Commit Graph

194 Commits

Author SHA1 Message Date
Ye Bin
94d3d4777d scsi: scsi_dh_rdac: Avoid crash during rdac_bus_attach()
[ Upstream commit bc546c0c9a ]

The following BUG_ON() was observed during RDAC scan:

[595952.944297] kernel BUG at drivers/scsi/device_handler/scsi_dh_rdac.c:427!
[595952.951143] Internal error: Oops - BUG: 0 [#1] SMP
......
[595953.251065] Call trace:
[595953.259054]  check_ownership+0xb0/0x118
[595953.269794]  rdac_bus_attach+0x1f0/0x4b0
[595953.273787]  scsi_dh_handler_attach+0x3c/0xe8
[595953.278211]  scsi_dh_add_device+0xc4/0xe8
[595953.282291]  scsi_sysfs_add_sdev+0x8c/0x2a8
[595953.286544]  scsi_probe_and_add_lun+0x9fc/0xd00
[595953.291142]  __scsi_scan_target+0x598/0x630
[595953.295395]  scsi_scan_target+0x120/0x130
[595953.299481]  fc_user_scan+0x1a0/0x1c0 [scsi_transport_fc]
[595953.304944]  store_scan+0xb0/0x108
[595953.308420]  dev_attr_store+0x44/0x60
[595953.312160]  sysfs_kf_write+0x58/0x80
[595953.315893]  kernfs_fop_write+0xe8/0x1f0
[595953.319888]  __vfs_write+0x60/0x190
[595953.323448]  vfs_write+0xac/0x1c0
[595953.326836]  ksys_write+0x74/0xf0
[595953.330221]  __arm64_sys_write+0x24/0x30

Code is in check_ownership:

	list_for_each_entry_rcu(tmp, &h->ctlr->dh_list, node) {
		/* h->sdev should always be valid */
		BUG_ON(!tmp->sdev);
		tmp->sdev->access_state = access_state;
	}

	rdac_bus_attach
		initialize_controller
			list_add_rcu(&h->node, &h->ctlr->dh_list);
			h->sdev = sdev;

	rdac_bus_detach
		list_del_rcu(&h->node);
		h->sdev = NULL;

Fix the race between rdac_bus_attach() and rdac_bus_detach() where h->sdev
is NULL when processing the RDAC attach.

Link: https://lore.kernel.org/r/20210113063103.2698953-1-yebin10@huawei.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 11:42:20 +09:00
Ewan D. Milne
b2937734c4 scsi: scsi_dh_alua: Remove check for ASC 24h in alua_rtpg()
[ Upstream commit bc3f2b42b7 ]

Some arrays return ILLEGAL_REQUEST with ASC 00h if they don't support the
RTPG extended header so remove the check for INVALID FIELD IN CDB.

Link: https://lore.kernel.org/r/20210331201154.20348-1-emilne@redhat.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 10:54:11 +09:00
Hannes Reinecke
dd09535b6e scsi: scsi_dh_alua: Avoid crash during alua_bus_detach()
[ Upstream commit 5faf50e9e9 ]

alua_bus_detach() might be running concurrently with alua_rtpg_work(), so
we might trip over h->sdev == NULL and call BUG_ON().  The correct way of
handling it is to not set h->sdev to NULL in alua_bus_detach(), and call
rcu_synchronize() before the final delete to ensure that all concurrent
threads have left the critical section.  Then we can get rid of the
BUG_ON() and replace it with a simple if condition.

Link: https://lore.kernel.org/r/1600167537-12509-1-git-send-email-jitendra.khasdev@oracle.com
Link: https://lore.kernel.org/r/20200924104559.26753-1-hare@suse.de
Cc: Brian Bunker <brian@purestorage.com>
Acked-by: Brian Bunker <brian@purestorage.com>
Tested-by: Jitendra Khasdev <jitendra.khasdev@oracle.com>
Reviewed-by: Jitendra Khasdev <jitendra.khasdev@oracle.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 09:47:23 +09:00
Hannes Reinecke
da7bfd219b scsi: scsi_dh_alua: handle RTPG sense code correctly during state transitions
[ Upstream commit b6ce6fb121 ]

Some arrays are not capable of returning RTPG data during state
transitioning, but rather return an 'LUN not accessible, asymmetric access
state transition' sense code. In these cases we can set the state to
'transitioning' directly and don't need to evaluate the RTPG data (which we
won't have anyway).

