Commit Graph

102 Commits

Author SHA1 Message Date
Christoph Hellwig
909657615d scsi: libsas: allow async aborts
We now first try to call ->eh_abort_handler from a work queue, but libsas
was always failing that for no good reason.  Allow async aborts.

Reviewed-by: Johannes Thumshirn <jth@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-06 13:07:32 -04:00
Christoph Hellwig
28917d40e6 scsi: libsas: remove sas_scsi_timed_out
EH_NOT_HANDLED is the default case if no eh_timed_out method is
provided, so there is no need to supply it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-02-06 19:09:12 -05:00
Christoph Hellwig
efc3c1df5f scsi: remove ->change_queue_type method
Since we got rid of ordered tag support in 2010 the prime use case of
switching on and off ordered tags has been obsolete.  The other function
of enabling/disabling tagging entirely has only been correctly implemented
by the 53c700 driver and isn't generally useful.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-12-04 09:55:45 +01:00
Christoph Hellwig
79855d1785 libsas: remove task_collector mode
The task_collector mode (or "latency_injector", (C) Dan Willians) is an
optional I/O path in libsas that queues up scsi commands instead of
directly sending it to the hardware.  It generall increases latencies
to in the optiomal case slightly reduce mmio traffic to the hardware.

Only the obsolete aic94xx driver and the mvsas driver allowed to use
it without recompiling the kernel, and most drivers didn't support it
at all.

Remove the giant blob of code to allow better optimizations for scsi-mq
in the future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
2014-11-27 16:40:24 +01:00
Christoph Hellwig
db5ed4dfd5 scsi: drop reason argument from ->change_queue_depth
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 14:45:27 +01:00
Christoph Hellwig
c40ecc12cf scsi: avoid ->change_queue_depth indirection for queue full tracking
All drivers use the implementation for ramping the queue up and down, so
instead of overloading the change_queue_depth method call the
implementation diretly if the driver opts into it by setting the
track_queue_depth flag in the host template.

Note that a few drivers validated the new queue depth in their
change_queue_depth method, but as we never go over the queue depth
set during slave_configure or the sysfs file this isn't nessecary
and can safely be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
2014-11-24 14:45:12 +01:00
Christoph Hellwig
ee11560f3a scsi: don't force tagged_supported in drivers
Now that we also get proper values in cmd->request->tag for untagged
commands, there is no need to force tagged_supported to on in drivers
that need host-wide tags.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:44 +01:00
Christoph Hellwig
c8b09f6fb6 scsi: don't set tagging state from scsi_adjust_queue_depth
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth.  For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.

Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway.  The one other case looks
broken, but I've kept the behavior as-is for now.

Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.

Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-11-12 11:19:43 +01:00
Christoph Hellwig
2ecb204d07 scsi: always assign block layer tags if enabled
Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq.  This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:43 +01:00
Christoph Hellwig
7466501608 scsi: convert host_busy to atomic_t
Avoid taking the host-wide host_lock to check the per-host queue limit.
Instead we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
2014-07-25 07:43:43 -04:00
Hannes Reinecke
9cb78c16f5 scsi: use 64-bit LUNs
The SCSI standard defines 64-bit values for LUNs, and large arrays
employing large or hierarchical LUN numbers become more and more
common.

So update the linux SCSI stack to use 64-bit LUN numbers.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17 22:07:37 +02:00
Dan Williams
3af74a3c07 [SCSI] libsas: introduce scmd_dbg() to quiet false positive "timeout" messages
libsas sometimes short circuits timeouts to force commands into error
recovery.  It is misleading to log that the command timed-out in
sas_scsi_timed_out() when in fact it was just queued for error handling.
It's also redundant in the case of a true timeout as libata eh will
detect and report timeouts via it's AC_ERR_TIMEOUT facility.

Given that some environments consider "timeout" errors to be indicative
of impending device failure demote the sas_scsi_timed_out() timeout
message to be disabled by default.  This parallels ata_scsi_timed_out().

