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Hans de Goede f4ac647694 libata: Add new med_power_with_dipm link_power_management_policy setting
As described by Matthew Garret quite a while back:
https://mjg59.dreamwidth.org/34868.html

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

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

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

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

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

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

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

On my T440s test laptop I get the following power savings when idle:
medium_power		0.9W
med_power_with_dipm	1.2W
min_power		1.2W

Suggested-by: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-09-18 20:22:04 -07:00
Damien Le Moal 7cfdfdc82a libata: Cleanup ata_read_log_page()
The warning message "READ LOG DMA EXT failed, trying unqueued" in
ata_read_log_page() as well as the macro name ATA_HORKAGE_NO_NCQ_LOG
are confusing: the command READ LOG DMA EXT is not an queued NCQ command
unless it is encapsulated in a RECEIVE FPDMA QUEUED command.
From ACS-4 READ LOG DMA EXT description:

"The device processes the READ LOG DMA EXT command in the NCQ feature
set environment (see 4.13.6) if the READ LOG DMA EXT command is
encapsulated in a RECEIVE FPDMA QUEUED command (see 7.30) with the
inputs encapsulated as shown in 7.23.6."

To avoid confusion, fix the warning messsage to mention switching to PIO and
not "unqueued" and rename the macro ATA_HORKAGE_NO_NCQ_LOG to
ATA_HORKAGE_NO_DMA_LOG.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-07-10 13:41:04 -04:00
Christoph Hellwig 818831c8b2 libata: implement SECURITY PROTOCOL IN/OUT
This allows us to use the generic OPAL code with ATA devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-06-05 15:29:22 -04:00
Mauro Carvalho Chehab 9bb9a39ce5 ata: update references for libata documentation
The libata documentation is now using ReST. Update references
to it to point to the new place.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-05-16 11:25:59 -04:00
Linus Torvalds 79f4d1d5c0 Merge branch 'for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata updates from Tejun Heo:

 - Bartlomiej added pata_falcon

 - Christoph is trying to remove use of static 4k buf.  It's still WIP

 - config cleanup around HAS_DMA

 - other fixes and driver-specific changes

* 'for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: (29 commits)
  ata: pata_of_platform: using of_property_read_u32() helper
  pata_atiixp: Don't use unconnected secondary port on SB600/SB700
  libata-sff: Don't scan disabled ports when checking for legacy mode.
  pata_octeon_cf: remove unused local variables from octeon_cf_set_piomode()
  ahci: qoriq: added ls2088a platforms support
  ahci: qoriq: report error when ecc register address is missing in dts
  ahci: qoriq: added a condition to enable dma coherence
  Revert "libata: switch to dynamic allocation instead of ata_scsi_rbuf"
  ahci: imx: fix building without hwmon or thermal
  ata: add Atari Falcon PATA controller driver
  ata: pass queued command to ->sff_data_xfer method
  ata: allow subsystem to be used on m68k arch
  libata: switch to dynamic allocation instead of ata_scsi_rbuf
  libata: don't call ata_scsi_rbuf_fill for command without a response buffer
  libata: call ->scsi_done from ata_scsi_simulate
  libata: remove the done callback from ata_scsi_args
  libata: move struct ata_scsi_args to libata-scsi.c
  libata: avoid global response buffer in atapi_qc_complete
  libata-eh: Use switch() instead of sparse array for protocol strings
  ata: sata_mv: Convert to devm_ioremap_resource()
  ...
2017-02-21 17:21:32 -08:00
Christoph Hellwig b6a05c823f scsi: remove eh_timed_out methods in the transport template
Instead define the timeout behavior purely based on the host_template
eh_timed_out method and wire up the existing transport implementations
in the host templates.  This also clears up the confusion that the
transport template method overrides the host template one, so some
drivers have to re-override the transport template one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-02-06 19:10:03 -05:00
Bartlomiej Zolnierkiewicz 989e0aac1a ata: pass queued command to ->sff_data_xfer method
For Atari Falcon PATA support we need to check the current command
in its ->sff_data_xfer method.  Update core code and all users
accordingly.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-01-10 11:11:17 -05:00
Adam Manzanares 84f95243b5 ata: ATA Command Priority Disabled By Default
Add a sysfs entry to turn on priority information being passed
to a ATA device. By default this feature is turned off.

This patch depends on ata: Enabling ATA Command Priorities

tj: Renamed ncq_prio_on to ncq_prio_enable and removed trivial
    ata_ncq_prio_on() and open-coded the test.

Signed-off-by: Adam Manzanares <adam.manzanares@hgst.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-10-19 14:34:36 -04:00
Adam Manzanares 8e061784b5 ata: Enabling ATA Command Priorities
This patch checks to see if an ATA device supports NCQ command priorities.
If so and the user has specified an iocontext that indicates
IO_PRIO_CLASS_RT then we build a tf with a high priority command.

