Commit Graph

550 Commits

Author SHA1 Message Date
Adam Buchbinder
c9404c9c39 Fix misspelling of "should" and "shouldn't" in comments.
Some comments misspell "should" or "shouldn't"; this fixes them. No code changes.

Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-05 12:22:30 +01:00
Tejun Heo
5040ab67a2 libata: retry link resume if necessary
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: Tejun Heo <tj@kernel.org>
Reported-by: fengxiangjun <fengxiangjun@neusoft.com>
Reported-by: Jim Faulkner <jfaulkne@ccs.neu.edu>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-01-12 14:34:14 -05:00
Bartlomiej Zolnierkiewicz
9cd13bdbae libata: add comment documenting PIO latency issues on UP
Based on:
http://lkml.indiana.edu/hypermail/linux/kernel/0908.2/01420.html

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-12-03 14:36:16 -05:00
Julia Lawall
a1104016ce drivers/ata/libata: Move dereference after NULL test
In each case, if the NULL test on qc is needed, then the derefernce
should be after the NULL test.

A simplified version of the semantic match that detects this problem is as
follows (http://coccinelle.lip6.fr/):

// <smpl>
@match exists@
expression x, E;
identifier fld;
@@

* x->fld
  ... when != \(x = E\|&x\)
* x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-11-03 14:26:12 -05:00
Tejun Heo
f4b31db92d libata: fix internal command failure handling
When an internal command fails, it should be failed directly without
invoking EH.  In the original implemetation, this was accomplished by
letting internal command bypass failure handling in ata_qc_complete().
However, later changes added post-successful-completion handling to
that code path and the success path is no longer adequate as internal
command failure path.  One of the visible problems is that internal
command failure due to timeout or other freeze conditions would
spuriously trigger WARN_ON_ONCE() in the success path.

This patch updates failure path such that internal command failure
handling is contained there.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-10-16 06:22:31 -04:00
Tejun Heo
110f66d25c 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>
2009-10-06 00:26:27 -04:00
Tejun Heo
4dc738ed2a libata: fix spurious WARN_ON_ONCE() on port freeze
Commit 54c38444fa makes libata abort qcs
after the port is frozen.  This is necessary to guarantee that TF
registers are accessed after the DMA engine is shutdown after an
error.  However, this triggers WARN_ON_ONCE() check in
ata_qc_complete() spuriously.  Move WARN_ON_ONCE() downwards such that
failing commands while frozen doesn't trigger it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-09-17 16:45:40 -04:00
Tejun Heo
ac8672ea92 libata: fix off-by-one error in ata_tf_read_block()
ata_tf_read_block() has off-by-one error when converting CHS address
to LBA.  The bug isn't very visible because ata_tf_read_block() is
used only when generating sense data for a failed RW command and CHS
addressing isn't used too often these days.

This problem was spotted by Atsushi Nemoto.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-09-08 21:18:03 -04:00
Shaohua Li
388539f3ff [libata] add DMA setup FIS auto-activate feature
Hopefully results in fewer on-the-wire FIS's and no breakage.  We'll see!

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-09-01 19:47:19 -04:00
Tejun Heo
7831387bda libata: OCZ Vertex can't do HPA
OCZ Vertex SSD can't do HPA and not in a usual way.  It reports HPA,
allows unlocking but then fails all IOs which fall in the unlocked
area.  Quirk it so that HPA unlocking is not used for the device.

Reported by Daniel Perup in bnc#522414.

 https://bugzilla.novell.com/show_bug.cgi?id=522414

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Daniel Perup <probe@spray.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12 06:17:33 -04:00
Tejun Heo
5920dadfb4 libata: accept late unlocking of HPA
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: Tejun Heo <tj@kernel.org>
Reported-by: Christof Warlich <christof@warlich.name>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-07-28 21:07:09 -04:00
Tejun Heo
d0cb43b35d libata: implement and use HORKAGE_NOSETXFER, take#2
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: Tejun Heo <tj@kernel.org>
Reported-by: Moritz Rigler <linux-ide@momail.e4ward.com>
Reported-by: Lars <lars21ce@gmx.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-07-14 22:41:46 -04:00
Tejun Heo
0d9e6659a1 libata: don't set IORDY for reset
Before issuing reset, libata configures xfermode to PIO0 which makes
some drivers turn on IORDY which may cause the controller to lock up
if the port is not occupied.  IORDY isn't necessary at this point
anyway.  Make ata_pio_need_iordy() return zero if it's being called
for reset.

This fixes bko#11703.  Reported and tracked down by Daniel Gnoutcheff
and Constantine Gavrilov.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Daniel Gnoutcheff <gnoutchd@union.edu>
Cc: Constantine Gavrilov <constantine.gavrilov@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-06-23 01:54:30 -04:00
Evgeni Golov
ad5d8eac91 [libata] beautify module parameters
1. add defaults to description where possible
2. add value definition (off=0, on=1) where missing

v2: reformatted as per request by Jeff Garzik <jgarzik@pobox.com>
    "Enable foo (0=off, 1=on [default])"

Signed-off-by: Evgeni Golov <sargentd@die-welt.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-06-23 01:53:58 -04:00
Jens Axboe
437681800b [libata] get rid of ATA_MAX_QUEUE loop in ata_qc_complete_multiple() v2
We very rarely (if ever) complete more than one command in the
sactive mask at the time, even for extremely high IO rates. So
looping over the entire range of possible tags is pointless,
instead use __ffs() to just find the completed tags directly.

Updated to clear the tag from the done_mask instead of shifting
done_mask down as suggested by From: Tejun Heo <htejun@gmail.com>
Verified with a user space tester to produce the same results.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-06-10 07:50:17 -04:00
Borislav Petkov
f0d0613ded libata: fix suspend/resume for ATA SEMB devices
79b42babba fixed identifying ATA devices
reporting 3c/c3 signature which belongs to SEMB devices now. However,
suspending the machine with such device (WDC WD2500AAJS-6 01.0) fails
with the following:

hda: host max PIO4 wanted PIO255(auto-tune) selected PIO4
hda: UDMA/100 mode selected
hdb: host max PIO4 wanted PIO255(auto-tune) selected PIO4
hdb: UDMA/66 mode selected
sd 1:0:0:0: [sda] Starting disk
ata5: SATA link down (SStatus 0 SControl 300)
ata1: SATA link down (SStatus 0 SControl 300)
ata3: SATA link down (SStatus 0 SControl 300)
ata6: SATA link down (SStatus 0 SControl 300)
ata2: softreset failed (device not ready)
ata2: failed due to HW bug, retry pmp=0
ata4: softreset failed (device not ready)
ata4: failed due to HW bug, retry pmp=0
ata4: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata2.00: class mismatch 1 != 7
ata2.00: revalidation failed (errno=-19)
ata2: limiting SATA link speed to 1.5 Gbps
ata4.00: configured for UDMA/133
ata2: softreset failed (device not ready)
ata2: failed due to HW bug, retry pmp=0
ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
ata2.00: class mismatch 1 != 7
ata2.00: revalidation failed (errno=-19)
ata2.00: disabled
sd 1:0:0:0: rejecting I/O to offline device
sd 1:0:0:0: [sda] START_STOP FAILED
sd 1:0:0:0: [sda] Result: hostbyte=0x01 driverbyte=0x00
PM: Device 1:0:0:0 failed to thaw: error 65536
sd 3:0:0:0: [sdb] Starting disk

due to a class mismatch in ata_dev_revalidate(). Fix it by adding the
ATA_DEV_SEMB device class to the check.

CC: Tejun Heo <htejun@gmail.com>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-05-11 14:31:10 -04:00
Sergei Shtylyov
62afe5d744 libata: use ATA_ID_CFA_*
Use ATA_ID_CFA_* constants for CFA specific identify data words 162 and 163.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-04-16 15:22:18 -04:00
Tejun Heo
79b42babba libata: handle SEMB signature better
WDC WD1600JS-62MHB5 successfully hits the window between ATA/ATAPI-7
and Serial ATA II standards and reports 3c/c3 signature which now is
assigned to SEMB.  Make ata_dev_classify() report ATA_DEV_SEMB on the
sig and let ata_dev_read_id() work around it by trying IDENTIFY once.