Link: https://lore.kernel.org/r/20191007135701.32389-1-hare@suse.de
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-15 14:56:51 +09:00
Hannes Reinecke
331c7c114c scsi: scsi_dh_alua: always use a 2 second delay before retrying RTPG
[ Upstream commit 20122994e3 ]

Retrying immediately after we've received a 'transitioning' sense code is
pretty much pointless, we should always use a delay before retrying.  So
ensure the default delay is applied before retrying.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Tested-by: Zhangguanghui <zhang.guanghui@h3c.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-15 14:17:23 +09:00
Dan Carpenter
10ae484533 scsi: scsi_dh_emc: return success in clariion_std_inquiry()
[ Upstream commit 4d7d39a18b ]

We accidentally return an uninitialized variable on success.

Fixes: b6ff1b14cd ("[SCSI] scsi_dh: Update EMC handler")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-21 17:21:36 +02:00
Bart Van Assche
8f9155989f scsi: scsi_dh_alua: Ensure that alua_activate() calls the completion function
commit 7cb689fe42 upstream.

Callers of scsi_dh_activate(), e.g. dm-mpath, assume that this function
either returns an error code or calls the completion function. Make
alua_activate() call the completion function even if scsi_device_get()
fails.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 09:30:33 +02:00
Bart Van Assche
68b275b7cb scsi: scsi_dh_alua: Check scsi_device_get() return value
commit 625fe857e4 upstream.

Do not queue ALUA work nor call scsi_device_put() if the
scsi_device_get() call fails. This patch fixes the following crash:

general protection fault: 0000 [#1] SMP
RIP: 0010:scsi_device_put+0xb/0x30
Call Trace:
 scsi_disk_put+0x2d/0x40
 sd_release+0x3d/0xb0
 __blkdev_put+0x29e/0x360
 blkdev_put+0x49/0x170
 dm_put_table_device+0x58/0xc0 [dm_mod]
 dm_put_device+0x70/0xc0 [dm_mod]
 free_priority_group+0x92/0xc0 [dm_multipath]
 free_multipath+0x70/0xc0 [dm_multipath]
 multipath_dtr+0x19/0x20 [dm_multipath]
 dm_table_destroy+0x67/0x120 [dm_mod]
 dev_suspend+0xde/0x240 [dm_mod]
 ctl_ioctl+0x1f5/0x520 [dm_mod]
 dm_ctl_ioctl+0xe/0x20 [dm_mod]
 do_vfs_ioctl+0x8f/0x700
 SyS_ioctl+0x3c/0x70
 entry_SYSCALL_64_fastpath+0x18/0xad

Fixes: commit 03197b61c5 ("scsi_dh_alua: Use workqueue for RTPG")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 09:30:32 +02:00
Bart Van Assche
df3d422cba scsi: scsi_dh_alua: Fix a reference counting bug
The code at the end of alua_rtpg_work() is as follows:

	scsi_device_put(sdev);
	kref_put(&pg->kref, release_port_group);

In other words, alua_rtpg_queue() must hold an sdev reference and a pg
reference before queueing rtpg work. If no rtpg work is queued no
additional references should be held when alua_rtpg_queue() returns. If
no rtpg work is queued, ensure that alua_rtpg_queue() only gives up the
sdev reference if that reference was obtained by the same
alua_rtpg_queue() call.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reported-by: Tang Junhui <tang.junhui@zte.com.cn>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Tang Junhui <tang.junhui@zte.com.cn>
Cc: <stable@vger.kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-01 13:32:24 -04:00
tang.junhui
1fdd14279e scsi: scsi_dh_alua: fix missing kref_put() in alua_rtpg_work()
Reference count of pg leaks in alua_rtpg_work() since kref_put() is not
called to decrease the reference count of pg when the condition
pg->rtpg_sdev==NULL satisfied (actually it is easy to satisfy), it would
cause memory of pg leakage.

Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Cc: <stable@vger.kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-01 13:31:08 -04:00
tang.junhui
086acff2cf scsi: scsi_dh_alua: Fix memory leak in alua_rtpg()
buff should be freed before returning with SCSI_DH_RETRY in alua_rtpg().

Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-26 20:42:38 -04:00
James Bottomley
e7ca7f9fa2 Merge branch 'fixes' into misc 2016-05-17 21:12:50 -04:00
Hannes Reinecke
fe8b9534a0 scsi_dh_alua: do not fail for unknown VPD identification
Not every device will return a useable VPD identification, but still
might support ALUA. Rather than disable ALUA support we should be
allowing the device identification to be empty and attach individual
ALUA device handler to each devices.

[mkp: Fixed typo reported by Bart]

Reported-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Tested-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-05-10 21:31:17 -04:00
Dan Carpenter
a4bd852031 scsi_dh_alua: uninitialized variable in alua_rtpg()
It's possible to use "err" without initializing it.  If it happens to be
a 2 which is SCSI_DH_RETRY then that could cause a bug.  Bart Van Assche
pointed out that we should probably re-initialize it for every iteration
through the retry loop.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com>
2016-04-30 09:24:50 -07:00
Bart Van Assche
1f275f976f scsi_dh_alua: Declare local functions static
This patch avoids that building with W=1 causes gcc to report the
following type of warning:

    no previous prototype for ... [-Wmissing-prototypes]

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-15 16:53:19 -04:00
Bart Van Assche
38c3159923 scsi_dh_alua: Fix a recently introduced deadlock
While retesting the SRP initiator I ran the command "rmmod mlx4_ib"
while I/O was in progress. That command triggers SCSI device removal
indirectly. Avoid that this action triggers the following deadlock:

=================================
[ INFO: inconsistent lock state ]
4.6.0-rc0-dbg+ #2 Tainted: G           O
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
multipathd/484 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&pg->lock)->rlock){+.?...}, at: [<ffffffffa04f50a2>] alua_bus_detach+0x52/0xa0 [scsi_dh_alua]
{IN-SOFTIRQ-W} state was registered at:
  [<ffffffff810a64a9>] __lock_acquire+0x7e9/0x1ad0
  [<ffffffff810a7fd0>] lock_acquire+0x60/0x80
  [<ffffffff8159910e>] _raw_spin_lock_irqsave+0x3e/0x60
  [<ffffffffa04f5131>] alua_rtpg_queue+0x41/0x1d0 [scsi_dh_alua]
  [<ffffffffa04f5531>] alua_check+0xe1/0x220 [scsi_dh_alua]
  [<ffffffffa04f5709>] alua_check_sense+0x99/0xb0 [scsi_dh_alua]
  [<ffffffff813f0d01>] scsi_check_sense+0x71/0x3f0
  [<ffffffff813f2f8b>] scsi_decide_disposition+0x18b/0x1d0
  [<ffffffff813f6e52>] scsi_softirq_done+0x52/0x140
  [<ffffffff812a26f2>] blk_done_softirq+0x52/0x90
  [<ffffffff8105bc1f>] __do_softirq+0x10f/0x230
  [<ffffffff8105bec8>] irq_exit+0xa8/0xb0
  [<ffffffff8101a675>] do_IRQ+0x65/0x110
  [<ffffffff8159a2c9>] ret_from_intr+0x0/0x19
  [<ffffffff811732f1>] kmem_cache_alloc+0x151/0x190
  [<ffffffff8118e534>] create_object+0x34/0x2d0
  [<ffffffff8158eaa6>] kmemleak_alloc_percpu+0x56/0xd0
  [<ffffffff8113ab0d>] pcpu_alloc+0x38d/0x660
  [<ffffffff8113aded>] __alloc_percpu_gfp+0xd/0x10
  [<ffffffff812e56a5>] __percpu_counter_init+0x55/0xb0
  [<ffffffff812b4989>] blkg_alloc+0x79/0x230
  [<ffffffff812b6756>] blkcg_init_queue+0x26/0x1d0
  [<ffffffff81297eed>] blk_alloc_queue_node+0x27d/0x2e0
  [<ffffffffa017766c>] dm_create+0x20c/0x570 [dm_mod]
  [<ffffffffa017e356>] dev_create+0x56/0x2c0 [dm_mod]
  [<ffffffffa017dcae>] ctl_ioctl+0x26e/0x520 [dm_mod]
  [<ffffffffa017df6e>] dm_ctl_ioctl+0xe/0x20 [dm_mod]
  [<ffffffff811aa8ee>] do_vfs_ioctl+0x8e/0x660
  [<ffffffff811aaefc>] SyS_ioctl+0x3c/0x70
  [<ffffffff81599929>] entry_SYSCALL_64_fastpath+0x1c/0xac
irq event stamp: 4290931
hardirqs last  enabled at (4290931): [ 1662.892772]
[<ffffffff81599341>] _raw_spin_unlock_irqrestore+0x31/0x50
hardirqs last disabled at (4290930): [<ffffffff815990e7>] _raw_spin_lock_irqsave+0x17/0x60
softirqs last  enabled at (4290774): [<ffffffff8105bcdb>] __do_softirq+0x1cb/0x230
softirqs last disabled at (4289831): [<ffffffff8105bec8>] irq_exit+0xa8/0xb0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&pg->lock)->rlock);
  <Interrupt>
    lock(&(&pg->lock)->rlock);

