.
- Send GPNID asynchronously. The command will ask switch
  to provide WWPN for provided NPort ID.
- Send GPSC asynchronously. The command will ask switch
  to provide registered port speed for provided WWPN.
- Send GIDPN asynchronously. The command will ask the
  switch to provide Nport ID for provided WWPN.
- In driver unload path, schedule all session for deletion
  and wait for deletion to complete before allowing driver
  unload to proceed.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
[ bvanassche: fixed spelling in patch description ]
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Current code merges qla_tgt_sess and fc_port structure
into single fc_port structure representing same I-T nexus.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
[ bvanassche: fixed spelling of patch description ]
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Soft reset and Risc reset should take 100uS to complete.
This change pad the timeout up to 400uS, which should be
plenty.
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

- Fix race condition between dpc_thread accessing Multiqueue resources
  and qla2x00_remove_one thread trying to free resource.
- Fix out of order free for Multiqueue resources. Also, Multiqueue
  interrupts needs a workqueue. Interrupt needed to stop before
  the wq can be destroyed.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NQuinn Tran <quinn.tran@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Replaced existing multiple queue functionality with framework
that allows for the creation of pairs of request and response queues,
either at start of day or dynamically.

Queue pair creation depend on module parameter "ql2xmqsupport",
which need to be enabled to create queue pair.
Signed-off-by: NSawan Chandak <sawan.chandak@cavium.com>
Signed-off-by: NMichael Hernandez <michael.hernandez@cavium.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@cavium.com>
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Properly initialize IO statistics to avoid initial 0xFFFFFFF (-1) values.

Cleanup/simplify usage of pointer to statistics structure.
Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When VP decoupling enabled, there could be a window where, FLOGI from initiators
can be dropped before VP0 is enabled, causing link level recovery.
Retry FLOGI to avoid link level recovery.
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If we fail to queue an srb for an async login we should set the
relogin flag so it will be retried as the reason for the queuing
failure was most likely transient.  Failure to do this can lead to
failed paths as login is never retried if the relogin flag is not
set.
Signed-off-by: NChad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NSawan Chandak <sawan.chandak@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Set bit 12 of additional firmware options 3 to let firmware
hold status IOCB until ABTS response is received from Target.
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

[ Upstream Commit 84e32a06 ]

Commit 84e32a06 ("qla2xxx: Use pci_enable_msix_range() instead of
pci_enable_msix()") introduced a regression when target mode is enabled.
In qla24xx_enable_msix(), ha->max_rsp_queues was incorrectly set
to a value higher than the number of response queues allocated causing
an invalid dereference. Specifically here in qla2x00_init_rings():
    *rsp->in_ptr = 0;

Add additional check to make sure the pointer is valid. following
call stack will be seen

---- 8< ----
RIP: 0010:[<ffffffffa02ccadc>]  [<ffffffffa02ccadc>] qla2x00_init_rings+0xdc/0x320 [qla2xxx]
RSP: 0018:ffff880429447dd8  EFLAGS: 00010082
....
Call Trace:
[<ffffffffa02ceb40>] qla2x00_abort_isp+0x170/0x6b0 [qla2xxx]
[<ffffffffa02c6f77>] qla2x00_do_dpc+0x357/0x7f0 [qla2xxx]
[<ffffffffa02c6c20>] ? qla2x00_relogin+0x260/0x260 [qla2xxx]
[<ffffffff8107d2c9>] kthread+0xc9/0xe0
[<ffffffff8107d200>] ? flush_kthread_worker+0x90/0x90
[<ffffffff8172cc6f>] ret_from_fork+0x3f/0x70
[<ffffffff8107d200>] ? flush_kthread_worker+0x90/0x90
---- 8< ----

Cc: <stable@vger.kernel.org>
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Driver has following initialization sequence for Target mode

1. Driver initialization starts

2. ISP Abort is scheduled when the target is enabled.

qla2xxx [0000:04:00.0]-4807:25: ISP abort scheduled
qla2xxx [0000:04:00.0]-00af:25: Performing ISP error recovery - ha=ffff880caa9e0000.

3. DPC thread starts the ISP Abort

4. While DPC is resetting the chip and initializing the firmware, we get
   async events from the firmware about P2P mode, LOOP UP and PORT UPDATE.

5. PRLI from a initiator is delivered to us followed by a PLOGI and then a
   SCSI command which creates a session.

6. If the SCSI command is a WRITE in this case, we issue XFR RDY and it
   gets dropped as can be seen with messages RESET-XFR because ISP Abort
   is still active

qla2xxx [0000:04:00.0]-e902:25: RESET-XFR active/old-count/new-count = 1/1/1.

7. If the SCSI command is a READ, we issue RESPONSE and they get dropped
   as well because Abort is still active.

qla2xxx [0000:04:00.0]-e901:25: RESET-RSP active/old-count/new-count = 1/1/1

8. Now eventually, ISP Abort finishes clearing the DPC flags.

qla2xxx [0000:04:00.0]-8822:25: qla2x00_abort_isp succeeded.
qla2xxx [0000:04:00.0]-4808:25: ISP abort end.

