Commit Graph

389 Commits

Author SHA1 Message Date
Bart Van Assche
613be1f626 [SCSI] remove a useless get/put_device pair in scsi_request_fn
SCSI devices may only be removed by calling scsi_remove_device().
That function must invoke blk_cleanup_queue() before the final put
of sdev->sdev_gendev. Since blk_cleanup_queue() waits for the
block queue to drain and then tears it down, scsi_request_fn cannot
be active anymore after blk_cleanup_queue() has returned and hence
the get_device()/put_device() pair in scsi_request_fn is unnecessary.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:25 -07:00
Christoph Hellwig
0479633686 [SCSI] do not manipulate device reference counts in scsi_get/put_command
Many callers won't need this and we can optimize them away.  In addition
the handling in the __-prefixed variants was inconsistant to start with.

Based on an earlier patch from Bart Van Assche.

[jejb: fix kerneldoc probelm picked up by Fengguang Wu]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:24 -07:00
Christoph Hellwig
21a05df547 [SCSI] avoid taking host_lock in scsi_run_queue unless nessecary
If we don't have starved devices we don't need to take the host lock
to iterate over them.  Also split the function up to be more clear.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:24 -07:00
Eiichi Tsukata
ee60b2c52e [SCSI] Add timeout to avoid infinite command retry
Currently, scsi error handling in scsi_io_completion() tries to
unconditionally requeue scsi command when device keeps some error state.
For example, UNIT_ATTENTION causes infinite retry with
action == ACTION_RETRY.
This is because retryable errors are thought to be temporary and the scsi
device will soon recover from those errors. Normally, such retry policy is
appropriate because the device will soon recover from temporary error state.

But there is no guarantee that device is able to recover from error state
immediately. Some hardware error can prevent device from recovering.

This patch adds timeout in scsi_io_completion() to avoid infinite command
retry in scsi_io_completion(). Once scsi command retry time is longer than
this timeout, the command is treated as failure.

Signed-off-by: Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15 10:19:19 -07:00
Russell King
e83b366487 Fix uses of dma_max_pfn() when converting to a limiting address
We must use a 64-bit for this, otherwise overflowed bits get lost, and
that can result in a lower than intended value set.

Fixes: 8e0cb8a1f6 ("ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations")
Fixes: 7d35496dd9 ("ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations")
Tested-Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-17 23:08:41 +00:00
Santosh Shilimkar
7d35496dd9 ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations
DMA bounce limit is the maximum direct DMA'able memory beyond which
bounce buffers has to be used to perform dma operations. SCSI driver
relies on dma_mask but its calculation is based on max_*pfn which
don't have uniform meaning across architectures. So make use of
dma_max_pfn() which is expected to return the DMAable maximum pfn
value across architectures.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-31 14:49:26 +00:00
Linus Torvalds
357397a141 Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata changes from Tejun Heo:
 "Two interesting changes.

   - libata acpi handling has been restructured so that the association
     between ata devices and ACPI handles are less convoluted.  This
     change shouldn't change visible behavior.

   - Queued TRIM support, which enables sending TRIM to the device
     without draining in-flight RW commands, is added.  Currently only
     enabled for ahci (and likely to stay that way for the foreseeable
     future).

  Other changes are driver-specific updates / fixes"

* 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  libata: bugfix: Remove __le32 in ata_tf_to_fis()
  libata: acpi: Remove ata_dev_acpi_handle stub in libata.h
  libata: Add support for queued DSM TRIM
  libata: Add support for SEND/RECEIVE FPDMA QUEUED
  libata: Add H2D FIS "auxiliary" port flag
  libata: Populate host-to-device FIS "auxiliary" field
  ata: acpi: rework the ata acpi bind support
  sata, highbank: send extra clock cycles in SGPIO patterns
  sata, highbank: set tx_atten override bits
  devicetree: create a separate binding description for sata_highbank
  drivers/ata/sata_rcar.c: simplify use of devm_ioremap_resource
  sata highbank: enable 64-bit DMA mask when using LPAE
  ata: pata_samsung_cf: add missing __iomem annotation
  ata: pata_arasan: Staticize local symbols
  sata_mv: Remove unneeded CONFIG_HAVE_CLK ifdefs
  ata: use dev_get_platdata()
  sata_mv: Remove unneeded forward declaration
  libata: acpi: remove dead code for ata_acpi_(un)bind
  libata: move 'struct ata_taskfile' and friends from ata.h to libata.h
2013-09-03 18:19:53 -07:00
Ewan D. Milne
279afdfe78 [SCSI] Generate uevents on certain unit attention codes
Generate a uevent when the following Unit Attention ASC/ASCQ
codes are received:

    2A/01  MODE PARAMETERS CHANGED
    2A/09  CAPACITY DATA HAS CHANGED
    38/07  THIN PROVISIONING SOFT THRESHOLD REACHED
    3F/03  INQUIRY DATA HAS CHANGED
    3F/0E  REPORTED LUNS DATA HAS CHANGED

Log kernel messages when the following Unit Attention ASC/ASCQ
codes are received that are not as specific as those above:

    2A/xx  PARAMETERS CHANGED
    3F/xx  TARGET OPERATING CONDITIONS HAVE CHANGED

Added logic to set expecting_lun_change for other LUNs on the target
after REPORTED LUNS DATA HAS CHANGED is received, so that duplicate
uevents are not generated, and clear expecting_lun_change when a
REPORT LUNS command completes, in accordance with the SPC-3
specification regarding reporting of the 3F 0E ASC/ASCQ UA.

[jejb: remove SPC3 test in scsi_report_lun_change and some docbook fixes and
       unused variable fix, both reported by Fengguang Wu]
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-26 18:52:27 +04:00
Hannes Reinecke
7e782af576 [SCSI] Return ENODATA on medium error
When a medium error is detected the SCSI stack should return
ENODATA to the upper layers.

[jejb: fix whitespace error]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 12:54:53 -04:00
Hannes Reinecke
a9d6ceb838 [SCSI] return ENOSPC on thin provisioning failure
When the thin provisioning hard threshold is reached we
should return ENOSPC to inform upper layers about this fact.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 12:43:54 -04:00
Hannes Reinecke
0f7f6234d3 [SCSI] Document enhanced error codes
Document the various error codes returned on I/O failure.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-23 12:31:59 -04:00
Aaron Lu
f1bc1e4c44 ata: acpi: rework the ata acpi bind support
Binding ACPI handle to SCSI device has several drawbacks, namely:
1 During ATA device initialization time, ACPI handle will be needed
  while SCSI devices are not created yet. So each time ACPI handle is
  needed, instead of retrieving the handle by ACPI_HANDLE macro,
  a namespace scan is performed to find the handle for the corresponding
  ATA device. This is inefficient, and also expose a restriction on
  calling path not holding any lock.
2 The binding to SCSI device tree makes code complex, while at the same
  time doesn't bring us any benefit. All ACPI handlings are still done
  in ATA module, not in SCSI.

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

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

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Dirk Griesbach <spamthis@freenet.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-23 12:09:23 -04:00
Bart Van Assche
0516c08d10 [SCSI] enable destruction of blocked devices which fail LUN scanning
If something goes wrong during LUN scanning, e.g. a transport layer
failure occurs, then __scsi_remove_device() can get invoked by the
LUN scanning code for a SCSI device in state SDEV_CREATED_BLOCK and
before the SCSI device has been added to sysfs (is_visible == 0).
Make sure that even in this case the transition into state SDEV_DEL
occurs. This avoids that __scsi_remove_device() can get invoked a
second time by scsi_forget_host() if this last function is invoked
from another thread than the thread that performs LUN scanning.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-07-09 12:14:09 +01:00
James Bottomley
e2eb7244bc [SCSI] Fix race between starved list and device removal
scsi_run_queue() examines all SCSI devices that are present on
the starved list. Since scsi_run_queue() unlocks the SCSI host
lock a SCSI device can get removed after it has been removed
from the starved list and before its queue is run. Protect
against that race condition by holding a reference on the
queue while running it.

Reported-by: Chanho Min <chanho.min@lge.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-07-09 12:14:08 +01:00
Lin Ming
9b21493c45 [SCSI] sd: use REQ_PM in sd's runtime suspend operation
With the introduction of REQ_PM, modify sd's runtime suspend operation
functions to use that flag so that the operations to put the device into
runtime suspended state(i.e. sync cache and stop device) will not affect
its runtime PM status.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-06 12:48:17 -07:00
Rafael J. Wysocki
53540098b2 ACPI / glue: Add .match() callback to struct acpi_bus_type
USB uses the .find_bridge() callback from struct acpi_bus_type
incorrectly, because as a result of the way it is used by USB every
device in the system that doesn't have a bus type or parent is
passed to usb_acpi_find_device() for inspection.

What USB actually needs, though, is to call usb_acpi_find_device()
for USB ports that don't have a bus type defined, but have
usb_port_device_type as their device type, as well as for USB
devices.

To fix that replace the struct bus_type pointer in struct
acpi_bus_type used for matching devices to specific subsystems
with a .match() callback to be used for this purpose and update
the users of struct acpi_bus_type, including USB, accordingly.
Define the .match() callback routine for USB, usb_acpi_bus_match(),
in such a way that it will cover both USB devices and USB ports
and remove the now redundant .find_bridge() callback pointer from
usb_acpi_bus.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
2013-03-04 14:23:40 +01:00
Aaron Lu
6f4c827e68 [libata] scsi: no poll when ODD is powered off
When the ODD is powered off, any action the user did to the ODD that
would generate a media event will trigger an ACPI interrupt, so the
poll for media event is no longer necessary. And the poll will also
cause a runtime status change, which will stop the ODD from staying in
powered off state, so the poll should better be stopped.

But since we don't have access to the gendisk structure in LLDs, here
comes the disk_events_disable_depth for scsi device. This field is a
hint set by LLDs to convey information to upper layer drivers. A value
of 0 means media poll is necessary for the device, while values above 0
means media poll is not needed and should better be skipped. So we can
increase its value when we are to power off the ODD in ATA layer and
decrease its value when the ODD is powered on, effectively silence the
media events poll.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2013-01-25 15:36:43 -05:00
Linus Torvalds
60da5bf47d Merge branch 'for-3.8/core' of git://git.kernel.dk/linux-block
Pull block layer core updates from Jens Axboe:
 "Here are the core block IO bits for 3.8.  The branch contains:

   - The final version of the surprise device removal fixups from Bart.

   - Don't hide EFI partitions under advanced partition types.  It's
     fairly wide spread these days.  This is especially dangerous for
     systems that have both msdos and efi partition tables, where you
     want to keep them in sync.

   - Cleanup of using -1 instead of the proper NUMA_NO_NODE

   - Export control of bdi flusher thread CPU mask and default to using
     the home node (if known) from Jeff.

   - Export unplug tracepoint for MD.

   - Core improvements from Shaohua.  Reinstate the recursive merge, as
     the original bug has been fixed.  Add plugging for discard and also
     fix a problem handling non pow-of-2 discard limits.

  There's a trivial merge in block/blk-exec.c due to a fix that went
  into 3.7-rc at a later point than -rc4 where this is based."

* 'for-3.8/core' of git://git.kernel.dk/linux-block:
  block: export block_unplug tracepoint
  block: add plug for blkdev_issue_discard
  block: discard granularity might not be power of 2
  deadline: Allow 0ms deadline latency, increase the read speed
  partitions: enable EFI/GPT support by default
  bsg: Remove unused function bsg_goose_queue()
  block: Make blk_cleanup_queue() wait until request_fn finished
  block: Avoid scheduling delayed work on a dead queue
  block: Avoid that request_fn is invoked on a dead queue
  block: Let blk_drain_queue() caller obtain the queue lock
  block: Rename queue dead flag
  bdi: add a user-tunable cpu_list for the bdi flusher threads
  block: use NUMA_NO_NODE instead of -1
  block: recursive merge requests
  block CFQ: avoid moving request to different queue
2012-12-17 08:27:23 -08:00
Bart Van Assche
3f3299d5c0 block: Rename queue dead flag
QUEUE_FLAG_DEAD is used to indicate that queuing new requests must
stop. After this flag has been set queue draining starts. However,
during the queue draining phase it is still safe to invoke the
queue's request_fn, so QUEUE_FLAG_DYING is a better name for this
flag.

This patch has been generated by running the following command
over the kernel source tree:

git grep -lEw 'blk_queue_dead|QUEUE_FLAG_DEAD' |
    xargs sed -i.tmp -e 's/blk_queue_dead/blk_queue_dying/g'      \
        -e 's/QUEUE_FLAG_DEAD/QUEUE_FLAG_DYING/g';                \
sed -i.tmp -e "s/QUEUE_FLAG_DYING$(printf \\t)*5/QUEUE_FLAG_DYING$(printf \\t)5/g" \
    include/linux/blkdev.h;                                       \
sed -i.tmp -e 's/ DEAD/ DYING/g' -e 's/dead queue/a dying queue/' \
    -e 's/Dead queue/A dying queue/' block/blk-core.c

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Chanho Min <chanho.min@lge.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-12-06 14:30:58 +01:00
Martin K. Petersen
5db44863b6 [SCSI] sd: Implement support for WRITE SAME
Implement support for WRITE SAME(10) and WRITE SAME(16) in the SCSI disk
driver.