This fixes bko#11579.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: David Haun <drhaun88@gmail.com>
Reported-by: Lars Wirzenius <liw@liw.fi>
Reported-by: Juan Manuel <jmcarranza@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-04-16 15:21:00 -04:00
Vegard Nossum
f6005354d6 ata: fix obviously wrong comment
Also remove the now-useless debug printouts which are supposed to
tell us when the scan starts and ends.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-04-13 04:22:04 -04:00
Mark Lord
e18086d69c [libata] More robust parsing for IDENTIFY DEVICE multi_count field
Make libata more robust when parsing the multi_count
field from a drive's identify data.  This prevents us from
attempting to use dubious multi_count values ad infinitum.

Reset dev->multi_count to zero and reprobe it each time
through this routine, as it can change on device reset.

Also ensure that the reported "maximum" value is valid
and is a power of two, and that the reported "count" value
is valid and also a power of two.  And that the "count"
value is not greater than the "maximum" value.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-03-24 22:40:05 -04:00
Mark Lord
1a660164c2 [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>
2009-03-24 22:02:41 -04:00
Robert Hancock
968e594afd libata: Don't trust current capacity values in identify words 57-58
Hanno Böck reported a problem where an old Conner CP30254 240MB hard drive
was reported as 1.1TB in capacity by libata:

http://lkml.org/lkml/2009/2/13/134

This was caused by libata trusting the drive's reported current capacity in
sectors in identify words 57 and 58 if the drive does not support LBA and the
current CHS translation values appear valid. Unfortunately it seems older
ATA specs were vague about what this field should contain and a number of drives
used values with wrong byte order or that were totally bogus. There's no
unique information that it conveys and so we can just calculate the number
of sectors from the reported current CHS values.

While we're at it, clean up this function to use named constants for the
identify word values.

Signed-off-by: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-03-05 07:26:10 -05:00
FUJITA Tomonori
5825627c94 libata: fix dma_unmap_sg misuse
libata passes the returned value of dma_map_sg() to
dma_unmap_sg(),which is the misuse of dma_unmap_sg().

DMA-mapping.txt says:

To unmap a scatterlist, just call:

	pci_unmap_sg(pdev, sglist, nents, direction);

Again, make sure DMA activity has already finished.

PLEASE NOTE:  The 'nents' argument to the pci_unmap_sg call must be
              the _same_ one you passed into the pci_map_sg call,
	      it should _NOT_ be the 'count' value _returned_ from the
              pci_map_sg call.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-03-05 07:24:57 -05:00
Tejun Heo
9062712fa9 libata: implement HORKAGE_1_5_GBPS and apply it to WD My Book
3Gbps is often much more prone to transmission failures.  It's usually
okay to let EH handle speed down after transmission failures but some
WD My Book drives completely shutdown after certain transmission
failures and after it only power cycling can revive them.  Combined
with the fact that external drives often end up with cable assembly
which is longer than usual and more likely to have intervening gender,
this makes these drives very likely to shutdown under certain
configurations virtually rendering them unusable.

This patch implements HOARKGE_1_5_GBPS and applies it to WD My Book
such that 1.5Gbps is forced once the device is identified.

Please take a look at the following bz for related reports.

  http://bugzilla.kernel.org/show_bug.cgi?id=9913

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-02-02 23:04:31 -05:00
Tejun Heo
a07d499b47 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>
2009-02-02 23:03:22 -05:00
Tejun Heo
99cf610aa4 libata: clear dev->ering in smarter way
dev->ering used to be cleared together with the rest of ata_device in
ata_dev_init() which is called whenever a probing event occurs.
dev->ering is about to be used to track probing failures so it needs
to remain persistent over multiple porbing events.  This patch
achieves this by doing the following.

* Instead of CLEAR_OFFSET, define CLEAR_BEGIN and CLEAR_END and only
  clear between BEGIN and END.  ering is moved after END.  The split
  of persistent area is to allow hotter items remain at the head.

* ering is explicitly cleared on ata_dev_disable() and when device
  attach succeeds.  So, ering is persistent throug a device's life
  time (unless explicitly cleared of course) and also through periods
  inbetween disablement of an attached device and successful detection
  of the next one.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-02-02 23:03:17 -05:00
Tejun Heo
9913ff8abf libata: check onlineness before using SPD in sata_down_spd_limit()
sata_down_spd_limit() should check whether the link is online before
using the SPD value to determine how to limit the link speed.  Factor
out onlineness test and test it from sata_down_spd_limit().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-02-02 23:03:08 -05:00
Tejun Heo
678afac678 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>
2009-02-02 23:03:00 -05:00
Randy Dunlap
5eb66fe05f libata: fix kernel-doc warnings
Fix libata kernel-doc warnings:

Warning(linux-next-20090120//drivers/ata/libata-core.c:4720): Excess function parameter 'dev' description in 'ata_qc_new'
Warning(linux-next-20090120//drivers/ata/libata-scsi.c:428): No description found for parameter 'ap'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-02-02 22:41:45 -05:00
David Daney
3ada9c1264 libata: Add another column to the ata_timing table.
The forthcoming OCTEON SOC Compact Flash driver needs an additional
timing value that was not available in the ata_timing table.  I add a
new column for dmack_hold time.  The values were obtained from the
Compact Flash specification Rev 4.1.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-01-16 10:23:37 -05:00
Jeff Garzik
94be9a58d7 [libata] get-identity ioctl: Fix use of invalid memory pointer
for SAS drivers.

Caught by Ke Wei (and team?) at Marvell.

Also, move the ata_scsi_ioctl export to libata-scsi.c, as that seems to be the
general trend.

Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-01-16 10:17:09 -05:00
Arjan van de Ven
fa853a4841 libata: only ports >= 0 need to synchronize
In a discussio with Jeff Garzik, he mentioned that the serialization
for the libata port probes only needs to be within the domain of a host.
This means that for the first port of each host (with ID 0), we don't
need to wait, so we can relax our serialization a little.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-10 15:06:52 -08:00
Arjan van de Ven
886ad09fc8 libata: Add a per-host flag to opt-in into parallel port probes
This patch adds a per host flag that allows drivers to opt in into
having its busses scanned in parallel.

Drivers that do not set this flag get their ports scanned in
the "original" sequence.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-10 15:06:52 -08:00
Tejun Heo
efcb3cf7f0 libata: use WARN_ON_ONCE on hot paths
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: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-09 11:54:22 -08:00
David Daney
5c18c4d28b libata: Add special ata_pio_need_iordy() handling for Compact Flash.
According to the Compact Flash specification r4.1, PIO modes 5 and 6
do not use iordy.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-01-08 16:10:36 -05:00
Shane Huang
8522ee25f3 [libata] ahci: Add SATA GEN3 related messages
The present AHCI driver seems to support SATA GEN 3 speed, but the related
messages should be modified.

Signed-off-by: Shane Huang <shane.huang@amd.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-01-08 16:09:57 -05:00
Arjan van de Ven
f29d3b2323 fastboot: Make libata initialization even more async
As suggested by Linus: Don't do the libata init in 2 separate
steps with a global sync inbetween, but do it as one async step,
with a local sync before registering the device.

This cuts the boottime on my machine with 2 sata controllers down
significantly, and it seems to work. Would be nice if the libata
folks take a good look at this patch though..

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2009-01-07 08:47:11 -08:00
Arjan van de Ven
793180570f fastboot: make the libata port scan asynchronous
This patch makes the libata port scanning asynchronous (per device).
There is a synchronization point before doing the actual disk scan
so that device ordering is not affected.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2009-01-07 08:46:57 -08:00
Lubomir Bulej
5ccfca974f libata: blacklist NCQ on OCZ CORE 2 SSD (resend)
The patchlet below blacklists NCQ on OCZ CORE v2 SSD drive(s). Even
though the drive advertises NCQ support with queue depth 1, it responds
with all-zeroes FIS to NCQ commands which triggers ata error handling
several times before the kernel decides to disable NCQ on the drive.

Signed-off-by: Lubomir Bulej <lubomir.bulej@dsrg.mff.cuni.cz>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-29 07:39:25 -05:00
Qinghuang Feng
bd353ffdc9 [libata] Update kernel-doc comments to match source code
Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
2008-12-28 22:43:21 -05:00
Tejun Heo
ece180d1cf libata: perform port detach in EH
ata_port_detach() first made sure EH saw ATA_PFLAG_UNLOADING and then
assumed EH context belongs to it and performed detach operation
itself.  However, UNLOADING doesn't disable all of EH and this could
lead to problems including triggering WARN_ON()'s in EH path.