[jejb: checkpatch fix]
Reported-by: Xun Ni <xun.ni@intel.com>
Tested-by: Nelson Cheng <nelson.cheng@intel.com>
Acked-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:18:53 -07:00
James Bottomley
e73823f7a2 [SCSI] libsas: implement > 16 byte CDB support
Remove the arbitrary expectation in libsas that all SCSI commands are 16 bytes
or less.  Instead do all copies via cmd->cmd_len (and use a pointer to this in
the libsas task instead of a copy).  Note that this still doesn't enable > 16
byte CDB support in the underlying drivers because their internal format has
to be fixed and the wire format of > 16 byte CDBs according to the SAS spec is
different.  the libsas drivers (isci, aic94xx, mvsas and pm8xxx are all
updated for this change.

Cc: Lukasz Dorau <lukasz.dorau@intel.com>
Cc: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jack Wang <xjtuwjp@gmail.com>
Cc: Lindar Liu <lindar_liu@usish.com>
Cc: Xiangliang Yu <yuxiangl@marvell.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-06-04 11:15:59 -07:00
Dan Williams
f0bf750c2d [SCSI] libsas: trim sas_task of slow path infrastructure
The timer and the completion are only used for slow path tasks (smp, and
lldd tmfs), yet we incur the allocation space and cpu setup time for
every fast path task.

Cc: Xiangliang Yu <yuxiangl@marvell.com>
Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:54 +01:00
Dan Williams
e7db822996 [SCSI] libsas: use ->lldd_I_T_nexus_reset for ->eh_bus_reset_handler
sas_eh_bus_reset_handler() amounts to sas_phy_reset() without
notification of the reset to the lldd.  If this is triggered from
eh-cmnd recovery there may be sas_tasks for the lldd to terminate, so
->lldd_I_T_nexus_reset is warranted.

Cc: Xiangliang Yu <yuxiangl@marvell.com>
Cc: Luben Tuikov <ltuikov@yahoo.com>
Cc: Jack Wang <jack_wang@usish.com>
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
[jacek: modify pm8001_I_T_nexus_reset to return -ENODEV]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:51 +01:00
Dan Williams
9524c68218 [SCSI] libsas: add sas_eh_abort_handler
When recovering failed eh-cmnds let the lldd attempt an abort via
scsi_abort_eh_cmnd before escalating.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:50 +01:00
Dan Williams
5db45bdc87 [SCSI] libsas: enforce eh strategy handlers only in eh context
The strategy handlers may be called in places that are problematic for
libsas (i.e. sata resets outside of domain revalidation filtering /
libata link recovery), or problematic for userspace (non-blocking ioctl
to sleeping reset functions).  However, these routines are also called
for eh escalations and recovery of scsi_eh_prep_cmnd(), so permit them
as long as we are running in the host's error handler, otherwise arrange
for them to be triggered in eh_context.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:50 +01:00
Maciej Trela
36fed49805 [SCSI] libsas: cleanup spurious calls to scsi_schedule_eh
eh is woken up automatically by the presence of failed commands,
scsi_schedule_eh is reserved for cases where there are no failed
commands.  This guarantees that host_eh_sceduled is only incremented
when an explicit eh request is made.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
[fixed spurious delete of sas_ata_task_abort]
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:47 +01:00
Dan Williams
e4a9c3732c [SCSI] libata, libsas: introduce sched_eh and end_eh port ops
When managing shost->host_eh_scheduled libata assumes that there is a
1:1 shost-to-ata_port relationship.  libsas creates a 1:N relationship
so it needs to manage host_eh_scheduled cumulatively at the host level.
The sched_eh and end_eh port port ops allow libsas to track when domain
devices enter/leave the "eh-pending" state under ha->lock (previously
named ha->state_lock, but it is no longer just a lock for ha->state
changes).