 - We set the default maximum to 0xFFFF because there are several
   devices out there that only support two-byte block counts even with
   WRITE SAME(16). We only enable transfers bigger than 0xFFFF if the
   device explicitly reports MAXIMUM WRITE SAME LENGTH in the BLOCK
   LIMITS VPD.

 - max_write_same_blocks can be overriden per-device basis in sysfs.

 - The UNMAP discovery heuristics remain unchanged but the discard
   limits are tweaked to match the "real" WRITE SAME commands.

 - In the error handling logic we now distinguish between WRITE SAME
   with and without UNMAP set.

The discovery process heuristics are:

 - If the device reports a SCSI level of SPC-3 or greater we'll issue
   READ SUPPORTED OPERATION CODES to find out whether WRITE SAME(16) is
   supported. If that's the case we will use it.

 - If the device supports the block limits VPD and reports a MAXIMUM
   WRITE SAME LENGTH bigger than 0xFFFF we will use WRITE SAME(16).

 - Otherwise we will use WRITE SAME(10) unless the target LBA is beyond
   0xFFFFFFFF or the block count exceeds 0xFFFF.

 - no_write_same is set for ATA, FireWire and USB.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-11-13 22:45:42 -08:00
James Bottomley
fe709ed827 Merge SCSI misc branch into isci-for-3.6 tag 2012-10-02 08:55:12 +01:00
Vikas Chaudhary
0e58076b37 [SCSI] scsi_lib: Set the device state from transport-offline to running
FC and iSCSI class set SCSI devices to transport-offline state after
fast_io_fail/replacement_timeout has fired, but after relogin, function
scsi_internal_device_unblock() is not setting scsi device state to running.
Due to this the devices even after being relogged in remain offline.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-14 17:59:22 +01:00
Mike Snitzer
27c419739b [SCSI] scsi_lib: fix scsi_io_completion's SG_IO error propagation
The following v3.4-rc1 commit unmasked an existing bug in scsi_io_completion's
SG_IO error handling: 47ac56d [SCSI] scsi_error: classify some ILLEGAL_REQUEST
sense as a permanent TARGET_ERROR

Given that certain ILLEGAL_REQUEST are now properly categorized as
TARGET_ERROR the host_byte is being set (before host_byte wasn't ever
set for these ILLEGAL_REQUEST).

In scsi_io_completion, initialize req->errors with cmd->result _after_
the SG_IO block that calls __scsi_error_from_host_byte (which may
modify the host_byte).

Before this fix:

    cdb to send: 12 01 01 00 00 00
ioctl(3, SG_IO, {'S', SG_DXFER_NONE, cmd[6]=[12, 01, 01, 00, 00, 00],
    mx_sb_len=32, iovec_count=0, dxfer_len=0, timeout=20000, flags=0,
    status=02, masked_status=01, sb[19]=[70, 00, 05, 00, 00, 00, 00, 0b,
    00, 00, 00, 00, 24, 00, 00, 00, 00, 00, 00], host_status=0x10,
    driver_status=0x8, resid=0, duration=0, info=0x1}) = 0
SCSI Status: Check Condition

Sense Information:
sense buffer empty

After:

    cdb to send: 12 01 01 00 00 00
ioctl(3, SG_IO, {'S', SG_DXFER_NONE, cmd[6]=[12, 01, 01, 00, 00, 00],
    mx_sb_len=32, iovec_count=0, dxfer_len=0, timeout=20000, flags=0,
    status=02, masked_status=01, sb[19]=[70, 00, 05, 00, 00, 00, 00, 0b,
    00, 00, 00, 00, 24, 00, 00, 00, 00, 00, 00], host_status=0,
    driver_status=0x8, resid=0, duration=0, info=0x1}) = 0
SCSI Status: Check Condition

Sense Information:
 Fixed format, current;  Sense key: Illegal Request
 Additional sense: Invalid field in cdb
 Raw sense data (in hex):
        70 00 05 00 00 00 00 0b  00 00 00 00 24 00 00 00
        00 00 00

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Babu Moger <babu.moger@netapp.com>
Cc: stable@vger.kernel.org # 3.4
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-08-22 09:42:31 +04:00
Jeff Garzik
8407884dd9 Merge branch 'master' [vanilla Linus master] into libata-dev.git/upstream
Two bits were appended to the end of the bitfield
list in struct scsi_device.  Resolve that conflict
by including both bits.

Conflicts:
	include/scsi/scsi_device.h
2012-07-25 15:58:48 -04:00
Bart Van Assche
b485462aca [SCSI] Stop accepting SCSI requests before removing a device
Avoid that the code for requeueing SCSI requests triggers a
crash by making sure that that code isn't scheduled anymore
after a device has been removed.

Also, source code inspection of __scsi_remove_device() revealed
a race condition in this function: no new SCSI requests must be
accepted for a SCSI device after device removal started.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:41 +01:00
Bart Van Assche
84feb1664e [SCSI] Change return type of scsi_queue_insert() into void
The return value of scsi_queue_insert() is ignored by all its
callers, hence change the return type of this function into
void.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:41 +01:00
Bart Van Assche
940f5d47e2 [SCSI] Avoid dangling pointer in scsi_requeue_command()
When we call scsi_unprep_request() the command associated with the request
gets destroyed and therefore drops its reference on the device.  If this was
the only reference, the device may get released and we end up with a NULL
pointer deref when we call blk_requeue_request.

Reported-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>
[jejb: enhance commend and add commit log for stable]
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:40 +01:00
Bart Van Assche
67bd941300 [SCSI] Fix device removal NULL pointer dereference
Use blk_queue_dead() to test whether the queue is dead instead
of !sdev. Since scsi_prep_fn() may be invoked concurrently with
__scsi_remove_device(), keep the queuedata (sdev) pointer in
__scsi_remove_device(). This patch fixes a kernel oops that
can be triggered by USB device removal. See also
http://www.spinics.net/lists/linux-scsi/msg56254.html.

Other changes included in this patch:
- Swap the blk_cleanup_queue() and kfree() calls in
  scsi_host_dev_release() to make that code easier to grasp.
- Remove the queue dead check from scsi_run_queue() since the
  queue state can change anyway at any point in that function
  where the queue lock is not held.
- Remove the queue dead check from the start of scsi_request_fn()
  since it is redundant with the scsi_device_online() check.

Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:40 +01:00
Mike Christie
d075498c98 [SCSI] remove old comment from block/unblock functions
We do not hold the host lock when calling these functions,
so remove comment.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:23 +01:00
Mike Christie
5d9fb5cc1b [SCSI] core, classes, mpt2sas: have scsi_internal_device_unblock take new state
This has scsi_internal_device_unblock/scsi_target_unblock take
the new state to set the devices as an argument instead of
always setting to running. The patch also converts users of these
functions.

This allows the FC and iSCSI class to transition devices from blocked
to transport-offline, so that when fast_io_fail/replacement_timeout
has fired we do not set the devices back to running. Instead, we
set them to SDEV_TRANSPORT_OFFLINE.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:22 +01:00
Mike Christie
1b8d262061 [SCSI] add new SDEV_TRANSPORT_OFFLINE state
This patch adds a new state SDEV_TRANSPORT_OFFLINE. It will
be used by transport classes to offline devices for cases like
when the fast_io_fail/recovery_tmo fires. In those cases we
want all IO to fail, and we have not yet escalated to dev_loss_tmo
behavior where we are removing the devices.

Currently to handle this state, transport classes are setting
the scsi_device's state to running, setting their internal
session/port structs state to something that indicates failed,
and then failing IO from some transport check in the queuecommand.

The reason for the new value is so that users can distinguish
between a device failure that is a result of a transport problem
vs the wide range of errors that devices get offlined for
when a scsi command times out and we offline the devices there.
It also fixes the confusion as to why the transport class is
failing IO, but has set the device state from blocked to running.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:21 +01:00
Holger Macht
de50ada55b [SCSI] add wrapper to access and set scsi_bus_type in struct acpi_bus_type
For being able to bind ata devices against acpi devices, scsi_bus_type
needs to be set as bus in struct acpi_bus_type. So add wrapper to
scsi_lib to accomplish that.

Signed-off-by: Holger Macht <holger@homac.de>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2012-06-29 11:38:09 -04:00
Jun'ichi Nomura
b7e94a1686 [SCSI] Fix dm-multipath starvation when scsi host is busy
block congestion control doesn't have any concept of fairness across
multiple queues.  This means that if SCSI reports the host as busy in
the queue congestion control it can result in an unfair starvation
situation in dm-mp if there are multiple multipath devices on the same
host.  For example:
http://www.redhat.com/archives/dm-devel/2012-May/msg00123.html

The fix for this is to report only the sdev busy state (and ignore the
host busy state) in the block congestion control call back.
The host is still congested, but the SCSI subsystem will sort out the
congestion in a fair way because it knows the relation between the
queues and the host.

[jejb: fixed up trailing whitespace]
Reported-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Tested-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-23 09:34:17 +01:00
James Bottomley
e346933365 isci update for 3.5
1/ Rework remote-node-context (RNC) handling for proper management of
    the silicon state machine in error handling and hot-plug conditions.
    Further details below, suffice to say if the RNC is mismanaged the
    silicon state machines may lock up.
 
 2/ Refactor the initialization code to be reused for suspend/resume support
 
 3/ Miscellaneous bug fixes to address discovery issues and hardware
    compatibility.
 
 RNC rework details from Jeff Skirvin:
 
 In the controller, devices as they appear on a SAS domain (or
 direct-attached SATA devices) are represented by memory structures known
 as "Remote Node Contexts" (RNCs).  These structures are transferred from
 main memory to the controller using a set of register commands; these
 commands include setting up the context ("posting"), removing the
 context ("invalidating"), and commands to control the scheduling of
 commands and connections to that remote device ("suspensions" and
 "resumptions").  There is a similar path to control RNC scheduling from
 the protocol engine, which interprets the results of command and data
 transmission and reception.
 
 In general, the controller chooses among non-suspended RNCs to find one
 that has work requiring scheduling the transmission of command and data
 frames to a target.  Likewise, when a target tries to return data back
 to the initiator, the state of the RNC is used by the controller to
 determine how to treat the incoming request. As an example, if the RNC
 is in the state "TX/RX Suspended", incoming SSP connection requests from
 the target will be rejected by the controller hardware.  When an RNC is
 "TX Suspended", it will not be selected by the controller hardware to
 start outgoing command or data operations (with certain priority-based
 exceptions).
 
 As mentioned above, there are two sources for management of the RNC
 states: commands from driver software, and the result of transmission
 and reception conditions of commands and data signaled by the controller
 hardware.  As an example of the latter, if an outgoing SSP command ends
 with a OPEN_REJECT(BAD_DESTINATION) status, the RNC state will
 transition to the "TX Suspended" state, and this is signaled by the
 controller hardware in the status to the completion of the pending
 command as well as signaled in a controller hardware event.  Examples of
 the former are included in the patch changelogs.
 
 Driver software is required to suspend the RNC in a "TX/RX Suspended"
 condition before any outstanding commands can be terminated.  Failure to
 guarantee this can lead to a complete hardware hang condition.  Earlier
 versions of the driver software did not guarantee that an RNC was
 correctly managed before I/O termination, and so operated in an unsafe
 way.
 
 Further, the driver performed unnecessary contortions to preserve the
 remote device command state and so was more complicated than it needed
 to be.  A simplifying driver assumption is that once an I/O has entered
 the error handler path without having completed in the target, the
 requirement on the driver is that all use of the sas_task must end.
 Beyond that, recovery of operation is dependent on libsas and other
 components to reset, rediscover and reconfigure the device before normal
 operation can restart.  In the driver, this simplifying assumption meant
 that the RNC management could be reduced to entry into the suspended
 state, terminating the targeted I/O request, and resuming the RNC as
 needed for device-specific management such as an SSP Abort Task or LUN
 Reset Management request.
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Merge tag 'isci-for-3.5' into misc

isci update for 3.5

1/ Rework remote-node-context (RNC) handling for proper management of
   the silicon state machine in error handling and hot-plug conditions.
   Further details below, suffice to say if the RNC is mismanaged the
   silicon state machines may lock up.

2/ Refactor the initialization code to be reused for suspend/resume support

3/ Miscellaneous bug fixes to address discovery issues and hardware
   compatibility.

RNC rework details from Jeff Skirvin:

In the controller, devices as they appear on a SAS domain (or
direct-attached SATA devices) are represented by memory structures known
as "Remote Node Contexts" (RNCs).  These structures are transferred from
main memory to the controller using a set of register commands; these
commands include setting up the context ("posting"), removing the
context ("invalidating"), and commands to control the scheduling of
commands and connections to that remote device ("suspensions" and
"resumptions").  There is a similar path to control RNC scheduling from
the protocol engine, which interprets the results of command and data
transmission and reception.

In general, the controller chooses among non-suspended RNCs to find one
that has work requiring scheduling the transmission of command and data
frames to a target.  Likewise, when a target tries to return data back
to the initiator, the state of the RNC is used by the controller to
determine how to treat the incoming request. As an example, if the RNC
is in the state "TX/RX Suspended", incoming SSP connection requests from
the target will be rejected by the controller hardware.  When an RNC is
"TX Suspended", it will not be selected by the controller hardware to
start outgoing command or data operations (with certain priority-based
exceptions).