This patch makes port detach behave more like other EH actions such
that ata_port_detach() requests EH to detach and waits for completion.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-28 22:43:21 -05:00
Tejun Heo
ad74e4c18d libata: when restoring SControl during detach do the PMP links first
When restoring SControl during detach, PMP links should be handled
first as changing SControl of the host link can affect SCR access of
PMP links.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-28 22:43:21 -05:00
Tejun Heo
1eca4365be libata: beef up iterators
There currently are the following looping constructs.

* __ata_port_for_each_link() for all available links
* ata_port_for_each_link() for edge links
* ata_link_for_each_dev() for all devices
* ata_link_for_each_dev_reverse() for all devices in reverse order

Now there's a need for looping construct which is similar to
__ata_port_for_each_link() but iterates over PMP links before the host
link.  Instead of adding another one with long name, do the following
cleanup.

* Implement and export ata_link_next() and ata_dev_next() which take
  @mode parameter and can be used to build custom loop.
* Implement ata_for_each_link() and ata_for_each_dev() which take
  looping mode explicitly.

The following iteration modes are implemented.

* ATA_LITER_EDGE		: loop over edge links
* ATA_LITER_HOST_FIRST		: loop over all links, host link first
* ATA_LITER_PMP_FIRST		: loop over all links, PMP links first

* ATA_DITER_ENABLED		: loop over enabled devices
* ATA_DITER_ENABLED_REVERSE	: loop over enabled devices in reverse order
* ATA_DITER_ALL			: loop over all devices
* ATA_DITER_ALL_REVERSE		: loop over all devices in reverse order

This change removes exlicit device enabledness checks from many loops
and makes it clear which ones are iterated over in which direction.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-28 22:43:20 -05:00
Tejun Heo
d10d491f84 libata: fix Seagate NCQ+FLUSH blacklist
Due to miscommunication, P/N was mistaken as firmware revision
strings.  Update it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-16 05:40:30 -05:00
Tejun Heo
ac70a964b0 libata: blacklist Seagate drives which time out FLUSH_CACHE when used with NCQ
Some recent Seagate harddrives have firmware bug which causes FLUSH
CACHE to timeout under certain circumstances if NCQ is being used.
This can be worked around by disabling NCQ and fixed by updating the
firmware.  Implement ATA_HORKAGE_FIRMWARE_UPDATE and blacklist these
devices.

The wiki page has been updated to contain information on this issue.

  http://ata.wiki.kernel.org/index.php/Known_issues

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-12-01 13:49:27 -05:00
Roland Dreier
44901a9684 libata: Avoid overflow in ata_tf_read_block() when tf->hba_lbal > 127
Phillip O'Donnell <phillip.odonnell@gmail.com> pointed out that the same
sign extension bug that was fixed in commit ba14a9c2 ("libata: Avoid
overflow in ata_tf_to_lba48() when tf->hba_lbal > 127") also appears to
exist in ata_tf_read_block().  Fix this by adding a cast to u64.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-11-11 02:59:27 -05:00
Tejun Heo
8a8bc22332 libata: revert convert-to-block-tagging patches
This patch reverts the following three commits which convert libata to
use block layer tagging.

 43a49cbdf3
 e013e13bf6
 2fca5ccf97

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>
2008-11-10 08:04:47 -08:00
Tejun Heo
299246f9a2 libata: mask off DET when restoring SControl for detach
libata restores SControl on detach; however, trying to restore
non-zero DET can cause undeterministic behavior including PMP device
going offline till power cycling.  Mask off DET when restoring
SControl.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-11-04 01:08:33 -05:00
Tejun Heo
6a87e42e95 libata: implement ATA_HORKAGE_ATAPI_MOD16_DMA and apply it
libata always uses PIO for ATAPI commands when the number of bytes to
transfer isn't multiple of 16 but quantum DAT72 chokes on odd bytes
PIO transfers.  Implement a horkage to skip the mod16 check and apply
it to the quantum device.

This is reported by John Clark in the following thread.

  http://thread.gmane.org/gmane.linux.ide/34748

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: John Clark <clarkjc@runbox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-11-04 01:08:27 -05:00
Jens Axboe
9ce8e3073d libata: add whitelist for devices with known good pata-sata bridges
libata currently imposes a UDMA5 max transfer rate and 200 sector max
transfer size for SATA devices that sit behind a pata-sata bridge. Lots
of devices have known good bridges that don't need this limit applied.
The MTRON SSD disks are such devices. Transfer rates are increased by
20-30% with the restriction removed.

So add a "blacklist" entry for the MTRON devices, with a flag indicating
that the bridge is known good.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-31 01:45:06 -04:00
Roland Dreier
ba14a9c291 libata: Avoid overflow in ata_tf_to_lba48() when tf->hba_lbal > 127
In ata_tf_to_lba48(), when evaluating

	(tf->hob_lbal & 0xff) << 24

the expression is promoted to signed int (since int can hold all values
of u8).  However, if hob_lbal is 128 or more, then it is treated as a
negative signed value and sign-extended when promoted to u64 to | into
sectors, which leads to the MSB 32 bits of section getting set
incorrectly.

For example, Phillip O'Donnell <phillip.odonnell@gmail.com> reported
that a 1.5GB drive caused:

    ata3.00: HPA detected: current 2930277168, native 18446744072344861488

where 2930277168 == 0xAEA87B30 and 18446744072344861488 == 0xffffffffaea87b30
which shows the problem when hob_lbal is 0xae.

Fix this by adding a cast to u64, just as is used by for hob_lbah and
hob_lbam in the function.

Reported-by: Phillip O'Donnell <phillip.odonnell@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-31 01:42:59 -04:00
Randy Dunlap
5b97fbd093 ATA: remove excess kernel-doc notation
Remove excess kernel-doc function parameter notation from drivers/ata/:

Warning(drivers/ata/libata-core.c:1622): Excess function parameter or struct member 'fn' description in 'ata_pio_queue_task'
Warning(drivers/ata/libata-core.c:4655): Excess function parameter or struct member 'err_mask' description in 'ata_qc_complete'
Warning(drivers/ata/ata_piix.c:751): Excess function parameter or struct member 'udma' description in 'do_pata_set_dmamode'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-31 01:42:49 -04:00
Randy Dunlap
3cd8ddbd86 libata: add missing kernel-doc
Fix libata missing kernel-doc:

Warning(lin2628-rc2//drivers/ata/libata-core.c:4562): No description
found for parameter 'tag'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-27 23:55:23 -04:00
Tejun Heo
4a9c7b3359 libata: fix device iteration bugs
There were several places where only enabled devices should be
iterated over but device enabledness wasn't checked.

* IDENTIFY data 40 wire check in cable_is_40wire()
* xfer_mode/ncq_enabled saving in ata_scsi_error()
* DUBIOUS_XFER handling in ata_set_mode()

While at it, reformat comments in cable_is_40wire().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-27 23:55:12 -04:00
Jens Axboe
2fca5ccf97 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>
2008-10-23 16:05:26 -07:00
Tejun Heo
f667fdbbbe libata: initialize port_task when !CONFIG_ATA_SFF
ap->port_task was not initialized if !CONFIG_ATA_SFF later triggering
lockdep warning.  Make sure it's initialized.

Reported by Larry Finger.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-10-22 20:40:01 -04:00
Elias Oltmanns
45fabbb77b libata: Implement disk shock protection support
On user request (through sysfs), the IDLE IMMEDIATE command with UNLOAD
FEATURE as specified in ATA-7 is issued to the device and processing of
the request queue is stopped thereafter until the specified timeout
expires or user space asks to resume normal operation. This is supposed
to prevent the heads of a hard drive from accidentally crashing onto the
platter when a heavy shock is anticipated (like a falling laptop
expected to hit the floor). In fact, the whole port stops processing
commands until the timeout has expired in order to avoid any resets due
to failed commands on another device.

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-09-29 00:27:54 -04:00
Tejun Heo
b1c72916ab 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>
2008-09-29 00:25:28 -04:00
Tejun Heo
b5b3fa386b libata: misc updates to prepare for slave link
* Add ATA_EH_ALL_ACTIONS.