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

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

Signed-off-by: Adam Manzanares <adam.manzanares@hgst.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-10-19 14:34:36 -04:00
Christoph Hellwig dcd3ea81f5 libata: remove <asm-generic/libata-portmap.h>
asm-generic is only intended for architecture defaults, and we can simply
kill it off by moving the two defintions directly to <linux/libata.h>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-09-22 11:50:29 -04:00
Christoph Hellwig 37f92d77dc ata: define ATA_PROT_* in terms of ATA_PROT_FLAG_*
This avoid the need to always translate between the two in ata_prot_flags
and generally cleans up the taskfile protocol usage.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-18 20:55:38 -04:00
Christoph Hellwig d6e50e379e libata: remove ATA_PROT_FLAG_DATA
Instead we can simply check for PIO or DMA in ata_is_data.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-18 20:55:38 -04:00
Christoph Hellwig eb0effdf53 libata: remove ata_is_nodata
The only caller can just check for !ata_is_data instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-18 20:55:37 -04:00
Hannes Reinecke 5b844b63dd ata: Handle ATA NCQ NO-DATA commands correctly
Add a new taskfile protocol ATA_PROT_NCQ_NODATA to handle
ATA NCQ NO-DATA commands correctly.
And fixup ata_scsi_zbc_out_xlat() to use it.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-15 08:08:13 -04:00
Christoph Hellwig b1c04e80c6 libata: return boolean values from ata_is_*
This way we don't have to worry about the exact bit postition of the
test to leak out and any crazy propagation effects in the callers.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-07-14 10:44:51 -04:00
Hannes Reinecke 6d1003ae8d libata: support host-aware and host-managed ZAC devices
Byte 69 bits 0:1 in the IDENTIFY DEVICE data indicate a
host-aware ZAC device.
Host-managed ZAC devices have their own individual signature,
and to not set the bits in the IDENTIFY DEVICE data.
And whenever we detect a ZAC-compatible device we should
be displaying the zoned block characteristics VPD page.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-05-09 12:36:46 -04:00
Hannes Reinecke 284b3b77ea libata: NCQ encapsulation for ZAC MANAGEMENT OUT
Add NCQ encapsulation for ZAC MANAGEMENT OUT and evaluate
NCQ Non-Data log pages to figure out if NCQ encapsulation
is supported.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-05-09 12:36:46 -04:00
Hannes Reinecke 28a3fc2295 libata: implement ZBC IN translation
ZAC drives implement a 'ZAC Management In' command template,
which maps onto the ZBC IN command.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-05-09 12:36:46 -04:00
Hannes Reinecke 3a92945b24 libata: fixup ZAC device disabling
libata device disabling is ... curious. So add the correct
definitions that we can disable ZAC devices properly.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-05-09 12:36:46 -04:00
Hannes Reinecke 5c65d8bb35 libata: Add command definitions for NCQ Encapsulation for READ LOG DMA EXT
ACS-4 defines an NCQ encapsulation for READ LOG DMA EXT.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-05-09 12:36:45 -04:00
Hannes Reinecke 06dbde5f3a libata: Implement control mode page to select sense format
Implement MODE SELECT for the control mode page to allow the OS
to switch to descriptor sense.

tj: Dropped s/sb/cmd->sense_buffer/ in ata_gen_ata_sense().  Added
    @dev description to ata_msense_ctl_mode().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-04-04 12:07:41 -04:00
Harvey Hunt 4ee34ea3a1 libata: Align ata_device's id on a cacheline
The id buffer in ata_device is a DMA target, but it isn't explicitly
cacheline aligned. Due to this, adjacent fields can be overwritten with
stale data from memory on non coherent architectures. As a result, the
kernel is sometimes unable to communicate with an ATA device.

Fix this by ensuring that the id buffer is cacheline aligned.

This issue is similar to that fixed by Commit 84bda12af3
("libata: align ap->sector_buf").

Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 2.6.18
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-02-25 16:37:06 -05:00
Danesh Petigara fb32963355 drivers: ata: wake port before DMA stop for ALPM
The AHCI driver code stops and starts port DMA engines at will
without considering the power state of the particular port. The
AHCI specification isn't very clear on how to handle this scenario,
leaving implementation open to interpretation.

Broadcom's STB SATA host controller is unable to handle port DMA
controller restarts when the port in question is in low power mode.
When a port enters partial or slumber mode, its PHY is powered down.
When a controller restart is requested, the controller's internal
state machine expects the PHY to be brought back up by software which
never happens in this case, resulting in failures.

To avoid this situation, logic is added to manually wake up the port
just before its DMA engine is stopped, if the port happens to be in
a low power state. HBA initiated power management ensures that the port
eventually returns to its configured low power state, when the link is
idle (as per the conditions listed in the spec). A new host flag is also
added to ensure this logic is only exercised for hosts with the above
limitation.

tj: Formatting changes.

