The total ata xfer length may not be calculated properly, in that we do
not use the proper method to get an sg element dma length.

According to the code comment, sg_dma_len() should be used after
dma_map_sg() is called.

This issue was found by turning on the SMMUv3 in front of the hisi_sas
controller in hip07. Multiple sg elements were being combined into a
single element, but the original first element length was being use as
the total xfer length.

Cc: <stable@vger.kernel.org>
Fixes: ff2aeb1e ("libata: convert to chained sg")
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

And require all drivers that want to support BLOCK_PC to allocate it
as the first thing of their private data.  To support this the legacy
IDE and BSG code is switched to set cmd_size on their queues to let
the block layer allocate the additional space.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

A freed task has been assigned to ->lldd_task when lldd_execute_task()
failed in sas_ata_qc_issue(), and access of ->lldd_task will cause an
oops:

Call trace:
[<ffffffc000641f64>] sas_ata_post_internal+0x6c/0x150
[<ffffffc0006c0d64>] ata_exec_internal_sg+0x32c/0x588
[<ffffffc0006c1048>] ata_exec_internal+0x88/0xe8
[<ffffffc0006c13b4>] ata_dev_read_id+0x204/0x5e0
[<ffffffc0006c17f0>] ata_dev_reread_id+0x60/0xc8
[<ffffffc0006c3098>] ata_dev_revalidate+0x88/0x1e0
[<ffffffc0006cf828>] ata_eh_recover+0xcf8/0x13a8
[<ffffffc0006d075c>] ata_do_eh+0x5c/0xe0
[<ffffffc0006d0828>] ata_std_error_handler+0x48/0x98
[<ffffffc0006d042c>] ata_scsi_port_error_handler+0x474/0x658
[<ffffffc000641b78>] async_sas_ata_eh+0x50/0x80
[<ffffffc0000ca664>] async_run_entry_fn+0x64/0x180
[<ffffffc0000c085c>] process_one_work+0x164/0x438
[<ffffffc0000c0c74>] worker_thread+0x144/0x4b0
[<ffffffc0000c70fc>] kthread+0xfc/0x110

Fix this by reassigning NULL to ->lldd_task in error path.
Signed-off-by: NWei Fang <fangwei1@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Use accessors instead of the raw protocol value.
Signed-off-by: NHannes Reinecke <hare@suse.com>
[hch: trivial cleanup of the ata_task assignments]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

Define the NCQ NON DATA command and update libsas to handle it
correctly.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Update libsas and dependent drivers to handle FPDMA
SEND/RECEIVE correctly.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

SAS controller has its own tag allocation, which doesn't directly match to ATA
tag, so SAS and SATA have different code path for ata tags. Originally we use
port->scsi_host (98bd4be1) to destinguish SAS controller, but libsas set
->scsi_host too, so we can't use it for the destinguish, we add a new flag for
this purpose.

Without this patch, the following oops can happen because scsi-mq uses
a host-wide tag map shared among all devices with some integer tag
values >= ATA_MAX_QUEUE.  These unexpectedly high tag values cause
__ata_qc_from_tag() to return NULL, which is then dereferenced in
ata_qc_new_init().