* Make sata_link_{on|off}_line() return bool instead of int.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-09-29 00:22:32 -04:00
Tejun Heo
aadffb682c libata: reimplement link iterator
Implement __ata_port_next_link() and reimplement
__ata_port_for_each_link() and ata_port_for_each_link() using it.
This removes relatively large inlined code and makes iteration easier
to extend.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-09-29 00:22:30 -04:00
Tejun Heo
82ef04fb4c libata: make SCR access ops per-link
Logically, SCR access ops should take @link; however, there was no
compelling reason to convert all SCR access ops when adding @link
abstraction as there's one-to-one mapping between a port and a non-PMP
link.  However, that assumption won't hold anymore with the scheduled
addition of slave link.

Make SCR access ops per-link.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-09-29 00:22:28 -04:00
Alan Cox
b15b3ebae1 libata: Fix a large collection of DMA mode mismatches
Dave Müller sent a diff for the pata_oldpiix that highlighted a problem
where a lot of the ATA drivers assume dma_mode == 0 means "no DMA" while
the core code uses 0xFF.

This turns out to have other consequences such as code doing >= XFER_UDMA_0
also catching 0xFF as UDMAlots. Fortunately it doesn't generally affect
set_dma_mode, although some drivers call back into their own set mode code
from other points.

Having been through the drivers I've added helpers for using_udma/using_mwdma
dma_enabled so that people don't open code ranges that may change (eg if UDMA8
appears somewhere)

Thanks to David for the initial bits
[and added fix for pata_oldpiix from and signed-off-by Dave Mueller
 <dave.mueller@gmx.ch>  -jg]

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-08-22 02:27:49 -04:00
Tejun Heo
d127ea7b86 libata: restore SControl on detach
Save SControl during probing and restore it on detach.  This prevents
adjustments made by libata drivers to seep into the next driver which
gets attached (be it a libata one or not).

It's not clear whether SControl also needs to be restored on suspend.
The next system to have control (ACPI or kexec'd kernel) would
probably like to see the original SControl value but there's no
guarantee that a link is gonna keep working after SControl is adjusted
without a reset and adding a reset and modified recovery cycle soley
for this is an overkill.  For now, do it only for detach.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-08-22 02:19:46 -04:00
Tejun Heo
05944bdf6f libata: implement no[hs]rst force params
Implement force params nohrst, nosrst and norst.  This is to work
around reset related problems and ease debugging.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-08-22 02:07:43 -04:00
Alan Cox
963e4975c6 pata_it821x: Driver updates and reworking
- Add support for the RDC 1010 variant
- Rework the core library to have a read_id method. This allows the hacky
  bits of it821x to go and prepares us for pata_hd
- Switch from WARN to BUG in ata_id_string as it will reboot if you get
  it wrong so WARN won't be seen
- Allow the issue of command 0xFC on the 821x. This is needed to query
  rebuild status.
- Tidy up printk formatting
- Do more ident rewriting on RAID volumes to handle firmware provided
  ident data which is rather wonky
- Report the firmware revision and device layout in RAID mode
- Don't try and disable raid on the 8211 or RDC - they don't have the
  relevant bits

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-07-31 02:04:50 -04:00
Elias Oltmanns
49ea3b0497 libata-core: make sure that ata_force_tbl is freed in case of an error
Fix a potential memory leak when ata_init() encounters an error.

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-07-31 01:47:12 -04:00
Tejun Heo
2486fa561a 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>
2008-07-31 01:47:05 -04:00
Tejun Heo
87fbc5a060 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>
2008-07-14 15:59:32 -04:00
Tejun Heo
341c2c958e libata: consistently use msecs for time durations
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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-07-14 15:59:32 -04:00
Tejun Heo
5895ef9a5b 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>
2008-06-18 20:27:49 -04:00
Pradeep Singh Rautela
2da676594a ata: Convert to static DEFINE_SPINLOCK(lock)
Replace deprecated static spinlock_t instance to static DEFINE_SPINLOCK(lock).

Signed-off-by: Pradeep Singh <rautelap@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-30 12:37:43 -04:00
Tejun Heo
50af2fa1e1 libata: ignore SIMG4726 config pseudo device
I was hoping ATA_HORKAGE_NODMA | ATA_HORKAGE_SKIP_PM could keep it
happy but no even this doesn't work under certain configurations and
it's not like we can do anything useful with the cofig device anyway.
Replace ATA_HORKAGE_SKIP_PM with ATA_HORKAGE_DISABLE and use it for
the config device.  This makes the device completely ignored by
libata.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19 17:51:48 -04:00
Tejun Heo
391191c116 libata: don't schedule LPM action seperately during probing
There's no reason to schedule LPM action after probing is complete
causing another EH iteration.  Just schedule it together with probing
itself.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19 17:51:48 -04:00
Tejun Heo
f046519fc8 libata: kill hotplug related race condition
Originally, whole reset processing was done while the port is frozen
and SError was cleared during @postreset().  This had two race
conditions.  1: hotplug could occur after reset but before SError is
cleared and libata won't know about it.  2: hotplug could occur after
all the reset is complete but before the port is thawed.  As all
events are cleared on thaw, the hotplug event would be lost.

Commit ac371987a8 kills the first race
by clearing SError during link resume but before link onlineness test.
However, this doesn't fix race #2 and in some cases clearing SError
after SRST is a good idea.

This patch solves this problem by cross checking link onlineness with
classification result after SError is cleared and port is thawed.
Reset is retried if link is online but all devices attached to the
link are unknown.  As all devices will be revalidated, this one-way
check is enough to ensure that all devices are detected and
revalidated reliably.

This, luckily, also fixes the cases where host controller returns
bogus status while harddrive is spinning up after hotplug making
classification run before the device sends the first FIS and thus
causes misdetection.

Low level drivers can bypass the logic by setting class explicitly to
ATA_DEV_NONE if ever necessary (currently none requires this).

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19 17:51:47 -04:00
Tejun Heo
0cbf0711a1 libata: fix sata_link_hardreset() @online out parameter handling
The @online out parameter is supposed to set to true iff link is
online and reset succeeded as advertised in the function description
and callers are coded expecting that.  However, sata_link_reset()
didn't behave this way on device readiness test failure.  Fix it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19 17:51:47 -04:00
Mark Lord
10acf3b0d3 libata: export ata_eh_analyze_ncq_error
Export ata_eh_analyze_ncq_error() for subsequent use by sata_mv,
as suggested by Tejun.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-06 11:37:58 -04:00
Alan Cox
a79067e513 libata: More TSSTcorp pain, keep in sync with legacy IDE
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-29 17:41:13 -04:00
Adrian Bunk
1dc55e8761 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>
2008-04-25 00:46:11 -04:00
Adrian Bunk
6bdb4fc9f9 make sata_print_link_status() static
sata_print_link_status() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-25 00:46:09 -04:00
Harvey Harrison
2b4221bb54 libata: functions with definition should not be extern
Noticed by sparse
drivers/ata/libata-core.c:3380:12: warning: function 'ata_wait_after_reset' with external linkage has definition

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-24 23:42:26 -04:00
Matthew Wilcox
d3135846f6 drivers: Remove unnecessary inclusions of asm/semaphore.h
None of these files use any of the functionality promised by
asm/semaphore.h.  It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18 22:16:32 -04:00
Alan Cox
b93fda1235 libata: Be a bit more slack about early devices
We have a certain number of 'ATA' emulations often on CF or other flash
devices that are at best "loosely based" on the CF 1.1 standard. These
devices report themselves as disk but don't support the ATA minimal
command set only the CF 1.1 set.

Relax the PIO checking for devices reporting ATA rev 0, or no iordy
support, or CFA. Rework the code a bit as it was already messy and this
made it quite ugly.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-17 15:44:25 -04:00
Alan Cox
f792068e43 libata: cable logic
The cable detect isolation patch inadvertently removed 40 wire short
cable handling. Put it back

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-17 15:44:25 -04:00
Tejun Heo
45db2f6c95 libata: move link onlineness check out of softreset methods
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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-17 15:44:25 -04:00
Tejun Heo
071f44b1d2 libata: implement PMP helpers
Implement helpers to test whether PMP is supported, attached and
determine pmp number to use when issuing SRST to a link.  While at it,
move ata_is_host_link() so that it's together with the two new PMP
helpers.