Signed-off-by: Danesh Petigara <dpetigara@broadcom.com>
Reviewed-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-01-25 15:20:44 -05:00
Linus Torvalds 8c930204ce Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata updates from Tejun Heo:
 "Mostly low level driver specific changes.

  Two changes are somewhat noteworthy.  First, Dan's patchset to support
  per-port msix interrupt handling for ahci, which was tried last cycle
  but had to be backed out due to a couple issues, is back and seems to
  be working fine.  Second, libata exception handling now uses
  usleep_range() instead of msleep() for sleeps < 20ms which can make
  things snappier in some corner cases"

* 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  libata: skip debounce delay on link resume
  ata: ahci_brcmstb: disable DIPM support
  ata: ahci_brcmstb: enable support for ALPM
  drivers: libata-core: Use usleep_range() instead of msleep() for short sleeps (<20 ms)
  sata_sx4: correctly handling failed allocation
  ata: ahci_brcmstb: add support for MIPS-based platforms
  ahci: qoriq: Adjust the default register values on ls1021a
  ahci: qoriq: Update the default Rx watermark value
  ahci: qoriq: Adjust the default register values on ls1043a
  ahci: compile out msi/msix infrastructure
  ata: core: fix irq description on AHCI single irq systems
  ata: ahci_brcmstb: remove unused definitions
  ata: ahci_brcmstb: add a quirk for MIPS-based platforms
  ata: ahci_brcmstb: disable NCQ for MIPS-based platforms
  ata: sata_rcar: Remove obsolete platform_device_id entries
  sata_rcar: Add compatible string for r8a7795
  ahci: kill 'intr_status'
  ahci: switch from 'threaded' to 'hardirq' interrupt handling
  ahci: per-port msix support
2016-01-11 19:33:59 -08:00
Danesh Petigara e39b2bb3b7 libata: skip debounce delay on link resume
The link resume logic uses a 200msec delay while debouncing
the SControl register. The rationale behind that delay is
to accommodate some PHYs that behave badly if their SStatus/
SControl registers are pounded immediately on resume.
The Broadcom STB SATA PHY does not seem to have this issue.
This patch introduces a new link flag that allows platforms
to skip the debounce delay if it isn't needed.

Signed-off-by: Danesh Petigara <dpetigara@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-01-08 11:50:14 -05:00
Andreas Werner ea013a9b20 libata-eh.c: Introduce new ata port flag for controller which lockup on read log page
Some controller lockup on a ata_read_log_page.
Add new ata port flag ATA_FLAG_NO_LOG_PAGE which can used
to blacklist a controller.

If this flag is set, any attempt to read a log page returns an error
without actually issuing the command.

Signed-off-by: Andreas Werner <andreas.werner@men.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-12-07 10:25:57 -05:00
Manuel Lauss 8a3e33cf92 ata: ahci: find eSATA ports and flag them as removable
If the AHCI ports' HPCP or ESP bits are set, the port
should be considered external (e.g. eSATA) and is marked
as removable.  Userspace tools like udisks then treat it
like an usb drive.

With this patch applied, when I plug a drive into the esata port,
KDE pops up a window asking what to do with the drives(s), just
like it does for any random USB stick.

Removability is indicated to the upper layers by way of the
SCSI RMB bit, as I haven't found another way to signal
userspace to treat a sata disk like any usb stick.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-09-30 17:37:55 -04:00
David Milburn af34d63763 libata: add ATA_HORKAGE_MAX_SEC_1024 to revert back to previous max_sectors limit
Since no longer limiting max_sectors to BLK_DEF_MAX_SECTORS (commit 34b48db66e),
data corruption may occur on ST380013AS drive configured on 82801JI (ICH10 Family)
SATA controller. This patch will allow the driver to limit max_sectors as before

 # cat /sys/block/sdb/queue/max_sectors_kb
 512

I was able to double the max_sectors_kb value up to 16384 on linux-4.2.0-rc2
before seeing corruption, but seems safer to use previous limit. Without this
patch max_sectors_kb will be 32767.

tj: Minor comment update.

Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David Milburn <dmilburn@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.19 and later
Fixes: 34b48db66e ("block: remove artifical max_hw_sectors cap")
2015-07-15 11:47:24 -04:00
Arne Fitzenreiter 71d126fd28 libata: add ATA_HORKAGE_NOTRIM
Some devices lose data on TRIM whether queued or not.  This patch adds
a horkage to disable TRIM.

tj: Collapsed unnecessary if() nesting.

Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
2015-07-15 11:22:35 -04:00
Linus Torvalds 64e22b8685 Merge branch 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata updates from Tejun Heo:

 - a number of libata core changes to better support NCQ TRIM.