Since host_eh_scheduled indicates eh without backing commands pinning
the device it can be deallocated at any time.  Move the taking of the
domain_device reference under the port_lock to guarantee that the
ata_port stays around for the duration of eh.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:45 +01:00
Dan Williams
26a2e68f81 [SCSI] libsas: don't recover end devices attached to disabled phys
If userspace has decided to disable a phy the kernel should honor that
and not inadvertantly re-enable the phy via error recovery.  This is
more straightforward in the sata case where link recovery (via
libata-eh) is separate from sas_task cancelling in libsas-eh.  Teach
libsas to accept -ENODEV as a successful response from I_T_nexus_reset
('successful' in terms of not escalating further).

This is a more comprehensive fix then "libsas: don't recover 'gone'
devices in sas_ata_hard_reset()", as it is no longer sata-specific.

aic94xx does check the return value from sas_phy_reset() so if the phy
is disabled we proceed with clearing the I_T_nexus.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:42:51 -06:00
Dan Williams
840234745e [SCSI] libsas: fix lifetime of SAS_HA_FROZEN
Until all sas_tasks are known to no longer be in-flight this flag gates late
completions from colliding with error handling.  However, it must be cleared
prior to the submission of scsi_send_eh_cmnd() requests, otherwise those
commands will never be completed correctly.

This was spotted by slub debug:
 =============================================================================
 BUG sas_task: Objects remaining on kmem_cache_close()
 -----------------------------------------------------------------------------

 INFO: Slab 0xffffea001f0eba00 objects=34 used=1 fp=0xffff8807c3aecb00 flags=0x8000000000004080
 Pid: 22919, comm: modprobe Not tainted 3.2.0-isci+ #2
 Call Trace:
  [<ffffffff810fcdcd>] slab_err+0xb0/0xd2
  [<ffffffff810e1c50>] ? free_percpu+0x31/0x117
  [<ffffffff81100122>] ? kzalloc+0x14/0x16
  [<ffffffff81100122>] ? kzalloc+0x14/0x16
  [<ffffffff81100486>] kmem_cache_destroy+0x11d/0x270
  [<ffffffffa0112bdc>] sas_class_exit+0x10/0x12 [libsas]
  [<ffffffff81078fba>] sys_delete_module+0x1c4/0x23c
  [<ffffffff814797ba>] ? sysret_check+0x2e/0x69
  [<ffffffff8126479e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
  [<ffffffff81479782>] system_call_fastpath+0x16/0x1b
 INFO: Object 0xffff8807c3aed280 @offset=21120
 INFO: Allocated in sas_alloc_task+0x22/0x90 [libsas] age=4615311 cpu=2 pid=12966
  __slab_alloc.clone.3+0x1d1/0x234
  kmem_cache_alloc+0x52/0x10d
  sas_alloc_task+0x22/0x90 [libsas]
  sas_queuecommand+0x20e/0x230 [libsas]
  scsi_send_eh_cmnd+0xd1/0x30c
  scsi_eh_try_stu+0x4f/0x6b
  scsi_eh_ready_devs+0xba/0x6ef
  sas_scsi_recover_host+0xa35/0xab1 [libsas]
  scsi_error_handler+0x14b/0x5fa
  kthread+0x9d/0xa5
  kernel_thread_helper+0x4/0x10

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:38:09 -06:00
Dan Williams
9508a66f89 [SCSI] libsas: async ata scanning
libsas ata error handling is already async but this does not help the
scan case.  Move initial link recovery out from under host->scan_mutex,
and delay synchronization with eh until after all port probe/recovery
work has been queued.

Device ordering is maintained with scan order by still calling
sas_rphy_add() in order of domain discovery.

Since we now scan the domain list when invoking libata-eh we need to be
careful to check for fully initialized ata ports.

Acked-by: Jack Wang <jack_wang@usish.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:35:41 -06:00
Dan Williams
d230ce691c [SCSI] libsas: fix mixed topology recovery
If we have a domain with sas and sata devices there may still be sas
recovery actions to take after peeling off the commands to send to
libata.

