ata: libata-scsi: Cleanup ata_scsi_start_stop_xlat()

Now that libata does its own internal device power mode management
through libata EH, the scsi disk driver will not issue START STOP UNIT
commands anymore. We can receive this command only from user passthrough
operations. So there is no need to consider the system state and ATA
port flags for suspend to translate the command.

Since setting up the taskfile for the verify and standby
immediate commands is the same as done in ata_dev_power_set_active()
and ata_dev_power_set_standby(), factor out this code into the helper
function ata_dev_power_init_tf() to simplify ata_scsi_start_stop_xlat()
as well as ata_dev_power_set_active() and ata_dev_power_set_standby().

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

ata: libata-core: Do not register PM operations for SAS ports

libsas does its own domain based power management of ports. For such
ports, libata should not use a device type defining power management
operations as executing these operations for suspend/resume in addition
to libsas calls to ata_sas_port_suspend() and ata_sas_port_resume() is
not necessary (and likely dangerous to do, even though problems are not
seen currently).

Introduce the new ata_port_sas_type device_type for ports managed by
libsas. This new device type is used in ata_tport_add() and is defined
without power management operations.

Fixes: 2fcbdcb4c802 ("[SCSI] libata: export ata_port suspend/resume infrastructure for sas")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

ata: libata-scsi: Disable scsi device manage_system_start_stop

The introduction of a device link to create a consumer/supplier
relationship between the scsi device of an ATA device and the ATA port
of that ATA device fixes the ordering of system suspend and resume
operations. For suspend, the scsi device is suspended first and the ata
port after it. This is fine as this allows the synchronize cache and
START STOP UNIT commands issued by the scsi disk driver to be executed
before the ata port is disabled.

For resume operations, the ata port is resumed first, followed
by the scsi device. This allows having the request queue of the scsi
device to be unfrozen after the ata port resume is scheduled in EH,
thus avoiding to see new requests prematurely issued to the ATA device.
Since libata sets manage_system_start_stop to 1, the scsi disk resume
operation also results in issuing a START STOP UNIT command to the
device being resumed so that the device exits standby power mode.

However, restoring the ATA device to the active power mode must be
synchronized with libata EH processing of the port resume operation to
avoid either 1) seeing the start stop unit command being received too
early when the port is not yet resumed and ready to accept commands, or
after the port resume process issues commands such as IDENTIFY to
revalidate the device. In this last case, the risk is that the device
revalidation fails with timeout errors as the drive is still spun down.

Commit 0a8589055936 ("ata,scsi: do not issue START STOP UNIT on resume")
disabled issuing the START STOP UNIT command to avoid issues with it.
But this is incorrect as transitioning a device to the active power
mode from the standby power mode set on suspend requires a media access
command. The IDENTIFY, READ LOG and SET FEATURES commands executed in
libata EH context triggered by the ata port resume operation may thus
fail.

Fix these synchronization issues is by handling a device power mode
transitions for system suspend and resume directly in libata EH context,
without relying on the scsi disk driver management triggered with the
manage_system_start_stop flag.

To do this, the following libata helper functions are introduced:

1) ata_dev_power_set_standby():

This function issues a STANDBY IMMEDIATE command to transitiom a device
to the standby power mode. For HDDs, this spins down the disks. This
function applies only to ATA and ZAC devices and does nothing otherwise.
This function also does nothing for devices that have the
ATA_FLAG_NO_POWEROFF_SPINDOWN or ATA_FLAG_NO_HIBERNATE_SPINDOWN flag
set.

For suspend, call ata_dev_power_set_standby() in
ata_eh_handle_port_suspend() before the port is disabled and frozen.
ata_eh_unload() is also modified to transition all enabled devices to
the standby power mode when the system is shutdown or devices removed.

2) ata_dev_power_set_active() and

This function applies to ATA or ZAC devices and issues a VERIFY command
for 1 sector at LBA 0 to transition the device to the active power mode.
For HDDs, since this function will complete only once the disk spin up.
Its execution uses the same timeouts as for reset, to give the drive
enough time to complete spinup without triggering a command timeout.

For resume, call ata_dev_power_set_active() in
ata_eh_revalidate_and_attach() after the port has been enabled and
before any other command is issued to the device.

With these changes, the manage_system_start_stop and no_start_on_resume
scsi device flags do not need to be set in ata_scsi_dev_config(). The
flag manage_runtime_start_stop is still set to allow the sd driver to
spinup/spindown a disk through the sd runtime operations.

Fixes: 0a8589055936 ("ata,scsi: do not issue START STOP UNIT on resume")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

ata: libata-core: remove ata_bus_probe()

Remove ata_bus_probe() as it is unused.

Also, remove references to ata_bus_probe and port_disable in
Documentation/driver-api/libata.rst, as neither exist anymore.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

ata,scsi: cleanup __ata_port_probe()

Rename __ata_port_probe() to ata_port_probe() and drop the wrapper
ata_sas_async_probe().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

scsi: ata: libata: Set read/write commands CDL index

For devices supporting the command duration limits feature, translate the
dld field of read and write operation to set the command duration limit
index field of the command task file when the duration limit feature is
enabled.

The function ata_set_tf_cdl() is introduced to do this. For unqueued (non
NCQ) read and write operations, this function sets the command duration
limit index set as the lower 3 bits of the feature field. For queued NCQ
read/write commands, the index is set as the lower 3 bits of the auxiliary
field.

The flag ATA_QCFLAG_HAS_CDL is introduced to indicate that a command
taskfile has a non zero cdl field.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Igor Pylypiv <ipylypiv@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Co-developed-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Link: https://lore.kernel.org/r/20230511011356.227789-19-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ata: Declare SCSI host templates const

Make it explicit that ATA host templates are not modified.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> (for DWC AHCI SATA)
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com> (for Tegra)
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230322195515.1267197-5-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ata: libata: only set sense valid flag if sense data is valid

While this shouldn't be needed if all devices that claim that they
support NCQ autosense (ata_id_has_ncq_autosense()) and/or the sense
data reporting feature (ata_id_has_sense_reporting()), actually
supported those features.

However, there might be some old ATA devices that either have these
bits set, even when they don't support those features, or they simply
return malformed data when using those features.

These devices should be quirked, but in order to try to minimize the
impact for the users of these such devices, it was suggested by Damien
Le Moal that it might be a good idea to sanity check the sense data
received from the device. If the sense data looks bogus, then the
sense data is never added to the scsi_cmnd command.

Introduce a new function, ata_scsi_sense_is_valid(), and use it in all
places where sense data is received from the device.

Suggested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-core: Simplify ata_build_rw_tf()

Since ata_build_rw_tf() is only called from ata_scsi_rw_xlat() with the
tf, dev and tag arguments obtained from the queued command structure,
we can simplify the interface of ata_build_rw_tf() by passing directly
the qc structure as argument.

Furthermore, since ata_scsi_rw_xlat() is never used for internal
commands, we can also remove the internal tag check for the NCQ case.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-core: improve parameter names for ata_dev_set_feature()

ata_dev_set_feature() is currently used for enabling/disabling any ATA
feature, e.g. SETFEATURES_SPINUP and SETFEATURE_SENSE_DATA, i.e. it is
not only used to enable/disable SATA specific features.

For most features, the enable/disable bit is specified in the subcommand
specific field "count".
It is only for the specific subcommands "Enable SATA feature" (0x10) and
"Disable SATA feature" (0x90) where the field "count" is used to specify
a feature instead of enable/disable. The parameter names for this
function are thus quite misleading.

Rename the parameter names to be more generic and in line with ACS-5,
and remove the references to "SATA FEATURES" in the kernel-doc.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-eh: fix sloppy result type of ata_internal_cmd_timeout()

ata_internal_cmd_timeout() returns *unsigned long* timeout in ms, however
ata_exec_internal_sg() passes that timeout to msecs_to_jiffies() that takes
just *unsigned int*. Change ata_internal_cmd_timeout()'s result type to
*unsigned int* as well, also updating the *struct* ata_eh_cmd_timeout_ent
and the command timeout tables -- all timeouts fit into *unsigned int* but
we have to change ULONG_MAX to UINT_MAX...