As mentioned above, there are two sources for management of the RNC
states: commands from driver software, and the result of transmission
and reception conditions of commands and data signaled by the controller
hardware.  As an example of the latter, if an outgoing SSP command ends
with a OPEN_REJECT(BAD_DESTINATION) status, the RNC state will
transition to the "TX Suspended" state, and this is signaled by the
controller hardware in the status to the completion of the pending
command as well as signaled in a controller hardware event.  Examples of
the former are included in the patch changelogs.

Driver software is required to suspend the RNC in a "TX/RX Suspended"
condition before any outstanding commands can be terminated.  Failure to
guarantee this can lead to a complete hardware hang condition.  Earlier
versions of the driver software did not guarantee that an RNC was
correctly managed before I/O termination, and so operated in an unsafe
way.

Further, the driver performed unnecessary contortions to preserve the
remote device command state and so was more complicated than it needed
to be.  A simplifying driver assumption is that once an I/O has entered
the error handler path without having completed in the target, the
requirement on the driver is that all use of the sas_task must end.
Beyond that, recovery of operation is dependent on libsas and other
components to reset, rediscover and reconfigure the device before normal
operation can restart.  In the driver, this simplifying assumption meant
that the RNC management could be reduced to entry into the suspended
state, terminating the targeted I/O request, and resuming the RNC as
needed for device-specific management such as an SSP Abort Task or LUN
Reset Management request.
2012-05-21 12:17:30 +01:00
Dan Williams
a7a20d1039 [SCSI] sd: limit the scope of the async probe domain
sd injects and synchronizes probe work on the global kernel-wide domain.
This runs into conflict with PM that wants to perform resume actions in
async context:

[  494.237079] INFO: task kworker/u:3:554 blocked for more than 120 seconds.
[  494.294396] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  494.360809] kworker/u:3     D 0000000000000000     0   554      2 0x00000000
[  494.420739]  ffff88012e4d3af0 0000000000000046 ffff88013200c160 ffff88012e4d3fd8
[  494.484392]  ffff88012e4d3fd8 0000000000012500 ffff8801394ea0b0 ffff88013200c160
[  494.548038]  ffff88012e4d3ae0 00000000000001e3 ffffffff81a249e0 ffff8801321c5398
[  494.611685] Call Trace:
[  494.632649]  [<ffffffff8149dd25>] schedule+0x5a/0x5c
[  494.674687]  [<ffffffff8104b968>] async_synchronize_cookie_domain+0xb6/0x112
[  494.734177]  [<ffffffff810461ff>] ? __init_waitqueue_head+0x50/0x50
[  494.787134]  [<ffffffff8131a224>] ? scsi_remove_target+0x48/0x48
[  494.837900]  [<ffffffff8104b9d9>] async_synchronize_cookie+0x15/0x17
[  494.891567]  [<ffffffff8104ba49>] async_synchronize_full+0x54/0x70  <-- here we wait for async contexts to complete
[  494.943783]  [<ffffffff8104b9f5>] ? async_synchronize_full_domain+0x1a/0x1a
[  495.002547]  [<ffffffffa00114b1>] sd_remove+0x2c/0xa2 [sd_mod]
[  495.051861]  [<ffffffff812fe94f>] __device_release_driver+0x86/0xcf
[  495.104807]  [<ffffffff812fe9bd>] device_release_driver+0x25/0x32  <-- here we take device_lock()

[  853.511341] INFO: task kworker/u:4:549 blocked for more than 120 seconds.
[  853.568693] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  853.635119] kworker/u:4     D ffff88013097b5d0     0   549      2 0x00000000
[  853.695129]  ffff880132773c40 0000000000000046 ffff880130790000 ffff880132773fd8
[  853.758990]  ffff880132773fd8 0000000000012500 ffff88013288a0b0 ffff880130790000
[  853.822796]  0000000000000246 0000000000000040 ffff88013097b5c8 ffff880130790000
[  853.886633] Call Trace:
[  853.907631]  [<ffffffff8149dd25>] schedule+0x5a/0x5c
[  853.949670]  [<ffffffff8149cc44>] __mutex_lock_common+0x220/0x351
[  854.001225]  [<ffffffff81304bd7>] ? device_resume+0x58/0x1c4
[  854.049082]  [<ffffffff81304bd7>] ? device_resume+0x58/0x1c4
[  854.097011]  [<ffffffff8149ce48>] mutex_lock_nested+0x2f/0x36   <-- here we wait for device_lock()
[  854.145591]  [<ffffffff81304bd7>] device_resume+0x58/0x1c4
[  854.192066]  [<ffffffff81304d61>] async_resume+0x1e/0x45
[  854.237019]  [<ffffffff8104bc93>] async_run_entry_fn+0xc6/0x173  <-- ...while running in async context

Provide a 'scsi_sd_probe_domain' so that async probe actions actions can
be flushed without regard for the state of PM, and allow for the resume
path to handle devices that have transitioned from SDEV_QUIESCE to
SDEV_DEL prior to resume.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
[alan: uplevel scsi_sd_probe_domain, clarify scsi_device_resume]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[jejb: remove unneeded config guards in include file]
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-17 09:10:46 +01:00
Lin Ming
6f381fa344 [SCSI] scsi_lib: use correct DMA device in __scsi_alloc_queue
Currently, __scsi_alloc_queue uses SCSI host's parent device
as DMA device to set segment boundary. But the parent device may not
refer to the DMA device. For example, for ATA disk, SCSI host's parent
device now refers to ATA port.

Since commit d139b9b([SCSI] scsi_lib_dma: fix bug with dma maps on
nested scsi objects), a new field Scsi_Host->dma_dev was introduced
to refer to the real DMA device.

Use ->dma_dev in __scsi_alloc_queue to correctly set segment
boundary.

Bug report: http://marc.info/?l=linux-ide&m=133177818318187&w=2

Reported-and-tested-by: Jörg Sommer <joerg@alea.gnuu.de>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-22 18:56:18 +01:00
Linus Torvalds
424a6f6ef9 SCSI updates on 20120319
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

SCSI updates from James Bottomley:
 "The update includes the usual assortment of driver updates (lpfc,
  qla2xxx, qla4xxx, bfa, bnx2fc, bnx2i, isci, fcoe, hpsa) plus a huge
  amount of infrastructure work in the SAS library and transport class
  as well as an iSCSI update.  There's also a new SCSI based virtio
  driver."

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (177 commits)
  [SCSI] qla4xxx: Update driver version to 5.02.00-k15
  [SCSI] qla4xxx: trivial cleanup
  [SCSI] qla4xxx: Fix sparse warning
  [SCSI] qla4xxx: Add support for multiple session per host.
  [SCSI] qla4xxx: Export CHAP index as sysfs attribute
  [SCSI] scsi_transport: Export CHAP index as sysfs attribute
  [SCSI] qla4xxx: Add support to display CHAP list and delete CHAP entry
  [SCSI] iscsi_transport: Add support to display CHAP list and delete CHAP entry
  [SCSI] pm8001: fix endian issue with code optimization.
  [SCSI] pm8001: Fix possible racing condition.
  [SCSI] pm8001: Fix bogus interrupt state flag issue.
  [SCSI] ipr: update PCI ID definitions for new adapters
  [SCSI] qla2xxx: handle default case in qla2x00_request_firmware()
  [SCSI] isci: improvements in driver unloading routine
  [SCSI] isci: improve phy event warnings
  [SCSI] isci: debug, provide state-enum-to-string conversions
  [SCSI] scsi_transport_sas: 'enable' phys on reset
  [SCSI] libsas: don't recover end devices attached to disabled phys
  [SCSI] libsas: fixup target_port_protocols for expanders that don't report sata
  [SCSI] libsas: set attached device type and target protocols for local phys
  ...
2012-03-22 12:55:29 -07:00
Cong Wang
77dfce076c scsi: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:19 +08:00
Martin K. Petersen
66a651aa7a [SCSI] Ensure discard failure gets treated as a target problem
The error reported up the stack for a discard failure did not clearly
indicate that the command was processed and subsequently failed by the
target device.

Return -EREMOTEIO so multipathing does not classify this condition as a
path failure.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 09:38:01 -06:00
Moger, Babu
2082ebc45a [SCSI] fix the new host byte settings (DID_TARGET_FAILURE and DID_NEXUS_FAILURE)
This patch fixes the host byte settings DID_TARGET_FAILURE and
DID_NEXUS_FAILURE.  The function __scsi_error_from_host_byte, tries to reset
the host byte to DID_OK. But that does not happen because of the OR operation.

Here is the flow.

scsi_softirq_done-> scsi_decide_disposition -> __scsi_error_from_host_byte

Let's take an example with DID_NEXUS_FAILURE. In scsi_decide_disposition,
result will be set as DID_NEXUS_FAILURE (=0x11). Then in
__scsi_error_from_host_byte, when we do OR with DID_OK.  Purpose is to reset
it back to DID_OK. But that does not happen.  This patch fixes this issue.

Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 08:08:59 -06:00
Shaohua Li
466c08c71a [SCSI] don't change sdev starvation list order without request dispatched
The sdev is deleted from starved list and then try to dispatch from this
device. It's quite possible the sdev can't eventually dispatch a request,
then the sdev will be in starved list tail. This isn't fair.
There are two cases here:
1. unplug path. scsi_request_fn() calls to scsi_target_queue_ready(), then
the dev is removed from starved list, but quite possible host queue isn't
ready, the dev is moved to starved list without dispatching any request.
2. scsi_run_queue path. It deletes the dev from starved list first (both
global and local starved lists), then handles the dev. Then we could have
the same process like case 1.

This patch fixes the first case. Case 2 isn't fixed, because there is a
rare case scsi_run_queue finds host isn't busy but scsi_request_fn finds
host is busy (other CPU is faster to get host queue depth). Not deleting
the dev from starved list in scsi_run_queue will keep scsi_run_queue
looping (though this is very rare case, because host will become busy).
Fortunately fixing case 1 already gives big improvement for starvation in
my test. In a 12 disk JBOD setup, running file creation under EXT4, this
gives 12% more throughput.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-16 11:54:04 +04:00
Hannes Reinecke
745718132c [SCSI] Silencing 'killing requests for dead queue'
When we tear down a device we try to flush all outstanding
commands in scsi_free_queue(). However the check in
scsi_request_fn() is imperfect as it only signals that
we _might start_ aborting commands, not that we've actually
aborted some.
So move the printk inside the scsi_kill_request function,
this will also give us a hint about which commands are aborted.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-11-09 12:07:07 -06:00
Linus Torvalds
32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Paul Gortmaker
09703660ed scsi: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required
For the basic SCSI infrastructure files that are exporting symbols
but not modules themselves, add in the basic export.h header file
to allow the exports.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:23 -04:00
Bart Van Assche
3308511c93 [SCSI] Make scsi_free_queue() kill pending SCSI commands
Make sure that SCSI device removal via scsi_remove_host() does finish
all pending SCSI commands. Currently that's not the case and hence
removal of a SCSI host during I/O can cause a deadlock. See also
"blkdev_issue_discard() hangs forever if underlying storage device is
removed" (http://bugzilla.kernel.org/show_bug.cgi?id=40472). See also
http://lkml.org/lkml/2011/8/27/6.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: <stable@kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-30 13:20:28 +04:00
James Smart
573e591353 [SCSI] scsi_lib: pause between error retries
During cable pull tests on our 16G FC adapter, we are seeing errors,
typically reads to close targets, which fail due to CRC or framing
errors caused by the cable being pull (return status DID_ERROR).
The adapter detects the error on one of the first frames received,
marks the FC exchange as dead (further frames go to bit bucket) and
signals the host of the error. This action is so quick, and coupled
with fast host CPUs, creates a scenario in which the midlayer sees
the failure and retries the io almost immediately. We've seen link
traces with the retry on the link while the original i/o is still
being processed by the target. We're also seeing the time window
for the "link to pull-apart" and the physical interface to report
disconnected to be in the few millisecond range. Which means, we're
encountering scenarios where the full retry count is exhausted
(all with error) by the midlayer before the link disconnect state
is detected.

We looked at 8G FC behavior and occasionally see the same behavior,
but as the link was slower, it rarely could exhaust all retries
before the link reported disconnect.

What is needed is a slight delay between io retries due to DID_ERROR
to cover this error.  It is inappropriate to put this delay in the
driver, as the error is indistinguishable from other link-related errors,
nor does the driver track whether the io is a retry or not. This is also
easier than tracking between-io-error bursts that are seen in this
scenario.

The patch below updates the retry path so that it inserts a delay as
if the target was busy.  The busy delay is on the order of 6ms. This
delay is sufficient to ensure the link down condition is reported
before the retry count is exhausted (at most 1 retry is seen).

Signed-off-by: Alex Iannicelli <alex.iannicelli@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-27 14:06:01 +04:00
James Bottomley
bfe159a512 [SCSI] fix crash in scsi_dispatch_cmd()
USB surprise removal of sr is triggering an oops in
scsi_dispatch_command().  What seems to be happening is that USB is
hanging on to a queue reference until the last close of the upper
device, so the crash is caused by surprise remove of a mounted CD
followed by attempted unmount.

The problem is that USB doesn't issue its final commands as part of
the SCSI teardown path, but on last close when the block queue is long
gone.  The long term fix is probably to make sr do the teardown in the
same way as sd (so remove all the lower bits on ejection, but keep the
upper disk alive until last close of user space).  However, the
current oops can be simply fixed by not allowing any commands to be
sent to a dead queue.

Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-21 14:21:18 -07:00
Linus Torvalds
a2b9c1f620 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: don't delay blk_run_queue_async
  scsi: remove performance regression due to async queue run
  blk-throttle: Use task_subsys_state() to determine a task's blkio_cgroup
  block: rescan partitions on invalidated devices on -ENOMEDIA too
  cdrom: always check_disk_change() on open
  block: unexport DISK_EVENT_MEDIA_CHANGE for legacy/fringe drivers
2011-05-18 06:49:02 -07:00
Jens Axboe
9937a5e2f3 scsi: remove performance regression due to async queue run
Commit c21e6beb removed our queue request_fn re-enter
protection, and defaulted to always running the queues from
kblockd to be safe. This was a known potential slow down,
but should be safe.

Unfortunately this is causing big performance regressions for
some, so we need to improve this logic. Looking into the details
of the re-enter, the real issue is on requeue of requests.

Requeue of requests upon seeing a BUSY condition from the device
ends up re-running the queue, causing traces like this:

scsi_request_fn()
        scsi_dispatch_cmd()
                scsi_queue_insert()
                        __scsi_queue_insert()
                                scsi_run_queue()
					scsi_request_fn()
						...

potentially causing the issue we want to avoid. So special
case the requeue re-run of the queue, but improve it to offload
the entire run of local queue and starved queue from a single
workqueue callback. This is a lot better than potentially
kicking off a workqueue run for each device seen.

This also fixes the issue of the local device going into recursion,
since the above mentioned commit never moved that queue run out
of line.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-17 11:04:44 +02:00
James Bottomley
c055f5b261 [SCSI] fix oops in scsi_run_queue()
The recent commit closing the race window in device teardown:

commit 86cbfb5607
Author: James Bottomley <James.Bottomley@suse.de>
Date:   Fri Apr 22 10:39:59 2011 -0500

    [SCSI] put stricter guards on queue dead checks

is causing a potential NULL deref in scsi_run_queue() because the
q->queuedata may already be NULL by the time this function is called.
Since we shouldn't be running a queue that is being torn down, simply
add a NULL check in scsi_run_queue() to forestall this.

Tested-by: Jim Schutt <jaschut@sandia.gov>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-05-03 15:30:00 -05:00
Jens Axboe
c21e6beba8 block: get rid of QUEUE_FLAG_REENTER
We are currently using this flag to check whether it's safe
to call into ->request_fn(). If it is set, we punt to kblockd.
But we get a lot of false positives and excessive punts to
kblockd, which hurts performance.

The only real abuser of this infrastructure is SCSI. So export
the async queue run and convert SCSI over to use that. There's
room for improvement in that SCSI need not always use the async
call, but this fixes our performance issue and they can fix that
up in due time.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-19 13:32:46 +02:00
Christoph Hellwig
24ecfbe27f block: add blk_run_queue_async
Instead of overloading __blk_run_queue to force an offload to kblockd
add a new blk_run_queue_async helper to do it explicitly.  I've kept
the blk_queue_stopped check for now, but I suspect it's not needed
as the check we do when the workqueue items runs should be enough.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-18 11:41:33 +02:00
Linus Torvalds
6c51038900 Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
  Documentation/iostats.txt: bit-size reference etc.
  cfq-iosched: removing unnecessary think time checking
  cfq-iosched: Don't clear queue stats when preempt.
  blk-throttle: Reset group slice when limits are changed
  blk-cgroup: Only give unaccounted_time under debug
  cfq-iosched: Don't set active queue in preempt
  block: fix non-atomic access to genhd inflight structures
  block: attempt to merge with existing requests on plug flush
  block: NULL dereference on error path in __blkdev_get()
  cfq-iosched: Don't update group weights when on service tree
  fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away
  block: Require subsystems to explicitly allocate bio_set integrity mempool
  jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
  fs: make fsync_buffers_list() plug
  mm: make generic_writepages() use plugging
  blk-cgroup: Add unaccounted time to timeslice_used.
  block: fixup plugging stubs for !CONFIG_BLOCK
  block: remove obsolete comments for blkdev_issue_zeroout.
  blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.
  ...

Fix up conflicts in fs/{aio.c,super.c}
2011-03-24 10:16:26 -07:00
Linus Torvalds
c55d267de2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (170 commits)
  [SCSI] scsi_dh_rdac: Add MD36xxf into device list
  [SCSI] scsi_debug: add consecutive medium errors
  [SCSI] libsas: fix ata list corruption issue
  [SCSI] hpsa: export resettable host attribute
  [SCSI] hpsa: move device attributes to avoid forward declarations
  [SCSI] scsi_debug: Logical Block Provisioning (SBC3r26)
  [SCSI] sd: Logical Block Provisioning update
  [SCSI] Include protection operation in SCSI command trace
  [SCSI] hpsa: fix incorrect PCI IDs and add two new ones (2nd try)
  [SCSI] target: Fix volume size misreporting for volumes > 2TB
  [SCSI] bnx2fc: Broadcom FCoE offload driver
  [SCSI] fcoe: fix broken fcoe interface reset
  [SCSI] fcoe: precedence bug in fcoe_filter_frames()
  [SCSI] libfcoe: Remove stale fcoe-netdev entries
  [SCSI] libfcoe: Move FCOE_MTU definition from fcoe.h to libfcoe.h
  [SCSI] libfc: introduce __fc_fill_fc_hdr that accepts fc_hdr as an argument
  [SCSI] fcoe, libfc: initialize EM anchors list and then update npiv EMs
  [SCSI] Revert "[SCSI] libfc: fix exchange being deleted when the abort itself is timed out"
  [SCSI] libfc: Fixing a memory leak when destroying an interface
  [SCSI] megaraid_sas: Version and Changelog update
  ...

Fix up trivial conflicts due to whitespace differences in
drivers/scsi/libsas/{sas_ata.c,sas_scsi_host.c}
2011-03-17 17:54:40 -07:00
Martin K. Petersen
c98a0eb0e9 [SCSI] sd: Logical Block Provisioning update
SBC3r26 contains many changes to the Logical Block Provisioning
interfaces (formerly known as Thin Provisioning ditto). This patch
implements support for both the old and new schemes using the same
heuristic as before (whether the LBP VPD page is present).

The new code also allows the provisioning mode (i.e. choice of command)
to be overridden on a per-device basis via sysfs. Two additional modes
are supported in this version:

 - WRITE SAME(10) with the UNMAP bit set

 - WRITE SAME(10) without the UNMAP bit set. This allows us to support
   devices that predate the TP/LBP enhancements in SBC3 and which work
   by way zero-detection

Switching between modes has been consolidated in a helper function that
also updates the block layer topology according to the limitations of
the chosen command.

I experimented with trying WRITE SAME(16) if UNMAP fails, WRITE SAME(10)
if WRITE SAME(16) fails, etc. but found several devices that got
cranky. So for now we'll disable discard if one of the commands
fail. The user still has the option of selecting a different mode in
sysfs.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-14 18:37:34 -05:00
Martin K. Petersen
72f7d322fd [SCSI] Include protection operation in SCSI command trace
When debugging DIF/DIX it is very helpful to be able to see which DIX
operation is associated with the scsi_cmnd. Include the protection op in
the SCSI command trace.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-14 18:36:02 -05:00
Jens Axboe
4c63f5646e Merge branch 'for-2.6.39/stack-plug' into for-2.6.39/core
Conflicts:
	block/blk-core.c
	block/blk-flush.c
	drivers/md/raid1.c
	drivers/md/raid10.c
	drivers/md/raid5.c
	fs/nilfs2/btnode.c
	fs/nilfs2/mdt.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:58:35 +01:00
Jens Axboe
a488e74976 scsi: convert to blk_delay_queue()
It was always abuse to reuse the plugging infrastructure for this,
convert it to the (new) real API for delaying queueing a bit. A
default delay of 3 msec is defined, to match the previous
behaviour.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:45:54 +01:00
Tejun Heo
1654e7411a block: add @force_kblockd to __blk_run_queue()
__blk_run_queue() automatically either calls q->request_fn() directly
or schedules kblockd depending on whether the function is recursed.
blk-flush implementation needs to be able to explicitly choose
kblockd.  Add @force_kblockd.

All the current users are converted to specify %false for the
parameter and this patch doesn't introduce any behavior change.

stable: This is prerequisite for fixing ide oops caused by the new
        blk-flush implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-02 08:48:05 -05:00
Hannes Reinecke
63583cca74 [SCSI] Add detailed SCSI I/O errors
Instead of just passing 'EIO' for any I/O error we should be
notifying the upper layers with more details about the cause
of this error.

Update the possible I/O errors to:

- ENOLINK: Link failure between host and target
- EIO: Retryable I/O error
- EREMOTEIO: Non-retryable I/O error
- EBADE: I/O error restricted to the I_T_L nexus

'Retryable' in this context means that an I/O error _might_ be
restricted to the I_T_L nexus (vulgo: path), so retrying on another
nexus / path might succeed.

'Non-retryable' in general refers to a target failure, so this
error will always be generated regardless of the I_T_L nexus
it was send on.

I/O errors restricted to the I_T_L nexus might be retried
on another nexus / path, but they should _not_ be queued
if no paths are available.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 10:33:08 -06:00
Linus Torvalds
275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Linus Torvalds
da40d036fd Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (147 commits)
  [SCSI] arcmsr: fix write to device check
  [SCSI] lpfc: lower stack use in lpfc_fc_frame_check
  [SCSI] eliminate an unnecessary local variable from scsi_remove_target()
  [SCSI] libiscsi: use bh locking instead of irq with session lock
  [SCSI] libiscsi: do not take host lock in queuecommand
  [SCSI] be2iscsi: fix null ptr when accessing task hdr
  [SCSI] be2iscsi: fix gfp use in alloc_pdu
  [SCSI] libiscsi: add more informative failure message during iscsi scsi eh
  [SCSI] gdth: Add missing call to gdth_ioctl_free
  [SCSI] bfa: remove unused defintions and misc cleanups
  [SCSI] bfa: remove inactive functions
  [SCSI] bfa: replace bfa_assert with WARN_ON
  [SCSI] qla2xxx: Use sg_next to fetch next sg element while walking sg list.
  [SCSI] qla2xxx: Fix to avoid recursive lock failure during BSG timeout.
  [SCSI] qla2xxx: Remove code to not reset ISP82xx on failure.
  [SCSI] qla2xxx: Display mailbox register 4 during 8012 AEN for ISP82XX parts.
  [SCSI] qla2xxx: Don't perform a BIG_HAMMER if Get-ID (0x20) mailbox command fails on CNAs.
  [SCSI] qla2xxx: Remove redundant module parameter permission bits
  [SCSI] qla2xxx: Add sysfs node for displaying board temperature.
  [SCSI] qla2xxx: Code cleanup to remove unwanted comments and code.
  ...
2011-01-07 12:47:02 -08:00
Hillf Danton
fd01a6632d [SCSI] fix the return value of scsi_target_queue_read()
It seems that zero should be returned if scsi_target_is_busy(starget) is
true, no matter if sdev is on the starved list.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-21 12:37:28 -06:00
Linus Torvalds
7f8635cc9e Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cciss: fix cciss_revalidate panic
  block: max hardware sectors limit wrapper
  block: Deprecate QUEUE_FLAG_CLUSTER and use queue_limits instead
  blk-throttle: Correct the placement of smp_rmb()
  blk-throttle: Trim/adjust slice_end once a bio has been dispatched
  block: check for proper length of iov entries earlier in blk_rq_map_user_iov()
  drbd: fix for spin_lock_irqsave in endio callback
  drbd: don't recvmsg with zero length
2010-12-20 09:19:46 -08:00
Martin K. Petersen
e692cb668f block: Deprecate QUEUE_FLAG_CLUSTER and use queue_limits instead
When stacking devices, a request_queue is not always available. This
forced us to have a no_cluster flag in the queue_limits that could be
used as a carrier until the request_queue had been set up for a
metadevice.

There were several problems with that approach. First of all it was up
to the stacking device to remember to set queue flag after stacking had
completed. Also, the queue flag and the queue limits had to be kept in
sync at all times. We got that wrong, which could lead to us issuing
commands that went beyond the max scatterlist limit set by the driver.

The proper fix is to avoid having two flags for tracking the same thing.
We deprecate QUEUE_FLAG_CLUSTER and use the queue limit directly in the
block layer merging functions. The queue_limit 'no_cluster' is turned
into 'cluster' to avoid double negatives and to ease stacking.
Clustering defaults to being enabled as before. The queue flag logic is
removed from the stacking function, and explicitly setting the cluster
flag is no longer necessary in DM and MD.

Reported-by: Ed Lin <ed.lin@promise.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-17 08:35:53 +01:00
Tejun Heo
9f8a2c23c6 scsi: replace sr_test_unit_ready() with scsi_test_unit_ready()
The usage of TUR has been confusing involving several different
commits updating different parts over time.  Currently, the only
differences between scsi_test_unit_ready() and sr_test_unit_ready()
are,

* scsi_test_unit_ready() also sets sdev->changed on NOT_READY.

* scsi_test_unit_ready() returns 0 if TUR ended with UNIT_ATTENTION or
  NOT_READY.

Due to the above two differences, sr is using its own
sr_test_unit_ready(), but sd - the sole user of the above extra
handling - doesn't even need them.

