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: NTejun Heo <tj@kernel.org>
Acked-by: NJeff Garzik <jgarzik@pobox.com>

Implement ata_scsi_unlock_native_capacity() which will be called
through SCSI layer when block layer notices that partitions on a
device extend beyond the end of the device.  It requests EH to unlock
HPA, waits for completion and returns the current device capacity.

This allows libata to unlock HPA on demand instead of having to decide
whether to unlock upfront.  Unlocking on demand is safer than
unlocking by upfront because some BIOSes write private data to the
area beyond HPA limit.  This was suggested by Ben Hutchings.
Signed-off-by: NTejun Heo <tj@kernel.org>
Suggested-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Add dump_id libata.force parameter.  If specified, libata dumps full
IDENTIFY data during device configuration.  This is to aid debugging.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Larry Baker <baker@usgs.gov>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Make BMDMA optional depending on new config variable CONFIG_ATA_BMDMA.
In Kconfig, drivers are grouped into five groups - non-SFF native, SFF
w/ custom DMA interface, SFF w/ BMDMA, PIO-only SFF, and generic
fallback / legacy ones.  Kconfig and Makefile are reorganized
according to the groups and ordered alphabetically inside each group.

ata_ioports.bmdma_addr and ata_port.bmdma_prd[_dma] are put into
CONFIG_ATA_BMDMA, as are all bmdma related ops, variables and
functions.

This increase the binary size slightly when BMDMA is enabled but on
both native-only and PIO-only configurations the size is slightly
reduced.  Either way, the size difference is insignificant.  This
change is more meaningful to signify the separation between SFF and
BMDMA and as a tool to verify the separation.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Separate out ata_pci_bmdma_prepare_host() and ata_pci_bmdma_init_one()
from their SFF counterparts.  SFF ones no longer try to initialize
BMDMA or set PCI master.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Separate out BMDMA irq handler from SFF irq handler.  The misnamed
host_intr() functions are renamed to ata_sff_port_intr() and
ata_bmdma_port_intr().  Common parts are factored into
__ata_sff_port_intr() and __ata_sff_interrupt() and used by sff and
bmdma interrupt routines.

All BMDMA drivers now use ata_bmdma_interrupt() or
ata_bmdma_port_intr() while all non-BMDMA SFF ones use
ata_sff_interrupt() or ata_sff_port_intr().

For now, ata_pci_sff_init_one() uses ata_bmdma_interrupt() as it's
used by both SFF and BMDMA drivers.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ata_sff_irq_clear() is BMDMA specific.  Rename it to
ata_bmdma_irq_clear(), move it to ata_bmdma_port_ops and make
->sff_irq_clear() optional.

Note: ata_bmdma_irq_clear() is actually only needed by ata_piix and
      possibly by sata_sil.  This should be moved to respective low
      level drivers later.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Separate out ata_bmdma_qc_issue() from ata_sff_qc_issue() such that
ata_sff_qc_issue() only deals with non-BMDMA SFF protocols (PIO and
nodata) while ata_bmdma_qc_issue() deals with the BMDMA protocols and
uses ata_sff_qc_issue() for non-DMA commands.  All the users are
updated accordingly.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

struct ata_prd and ap->prd are BMDMA specific.  Add bmdma_ prefix to
them and move them inside CONFIG_ATA_SFF.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Both qc_prep functions deal only with BMDMA PRD setup and PIO only SFF
drivers don't need them.  Rename to ata_bmdma_[dumb_]qc_prep() and
relocate.