This change simplifies LLDs and helps making PMP support optional.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:25 -04:00
Tejun Heo
48515f6c00 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>
2008-04-17 15:44:25 -04:00
Tejun Heo
127102aea2 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>
2008-04-17 15:44:24 -04:00
Tejun Heo
182d7bbac3 libata: clean up dummy port_ops
Now that SFF assumptions are removed from core layer, dummy port_ops
can be slimmed down.  Chop it down.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:24 -04:00
Tejun Heo
c9f75b04ed libata: kill ata_noop_dev_select()
Now that SFF assumptions are separated out from non-SFF reset
sequence, port_ops->sff_dev_select() is no longer necessary for
non-SFF controllers.  Kill ata_noop_dev_select() and ->sff_dev_select
initialization from base and other non-SFF port_ops.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:24 -04:00
Tejun Heo
4c9bf4e799 libata: replace tf_read with qc_fill_rtf for non-SFF drivers
Now that all SFF stuff is separated out of core layer, core layer
doesn't call ops->tf_read directly.  It gets called only via
ops->qc_fill_rtf() for non-SFF drivers.  This patch directly
implements private ops->qc_fill_rtf() for non-SFF controllers and kill
ops->tf_read().

This is much cleaner for non-SFF controllers as some of them have to
cache SFF register values in private data structure and report the
cached values via ops->tf_read().  Also, ops->tf_read() gets nasty for
controllers which don't have clear notion of TF registers when
operation is not in progress.

As this change makes default ops->qc_fill_rtf unnecessary, move
ata_sff_qc_fill_rtf() form ata_base_port_ops to ata_sff_port_ops where
it belongs.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
79f97dadfe libata: drop @finish_qc from ata_qc_complete_multiple()
ata_qc_complete_multiple() took @finish_qc and called it on every qc
before completing it.  This was to give opportunity to update TF cache
before ata_qc_complete() tries to fill result_tf.  Now that result TF
is a separate operation, this is no longer necessary.

Update sata_sil24, which was the only user of this mechanism, such
that it implements its own ops->qc_fill_rtf() and drop @finish_qc from
ata_qc_complete_multiple().

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
22183bf569 libata: add qc_fill_rtf port operation
On command completion, ata_qc_complete() directly called ops->tf_read
to fill qc->result_tf.  This patch adds ops->qc_fill_rtf to replace
hardcoded ops->tf_read usage.

ata_sff_qc_fill_rtf() which uses ops->tf_read to fill result_tf is
implemented and set in ata_base_port_ops and other ops tables which
don't inherit from ata_base_port_ops, so this patch doesn't introduce
any behavior change.

ops->qc_fill_rtf() is similar to ops->sff_tf_read() but can only be
called when a command finishes.  As some non-SFF controllers don't
have TF registers defined unless they're associated with in-flight
commands, this limited operation makes life easier for those drivers
and help lifting SFF assumptions from libata core layer.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
305d2a1ab1 libata: unify mechanism to request follow-up SRST
Previously, there were two ways to trigger follow-up SRST from
hardreset method - returning -EAGAIN and leaving all device classes
unmodified.  Drivers never used the latter mechanism and the only use
case for the former was when hardreset couldn't classify.

Drop the latter mechanism and let -EAGAIN mean "perform follow-up SRST
if classification is required".  This change removes unnecessary
follow-up SRSTs and simplifies reset implementations.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
5958e3025f libata: move PMP SCR access failure during reset to ata_eh_reset()
If PMP fan-out reset fails and SCR isn't accessible, PMP should be
reset.  This used to be tested by sata_pmp_std_hardreset() and
communicated to EH by -ERESTART.  However, this logic is generic and
doesn't really have much to do with specific hardreset implementation.

This patch moves SCR access failure detection logic to ata_eh_reset()
where it belongs.  As this makes sata_pmp_std_hardreset() identical to
sata_std_hardreset(), the function is killed and replaced with the
standard method.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
ac371987a8 libata: clear SError after link resume
SError used to be cleared in ->postreset.  This has small hotplug race
condition.  If a device is plugged in after reset is complete but
postreset hasn't run yet, its hotplug event gets lost when SError is
cleared.  This patch makes sata_link_resume() clear SError.  This
kills the race condition and makes a lot of sense as some PMP and host
PHYs don't work properly without SError cleared.

This change makes sata_pmp_std_{pre|post}_reset()'s unnecessary as
they become identical to ata_std counterparts.  It also simplifies
sata_pmp_hardreset() and ahci_vt8251_hardreset().

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:23 -04:00
Tejun Heo
57c9efdfb3 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>
2008-04-17 15:44:23 -04:00
Tejun Heo
9dadd45b24 libata: move generic hardreset code from sata_sff_hardreset() to sata_link_hardreset()
sata_sff_hardreset() contains link readiness wait logic which isn't
SFF specific.  Move that part into sata_link_hardreset(), which now
takes two more parameters - @online and @check_ready.  Both are
optional.  The former is out parameter for link onlineness after
reset.  The latter is used to wait for link readiness after hardreset.

Users of sata_link_hardreset() is updated to use new funtionality and
ahci_hardreset() is updated to use sata_link_hardreset() instead of
sata_sff_hardreset().  This doesn't really cause any behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:22 -04:00
Tejun Heo
aa2731ad9a 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>
2008-04-17 15:44:22 -04:00
Tejun Heo
203c75b824 libata: separate out ata_std_postreset() from ata_sff_postreset()
Separate out generic ATA portion from ata_sff_postreset() into
ata_std_postreset() and implement ata_sff_postreset() using the std
version.

ata_base_port_ops now has ata_std_postreset() for its postreset and
ata_sff_port_ops overrides it to ata_sff_postreset().

This change affects pdc_adma, ahci, sata_fsl and sata_sil24.  pdc_adma
now specifies postreset to ata_sff_postreset() explicitly.  sata_fsl
and sata_sil24 now use ata_std_postreset() which makes no difference
to them.  ahci now calls ata_std_postreset() from its own postreset
method, which causes no behavior difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:22 -04:00
Tejun Heo
0aa1113d54 libata: separate out ata_std_prereset() from ata_sff_prereset()
Separate out generic ATA portion from ata_sff_prereset() into
ata_std_prereset() and implement ata_sff_prereset() using the std
version.  Waiting for device readiness is the only SFF specific part.

ata_base_port_ops now has ata_std_prereset() for its prereset and
ata_sff_port_ops overrides it to ata_sff_prereset().  This change can
affect pdc_adma, ahci, sata_fsl and sata_sil24.  pdc_adma implements
its own prereset using ata_sff_prereset() and the rest has hardreset
and thus are unaffected by this change.

This change reflects real world situation.  There is no generic way to
wait for device readiness for non-SFF controllers and some of them
don't have any mechanism for that.  Non-sff drivers which don't have
hardreset should wrap ata_std_prereset() and wait for device readiness
itself but there's no such driver now and isn't likely to be popular
in the future either.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:22 -04:00
Tejun Heo
288623a06c libata: clean up port_ops->sff_irq_clear()
->sff_irq_clear() is called only from SFF interrupt handler, so there
is no reason to initialize it for non-SFF controllers.  Also,
ata_sff_irq_clear() can handle both BMDMA and non-BMDMA SFF
controllers.

This patch kills ata_noop_irq_clear() and removes it from base
port_ops and sets ->sff_irq_clear to ata_sff_irq_clear() in sff
port_ops instead of bmdma port_ops.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:22 -04:00
Tejun Heo
5682ed33aa libata: rename SFF port ops
Add sff_ prefix to SFF specific port ops.

This rename is in preparation of separating SFF support out of libata
core layer.  This patch strictly renames ops and doesn't introduce any
behavior difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:22 -04:00
Tejun Heo
9363c3825e libata: rename SFF functions
SFF functions have confusing names.  Some have sff prefix, some have
bmdma, some std, some pci and some none.  Unify the naming by...

* SFF functions which are common to both BMDMA and non-BMDMA are
  prefixed with ata_sff_.

* SFF functions which are specific to BMDMA are prefixed with
  ata_bmdma_.

* SFF functions which are specific to PCI but apply to both BMDMA and
  non-BMDMA are prefixed with ata_pci_sff_.

* SFF functions which are specific to PCI and BMDMA are prefixed with
  ata_pci_bmdma_.

* Drop generic prefixes from LLD specific routines.  For example,
  bfin_std_dev_select -> bfin_dev_select.