Where scsi_test_unit_ready() is used in sd_media_changed(), the code
is looking for device ready w/ media present state which is true iff
TUR succeeds w/o sense data or UA, and when the device is not ready
for whatever reason sd_media_changed() explicitly marks media as
missing so there's no reason to set sdev->changed automatically from
scsi_test_unit_ready() on NOT_READY.

Drop both special handlings from scsi_test_unit_ready(), which makes
it equivalant to sr_test_unit_ready(), and replace
sr_test_unit_ready() with scsi_test_unit_ready().  Also, drop the
unnecessary explicit NOT_READY check from sd_media_changed().
Checking return value is enough for testing device readiness.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-16 17:53:39 +01:00
James Bottomley
459dbf72e4 [SCSI] Eliminate error handler overload of the SCSI serial number
The error handler is using the test cmd->serial_number == 0 in the
abort routines to signal that the command to be aborted has already
completed normally.  This design was to close a race window in the
original error handler where a command could go through the normal
completion routines after it timed out but before error handling was
started.

Mike Anderson pointed out that when we converted our timeout and
softirq completions, we picked up atomicity here because the block
layer now mediates this with the REQ_ATOM_COMPLETE flag and guarantees
that *either* the command times out or our done routine is called, but
ensures we can't get both occurring.  That makes the serial number
zero check redundant and it can be removed.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-09 09:41:16 -06:00
Mike Christie
986fe6c7f5 [SCSI] Fix regressions in scsi_internal_device_block
Deleting a SCSI device on a blocked fc_remote_port (before
fast_io_fail_tmo fires) results in a hanging thread:

  STACK:
  0 schedule+1108 [0x5cac48]
  1 schedule_timeout+528 [0x5cb7fc]
  2 wait_for_common+266 [0x5ca6be]
  3 blk_execute_rq+160 [0x354054]
  4 scsi_execute+324 [0x3b7ef4]
  5 scsi_execute_req+162 [0x3b80ca]
  6 sd_sync_cache+138 [0x3cf662]
  7 sd_shutdown+138 [0x3cf91a]
  8 sd_remove+112 [0x3cfe4c]
  9 __device_release_driver+124 [0x3a08b8]
10 device_release_driver+60 [0x3a0a5c]
11 bus_remove_device+266 [0x39fa76]
12 device_del+340 [0x39d818]
13 __scsi_remove_device+204 [0x3bcc48]
14 scsi_remove_device+66 [0x3bcc8e]
15 sysfs_schedule_callback_work+50 [0x260d66]
16 worker_thread+622 [0x162326]
17 kthread+160 [0x1680b0]
18 kernel_thread_starter+6 [0x10aaea]

During the delete, the SCSI device is in moved to SDEV_CANCEL.  When
the FC transport class later calls scsi_target_unblock, this has no
effect, since scsi_internal_device_unblock ignores SCSI devics in this
state.

It looks like all these are regressions caused by:
5c10e63c94
[SCSI] limit state transitions in scsi_internal_device_unblock

Fix by rejecting offline and cancel in the state transition.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
[jejb: Original patch by Christof Schmitt, modified by Mike Christie]
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-10-25 09:48:32 -05:00
Linus Torvalds
e9dd2b6837 Merge branch 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block: (39 commits)
  cfq-iosched: Fix a gcc 4.5 warning and put some comments
  block: Turn bvec_k{un,}map_irq() into static inline functions
  block: fix accounting bug on cross partition merges
  block: Make the integrity mapped property a bio flag
  block: Fix double free in blk_integrity_unregister
  block: Ensure physical block size is unsigned int
  blkio-throttle: Fix possible multiplication overflow in iops calculations
  blkio-throttle: limit max iops value to UINT_MAX
  blkio-throttle: There is no need to convert jiffies to milli seconds
  blkio-throttle: Fix link failure failure on i386
  blkio: Recalculate the throttled bio dispatch time upon throttle limit change
  blkio: Add root group to td->tg_list
  blkio: deletion of a cgroup was causes oops
  blkio: Do not export throttle files if CONFIG_BLK_DEV_THROTTLING=n
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: revert bad fix for memory hotplug causing bounces
  Fix compile error in blk-exec.c for !CONFIG_DETECT_HUNG_TASK
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: Prevent hang_check firing during long I/O
  cfq: improve fsync performance for small files
  ...

Fix up trivial conflicts due to __rcu sparse annotation in include/linux/genhd.h
2010-10-22 17:00:32 -07:00
Martin K. Petersen
13f05c8d8e block/scsi: Provide a limit on the number of integrity segments
Some controllers have a hardware limit on the number of protection
information scatter-gather list segments they can handle.

Introduce a max_integrity_segments limit in the block layer and provide
a new scsi_host_template setting that allows HBA drivers to provide a
value suitable for the hardware.

Add support for honoring the integrity segment limit when merging both
bios and requests.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
2010-09-10 20:50:10 +02:00
James Bottomley
3a5c19c23d [SCSI] fix use-after-free in scsi_init_io()
we're using a pointer through a freed command to reset the request,
which has shown up as an oops with slab poisoning:

Reported-by: Tejun Heo <tj@kernel.org>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-09-09 09:58:18 -05:00
Bartlomiej Zolnierkiewicz
d6e9fb46cd scsi: remove superfluous NULL pointer check from scsi_kill_request()
Dan's list included:

drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced in initializer 'cmd'
drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced before check 'cmd'

We dereference cmd (and possible OOPS if cmd == NULL) before starting the
request so just remove the superfluous debugging code altogether.

[ bart: the potential NULL pointer dereference was finally fixed in
  (much later than mine) commit 03b1470 but my patch is still valid ]

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Eugene Teo <eteo@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:00 -07:00
FUJITA Tomonori
610a63498f scsi: fix discard page leak
We leak a page allocated for discard on some error conditions
(e.g. scsi_prep_state_check returns BLKPREP_DEFER in
scsi_setup_blk_pc_cmnd).

We unprep on requests that weren't prepped in the error path of
scsi_init_io. It makes the error path to clean up scsi commands messy.

Let's strictly apply the rule that we can't unprep on a request that
wasn't prepped.

Calling just scsi_put_command() in the error path of scsi_init_io() is
enough. We don't set REQ_DONTPREP yet.

scsi_setup_discard_cmnd can safely free a page on the error case with
the above rule.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:28 +02:00
James Bottomley
28018c242a block: implement an unprep function corresponding directly to prep
Reviewed-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:23:47 +02:00
Christoph Hellwig
33659ebbae block: remove wrappers for request type/flags
Remove all the trivial wrappers for the cmd_type and cmd_flags fields in
struct requests.  This allows much easier grepping for different request
types instead of unwinding through macros.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:17:56 +02:00
Linus Torvalds
b1bf936840 Merge branch 'for-2.6.34' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.34' of git://git.kernel.dk/linux-2.6-block: (38 commits)
  block: don't access jiffies when initialising io_context
  cfq: remove 8 bytes of padding from cfq_rb_root on 64 bit builds
  block: fix for "Consolidate phys_segment and hw_segment limits"
  cfq-iosched: quantum check tweak
  blktrace: perform cleanup after setup error
  blkdev: fix merge_bvec_fn return value checks
  cfq-iosched: requests "in flight" vs "in driver" clarification
  cciss: Fix problem with scatter gather elements in the scsi half of the driver
  cciss: eliminate unnecessary pointer use in cciss scsi code
  cciss: do not use void pointer for scsi hba data
  cciss: factor out scatter gather chain block mapping code
  cciss: fix scatter gather chain block dma direction kludge
  cciss: simplify scatter gather code
  cciss: factor out scatter gather chain block allocation and freeing
  cciss: detect bad alignment of scsi commands at build time
  cciss: clarify command list padding calculation
  cfq-iosched: rethink seeky detection for SSDs
  cfq-iosched: rework seeky detection
  block: remove padding from io_context on 64bit builds
  block: Consolidate phys_segment and hw_segment limits
  ...
2010-03-01 09:00:29 -08:00
Martin K. Petersen
8a78362c4e block: Consolidate phys_segment and hw_segment limits
Except for SCSI no device drivers distinguish between physical and
hardware segment limits.  Consolidate the two into a single segment
limit.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-26 13:58:08 +01:00
Martin K. Petersen
086fa5ff08 block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectors
The block layer calling convention is blk_queue_<limit name>.
blk_queue_max_sectors predates this practice, leading to some confusion.
Rename the function to appropriately reflect that its intended use is to
set max_hw_sectors.

Also introduce a temporary wrapper for backwards compability.  This can
be removed after the merge window is closed.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-26 13:58:08 +01:00
Douglas Gilbert
e7efe5932b [SCSI] skip sense logging for some ATA PASS-THROUGH cdbs
Further to the lsml thread titled:
"does scsi_io_completion need to dump sense data for ata pass through (ck_cond =
1) ?"

This is a patch to skip logging when the sense data is
associated with a SENSE_KEY of "RECOVERED_ERROR" and the
additional sense code is "ATA PASS-THROUGH INFORMATION
AVAILABLE". This only occurs with the SAT ATA PASS-THROUGH
commands when CK_COND=1 (in the cdb). It indicates that
the sense data contains ATA registers.

Smartmontools uses such commands on ATA disks connected via
SAT. Periodic checks such as those done by smartd cause
nuisance entries into logs that are:
    - neither errors nor warnings
    - pointless unless the cdb that caused them are also logged

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-01-18 10:48:16 -06:00
Boaz Harrosh
63c43b0ec1 [SCSI] scsi_lib: Fix bug in completion of bidi commands
Because of the terrible structuring of scsi-bidi-commands
it breaks some of the life time rules of a scsi-command.
It is now not allowed to free up the block-request before
cleanup and partial deallocation of the scsi-command. (Which
is not so for none bidi commands)

The right fix to this problem would be to make bidi command
a first citizen by allocating a scsi_sdb pointer at scsi command
just like cmd->prot_sdb. The bidi sdb should be allocated/deallocated
as part of the get/put_command (Again like the prot_sdb) and the
current decoupling of scsi_cmnd and blk-request should be kept.

For now make sure scsi_release_buffers() is called before the
call to blk_end_request_all() which might cause the suicide of
the block requests. At best the leak of bidi buffers, at worse
a crash, as there is a race between the existence of the bidi_request
and the free of the associated bidi_sdb.

The reason this was never hit before is because only OSD has the potential
of doing asynchronous bidi commands. (So does bsg but it is never used)
And OSD clients just happen to do all their bidi commands synchronously, up
until recently.

CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-01-17 12:16:18 -06:00
Martin K. Petersen
d8705f11d8 [SCSI] Correctly handle thin provisioning write error
A thin provisioned device may temporarily be out of sufficient
allocation units to fulfill a write request.  In that case it will
return a space allocation in progress error.  Wait a bit and retry the
write.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-10 08:54:15 -06:00
Jiri Slaby
03b147083a [SCSI] scsi_lib: fix potential NULL dereference
Stanse found a potential NULL dereference in scsi_kill_request.

Instead of triggering BUG() in 'if (unlikely(cmd == NULL))' branch,
the kernel will Oops earlier on cmd dereference.

Move the dereferences after the if.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:51 -06:00
Mike Christie
ad63082626 [SCSI] fix propogation of integrity errors
When the Integrity check is done in scsi_io_completion it will
set error to -EILSEQ. However, at this point error is no longer
used, and blk_end_request_err has -EIO hardcoded.

It looks like there was just porting mistake with this patch
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=3e695f89c5debb735e4ff051e9e58d8fb4e95110
and we meant to send error upwards, so this patch changes the hard
coded EIO to the error variable.

I have only boot tested this patch.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-10-29 13:03:27 -04:00
Linus Torvalds
355bbd8cb8 Merge branch 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block: (29 commits)
  block: use blkdev_issue_discard in blk_ioctl_discard
  Make DISCARD_BARRIER and DISCARD_NOBARRIER writes instead of reads
  block: don't assume device has a request list backing in nr_requests store
  block: Optimal I/O limit wrapper
  cfq: choose a new next_req when a request is dispatched
  Seperate read and write statistics of in_flight requests
  aoe: end barrier bios with EOPNOTSUPP
  block: trace bio queueing trial only when it occurs
  block: enable rq CPU completion affinity by default
  cfq: fix the log message after dispatched a request
  block: use printk_once
  cciss: memory leak in cciss_init_one()
  splice: update mtime and atime on files
  block: make blk_iopoll_prep_sched() follow normal 0/1 return convention
  cfq-iosched: get rid of must_alloc flag
  block: use interrupts disabled version of raise_softirq_irqoff()
  block: fix comment in blk-iopoll.c
  block: adjust default budget for blk-iopoll
  block: fix long lines in block/blk-iopoll.c
  block: add blk-iopoll, a NAPI like approach for block devices
  ...
2009-09-14 17:55:15 -07:00
Tejun Heo
da6c5c720c scsi,block: update SCSI to handle mixed merge failures
Update scsi_io_completion() such that it only fails requests till the
next error boundary and retry the leftover.  This enables block layer
to merge requests with different failfast settings and still behave
correctly on errors.  Allow merge of requests of different failfast
settings.