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-core: fix sloppy parameter type in ata_exec_internal[_sg]()

Make the 'timeout' parameter to ata_exec_internal_sg() *unsigned int* as
msecs_to_jiffies() that it calls takes just *unsigned int* for the time in
milliseconds. Then follow the suit with ata_exec_internal(), its only
caller; also fix up ata_dev_set_feature(), the only ata_exec_internal()'s
caller that explicitly passes *unsigned long* variable for timeout...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-core: make ata_exec_internal_sg() *static*

ata_exec_internal_sg() is only called by ata_exec_internal() further in
the same file, so we can make it *static* and remove its prototype from
drivers/ata/libata.h...

Suggested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

libata: Improve ATA queued command allocation

Improve ATA queued command allocation as follows:

- For attaining a qc tag for a SAS host we need to allocate a bit in
ata_port.sas_tag_allocated bitmap.

However we already have a unique tag per device in range
[0, ATA_MAX_QUEUE -1] in the scsi cmnd budget token, so just use that
instead.

- It is a bit pointless to have ata_qc_new_init() in libata-core.c since it
pokes scsi internals, so inline it in ata_scsi_qc_new() (in
libata-scsi.c). Also update Doc accordingly.

- Use standard SCSI helpers set_host_byte() and set_status_byte() in
ata_scsi_qc_new().

Christoph Hellwig originally contributed the change to inline
ata_qc_new_init().

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata-acpi: kill ata_acpi_on_suspend()

Since the commit c05e6ff035c1b25d17364a685432 ("libata-acpi: implement
and use ata_acpi_init_gtm()") ata_acpi_on_suspend() just returns 0, so
its call from ata_eh_handle_port_suspend() doesn't make sense anymore.
Remove the function completely, at last...

Found by Linux Verification Center (linuxtesting.org) with the SVACE
static analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata: remove pointless VPRINTK() calls

Most of the information is already covered by tracepoints
(if not downright pointless), so remove the VPRINTK() calls.
And while we're at it, remove ata_scsi_dump_cdb(), too,
as this information can be retrieved from scsi tracing.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata: revamp ata_get_cmd_descript()

Rename ata_get_cmd_descrip() to ata_get_cmd_name() and simplify
it to return "unknown" instead of NULL.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: libata: whitespace cleanup

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

ata: make "libata.force" kernel parameter optional

Add ATA_FORCE config option (visible only if EXPERT config
option is enabled) and make "libata.force" kernel parameter
optional.

Code size savings on m68k arch using (modified) atari_defconfig:

text data bss dec hex filename
w/ CONFIG_ATA_FORCE=y:
31983 572 40 32595 7f53 drivers/ata/libata-core.o
w/ CONFIG_ATA_FROCE=n:
28958 316 32 29306 727a drivers/ata/libata-core.o

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ata: move ata_sas_*() to libata-sata.c

* un-inline:
- ata_scsi_dump_cdb()
- __ata_scsi_queuecmd()

* un-static:
- ata_scsi_sdev_config()
- ata_scsi_dev_config()
- ata_scsi_dump_cdb()
- __ata_scsi_queuecmd()

* move ata_sas_*() to libata-sata.c:

* add static inlines for CONFIG_SATA_HOST=n case for
ata_sas_{allocate,free}_tag()

Code size savings on m68k arch using (modified) atari_defconfig:

text data bss dec hex filename
before:
19137 23 576 19736 4d18 drivers/ata/libata-scsi.o
after:
18330 23 576 18929 49f1 drivers/ata/libata-scsi.o

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ata: start separating SATA specific code from libata-scsi.c

Start separating SATA specific code from libata-scsi.c:

* un-static ata_scsi_find_dev()

* move following code to libata-sata.c:
- SATA only sysfs device attributes handling
- __ata_change_queue_depth()
- ata_scsi_change_queue_depth()

* cover with CONFIG_SATA_HOST ifdef SATA only sysfs device
attributes handling code and ATA_SHT_NCQ() macro in
<linux/libata.h>

Code size savings on m68k arch using (modified) atari_defconfig:

text data bss dec hex filename
before:
20702 105 576 21383 5387 drivers/ata/libata-scsi.o
after:
19137 23 576 19736 4d18 drivers/ata/libata-scsi.o

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ata: move sata_link_hardreset() to libata-sata.c

* move sata_link_hardreset() to libata-sata.c

* add static inline for CONFIG_SATA_HOST=n case

* make sata_set_spd_needed() static

Code size savings on m68k arch using (modified) atari_defconfig:

text data bss dec hex filename
before:
32724 572 40 33336 8238 drivers/ata/libata-core.o
after:
32559 572 40 33171 8193 drivers/ata/libata-core.o

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ata: move *sata_set_spd*() to libata-sata.c

* move *sata_set_spd*() to libata-sata.c

* add static inlines for CONFIG_SATA_HOST=n case

Code size savings on m68k arch using (modified) atari_defconfig:

text data bss dec hex filename
before:
32842 572 40 33458 82ae drivers/ata/libata-core.o
after:
32812 572 40 33428 8290 drivers/ata/libata-core.o

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18

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: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154042.342335923@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: libsas: dynamically allocate and free ata host

Commit 2623c7a5f2 ("libata: add refcounting to ata_host") v4.17+ introduced
refcounting to ata_host and will increase or decrease the refcount when
adding or deleting transport ATA port.

Now the ata host for libsas is embedded in domain_device, and the ->kref
member is not initialized. Afer we add ata transport class, ata_host_get()
will be called when adding transport ATA port and a warning will be
triggered as below:

refcount_t: increment on 0; use-after-free.
WARNING: CPU: 2 PID: 103 at
lib/refcount.c:153 refcount_inc+0x40/0x48 ...... Call trace:
refcount_inc+0x40/0x48
ata_host_get+0x10/0x18
ata_tport_add+0x40/0x120
ata_sas_tport_add+0xc/0x14
sas_ata_init+0x7c/0xc8
sas_discover_domain+0x380/0x53c
process_one_work+0x12c/0x288
worker_thread+0x58/0x3f0
kthread+0xfc/0x128
ret_from_fork+0x10/0x18

And also when removing transport ATA port ata_host_put() will be called and
another similar warning will be triggered. If the refcount decreased to
zero, the ata host will be freed. But this ata host is only part of
domain_device, it cannot be freed directly.

So we have to change this embedded static ata host to a dynamically
allocated ata host and initialize the ->kref member. To use ata_host_get()
and ata_host_put() in libsas, we need to move the declaration of these
functions to the public libata.h and export them.

Fixes: b6240a4df018 ("scsi: libsas: add transport class for ATA devices")
Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: Taras Kondratiuk <takondra@cisco.com>
CC: Tejun Heo <tj@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

libata: add refcounting to ata_host

After commit 9a6d6a2ddabb ("ata: make ata port as parent device of scsi
host") manual driver unbind/remove causes use-after-free.

Unbind unconditionally invokes devres_release_all() which calls
ata_host_release() and frees ata_host/ata_port memory while it is still
being referenced as a parent of SCSI host. When SCSI host is finally
released scsi_host_dev_release() calls put_device(parent) and accesses
freed ata_port memory.

Add reference counting to make sure that ata_host lives long enough.

Bug report: https://lkml.org/lkml/2017/11/1/945
Fixes: 9a6d6a2ddabb ("ata: make ata port as parent device of scsi host")
Cc: Tejun Heo <tj@kernel.org>
Cc: Lin Ming <minggr@gmail.com>
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Taras Kondratiuk <takondra@cisco.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: Convert timers to use timer_setup()

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: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: linux-ide@vger.kernel.org
Link: https://lkml.kernel.org/r/20171005004842.GA23011@beast

libata: make ata_port_type const

Make this const as it is only stored in the const field of a device
structure. Make the declaration in header const too.

Structure found using Coccinelle and changes done by hand.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: move ata_read_log_page to libata-core.c

It is core functionality, and only one of the users is in the EH code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

ata: update references for libata documentation

The libata documentation is now using ReST. Update references
to it to point to the new place.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

ata: update references for libata documentation

The libata documentation is now using ReST. Update references
to it to point to the new place.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

scsi: remove eh_timed_out methods in the transport template

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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

libata: move struct ata_scsi_args to libata-scsi.c

It's only used in libata-scsi.c, so move it closer to the users.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: Make ata_sg_clean() static again

Commit 70e6ad0c6d1e6cb9 ("[PATCH] libata: prepare ata_sg_clean() for
invocation from EH") made ata_sg_clean() global, but no user outside
libata-core.c has ever materialized.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

ata: Enabling ATA Command Priorities

This patch checks to see if an ATA device supports NCQ command priorities.
If so and the user has specified an iocontext that indicates
IO_PRIO_CLASS_RT then we build a tf with a high priority command.