The following renames are noteworthy.

  ata_qc_issue_prot() -> ata_sff_qc_issue()
  ata_pci_default_filter() -> ata_bmdma_mode_filter()
  ata_dev_try_classify() -> ata_sff_dev_classify()

This rename is in preparation of separating SFF support out of libata
core layer.  This patch strictly renames functions and doesn't
introduce any behavior difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:21 -04:00
Tejun Heo
d8b81b8008 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>
2008-04-17 15:44:20 -04:00
Tejun Heo
a5987e0a1b 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>
2008-04-17 15:44:20 -04:00
Alan Cox
15a5551c84 libata: isolate and rework cable logic
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-17 15:44:19 -04:00
Tejun Heo
3d5a3d67a5 libata: kill ata_chk_status() call from ata_dev_configure()
ata_dev_configure() isn't tied to any controller interface except for
the probe debug message printing at the end of the function.  Kill the
message.

This is to help separating out SFF support from core layer.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-17 15:44:18 -04:00
Tejun Heo
624d5c514e 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>
2008-04-17 15:44:18 -04:00
Tejun Heo
21572ea58a libata: drop ata_dev_select() from ata_dev_read_id
There is no reason to issue device select in read_id, it will be done
by ops->qc_issue() when IDENTIFY[_PACKET] is issued via
ata_exec_internal().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-17 15:44:18 -04:00
Tejun Heo
a1efdaba2d libata: make reset related methods proper port operations
Currently reset methods are not specified directly in the
ata_port_operations table.  If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods.  It's done this way for two reasons.

First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.

Second, as ->error_handler uses those reset methods, it can get
confusing.  ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.

Now that ops table uses inheritance, the first problem doesn't exist
anymore.  The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks.  In fact, there currently is no driver which actually
modifies error handling behavior.  Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH.  I don't think making ops layering strict has
any noticeable benefit.

This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops.  Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.

* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
  aren't accessible.  sata_promise doesn't need to use separate
  error_handlers for PATA and SATA anymore.

* softreset is broken for sata_inic162x and sata_sx4.  As libata now
  always prefers hardreset, this doesn't really matter but the ops are
  forced to NULL using ATA_OP_NULL for documentation purpose.

* pata_hpt374 needs to use different prereset for the first and second
  PCI functions.  This used to be done by branching from
  hpt374_error_handler().  The proper way to do this is to use
  separate ops and port_info tables for each function.  Converted.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:18 -04:00
Tejun Heo
887125e374 libata: stop overloading port_info->private_data
port_info->private_data is currently used for two purposes - to record
private data about the port_info or to specify host->private_data to
use when allocating ata_host.

This overloading is confusing and counter-intuitive in that
port_info->private_data becomes host->private_data instead of
port->private_data.  In addition, port_info and host don't correspond
to each other 1-to-1.  Currently, the first non-NULL
port_info->private_data is used.

This patch makes port_info->private_data just be what it is -
private_data for the port_info where LLD can jot down extra info.
libata no longer sets host->private_data to the first non-NULL
port_info->private_data, @host_priv argument is added to
ata_pci_init_one() instead.  LLDs which use ata_pci_init_one() can use
this argument to pass in pointer to host private data.  LLDs which
don't should use init-register model anyway and can initialize
host->private_data directly.

Adding @host_priv instead of using init-register model for LLDs which
use ata_pci_init_one() is suggested by Alan Cox.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
2008-04-17 15:44:17 -04:00
Tejun Heo
1bd5b715a3 libata: make ata_pci_init_one() not use ops->irq_handler and pi->sht
ata_pci_init_one() is the only function which uses ops->irq_handler
and pi->sht.  Other initialization functions take the same information
as arguments.  This causes confusion and duplicate unused entries in
structures.

Make ata_pci_init_one() take sht as an argument and use ata_interrupt
implicitly.  All current users use ata_interrupt and if different irq
handler is necessary open coding ata_pci_init_one() using
ata_prepare_sff_host() and ata_activate_sff_host can be done under ten
lines including error handling and driver which requires custom
interrupt handler is likely to require custom initialization anyway.

As ata_pci_init_one() was the last user of ops->irq_handler, this
patch also kills the field.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:17 -04:00
Tejun Heo
029cfd6b74 libata: implement and use ops inheritance
libata lets low level drivers build ata_port_operations table and
register it with libata core layer.  This allows low level drivers
high level of flexibility but also burdens them with lots of
boilerplate entries.

This becomes worse for drivers which support related similar
controllers which differ slightly.  They share most of the operations
except for a few.  However, the driver still needs to list all
operations for each variant.  This results in large number of
duplicate entries, which is not only inefficient but also error-prone
as it becomes very difficult to tell what the actual differences are.

This duplicate boilerplates all over the low level drivers also make
updating the core layer exteremely difficult and error-prone.  When
compounded with multi-branched development model, it ends up
accumulating inconsistencies over time.  Some of those inconsistencies
cause immediate problems and fixed.  Others just remain there dormant
making maintenance increasingly difficult.

To rectify the problem, this patch implements ata_port_operations
inheritance.  To allow LLDs to easily re-use their own ops tables
overriding only specific methods, this patch implements poor man's
class inheritance.  An ops table has ->inherits field which can be set
to any ops table as long as it doesn't create a loop.  When the host
is started, the inheritance chain is followed and any operation which
isn't specified is taken from the nearest ancestor which has it
specified.  This operation is called finalization and done only once
per an ops table and the LLD doesn't have to do anything special about
it other than making the ops table non-const such that libata can
update it.

libata provides four base ops tables lower drivers can inherit from -
base, sata, pmp, sff and bmdma.  To avoid overriding these ops
accidentaly, these ops are declared const and LLDs should always
inherit these instead of using them directly.

After finalization, all the ops table are identical before and after
the patch except for setting .irq_handler to ata_interrupt in drivers
which didn't use to.  The .irq_handler doesn't have any actual effect
and the field will soon be removed by later patch.

* sata_sx4 is still using old style EH and currently doesn't take
  advantage of ops inheritance.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:17 -04:00
Tejun Heo
358f9a77a6 libata: implement and use ata_noop_irq_clear()
->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
useful for drivers which don't use libata SFF HSM implementation.
However, it's a required callback and many drivers implement their own
noop version as placeholder.  This patch implements ata_noop_irq_clear
and use it to replace those custom placeholders.

Also, SFF drivers which don't support BMDMA don't need to use
ata_bmdma_irq_clear().  It becomes noop if BMDMA address isn't
initialized.  Convert them to use ata_noop_irq_clear().

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:16 -04:00
Tejun Heo
b558edddb1 libata: kill ata_ehi_schedule_probe()
ata_ehi_schedule_probe() was created to hide details of link-resuming
reset magic.  Now that all the softreset workarounds are gone,
scheduling probe is very simple - set probe_mask and request RESET.
Kill ata_ehi_schedule_probe() and open code it.  This also increases
consistency as ata_ehi_schedule_probe() couldn't cover individual
device probings so they were open-coded even when the helper existed.

While at it, define ATA_ALL_DEVICES as mask of all possible devices on
a link and always use it when requesting probe on link level for
simplicity and consistency.  Setting extra bits in the probe_mask
doesn't hurt anybody.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:16 -04:00
Tejun Heo
8cebf274dd libata: kill ATA_LFLAG_SKIP_D2H_BSY
Some controllers can't reliably record the initial D2H FIS after SATA
link is brought online for whatever reason.  Advanced controllers
which don't have traditional TF register based interface often have
this problem as they don't really have the TF registers to update
while the controller and link are being initialized.

SKIP_D2H_BSY works around the problem by skipping the wait for device
readiness before issuing SRST, so for such controllers libata issues
SRST blindly and hopes for the best.

Now that libata defaults to hardreset, this workaround is no longer
necessary.  For controllers which have support for hardreset, SRST is
never issued by itself.  It is only issued as follow-up SRST for
device classification and PMP initialization, so there's no need to
wait for it from prereset.

Kill ATA_LFLAG_SKIP_D2H_BSY.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:16 -04:00
Tejun Heo
cf48062658 libata: prefer hardreset
When both soft and hard resets are available, libata preferred
softreset till now.  The logic behind it was to be softer to devices;
however, this doesn't really help much.  Rationales for the change:

* BIOS may freeze lock certain things during boot and softreset can't
  unlock those.  This by itself is okay but during operation PHY event
  or other error conditions can trigger hardreset and the device may
  end up with different configuration.

  For example, after a hardreset, previously unlockable HPA can be
  unlocked resulting in different device size and thus revalidation
  failure.  Similar condition can occur during or after resume.

