tree:   https://na01.safelinks.protection.outlook.com/?url=https%3a%2f%2fgit.kernel.org%2fpub%2fscm%2flinux%2fkernel%2fgit%2ftorvalds%2flinux.git&data=01%7c01%7ckys%40microsoft.com%7ce2e0622715844b79ad7108d32796ec3c%7c72f988bf86f141af91ab2d7cd011db47%7c1&sdata=ubr4GbBaNS%2ftOz%2buJBk0CL9N0UNG9x2TidLgy6Yovg4%3d master
head:   03c21cb7
commit: dac58241 storvsc: Properly support Fibre Channel devices
date:   3 weeks ago
config: x86_64-randconfig-s3-01281016 (attached as .config)
reproduce:
        git checkout dac58241
        # save the attached .config to linux build tree
        make ARCH=x86_64

All errors (new ones prefixed by >>):

   drivers/built-in.o: In function `storvsc_remove':
>> storvsc_drv.c:(.text+0x213af7): undefined reference to `fc_remove_host'
   drivers/built-in.o: In function `storvsc_drv_init':
>> storvsc_drv.c:(.init.text+0xcbcc): undefined reference to `fc_attach_transport'
>> storvsc_drv.c:(.init.text+0xcc06): undefined reference to `fc_release_transport'
   drivers/built-in.o: In function `storvsc_drv_exit':
>> storvsc_drv.c:(.exit.text+0x123c): undefined reference to `fc_release_transport'

With this commit, the storvsc driver depends on FC atttributes. Make this
dependency explicit.
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The snic version number is expected to be 4 decimals in the form like a
netmask string with each number stored in an element in array v.
However, there is an off-by-one check on the number of elements in v
allowing one to pass a 5 decimal version number causing v[4] to be
referenced, causing a buffer overrun.  Fix the off-by-one error by
comparing to i > 3 rather than 4.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NShane Seymour <shane.seymour@hpe.com>
Reviewed-by: NEwan Milne <emilne@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The return value of of_ioremap on failure should be -ENODEV and not
-1.

Found using Coccinelle. A simplified version of the semantic patch
used is:

//<smpl>
@@
expression *e;
@@

e = of_ioremap(...);
if (e == NULL) {
...
return
- -1
+ -ENODEV
;
}
//</smpl>

The single call site only checks that the return value is less than 0,
hence no change is required at the call site.
Signed-off-by: NAmitoj Kaur Chawla <amitoj1606@gmail.com>
Reviewed-by: NShane Seymour <shane.seymour@hpe.com>
Reviewed-by: NHannes Reinicke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This bug causes the wrong command to have its sense pointer overwritten,
which sometimes leads to a NULL pointer deref. Fix this by checking which
command is being requeued before restoring the scsi_eh_save data.

It turns out that some targets will disconnect a REQUEST SENSE command.
The autosense algorithm doesn't anticipate this. Hence multiple commands
can end up undergoing autosense simultaneously, and they will all try to
use the same scsi_eh_save struct, which won't work. Defer autosense when
the scsi_eh_save storage is in use by another command.

Fixes: f27db8eb ("ncr5380: Fix autosense bugs")
Reported-and-tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add missing checks for EH abort during arbitration and selection.
Rework the handling of NCR5380_select() result to improve clarity.

Fixes: 707d62b3 ("ncr5380: Fix EH during arbitration and selection")
Tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The list structures and related logic used in the NCR5380 driver mean that
a command cannot be queued twice (i.e. can't appear on more than one queue
and can't appear on the same queue more than once).

The abort handler must forget the command so that the mid-layer can re-use
it. E.g. the ML may send it back to the LLD via via scsi_eh_get_sense().

Fix this and also fix two error paths, so that commands get forgotten iff
completed.

Fixes: 8b00c3d5 ("ncr5380: Implement new eh_abort_handler")
Tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Calling NCR5380_select() from the abort handler causes various problems.
Firstly, it means potentially re-entering NCR5380_select(). Secondly, it
means that the lock is released, which permits the EH handlers to be
re-entered. The combination results in crashes. Don't do it.

Fixes: 8b00c3d5 ("ncr5380: Implement new eh_abort_handler")
Reported-and-tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The calls to NCR5380_transfer_pio() for DATA IN and DATA OUT phases will
modify cmd->SCp.this_residual, cmd->SCp.ptr and cmd->SCp.buffer. That
works as long as EH does not intervene, which became possible in
atari_NCR5380.c when I changed the locking to bring it closer to
NCR5380.c.

If error recovery aborts the command, the scsi_cmnd in question and its
buffer will be returned to the mid-layer. So the transfer has to cease,
but it can't be stopped by the initiator because the target controls the
bus phase.

The problem does not arise if the lock is not released. That was fine for
atari_scsi, because it implements DMA. For the other drivers, we have to
release the lock and re-enable interrupts for long PIO data transfers.

The solution is to split the transfer into small chunks. In between chunks
the main loop releases the lock and re-enables interrupts. Thus interrupts
can be serviced and eh_bus_reset_handler can intervene if need be.