As SCSI is currently the only subsystem which follows failfast status,
there's no need to worry about other block drivers for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Niel Lambrechts <niel.lambrechts@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-11 14:33:30 +02:00
Martin K. Petersen
002b1eb2c0 [SCSI] Print failed commands
When a request fails we print the sense data but not the actual command
that failed.  Add a printout of the operation + CDB for failed commands.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-22 17:51:51 -05:00
Hannes Reinecke
b391277a56 sd, sr: fix Driver 'sd' needs updating message
If a SCSI ULD driver sets blk_queue_prep_rq(), it should clean it
up itself on remove(), and not from the bus callbacks. This
removes the need to hook into bus->remove(), which should not
be used at the same time as driver->remove().

[jejb: fix sdkp initialisation problem due to mismerge]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-21 12:01:27 -05:00
James Bottomley
82681a318f [SCSI] Merge branch 'linus'
Conflicts:
	drivers/message/fusion/mptsas.c

fixed up conflict between req->data_len accessors and mptsas driver updates.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-06-12 10:02:03 -05:00
Takahiro Yasui
5c10e63c94 [SCSI] limit state transitions in scsi_internal_device_unblock
scsi timeout on two or more devices may cause extremely long execution
time for user applications because SDEV_OFFLINE state is changed to
SDEV_RUNNING state during scsi error recovery procedures triggered by
a bus reset or a host reset of scsi LLD, and scsi timeout can happens
on the same devices many times.

This happens because scsi_internal_device_unblock() changes device's
state to SDEV_RUNNING even if a device in other states than SDEV_BLOCK,
while the following two transitions are required in this function.

  SDEV_BLOCK -> SDEV_RUNNING
  SDEV_CREATED_BLOCK -> SDEV_CREATED

Otherwise, it returns -EINVAL.

Signed-off-by: Takahiro Yasui <tyasui@redhat.com>
[matthew@wil.cx: supplied rewritten base for patch]
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-05-23 15:44:05 -05:00
Jens Axboe
e4b636366c Merge branch 'master' into for-2.6.31
Conflicts:
	drivers/block/hd.c
	drivers/block/mg_disk.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 20:25:34 +02:00
Boaz Harrosh
ac36552a52 scsi_lib: remove unused variable
The last request completion cleanup in scsi_lib left an unused
this_count variable in scsi_io_completion().
(It was used before in a code segment that now uses blk_end_request_all())

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 19:54:09 +02:00
Tejun Heo
e458824f9d scsi: fix resid_len mis-conversion in scsi_end_request()
Commit c3a4d78c58 introduced
rq->data_len and converted residual count users to it.  While
converting, it mistakenly converted scsi_end_request() to finish
requests with residual count when it wants to do is fully complete the
request.  Fix it by using blk_end_request_all() instead.

This bug was spotted by Boaz Harrosh.

Signed-off-by: Tejun Heo <tj@kernel.org>
Spotted-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-12 08:49:32 +02:00
FUJITA Tomonori
e6bb7a96c2 scsi: simplify the bidi completion
Let's use blk_end_request_all() instead of blk_end_bidi_request().

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 11:06:47 +02:00
Tejun Heo
9934c8c045 block: implement and enforce request peek/start/fetch
Till now block layer allowed two separate modes of request execution.
A request is always acquired from the request queue via
elv_next_request().  After that, drivers are free to either dequeue it
or process it without dequeueing.  Dequeue allows elv_next_request()
to return the next request so that multiple requests can be in flight.

Executing requests without dequeueing has its merits mostly in
allowing drivers for simpler devices which can't do sg to deal with
segments only without considering request boundary.  However, the
benefit this brings is dubious and declining while the cost of the API
ambiguity is increasing.  Segment based drivers are usually for very
old or limited devices and as converting to dequeueing model isn't
difficult, it doesn't justify the API overhead it puts on block layer
and its more modern users.

Previous patches converted all block low level drivers to dequeueing
model.  This patch completes the API transition by...

* renaming elv_next_request() to blk_peek_request()

* renaming blkdev_dequeue_request() to blk_start_request()

* adding blk_fetch_request() which is combination of peek and start

* disallowing completion of queued (not started) requests

* applying new API to all LLDs

Renamings are for consistency and to break out of tree code so that
it's apparent that out of tree drivers need updating.

[ Impact: block request issue API cleanup, no functional change ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: unsik Kim <donari75@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Laurent Vivier <Laurent@lvivier.info>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:52:18 +02:00
Tejun Heo
1011c1b9f2 block: blk_rq_[cur_]_{sectors|bytes}() usage cleanup
With the previous changes, the followings are now guaranteed for all
requests in any valid state.

* blk_rq_sectors() == blk_rq_bytes() >> 9
* blk_rq_cur_sectors() == blk_rq_cur_bytes() >> 9

Clean up accessor usages.  Notable changes are

* nbd,i2o_block: end_all used instead of explicit byte count
* scsi_lib: unnecessary conditional on request type removed

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:55 +02:00
Tejun Heo
b079041030 block: cleanup rq->data_len usages
With recent unification of fields, it's now guaranteed that
rq->data_len always equals blk_rq_bytes().  Convert all non-IDE direct
users to accessors.  IDE will be converted in a separate patch.

Boaz: spotted incorrect data_len/resid_len conversion in osd.

[ Impact: convert direct rq->data_len usages to blk_rq_bytes() ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:55 +02:00
Tejun Heo
83096ebf12 block: convert to pos and nr_sectors accessors
With recent cleanups, there is no place where low level driver
directly manipulates request fields.  This means that the 'hard'
request fields always equal the !hard fields.  Convert all
rq->sectors, nr_sectors and current_nr_sectors references to
accessors.

While at it, drop superflous blk_rq_pos() < 0 test in swim.c.

[ Impact: use pos and nr_sectors accessors ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Mike Miller <mike.miller@hp.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: unsik Kim <donari75@gmail.com>
Cc: Laurent Vivier <Laurent@lvivier.info>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:54 +02:00
Tejun Heo
5b93629b45 block: implement blk_rq_pos/[cur_]sectors() and convert obvious ones
Implement accessors - blk_rq_pos(), blk_rq_sectors() and
blk_rq_cur_sectors() which return rq->hard_sector, rq->hard_nr_sectors
and rq->hard_cur_sectors respectively and convert direct references of
the said fields to the accessors.

This is in preparation of request data length handling cleanup.

Geert	: suggested adding const to struct request * parameter to accessors
Sergei	: spotted error in patch description

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Ackec-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00
Tejun Heo
c3a4d78c58 block: add rq->resid_len
rq->data_len served two purposes - the length of data buffer on issue
and the residual count on completion.  This duality creates some
headaches.

First of all, block layer and low level drivers can't really determine
what rq->data_len contains while a request is executing.  It could be
the total request length or it coulde be anything else one of the
lower layers is using to keep track of residual count.  This
complicates things because blk_rq_bytes() and thus
[__]blk_end_request_all() relies on rq->data_len for PC commands.
Drivers which want to report residual count should first cache the
total request length, update rq->data_len and then complete the
request with the cached data length.

Secondly, it makes requests default to reporting full residual count,
ie. reporting that no data transfer occurred.  The residual count is
an exception not the norm; however, the driver should clear
rq->data_len to zero to signify the normal cases while leaving it
alone means no data transfer occurred at all.  This reverse default
behavior complicates code unnecessarily and renders block PC on some
drivers (ide-tape/floppy) unuseable.

This patch adds rq->resid_len which is used only for residual count.

While at it, remove now unnecessasry blk_rq_bytes() caching in
ide_pc_intr() as rq->data_len is not changed anymore.

Boaz	: spotted missing conversion in osd
Sergei	: spotted too early conversion to blk_rq_bytes() in ide-tape

[ Impact: cleanup residual count handling, report 0 resid by default ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00
Tejun Heo
731ec497e5 block: kill rq->data
Now that all block request data transfer is done via bio, rq->data
isn't used.  Kill it.

While at it, make the roles of rq->special and buffer clear.

[ Impact: drop now unncessary field from struct request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Boaz Harrosh <bharrosh@panasas.com>
2009-04-28 07:37:36 +02:00
Tejun Heo
40cbbb781d block: implement and use [__]blk_end_request_all()
There are many [__]blk_end_request() call sites which call it with
full request length and expect full completion.  Many of them ensure
that the request actually completes by doing BUG_ON() the return
value, which is awkward and error-prone.

This patch adds [__]blk_end_request_all() which takes @rq and @error
and fully completes the request.  BUG_ON() is added to to ensure that
this actually happens.

Most conversions are simple but there are a few noteworthy ones.

* cdrom/viocd: viocd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/block/dasd: dasd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/char/tape_block: tapeblock_end_request() replaced with direct
  calls to blk_end_request_all().

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-28 07:37:35 +02:00
Mike Christie
b4efdd586b [SCSI] fix q->lock not held warning when target is busy
We cannot call blk_plug_device from scsi_target_queue_ready
because the q lock is not held. And we do not need to call
it from there because when we return 0, the scsi_request_fn
not_ready handling will plug the queue for us if needed.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-27 09:48:10 -05:00
James Bottomley
a9bddd7463 [SCSI] fix recovered error handling
We have a problem with recovered error handling in that any command
which goes down as BLOCK_PC but which returns a sense code of RECOVERED
ERROR gets completed with -EIO.  For actual SG_IO commands, this doesn't
matter at all, since the error return code gets dropped in favour of
req->errors which contain the SCSI completion code.

However, if this command is part of the block system, then it will pay
attention to the returned error code.  In particularly if a SYNCHRONIZE
CACHE from a barrier command completes with RECOVERED ERROR, the
resulting -EIO on the barrier causes block to error the request and
return it to the filesystem.  Fix this by converting the -EIO for
recovered error to zero, plus remove the printing of this from sd and sr
so the message isn't double printed.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:22:55 -05:00
FUJITA Tomonori
f078727b25 [SCSI] remove scsi_req_map_sg
No one uses scsi_execute_async with data transfer now. We can remove
scsi_req_map_sg.

Only scsi_eh_lock_door uses scsi_execute_async. scsi_eh_lock_door
doesn't handle sense and the callback. So we can remove
scsi_io_context too.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-12 12:58:10 -05:00
James Bottomley
126c098296 [SCSI] fix ABORTED_COMMAND looping forever problem
Instead of terminating after five retries, commands terminated by
ABORTED_COMMAND sense are retrying forever.  The problem was
introduced by:

commit b60af5b0ad
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon Nov 3 15:56:47 2008 -0500

    [SCSI] simplify scsi_io_completion()

Which introduced an error whereby ABORTED_COMMAND now gets erroneously
retried in scsi_io_completion.  Fix this by returning the behaviour
back to the default no retry.

Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-02-21 20:29:38 -06:00
James Bottomley
79ed242972 [SCSI] scsi_lib: fix DID_RESET status problems
Andrew Vaszquez said:
> There's a problem that is causing commands returned by the LLD with
> a DID_RESET status to be reissued with cleared cmd->sdb data which
> in our tests are manifesting in firmware detected overruns.  Here's
> a snippet of a READ_10 scsi_cmnd upon completion by the storage

The problem is caused by:

commit b60af5b0ad
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon Nov 3 15:56:47 2008 -0500

    [SCSI] simplify scsi_io_completion()

Because scsi_release_buffers() is called before commands that go
through the ACTION_RETRY and ACTION_DELAYED_RETRY legs are requeued.
However, they're not re-prepared, so nothing ever reallocates the
buffer resources to them.  Fix this by releasing the buffers only if
we're not going to go down these legs (but scsi_release_buffers() on
all legs including two in scsi_end_request(); this latter needs a
special version __scsi_release_buffers() because the final one can be
called after the request has been freed, so the bidi test in
scsi_release_buffers(), which touches the request has to be skipped).

Reported-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-07 15:15:44 -06:00
Martin K. Petersen
3e695f89c5 [SCSI] Fix error handling for DIF/DIX
patch

commit b60af5b0ad
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon Nov 3 15:56:47 2008 -0500

    [SCSI] simplify scsi_io_completion()

broke DIX error handling.  Also, we are now using EILSEQ to indicate
integrity errors to the upper layers (as opposed to regular EIO
failures).  This allows filesystems to inspect buffers and decide
whether to retry the I/O.  Update scsi_io_completion() accordingly.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-05 09:02:28 -06:00
James Bottomley
4f5299ac4e [SCSI] scsi_lib: don't decrement busy counters when inserting commands
A bug was introduced by

commit b60af5b0ad
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Mon Nov 3 15:56:47 2008 -0500

    [SCSI] simplify scsi_io_completion()
 
because the simplification uses scsi_queue_insert().  The problem with
this function is that it expects to be called from the completion path
while the command is still outstanding, so it decrements the device
and host busy counts to do the requeue.  The problem is that
scsi_io_completion() is a path executed well after these counts have
*already* been decremented, leading to a double decrement if the
command goes down any error path leading to ACTION_DELAYED_RETRY.

The fix is to allow a private function __scsi_queue_insert() with a
flag to say whether the busy counters should be decremented.  This is
made static to scsi_lib.c to discourage other use.

Reported-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-05 08:54:11 -06:00
Alan Stern
3dbf6a5404 [SCSI] Fix uninitialized variable error in scsi_io_completion
This patch (as1191) adds a missing "default" case in
scsi_io_completion(), thereby fixing an "uninitialized variable"
error.  It also adds a missing newline to a log entry.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-01-02 10:57:41 -06:00
FUJITA Tomonori
f4f4e47e4a [SCSI] add residual argument to scsi_execute and scsi_execute_req
scsi_execute() and scsi_execute_req() discard the residual length
information. Some callers need it. This adds residual argument
(optional) to scsi_execute and scsi_execute_req.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:24 -06:00
Alan Stern
b60af5b0ad [SCSI] simplify scsi_io_completion()
This patch (as1142b) consolidates a lot of repetitious code in
scsi_io_completion().  It also fixes a few comments.  Most
importantly, however, it clearly distinguishes among the three sorts
of retries that can be done when a command fails to complete:

	Unprepare the request and resubmit it, so that a new
	command will be created for it.