9. Since we dropped SCSI commands silently (without any responses sent
   to the initiator) initiator waits for a SCSI timeout (which is 60
   seconds in our case), Sends an ABTS which fails since there
   no se_cmd found for the tag that ABTS is referencing as the
   commands were cleaned up in Step 6 and 7.

10. Initiator send an IO after the ABTS which succeed fine.

To fix the above case, the following changes have been made:
  - To prevent target from dropping commands silently, use the online flag
    instead to check for an active chip reset. Once the port is online during
    a chip reset phase, we are good to process the commands.
  - Clean up qla2x00_restart_isp to not set the online flag and process ATIO
    as it is unnecessary. During a chip reset, interrupts are enabled only
    after setting the online flag to 1, so ATIO's won't be missed and hence
    no need to process ATIO's after setting the online flag.
Signed-off-by: NDilip Kumar Uppugandla <dilip@purestorage.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

99% of the time the ATIOQ has SCSI command.  The other 1% of time
is something else.  Most of the time this interrupt does not need
to hold the hardware_lock.  We're moving the ATIO interrupt thread
to a different lock to reduce lock contention.
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

DebugFS now will show fw_resource_count node.

FW Resource count

Original TGT exchg count[0]
current TGT exchg count[0]
original Initiator Exchange count[2048]
Current Initiator Exchange count[2048]
Original IOCB count[2078]
Current IOCB count[2067]
MAX VP count[254]
MAX FCF count[0]
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch enables Exchange offload support in Qlogic ISP.
To enable exchange offload with Qlogic ISP24XX/25XX/26XX,
set module parameter ql2xexchoffld to any non-zero number.
This will alow ISP firmware to store exchange data structures
used by firmware to host memory provided by driver. ISP firmware
can supports upto 32k total active exchanges.
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch enables Extended Logins support in Qlogic ISP.
To enable extended login with Qlogic ISP24XX/25XX/26XX,
set module parameter ql2xexlogins to any non-zero number.
This will alow ISP firmware to store port database structure
information of remote login sessions to host memory provided
by driver. ISP firmware supports upto 16k total logins.
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Execute qla25xx_manipulate_risc_semaphore() only for
ssdid 0x0175 and 0x0240.
Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Acked-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Whether htonl() or __constant_htonl() is used, if the argument
is a constant the conversion happens at compile time. Hence leave
out the __constant_ prefix for this and other endianness
conversion functions. This improves source code readability.

[jejb: checkpatch fixes]
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Acked-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Detected these variables by building with W=1.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Acked-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

There are multiple reasons for disabling this:

1. It provides no functional benefit. We pretty much only get a few more
sysfs entries for each port, but all that information is already
available from /sys/kernel/debug/target/qla-session-X

2. It already only works in private-loop mode. By disabling we'll be
getting more uniform behavior with fabric mode.

3. It creates complications for the new PLOGI handling mechanism:
scsi_transport_fc port deletion timer could race with new session
from initiator and cause logout after successful login.

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: NAlexei Potashnik <alexei@purestorage.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

RSCN processing in qla2xxx driver can run in parallel with ELS/IO
processing. As such the decision to remove disappeared fc port's
session could be stale, because a new login sequence has occurred
since and created a brand new session.

Previous mechanism of dealing with this by delaying deletion request
was prone to erroneous deletions if the event that was supposed to
cancel the deletion never arrived or has been delayed in processing.

New mechanism relies on a time-like generation counter to serialize
RSCN updates relative to ELS/IO updates.

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: NAlexei Potashnik <alexei@purestorage.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

- keep qla_tgt_sess object on the session list until it's freed

- modify use of sess->deleted flag to differentiate delayed
  session deletion that can be cancelled from irreversible one:
  QLA_SESS_DELETION_PENDING vs QLA_SESS_DELETION_IN_PROGRESS

- during IN_PROGRESS deletion all newly arrived commands and TMRs will
  be rejected, existing commands and TMRs will be terminated when
  given by the core to the fabric or simply dropped if session logout
  has already happened (logout terminates all existing exchanges)

- new PLOGI will initiate deletion of the following sessions
  (unless deletion is already IN_PROGRESS):
  - with the same port_name (with logout)
  - different port_name, different loop_id but the same port_id
    (with logout)
  - different port_name, different port_id, but the same loop_id
    (without logout)

- additionally each new PLOGI will store imm notify iocb in the
  same port_name session being deleted. When deletion process
  completes this iocb will be acked. Only the most recent PLOGI
  iocb is stored. The older ones will be terminated when replaced.

- new PRLI will initiate deletion of the following sessions
  (unless deletion is already IN_PROGRESS):
  - different port_name, different port_id, but the same loop_id
   (without logout)

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: NAlexei Potashnik <alexei@purestorage.com>
Acked-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>