This is done to improve the tail latency of commands that are high
priority by passing priority to the device.

tj: Removed trivial ata_ncq_prio_enabled() and open-coded the test.

Signed-off-by: Adam Manzanares <adam.manzanares@hgst.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: Implement control mode page to select sense format

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: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata-eh: Set 'information' field for autosense

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: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: sanitize ata_tf_read_block()

Return U64_MAX if ata_tf_read_block() could not decode the LBA
address, and do not set the information sense descriptor in
ata_gen_ata_sense() in these cases.

tj: s/(u64)-1/U64_MAX/

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: Implement NCQ autosense

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: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

Revert "libata: Implement NCQ autosense"

This reverts commit 42b966fbf35da9c87f08d98f9b8978edf9e717cf.

As implemented, ACS-4 sense reporting for ATA devices bypasses error
diagnosis and handling in libata degrading EH behavior significantly.
Revert the related changes for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org #v4.1+

Revert "libata-eh: Set 'information' field for autosense"

This reverts commit a1524f226a02aa6edebd90ae0752e97cfd78b159.

As implemented, ACS-4 sense reporting for ATA devices bypasses error
diagnosis and handling in libata degrading EH behavior significantly.
Revert the related changes for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org #v4.1+

libata-eh: Set 'information' field for autosense

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.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: Implement NCQ autosense

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: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: move sas ata tag allocation to libata-scsi.c

Basically move the sas ata tag allocation to libata-scsi.c to make it clear
these staffs are just for sas.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

libata: use blk taging

libata uses its own tag management which is duplication and the
implementation is poor. And if we switch to blk-mq, tag is build-in.
It's time to switch to generic taging.

The SAS driver has its own tag management, and looks we can't directly
map the host controler tag to SATA tag. So I just bypassed the SAS case.

I changed the code/variable name for the tag management of libata to
make it self contained. Only sas will use it. Later if libsas implements
its tag management, the tag management code in libata can be deleted
easily.

Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>

ata: libata-core: Remove unused function

Remove the function ata_do_simple_cmd() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Tejun Heo <tj@kernel.org>

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>

ATA / ACPI: remove power dependent device handling

Previously, we wanted SCSI devices corrsponding to ATA devices to
be runtime resumed when the power resource for those ATA device was
turned on by some other device, so we added the SCSI device to the
dependent device list of the ATA device's ACPI node. However, this
code has no effect after commit 41863fc (ACPI / power: Drop automaitc
resume of power resource dependent devices) and the mechanism it was
supposed to implement is regarded as a bad idea now, so drop it.

[rjw: Changelog]
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

libata: acpi: Remove ata_dev_acpi_handle stub in libata.h

The ata_dev_acpi_handle is defined in libata-acpi.c and the only
external user is libata-zpodd.c, which is built when CONFIG_ATA_ACPI
is set, so there is no need to make an empty stub function for
ONFIG_ATA_ACPI case in libata.h. It also causes compile errors due to
acpi_handle is not defined when !CONFIG_ACPI. This patch fixes this
problem by removing the empty stub.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

ata: acpi: rework the ata acpi bind support

Binding ACPI handle to SCSI device has several drawbacks, namely:
1 During ATA device initialization time, ACPI handle will be needed
while SCSI devices are not created yet. So each time ACPI handle is
needed, instead of retrieving the handle by ACPI_HANDLE macro,
a namespace scan is performed to find the handle for the corresponding
ATA device. This is inefficient, and also expose a restriction on
calling path not holding any lock.
2 The binding to SCSI device tree makes code complex, while at the same
time doesn't bring us any benefit. All ACPI handlings are still done
in ATA module, not in SCSI.

Rework the ATA ACPI binding code to bind ACPI handle to ATA transport
devices(ATA port and ATA device). The binding needs to be done only once,
since the ATA transport devices do not go away with hotplug. And due to
this, the flush_work call in hotplug handler for ATA bay is no longer
needed.

Tested on an Intel test platform for binding and runtime power off for
ODD(ZPODD) and hard disk; on an ASUS S400C for binding and normal boot
and S3, where its SATA port node has _SDD and _GTF control methods when
configured as an AHCI controller and its PATA device node has _GTF
control method when configured as an IDE controller. SATA PMP binding
and ATA hotplug is not tested.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Dirk Griesbach <spamthis@freenet.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata: acpi: remove dead code for ata_acpi_(un)bind

Commit 7381fe737 "libata-acpi: remove redundent code for power resource
handling" removed ata_acpi_(un)bind but left their prototypes in libata.h,
so remove them.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libata-acpi: add back ACPI based hotplug functionality

Commit 30dcf76acc69 "libata: migrate ACPI code over to new bindings"
mistakenly dropped the code to register hotplug notificaion handler
for ATA port/devices, causing regression for people using ATA bay,
as kernel bug #59871 shows.

Fix this by adding back the hotplug notification handler registration
code. Since this code has to be run once and notification needs to
be installed on every ATA port/devices handle no matter if there is
actual device attached, we can't do this in binding time for ATA
device ACPI handle, as the binding only occurs when a SCSI device is
created, i.e. there is device attached. So introduce the
ata_acpi_hotplug_init() function to loop scan all ATA ACPI handles
and if it is available, install the notificaion handler for it during
ATA init time.

With the ATA ACPI handle binding to SCSI device tree, it is possible
now that when the SCSI hotplug work removes the SCSI device, the ACPI
unbind function will find that the corresponding ACPI device has
already been deleted by dock driver, causing a scaring message like:
[ 128.263966] scsi 4:0:0:0: Oops, 'acpi_handle' corrupt
Fix this by waiting for SCSI hotplug task finish in our notificaion
handler, so that the removal of ACPI device done in ACPI unbind
function triggered by the removal of SCSI device is run earlier when
ACPI device is still available.

[rjw: Rebased]
References: https://bugzilla.kernel.org/show_bug.cgi?id=59871
Reported-bisected-and-tested-by: Dirk Griesbach <spamthis@freenet.de>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: 3.6+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

libata: handle power transition of ODD

When ata port is runtime suspended, it will check if the ODD attched to
it is a zero power(ZP) capable ODD and if the ZP capable ODD is in zero
power ready state. And if this is not the case, the highest acpi state
will be limited to ACPI_STATE_D3_HOT to avoid powering off the ODD. And
if the ODD can be powered off, runtime wake capability needs to be
enabled and powered_off flag will be set to let resume code knows that
the ODD was in powered off state.

And on resume, before it is powered on, if it was powered off during
suspend, runtime wake capability needs to be disabled. After it is
recovered, the ODD is considered functional, post power on processing
like eject tray if the ODD is drawer type is done, and several ZPODD
related fields will also be reset.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: check zero power ready status for ZPODD

Per the Mount Fuji spec, the ODD is considered zero power ready when:
- For slot type ODD, no media inside;
- For tray type ODD, no media inside and tray closed.

The information can be retrieved by either the returned information of
command GET_EVENT_STATUS_NOTIFICATION(the command is used to poll for
media event) or sense code.

The information provided by the media status byte is not accurate, it
is possible that after a new disc is just inserted, the status byte
still returns media not present. So this information can not be used as
the deciding factor, we use sense code to decide if zpready status is
true.

When we first sensed the ODD in the zero power ready state, the
zp_sampled will be set and timestamp will be recoreded. And after ODD
stayed in this state for some pre-defined period, the ODD is considered
as power off ready and the zp_ready flag will be set. The zp_ready flag
serves as the deciding factor other code will use to see if power off is
OK for the ODD.

The Mount Fuji spec suggests a delay should be used here, to avoid the
case user ejects the ODD and then instantly inserts a new one again, so
that we can avoid a power transition. And some ODDs may be slow to place
its head to the home position after disc is ejected, so a delay here is
generally a good idea. And the delay time can be changed via the module
param zpodd_poweroff_delay.

The zero power ready status check is performed in the ata port's runtime
suspend code path, when port is not frozen yet, as we need to issue some
IOs to the ODD.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: identify and init ZPODD devices

The ODD can be enabled for ZPODD if the following three conditions are
satisfied:
1 The ODD supports device attention;
2 The platform can runtime power off the ODD through ACPI;
3 The ODD is either slot type or drawer type.
For such ODDs, zpodd_init is called and a new structure is allocated for
it to store ZPODD related stuffs.