 *** DEADLOCK ***

2 locks held by multipathd/484:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff811d1cc3>] __blkdev_put+0x33/0x360
 #1:  (sd_ref_mutex){+.+...}, at: [<ffffffff81400afc>] scsi_disk_put+0x1c/0x40

stack backtrace:
CPU: 6 PID: 484 Comm: multipathd Tainted: G           O    4.6.0-rc0-dbg+ #2
Call Trace:
 [<ffffffff812bd115>] dump_stack+0x67/0x92
 [<ffffffff810a5175>] print_usage_bug+0x215/0x240
 [<ffffffff810a56ea>] mark_lock+0x54a/0x610
 [<ffffffff810a6505>] __lock_acquire+0x845/0x1ad0
 [<ffffffff810a7fd0>] lock_acquire+0x60/0x80
 [<ffffffff81598f23>] _raw_spin_lock+0x33/0x50
 [<ffffffffa04f50a2>] alua_bus_detach+0x52/0xa0 [scsi_dh_alua]
 [<ffffffff813ff6f7>] scsi_dh_release_device+0x17/0x50
 [<ffffffff813fb8da>] scsi_device_dev_release_usercontext+0x2a/0x120
 [<ffffffff810701f0>] execute_in_process_context+0x80/0x90
 [<ffffffff813fb8a7>] scsi_device_dev_release+0x17/0x20
 [<ffffffff813c8cfd>] device_release+0x2d/0x90
 [<ffffffff812bfa8a>] kobject_release+0x7a/0x190
 [<ffffffff812bf946>] kobject_put+0x26/0x50
 [<ffffffff813c8ee2>] put_device+0x12/0x20
 [<ffffffff813edc86>] scsi_device_put+0x26/0x30
 [<ffffffff81400b0d>] scsi_disk_put+0x2d/0x40
 [<ffffffff81400b68>] sd_release+0x48/0xb0
 [<ffffffff811d1f2e>] __blkdev_put+0x29e/0x360
 [<ffffffff811d24b9>] blkdev_put+0x49/0x170
 [<ffffffff811d2600>] blkdev_close+0x20/0x30
 [<ffffffff81198f48>] __fput+0xe8/0x1f0
 [<ffffffff81199089>] ____fput+0x9/0x10
 [<ffffffff81075d9e>] task_work_run+0x6e/0xa0
 [<ffffffff81001119>] exit_to_usermode_loop+0xa9/0xb0
 [<ffffffff81001590>] syscall_return_slowpath+0xb0/0xc0
 [<ffffffff815999b7>] entry_SYSCALL_64_fastpath+0xaa/0xac

Fixes: cb0a168cb6 (scsi_dh_alua: update 'access_state' field)
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-29 20:32:02 -04:00
Dan Carpenter
100bcb851b scsi_dh_alua: uninitialized variable in alua_check_vpd()
The pg_updated variable is support to be set to false at the start but
it is uninitialized.