All usages are renamed except for pdc_adma and sata_qstor.  Those two
drivers are not BMDMA drivers and don't need to call BMDMA qc_prep
functions.  Calls to ata_sff_qc_prep() in the two drivers are removed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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

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

ap->[last_]ctl are specific to SFF controllers.  Put them inside
CONFIG_ATA_SFF and move initialization into ata_sff_port_init().
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

->drain_fifo() is SFF specific.  Rename and relocate it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

When BMDMA initialization failed or BMDMA was not available for
whatever reason, bmdma_addr was left at zero and used as an indication
that BMDMA shouldn't be used.  This leads to the following problems.

p1. For BMDMA drivers which don't use traditional BMDMA register,
    ata_bmdma_mode_filter() incorrectly inhibits DMA modes.  Those
    drivers either have to inherit from ata_sff_port_ops or clear
    ->mode_filter explicitly.

p2. non-BMDMA drivers call into BMDMA PRD table allocation.  It
    doesn't actually allocate PRD table if bmdma_addr is not
    initialized but is still confusing.

p3. For BMDMA drivers which don't use traditional BMDMA register, some
    methods might not be invoked as expected (e.g. bmdma_stop from
    ata_sff_post_internal_cmd()).

p4. SFF drivers w/ custom DMA interface implement noop BMDMA ops
    worrying libata core might call into one of them.

These problems are caused by the muddy line between SFF and BMDMA and
the assumption that all BMDMA controllers initialize bmdma_addr.

This patch fixes p1 and p2 by removing the bmdma_addr assumption and
moving prd allocation to BMDMA port start.  Later patches will fix the
remaining issues.

This patch improves BMDMA initialization such that

* When BMDMA register initialization fails, falls back to PIO instead
  of failing.  ata_pci_bmdma_init() never fails now.

* When ata_pci_bmdma_init() falls back to PIO, it clears
  ap->mwdma_mask and udma_mask instead of depending on
  ata_bmdma_mode_filter().  This makes ata_bmdma_mode_filter()
  unnecessary thus resolving p1.

* ata_port_start() which actually is BMDMA specific is moved to
  ata_bmdma_port_start().  ata_port_start() and ata_sff_port_start()
  are killed.

* ata_sff_port_start32() is moved and renamed to
  ata_bmdma_port_start32().

Drivers which no longer call into PRD table allocation are...

  pdc_adma, sata_inic162x, sata_qstor, sata_sx4, pata_cmd640 and all
  drivers which inherit from ata_sff_port_ops.

pata_icside sets ->port_start to ATA_OP_NULL as it doesn't need PRD
but is a BMDMA controller and doesn't have custom port_start like
other such controllers.

Note that with the previous patch which makes all and only BMDMA
drivers inherit from ata_bmdma_port_ops, this change doesn't break
drivers which need PRD table.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Reorder functions such that SFF and BMDMA functions are grouped.
While at it, s/BMDMA/SFF in a few comments where it actually meant
SFF.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ATA_FLAG_DISABLED is only used by drivers which don't use
->error_handler framework and is largely broken.  Its only meaningful
function is to make irq handlers skip processing if the flag is set,
which is largely useless and even harmful as it makes those ports more
likely to cause IRQ storms.

Kill ATA_FLAG_DISABLED and makes the callers disable attached devices
instead.  ata_port_probe() and ata_port_disable() which manipulate the
flag are also killed.

This simplifies condition check in IRQ handlers.  While updating IRQ
handlers, remove ap NULL check as libata guarantees consecutive port
allocation (unoccupied ports are initialized with dummies) and
long-obsolete ATA_QCFLAG_ACTIVE check (checked by ata_qc_from_tag()).
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Now, with the introduction of the sff_set_devctl() method, we can
use it in sff_irq_on() method too -- that way its implementations
in 'pata_bf54x' and 'pata_scc' become virtually identical to
ata_sff_irq_on().  The sff_irq_on() method now becomes quite
superfluous, and the only reason not to remove it completely is
the existence of the 'pata_octeon_cf' driver which implements it
as an empty function. Just make the method optional then, with
ata_sff_irq_on() becoming generic taskfile-bound function, still
global for the 'pata_bf54x' driver to be able to call it from its
thaw() and postreset() methods.

While at it, make the sff_irq_on() method and ata_sff_irq_on() return
'void' as the result is always ignored anyway.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The set of libata's taskfile access methods is clearly incomplete as
it lacks a method to write to the device control register -- which
forces drivers like 'pata_bf54x' and 'pata_scc' to implement more
"high level" (and more weighty) methods like freeze() and postreset().