And the zpodd_dev_enabled function is used to test if ZPODD is currently
enabled for this ODD.

A new config CONFIG_SATA_ZPODD is added to selectively build ZPODD code.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

ahci: implement aggressive SATA device sleep support

Device Sleep is a feature as described in AHCI 1.3.1 Technical Proposal.
This feature enables an HBA and SATA storage device to enter the DevSleep
interface state, enabling lower power SATA-based systems.

Aggressive Device Sleep enables the HBA to assert the DEVSLP signal as
soon as there are no commands outstanding to the device and the port
specific Device Sleep idle timer has expired. This enables autonomous
entry into the DevSleep interface state without waiting for software
in power sensitive systems.

This patch enables Aggressive Device Sleep only if both host controller
and device support it.

Tested on AMD reference board together with Device Sleep supported device
sample.

Signed-off-by: Shane Huang <shane.huang@amd.com>
Reviewed-by: Aaron Lu <aaron.lwe@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-acpi: add missing inlines in libata.h

Adds inline for ata_acpi_unregister/ata_acpi_bind/ata_acpi_unbind
in drivers/ata/libata.h for !CONFIG_ATA_ACPI to fix below warnings.

warning: 'ata_acpi_unregister' defined but not used [-Wunused-function]
warning: 'ata_acpi_bind' defined but not used [-Wunused-function]
warning: 'ata_acpi_unbind' defined but not used [-Wunused-function]

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-acpi: add ata port runtime D3Cold support

ATA port may support runtime D3Cold state, for example, Zero-power ODD case.
This patch adds wakeup notifier and enable/disable run_wake during
supend/resume.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: migrate ACPI code over to new bindings

Now that we have the ability to directly glue the ACPI namespace to the
driver model in libata, we don't need the custom code to handle the same
thing. Remove it and migrate the functions over to the new code.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Holger Macht <holger@homac.de>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: bind the Linux device tree to the ACPI device tree

Associate the ACPI device tree and libata devices.
This patch uses the generic ACPI glue framework to do so.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Holger Macht <holger@homac.de>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: make ata_print_id atomic

This variable is incremented from multiple contexts (module_init via
libata-lldds and the libsas discovery thread). Make it atomic to head
off any chance of libsas and libata creating duplicate ids.

Acked-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[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>

[SCSI] libsas: execute transport link resets with libata-eh via host workqueue

Link resets leave ata affiliations intact, so arrange for libsas to make
an effort to avoid dropping the device due to a slow-to-recover link.
Towards this end carry out reset in the host workqueue so that it can
check for ata devices and kick the reset request to libata. Hard
resets, in contrast, bypass libata since they are meant for associating
an ata device with another initiator in the domain (tears down
affiliations).

Need to add a new transport_sas_phy_reset() since the current
sas_phy_reset() is a utility function to libsas lldds. They are not
prepared for it to loop back into eh.

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

ata: add ata port system PM callbacks

Change ata_host_request_pm to ata_port_request_pm which performs
port suspend/resume.

Add ata port type driver which implements port PM callbacks.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: plumb sas port scan into standard libata paths

The function ata_sas_port_init() has always really done its own thing.
However, as a precursor to moving to the libata new eh, it has to be
properly using the standard libata scan paths. This means separating
the current libata scan paths into pieces which can be shared with
libsas and pieces which cant (really just the async call and the host
scan).

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[SCSI] libata: plumb sas port scan into standard libata paths

The function ata_sas_port_init() has always really done its own thing.
However, as a precursor to moving to the libata new eh, it has to be
properly using the standard libata scan paths. This means separating
the current libata scan paths into pieces which can be shared with
libsas and pieces which cant (really just the async call and the host
scan).

Cc: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

libata: implement cross-port EH exclusion

In libata, the non-EH code paths should always take and release
ap->lock explicitly when accessing hardware or shared data structures.
However, once EH is active, it's assumed that the port is owned by EH
and EH methods don't explicitly take ap->lock unless race from irq
handler or other code paths are expected. However, libata EH didn't
guarantee exclusion among EHs for ports of the same host. IOW,
multiple EHs may execute in parallel on multiple ports of the same
controller.

In many cases, especially in SATA, the ports are completely
independent of each other and this doesn't cause problems; however,
there are cases where different ports share the same resource, which
lead to obscure timing related bugs such as the one fixed by commit
213373cf (ata_piix: fix locking around SIDPR access).

This patch implements exclusion among EHs of the same host. When EH
begins, it acquires per-host EH ownership by calling ata_eh_acquire().
When EH finishes, the ownership is released by calling
ata_eh_release(). EH ownership is also released whenever the EH
thread goes to sleep from ata_msleep() or explicitly and reacquired
after waking up.

This ensures that while EH is actively accessing the hardware, it has
exclusive access to it while allowing EHs to interleave and progress
in parallel as they hit waiting stages, which dominate the time spent
in EH. This achieves cross-port EH exclusion without pervasive and
fragile changes while still allowing parallel EH for the most part.

This was first reported by yuanding02@gmail.com more than three years
ago in the following bugzilla. :-)

https://bugzilla.kernel.org/show_bug.cgi?id=8223

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Reported-by: yuanding02@gmail.com
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: implement LPM support for port multipliers

Port multipliers can do DIPM on fan-out links fine. Implement support
for it. Tested w/ SIMG 57xx and marvell PMPs. Both the host and
fan-out links enter power save modes nicely.

SIMG 37xx and 47xx report link offline on SStatus causing EH to detach
the devices. Blacklisted.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: reimplement link power management

The current LPM implementation has the following issues.

* Operation order isn't well thought-out. e.g. HIPM should be
configured after IPM in SControl is properly configured. Not the
other way around.

* Suspend/resume paths call ata_lpm_enable/disable() which must only
be called from EH context directly. Also, ata_lpm_enable/disable()
were called whether LPM was in use or not.

* Implementation is per-port when it should be per-link. As a result,
it can't be used for controllers with slave links or PMP.

* LPM state isn't managed consistently. After a link reset for
whatever reason including suspend/resume the actual LPM state would
be reset leaving ap->lpm_policy inconsistent.

* Generic/driver-specific logic boundary isn't clear. Currently,
libahci has to mangle stuff which libata EH proper should be
handling. This makes the implementation unnecessarily complex and
fragile.

* Tied to ALPM. Doesn't consider DIPM only cases and doesn't check
whether the device allows HIPM.

* Error handling isn't implemented.

Given the extent of mismatch with the rest of libata, I don't think
trying to fix it piecewise makes much sense. This patch reimplements
LPM support.

* The new implementation is per-link. The target policy is still
port-wide (ap->target_lpm_policy) but all the mechanisms and states
are per-link and integrate well with the rest of link abstraction
and can work with slave and PMP links.

* Core EH has proper control of LPM state. LPM state is reconfigured
when and only when reconfiguration is necessary. It makes sure that
LPM state is reset when probing for new device on the link.
Controller agnostic logic is now implemented in libata EH proper and
driver implementation only has to deal with controller specifics.

* Proper error handling. LPM config failure is attributed to the
device on the link and LPM is disabled for the link if it fails
repeatedly.

* ops->enable/disable_pm() are replaced with single ops->set_lpm()
which takes @policy and @hints. This simplifies driver specific
implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: implement sata_link_scr_lpm() and make ata_dev_set_feature() global

Link power management is about to be reimplemented. Prepare for it.

* Implement sata_link_scr_lpm().

* Drop static from ata_dev_set_feature() and make it available to
other libata files.

* Trivial whitespace adjustments.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: clean up lpm related symbols and sysfs show/store functions

Link power management related symbols are in confusing state w/ mixed
usages of lpm, ipm and pm. This patch cleans up lpm related symbols
and sysfs show/store functions as follows.

* lpm states - NOT_AVAILABLE, MIN_POWER, MAX_PERFORMANCE and
MEDIUM_POWER are renamed to ATA_LPM_UNKNOWN and
ATA_LPM_{MIN|MAX|MED}_POWER.

* Pre/postfixes are unified to lpm.

* sysfs show/store functions for link_power_management_policy were
curiously named get/put and unnecessarily complex. Renamed to
show/store and simplified.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[libata] Add ATA transport class

This is a scheleton for libata transport class.
All information is read only, exporting information from libata:
- ata_port class: one per ATA port
- ata_link class: one per ATA port or 15 for SATA Port Multiplier
- ata_device class: up to 2 for PATA link, usually one for SATA.