This fixes an oops in NCR5380_transfer_pio() that can happen when the EH
abort handler is invoked during DATA IN or DATA OUT phase.

Fixes: 11d2f63b ("ncr5380: Change instance->host_lock to hostdata->lock")
Reported-and-tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Commands subject to exception handling are to be returned to the scsi
mid-layer. Make sure that the various command pointers and command lists
in the low-level driver are correctly cleansed of affected commands.

This fixes some bugs that I accidentally introduced in v4.5-rc1 including
the removal of INIT_LIST_HEAD for the 'autosense' and 'disconnected'
command lists, and the possible NULL pointer dereference in
NCR5380_bus_reset() that was reported by Dan Carpenter.

hostdata->sensing may also point to an affected command so this pointer
also has to be cleared. The abort handler calls complete_cmd() to take
care of this; let's have the bus reset handler do the same.

The issue queue may also contain an affected command. If so, remove it.
This also follows the abort handler logic.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Fixes: 62717f53 ("ncr5380: Implement new eh_bus_reset_handler")
Tested-by: NMichael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This adds the missing error check and path for if the call to the
function hwi_init_controller fails as this error path was clearly missed
when writing beiscsi_eeh_resume and thus we must add it now in order to
be able to handle this nonrecoverable failing function call gracefully
in beiscsi_eeh_resume.
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Reviewed-by: NJitendra Bhivare <jitendra.bhivare@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Do not reset fip selection time for every advertisement
in fcoe_ctlr_recv_adv() but set it only once for the first
validated FCF. Otherwise FCF selection won't happen when the
advertisements consistently arrive with sub FCOE_CTLR_START_DELAY
periodicity.
Tested-by: NNarendra K <narendra_k@dell.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Acked-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NUsha Ketineni <usha.k.ketineni@intel.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In high-datarate aging tests, it is found that the
SCSI framework can periodically issue lu resets as
some commands timeout.
Response TASK SET FULL and SAS_QUEUE_FULL may be
returned many times for the same command, causing the
timeouts.
The SAS_QUEUE_FULL errors come from
TRANS_TX_CREDIT_TIMEOUT_ERR, TRANS_TX_CLOSE_NORMAL_ERR,
and TRANS_TX_ERR_FRAME_TXED errors. They do not mean
that the queue is full in the host, but rather it is
equivalent to meaning the queue is full for the sdev.
To overcome this, the queue depth for the sdev is
reduced to 64 (from 256, set in sas_slave_configure()).
Normally error code SAS_QUEUE_FULL will result in the
sdev queue depth falling, but it falls too slowly during
high-datarate tests and commands timeout before it
has fallen to an adequete level from original value.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When TRANS_TX_ERR_FRAME_TXED error occurs in
a slot, the command should be re-attempted.
This error is equivalent to meaning that the queue
is full in the sdev (and not the host).
A superflous debug statement is also removed in the
slot complete handler.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When TRANS_TX_CREDIT_TIMEOUT_ERR or
TRANS_TX_CLOSE_NORMAL_ERR error occur in
a slot, the command should be re-attempted.
This error is equivalent to meaning that the queue
is full in the sdev (and not the host).
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a function to abort a slot (task) in the target
device and then cleanup and complete the task.
The function is called from work queue context as
it cannot be called from the context where it is
triggered (interrupt).
Flag hisi_sas_slot.abort is added as the flag used
in the slot error handler to indicate whether the
slot needs to be aborted in the sdev prior to
cleanup and finish.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In hisi_sas_exec_internal_tmf_task(), the check for
SAM_STAT_GOOD is replaced with
TMF_RESP_FUNC_COMPLETE, which is a genuine tmf
response code.
SAM_STAT_GOOD and TMF_RESP_FUNC_COMPLETE have the
same value, so this is why it worked before.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

struct timeval will overflow on 32-bit systems in y2038 and is being
removed from the kernel. Replace the use of struct timeval and
do_gettimeofday() with ktime_get_real_seconds() which provides a 64-bit
seconds value and is y2038 safe.

gdth driver requires changes in two areas:

1) gdth_store_event() loads two u32 timestamp fields for ioctl GDTIOCTL_EVENT

   These timestamp fields are part of struct gdth_evt_str used for passing
   event data to userspace. At the first instance of an event we do
   (first_stamp=last_stamp="current time"). If that same event repeats,
   we do (last_stamp="current time") AND increment same_count to indicate
   how many times the event has repeated since first_stamp.

   This patch replaces the use of timeval and do_gettimeofday() with
   ktime_get_real_seconds() cast to u32 to extend the timestamp fields
   to y2106.

   Beyond y2106, the userspace tools (ie. RAID controller monitors) can
   work around the time rollover and this driver would still not need to
   change.

   Alternative: The alternative approach is to introduce a new ioctl in gdth
   with the u32 time fields defined as u64.  This would require userspace
   changes now, but not in y2106.

2)  gdth_show_info() calculates elapsed time using u32 first_stamp

    It is adding events with timestamps to a seq_file.  Timestamps are
    calculated as the "current time" minus the first_stamp.