So, introduce the optional sff_set_devctl() method which the drivers
only have to implement if the standard iowrite8() can't be used (just
like the existing sff_check_altstatus() method) and make use of it
in the freeze() and postreset() method implementations (I could also
have used it in softreset() method but it also reads other taskfile
registers without using tf_read() making that quite pointless);
this makes freeze() method implementations in the 'pata_bf54x' and
'pata_scc' methods virtually identical to ata_sff_freeze(), so we
can get rid of them completely.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

There are some SATA devices which take relatively long to get out of
0xff status after reset.  In libata, this timeout is determined by
ATA_TMOUT_FF_WAIT.  Quantum GoVault is the worst requring about 2s for
reliable detection.  However, because 2s 0xff timeout can introduce
rather long spurious delay during boot, libata has been compromising
at the next longest timeout of 800ms for HHD424020F7SV00 iVDR drive.

Now that parallel scan is in place for common drivers, libata can
afford 2s 0xff timeout.  Use 2s 0xff timeout if parallel scan is
enabled.

Please note that the chance of spurious wait is pretty slim w/ working
SCR access so this will only affect SATA controllers w/o SCR access
which isn't too common these days.

Please read the following thread for more information on the GoVault
drive.

  http://thread.gmane.org/gmane.linux.ide/14545/focus=14663Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

... since I see no callers of it.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Some BIOSes don't configure HPA during boot but do so while resuming.
This causes harddrives to shrink during resume making libata detach
and reattach them.  This can be worked around by unlocking HPA if old
size equals native size.

Add ATA_DFLAG_UNLOCK_HPA so that HPA unlocking can be controlled
per-device and update ata_dev_revalidate() such that it sets
ATA_DFLAG_UNLOCK_HPA and fails with -EIO when the above condition is
detected.

This patch fixes the following bug.

  https://bugzilla.kernel.org/show_bug.cgi?id=15396Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NOleksandr Yermolenko <yaa.bta@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This allows parallel scan and the like to be set without having to stop
using the existing full helper functions. This patch merely adds the argument
and fixes up the callers. It doesn't undo the special cases already in the
tree or add any new parallel callers.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Traditional IDE interface sucks in that it doesn't have a reliable IRQ
pending bit, so if the controller raises IRQ while the driver is
expecting it not to, the IRQ won't be cleared and eventually the IRQ
line will be killed by interrupt subsystem.  Some controllers have
non-standard mechanism to indicate IRQ pending so that this condition
can be detected and worked around.

This patch adds an optional operation ->sff_irq_check() which will be
called for each port from the ata_sff_interrupt() if an unexpected
interrupt is received.  If the operation returns %true,
->sff_check_status() and ->sff_irq_clear() will be cleared for the
port.  Note that this doesn't mark the interrupt as handled so it
won't prevent IRQ subsystem from killing the IRQ if this mechanism
fails to clear the spurious IRQ.

This patch also implements ->sff_irq_check() for ata_piix.  Note that
this adds slight overhead to shared IRQ operation as IRQs which are
destined for other controllers will trigger extra register accesses to
check whether IDE interrupt is pending but this solves rare screaming
IRQ cases and for some curious reason also helps weird BIOS related
glitch on Samsung n130 as reported in bko#14314.

  http://bugzilla.kernel.org/show_bug.cgi?id=14314

* piix_base_ops dropped as suggested by Sergei.

* Spurious IRQ detection doesn't kick in anymore if polling qc is in
  progress.  This provides less protection but some controllers have
  possible data corruption issues if the wrong register is accessed
  while a command is in progress.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NJohannes Stezenbach <js@sig21.net>
Reported-by: NHans Werner <hwerner4@gmx.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Interestingly, when SIDPR is used in ata_piix, writes to DET in
SControl sometimes get ignored leading to detection failure.  Update
sata_link_resume() such that it reads back SControl after clearing DET
and retry if it's not clear.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: Nfengxiangjun <fengxiangjun@neusoft.com>
Reported-by: NJim Faulkner <jfaulkne@ccs.neu.edu>
Cc: stable@kernel.org
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This patch modifies scsi_host_template->change_queue_depth so that
it takes an argument indicating why it is being called. This will be
used so that if a LLD needs to do some extra processing when
handling queue fulls or later ramp ups, it can do so.