Signed-off-by: Gwendal Grignou <gwendal@google.com>
Reviewed-by: Grant Grundler <grundler@google.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: take advantage of cmwq and remove concurrency limitations

libata has two concurrency related limitations.

a. ata_wq which is used for polling PIO has single thread per CPU. If
there are multiple devices doing polling PIO on the same CPU, they
can't be executed simultaneously.

b. ata_aux_wq which is used for SCSI probing has single thread. In
cases where SCSI probing is stalled for extended period of time
which is possible for ATAPI devices, this will stall all probing.

#a is solved by increasing maximum concurrency of ata_wq. Please note
that polling PIO might be used under allocation path and thus needs to
be served by a separate wq with a rescuer.

#b is solved by using the default wq instead and achieving exclusion
via per-port mutex.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>

libata-sff: separate out BMDMA EH

Some of error handling logic in ata_sff_error_handler() and all of
ata_sff_post_internal_cmd() are for BMDMA. Create
ata_bmdma_error_handler() and ata_bmdma_post_internal_cmd() and move
BMDMA part into those.

While at it, change DMA protocol check to ata_is_dma(), fix
post_internal_cmd to call ap->ops->bmdma_stop instead of directly
calling ata_bmdma_stop() and open code hardreset selection so that
ata_std_error_handler() doesn't have to know about sff hardreset.

As these two functions are BMDMA specific, there's no reason to check
for bmdma_addr before calling bmdma methods if the protocol of the
failed command is DMA. sata_mv and pata_mpc52xx now don't need to set
.post_internal_cmd to ATA_OP_NULL and pata_icside and sata_qstor don't
need to set it to their bmdma_stop routines.

ata_sff_post_internal_cmd() becomes noop and is removed.

This fixes p3 described in clean-up-BMDMA-initialization patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-sff: port_task is SFF specific

port_task is tightly bound to the standard SFF PIO HSM implementation.
Using it for any other purpose would be error-prone and there's no
such user and if some drivers need such feature, it would be much
better off using its own. Move it inside CONFIG_ATA_SFF and rename it
to sff_pio_task.

The only function which is exposed to the core layer is
ata_sff_flush_pio_task() which is renamed from ata_port_flush_task()
and now also takes care of resetting hsm_task_state to HSM_ST_IDLE,
which is possible as it's now specific to PIO HSM.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-sff: introduce ata_sff_init/exit() and ata_sff_port_init()

In preparation of proper SFF/BMDMA separation, introduce
ata_sff_init/exit() and ata_sff_port_init(). These functions
currently don't do anything.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-sff: kill unused prototype and make ata_dev_select() static

ata_irq_on() was renamed to ata_sff_irq_on() and exported a while ago
but prototype for the original function lingered in
drivers/ata/libata.h. Kill it. Also, ata_dev_select() is only used
inside drivers/ata/libata-sff.c. Make it static.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: make gtf_filter per-dev

Add ->gtf_filter to ata_device and set it to ata_acpi_gtf_filter when
initializing ata_link. This is to allow quirks which apply different
gtf filters.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: add command name parsing for error output

This patch improve libata's output for error/notification messages
to allow easier comprehension and debugging:

When ATAPI commands issued through the SCSI layer fail, use SCSI
functions to print the CDB in human-readable form instead of just
dumping out the CDB in hex.

Print out the name of the failed command (as defined by the ATA
specification) in error handling output along with the raw register
contents.

When reporting status of ACPI taskfile commands executed on resume,
also output the names of the commands being executed (or not) in
readable form.

Since the extra data for printing command names increases kernel
size slightly, a config option has been added to allow disabling
command name output (as well as some of the error register parsing)
for those highly sensitive to kernel text size.

Signed-off-by: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[libata] Export ata_pio_queue_task() so that it can be used from sata_mv.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: add @spd_limit to sata_down_spd_limit()

Add @spd_limit to sata_down_spd_limit() so that the caller can specify
the SPD limit it wants. This parameter doesn't get in the way even
when it's too low. The closest possible limit is applied.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: move ata_dev_disable() to libata-eh.c

ata_dev_disable() is about to be more tightly integrated into EH
logic. Move it to libata-eh.c.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: revert convert-to-block-tagging patches

This patch reverts the following three commits which convert libata to
use block layer tagging.

43a49cbdf31e812c0d8f553d433b09b421f5d52c
e013e13bf605b9e6b702adffbe2853cfc60e7806
2fca5ccf97d2c28bcfce44f5b07d85e74e3cd18e

Although using block layer tagging is the right direction, due to the
tight coupling among tag number, data structure allocation and
hardware command slot allocation, libata doesn't work correctly with
the current conversion.

The biggest problem is guaranteeing that tag 0 is always used for
non-NCQ commands. Due to the way blk-tag is implemented and how SCSI
starts and finishes requests, such guarantee can't be made. I'm not
sure whether this would actually break any low level driver but it
doesn't look like a good idea to break such assumption given the
frailty of ATA controllers.

So, for the time being, keep using the old dumb in-libata qc
allocation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axobe <jens.axboe@oracle.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

libata: switch to using block layer tagging support

libata currently has a pretty dumb ATA_MAX_QUEUE loop for finding
a free tag to use. Instead of fixing that up, convert libata to
using block layer tagging - gets rid of code in libata, and is also
much faster.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

libata: implement slave_link

Explanation taken from the comment of ata_slave_link_init().

In libata, a port contains links and a link contains devices. There
is single host link but if a PMP is attached to it, there can be
multiple fan-out links. On SATA, there's usually a single device
connected to a link but PATA and SATA controllers emulating TF based
interface can have two - master and slave.

However, there are a few controllers which don't fit into this
abstraction too well - SATA controllers which emulate TF interface
with both master and slave devices but also have separate SCR
register sets for each device. These controllers need separate links
for physical link handling (e.g. onlineness, link speed) but should
be treated like a traditional M/S controller for everything else
(e.g. command issue, softreset).

slave_link is libata's way of handling this class of controllers
without impacting core layer too much. For anything other than
physical link handling, the default host link is used for both master
and slave. For physical link handling, separate @ap->slave_link is
used. All dirty details are implemented inside libata core layer.
From LLD's POV, the only difference is that prereset, hardreset and
postreset are called once more for the slave link, so the reset
sequence looks like the following.

prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
softreset(M) -> postreset(M) -> postreset(S)

Note that softreset is called only for the master. Softreset resets
both M/S by definition, so SRST on master should handle both (the
standard method will work just fine).

As slave_link excludes PMP support and only code paths which deal with
the attributes of physical link are affected, all the changes are
localized to libata.h, libata-core.c and libata-eh.c.

* ata_is_host_link() updated so that slave_link is considered as host
link too.

* iterator extended to iterate over the slave_link when using the
underbarred version.

* force param handling updated such that devno 16 is mapped to the
slave link/device.

* ata_link_on/offline() updated to return the combined result from
master and slave link. ata_phys_link_on/offline() are the direct
versions.

* EH autopsy and report are performed separately for master slave
links. Reset is udpated to implement the above described reset
sequence.

Except for reset update, most changes are minor, many of them just
modifying dev->link to ata_dev_phys_link(dev) or using phys online
test instead.

After this update, LLDs can take full advantage of per-dev SCR
registers by simply turning on slave link.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: update atapi disable handling

Global and per-LLD ATAPI disable checks were done in the command issue
path probably because it was left out during EH conversion. On
affected machines, this can cause lots of warning messages. Move them
to where they belong - the probing path.

Reported by Chunbo Luo.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chunbo Luo <chunbo.luo@windriver.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: improve EH internal command timeout handling

ATA_TMOUT_INTERNAL which was 30secs were used for all internal
commands which is way too long when something goes wrong. This patch
implements command type based stepped timeouts. Different command
types can use different timeouts and each command type can use
different timeout values after timeouts.

ie. the initial timeout is set to a value which should cover most of
the cases but not too long so that run away cases don't delay things
too much. After the first try times out, the second try can use
longer timeout and if that one times out too, it can go for full 30sec
timeout.

IDENTIFYs use 5s - 10s - 30s timeout and all other commands use 5s -
10s timeouts.