    This patch replaces the use of timeval and do_gettimeofday() with
    ktime_get_real_seconds() cast to u32 to calculate the timestamp.

    This elapsed time calculation is safe even when the time wraps (beyond
    y2106) due to how unsigned subtraction works. A comment has been added
    to the code to indicate this safety.

    Alternative: This piece itself doesn't warrant an alternative, but
    if we do introduce a new structure & ioctl with u64 timestamps, this
    would change accordingly.
Signed-off-by: NAlison Schofield <amsfield22@gmail.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The variable is_ver1 is always true and so OSD_CAP_LEN can never be
used.

Reported by Coverity.
Signed-off-by: NSudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: NBoaz harrosh <ooo@elecrozaur.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

parport_claim() can fail and we should be checking if we were able to
claim the port.
Signed-off-by: NSudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add S3/S4 support, add .suspend and .resume function in pci_driver.  In
.suspend handler, driver send S3/S4 signal to the device.
Signed-off-by: NCharles Chiou <charles.chiou@tw.promise.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

1. Add hotplug support. Pegasus support surprise removal. To this end, I
   use return_abnormal_state function to return DID_NO_CONNECT for all
   commands which sent to driver.

2. Remove stex_hba_stop in stex_remove because we cannot send command to
   device after hotplug.

3. Add new device status: MU_STATE_STOP, MU_STATE_NOCONNECT,
   MU_STATE_STOP. MU_STATE_STOP is currently not referenced.
   MU_STATE_NOCONNECT represent that device is plugged out from the
   host.

4. Use return_abnormal_function() to substitute part of code in
   stex_do_reset.
Signed-off-by: NCharles Chiou <charles.chiou@tw.promise.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Pegasus is a high performace hardware RAID solution designed to unleash
the raw power of Thunderbolt technology.

1. Add code to distinct SuperTrack and Pegasus series by sub device ID.
   It should support backward compatibility.

2. Change the driver version.
Signed-off-by: NCharles Chiou <charles.chiou@tw.promise.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch depends on patch
 - commit ac10a3e4ed64
   ("Export function scsi_scan.c:sanitize_inquiry_string")
Suggested-by: NHannes Reinecke <hare@suse.de>
Suggested-by: Matthew R. Ochs mrochs@linux.vnet.ibm.com
Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

An oops can occur when submitting ioaccel2 commands when the phys_disk
pointer is NULL in hpsa_scsi_ioaccel_raid_map.  Happens when there are
configuration changes during I/O operations.

If the phys_disk pointer is NULL, send the command down the RAID path.
Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Aborts were not being sent down to HBA devices
Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The bitmap was changed after this definition was added to the
driver. Correcting the bitmap definition.
Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Stop annoying "Error, could not get enclosure information"
messages.
Reviewed-by: NMahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Reviewed-by: NJustin Lindley <justin.lindley@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

[mkp: Fixed merge due to patches 20-22 of series being postponed]
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If a device needs to be rescanned the device_handler might need
to be rechecked, too.
So add a 'rescan' callback to the device handler and call it
upon scsi_rescan_device(). The rescan callback will be invoked
from the Unit Attention handling of ASC/ASCQ 3F 03
(INQUIRY DATA HAS CHANGED).
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Sending a 'REPORT TARGET PORT GROUP' command is a costly operation,
as the array has to gather information about all ports.
So instead of using RTPG to poll for a status update when a port
is in transitioning we should be sending a TEST UNIT READY, and
wait for the sense code to report success.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NEwan Milne <emilne@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When we read in the target port group state we should be
updating all affected port groups, otherwise we risk
running out of sync.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When we receive a unit attention code of 'ALUA state changed'
we should recheck the state, as it might be due to an implicit
ALUA state transition. This allows us to return NEEDS_RETRY
instead of ADD_TO_MLQUEUE, allowing to terminate the retries
after a certain time.
At the same time a workqueue item might already be queued, which
should be started immediately to avoid any delays.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a new blacklist flag BLIST_SYNC_ALUA to instruct the
alua device handler to use synchronous command submission
for ALUA commands.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some arrays may only capable of handling one STPG at a time,
so this patch adds a singlethreaded workqueue for STPGs to be
submitted synchronously.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The current ALUA device_handler has two drawbacks:
- We're sending a 'SET TARGET PORT GROUP' command to every LUN,
  disregarding the fact that several LUNs might be in a port group
  and will be automatically switched whenever _any_ LUN within
  that port group receives the command.
- Whenever a LUN is in 'transitioning' mode we cannot block I/O
  to that LUN, instead the controller has to abort the command.
  This leads to increased traffic across the wire and heavy load
  on the controller during switchover.

With this patch the RTPG handling is moved to a per-portgroup
workqueue. This reduces the number of 'REPORT TARGET PORT GROUP'
and 'SET TARGET PORT GROUPS' sent to the controller as we're sending
them now per port group, and not per device as previously.
It also allows us to block I/O to any LUN / port group found to be
in 'transitioning' ALUA mode, as the workqueue item will be requeued
until the controller moves out of transitioning.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The 'relative port' field is not used, and might get stale when
the port group changes. So remove the field altogether.
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>