Reported-by: Andrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:23:24 -06:00
Dan Williams
8abda4d28a [SCSI] libsas: close scsi_remove_target() vs libata-eh race
ata_port lifetime in libata follows the host.  In libsas it follows the
scsi_target.  Once scsi_remove_device() has caused all commands to be
completed it allows scsi_remove_target() to immediately proceed to
freeing the ata_port causing bug reports like:

[  848.393333] BUG: spinlock bad magic on CPU#4, kworker/u:2/5107
[  848.400262] general protection fault: 0000 [#1] SMP
[  848.406244] CPU 4
[  848.408310] Modules linked in: nls_utf8 ipv6 uinput i2c_i801 i2c_core iTCO_wdt iTCO_vendor_support ioatdma dca sg sd_mod sr_mod cdrom ahci libahci isci libsas libata scsi_transport_sas [last unloaded: scsi_wait_scan]
[  848.432060]
[  848.434137] Pid: 5107, comm: kworker/u:2 Not tainted 3.2.0-isci+ #8 Intel Corporation S2600CP/S2600CP
[  848.445310] RIP: 0010:[<ffffffff8126a68c>]  [<ffffffff8126a68c>] spin_dump+0x5e/0x8c
[  848.454787] RSP: 0018:ffff8807f868dca0  EFLAGS: 00010002
[  848.461137] RAX: 0000000000000048 RBX: ffff8807fe86a630 RCX: ffffffff817d0be0
[  848.469520] RDX: 0000000000000000 RSI: ffffffff814af1cf RDI: 0000000000000002
[  848.477959] RBP: ffff8807f868dcb0 R08: 00000000ffffffff R09: 000000006b6b6b6b
[  848.486327] R10: 000000000003fb8c R11: ffffffff81a19448 R12: 6b6b6b6b6b6b6b6b
[  848.494699] R13: ffff8808027dc520 R14: 0000000000000000 R15: 000000000000001e
[  848.503067] FS:  0000000000000000(0000) GS:ffff88083fd00000(0000) knlGS:0000000000000000
[  848.512899] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  848.519710] CR2: 00007ff77d001000 CR3: 00000007f7a5d000 CR4: 00000000000406e0
[  848.528072] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  848.536446] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  848.544831] Process kworker/u:2 (pid: 5107, threadinfo ffff8807f868c000, task ffff8807ff348000)
[  848.555327] Stack:
[  848.557959]  ffff8807fe86a630 ffff8807fe86a630 ffff8807f868dcd0 ffffffff8126a6e0
[  848.567072]  ffffffff817c142f ffff8807fe86a630 ffff8807f868dcf0 ffffffff8126a703
[  848.576190]  ffff8808027dc520 0000000000000286 ffff8807f868dd10 ffffffff814af1bb
[  848.585281] Call Trace:
[  848.588409]  [<ffffffff8126a6e0>] spin_bug+0x26/0x28
[  848.594357]  [<ffffffff8126a703>] do_raw_spin_unlock+0x21/0x88
[  848.601283]  [<ffffffff814af1bb>] _raw_spin_unlock_irqrestore+0x2c/0x65
[  848.609089]  [<ffffffffa001c103>] ata_scsi_port_error_handler+0x548/0x557 [libata]
[  848.618331]  [<ffffffff81061813>] ? async_schedule+0x17/0x17
[  848.625060]  [<ffffffffa004f30f>] async_sas_ata_eh+0x45/0x69 [libsas]
[  848.632655]  [<ffffffff810618aa>] async_run_entry_fn+0x97/0x125
[  848.639670]  [<ffffffff81057439>] process_one_work+0x207/0x38d
[  848.646577]  [<ffffffff8105738c>] ? process_one_work+0x15a/0x38d
[  848.653681]  [<ffffffff810576f7>] worker_thread+0x138/0x21c
[  848.660305]  [<ffffffff810575bf>] ? process_one_work+0x38d/0x38d
[  848.667493]  [<ffffffff8105b098>] kthread+0x9d/0xa5
[  848.673382]  [<ffffffff8106e1bd>] ? trace_hardirqs_on_caller+0x12f/0x166
[  848.681304]  [<ffffffff814b7704>] kernel_thread_helper+0x4/0x10
[  848.688324]  [<ffffffff814af534>] ? retint_restore_args+0x13/0x13
[  848.695530]  [<ffffffff8105affb>] ? __init_kthread_worker+0x5b/0x5b
[  848.702929]  [<ffffffff814b7700>] ? gs_change+0x13/0x13
[  848.709155] Code: 00 00 48 8d 88 38 04 00 00 44 8b 80 84 02 00 00 31 c0 e8 cf 1b 24 00 41 83 c8 ff 44 8b 4b 08 48 c7 c1 e0 0b 7d 81 4d 85 e4 74 10 <45> 8b 84 24 84 02 00 00 49 8d 8c 24 38 04 00 00 8b 53 04 48 89
[  848.732467] RIP  [<ffffffff8126a68c>] spin_dump+0x5e/0x8c
[  848.738905]  RSP <ffff8807f868dca0>
[  848.743743] ---[ end trace 143161646eee8caa ]---

