Move EXPORT_SYMBOL_GPL()s close to exported code like it is
done in other kernel subsystems. As a nice side effect this
results in the removal of few ifdefs.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In commit 7634ccd2 ("libata: maintainership update") from 2018
Jens has officially taken over libata maintainership from Tejun so
remove stale information from core libata code.
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

ZAC support added sense data requesting on error for both ZAC and ATA
devices. This seems to cause erratic error handling behaviors on some
SSDs where the device reports sense data availability and then
delivers the wrong content making EH take the wrong actions.  The
failure mode was sporadic on a LITE-ON ssd and couldn't be reliably
reproduced.

There is no value in requesting sense data from non-ZAC ATA devices
while there's a significant risk of introducing EH misbehaviors which
are difficult to reproduce and fix.  Let's do the sense data dancing
only for ZAC devices.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Tested-by: NMasato Suzuki <masato.suzuki@wdc.com>
Reviewed-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version this program is distributed in the hope that it will
  be useful but without any warranty without even the implied warranty
  of merchantability or fitness for a particular purpose see the gnu
  general public license for more details you should have received a
  copy of the gnu general public license along with this program see
  the file copying if not write to the free software foundation 675
  mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 52 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NJilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: NSteve Winslow <swinslow@gmail.com>
Reviewed-by: NKate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154042.342335923@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is nothing it could synchronize against, so don't go through
the pains of acquiring the lock.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NTejun Heo <tj@kernel.org>

As far as I can tell this function can't even be called any more, given
that ATA implements its own eh_strategy_handler with ata_scsi_error, which
never calls ->eh_timed_out.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Bump the internal tag to 32, instead of stealing the last tag in
our regular command space. This works just fine, since we don't
actually need a separate hardware tag for this. Internal commands
cannot coexist with NCQ commands.

As a bonus, we get rid of the special casing of what tag to use
for the internal command.

This is in preparation for utilizing all 32 commands for normal IO.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NTejun Heo <tj@kernel.org>

In a few spots we iterate to ATA_MAX_QUEUE -1, including internal
knowledge that the last tag is the internal tag. Remove this
assumption.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NTejun Heo <tj@kernel.org>

For failed commands with valid sense data (e.g. NCQ commands),
scsi_check_sense() is used in ata_analyze_tf() to determine if the
command can be retried. In such case, rely on this decision and ignore
the command error mask based decision done in ata_worth_retry().

This fixes useless retries of commands such as unaligned writes on zoned
disks (TYPE_ZAC).
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Currently, libata ignores requests RQF_QUIET flag and print error
messages for failed commands, regardless if this flag is set in the
command request. Fix this by introducing the ata_eh_quiet() function and
using this function in ata_eh_link_autopsy() to determine if the EH
context should be quiet. This works by counting the number of failed
commands and the number of commands with the quiet flag set. If both
numbers are equal, the the EH context can be set to quiet and all error
messages suppressed. Otherwise, only the error messages for the failed
commands are suppressed and the link Emask and irq_stat messages printed.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Add proper error string output for ATA_ERR_NCQ and ATA_ERR_NODEV_HINT
instead of returning "unknown error".
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

__printf is useful to verify format and arguments. Remove the following
warning (with W=1):

  drivers/ata/libata-eh.c:183:10: warning: function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
Signed-off-by: NMathieu Malaterre <malat@debian.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

We've got a kernel panic when using sata disk with sas controller:

[115946.152283] Unable to handle kernel NULL pointer dereference at virtual address 000007d8
[115946.223963] CPU: 0 PID: 22175 Comm: kworker/0:1 Tainted: G   W OEL  4.14.0 #1
[115946.232925] Workqueue: events ata_scsi_hotplug
[115946.237938] task: ffff8021ee50b180 task.stack: ffff00000d5d0000
[115946.244717] PC is at sas_find_dev_by_rphy+0x44/0x114
[115946.250224] LR is at sas_find_dev_by_rphy+0x3c/0x114
......
[115946.355701] Process kworker/0:1 (pid: 22175, stack limit = 0xffff00000d5d0000)
[115946.363369] Call trace:
[115946.456356] [<ffff000008878a9c>] sas_find_dev_by_rphy+0x44/0x114
[115946.462908] [<ffff000008878b8c>] sas_target_alloc+0x20/0x5c
[115946.469408] [<ffff00000885a31c>] scsi_alloc_target+0x250/0x308
[115946.475781] [<ffff00000885ba30>] __scsi_add_device+0xb0/0x154
[115946.481991] [<ffff0000088b520c>] ata_scsi_scan_host+0x180/0x218
[115946.488367] [<ffff0000088b53d8>] ata_scsi_hotplug+0xb0/0xcc
[115946.494801] [<ffff0000080ebd70>] process_one_work+0x144/0x390
[115946.501115] [<ffff0000080ec100>] worker_thread+0x144/0x418
[115946.507093] [<ffff0000080f2c98>] kthread+0x10c/0x138
[115946.512792] [<ffff0000080855dc>] ret_from_fork+0x10/0x18

We found that Ding Xiang has reported a similar bug before:
https://patchwork.kernel.org/patch/9179817/

And this bug still exists in mainline. Since libsas handles hotplug and
device adding/removing itself, do not need to schedule ata hot plug task
here if it is a sas host.
Signed-off-by: NJason Yan <yanaijie@huawei.com>
Cc: Ding Xiang <dingxiang@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: NTejun Heo <tj@kernel.org>

When tracing ata link error event, the kernel crashes when the disk is
removed due to NULL pointer access by trace_ata_eh_link_autopsy API.
This occurs as the dev is NULL when the disk disappeared. This patch
fixes this crash by calling trace_ata_eh_link_autopsy only if "dev"
is not NULL.

v2 changes:
 Removed direct passing "link" pointer instead of "dev" in trace API.
Signed-off-by: NRameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Fixes: 255c03d1 ("libata: Add tracepoints")
Cc: stable@vger.kernel.org # v4.1+

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

In cases where a "drop through" comment was already in place, I replaced
it  with a proper "fall through" comment, which is what GCC is expecting
to find.
Signed-off-by: NGustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: linux-ide@vger.kernel.org
Link: https://lkml.kernel.org/r/20171005004842.GA23011@beast

As described by Matthew Garret quite a while back:
https://mjg59.dreamwidth.org/34868.html

Intel CPUs starting with the Haswell generation need SATA links to power
down for the "package" part of the CPU to reach low power-states like
PC7 / P8 which bring a significant power-saving with them.

The default max_performance lpm policy does not allow for these high
PC states, both the medium_power and min_power policies do allow this.

The min_power policy saves significantly more power, but there are some
reports of some disks / SSDs not liking min_power leading to system
crashes and in some cases even data corruption has been reported.

Matthew has found a document documenting the default settings of
Intel's IRST Windows driver with which most laptops ship:
https://www-ssl.intel.com/content/dam/doc/reference-guide/sata-devices-implementation-recommendations.pdf

Matthew wrote a patch changing med_power to match those defaults, but
that never got anywhere as some people where reporting issues with the
patch-set that patch was a part of.

This commit is another attempt to make the default IRST driver settings
available under Linux, but instead of changing medium_power and
potentially introducing regressions, this commit adds a new
med_power_with_dipm setting which is identical to the existing
medium_power accept that it enables dipm on top, which makes it match
the Windows IRST driver settings, which should hopefully be safe to
use on most devices.

The med_power_with_dipm setting is close to min_power, except that:
a) It does not use host-initiated slumber mode (ASP not set),
   but it does allow device-initiated slumber
b) It does not enable DevSlp mode

On my T440s test laptop I get the following power savings when idle:
medium_power		0.9W
med_power_with_dipm	1.2W
min_power		1.2W
Suggested-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

There is no agreed-upon definition of spin_unlock_wait()'s semantics,
and it appears that all callers could do just as well with a lock/unlock
pair.  This commit therefore eliminates the spin_unlock_wait() call and
associated else-clause and hoists the then-clause's lock and unlock out of
the "if" statement.  This should be safe from a performance perspective
because according to Tejun there should be few if any drivers that don't
set their own error handler.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: <linux-ide@vger.kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>

The kerneldoc comments for a couple of functions in drivers/ata/libata-eh.c
had fallen behind the current implementation, resulting in these doc build
warnings:

  ./drivers/ata/libata-eh.c:1449: warning: No description found for parameter 'link'
  ./drivers/ata/libata-eh.c:1449: warning: Excess function parameter 'ap' description in 'ata_eh_done'
  ./drivers/ata/libata-eh.c:1590: warning: No description found for parameter 'qc'
  ./drivers/ata/libata-eh.c:1590: warning: Excess function parameter 'dev' description in 'ata_eh_request_sense'

Update the comments and make the warnings go away.
Signed-off-by: NJonathan Corbet <corbet@lwn.net>
Signed-off-by: NTejun Heo <tj@kernel.org>

Remove unused variable ‘rc’.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

It is core functionality, and only one of the users is in the EH code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

The libata documentation is now using ReST. Update references
to it to point to the new place.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

The libata documentation is now using ReST. Update references
to it to point to the new place.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Fix typos and add the following to the scripts/spelling.txt:

  followings||following

While we are here, add a missing colon in the boilerplate in DT binding
documents.  The "you SoC" in allwinner,sunxi-pinctrl.txt was fixed as
well.

I reworded "as the followings:" to "as follows:" for
drivers/usb/gadget/udc/renesas_usb3.c.

Link: http://lkml.kernel.org/r/1481573103-11329-32-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Instead define the timeout behavior purely based on the host_template
eh_timed_out method and wire up the existing transport implementations
in the host templates.  This also clears up the confusion that the
transport template method overrides the host template one, so some
drivers have to re-override the transport template one.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NTyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Replace the sparse 256-pointer array for looking up protocol strings by
a switch() statement to reduce kernel size.

According to bloat-o-meter, this saves 910 bytes on m68k (32-bit), and
1892 bytes on arm64 (64-bit).
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

Add a new taskfile protocol ATA_PROT_NCQ_NODATA to handle
ATA NCQ NO-DATA commands correctly.
And fixup ata_scsi_zbc_out_xlat() to use it.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

Some taskfile protocol values where missing in ata_eh_link_report().
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

The taskfile protocol is a numeric value, and can not be ORed.  Currently
this is harmless as the protocol is always zeroed before, but if it ever
has a non-zero value the ORing would create incorrect results.
Signed-off-by: NHannes Reinecke <hare@suse.de>
[hch: updated patch description]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

sas_ata_strategy_handler() adds the works of the ata error handler to
system_unbound_wq. This workqueue asynchronously runs work items, so the
ata error handler will be performed concurrently on different CPUs. In
this case, ->host_failed will be decreased simultaneously in
scsi_eh_finish_cmd() on different CPUs, and become abnormal.

It will lead to permanently inequality between ->host_failed and
->host_busy, and scsi error handler thread won't start running. IO
errors after that won't be handled.

Since all scmds must have been handled in the strategy handler, just
remove the decrement in scsi_eh_finish_cmd() and zero ->host_busy after
the strategy handler to fix this race.

Fixes: 50824d6c ("[SCSI] libsas: async ata-eh")
Cc: stable@vger.kernel.org
Signed-off-by: NWei Fang <fangwei1@huawei.com>
Reviewed-by: NJames Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

ZAC drives implement a 'ZAC Management Out' command template,
which maps onto the ZBC OUT command.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

ZAC drives implement a 'ZAC Management In' command template,
which maps onto the ZBC IN command.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

Do not call ata_request_sense() if the sense code is already
present.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Implement MODE SELECT for the control mode page to allow the OS
to switch to descriptor sense.

tj: Dropped s/sb/cmd->sense_buffer/ in ata_gen_ata_sense().  Added
    @dev description to ata_msense_ctl_mode().
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

Whenever a sense code is set it would need to be evaluated to
update the error mask.

tj: Cosmetic formatting updates.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

If NCQ autosense or the sense data reporting feature is enabled
the LBA of the offending command should be stored in the sense
data 'information' field.

tj: s/(u64)-1/U64_MAX/
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

ACS-4 defines a sense data reporting feature set.
This patch implements support for it.

tj: Cosmetic formatting updates.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>

Some newer devices support NCQ autosense (cf ACS-4), so we should
be using it to retrieve the sense code and speed up recovery.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NTejun Heo <tj@kernel.org>