This patch significantly cuts down the needed time to handle failure
cases while still allowing libata to work with nut job devices through
retries.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: don't check whether to use DMA or not for no data commands

There's no reason to check whether to use DMA or not for no data
commands. Don't do it. While at it, make local variable using_pio in
atapi_xlat() set iff ATAPI_PROT_PIO is going to be used and rename
ata_check_atapi_dma() to atapi_check_dma() for consistency.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata-scsi: clean up inquiry / mode sense related functions

* make ata_scsiop_*() static
* make ata_scsi_set_sense() static and move it above its users
* make ata_scsi_rbuf_fill() static
* kill unused ata_scsi_badcmd()

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

make sata_set_spd_needed() static

sata_set_spd_needed() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: make PMP support optional

Make PMP support optional by adding CONFIG_SATA_PMP and leaving out
libata-pmp.c if it isn't set. PMP helpers return constant values if
PMP support is not enabled and PMP declarations alias non-PMP
counterparts. This makes the compiler to leave out PMP related part
out and LLDs to use non-PMP counterparts automatically.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: separate PMP support code from core code

Most of PMP support code is already in libata-pmp.c. All that are in
libata-core.c are sata_pmp_port_ops and EXPORTs. Move them to
libata-pmp.c. Also, collect PMP related prototypes and declarations
in header files and move them right above of SFF stuff.

This change is to make PMP support optional.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: make SFF support optional

Now that SFF support is completely separated out from the core layer,
it can be made optional. Add CONFIG_ATA_SFF and let SFF drivers
depend on it. If CONFIG_ATA_SFF isn't set, all codes in libata-sff.c
and data structures for SFF support are disabled. This saves good
number of bytes for small systems.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: implement and use sata_std_hardreset()

Implement sata_std_hardreset(), which simply wraps around
sata_link_hardreset(). sata_std_hardreset() becomes new standard
hardreset method for sata_port_ops and sata_sff_hardreset() moves from
ata_base_port_ops to ata_sff_port_ops, which is where it really
belongs.

ata_is_builtin_hardreset() is added so that both
ata_std_error_handler() and ata_sff_error_handler() skip both builtin
hardresets if SCR isn't accessible.

piix_sidpr_hardreset() in ata_piix.c is identical to
sata_std_hardreset() in functionality and got replaced with the
standard function.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: separate out ata_wait_ready() and implement ata_wait_after_reset()

Factor out waiting logic (which is common to all ATA controllers) from
ata_sff_wait_ready() into ata_wait_ready(). ata_wait_ready() takes
@check_ready function pointer and uses it to poll for readiness. This
allows non-SFF controllers to use ata_wait_ready() to wait for link
readiness.

This patch also implements ata_wait_after_reset() - generic version of
ata_sff_wait_after_reset() - using ata_wait_ready().

ata_sff_wait_ready() is reimplemented using ata_wait_ready() and
ata_sff_check_ready(). Functionality remains the same.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: kill unused ata_flush_cache()

ata_flush_code() hasn't been in use for quite some time now. Kill it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: make ata_tf_to_lba[48]() generic

ata_tf_to_lba[48]() currently return LBA in tf + 1 for
ata_read_native_max_address(). Make them return LBA and make it
global so that it can be used to read LBA off TF for other purposes.
ata_read_native_max_address() now adds 1 itself.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: reorganize SFF related stuff

* Move SFF related functions from libata-core.c to libata-sff.c.

ata_[bmdma_]sff_port_ops, ata_devchk(), ata_dev_try_classify(),
ata_std_dev_select(), ata_tf_to_host(), ata_busy_sleep(),
ata_wait_after_reset(), ata_wait_ready(), ata_bus_post_reset(),
ata_bus_softreset(), ata_bus_reset(), ata_std_softreset(),
sata_std_hardreset(), ata_fill_sg(), ata_fill_sg_dumb(),
ata_qc_prep(), ata_dump_qc_prep(), ata_data_xfer(),
ata_data_xfer_noirq(), ata_pio_sector(), ata_pio_sectors(),
atapi_send_cdb(), __atapi_pio_bytes(), atapi_pio_bytes(),
ata_hsm_ok_in_wq(), ata_hsm_qc_complete(), ata_hsm_move(),
ata_pio_task(), ata_qc_issue_prot(), ata_host_intr(),
ata_interrupt(), ata_std_ports()

* Make ata_pio_queue_task() global as it's now called from
libata-sff.c.

* Move SFF related stuff in include/linux/libata.h and
drivers/ata/libata.h into one place. While at it, move timing
constants into the global enum definition and fortify comments a
bit.

This patch strictly moves stuff around and as such doesn't cause any
functional difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

make atapi_dmadir static

atapi_dmadir can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: implement libata.force module parameter

This patch implements libata.force module parameter which can
selectively override ATA port, link and device configurations
including cable type, SATA PHY SPD limit, transfer mode and NCQ.

For example, you can say "use 1.5Gbps for all fan-out ports attached
to the second port but allow 3.0Gbps for the PMP device itself, oh,
the device attached to the third fan-out port chokes on NCQ and
shouldn't go over UDMA4" by the following.

libata.force=2:1.5g,2.15:3.0g,2.03:noncq,udma4

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: move ata_set_mode() to libata-eh.c

Move ata_set_mode() to libata-eh.c. ata_set_mode() is surely an EH
action and will be more tightly coupled with the rest of error
handling. Move it to libata-eh.c.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-acpi: add ACPI _PSx method

ACPI spec (ver 3.0a, p289) requires IDE power on/off executes ACPI _PSx
methods. As recently most PATA drivers use libata, this patch adds _PSx
method support in libata. ACPI spec doesn't mention if SATA requires the
same _PSx method.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: Disable ATA8-ACS proposed Trusted Computing features by default

Historically word 48 in the identify data was used to mean 32bit I/O
was supported for VLB IDE etc. ATA8 reassigns this word to the Trusted
Computing Group, where it is used for TCG features. This means that
an ATA8 TCG drive is going to trigger 32bit I/O on some systems which
will be funny.

Anyway we need to sort this out ready for ATA8 so:
- Reorder the ata.h header a bit so the ata_version function occurs early
in it
- Make dword_io check the ATA version
- Add an ATA8 version checking TCG presence test

While we are at it the current drafts have a flaw where it may not be
possible to disable TCG features at boot (and opt out of the trusted
model) as TCG intends because it relies on presence of a different
optional feature (DCS). Handle this in software by refusing the TCG
commands if libata.allow_tpm is not set. (We must make it possible
as some environments such as proprietary VDR devices will doubtless
want to use it to lock up content)

Finally as with CPRM print a warning so that the user knows they may
not be able to full access and use the device.

Signed-off-by: Alan Cox <alan@redhat.com>

libata-acpi: add new hooks ata_acpi_dissociate() and ata_acpi_on_disable()

Add two hooks - ata_acpi_dissociate() which is called during driver
detach after the whole host is shutdown and ata_acpi_on_disable()
which is called when a device is disabled.

Signed-off-by: Tejun heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[libata] Link power management infrastructure

Device Initiated Power Management, which is defined
in SATA 2.5 can be enabled for disks which support it.
This patch enables DIPM when the user sets the link
power management policy to "min_power".

Additionally, libata drivers can define a function
(enable_pm) that will perform hardware specific actions to
enable whatever power management policy the user set up
for Host Initiated Power management (HIPM).
This power management policy will be activated after all
disks have been enumerated and intialized. Drivers should
also define disable_pm, which will turn off link power
management, but not change link power management policy.

Documentation/scsi/link_power_management_policy.txt has additional
information.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: add @timeout to ata_exec_internal[_sg]()

Add @timeout argument to ata_exec_internal[_sg](). If 0, default
timeout ata_probe_timeout is used.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp: extend ACPI support to cover PMP

Extend ata_acpi_associate_sata_port() such that it can handle PMP and
call it when PMP is attached and detached.

Build breakage when !CONFIG_ATA_ACPI was spotted and fixed by Petr
Vandrovec.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp: hook PMP support and enable it

Hook PMP support into libata and enable it. Connect SCR and probing
functions, and update ata_dev_classify() to detect PMP.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp: implement Port Multiplier support

Implement Port Multiplier support. To support PMP, a LLDD has to
supply ops->pmp_read() and pmp_write(). If non-null, ->pmp_attach and
->pmp_detach are called on PMP attach and detach, respectively.

->pmp_read/write() can be called while the port is frozen, so they
must be implemented by polling. This patch supplies several helpers
to ease ->pmp_read/write() implementation.

Also, irq_handler and error_handler must be PMP aware. Most of PMP
aware EH can be done by calling ata_pmp_do_eh() with appropriate
methods. PMP EH uses separate set of reset methods and this patch
implements standard prereset, hardreset and postreset methods.