...so arrange for the ata_port to have the same end of life as the domain
device.

Reported-by: Marcin Tomczak <marcin.tomczak@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:22:25 -06:00
Dan Williams
45c73b6519 [SCSI] libsas: pre-clean commands that won the eh vs completion race
When scrolling forward through the eh list (in a clear_q scenario) it is
possible to encounter commands that won the completion vs eh race.  Rather
than sprinkle more "if (!task)" throughout the handler just make a pass
through the list and delete the race winners before handling the rest.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:20:01 -06:00
Dan Williams
f41a0c441c [SCSI] libsas: fix sas_find_local_phy(), take phy references
In the direct-attached case this routine returns the phy on which this
device was first discovered.  Which is broken if we want to support
wide-targets, as this phy reference can become stale even though the
port is still active.

In the expander-attached case this routine tries to lookup the phy by
scanning the attached sas addresses of the parent expander, and BUG_ONs
if it can't find it.  However since eh and the libsas workqueue run
independently we can still be attempting device recovery via eh after
libsas has recorded the device as detached.  This is even easier to hit
now that eh is blocked while device domain rediscovery takes place, and
that libata is fed more timed out commands increasing the chances that
it will try to recover the ata device.

Arrange for dev->phy to always point to a last known good phy, it may be
stale after the port is torn down, but it will catch up for wide port
reconfigurations, and never be NULL.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 13:01:06 -06:00
Dan Williams
2a559f4ba4 [SCSI] libsas: sas_phy_enable via transport_sas_phy_reset
Execute the link-reset triggered by sas_phy_enable via
transport_sas_phy_reset so that it can be managed by libata.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:18:01 -06:00
Dan Williams
3a2cdf391b [SCSI] libsas: defer SAS_TASK_NEED_DEV_RESET commands to libata
lldds use the SAS_TASK_NEED_DEV_RESET interface to request that eh
perform a reset.  In the sata device case defer the commands that
triggered the reset to libata-eh context so it can perform its pre and
post reset management.

In the sas_ata_post_internal() case the reset request is falling on deaf
ears as the sas_task is immediately destroyed without any reset action.
Since it is currently a nop, and likely superfluous given the conversion
to new-style libata-eh, just drop the request.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:09:02 -06:00
Dan Williams
3944f50995 [SCSI] libsas: let libata handle command timeouts
libsas-eh if it successfully aborts an ata command will hide the timeout
condition (AC_ERR_TIMEOUT) from libata.  The command likely completes
with the all-zero task->task_status it started with.  Instead, interpret
a TMF_RESP_FUNC_COMPLETE as the end of the sas_task but keep the scmd
around for libata-eh to handle.