* Certain ATAPI devices require hardreset to recover after certain
  error conditions.  On PATA, this is done by issuing the DEVICE RESET
  command.  On SATA, COMRESET has equivalent effect.  The problem is
  that DEVICE RESET needs its own execution protocol.

  For SFF controllers with bare TF access, it can be easily
  implemented but more advanced controllers (e.g. ahci and sata_sil24)
  require specialized implementations.  Simply using hardreset solves
  the problem nicely.

* COMRESET initialization sequence is the norm in SATA land and many
  SATA devices don't work properly if only SRST is used.  For example,
  some PMPs behave this way and libata works around by always issuing
  hardreset if the host supports PMP.

  Like the above example, libata has developed a number of mechanisms
  aiming to promote softreset to hardreset if softreset is not going
  to work.  This approach is time consuming and error prone.

  Also, note that, dependingon how you read the specs, it could be
  argued that PMP fan-out ports require COMRESET to start operation.
  In fact, all the PMPs on the market except one don't work properly
  if COMRESET is not issued to fan-out ports after PMP reset.

* COMRESET is an integral part of SATA connection and any working
  device should be able to handle COMRESET properly.  After all, it's
  the way to signal hardreset during reboot.  This is the most used
  and recommended (at least by the ahci spec) method of resetting
  devices.

So, this patch makes libata prefer hardreset over softreset by making
the following changes.

* Rename ATA_EH_RESET_MASK to ATA_EH_RESET and use it whereever
  ATA_EH_{SOFT|HARD}RESET used to be used.  ATA_EH_{SOFT|HARD}RESET is
  now only used to tell prereset whether soft or hard reset will be
  issued.

* Strip out now unneeded promote-to-hardreset logics from
  ata_eh_reset(), ata_std_prereset(), sata_pmp_std_prereset() and
  other places.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:15 -04:00
Tejun Heo
e52dcc4899 libata: ATA_12/16 doesn't fall into ATAPI_MISC
SAT passthrus don't really fit into ATAPI_MISC class.  SAT passthru
commands always transfer multiple of 512 bytes and variable length
response is not allowed.  This patch creates a separate category -
ATAPI_PASS_THRU - for these.

This fixes HSM violation on "hdparm -I".

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-04 02:43:36 -04:00
Tejun Heo
436d34b362 libata: uninline atapi_cmd_type()
Uninline atapi_cmd_type().  It doesn't really have to be inline and
more case will be added which need to access unexported libata
variable.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-04 02:43:35 -04:00
Bartlomiej Zolnierkiewicz
a4ba7fe2a6 libata: fix IDENTIFY order in ata_bus_probe()
Commit f58229f806 accidentally made
ata_bus_probe() not use reverse order probing.  Fix it.

There currently isn't any PATA driver which uses obsolete
ata_bus_probe() path, so this patch is mainly for correctness.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-04-04 02:43:33 -04:00
Tejun Heo
3ec25ebd69 libata: ATA_EHI_LPM should be ATA_EH_LPM
EH actions are ATA_EH_* not ATA_EHI_*.  Rename ATA_EHI_LPM to
ATA_EH_LPM.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-29 12:21:31 -04:00
Tejun Heo
dda7aba119 libata: improve HPA error handling
There's no point in retrying and eventually failing device detection
when the device rejects READ_NATIVE_MAX[_EXT].  Disable HPA unlocking
if READ_NATIVE_MAX[_EXT] is rejected as done when SET_MAX[_EXT] is
rejected.

This allows some old drives to work even if they aren't blacklisted.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-24 22:09:40 -04:00
Tejun Heo
1ffc151fcd libata: assume no device is attached if both IDENTIFYs are aborted
This is to fix bugzilla #10254.  QSI cdrom attached to pata_sis as
secondary master appears as phantom device for the slave.
Interestingly, instead of not setting DRQ after IDENTIFY which
triggers NODEV_HINT, it aborts both IDENTIFY and IDENTIFY PACKET which
makes EH retry.

Modify EH such that it assumes no device is attached if both flavors
of IDENTIFY are aborted by the device.  There really isn't much point
in retrying when the device actively aborts the commands.

While at it, convert NODEV detection message to ata_dev_printk() to
help debugging obscure detection problems.

This problem was reported by Jan Bücken.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jan Bücken <jb.faq@gmx.de>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-24 22:09:38 -04:00
Tejun Heo
7afb42226a libata: don't allow sysfs read access to force param
Buffer for force param is deallocated after initialization, so trying
to read it via sysfs results in oops.  Don't allow read access to the
param node.

Spotted by Eric Sesterhenn.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-10 20:51:05 -04:00
Harvey Harrison
7f5e4e8d94 ata: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-10 20:50:31 -04:00
Jeff Garzik
72ad6ec489 Revert "power_state: get rid of write-only variable in SATA"
This reverts commit 559bbe6cbd.

Michael S. Tsirkin reports that this changes breaks suspend/resume.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-02-25 17:31:10 -05:00
Adrian Bunk
c5c61bda5e 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>
2008-02-25 17:29:35 -05:00
Randy Dunlap
4cdfa1b3ce libata-core: fix kernel-doc warning
Fix libata-core kernel-doc warning:
Warning(linux-2.6.25-rc2-git6//drivers/ata/libata-core.c:168): No description found for parameter 'ap'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-24 00:28:48 -05:00
Tejun Heo
9116300634 libata: automatically use DMADIR if drive/bridge requires it
Back in 2.6.17-rc2, a libata module parameter was added for atapi_dmadir.

That's nice, but most SATA devices which need it will tell us about it
in their IDENTIFY PACKET response, as bit-15 of word-62 of the
returned data (as per ATA7, ATA8 specifications).

So for those which specify it, we should automatically use the DMADIR bit.
Otherwise, disc writing will fail by default on many SATA-ATAPI drives.

This patch adds ATA_DFLAG_DMADIR and make ata_dev_configure() set it
if atapi_dmadir is set or identify data indicates DMADIR is necessary.
atapi_xlat() is converted to check ATA_DFLAG_DMADIR before setting
DMADIR.

Original patch is from Mark Lord.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-24 00:27:33 -05:00
Pavel Machek
559bbe6cbd power_state: get rid of write-only variable in SATA
power_state is scheduled for removal, and libata uses it in write-only
mode. Remove it.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-24 00:27:26 -05:00
Rafael J. Wysocki
3a2d5b7001 PM: Introduce PM_EVENT_HIBERNATE callback state
During the last step of hibernation in the "platform" mode (with the
help of ACPI) we use the suspend code, including the devices'
->suspend() methods, to prepare the system for entering the ACPI S4
system sleep state.

But at least for some devices the operations performed by the
->suspend() callback in that case must be different from its operations
during regular suspend.

For this reason, introduce the new PM event type PM_EVENT_HIBERNATE and
pass it to the device drivers' ->suspend() methods during the last phase
of hibernation, so that they can distinguish this case and handle it as
appropriate.  Modify the drivers that handle PM_EVENT_SUSPEND in a
special way and need to handle PM_EVENT_HIBERNATE in the same way.

These changes are necessary to fix a hibernation regression related
to the i915 driver (ref. http://lkml.org/lkml/2008/2/22/488).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 10:40:04 -08:00
Tejun Heo
3326732570 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>
2008-02-20 12:12:28 -05:00
James Bottomley
fa2fc7f481 libata: implement drain buffers
This just updates the libata slave configure routine to take advantage
of the block layer drain buffers.  It also adjusts the size lengths in
the atapi code to add the drain buffer to the DMA length so the driver
knows it can rely on it.

I suspect I should also be checking for AHCI as well as ATA_DEV_ATAPI,
but I couldn't see how to do that easily.

tj: * atapi_drain_needed() added such that draining is applied to only
      misc ATAPI commands.
    * q->bounce_gfp used when allocating drain buffer.
    * Now duplicate ATAPI PIO drain logic dropped.
    * ata_dev_printk() used instead of sdev_printk().

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:57 +01:00
James Bottomley
dde2020754 libata: eliminate the home grown dma padding in favour of
that provided by the block layer

ATA requires that all DMA transfers begin and end on word boundaries.
Because of this, a large amount of machinery grew up in ide to adjust
scatterlists on this basis.  However, as of 2.5, the block layer has a
dma_alignment variable which ensures both the beginning and length of a
DMA transfer are aligned on the dma_alignment boundary.  Although the
block layer does adjust the beginning of the transfer to ensure this
happens, it doesn't actually adjust the length, it merely makes sure
that space is allocated for transfers beyond the declared length.  The
upshot of this is that scatterlists may be padded to any size between
the actual length and the length adjusted to the dma_alignment safely
knowing that memory is allocated in this region.