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
  IP: [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
  PGD 32adf0067 PUD 32adf1067 PMD 0
  Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
  Modules linked in: iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi igb
  i2c_algo_bit ptp pps_core pm80xx libsas scsi_transport_sas sg coretemp
  eeprom w83795 i2c_i801
  CPU: 4 PID: 1450 Comm: cydiskbench Not tainted 4.0.0-rc3 #1
  Hardware name: Supermicro X8DTH-i/6/iF/6F/X8DTH, BIOS 2.1b       05/04/12
  task: ffff8800ba86d500 ti: ffff88032a064000 task.ti: ffff88032a064000
  RIP: 0010:[<ffffffff804fd46e>]  [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
  RSP: 0018:ffff88032a067858  EFLAGS: 00010046
  RAX: 0000000000000000 RBX: ffff8800ba0d2230 RCX: 000000000000002a
  RDX: ffffffff80505ae0 RSI: 0000000000000020 RDI: ffff8800ba0d2230
  RBP: ffff88032a067868 R08: 0000000000000201 R09: 0000000000000001
  R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800ba0d0000
  R13: ffff8800ba0d2230 R14: ffffffff80505ae0 R15: ffff8800ba0d0000
  FS:  0000000041223950(0063) GS:ffff88033e480000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 0000000000000058 CR3: 000000032a0a3000 CR4: 00000000000006e0
  Stack:
   ffff880329eee758 ffff880329eee758 ffff88032a0678a8 ffffffff80502dad
   ffff8800ba167978 ffff880329eee758 ffff88032bf9c520 ffff8800ba167978
   ffff88032bf9c520 ffff88032bf9a290 ffff88032a0678b8 ffffffff80506909
  Call Trace:
   [<ffffffff80502dad>] ata_scsi_translate+0x3d/0x1b0
   [<ffffffff80506909>] ata_sas_queuecmd+0x149/0x2a0
   [<ffffffffa0046650>] sas_queuecommand+0xa0/0x1f0 [libsas]
   [<ffffffff804ea544>] scsi_dispatch_cmd+0xd4/0x1a0
   [<ffffffff804eb50f>] scsi_queue_rq+0x66f/0x7f0
   [<ffffffff803e5098>] __blk_mq_run_hw_queue+0x208/0x3f0
   [<ffffffff803e54b8>] blk_mq_run_hw_queue+0x88/0xc0
   [<ffffffff803e5c74>] blk_mq_insert_request+0xc4/0x130
   [<ffffffff803e0b63>] blk_execute_rq_nowait+0x73/0x160
   [<ffffffffa0023fca>] sg_common_write+0x3da/0x720 [sg]
   [<ffffffffa0025100>] sg_new_write+0x250/0x360 [sg]
   [<ffffffffa0025feb>] sg_write+0x13b/0x450 [sg]
   [<ffffffff8032ec91>] vfs_write+0xd1/0x1b0
   [<ffffffff8032ee54>] SyS_write+0x54/0xc0
   [<ffffffff80689932>] system_call_fastpath+0x12/0x17

tj: updated description.

Fixes: 12cb5ce1 ("libata: use blk taging")
Reported-and-tested-by: NTony Battersby <tonyb@cybernetics.com>
Signed-off-by: NShaohua Li <shli@fb.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

This crash was reported:

[  366.947370] sd 3:0:1:0: [sdb] Spinning up disk....
[  368.804046] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  368.804072] IP: [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.804098] PGD 0
[  368.804114] Oops: 0002 [#1] SMP
[  368.804143] CPU 1
[  368.804151] Modules linked in: sg netconsole s3g(PO) uinput joydev hid_multitouch usbhid hid snd_hda_codec_via cpufreq_userspace cpufreq_powersave cpufreq_stats uhci_hcd cpufreq_conservative snd_hda_intel snd_hda_codec snd_hwdep snd_pcm sdhci_pci snd_page_alloc sdhci snd_timer snd psmouse evdev serio_raw pcspkr soundcore xhci_hcd shpchp s3g_drm(O) mvsas mmc_core ahci libahci drm i2c_core acpi_cpufreq mperf video processor button thermal_sys dm_dmirror exfat_fs exfat_core dm_zcache dm_mod padlock_aes aes_generic padlock_sha iscsi_target_mod target_core_mod configfs sswipe libsas libata scsi_transport_sas picdev via_cputemp hwmon_vid fuse parport_pc ppdev lp parport autofs4 ext4 crc16 mbcache jbd2 sd_mod crc_t10dif usb_storage scsi_mod ehci_hcd usbcore usb_common
[  368.804749]
[  368.804764] Pid: 392, comm: kworker/u:3 Tainted: P        W  O 3.4.87-logicube-ng.22 #1 To be filled by O.E.M. To be filled by O.E.M./EPIA-M920
[  368.804802] RIP: 0010:[<ffffffff81358457>]  [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.804827] RSP: 0018:ffff880117001cc0  EFLAGS: 00010246
[  368.804842] RAX: 0000000000000000 RBX: ffff8801185030d0 RCX: ffff88008edcb420
[  368.804857] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8801185030d4
[  368.804873] RBP: ffff8801181531c0 R08: 0000000000000020 R09: 00000000fffffffe
[  368.804885] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801185030d4
[  368.804899] R13: 0000000000000002 R14: ffff880117001fd8 R15: ffff8801185030d8
[  368.804916] FS:  0000000000000000(0000) GS:ffff88011fc80000(0000) knlGS:0000000000000000
[  368.804931] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  368.804946] CR2: 0000000000000000 CR3: 000000000160b000 CR4: 00000000000006e0
[  368.804962] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  368.804978] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  368.804995] Process kworker/u:3 (pid: 392, threadinfo ffff880117000000, task ffff8801181531c0)
[  368.805009] Stack:
[  368.805017]  ffff8801185030d8 0000000000000000 ffffffff8161ddf0 ffffffff81056f7c
[  368.805062]  000000000000b503 ffff8801185030d0 ffff880118503000 0000000000000000
[  368.805100]  ffff8801185030d0 ffff8801188b8000 ffff88008edcb420 ffffffff813583ac
[  368.805135] Call Trace:
[  368.805153]  [<ffffffff81056f7c>] ? up+0xb/0x33
[  368.805168]  [<ffffffff813583ac>] ? mutex_lock+0x16/0x25
[  368.805194]  [<ffffffffa018c414>] ? smp_execute_task+0x4e/0x222 [libsas]
[  368.805217]  [<ffffffffa018ce1c>] ? sas_find_bcast_dev+0x3c/0x15d [libsas]
[  368.805240]  [<ffffffffa018ce4f>] ? sas_find_bcast_dev+0x6f/0x15d [libsas]
[  368.805264]  [<ffffffffa018e989>] ? sas_ex_revalidate_domain+0x37/0x2ec [libsas]
[  368.805280]  [<ffffffff81355a2a>] ? printk+0x43/0x48
[  368.805296]  [<ffffffff81359a65>] ? _raw_spin_unlock_irqrestore+0xc/0xd
[  368.805318]  [<ffffffffa018b767>] ? sas_revalidate_domain+0x85/0xb6 [libsas]
[  368.805336]  [<ffffffff8104e5d9>] ? process_one_work+0x151/0x27c
[  368.805351]  [<ffffffff8104f6cd>] ? worker_thread+0xbb/0x152
[  368.805366]  [<ffffffff8104f612>] ? manage_workers.isra.29+0x163/0x163
[  368.805382]  [<ffffffff81052c4e>] ? kthread+0x79/0x81
[  368.805399]  [<ffffffff8135fea4>] ? kernel_thread_helper+0x4/0x10
[  368.805416]  [<ffffffff81052bd5>] ? kthread_flush_work_fn+0x9/0x9
[  368.805431]  [<ffffffff8135fea0>] ? gs_change+0x13/0x13
[  368.805442] Code: 83 7d 30 63 7e 04 f3 90 eb ab 4c 8d 63 04 4c 8d 7b 08 4c 89 e7 e8 fa 15 00 00 48 8b 43 10 4c 89 3c 24 48 89 63 10 48 89 44 24 08 <48> 89 20 83 c8 ff 48 89 6c 24 10 87 03 ff c8 74 35 4d 89 ee 41
[  368.805851] RIP  [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[  368.805877]  RSP <ffff880117001cc0>
[  368.805886] CR2: 0000000000000000
[  368.805899] ---[ end trace b720682065d8f4cc ]---

