* Clearing IRQ from ata_sff_error_handler() is necessary only when the
  port is gonna be thawed before performing EH actions and some
  controllers don't like being accessed after certain failure modes
  until they're reset.  Clear IRQ iff the port is being thawed.

* When the controller succesfully indicated bus error, the point of
  thawing doesn't matter.  Move thawing inside bmdma part of EH.  This
  is a bit ugly but will ease code reorganization later.

* Remove the unneeded ata_sff_sync().
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

We don't need to stall and wait after loading the task file and before
issuing a command, so don't do it. This shows up on profiles and is not
needed.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

page_mapping() check this via VM_BUG_ON(PageSlab(page)) so we bug here
with the according debuging turned on.

Future TODO: replace this with a flush_dcache_page_for_pio() API
Signed-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
Cc: stable@kernel.org

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>

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

On configurations where IRQ line is shared with a different
controller, spurious IRQs may happen continuously.  The message was
put there primarily for debugging anyway.  Kill it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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

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

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

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

The script does the followings.

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

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

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

The conversion was done in the following steps.

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

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

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

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

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

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

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

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

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

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

Commit 27943620 introduced spurious
IRQ handling but it has a race condition where valid completion can be
lost while trying to clear spurious IRQ leading to occassional command
timeouts.

This patch improves SFF interrupt handler such that

1. Once BMDMA HSM is stopped, the condition is never considered
   spurious.  As there's no way to resume stopped BMDMA HSM, if device
   status doesn't agree with BMDMA status, the only way out is
   aborting the command (otherwise, it will just end up timing out).

2. ap->ops->sff_check_status() can be safely called to clear spurious
   device IRQ as it atomically returns completion status but BMDMA IRQ
   status can't be cleared in safe way if command is in flight.  After
   a spurious IRQ, call ap->ops->sff_irq_clear() only if the
   respective device is idle and retry completion if
   sff_check_status() indicates command completion.

Please note that ata_piix uses bmdma_status for sff_irq_check() and #2
won't weaken spurious IRQ handling even with in-flight command because
if bmdma_status indicates IRQ pending but device status is not on
spurious check, the next IRQ handler invocation will abort the command
due to #1.

This fixes bko#15537.

   https://bugzilla.kernel.org/show_bug.cgi?id=15537Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Andrew Benton <b3nton@gmail.com>
Cc: Petr Uzel <petr.uzel@centrum.cz>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
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>

host->ports[i] is never NULL if i < host->n_ports and non-NULL return
from ata_qc_from_tag() guarantees that the returned qc is active.
Drop unnecessary tests.

Superflous () dropped as suggested by Sergei.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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

flush_dcache_page() must be called after (!ATA_TFLAG_WRITE) the
data copying to avoid D-cache aliasing with user space or I-D cache
coherency issues (when reading data from an ATA device using PIO,
the kernel dirties the D-cache but there is no flush_dcache_page()
required on Harvard architectures).
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

When we drain data from a device to clear DRQ during error recovery,
the number of bytes reported as drained is too low by a factor of 2
because the count is actually reporting the number of words drained,
not bytes. Fix this.
Signed-off-by: NRobert Hancock <hancockrwd@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

In libata-sff, ata_sff_post_internal_cmd() directly calls ata_bmdma_stop()
instead of ap->ops->bmdma_stop(). This can be a problem for controllers
that use their own bmdma_stop for which the generic sff one isn't suitable
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NJeff Garzik <jgarzik@redhat.com>

Comment spelling fixes and whitespace adjustment.
Signed-off-by: NKrzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

In libata-sff, ata_sff_post_internal_cmd() directly calls ata_bmdma_stop()
instead of ap->ops->bmdma_stop(). This can be a problem for controllers
that use their own bmdma_stop for which the generic sff one isn't suitable
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Handling of the trailing byte in ata_sff_data_xfer() is suboptimal bacause:

- it always initializes the padding buffer to 0 which is not really needed in
  both the read and write cases;

- it has to use memcpy() to transfer a single byte from/to the padding buffer;

- it uses io{read|write}16() accessors which swap bytes on the big endian CPUs
  and so have to additionally convert the data from/to the little endian format
  instead of using io{read|write}16_rep() accessors which are not supposed to
  change the byte ordering.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
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>

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>

libata keeps a shadow copy of the ATA CTL register (which is write only),
and only writes to the hardware when the required value doesn't match
the shadow. However this copy wasn't being maintained when performing
reset functions. This could cause problems for the first operation after
a reset when the correct value might not be written to the CTL register.

This problem was observed when hotplugging a drive: the identify command
was being issued with interrupts enabled, when they should have been
disabled.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Commit 871af121 (libata: Add 32bit
PIO support) has caused all kinds of errors on the ATAPI devices, so
it has been empirically proven that one shouldn't try to read/write
an extra data word when a device is not expecting it already. "Don't
do it then"; however, still use a chance to do 32-bit read/write one
last time when there are exactly 3 trailing bytes.

Oh, and stop pointlessly swapping the bytes to and fro on big-endian
machines by using io*_rep() accessors which shouldn't byte-swap.

This patch should fix the kernel.org bug #12609.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Asus Pundit-R with atiixp controller has the second port missing and,
very unusually, its status is stuck at 0x7f and all others at 0.  This
meanst that it fails TF access test but gets detected as a disk due to
classification code check and then evades polling IDENTIFY presence
detection thanks to the missing BSY in the status value causing
excessive delays during boot.