 - ahci now supports MSI-X in single IRQ mode to support a new
   controller which doesn't implement MSI or INTX.

 - ahci now supports edge-triggered IRQ mode to support a new controller
   which for some odd reason did edge-triggered IRQ.

 - the usual controller support additions and changes.

* 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: (27 commits)
  libata: Do not blacklist Micron M500DC
  ata: ahci_mvebu: add suspend/resume support
  ahci, msix: Fix build error for !PCI_MSI
  ahci: Add support for Cavium's ThunderX host controller
  ahci: Add generic MSI-X support for single interrupts to SATA PCI driver
  libata: finally use __initconst in ata_parse_force_one()
  drivers: ata: add support for Ceva sata host controller
  devicetree:bindings: add devicetree bindings for ceva ahci
  ahci: added support for Freescale AHCI sata
  ahci: Store irq number in struct ahci_host_priv
  ahci: Move interrupt enablement code to a separate function
  Doc: libata: Fix spelling typo found in libata.xml
  ata:sata_nv - Change 1 to true for bool type variable.
  ata: add Broadcom AHCI SATA3 driver for STB chips
  Documentation: devicetree: add Broadcom SATA binding
  libata: Fix regression when the NCQ Send and Receive log page is absent
  ata: hpt366: fix constant cast warning
  ata: ahci_xgene: potential NULL dereference in probe
  ata: ahci_xgene: Add AHCI Support for 2nd HW version of APM X-Gene SoC AHCI SATA Host controller.
  libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.
  ...
2015-06-25 16:49:21 -07:00
Linus Torvalds acd53127c4 SCSI misc on 20150622
This is the usual grab bag of driver updates (lpfc, hpsa,
 megaraid_sas, cxgbi, be2iscsi) plus an assortment of minor updates.
 There are also one new driver: the Cisco snic; the advansys driver has
 been rewritten to get rid of the warning about converting it to the
 DMA API, the tape statistics patch got in and finally, there's a
 resuffle of SCSI header files to separate more cleanly initiator from
 target mode (and better share the common definitions).
 
 Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is the usual grab bag of driver updates (lpfc, hpsa,
  megaraid_sas, cxgbi, be2iscsi) plus an assortment of minor updates.

  There is also one new driver: the Cisco snic.  The advansys driver has
  been rewritten to get rid of the warning about converting it to the
  DMA API, the tape statistics patch got in and finally, there's a
  resuffle of SCSI header files to separate more cleanly initiator from
  target mode (and better share the common definitions)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (156 commits)
  snic: driver for Cisco SCSI HBA
  qla2xxx: Fix indentation
  qla2xxx: Comment out unreachable code
  fusion: remove dead MTRR code
  advansys: fix compilation errors and warnings when CONFIG_PCI is not set
  mptsas: fix depth param in scsi_track_queue_full
  megaraid: fix irq setup process regression
  lpfc: Update version to 10.7.0.0 for upstream patch set.
  lpfc: Fix to drop PLOGIs from fabric node till LOGO processing completes
  lpfc: Fix scsi task management error message.
  lpfc: Fix cq_id masking problem.
  lpfc: Fix scsi prep dma buf error.
  lpfc: Add support for using block multi-queue
  lpfc: Devices are not discovered during takeaway/giveback testing
  lpfc: Fix vport deletion failure.
  lpfc: Check for active portpeerbeacon.
  lpfc: Update driver version for upstream patch set 10.6.0.1.
  lpfc: Change buffer pool empty message to miscellaneous category
  lpfc: Fix incorrect log message reported for empty FCF record.
  lpfc: Fix rport leak.
  ...
2015-06-23 15:55:44 -07:00
Hannes Reinecke b84b1d522f scsi: Do not set cmd_per_lun to 1 in the host template
'0' is now used as the default cmd_per_lun value,
so there's no need to explicitly set it to '1' in the
host template.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-05-31 18:06:28 -07:00
Martin K. Petersen 5d3abf8ff6 libata: Fall back to unqueued READ LOG EXT if the DMA variant fails
Some devices advertise support for the READ/WRITE LOG DMA EXT commands
but fail when we try to issue them. This can lead to queued TRIM being
unintentionally disabled since the relevant feature flag is located in a
general purpose log page.

Fall back to unqueued READ LOG EXT if the DMA variant fails while
reading a log page.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-05-05 09:30:19 -04:00
Gabriele Mazzotta 09c5b4803a libata: Ignore spurious PHY event on LPM policy change
When the LPM policy is set to ATA_LPM_MAX_POWER, the device might
generate a spurious PHY event that cuases errors on the link.
Ignore this event if it occured within 10s after the policy change.

The timeout was chosen observing that on a Dell XPS13 9333 these
spurious events can occur up to roughly 6s after the policy change.