It's directly caused by 89d3cf6a [SCSI] libsas: add mutex for SMP task
execution, but shows a deeper cause: expander functions expect to be able to
cast to and treat domain devices as expanders.  The correct fix is to only do
expander discover when we know we've got an expander device to avoid wrongly
casting a non-expander device.
Reported-by: NPraveen Murali <pmurali@logicube.com>
Tested-by: NPraveen Murali <pmurali@logicube.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com
Reviewed-by: NHannes Reinecke <hare@suse.de>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Acked-by: NDan Williams <dan.j.williams@intel.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NVenkatesh Srinivas <venkateshs@google.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>

Use the ata device class from libata in libsas instead of checking
the supported command set and switch to using ata_dev_classify()
instead of our own method.

Cc: Tejun Heo <tj@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

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: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NWebb Scales <webbnh@hp.com>
Acked-by: NJens Axboe <axboe@kernel.dk>
Tested-by: NBart Van Assche <bvanassche@acm.org>
Tested-by: NRobert Elliott <elliott@hp.com>

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: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@infradead.org>
Reviewed-by: NEwan Milne <emilne@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Tejun says:
  "At least for libata, worrying about suspend/resume failures don't make
   whole lot of sense.  If suspend failed, just proceed with suspend.  If
   the device can't be woken up afterwards, that's that.  There isn't
   anything we could have done differently anyway.  The same for resume, if
   spinup fails, the device is dud and the following commands will invoke
   EH actions and will eventually fail.  Again, there really isn't any
   *choice* to make.  Just making sure the errors are handled gracefully
   (ie. don't crash) and the following commands are handled correctly
   should be enough."

The only libata user that actually cares about the result from a suspend
operation is libsas.  However, it only cares about whether queuing a new
operation collides with an in-flight one.  All libsas does with the
error is retry, but we can just let libata wait for the previous
operation before continuing.

Other cleanups include:
1/ Unifying all ata port pm operations on an ata_port_pm_ prefix
2/ Marking all ata port pm helper routines as returning void, only
   ata_port_pm_ entry points need to fake a 0 return value.
3/ Killing ata_port_{suspend|resume}_common() in favor of calling
   ata_port_request_pm() directly
4/ Killing the wrappers that just do a to_ata_port() conversion
5/ Clearly marking the entry points that do async operations with an
  _async suffix.