This patch only implements PMP support. The next patch will integrate
PMP into the reset of libata and thus enable PMP support.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp-prep: implement sata_async_notification()

AN serves multiple purposes. For ATAPI, it's used for media change
notification. For PMP, for downstream PHY status change notification.
Implement sata_async_notification() which demultiplexes AN.

To avoid unnecessary port events, ATAPI AN is not enabled if PMP is
attached but SNTF is not available.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kriten Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp-prep: make a number of functions global to libata

Make a number of functions from libata-core.c and libata-eh.c global
to libata (drivers/ata/libata.h). These will be used by PMP.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-pmp-prep: add @new_class to ata_dev_revalidate()

Consider newly found class code while revalidating. PMP resetting
always results in valid class code and issuing PMP commands to
ATA/ATAPI device isn't very attractive. Add @new_class to
ata_dev_revalidate() and check class code for revalidation.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[libata] SCSI: simulator version, not device version, belongs in VPD

Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: add support for ATA_16 on ATAPI

Add support for issuing ATA_16 passthru commands to ATAPI devices
managed by libata. It requires the previous CDB length fix patch.

A boot/module parameter, "atapi_passthru16=0" can be used to globally
disable this feature, if ever desired.

tj: restructured __ata_scsi_queuecmd() according to Jeff's suggestion.

Signed-off-by: Mark Lord <liml@rtr.ca>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-link: linkify config/EH related functions

Make the following functions deal with ata_link instead of ata_port.

* ata_set_mode()
* ata_eh_autopsy() and related functions
* ata_eh_report() and related functions
* suspend/resume related functions
* ata_eh_recover() and related functions

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-link: linkify PHY-related functions

Make the following PHY-related functions to deal with ata_link instead
of ata_port.

* sata_print_link_status()
* sata_down_spd_limit()
* ata_set_sata_spd_limit() and friends
* sata_link_debounce/resume()
* sata_scr_valid/read/write/write_flush()
* ata_link_on/offline()

This patch introduces no behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: implement EH fast drain

In most cases, when EH is scheduled, all in-flight commands are
aborted causing EH to kick in immediately. However, in some cases
(especially with PMP), it's unclear which commands are affected by the
error condition and although aborting all in-flight commands work, it
isn't optimal and may cause unnecessary disruption. On the other
hand, waiting for in-flight commands to drain themselves can take up
to 30seconds.

This patch implements EH fast drain to handle such situations. It
gives in-flight commands some time to finish up but doesn't wait for
too long. After EH is scheduled, fast drain timer is started and if
no other completion occurs in ATA_EH_FASTDRAIN_INTERVAL all in-flight
commands are aborted. If any completion occurred in the interval, the
port is given another interval to finish up itself.

Currently ATA_EH_FASTDRAIN_INTERVAL is 3 secs which should be enough
for finishing up most commands.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: improve SCSI scan failure handling

SCSI scan may fail due to memory allocation failure even if EH is not
in progress. Due to use of GFP_ATOMIC in SCSI scan path, allocation
failure isn't too rare especially while probing multiple devices at
once which is the case when a bunch of devices are connected to PMP.

This patch moves SCSI scan failure detetion logic from
ata_scsi_hotplug() to ata_scsi_scan_host() and implement synchronous
scan behavior. The synchronous path sleeps briefly and repeats SCSI
scan if some devices aren't attached properly. It contains robust
retry loop to minimize the chance of device misdetection during boot
and falls back to async retry if everything fails.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-acpi: implement _GTM/_STM support

Implement _GTM/_STM support. acpi_gtm is added to ata_port which
stores _GTM parameters over suspend/resume cycle. A new hook
ata_acpi_on_suspend() is responsible for storing _GTM parameters
during suspend. _STM is executed in ata_acpi_on_resume(). With this
change, invoking _GTF is safe on IDE hierarchy and acpi_sata check
before _GTF is removed.

ata_acpi_gtm() and ata_acpi_stm() implementation is taken from Alan
Cox's pata_acpi implementation. ata_acpi_gtm() is fixed such that the
result parameter is not shifted by sizeof(union acpi_object).

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: reimplement ACPI invocation

This patch reimplements ACPI invocation such that, instead of
exporting ACPI details to the rest of libata, ACPI event handlers -
ata_acpi_on_resume() and ata_acpi_on_devcfg() - are used. These two
functions are responsible for determining whether specific ACPI method
is used and when.

On resume, _GTF is scheduled by setting ATA_DFLAG_ACPI_PENDING device
flag. This is done this way to avoid performing the action on wrong
device device (device swapping while suspended).

On every ata_dev_configure(), ata_acpi_on_devcfg() is called, which
performs _SDD and _GTF. _GTF is performed only after resuming and, if
SATA, hardreset as the ACPI spec specifies. As _GTF may contain
arbitrary commands, IDENTIFY page is re-read after _GTF taskfiles are
executed.

If one of ACPI methods fails, ata_acpi_on_devcfg() retries on the
first failure. If it fails again on the second try, ACPI is disabled
on the device. Note that successful configuration clears ACPI failed
status.

With all feature checks moved to the above two functions,
do_drive_set_taskfiles() is trivial and thus collapsed into
ata_acpi_exec_tfs(), which is now static and converted to return the
number of executed taskfiles to be used by ata_acpi_on_resume(). As
failures are handled properly, ata_acpi_push_id() now returns -errno
on errors instead of unconditional zero.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-acpi: implement ata_acpi_associate()

* Add acpi_handle to ata_host and ata_port. Rename
ata_device->obj_handle to ->acpi_handle and move it above such that
it doesn't get cleared on reconfiguration.

* Replace ACPI node association which ata_acpi_associate() which is
called once during host initialization. Unlike the previous
implementation, ata_acpi_associate() uses ATA_FLAG_ACPI_SATA to
choose between IDE or SATA ACPI hierarchy and uses simple child look
up instead of recursive walk to match the nodes. This is way safer
and simpler. Please read the following message for more info.

http://article.gmane.org/gmane.linux.ide/17554

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: remove libata.spindown_compat

With STANDBYDOWN tracking added, libata.spindown_compat isn't
necessary anymore. If userspace shutdown(8) issues STANDBYNOW, libata
warns. If userspace shutdown(8) doesn't issue STANDBYNOW, libata does
the right thing. Userspace can tell whether kernel supports spindown
by testing whether sysfs node manage_start_stop exists as before.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: separate out ata_dev_reread_id()

Separate out ata_dev_reread_id() from ata_dev_revalidate().
ata_dev_reread_id() reads IDENTIFY page and determines whether the
same device is still there. ata_dev_revalidate() reconfigures after
reread completes. This will be used by ACPI update.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-acpi: clean up parameters and misc stuff

This patch cleans up libata-acpi such that it looks similar to other
libata files. This patch doesn't introuce any behavior changes.

* make libata-acpi functions take ata_device instead of ata_port +
device index
* s/atadev/dev/
* de-indent local variable declarations

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-acpi: s/CONFIG_SATA_ACPI/CONFIG_ATA_ACPI/

ACPI applies to both SATA and PATA. Drop the 'S' from the config
variable.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: implement libata.spindown_compat

Now that libata uses sd->manage_start_stop, libata spins down disk on
shutdown. In an attempt to compensate libata's previous shortcoming,
some distros sync and spin down disks attached via libata in their
shutdown(8). Some disks spin back up just to spin down again on
STANDBYNOW1 if the command is issued when the disk is spun down, so
this double spinning down causes problem.

This patch implements module parameter libata.spindown_compat which,
when set to one (default value), prevents libata from spinning down
disks on shutdown thus avoiding double spinning down. Note that
libata spins down disks for suspend to mem and disk, so with
libata.spindown_compat set to one, disks should be properly spun down
in all cases without modifying shutdown(8).

shutdown(8) should be fixed eventually. Some drive do spin up on
SYNCHRONZE_CACHE even when their cache is clean. Those disks
currently spin up briefly when sd tries to shutdown the device and
then the machine powers off immediately, which can't be good for the
head. We can't skip SYNCHRONIZE_CACHE during shudown as it can be
dangerous data integrity-wise.

So, this spindown_compat parameter is already scheduled for removal by
the end of the next year and here's what shutdown(8) should do.

* Check whether /sys/modules/libata/parameters/spindown_compat
exists. If it does, write 0 to it.