Tested-by: Andrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:07:15 -06:00
Dan Williams
9095a64a9a [SCSI] libsas: fix timeout vs completion race
Until we have told the lldd to forget a task a timed out operation can
return from the hardware at any time.  Since completion frees the task
we need to make sure that no tasks run their normal completion handler
once eh has decided to manage the task.  Similar to
ata_scsi_cmd_error_handler() freeze completions to let eh judge the
outcome of the race.

Task collector mode is problematic because it presents a situation where
a task can be timed out and aborted before the lldd has even seen it.
For this case we need to guarantee that a task that an lldd has been
told to forget does not get queued after the lldd says "never seen it".
With sas_scsi_timed_out we achieve this with the ->task_queue_flush
mutex, rather than adding more time.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:06:08 -06:00
Dan Williams
a3a142524a [SCSI] libsas: prevent double completion of scmds from eh
We invoke task->task_done() to free the task in the eh case, but at this
point we are prepared for scsi_eh_flush_done_q() to finish off the scmd.

Introduce sas_end_task() to capture the final response status from the
lldd and free the task.

Also take the opportunity to kill this warning.
drivers/scsi/libsas/sas_scsi_host.c: In function ‘sas_end_task’:
drivers/scsi/libsas/sas_scsi_host.c:102:3: warning: case value ‘2’ not in enumerated type ‘enum exec_status’ [-Wswitch]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:04:52 -06:00
Dan Williams
3dff5721e4 [SCSI] libsas: close error handling vs sas_ata_task_done() race
Since sas_ata does not implement ->freeze(), completions for scmds and
internal commands can still arrive concurrent with
ata_scsi_cmd_error_handler() and sas_ata_post_internal() respectively.
By the time either of those is called libata has committed to completing
the qc, and the ATA_PFLAG_FROZEN flag tells sas_ata_task_done() it has
lost the race.

In the sas_ata_post_internal() case we take on the additional
responsibility of freeing the sas_task to close the race with
sas_ata_task_done() freeing the the task while sas_ata_post_internal()
is in the process of invoking ->lldd_abort_task().

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:58:38 -06:00
Dan Williams
e139942d77 [SCSI] libsas: convert dev->gone to flags
In preparation for adding tracking of another device state "destroy".

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:51:23 -06:00
Dan Williams
312d3e5611 [SCSI] libsas: remove ata_port.lock management duties from lldds
Each libsas driver (mvsas, pm8001, and isci) has invented a different
method for managing the ap->lock.  The lock is held by the ata
->queuecommand() path.  mvsas drops it prior to acquiring any internal
locks which allows it to hold its internal lock across calls to
task->task_done().  This capability is important as it is the only way
the driver can flush task->task_done() instances to guarantee that it no
longer has any in-flight references to a domain_device at
->lldd_dev_gone() time.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:50:12 -06:00
Dan Williams
735f7d2fed [SCSI] libsas: fix domain_device leak
Arrange for the deallocation of a struct domain_device object when it no
longer has:
1/ any children
2/ references by any scsi_targets
3/ references by a lldd

The comment about domain_device lifetime in
Documentation/scsi/libsas.txt is stale as it appears mainline never had
a version of a struct domain_device that was registered as a kobject.
We now manage domain_device reference counts on behalf of external
agents.

Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:37:47 -06:00
Dan Williams
6f4e75a49f [SCSI] libsas: kill sas_slave_destroy
Per commit 3e4ec344 "libata: kill ATA_FLAG_DISABLED" needing to set
ATA_DEV_NONE is a holdover from before libsas converted to the
"new-style" ata-eh.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:36:36 -06:00
Paul Gortmaker
09703660ed scsi: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required
For the basic SCSI infrastructure files that are exporting symbols
but not modules themselves, add in the basic export.h header file
to allow the exports.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:23 -04:00
Dan Williams
b50102d3e9 [SCSI] isci: atapi support
Based on original implementation from Jiangbi Liu and Maciej Trela.