Link: http://lkml.kernel.org/g/3352987.ugV1Ipy7Z5@xps13
Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
2015-04-25 16:50:14 -04:00
Gabriele Mazzotta 8393b811f3 libata: Add helper to determine when PHY events should be ignored
This is a preparation commit that will allow to add other criteria
according to which PHY events should be dropped.

Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
2015-04-25 16:50:14 -04:00
Linus Torvalds a1480a166d Merge branch 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata updates from Tejun Heo:

 - Hannes's patchset implements support for better error reporting
   introduced by the new ATA command spec.

 - the deperecated pci_ dma API usages have been replaced by dma_ ones.

 - a bunch of hardware specific updates and some cleanups.

* 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ata: remove deprecated use of pci api
  ahci: st: st_configure_oob must be called after IP is clocked.
  ahci: st: Update the ahci_st DT documentation
  ahci: st: Update the DT example for how to obtain the PHY.
  sata_dwc_460ex: indent an if statement
  libata: Add tracepoints
  libata-eh: Set 'information' field for autosense
  libata: Implement support for sense data reporting
  libata: Implement NCQ autosense
  libata: use status bit definitions in ata_dump_status()
  ide,ata: Rename ATA_IDX to ATA_SENSE
  libata: whitespace fixes in ata_to_sense_error()
  libata: whitespace cleanup in ata_get_cmd_descript()
  libata: use READ_LOG_DMA_EXT
  libata: remove ATA_FLAG_LOWTAG
  sata_dwc_460ex: re-use hsdev->dev instead of dwc_dev
  sata_dwc_460ex: move to generic DMA driver
  sata_dwc_460ex: join messages back
  sata: xgene: add ACPI support for APM X-Gene SATA ports
  ata: sata_mv: add proper definitions for LP_PHY_CTL register values
2015-04-13 16:42:16 -07:00
Tejun Heo 3a02824396 libata: remove ATA_FLAG_LOWTAG
sata_sil24 for some reason pukes when tags are allocated round-robin
which helps tag ordered controllers.  To work around the issue,
72dd299d50 ("libata: allow sata_sil24 to opt-out of tag ordered
submission") introduced ATA_FLAG_LOWTAG which tells libata tag
allocation to do lowest-first.

However, with the recent switch to blk-mq tag allocation, the liata
tag allocation code path is no longer used and the workaround is now
implemented in the block layer and selected by setting
scsi_host_template->tag_alloc_policy to BLK_TAG_ALLOC_FIFO.  See
9269e23496 ("libata: make sata_sil24 use fifo tag allocator").

This leaves ATA_FLAG_LOWTAG withoout any actual user.  Remove it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Dan Williams <dan.j.williams@intel.com>
2015-03-24 14:14:18 -04:00
Shaohua Li 5067c0469c ata: Add a new flag to destinguish sas controller
SAS controller has its own tag allocation, which doesn't directly match to ATA
tag, so SAS and SATA have different code path for ata tags. Originally we use
port->scsi_host (98bd4be1) to destinguish SAS controller, but libsas set
->scsi_host too, so we can't use it for the destinguish, we add a new flag for
this purpose.

Without this patch, the following oops can happen because scsi-mq uses
a host-wide tag map shared among all devices with some integer tag
values >= ATA_MAX_QUEUE.  These unexpectedly high tag values cause
__ata_qc_from_tag() to return NULL, which is then dereferenced in
ata_qc_new_init().

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
  IP: [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
  PGD 32adf0067 PUD 32adf1067 PMD 0
  Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
  Modules linked in: iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi igb
  i2c_algo_bit ptp pps_core pm80xx libsas scsi_transport_sas sg coretemp
  eeprom w83795 i2c_i801
  CPU: 4 PID: 1450 Comm: cydiskbench Not tainted 4.0.0-rc3 #1
  Hardware name: Supermicro X8DTH-i/6/iF/6F/X8DTH, BIOS 2.1b       05/04/12
  task: ffff8800ba86d500 ti: ffff88032a064000 task.ti: ffff88032a064000
  RIP: 0010:[<ffffffff804fd46e>]  [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
  RSP: 0018:ffff88032a067858  EFLAGS: 00010046
  RAX: 0000000000000000 RBX: ffff8800ba0d2230 RCX: 000000000000002a
  RDX: ffffffff80505ae0 RSI: 0000000000000020 RDI: ffff8800ba0d2230
  RBP: ffff88032a067868 R08: 0000000000000201 R09: 0000000000000001
  R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800ba0d0000
  R13: ffff8800ba0d2230 R14: ffffffff80505ae0 R15: ffff8800ba0d0000
  FS:  0000000041223950(0063) GS:ffff88033e480000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 0000000000000058 CR3: 000000032a0a3000 CR4: 00000000000006e0
  Stack:
   ffff880329eee758 ffff880329eee758 ffff88032a0678a8 ffffffff80502dad
   ffff8800ba167978 ffff880329eee758 ffff88032bf9c520 ffff8800ba167978
   ffff88032bf9c520 ffff88032bf9a290 ffff88032a0678b8 ffffffff80506909
  Call Trace:
   [<ffffffff80502dad>] ata_scsi_translate+0x3d/0x1b0
   [<ffffffff80506909>] ata_sas_queuecmd+0x149/0x2a0
   [<ffffffffa0046650>] sas_queuecommand+0xa0/0x1f0 [libsas]
   [<ffffffff804ea544>] scsi_dispatch_cmd+0xd4/0x1a0
   [<ffffffff804eb50f>] scsi_queue_rq+0x66f/0x7f0
   [<ffffffff803e5098>] __blk_mq_run_hw_queue+0x208/0x3f0
   [<ffffffff803e54b8>] blk_mq_run_hw_queue+0x88/0xc0
   [<ffffffff803e5c74>] blk_mq_insert_request+0xc4/0x130
   [<ffffffff803e0b63>] blk_execute_rq_nowait+0x73/0x160
   [<ffffffffa0023fca>] sg_common_write+0x3da/0x720 [sg]
   [<ffffffffa0025100>] sg_new_write+0x250/0x360 [sg]
   [<ffffffffa0025feb>] sg_write+0x13b/0x450 [sg]
   [<ffffffff8032ec91>] vfs_write+0xd1/0x1b0
   [<ffffffff8032ee54>] SyS_write+0x54/0xc0
   [<ffffffff80689932>] system_call_fastpath+0x12/0x17