This patch makes libata-sff HSM set NODEV_HINT if the status is 0x7f
to make polling IDENTIFY presence detection work for these machines.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The EH message for NODEV_HINT path was describing the opposite
condition.  Fix it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This patch fixes a wrong WARN_ON that was triggered by 32bit PIO support:
WARNING: at drivers/ata/libata-sff.c:1017 ata_sff_hsm_move+0x45e/0x750()

__atapi_pio_bytes simply doesnt know enough to decide if there is a bug.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Convert WARN_ON() on command issue/completion paths to WARN_ON_ONCE()
so that libata doesn't spam the machine even when one of those
conditions triggers repeatedly.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This matters for some controllers and in one or two cases almost doubles
PIO performance. Add a bmdma32 operations set we can inherit and activate
it for some controllers
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Currently libata uses four methods to detect device presence.

1. PHY status if available.
2. TF register R/W test (only promotes presence, never demotes)
3. device signature after reset
4. IDENTIFY failure detection in SFF state machine

Combination of the above works well in most cases but recently there
have been a few reports where a phantom device causes unnecessary
delay during probe.  In both cases, PHY status wasn't available.  In
one case, it passed #2 and #3 and failed IDENTIFY with ATA_ERR which
didn't qualify as #4.  The other failed #2 but as it passed #3 and #4,
it still caused failure.

In both cases, phantom device reported diagnostic failure, so these
cases can be safely worked around by considering any !ATA_DRQ IDENTIFY
failure as NODEV_HINT if diagnostic failure is set.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ata_sff_post_internal_cmd() needs to grab port lock before calling
ata_bmdma_stop() and also need to clear hsm_task_state.  Fix it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

On HSM_ST_ERR, ata_hsm_move() triggers WARN_ON() if AC_ERR_DEV or
AC_ERR_HSM is not set.  PHY events may trigger HSM_ST_ERR with other
error codes and, with or without it, there just isn't much reason to
do WARN_ON() on it.  Even if error code is not set there, core EH
logic won't have any problem dealing with the error condition.

OSDL bz#11065 reports this problem.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

libata has been using mix of jiffies and msecs for time druations.
This is getting confusing.  As writing sub HZ values in jiffies is
PITA and msecs_to_jiffies() can't be used as initializer, unify unit
for all time durations to msecs.  So, durations are in msecs and
deadlines are in jiffies.  ata_deadline() is added to compute deadline
from a start time and duration in msecs.

While at it, drop now superflous _msec suffix from arguments and
rename @timeout to @deadline if it represents a fixed point in time
rather than duration.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Improve SFF HSM violation reporting such that each HSM violation can
be distinguished using ehi_desc.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Fix G5 SATA irq 18: nobody cared, reported on -rc5 by Olaf Hering:
fixlet to a57c1bad libata-sff:
Fix oops reported in kerneloops.org for pnp devices with no ctl
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Tested-by: NOlaf Hering <olaf@aepfle.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- Make ata_sff_altstatus private so nobody uses it by mistake
- Drop the 400nS delay from it

Add

ata_sff_irq_status	-	encapsulates the IRQ check logic

This function keeps the existing behaviour for altstatus using devices. I
actually suspect the logic was wrong before the changes but -rc isn't the
time to play with that

ata_sff_sync		-	ensure writes hit the device

Really we want an io* operation for 'is posted' eg ioisposted(ioaddr) so
that we can fix the nasty delay this causes on most systems.

- ata_sff_pause		-	400nS delay

Ensure the command hit the device and delay 400nS

- ata_sff_dma_pause

Ensure the I/O hit the device and enforce an HDMA1:0 transition delay.
Requires altstatus register exists, BUG if not so we don't risk
corruption in MWDMA modes. (UDMA the checksum will save your backside in
theory)

The only other complication then is devices with their own handlers.
rb532 can use dma_pause but scc needs to access its own altstatus
register for internal errata workarounds so directly call the drivers own
altstatus function.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Some controllers (jmb and inic162x) use 0x77 and 0x7f to indicate that
the device isn't ready yet.  It looks like they use 0xff if device
presence is detected but connection isn't established.  0x77 or 0x7f
after connection is established and use the value from signature FIS
after receiving it.

This patch implements ata_check_ready(), which takes TF status value
and determines whether the port is ready or not considering the above
and other conditions, and use it in @check_ready() functions.  This is
safe as both 0x77 and 0x7f aren't valid ready status value even though
they have BSY bit cleared.

This fixes hot plug detection failures which can be triggered with
certain drives if they aren't already spun up when the data connector
is hot plugged.

Tested on sil, sil24, ahci (jmb/ich), piix and inic162x combined with
eight drives from all major vendors.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

WARN_ON()'s in ata_hsm_move() was too liberal and got triggerred when
it shouldn't (e.g. hotplug events at the right moment).  As the HSM
only deals with device errors and state machine violations, make it
check only against them.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Mark Lord <liml@rtr.ca>
Cc: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Currently, SATA softresets should do link onlineness check before
actually performing SRST protocol but it doesn't really belong to
softreset.

This patch moves onlineness check in softreset to ata_eh_reset() and
ata_eh_followup_srst_needed() to clean up code and help future sata_mv
changes which need clear separation between SCR and TF accesses.

sata_fsl is peculiar in that its softreset really isn't softreset but
combination of hardreset and softreset.  This patch adds dummy private
->prereset to keep the current behavior but the driver really should
implement separate hard and soft resets and return -EAGAIN from
hardreset if it should be follwed by softreset.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>