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>

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

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

When an lldd invokes ->notify_port_event() it can trigger a chain of libsas
events to:

  1/ form the port and find the direct attached device

  2/ if the attached device is an expander perform domain discovery

A call to flush_workqueue() will only flush the initial port formation work.
Currently libsas users need to call scsi_flush_work() up to the max depth of
chain (which will grow from 2 to 3 when ata discovery is moved to its own
discovery event).  Instead of open coding multiple calls switch to use
drain_workqueue() to flush sas work.

drain_workqueue() does not handle new work submitted during the drain so
libsas needs a bit of infrastructure to hold off unchained work submissions
while a drain is in flight.  A lldd ->notify() event is considered 'unchained'
while a sas_discover_event() is 'chained'.  As Tejun notes:

  "For now, I think it would be best to add private wrapper in libsas to
   support deferring unchained work items while draining."
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

IO_XFER_ERROR_BREAK and IO_XFER_OPEN_RETRY_TIMEOUT are deficient of the
required actions as outlined in the programming manual for the pm8001. Due to
the overlapping code requirements of these recovery responses, we found it
necessary to bundle them together into one patch.

When a break is received during the command phase (ssp_completion), this is a
result of a timeout or interruption on the bus. Logic suggests that we should
retry the command.

When a break is received during the data-phase (ssp_event), the task must be
aborted on the target or it will retain a data-phase lock turning the target
reticent to all future media commands yet will successfully respond to TUR,
INQUIRY and ABORT leading eventually to target failure through several
abort-cycle loops.

The open retry interval is exceedingly short resulting in occasional target
drop-off during expander resets or when targets push-back during bad-block
remapping. Increased effective timeout from 130ms to 1.5 seconds for each try
so as to trigger after the administrative inquiry/tur timeout in the scsi
subsystem to keep error-recovery harmonics to a minimum.

When an open retry timeout event is received, the action required by the
targets is to issue an abort for the outstanding command then logic suggests
we retry the command as this state is usually an indication of a credit block
or busy condition on the target.

We hijacked the pm8001_handle_event work queue handler so that it will handle
task as an argument instead of device for the workers in support of the
deferred handling outlined above.

Moderate to Heavy bad-path testing on a 2.6.32 vintage kernel, compile-testing
on scsi-misc-2.6 kernel ...
Signed-off-by: NMark Salyzyn <mark_salyzyn@xyratex.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Jack noticed I dropped a patch fragment associated with a flags automatic
variable in mpi_set_phys_g3_with_ssc (ooops) and that the pre-emptive locking
that piggy-backed this patch was not in-fact necessary because of underlying
atomic accesses to the hardware. Here is the updated patch fixing these two
issues.

The pm8001 driver is missing the FUNC_GET_EVENTS handler in the phy control
function. Since the pm8001_bar4_shift function was not designed to be called
at runtime, added locking surrounding the adjustment for all accesses.
Signed-off-by: NMark Salyzyn <mark_salyzyn@xyratex.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

pm8001_phy_control PHY_FUNC_HARD_RESET locks up on second try via
smp_phy_control because response HW_EVENT_PHY_START_STATUS fails to complete
previous command. The PM8001F_RUN_TIME flag is not treated as a bit, but a
state in all readers, yet once we are operational or in the run time state,
the flags use a bit-set operation.
Signed-off-by: NMark Salyzyn <mark_salyzyn@xyratex.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Allow the sas-transport-class to update events for local phys via a new
PHY_FUNC_GET_EVENTS command to ->lldd_control_phy().  Fixup drivers that
are not prepared for new enum phy_func values, and unify
->lldd_control_phy() error codes.

These are the SAS defined phy events that are reported in a
smp-report-phy-error-log command:
 * /sys/class/sas_phy/<phyX>/invalid_dword_count
 * /sys/class/sas_phy/<phyX>/running_disparity_error_count
 * /sys/class/sas_phy/<phyX>/loss_of_dword_sync_count
 * /sys/class/sas_phy/<phyX>/phy_reset_problem_count
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Code Inspection: found two missing break directives. First one will
result in not retrying an a task that report
IO_OPEN_CNX_ERROR_HW_RESOURCE_BUSY, the second will result in cosmetic
debug printk conflicting statement stutter. Because checkpatch.pl came
up with a warning regarding unnecessary space before a newline on one of
the fragments associated with the diff context, I took the liberty of
fixing all the cases of this issue in the pair of files touched by this
defect. These cosmetic changes hide the break changes :-(

To help focus, break changes are in pm8001_hwi.c fragment line 1649 for
the IO_OPEN_CNX_ERROR_HW_RESOURCE_BUSY case statement and pm8001_sas.c
line 1000 deals with the conflicting debug print stutter.
Signed-off-by: NMark Salyzyn <mark_salyzyn@us.xyratex.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

On the pm8001, when a device is in the process of going away (device
power off or hot plug), depending on the timing, the driver would return
SAS_PHY_DOWN as the return value to the queuecommand DEV_IS_GONE logic.
The net result is an near infinite retry (especially if SAS debugging is
enabled), the logs will fill with:

kernel: mpi_ssp_completion 2119:e21:SSP IO status 0x13 tag 0xcc1c0000
dlen=90 param=0xe
kernel: wwn=5000c50034069e86  cdb=12 00 00 00 5a 00 00 00 00 00 00 00 00
00 00 00
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
kernel: sas: lldd_execute_task returned: 138
. . .

This patch changes to leverage the port_attached logic to complete the
command with a status of PHY_DOWN so that the disposition can be handled
immediately and correctly.
Signed-off-by: NMark Salyzyn <mark_salyzyn@us.xyratex.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

libsas handles:
1/ limiting ata scanning to lun0
2/ changes to /sys/block/<sdX>/device/queue_depth for ata devices

libata handles turning off ncq globally via kernel command line
(libata.force=noncq) or sysfs (echo 1 >
/sys/block/<sdX>/device/queue_depth).  A lldd specific compile option is
not necessary.

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

Now that isci has added a 3rd open coded user of this functionality just
share the libsas version.
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>

We have two separate definitions for identical constants with nearly the
same name.  One comes from the generic headers in scsi.h; the other is
an enum in libsas.h ... it's causing confusion about which one is
correct (fortunately they both are).

Fix this by eliminating the libsas.h duplicate
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

In the original code we dereferenced "pm8001_dev" before checking if it
was null.  This patch moves the dereference inside the condition.

This was found by a static checker (smatch).  I looked, but I couldn't
tell if "pm8001_dev" dev was ever actually null.  The approach in this
patch seemed like the safest response.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.
Signed-off-by: NDaniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add more data to printk's, add some spaces around arithmetic ops and
improve comments.
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Enhance error handle for IO patch, when the port is down, fast return phy
down for task.
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Allocate right size for bitmap tag,fix error goto and cleanup print
message and undocable commemts. patch attached.
Signed-off-by: NLindar Liu <lindar_liu@usish.com>
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NLindar Liu <lindar_liu@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This driver supports PMC-Sierra PCIe SAS/SATA 8x6G SPC 8001 chip based
host adapters.
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NLindar Liu <lindar_liu@usish.com>
Signed-off-by: NTom Peng <tom_peng@usish.com>
Signed-off-by: NKevin Ao <aoqingyun@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>