tj: updated description.

Fixes: 12cb5ce101 ("libata: use blk taging")
Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-03-19 14:14:43 -04:00
Linus Torvalds 8494bcf5b7 Merge branch 'for-3.20/drivers' of git://git.kernel.dk/linux-block
Pull block driver changes from Jens Axboe:
 "This contains:

   - The 4k/partition fixes for brd from Boaz/Matthew.

   - A few xen front/back block fixes from David Vrabel and Roger Pau
     Monne.

   - Floppy changes from Takashi, cleaning the device file creation.

   - Switching libata to use the new blk-mq tagging policy, removing
     code (and a suboptimal implementation) from libata.  This will
     throw you a merge conflict, since a bug in the original libata
     tagging code was fixed since this code was branched.  Trivial.
     From Shaohua.

   - Conversion of loop to blk-mq, from Ming Lei.

   - Cleanup of the io_schedule() handling in bsg from Peter Zijlstra.
     He claims it improves on unreadable code, which will cost him a
     beer.

   - Maintainer update or NDB, now handled by Markus Pargmann.

   - NVMe:
        - Optimization from me that avoids a kmalloc/kfree per IO for
          smaller (<= 8KB) IO. This cuts about 1% of high IOPS CPU
          overhead.
        - Removal of (now) dead RCU code, a relic from before NVMe was
          converted to blk-mq"

* 'for-3.20/drivers' of git://git.kernel.dk/linux-block:
  xen-blkback: default to X86_32 ABI on x86
  xen-blkfront: fix accounting of reqs when migrating
  xen-blkback,xen-blkfront: add myself as maintainer
  block: Simplify bsg complete all
  floppy: Avoid manual call of device_create_file()
  NVMe: avoid kmalloc/kfree for smaller IO
  MAINTAINERS: Update NBD maintainer
  libata: make sata_sil24 use fifo tag allocator
  libata: move sas ata tag allocation to libata-scsi.c
  libata: use blk taging
  NVMe: within nvme_free_queues(), delete RCU sychro/deferred free
  null_blk: suppress invalid partition info
  brd: Request from fdisk 4k alignment
  brd: Fix all partitions BUGs
  axonram: Fix bug in direct_access
  loop: add blk-mq.h include
  block: loop: don't handle REQ_FUA explicitly
  block: loop: introduce lo_discard() and lo_req_flush()
  block: loop: say goodby to bio
  block: loop: improve performance via blk-mq
2015-02-12 14:30:53 -08:00
Tejun Heo b12aa1f25e Merge branch 'for-3.19-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata into for-3.20
09c32aaa36 ("ahci_xgene: Fix the dma state machine lockup for the
ATA_CMD_SMART PIO mode command.") missed 3.19 release.  Fold it into
for-3.20.

Signed-off-by: Tejun Heo <tj@kernel.org>
2015-02-09 07:54:41 -05:00
Akinobu Mita 018d5ef204 ata: ahci_platform: fix owner module reference mismatch for scsi host
The owner module reference of the ahci platform's scsi_host is
initialized to libahci_platform's one, because these drivers use a
scsi_host_template defined in libahci_platform.  So these drivers can
be unloaded even if the scsi device is being accessed.