ATAPI transfers happen in two-to-three stages.  The two stage atapi
commands are those that include a dma data transfer.  The data transfer
portion of these operations is handled by the hardware packet-dma
acceleration.  The three-stage commands do not have a data transfer and
are handled without hardware assistance in raw frame mode.

stage1: transmit host-to-device fis to notify the device of an incoming
atapi cdb.  Upon reception of the pio-setup-fis repost the task_context
to perform the dma transfer of the cdb+data (go to stage3), or repost
the task_context to transmit the cdb as a raw frame (go to stage 2).

stage2: wait for hardware notification of the cdb transmission and then
go to stage 3.

stage3: wait for the arrival of the terminating device-to-host fis and
terminate the command.

To keep the implementation simple we only support ATAPI packet-dma
protocol (for commands with data) to avoid needing to handle the data
transfer manually (like we do for SATA-PIO).  This may affect
compatibility for a small number of devices (see
ATA_HORKAGE_ATAPI_MOD16_DMA).

If the data-transfer underruns, or encounters an error the
device-to-host fis is expected to arrive in the unsolicited frame queue
to pass to libata for disposition.  However, in the DONE_UNEXP_FIS (data
underrun) case it appears we need to craft a response.  In the
DONE_REG_ERR case we do receive the UF and propagate it to libsas.

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:20:03 -05:00
Dan Williams
97a1420d12 [SCSI] libsas: dynamic queue depth
The queue-depth for libsas-attached devices initializes to 32 and can
only be increased manually via sysfs to a max of 64, while mpt2sas
attached devices initialize to 254 and dynamically float via the
midlayer ->change_queue_depth interface.

No performance regression was observed with this change on the isci
driver.

Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 12:36:43 -05:00
Dan Williams
f6e67035a9 [SCSI] libsas,libata: fix ->change_queue_{depth|type} for sata devices
Pass queue_depth change requests to libata, and prevent queue_type
changes for ATA devices.

Otherwise:
1/ we do not honor the libata specific restrictions on the queue depth
2/ libsas drivers that do not set sdev->tagged_supported are unable to
   change the queue_depth of ata devices via sysfs

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 12:30:30 -05:00
Christoph Hellwig
ac81c6a832 [SCSI] libsas: fix sas_queuecommand return values
->queuecommand must return either 0, or one of the SCSI_MLQUEUE_* return
values.  Non-transient errors are indicated by setting cmd->result before
calling ->scsi_done and returning 0.  Fix libsas to adhere to this calling
convention.  Note that the DID_ERROR for returns from the low-level driver
might not be correct for all cases, but it's the best we can do with
the current layering in libsas.  I also suspect that the pre-existing
handling of -SAS_QUEUE_FULL should really be SCSI_MLQUEUE_HOST_BUSY, but
I'll leave that for a separate change.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:13:46 -07:00
Christoph Hellwig
a923f756be [SCSI] libsas: reindent sas_queuecommand
Switch sas_queuecommand to a normal indentation and goto based error handling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:12:22 -07:00
Christoph Hellwig
92bd401ba7 [SCSI] libsas: sas_queuecommand doesnt need host_lock
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-30 12:09:41 -07:00
Dan Williams
3673f4bf6a [SCSI] libsas: check dev->gone before submitting sata i/o
Head off doomed-to-fail i/o in sas_queuecommand before sending it down
the ata path.

Before:
sd 7:0:0:0: [sdd] Synchronizing SCSI cache
ata8: no sense translation for status: 0x00
ata8: translated ATA stat/err 0x00/00 to SCSI SK/ASC/ASCQ 0xb/00/00
ata8.00: device reported invalid CHS sector 0
ata8: status=0x00 { }
ata8: no sense translation for status: 0x00
ata8: translated ATA stat/err 0x00/00 to SCSI SK/ASC/ASCQ 0xb/00/00
ata8.00: device reported invalid CHS sector 0
ata8: status=0x00 { }
ata8: no sense translation for status: 0x00
ata8: translated ATA stat/err 0x00/00 to SCSI SK/ASC/ASCQ 0xb/00/00
ata8.00: device reported invalid CHS sector 0
ata8: status=0x00 { }
sd 7:0:0:0: [sdd]  Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
sd 7:0:0:0: [sdd]  Sense Key : Aborted Command [current] [descriptor]
sd 7:0:0:0: [sdd]  Add. Sense: No additional sense information
sd 7:0:0:0: [sdd] Stopping disk