Right at the moment, SCSI takes the default dma_aligment which is on a
512 byte boundary.  Note that this aligment only applies to transfers
coming in from user space.  However, since all kernel allocations are
automatically aligned on a minimum of 32 byte boundaries, it is safe to
adjust them in this manner as well.

tj: * Adjusting sg after padding is done in block layer.  Make libata
      set queue alignment correctly for ATAPI devices and drop broken
      sg mangling from ata_sg_setup().
    * Use request->raw_data_len for ATAPI transfer chunk size.
    * Killed qc->raw_nbytes.
    * Separated out killing qc->n_iter.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:56 +01:00
Tejun Heo
56c819df77 libata: update ATAPI overflow draining
For misc ATAPI commands which transfer variable length data to the
host, overflow can occur due to application or hardware bug.  Such
overflows can be ignored safely as long as overflow data is properly
drained.  libata HSM implementation has this implemented in
__atapi_pio_bytes() and recently updated for 2.6.24-rc but it requires
further improvements.  Improve drain logic such that...

* Report overflow errors using ehi desc mechanism instead of printing
  directly.

* Properly calculate the number of bytes to be drained considering
  actual number of consumed bytes for partial draining.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:35:37 +01:00
Mikko Rapeli
b152fcd341 ide/libata: ST310211A has buggy HPA too
Signed-off-by: Mikko Rapeli <mikko.rapeli@teleca.com>
Tested-by: Bart Champagne <bart@as35701.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-02-19 01:41:25 +01:00
Harvey Harrison
eeb37ac874 ata: fix sparse warning in libata-core.c
rc is used to test the return value and possibly return an error.
No need to redeclare inside the loop.

drivers/ata/libata-core.c:7089:7: warning: symbol 'rc' shadows an earlier one
drivers/ata/libata-core.c:7030:9: originally declared here

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-15 13:50:56 -05:00
Tejun Heo
4055dee7f5 libata: ignore deverr on SETXFER if mode is configured
Some controllers (VIA CX700) raise device error on SETXFER even after
mode configuration succeeded.  Update ata_dev_set_mode() such that
device error is ignored if transfer mode is configured correctly.  To
implement this, device is revalidated even after device error on
SETXFER.

This fixes kernel bugzilla bug 8563.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-11 14:29:47 -05:00
David Milburn
223f95f76d libata-core: unblacklist HITACHI drives
The HITACHI HDS7250SASUN500G and HITACHI HDS7225SBSUN250 drives
do not need to be blacklisted, the NCQ problem has been resolved
with the "sata_nv: fix for completion handling" patch.

Signed-off-by David Milburn <dmilburn@redhat.com>

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-02-06 07:00:30 -05:00
Joe Perches
1967b7ff75 drivers/ata/: Spelling fixes
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-02-03 17:08:11 +02:00
Linus Nilsson
0affa456cb libata: Change "write_data" to "rw" for some function documentations
The documentation for ata_data_xfer and ata_data_xfer_noirq had the 'rw'
parameter named 'write_data'.

Signed-off-by: Linus Nilsson <lajnold@acc.umu.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-29 08:48:17 +11:00
Tejun Heo
4e6b79fa61 libata: factor out ata_pci_activate_sff_host() from ata_pci_one()
Factor out ata_pci_activate_sff_host() from ata_pci_one().  This does
about the same thing as ata_host_activate() but needs to be separate
because SFF controllers use different and multiple IRQs in legacy
mode.

This will be used to make SFF LLD initialization more flexible.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:16 -05:00
Al Viro
4ca4e43964 libata annotations and fixes
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:15 -05:00
Jeff Garzik
442eacc362 libata: make ata_port_queue_task() an internal function
ata_port_queue_task() served a single user:  ata_pio_task()

Rename to ata_pio_queue_task() and un-export it, as nobody outside of
libata-core.c uses it.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-01-23 05:24:15 -05:00
Alan Cox
c5038fc05d libata/pata_it821x: Improve handling of poorly compatible emulations
Some it821x RAID firmwares return 0 for the err return off both devices.
A similar issue occurs with the slave returning 0 not 1 if you plug a
gigabyte sata ramdisk into a controller that fakes two SATA ports as
master/slave on an SFF channel.

The patch does the following

- Allow the 'failed diagnostics' case on both master and slave
- Move the HORKAGE_DIAGNOSTIC check after ->dev_config

This second change also allows IT821x to fix up a problem where we report
drive diagnostic failures when in fact the drive is fine but the
microcontroller firmware doesn't appear to get it right. IT821x clears
the flag again to avoid giving the user bogus warnings about their disk.

The other IT821x change is a bit ugly, we slightly abuse the cable type
hook to fiddle with the identify data for the devices. We could add a new
hook for this but as we have only one offender and no more seeming likely
it seems better to keep libata-core clean.

Please let this sit in -mm briefly, just in case the relaxed checking
breaks some other emulated interface.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-01-23 05:24:15 -05:00
Tejun Heo
0bcc65ad78 libata: make qc->nbytes include extra buffers
qc->nbytes didn't use to include extra buffers setup by libata core
layer and my be odd.  This patch makes qc->nbytes include any extra
buffers setup by libata core layer and guaranteed to be aligned on 4
byte boundary.

This value is to be used to program the host controller.  As this
represents the actual length of buffer available to the controller and
the controller must be able to deal with short transfers for ATAPI
commands which can transfer variable length, this shouldn't break any
controllers while making problems like rounding-down and controllers
choking up on odd transfer bytes much less likely.

The unmodified value is stored in new field qc->raw_nbytes.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:15 -05:00
Tejun Heo
ff2aeb1eb6 libata: convert to chained sg
libata used private sg iterator to handle padding sg.  Now that sg can
be chained, padding can be handled using standard sg ops.  Convert to
chained sg.

* s/qc->__sg/qc->sg/

* s/qc->pad_sgent/qc->extra_sg[]/.  Because chaining consumes one sg
  entry.  There need to be two extra sg entries.  The renaming is also
  for future addition of other extra sg entries.

* Padding setup is moved into ata_sg_setup_extra() which is organized
  in a way that future addition of other extra sg entries is easy.

* qc->orig_n_elem is unused and removed.

* qc->n_elem now contains the number of sg entries that LLDs should
  map.  qc->mapped_n_elem is added to carry the original number of
  mapped sgs for unmapping.

* The last sg of the original sg list is used to chain to extra sg
  list.  The original last sg is pointed to by qc->last_sg and the
  content is stored in qc->saved_last_sg.  It's restored during
  ata_sg_clean().

* All sg walking code has been updated.  Unnecessary assertions and
  checks for conditions the core layer already guarantees are removed.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:14 -05:00
Tejun Heo
f92a26365a libata: change ATA_QCFLAG_DMAMAP semantics
ATA_QCFLAG_DMAMAP was a bit peculiar in that it got set during qc
initialization and cleared if DMA mapping wasn't necessary.  Make it
more straight forward by making the following changes.

* Don't set it during initialization.  Set it after DMA is actually
  mapped.

* Add BUG_ON() to guarantee that there is data to transfer if DMAMAP
  is set.  This always holds for the current code.  The BUG_ON() is
  for docummentation and sanity check.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:14 -05:00
Tejun Heo
001102d785 libata: kill non-sg DMA interface
With atapi_request_sense() converted to use sg, there's no user of
non-sg interface.  Kill non-sg interface.

* ATA_QCFLAG_SINGLE and ATA_QCFLAG_SG are removed.  ATA_QCFLAG_DMAMAP
  is used instead.  (this way no LLD change is necessary)

* qc->buf_virt is removed.

* ata_sg_init_one() and ata_sg_setup_one() are removed.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:14 -05:00
Tejun Heo
55dba3120f libata: update ->data_xfer hook for ATAPI
Depending on how many bytes are transferred as a unit, PIO data
transfer may consume more bytes than requested.  Knowing how much
data is consumed is necessary to determine how much is left for
draining.  This patch update ->data_xfer such that it returns the
number of consumed bytes.

While at it, it also makes the following changes.

* s/adev/dev/
* use READ/WRITE constants for rw indication
* misc clean ups

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-23 05:24:14 -05:00