This fixes it by pushing the scsi_host_template from libahci_platform
to all leaf drivers.  The scsi_host_template is passed through a new
argument of ahci_platform_init_host().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-ide@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
2015-01-28 18:45:23 -05:00
Shaohua Li 12cb5ce101 libata: use blk taging
libata uses its own tag management which is duplication and the
implementation is poor. And if we switch to blk-mq, tag is build-in.
It's time to switch to generic taging.

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

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

Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-23 14:19:04 -07:00
Dan Williams 72dd299d50 libata: allow sata_sil24 to opt-out of tag ordered submission
Ronny reports: https://bugzilla.kernel.org/show_bug.cgi?id=87101
    "Since commit 8a4aeec8d "libata/ahci: accommodate tag ordered
    controllers" the access to the harddisk on the first SATA-port is
    failing on its first access. The access to the harddisk on the
    second port is working normal.

    When reverting the above commit, access to both harddisks is working
    fine again."

Maintain tag ordered submission as the default, but allow sata_sil24 to
continue with the old behavior.

Cc: <stable@vger.kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Reported-by: Ronny Hegewald <Ronny.Hegewald@online.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-01-19 09:10:07 -05:00
Martin K. Petersen e61f7d1c3c libata: Whitelist SSDs that are known to properly return zeroes after TRIM
As defined, the DRAT (Deterministic Read After Trim) and RZAT (Return
Zero After Trim) flags in the ATA Command Set are unreliable in the
sense that they only define what happens if the device successfully
executed the DSM TRIM command. TRIM is only advisory, however, and the
device is free to silently ignore all or parts of the request.

In practice this renders the DRAT and RZAT flags completely useless and
because the results are unpredictable we decided to disable discard in
MD for 3.18 to avoid the risk of data corruption.

Hardware vendors in the real world obviously need better guarantees than
what the standards bodies provide. Unfortuntely those guarantees are
encoded in product requirements documents rather than somewhere we can
key off of them programatically. So we are compelled to disabling
discard_zeroes_data for all devices unless we explicitly have data to
support whitelisting them.

This patch whitelists SSDs from a few of the main vendors. None of the
whitelists are based on written guarantees. They are purely based on
empirical evidence collected from internal and external users that have
tested or qualified these drives in RAID deployments.

The whitelist is only meant as a starting point and is by no means
comprehensive:

   - All intel SSD models except for 510
   - Micron M5?0/M600
   - Samsung SSDs
   - Seagate SSDs

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2015-01-08 10:35:40 -05:00
Linus Torvalds 4e8790f77f Merge branch 'for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata changes from Tejun Heo:
 "The only interesting piece is the support for shingled drives.  The
  changes in libata layer are minimal.  All it does is identifying the
  new class of device and report upwards accordingly"

* 'for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  libata: Remove FIXME comment in atapi_request_sense()
  sata_rcar: Document deprecated "renesas,rcar-sata"
  sata_rcar: Add clocks to sata_rcar bindings
  ahci_sunxi: Make AHCI_HFLAG_NO_PMP flag configurable with a module option
  libata-scsi: Update SATL for ZAC drives
  libata: Implement ATA_DEV_ZAC
  libsas: use ata_dev_classify()
2014-12-11 18:52:37 -08:00
Christoph Hellwig db5ed4dfd5 scsi: drop reason argument from ->change_queue_depth
Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24 14:45:27 +01:00
Hannes Reinecke 9162c6579b libata: Implement ATA_DEV_ZAC
Add new ATA device type for ZAC devices.

Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-11-05 11:22:06 -05:00
Joe Perches d7bead1b88 libata: change ata_<foo>_printk routines to return void
The return value is not used by callers of these functions nor
by uses of all macros so change the functions to return void.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-09-23 10:02:31 -04:00
Tejun Heo 1a112d10f0 libata: introduce ata_host->n_tags to avoid oops on SAS controllers
1871ee134b ("libata: support the ata host which implements a queue
depth less than 32") directly used ata_port->scsi_host->can_queue from
ata_qc_new() to determine the number of tags supported by the host;
unfortunately, SAS controllers doing SATA don't initialize ->scsi_host
leading to the following oops.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
 IP: [<ffffffff814e0618>] ata_qc_new_init+0x188/0x1b0
 PGD 0
 Oops: 0002 [#1] SMP
 Modules linked in: isci libsas scsi_transport_sas mgag200 drm_kms_helper ttm
 CPU: 1 PID: 518 Comm: udevd Not tainted 3.16.0-rc6+ #62
 Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013
 task: ffff880c1a00b280 ti: ffff88061a000000 task.ti: ffff88061a000000
 RIP: 0010:[<ffffffff814e0618>]  [<ffffffff814e0618>] ata_qc_new_init+0x188/0x1b0
 RSP: 0018:ffff88061a003ae8  EFLAGS: 00010012
 RAX: 0000000000000001 RBX: ffff88000241ca80 RCX: 00000000000000fa
 RDX: 0000000000000020 RSI: 0000000000000020 RDI: ffff8806194aa298
 RBP: ffff88061a003ae8 R08: ffff8806194a8000 R09: 0000000000000000
 R10: 0000000000000000 R11: ffff88000241ca80 R12: ffff88061ad58200
 R13: ffff8806194aa298 R14: ffffffff814e67a0 R15: ffff8806194a8000
 FS:  00007f3ad7fe3840(0000) GS:ffff880627620000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000058 CR3: 000000061a118000 CR4: 00000000001407e0
 Stack:
  ffff88061a003b20 ffffffff814e96e1 ffff88000241ca80 ffff88061ad58200
  ffff8800b6bf6000 ffff880c1c988000 ffff880619903850 ffff88061a003b68
  ffffffffa0056ce1 ffff88061a003b48 0000000013d6e6f8 ffff88000241ca80
 Call Trace:
  [<ffffffff814e96e1>] ata_sas_queuecmd+0xa1/0x430
  [<ffffffffa0056ce1>] sas_queuecommand+0x191/0x220 [libsas]
  [<ffffffff8149afee>] scsi_dispatch_cmd+0x10e/0x300
  [<ffffffff814a3bc5>] scsi_request_fn+0x2f5/0x550
  [<ffffffff81317613>] __blk_run_queue+0x33/0x40
  [<ffffffff8131781a>] queue_unplugged+0x2a/0x90
  [<ffffffff8131ceb4>] blk_flush_plug_list+0x1b4/0x210
  [<ffffffff8131d274>] blk_finish_plug+0x14/0x50
  [<ffffffff8117eaa8>] __do_page_cache_readahead+0x198/0x1f0
  [<ffffffff8117ee21>] force_page_cache_readahead+0x31/0x50
  [<ffffffff8117ee7e>] page_cache_sync_readahead+0x3e/0x50
  [<ffffffff81172ac6>] generic_file_read_iter+0x496/0x5a0
  [<ffffffff81219897>] blkdev_read_iter+0x37/0x40
  [<ffffffff811e307e>] new_sync_read+0x7e/0xb0
  [<ffffffff811e3734>] vfs_read+0x94/0x170
  [<ffffffff811e43c6>] SyS_read+0x46/0xb0
  [<ffffffff811e33d1>] ? SyS_lseek+0x91/0xb0
  [<ffffffff8171ee29>] system_call_fastpath+0x16/0x1b
 Code: 00 00 00 88 50 29 83 7f 08 01 19 d2 83 e2 f0 83 ea 50 88 50 34 c6 81 1d 02 00 00 40 c6 81 17 02 00 00 00 5d c3 66 0f 1f 44 00 00 <89> 14 25 58 00 00 00

Fix it by introducing ata_host->n_tags which is initialized to
ATA_MAX_QUEUE - 1 in ata_host_init() for SAS controllers and set to
scsi_host_template->can_queue in ata_host_register() for !SAS ones.
As SAS hosts are never registered, this will give them the same
ATA_MAX_QUEUE - 1 as before.  Note that we can't use
scsi_host->can_queue directly for SAS hosts anyway as they can go
higher than the libata maximum.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Reported-by: Jesse Brandeburg <jesse.brandeburg@gmail.com>
Reported-by: Peter Hurley <peter@hurleysoftware.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Fixes: 1871ee134b ("libata: support the ata host which implements a queue depth less than 32")
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: stable@vger.kernel.org
2014-07-23 10:30:34 -04:00
Dan Williams 8a4aeec8d2 libata/ahci: accommodate tag ordered controllers
The AHCI spec allows implementations to issue commands in tag order
rather than FIFO order:

	5.3.2.12 P:SelectCmd
	HBA sets pSlotLoc = (pSlotLoc + 1) mod (CAP.NCS + 1)
	or HBA selects the command to issue that has had the
	PxCI bit set to '1' longer than any other command
	pending to be issued.

The result is that commands posted sequentially (time-wise) may play out
of sequence when issued by hardware.

This behavior has likely been hidden by drives that arrange for commands
to complete in issue order.  However, it appears recent drives (two from
different vendors that we have found so far) inflict out-of-order
completions as a matter of course.  So, we need to take care to maintain
ordered submission, otherwise we risk triggering a drive to fall out of
sequential-io automation and back to random-io processing, which incurs
large latency and degrades throughput.

This issue was found in simple benchmarks where QD=2 seq-write
performance was 30-50% *greater* than QD=32 seq-write performance.

Tagging for -stable and making the change globally since it has a low
risk-to-reward ratio.  Also, word is that recent versions of an unnamed
OS also does it this way now.  So, drives in the field are already
experienced with this tag ordering scheme.

Cc: <stable@vger.kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ed Ciechanowski <ed.ciechanowski@intel.com>
Reviewed-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-04-18 15:56:03 -04:00