* For each libata harddisk {
* Check whether /sys/class/scsi_disk/h:c:i:l/manage_start_stop
exists. Iff it doesn't, synchronize cache and spin the disk
down as before.
}

The above procedure will make shutdown(8) work properly with kernels
before this change, ones with this workaround and later ones without
it.

To accelerate shutdown(8) updates, if the compat mode is in use, this
patch prints BIG FAT warning for five seconds during shutdown (the
optimal interval to annoy the user just the right amount discovered by
hours of tireless usability testing).

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: kill probe_ent and related helpers

All drivers are converted to new init model. Kill probe_ent,
ata_device_add() and ata_pci_init_native_mode().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: separate out ata_host_alloc() and ata_host_register()

Reorganize ata_host_alloc() and its subroutines into the following
three functions.

* ata_host_alloc() : allocates host and its ports. shost is not
registered automatically.

* ata_scsi_add_hosts() : allocates and adds shosts associated with an
ATA host. Used by ata_host_register().

* ata_host_register() : takes a fully initialized ata_host structure
and registers it to libata layer and probes it.

Only ata_host_alloc() and ata_host_register() are exported.
ata_device_add() is rewritten using the above functions. This patch
does not introduce any observable behavior change. Things worth
mentioning.

* print_id is assigned at registration time and LLDs are allowed to
overallocate ports and reduce host->n_ports during initialization.
ata_host_register() will throw away unused ports automatically.

* All SCSI host initialization stuff now resides in
ata_scsi_add_hosts() in libata-scsi.c, where it should be.

* ipr is now the only user of ata_host_init(). Either kill it by
converting ipr to use ata_host_alloc() and friends or rename and
move it to libata-scsi.c

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[libata] Disable ACPI by default; fix namespace problems

Not yet ready to turn on ATA ACPI by default, for either PATA or SATA.

Also, rename the global-scope module parameter variable 'noacpi' to
something more libata-specific, reducing the potential for namespace
collision.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

SiS warning fixes

Somehow the sis_info133 external definition ended up in libata.h and that
was included by both drivers. However libata.h contains libata-* specific
internals and clashing defines like DRV_NAME so this makes a mess. Move
the extern into the C file and remove the warnings

[akpm@linux-foundation.org: create sis.h to avoid extern-decl-in-C]
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: kill ATA_DNXFER_ANY

ATA_DNXFER_ANY isn't used anymore. Kill it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: improve ata_down_xfermask_limit()

Make ata_down_xfermask_limit() accept @sel instead of @force_pio0.
@sel selects how the xfermask limit will be adjusted. The following
selectors are defined.

* ATA_DNXFER_PIO : only speed down PIO
* ATA_DNXFER_DMA : only speed down DMA, don't cause transfer mode change
* ATA_DNXFER_40C : apply 40c cable limit
* ATA_DNXFER_FORCE_PIO : force PIO
* ATA_DNXFER_FORCE_PIO0 : force PIO0 (same as original with @force_pio0 == 1)
* ATA_DNXFER_ANY : same as original with @force_pio0 == 0

Currently, only ANY and FORCE_PIO0 are used to maintain the original
behavior. Other selectors will be used later to improve EH speed down
sequence.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: ACPI _SDD support

_SDD (Set Device Data) is an ACPI method that is used to tell the
firmware what the identify data is of the device that is attached to
the port. It is an optional method, and it's ok for it to be missing.
Because of this, we always return success from the routine that calls
this method, even if the execution fails.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
(cherry picked from 39aa79e0a1f5f2e28aa341f035940746a98b45b1 commit)

[PATCH] libata: ACPI and _GTF support

_GTF is an acpi method that is used to reinitialize the drive. It returns
a task file containing ata commands that are sent back to the drive to restore
it to boot up defaults.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
(cherry picked from 9c69cab24b51a89664f4c0dfaf8a436d32117624 commit)

[libata] Shuffle DRV_xxx in core and SiS drivers, to kill warnings

Signed-off-by: Jeff Garzik <jeff@garzik.org>

fix CONFIG_SATA_SIS=y compile error

Static code shouldn't be used from other modules.

drivers/built-in.o: In function `sis_init_one':
sata_sis.c:(.text+0x7634cd): undefined reference to `sis_info133'
sata_sis.c:(.text+0x7634d6): undefined reference to `sis_info133'

While I was at it, I also moved the prototype of this struct to a header
file.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: always use polling IDENTIFY

libata switched to IRQ-driven IDENTIFY when IRQ-driven PIO was
introduced. This has caused a lot of problems including device
misdetection and phantom device.

ATA_FLAG_DETECT_POLLING was added recently to selectively use polling
IDENTIFY on problemetic drivers but many controllers and devices are
affected by this problem and trying to adding ATA_FLAG_DETECT_POLLING
for each such case is diffcult and not very rewarding.

This patch makes libata always use polling IDENTIFY. This is
consistent with libata's original behavior and drivers/ide's behavior.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: prepare ata_sg_clean() for invocation from EH

Make ata_sg_clean() global and don't allow NCQ for internal commands.

Signed-off-by: Tejun Heo <htejun@gmail.com>

[PATCH] libata: separate out rw ATA taskfile building into ata_build_rw_tf()

Separate out rw ATA taskfile building from ata_scsi_rw_xlat() into
ata_build_rw_tf(). This will be used to improve media error handling.

Signed-off-by: Tejun Heo <htejun@gmail.com>

[PATCH] libata: implement ata_exec_internal_sg()

Sg'ify ata_exec_internal() and call it ata_exec_internal_sg().
Wrapper function around ata_exec_internal_sg() is implemented to
provide ata_exec_internal() interface.

Signed-off-by: Tejun Heo <htejun@gmail.com>

[PATCH] libata: implement ata_tf_read_block()

Implement ata_tf_read_block().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: implement presence detection via polling IDENTIFY

On some controllers (ICHs in piix mode), there is *NO* reliable way to
determine device presence other than issuing IDENTIFY and see how the
transaction proceeds by watching the TF status register.

libata acted this way before irq-pio and phantom devices caused very
little problem but now that IDENTIFY is performed using IRQ drive PIO,
such phantom devices now result in multiple 30sec timeouts during
boot.

This patch implements ATA_FLAG_DETECT_POLLING. If a LLD sets this
flag, libata core issues the initial IDENTIFY in polling mode and if
the initial data transfer fails w/ HSM violation, the port is
considered to be empty thus replicating the old libata and IDE
behavior.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: convert @post_reset to @flags in ata_dev_read_id()

Make ata_dev_read_id() take @flags instead of @post_reset. Currently
there is only one flag defined - ATA_READID_POSTRESET, which is
equivalent to @post_reset. This is preparation for polling presence
detection.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: implement ATA_EHI_PRINTINFO

Implement ehi flag ATA_EHI_PRINTINFO. This flag is set when device
configuration needs to print out device info. This used to be handled
by @print_info argument to ata_dev_configure() but LLDs also need to
know about it in ->dev_config() callback.

This patch replaces @print_info w/ ATA_EHI_PRINTINFO and make sata_sil
print workaround messages only on the initial configuration.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[PATCH] libata: move ata_irq_on() into libata-sff.c

ata_irq_on() isn't used outside of libata core layer. The function is
TF/SFF interface specific but currently used by core path with some
hack too. Move it from include/linux/libata.h to
drivers/ata/libata-sff.c.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

WorkStruct: Pass the work_struct pointer instead of context data

Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct. This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function. This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated.. This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems. But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default. Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>

[PATCH] libata: unexport ata_dev_revalidate()

ata_dev_revalidate() isn't used outside of libata core. Unexport it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: Grand renaming.

The biggest change is that ata_host_set is renamed to ata_host.

* ata_host_set => ata_host
* ata_probe_ent->host_flags => ata_probe_ent->port_flags
* ata_probe_ent->host_set_flags => ata_probe_ent->_host_flags
* ata_host_stats => ata_port_stats
* ata_port->host => ata_port->scsi_host
* ata_port->host_set => ata_port->host
* ata_port_info->host_flags => ata_port_info->flags
* ata_(.*)host_set(.*)\(\) => ata_\1host\2()

The leading underscore in ata_probe_ent->_host_flags is to avoid
reusing ->host_flags for different purpose. Currently, the only user
of the field is libata-bmdma.c and probe_ent itself is scheduled to be
removed.

ata_port->host is reused for different purpose but this field is used
inside libata core proper and of different type.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

Move libata to drivers/ata.