	Requeue the request directly so that it will be retried
	immediately using the same command.

	Requeue the request so that it will be retried following
	a short delay.

	Complete the remainder of the request with an I/O error.

[jejb: Updates
     1. For several error conditions, we would now print the sense twice
        in slightly different ways, so unify the location of sense
        printing.
     2. I added more descriptions to actual failure conditions for
        better debugging
     3. according to spec, ABORTED_COMMAND is supposed to be retried
        (except on DIF failure).  Our old behaviour of erroring it looks
        to be a bug.
     4. I'd prefer not to default initialise the action variable because
        that ensures that every leg of the error handler has an
        associated action and the compiler will warn if someone later
        accidentally misses one or removes one.
]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:18 -06:00
James Bottomley
02bd3499a3 [SCSI] scsi_lib: only call scsi_unprep_request() under queue lock
It's called under that lock everywhere else and it does alter the
request state, so it should be.

This one occurance in scsi_requeue_command() could open a window where
req->special is set to NULL while the requests is going through either
timeout or completion processing leading to NULL pointer derefs of the
sort complained of in bugzillas 12020 and 12195.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-13 14:31:03 -06:00
Mike Christie
2a3a59e5c9 [SCSI] Fix hang in starved list processing
Close possible infinite loop with interrupts off when devices are
added back to the starved list.

Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=11898

Reported-by: <alex.shi@intel.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-11-16 08:13:58 -06:00
Kiyoshi Ueda
6c5121b78b [SCSI] export busy state via q->lld_busy_fn()
This patch implements q->lld_busy_fn() for scsi mid layer to export
its busy state for request stacking drivers.

For efficiency, no lock is taken to check the busy state of
shost/starget/sdev, since the returned value is not guaranteed and
may be changed after request stacking drivers call the function,
regardless of taking lock or not.

When scsi can't dispatch I/Os anymore and needs to kill I/Os
(e.g. !sdev), scsi needs to return 'not busy'.
Otherwise, request stacking drivers may hold requests forever.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:16 -05:00
Kiyoshi Ueda
9d11251709 [SCSI] refactor sdev/starget/shost busy checking
This patch refactors the busy checking codes of scsi_device,
Scsi_Host and scsi_target.  There should be no functional change.

This is a preparation for another patch which exports scsi's busy
state to the block layer for request stacking drivers.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:16 -05:00
James Bottomley
32c356d76d [SCSI] fix removable device inability to detect disk changes
On Tue, 12 Aug 2008 15:08:14 +0200
Giuliano Pochini <pochini@shiny.it> wrote:

> Fujitsu magneto-optical drive, Adaptec 29160 and
> Linux Jay 2.6.26 #7 SMP Sun Aug 10 18:34:22 CEST 2008 ppc 7455, altivec supported PowerMac3,6 GNU/Linux
>
> When I insert a disk and I mount it, scsi_test_unit_ready() is called and
> the do-while loop gets sshdr->sense_key == UNIT_ATTENTION in the first
> cycle and 0 in the second one. So the if below misses the UNIT_ATTENTION
> and sdev->changed = 1 is not executed. At this point bad things can
> happen... I'm not sure how to fix this. Any clue ?

The problem is essentially caused by us eating UNIT_ATTENTION
conditions in scsi_test_unit_ready().  Fix by updating the ->changed
flag when this happens if the media is removable.

[pochini@shiny.it: updates to tidy up patch]
Signed-off-by: Giuliano Pochini <pochini@shiny.it>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:41:16 -05:00
Mike Christie
4a27446f3e [SCSI] modify scsi to handle new fail fast flags.
This checks the errors the scsi-ml determined were retryable
and returns if we should fast fail it based on the request
fail fast flags.

Without the patch, drivers like lpfc, qla2xxx and fcoe would return
DID_ERROR for what it determines is a temporary communication problem.
There is no loss of connectivity at that time and the driver thinks
that it would be fast to retry at the driver level. SCSI-ml will however
sees fast fail on the request and DID_ERROR and will fast fail the io.
This will then cause dm-multipath to fail the path and possibley switch
target controllers when we should be retrying at the scsi layer.

We also were fast failing device errors to dm multiapth when
unless the scsi_dh modules think otherwis we want to retry at
the scsi layer because multipath can only retry the IO like scsi
should have done. multipath is a little dumber though because it
does not what the error was for and assumes that it should fail
the paths.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:52 -04:00
Mike Christie
f0c0a376d0 [SCSI] Add helper code so transport classes/driver can control queueing (v3)
SCSI-ml manages the queueing limits for the device and host, but
does not do so at the target level. However something something similar
can come in userful when a driver is transitioning a transport object to
the the blocked state, becuase at that time we do not want to queue
io and we do not want the queuecommand to be called again.

The patch adds code similar to the exisiting SCSI_ML_*BUSY handlers.
You can now return SCSI_MLQUEUE_TARGET_BUSY when we hit
a transport level queueing issue like the hw cannot allocate some
resource at the iscsi session/connection level, or the target has temporarily
closed or shrunk the queueing window, or if we are transitioning
to the blocked state.

bnx2i, when they rework their firmware according to netdev
developers requests, will also need to be able to limit queueing at this
level. bnx2i will hook into libiscsi, but will allocate a scsi host per
netdevice/hba, so unlike pure software iscsi/iser which is allocating
a host per session, it cannot set the scsi_host->can_queue and return
SCSI_MLQUEUE_HOST_BUSY to reflect queueing limits on the transport.

The iscsi class/driver can also set a scsi_target->can_queue value which
reflects the max commands the driver/class can support. For iscsi this
reflects the number of commands we can support for each session due to
session/connection hw limits, driver limits, and to also reflect the
session/targets's queueing window.

Changes:
v1 - initial patch.
v2 - Fix scsi_run_queue handling of multiple blocked targets.
Previously we would break from the main loop if a device was added back on
the starved list. We now run over the list and check if any target is
blocked.
v3 - Rediff for scsi-misc.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:46 -04:00
Linus Torvalds
ef5bef357c Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (37 commits)
  [SCSI] zfcp: fix double dbf id usage
  [SCSI] zfcp: wait on SCSI work to be finished before proceeding with init dev
  [SCSI] zfcp: fix erp list usage without using locks
  [SCSI] zfcp: prevent fc_remote_port_delete calls for unregistered rport
  [SCSI] zfcp: fix deadlock caused by shared work queue tasks
  [SCSI] zfcp: put threshold data in hba trace
  [SCSI] zfcp: Simplify zfcp data structures
  [SCSI] zfcp: Simplify get_adapter_by_busid
  [SCSI] zfcp: remove all typedefs and replace them with standards
  [SCSI] zfcp: attach and release SAN nameserver port on demand
  [SCSI] zfcp: remove unused references, declarations and flags
  [SCSI] zfcp: Update message with input from review
  [SCSI] zfcp: add queue_full sysfs attribute
  [SCSI] scsi_dh: suppress comparison warning
  [SCSI] scsi_dh: add Dell product information into rdac device handler
  [SCSI] qla2xxx: remove the unused SCSI_QLOGIC_FC_FIRMWARE option
  [SCSI] qla2xxx: fix printk format warnings
  [SCSI] qla2xxx: Update version number to 8.02.01-k8.
  [SCSI] qla2xxx: Ignore payload reserved-bits during RSCN processing.
  [SCSI] qla2xxx: Additional residual-count corrections during UNDERRUN handling.
  ...
2008-10-10 10:53:26 -07:00
Jens Axboe
242f9dcb8b block: unify request timeout handling
Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

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

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
James Bottomley
6f4267e3bd [SCSI] Update the SCSI state model to allow blocking in the created state
Brian King <brking@linux.vnet.ibm.com> reported that fibre channel
devices can oops during scanning if their ports block (because the
device goes from CREATED -> BLOCK -> RUNNING rather than CREATED ->
BLOCK -> CREATED).

Fix this by adding a new state: CREATED_BLOCK which can only transition
back to CREATED and disallow the CREATED -> BLOCK transition.  Now both
the created and blocked states that the mid-layer recognises can include
CREATED_BLOCK.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-03 11:46:13 -05:00
James Bottomley
44ea91c597 [SCSI] Fix hang with split requests
Sometimes, particularly for USB devices with the last sector bug,
requests get completed in chunks.  There's a bug in this in that if
one of the chunks gets an error, we complete that chunk with an error
but never move on to the remaining ones, leading to the request
hanging (because it's not fully completed).

Fix this by completing all remaining chunks if an error is encountered.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-09-23 12:29:01 -07:00
Harvey Harrison
cadbd4a5e3 [SCSI] replace __FUNCTION__ with __func__
[jejb: fixed up a ton of missed conversions.

 All of you are on notice this has happened, driver trees will now
 need to be rebased]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: SCSI List <linux-scsi@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-27 10:31:49 -04:00
Mike Christie
6bd522f6a2 [SCSI] scsi_lib: use blk_rq_tagged in scsi_request_fn
I goofed and did not see the macro for checking if a request is tagged.
This patch has us use blk_rq_tagged instead of digging into the req->tag.

Patch was made over scsi-misc.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-26 15:14:59 -04:00
Martin K. Petersen
511e44f42e [SCSI] Do not retry a request whose data integrity check failed
If initiator or target reject the I/O due to DIF errors there is no
point in retrying.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-26 15:14:55 -04:00
Martin K. Petersen
7027ad72a6 [SCSI] Support devices with protection information
Implement support for DMA of protection information for devices that
are data integrity capable.

 - Add support for mapping an extra scatter-gather list containing
   the protection information.

 - Allocate protection scsi_data_buffer if host is DIX (integrity DMA)
   capable.

 - Accessor function for checking whether a device has protection
   enabled.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-26 15:14:55 -04:00
Mike Christie
ecefe8a975 [SCSI] fix shared tag map tag allocation
When drivers use a shared tag map we can end up with more requests
than tags, because the tag map is shost->can_queue tags and there
can be sdevs * sdev->queue_depth requests. In scsi_request_fn
if tag allocation fails we just drop down to just dequeueing the
tag without a tag. The problem is that drivers using the shared tag
map rely on a valid tag always being set, because it will use the
tag number to lookup commands later.

This patch has us check if we got a valid tag when the host lock
is held right before we check if the host queue is ready. We do the
check here because to allocate the tag we need the q lock, but
if the tag is bad we want to add the device/q onto the starved list
which requires the host lock.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-26 15:14:50 -04:00
Linus Torvalds
89a93f2f48 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (102 commits)
  [SCSI] scsi_dh: fix kconfig related build errors
  [SCSI] sym53c8xx: Fix bogus sym_que_entry re-implementation of container_of
  [SCSI] scsi_cmnd.h: remove double inclusion of linux/blkdev.h
  [SCSI] make struct scsi_{host,target}_type static
  [SCSI] fix locking in host use of blk_plug_device()
  [SCSI] zfcp: Cleanup external header file
  [SCSI] zfcp: Cleanup code in zfcp_erp.c
  [SCSI] zfcp: zfcp_fsf cleanup.
  [SCSI] zfcp: consolidate sysfs things into one file.
  [SCSI] zfcp: Cleanup of code in zfcp_aux.c
  [SCSI] zfcp: Cleanup of code in zfcp_scsi.c
  [SCSI] zfcp: Move status accessors from zfcp to SCSI include file.
  [SCSI] zfcp: Small QDIO cleanups
  [SCSI] zfcp: Adapter reopen for large number of unsolicited status
  [SCSI] zfcp: Fix error checking for ELS ADISC requests
  [SCSI] zfcp: wait until adapter is finished with ERP during auto-port
  [SCSI] ibmvfc: IBM Power Virtual Fibre Channel Adapter Client Driver
  [SCSI] sg: Add target reset support
  [SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC
  [SCSI] sd: Move scsi_disk() accessor function to sd.h
  ...
2008-07-15 18:58:04 -07:00
James Bottomley
2476b4d042 [SCSI] fix locking in host use of blk_plug_device()
scsi_lib.c:scsi_host_queue_ready() plugs the device with incorrect
locking.  It should actually have the queue lock held, but it's
holding the host lock.  Fix this by eliminating the call.  The host
ready has no need to plug the queue because if it returns 0 in
scsi_request_function control transfers to not_ready which acquires
the queue lock and plugs the device if its at zero depth.

Reported-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:36 -05:00
Martin K. Petersen
6362abd3e0 [SCSI] Rename scsi_bidi_sdb_cache
The data integrity changes need to dynamically allocate
scsi_data_buffers too.  Rename scsi_bidi_sdb_cache for clarity.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:24 -05:00
Alan Stern
bdb2b8cab4 [SCSI] erase invalid data returned by device
This patch (as1108) fixes a problem that can occur with certain USB
mass-storage devices: They return invalid data together with a residue
indicating that the data should be ignored.  Rather than leave the
invalid data in a transfer buffer, where it can get misinterpreted,
the patch clears the invalid portion of the buffer.