This is a simple port of the drivers setting a change_queue_depth
callback. In the patch I just have these LLDs adjust the queue depth
if the user was requesting it.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>

[Vasu.Dev: v2
	Also converted pmcraid_change_queue_depth and then verified
all modules compile  using "make allmodconfig" for any new build
warnings on X86_64.

	Updated original description after combing two original
patches from Mike to make this patch git bisectable.]
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
[jejb: fixed up 53c700]
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This brings struct ata_device in-line with struct ata_{port,host}.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

If ATA device failed FLUSH, it means that the device failed to write
out some amount of data and the error needs to be reported to upper
layers. As retries can't recover the lost data, FLUSH failures need to
be reported immediately in general.

However, if FLUSH fails due to transmission errors, the FLUSH needs to
be retried; otherwise, filesystems may switch to RO mode and/or raid
array may drop a drive for a random transmission glitch.

This condition can be rather easily reproduced on certain ahci
controllers which go through a PHY event after powersave mode switch +
ext4 combination.  Powersave mode switch is often closely followed by
flush from the filesystem failing the FLUSH with ATA bus error which
makes the filesystem code believe that data is lost and drop to RO
mode.  This was reported in the following bugzilla bug.

  http://bugzilla.kernel.org/show_bug.cgi?id=14543

This patch makes libata EH retry FLUSH if it wasn't failed by the
device.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NAndrey Vihrov <andrey.vihrov@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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

Currently libata-acpi can only filter DIPM among SATA feature enables
via _GTF.  This patch adds the capability to filter out FPDMA non-zero
offset, in-order guarantee and auto-activation.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

We're about to add more SATA_* and ATA_ACPI_FILTER_* constants.
Reformat them in preparation.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This was a hack to give userland shutdown tools time to drop manual
spindown.  All popular distros updated quite some time ago and the due
is well passed.  Drop it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Hopefully results in fewer on-the-wire FIS's and no breakage.  We'll see!
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

On certain configurations, HPA isn't or can't be unlocked during
probing but it somehow ends up unlocked afterwards.  In the following
thread, the problem can be reliably reproduced after resuming from
STR.  The BIOS turns on HPA during boot but forgets to do it during
resume.

  http://thread.gmane.org/gmane.linux.kernel/858310

This patch updates libata revalidation such that it considers native
n_sectors.  If the device size has increased to match native
n_sectors, it's assumed that HPA has been unlocked involuntarily and
the device is recognized as the same one.  This should be fairly safe
while nicely working around the problem.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NChristof Warlich <christof@warlich.name>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

PIONEER DVD-RW DVRTD08 times out SETXFER if no media is present.  The
device is SATA and simply skipping SETXFER works around the problem.
Implement ATA_HORKAGE_NOSETXFER and apply it to the device.

Reported by Moritz Rigler in the following thread.

  http://thread.gmane.org/gmane.linux.ide/36790

and by Lars in bko#9540.

Updated to whine and ignore NOSETXFER if PATA component is detected as
suggested by Alan Cox.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NMoritz Rigler <linux-ide@momail.e4ward.com>
Reported-by: NLars <lars21ce@gmx.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The legacy old IDE ioctl API for this is a bit primitive so we try
and map stuff sensibly onto it.

- Set PIO over DMA devices to report 32bit
- Add ability to change the PIO32 settings if the controller permits it
- Add that functionality into the sff drivers
- Add that functionality into the VLB legacy driver
- Turn on the 32bit PIO on the ninja32 and add support there
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Fix misspelling of firmware.
Signed-off-by: NNick Andrew <nick@nick-andrew.net>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

On a timeout call a device specific handler early in the recovery so that
we can complete and process successful commands which timed out due to IRQ
loss or the like rather more elegantly.

[Revised to exclude the timeout handling on a few devices that inherit from
 SFF but are not SFF enough to use the default timeout handler]
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

If the device is signalling that there is data to drain after an error we
should read the bytes out and throw them away. Without this some devices
and controllers get wedged and don't recover.

Based on earlier work by Mark Lord
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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