Reference: http://marc.info/?l=linux-scsi&m=138995409532286&w=2

Cc: Phillip Susi <psusi@ubuntu.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NTodd Brandt <todd.e.brandt@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

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: NXun Ni <xun.ni@intel.com>
Tested-by: NNelson Cheng <nelson.cheng@intel.com>
Acked-by: NLukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Since commit 110dd8f1 "[SCSI] libsas: fix scr_read/write users and
update the libata documentation" we have been passing pmp=1 and is_cmd=0
to ata_tf_to_fis().  Praveen reports that eSATA attached drives do not
discover correctly.  His investigation found that the BIOS was passing
pmp=0 while Linux was passing pmp=1 and failing to discover the drives.
Update libsas to follow the libata example of pulling the pmp setting
from the ata_link and correct is_cmd to be 1 since all tf's submitted
through ->qc_issue are commands.  Presumably libsas lldds do not care
about is_cmd as they have sideband mechanisms to perform link
management.

http://marc.info/?l=linux-scsi&m=138179681726990

[jejb: checkpatch fix]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reported-by: NPraveen Murali <pmurali@logicube.com>
Tested-by: NPraveen Murali <pmurali@logicube.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

When we start sharing biovecs, keeping bi_vcnt accurate for splits is
going to be error prone - and unnecessary, if we refactor some code.

So bio_segments() has to go - but most of the existing users just needed
to know if the bio had multiple segments, which is easier - add a
bio_multiple_segments() for them.

(Two of the current uses of bio_segments() are going to go away in a
couple patches, but the current implementation of bio_segments() is
unsafe as soon as we start doing driver conversions for immutable
biovecs - so implement a dumb version for bisectability, it'll go away
in a couple patches)
Signed-off-by: NKent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Neil Brown <neilb@suse.de>
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>

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: NJames Bottomley <JBottomley@Parallels.com>

These enums have been separate since the dawn of SAS, mainly because the
latter is a procotol only enum and the former includes additional state
for libsas.  The dichotomy causes endless confusion about which one you
should use where and leads to pointless warnings like this:

drivers/scsi/mvsas/mv_sas.c: In function 'mvs_update_phyinfo':
drivers/scsi/mvsas/mv_sas.c:1162:34: warning: comparison between 'enum sas_device_type' and 'enum sas_dev_type' [-Wenum-compare]

Fix by eliminating one of them.  The one kept is effectively the sas.h
one, but call it sas_device_type and make sure the enums are all
properly namespaced with the SAS_ prefix.
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

If a result of the SMP discover function is PHY VACANT,
the content of discover response structure (dr) is not valid.
It sometimes happens that dr->attached_sas_addr can contain
even SAS address of other phy. In such case an invalid phy
is created, what causes NULL pointer dereference during
destruction of expander's phys.

So if a result of SMP function is PHY VACANT, the content of discover
response structure (dr) must not be copied to phy structure.

This patch fixes the following bug:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffff811c9002>] sysfs_find_dirent+0x12/0x90
Call Trace:
  [<ffffffff811c95f5>] sysfs_get_dirent+0x35/0x80
  [<ffffffff811cb55e>] sysfs_unmerge_group+0x1e/0xb0
  [<ffffffff813329f4>] dpm_sysfs_remove+0x24/0x90
  [<ffffffff8132b0f4>] device_del+0x44/0x1d0
  [<ffffffffa016fc59>] sas_rphy_delete+0x9/0x20 [scsi_transport_sas]
  [<ffffffffa01a16f6>] sas_destruct_devices+0xe6/0x110 [libsas]
  [<ffffffff8107ac7c>] process_one_work+0x16c/0x350
  [<ffffffff8107d84a>] worker_thread+0x17a/0x410
  [<ffffffff81081b76>] kthread+0x96/0xa0
  [<ffffffff81464944>] kernel_thread_helper+0x4/0x10
Signed-off-by: NLukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: NPawel Baldysiak <pawel.baldysiak@intel.com>
Reviewed-by: NMaciej Patelczyk <maciej.patelczyk@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

In fact the disc_resp buffer will be overwrite by smp response, so we never
found this typo, correct it by using the right one.
Signed-off-by: NJohn Gong <john_gong@usish.com>
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

More prep work for immutable bvecs/effecient bio splitting - usage of
bi_vcnt has to be auditing, so getting rid of all the unnecessary usage
makes that easier.