This solves a problem (wrong write-protect setting detected) reported
by Maciej Rutecki and Peter Teoh.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Peter Teoh <htmldeveloper@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-06 11:33:08 -05:00
Chandra Seetharaman
a6a8d9f87e [SCSI] scsi_dh: add infrastructure for SCSI Device Handlers
Some of the storage devices (that can be accessed through multiple paths),
do need some special handling for
	1. Activating the passive path of the storage access.
	2. Decode and handle the special sense codes returned by the devices.
	3. Handle the I/Os being sent to the passive path, especially
           during the device probe time.
when accessed through multiple paths.

As of today this special device handling is done at the dm-multipath
layer using dm-handlers. That works well for (1); for (2) to be handled
at dm layer, scsi sense information need to be exported from SCSI to dm-layer,
which is not very attractive; (3) cannot be done at all at the dm layer.

Device handler has been moved to SCSI mainly to handle (2) and (3) properly.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:40 -05:00
Linus Torvalds
d626e3bf72 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
  [SCSI] aic94xx: fix section mismatch
  [SCSI] u14-34f: Fix 32bit only problem
  [SCSI] dpt_i2o: sysfs code
  [SCSI] dpt_i2o: 64 bit support
  [SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent
  [SCSI] dpt_i2o: use standard __init / __exit code
  [SCSI] megaraid_sas: fix suspend/resume sections
  [SCSI] aacraid: Add Power Management support
  [SCSI] aacraid: Fix jbod operations scan issues
  [SCSI] aacraid: Fix warning about macro side-effects
  [SCSI] add support for variable length extended commands
  [SCSI] Let scsi_cmnd->cmnd use request->cmd buffer
  [SCSI] bsg: add large command support
  [SCSI] aacraid: Fix down_interruptible() to check the return value correctly
  [SCSI] megaraid_sas; Update the Version and Changelog
  [SCSI] ibmvscsi: Handle non SCSI error status
  [SCSI] bug fix for free list handling
  [SCSI] ipr: Rename ipr's state scsi host attribute to prevent collisions
  [SCSI] megaraid_mbox: fix Dell CERC firmware problem
2008-05-02 13:52:35 -07:00
Boaz Harrosh
db4742dd8f [SCSI] add support for variable length extended commands
Add support for variable-length, extended, and vendor specific
CDBs to scsi-ml. It is now possible for initiators and ULD's
to issue these types of commands. LLDs need not change much.
All they need is to raise the .max_cmd_len to the longest command
they support (see iscsi patch).

- clean-up some code paths that did not expect commands to be
  larger than 16, and change cmd_len members' type to short as
  char is not enough.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-05-02 11:33:25 -05:00
Boaz Harrosh
64a87b244b [SCSI] Let scsi_cmnd->cmnd use request->cmd buffer
- struct scsi_cmnd had a 16 bytes command buffer of its own.
   This is an unnecessary duplication and copy of request's
   cmd. It is probably left overs from the time that scsi_cmnd
   could function without a request attached. So clean that up.

 - Once above is done, few places, apart from scsi-ml, needed
   adjustments due to changing the data type of scsi_cmnd->cmnd.

 - Lots of drivers still use MAX_COMMAND_SIZE. So I have left
   that #define but equate it to BLK_MAX_CDB. The way I see it
   and is reflected in the patch below is.
   MAX_COMMAND_SIZE - means: The longest fixed-length (*) SCSI CDB
                      as per the SCSI standard and is not related
                      to the implementation.
   BLK_MAX_CDB.     - The allocated space at the request level

 - I have audit all ISA drivers and made sure none use ->cmnd in a DMA
   Operation. Same audit was done by Andi Kleen.

(*)fixed-length here means commands that their size can be determined
   by their opcode and the CDB does not carry a length specifier, (unlike
   the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
   true and the SCSI standard also defines extended commands and
   vendor specific commands that can be bigger than 16 bytes. The kernel
   will support these using the same infrastructure used for VARLEN CDB's.
   So in effect MAX_COMMAND_SIZE means the maximum size command
   scsi-ml supports without specifying a cmd_len by ULD's

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-05-02 10:18:22 -05:00
Nick Piggin
75ad23bc0f block: make queue flags non-atomic
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:33 +02:00
James Bottomley
fa8e36c39b [SCSI] fix barrier failure issue
Currently, if the barrier command fails, the error return isn't seen
by the block layer and it proceeds on regardless.  The problem is that
SCSI always returns no error for REQ_TYPE_BLOCK_PC ... it expects the
submitter to pick the errors out of req->errors, which the block
barrier functions don't do.

Since it appears that the way SG_IO and scsi_execute_request() work
they discard the block error return and always use req->errors, the
best fix for this is to have the SCSI layer return an error to block
if one actually occurred (this also allows us to filter out spurious
errors, like deferred sense).

This patch is a bug fix that will need backporting to stable, but it's
also quite a big change and in need of testing, so we'll incubate in
the main kernel tree and backport at the -rc2 or so stage if no
problems turn up.

Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-07 12:19:10 -05:00
Adrian Bunk
8c5e03d3cf [SCSI] make scsi_end_bidi_request() static
This patch makes the needlessly global scsi_end_bidi_request() static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-07 12:19:08 -05:00
Kay Sievers
4d1566ed21 [SCSI] fix media change events for polled devices
Commit:
  a341cd0f (SCSI: add asynchronous event notification API)
breaks:
  285e9670 (sr,sd: send media state change modification events)
by introducing an event filter, which is removed here, to make
events, we are depending on, happen again.

Fix this by removing the event filter.  It's pretty much broken at the
moment, since a user can't set it (the attribute being read only).  A
proper fix will be to make the event discriminator distinguish between
AN and Polled media change events.

Cc: David Zeuthen <david@fubar.dk>
Cc: kristen accardi <kaccardi@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-03-19 11:51:28 -05:00
Tejun Heo
6b00769fe1 block: add request->raw_data_len
With padding and draining moved into it, block layer now may extend
requests as directed by queue parameters, so now a request has two
sizes - the original request size and the extended size which matches
the size of area pointed to by bios and later by sgs.  The latter size
is what lower layers are primarily interested in when allocating,
filling up DMA tables and setting up the controller.

Both padding and draining extend the data area to accomodate
controller characteristics.  As any controller which speaks SCSI can
handle underflows, feeding larger data area is safe.

So, this patch makes the primary data length field, request->data_len,
indicate the size of full data area and add a separate length field,
request->raw_data_len, for the unmodified request size.  The latter is
used to report to higher layer (userland) and where the original
request size should be fed to the controller or device.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-02-19 11:36:35 +01:00
Tony Battersby
4d2de3a50c [SCSI] fix BUG when sum(scatterlist) > bufflen
When sending a SCSI command to a tape drive via the SCSI Generic (sg)
driver, if the command has a data transfer length more than
scatter_elem_sz (32 KB default) and not a multiple of 512, then I either
hit BUG_ON(!valid_dma_direction(direction)) in dma_unmap_sg() or else
the command never completes (depending on the LLDD).

When constructing scatterlists, the sg driver rounds up the scatterlist
element sizes to be a multiple of 512.  This can result in
sum(scatterlist lengths) > bufflen.  In this case, scsi_req_map_sg()
incorrectly sets bio->bi_size to sum(scatterlist lengths) rather than to
bufflen.  When the command completes, req_bio_endio() detects that
bio->bi_size != 0, and so it doesn't call bio_endio().  This causes the
command to be resubmitted, resulting in BUG_ON or the command never
completing.

This patch makes scsi_req_map_sg() set bio->bi_size to bufflen rather
than to sum(scatterlist lengths), which fixes the problem.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-07 18:02:44 -06:00
FUJITA Tomonori
99c84dbdc7 iommu sg merging: call dma_set_seg_boundary in __scsi_alloc_queue()
This is a one-line patch to add the following to __scsi_alloc_queue():

dma_set_seg_boundary(dev, shost->dma_boundary);

This is the simplest approach but the result looks odd,
__scsi_alloc_queue() does:

blk_queue_segment_boundary(q, shost->dma_boundary);
dma_set_seg_boundary(dev, shost->dma_boundary);
blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));

I think that it would be better to set up segment boundary in the same
way as we did for the maximum segment size. That is, removing
shost->dma_boundary and LLDs call pci_set_dma_seg_boundary (or its
friends).

Then __scsi_alloc_queue() can set up both limits in the same way:

blk_queue_segment_boundary(q, dma_get_seg_boundary(dev));
blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));

killing dma_boundary in scsi_host_template needs a large patch for
libata (dma_boundary is used by only libata and sym53c8xx). I'll send
a patch to do that if it is acceptable. James and Jeff?

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:12 -08:00
FUJITA Tomonori
860ac568e8 iommu sg merging: call blk_queue_segment_boundary in __scsi_alloc_queue
request_queue and device struct must have the same value of a segment
size limit. This patch adds blk_queue_segment_boundary in
__scsi_alloc_queue so LLDs don't need to call both
blk_queue_segment_boundary and set_dma_max_seg_size. A LLD can change
the default value (64KB) can call device_dma_parameters accessors like
pci_set_dma_max_seg_size when allocating scsi_host.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:11 -08:00
FUJITA Tomonori
3d9dd6eef8 [SCSI] handle scsi_init_queue failure properly
scsi_init_queue is expected to clean up allocated things when it
fails.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:14:25 -06:00
FUJITA Tomonori
b172b6e99e [SCSI] destroy scsi_bidi_sdb_cache in scsi_exit_queue
Needs to call kmem_cache_destroy for scsi_bidi_sdb_cache in
scsi_exit_queue.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:14:25 -06:00
James Bottomley
d3f46f39b7 [SCSI] remove use_sg_chaining
With the sg table code, every SCSI driver is now either chain capable
or broken (or has sg_tablesize set so chaining is never activated), so
there's no need to have a check in the host template.

Also tidy up the code by moving the scatterlist size defines into the
SCSI includes and permit the last entry of the scatterlist pools not
to be a power of two.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:14:02 -06:00
Kiyoshi Ueda
b8de163184 [SCSI] bidirectional: fix up for the new blk_end_request code
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:03:41 -06:00
Boaz Harrosh
6f9a35e2da [SCSI] bidirectional command support
At the block level bidi request uses req->next_rq pointer for a second
bidi_read request.
At Scsi-midlayer a second scsi_data_buffer structure is used for the
bidi_read part. This bidi scsi_data_buffer is put on
request->next_rq->special. Struct scsi_cmnd is not changed.

- Define scsi_bidi_cmnd() to return true if it is a bidi request and a
  second sgtable was allocated.

- Define scsi_in()/scsi_out() to return the in or out scsi_data_buffer
  from this command This API is to isolate users from the mechanics of
  bidi.

- Define scsi_end_bidi_request() to do what scsi_end_request() does but
  for a bidi request. This is necessary because bidi commands are a bit
  tricky here. (See comments in body)

- scsi_release_buffers() will also release the bidi_read scsi_data_buffer

- scsi_io_completion() on bidi commands will now call
  scsi_end_bidi_request() and return.

- The previous work done in scsi_init_io() is now done in a new
  scsi_init_sgtable() (which is 99% identical to old scsi_init_io())
  The new scsi_init_io() will call the above twice if needed also for
  the bidi_read command. Only at this point is a command bidi.

- In scsi_error.c at scsi_eh_prep/restore_cmnd() make sure bidi-lld is not
  confused by a get-sense command that looks like bidi. This is done
  by puting NULL at request->next_rq, and restoring.

[jejb: update to sg_table and resolve conflicts
also update to blk-end-request and resolve conflicts]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:03:41 -06:00
Boaz Harrosh
30b0c37b27 [SCSI] implement scsi_data_buffer
In preparation for bidi we abstract all IO members of scsi_cmnd,
that will need to duplicate, into a substructure.

- Group all IO members of scsi_cmnd into a scsi_data_buffer
  structure.
- Adjust accessors to new members.
- scsi_{alloc,free}_sgtable receive a scsi_data_buffer instead of
  scsi_cmnd. And work on it.
- Adjust scsi_init_io() and  scsi_release_buffers() for above
  change.
- Fix other parts of scsi_lib/scsi.c to members migration. Use
  accessors where appropriate.

- fix Documentation about scsi_cmnd in scsi_host.h

- scsi_error.c
  * Changed needed members of struct scsi_eh_save.
  * Careful considerations in scsi_eh_prep/restore_cmnd.

- sd.c and sr.c
  * sd and sr would adjust IO size to align on device's block
    size so code needs to change once we move to scsi_data_buff
    implementation.
  * Convert code to use scsi_for_each_sg
  * Use data accessors where appropriate.

- tgt: convert libsrp to use scsi_data_buffer

- isd200: This driver still bangs on scsi_cmnd IO members,
  so need changing

[jejb: rebased on top of sg_table patches fixed up conflicts
and used the synergy to eliminate use_sg and sg_count]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:03:40 -06:00
Boaz Harrosh
bb52d82f45 [SCSI] tgt: use scsi_init_io instead of scsi_alloc_sgtable
If we export scsi_init_io()/scsi_release_buffers() instead of
scsi_{alloc,free}_sgtable() from scsi_lib than tgt code is much more
insulated from scsi_lib changes. As a bonus it will also gain bidi
capability when it comes.

[jejb: rebase on to sg_table and fix up rejections]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-30 13:03:40 -06:00