Fixes: cb0a168cb6 ('scsi_dh_alua: update 'access_state' field')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-14 21:04:59 -04:00
Hannes Reinecke
0323375c8b scsi_dh_emc: update 'access_state' field
Update the 'access_state' field of the SCSI device whenever the path
state changes.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:20:33 -05:00
Hannes Reinecke
1a5dc166cd scsi_dh_rdac: update 'access_state' field
Track attached SCSI devices and update the 'access_state' whenever the
path state of the device changes.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:18:28 -05:00
Hannes Reinecke
cb0a168cb6 scsi_dh_alua: update 'access_state' field
Track attached SCSI devices and update the 'access_state' field whenever
an ALUA state change has been detected.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:17:34 -05:00
Hannes Reinecke
5115fc7e2e scsi_dh_alua: use common definitions for ALUA state
scsi_proto.h now contains definitions for the ALUA state, so we don't
have to carry them in the device handler.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-05 17:16:48 -05:00
Hannes Reinecke
e79c82cca6 scsi_dh_alua: Update version to 2.0
[mkp: Fixed merge due to patches 20-22 of series being postponed]

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
d3d328919f scsi_dh: add 'rescan' callback
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
9d2c303952 scsi_dh_alua: Send TEST UNIT READY to poll for transitioning
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
c57168a1e1 scsi_dh_alua: update all port states
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
2b35865e7a scsi_dh_alua: Recheck state on unit attention
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
851cde9909 scsi_dh_alua: Add new blacklist flag 'BLIST_SYNC_ALUA'
Add a new blacklist flag BLIST_SYNC_ALUA to instruct the
alua device handler to use synchronous command submission
for ALUA commands.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
00642a1bff scsi_dh_alua: Allow workqueue to run synchronously
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
03197b61c5 scsi_dh_alua: Use workqueue for RTPG
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: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
7af33612f4 scsi_dh_alua: remove 'rel_port' from alua_dh_data structure
The 'relative port' field is not used, and might get stale when
the port group changes. So remove the field altogether.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
aa90f49036 scsi_dh_alua: move optimize_stpg evaluation
When the optimize_stpg module option is set we should just set it
once during port_group allocation. Doing so allows us to override
it later with device specific settings.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
28261402dd revert commit a8e5a2d593 ("[SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is transitioning")
This reverts commit a8e5a2d593

Obsoleted by the next patch.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
a4253fde53 scsi_dh_alua: simplify alua_initialize()
Rework alua_check_vpd() to use scsi_vpd_get_tpg()
and move the port group selection into the function, too.
With that we can simplify alua_initialize() to just
call alua_check_tpgs() and alua_check_vpd();

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
0047220c6c scsi_dh_alua: use unique device id
Use scsi_vpd_lun_id() to assign a unique device identification
to the alua port group structure.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
43394c67f8 scsi_dh_alua: Use separate alua_port_group structure
The port group needs to be a separate structure as several
LUNs might belong to the same group.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
c49c83458f scsi_dh_alua: allocate RTPG buffer separately
The RTPG buffer will only evaluated within alua_rtpg(),
so we can allocate it locally there and avoid having to
put it into the global structure.

Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
40bb61a773 scsi_dh_alua: switch to scsi_execute_req_flags()
All commands are issued synchronously, so no need to open-code
scsi_execute_req_flags() anymore. And we can get rid of the
static sense code structure element. scsi_execute_req_flags()
will be setting REQ_QUIET and REQ_PREEMPT, but that is
perfectly fine as we're evaluating and logging any errors
ourselves and we really need to send the command even if
the device is quiesced.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
dd5cc4086b scsi_dh_alua: call alua_rtpg() if stpg fails
If the call to SET TARGET PORT GROUPS fails we have no idea what
state the array is left in, so we need to issue a call to
REPORT TARGET PORT GROUPS in these cases.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
b246075666 scsi_dh_alua: Make stpg synchronous
The 'activate_complete' function needs to be executed after
stpg has finished, so we can as well execute stpg synchronously
and call the function directly.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
f2ecf13a24 scsi_dh_alua: separate out alua_stpg()
Separate out SET TARGET PORT GROUP functionality into a separate
function alua_stpg().

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
d42ae5f338 scsi_dh_alua: Pass buffer as function argument
Pass in the buffer as a function argument for submit_rtpg().

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Arnd Bergmann
0c994c03c9 scsi_dh: force modular build if SCSI is a module
When the scsi_dh core was moved into the scsi core module,
CONFIG_SCSI_DH became a 'bool' option, and now anything depending on it
can be built-in even when CONFIG_SCSI=m. This of course cannot link
successfully:

drivers/scsi/built-in.o: In function `rdac_init':
scsi_dh_alua.c:(.init.text+0x14): undefined reference to `scsi_register_device_handler'
scsi_dh_alua.c:(.init.text+0x64): undefined reference to `scsi_unregister_device_handler'
drivers/scsi/built-in.o: In function `alua_init':
scsi_dh_alua.c:(.init.text+0xb0): undefined reference to `scsi_register_device_handler'

As a workaround, this adds an extra dependency on CONFIG_SCSI, so
Kconfig can figure out whether built-in is allowed or not.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 086b91d052 ("scsi_dh: integrate into the core SCSI code")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-23 21:27:02 -05:00
Hannes Reinecke
d2d06d4fe0 scsi_dh_rdac: always retry MODE SELECT on command lock violation
If MODE SELECT returns with sense '05/91/36' (command lock violation)
it should always be retried without counting the number of retries.
During an HBA upgrade or similar circumstances one might see a flood
of MODE SELECT command from various HBAs, which will easily trigger
the sense code and exceed the retry count.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-04 22:26:06 -05:00
Hannes Reinecke
23211c1e7a scsi_dh_alua: Remove stale variables
With commit 83ea0e5e35 ("scsi_dh_alua: use scsi_vpd_tpg_id()") these
variables became obsolete, but weren't removed.

[mkp: Fixed checkpatch warning]

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-07 20:11:25 -05:00
Hannes Reinecke
83ea0e5e35 scsi_dh_alua: use scsi_vpd_tpg_id()
Use the common function 'scsi_vpd_tpg_id()' instead of open-coding
it in scsi_dh_alua.

[mkp: Applied by hand]

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:59:01 -05:00
Hannes Reinecke
e2d817db32 scsi_dh_alua: simplify sense code handling
Most sense code is already handled in the generic
code, so we shouldn't be adding special cases here.
However, when doing so we need to check for
unit attention whenever we're sending an internal
command.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:38:20 -05:00
Hannes Reinecke
ad0ea64c53 scsi_dh_alua: rework alua_check_tpgs() to return the tpgs mode
Instead of returning an error code in alua_check_tpgs() we should
rather return the tpgs mode directly and have a cleaner syntax.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:37:55 -05:00
Hannes Reinecke
a7089770b9 scsi_dh_alua: use unaligned access macros
Use 'get_unaligned_XX' and 'put_unaligned_XX' instead of
open-coding it.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:37:14 -05:00
Hannes Reinecke
6c4fc04491 scsi_dh_alua: use flag for RTPG extended header
We should be using a flag when RTPG extended header is not
supported, that saves us sending RTPG twice for older arrays.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:36:44 -05:00
Hannes Reinecke
dac173ee7e scsi_dh_alua: fixup description of stpg_endio()
Fixup copy-and-paste error in the description of stpg_endio().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-02 16:35:31 -05:00