Plus, bio_segments() is really what this code wanted, as it respects the
current value of bi_idx.
Signed-off-by: NKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Eric Moore <Eric.Moore@lsi.com>
CC: "James E.J. Bottomley" <JBottomley@parallels.com>
CC: linux-scsi@vger.kernel.org

Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

libsas and ipr pass flags to ata_host_init that are meant for the port.

ata_host flags:
	ATA_HOST_SIMPLEX	= (1 << 0),	/* Host is simplex, one DMA channel per host only */
	ATA_HOST_STARTED	= (1 << 1),	/* Host started */
	ATA_HOST_PARALLEL_SCAN	= (1 << 2),	/* Ports on this host can be scanned in parallel */
	ATA_HOST_IGNORE_ATA	= (1 << 3),	/* Ignore ATA devices on this host. */

flags passed by libsas:
	ATA_FLAG_SATA		= (1 << 1),
	ATA_FLAG_PIO_DMA	= (1 << 7), /* PIO cmds via DMA */
	ATA_FLAG_NCQ		= (1 << 10), /* host supports NCQ */

The only one that aliases is ATA_HOST_STARTED which is a 'don't care' in
the libsas and ipr cases since ata_hosts from these sources are not
registered with libata.
Reported-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NBrian King <brking@us.ibm.com>
Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

libsas power management routines to suspend and recover the sas domain
based on a model where the lldd is allowed and expected to be
"forgetful".

sas_suspend_ha - disable event processing allowing the lldd to take down
                 links without concern for causing hotplug events.
                 Regardless of whether the lldd actually posts link down
                 messages libsas notifies the lldd that all
                 domain_devices are gone.

sas_prep_resume_ha - on the way back up before the lldd starts link
                     training clean out any spurious events that were
                     generated on the way down, and re-enable event
                     processing

sas_resume_ha - after the lldd has started and decided that all phys
		have posted link-up events this routine is called to let
		libsas start it's own timeout of any phys that did not
		resume.  After the timeout an lldd can cancel the
                phy teardown by posting a link-up event.

Storage for ex_change_count (u16) and phy_change_count (u8) are changed
to int so they can be set to -1 to indicate 'invalidated'.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NJacek Danecki <jacek.danecki@intel.com>
Tested-by: NMaciej Patelczyk <maciej.patelczyk@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This is in preparation for teaching async_synchronize_full() to sync all
pending async work, and not just on the async_running domain.  This
conversion is functionally equivalent, just embedding the existing list
in a new async_domain type.

The .registered attribute is used in a later patch to distinguish
between domains that want to be flushed by async_synchronize_full()
versus those that only expect async_synchronize_{full|cookie}_domain to
be used for flushing.

[jejb: add async.h to scsi_priv.h for struct async_domain]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NArjan van de Ven <arjan@linux.intel.com>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: NEldad Zack <eldad@fogrefinery.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NJack Wang <jack_wang@usish.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

On the way to add a new sata_device field, noticed that libsas is
carrying port multiplier infrastructure that is explicitly disabled by
sas_discover_sata().  The aic94xx touches the unused port_no, so leave
that field in case there was some use for it.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

commit 198439e4 [SCSI] libsas: do not set res = 0 in sas_ex_discover_dev()
commit 19252de6 [SCSI] libsas: fix wide port hotplug issues

The above commits seem to have confused the return value of
sas_ex_discover_dev which is non-zero on failure and
sas_ex_join_wide_port which just indicates short circuiting discovery on
already established ports.  The result is random discovery failures
depending on configuration.

Calls to sas_ex_join_wide_port are the source of the trouble as its
return value is errantly assigned to 'res'.  Convert it to bool and stop
returning its result up the stack.

Cc: <stable@vger.kernel.org>
Tested-by: NDan Melnic <dan.melnic@amd.com>
Reported-by: NDan Melnic <dan.melnic@amd.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Continue running revalidation until no more broadcast devices are
discovered.  Fixes cases where re-discovery completes too early in a
domain with multiple expanders with pending re-discovery events.
Servicing BCNs can get backed up behind error recovery.

Cc: <stable@vger.kernel.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The discovery function "sas_rediscover_dev" had two bugs: 1) it did
not pay attention to the return status from the SMP task execution;
2) the stack variable used for the returned SAS address was compared
against 0 without being initialized.
Signed-off-by: NJeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NJacek Danecki <jacek.danecki@intel.com>
[jacek: modify pm8001_I_T_nexus_reset to return -ENODEV]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

When recovering failed eh-cmnds let the lldd attempt an abort via
scsi_abort_eh_cmnd before escalating.
Reviewed-by: NJacek Danecki <jacek.danecki@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>