After:
sd 9:0:0:0: [sdd] Synchronizing SCSI cache
sd 9:0:0:0: [sdd]  Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK
sd 9:0:0:0: [sdd] Stopping disk
sd 9:0:0:0: [sdd] START_STOP FAILED
sd 9:0:0:0: [sdd]  Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK

This is a cosmetic change as sata i/o can still leak to a gone device,
but this addresses the nominal hotplug case when releasing the target.

Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
2011-05-26 22:49:33 -05:00
Linus Torvalds
c55d267de2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (170 commits)
  [SCSI] scsi_dh_rdac: Add MD36xxf into device list
  [SCSI] scsi_debug: add consecutive medium errors
  [SCSI] libsas: fix ata list corruption issue
  [SCSI] hpsa: export resettable host attribute
  [SCSI] hpsa: move device attributes to avoid forward declarations
  [SCSI] scsi_debug: Logical Block Provisioning (SBC3r26)
  [SCSI] sd: Logical Block Provisioning update
  [SCSI] Include protection operation in SCSI command trace
  [SCSI] hpsa: fix incorrect PCI IDs and add two new ones (2nd try)
  [SCSI] target: Fix volume size misreporting for volumes > 2TB
  [SCSI] bnx2fc: Broadcom FCoE offload driver
  [SCSI] fcoe: fix broken fcoe interface reset
  [SCSI] fcoe: precedence bug in fcoe_filter_frames()
  [SCSI] libfcoe: Remove stale fcoe-netdev entries
  [SCSI] libfcoe: Move FCOE_MTU definition from fcoe.h to libfcoe.h
  [SCSI] libfc: introduce __fc_fill_fc_hdr that accepts fc_hdr as an argument
  [SCSI] fcoe, libfc: initialize EM anchors list and then update npiv EMs
  [SCSI] Revert "[SCSI] libfc: fix exchange being deleted when the abort itself is timed out"
  [SCSI] libfc: Fixing a memory leak when destroying an interface
  [SCSI] megaraid_sas: Version and Changelog update
  ...

Fix up trivial conflicts due to whitespace differences in
drivers/scsi/libsas/{sas_ata.c,sas_scsi_host.c}
2011-03-17 17:54:40 -07:00
James Bottomley
00dd4998a6 libsas: convert to libata new error handler
The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling.  The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.

Finally, activate the port recovery of the libata error handler for
each port known to the host.  This is somewhat suboptimal, since that
port may not need recovering, but given the current architecture of
the libata error handler, it's the only way; and the spurious
activation is harmless.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2011-03-02 02:36:45 -05:00
James Bottomley
c299190b93 [SCSI] libsas: convert to libata new error handler
The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling.  The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.

Finally, activate the port recovery of the libata error handler for
each port known to the host.  This is somewhat suboptimal, since that
port may not need recovering, but given the current architecture of
the libata error handler, it's the only way; and the spurious
activation is harmless.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-13 13:17:46 -06:00
James Bottomley
9ee91f7fb5 [SCSI] libsas: fix runaway error handler problem
libsas makes use of scsi_schedule_eh() but forgets to clear the
host_eh_scheduled flag in its error handling routine.  Because of this,
the error handler thread never gets to sleep; it's constantly awake and
trying to run the error routine leading to console spew and inability to
run anything else (at least on a UP system).  The fix is to clear the
flag as we splice the work queue.

Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-24 11:52:33 -06:00
Jeff Garzik
b27dcfb067 [libata] avoid needlessly passing around ptr to SCSI completion func
It's stored in struct scsi_cmnd->scsi_done, making several 'done'
parameters to functions redundant.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2011-01-05 19:43:22 -05:00
Jeff Garzik
f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00