This patch tries to shorten the path length of scsi_cmd_to_driver(). As only
REQ_TYPE_BLOCK_PC commands can be submitted without a driver, so we could
avoid the related NULL checking, as long as we make sure we don't use it for
REQ_TYPE_BLOCK_PC type commands. Plus, this fixes a bug where you get
different behaviors from REQ_TYPE_BLOCK_PC commands when a driver is and isn't
attached.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This is a particularly nasty SCSI ATA Translation Layer (SATL) problem.
SAT-2 says (section 8.12.2)
if the device is in the stopped state as the result of
processing a START STOP UNIT command (see 9.11), then the SATL
shall terminate the TEST UNIT READY command with CHECK CONDITION
status with the sense key set to NOT READY and the additional
sense code of LOGICAL UNIT NOT READY, INITIALIZING COMMAND
REQUIRED;
mpt2sas internal SATL seems to implement this. The result is very confusing
standby behaviour (using hdparm -y). If you suspend a drive and then send
another command, usually it wakes up. However, if the next command is a TEST
UNIT READY, the SATL sees that the drive is suspended and proceeds to follow
the SATL rules for this, returning NOT READY to all subsequent commands. This
means that the ordering of TEST UNIT READY is crucial: if you send TUR and
then a command, you get a NOT READY to both back. If you send a command and
then a TUR, you get GOOD status because the preceeding command woke the drive.
This bit us badly because
commit 85ef06d1d2
Author: Tejun Heo <tj@kernel.org>
Date: Fri Jul 1 16:17:47 2011 +0200
block: flush MEDIA_CHANGE from drivers on close(2)
Changed our ordering on TEST UNIT READY commands meaning that SATA drives
connected to an mpt2sas now suspend and refuse to wake (because the mpt2sas
SATL sees the suspend *before* the drives get awoken by the next ATA command)
resulting in lots of failed commands.
The standard is completely nuts forcing this inconsistent behaviour, but we
have to work around it.
The fix for this is twofold:
1. Set the allow_restart flag so we wake the drive when we see it has been
suspended
2. Return all TEST UNIT READY status directly to the mid layer without any
further error handling which prevents us causing error handling which
may offline the device just because of a media check TUR.
Reported-by: Matthias Prager <linux@matthiasprager.de>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
A quick reading of scsi_error_handler() one could come away with the
impression that it does its wakeup event check while the task state is
TASK_RUNNING. In fact it sets TASK_INTERRUPTIBLE at the bottom of the
loop, but that is ~50 lines down.
Just set TASK_INTERRUPTIBLE at the top of loop and be done.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Rapid ata hotplug on a libsas controller results in cases where libsas
is waiting indefinitely on eh to perform an ata probe.
A race exists between scsi_schedule_eh() and scsi_restart_operations()
in the case when scsi_restart_operations() issues i/o to other devices
in the sas domain. When this happens the host state transitions from
SHOST_RECOVERY (set by scsi_schedule_eh) back to SHOST_RUNNING and
->host_busy is non-zero so we put the eh thread to sleep even though
->host_eh_scheduled is active.
Before putting the error handler to sleep we need to check if the
host_state needs to return to SHOST_RECOVERY for another trip through
eh. Since i/o that is released by scsi_restart_operations has been
blocked for at least one eh cycle, this implementation allows those
i/o's to run before another eh cycle starts to discourage hung task
timeouts.
Cc: <stable@vger.kernel.org>
Reported-by: Tom Jackson <thomas.p.jackson@intel.com>
Tested-by: Tom Jackson <thomas.p.jackson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Pull trivial updates from Jiri Kosina:
"As usual, it's mostly typo fixes, redundant code elimination and some
documentation updates."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (57 commits)
edac, mips: don't change code that has been removed in edac/mips tree
xtensa: Change mail addresses of Hannes Weiner and Oskar Schirmer
lib: Change mail address of Oskar Schirmer
net: Change mail address of Oskar Schirmer
arm/m68k: Change mail address of Sebastian Hess
i2c: Change mail address of Oskar Schirmer
net: Fix tcp_build_and_update_options comment in struct tcp_sock
atomic64_32.h: fix parameter naming mismatch
Kconfig: replace "--- help ---" with "---help---"
c2port: fix bogus Kconfig "default no"
edac: Fix spelling errors.
qla1280: Remove redundant NULL check before release_firmware() call
remoteproc: remove redundant NULL check before release_firmware()
qla2xxx: Remove redundant NULL check before release_firmware() call.
aic94xx: Get rid of redundant NULL check before release_firmware() call
tehuti: delete redundant NULL check before release_firmware()
qlogic: get rid of a redundant test for NULL before call to release_firmware()
bna: remove redundant NULL test before release_firmware()
tg3: remove redundant NULL test before release_firmware() call
typhoon: get rid of redundant conditional before all to release_firmware()
...
Commit 18a4d0a22e ("[SCSI] Handle disk devices which can not process
medium access commands") introduced a bug in which we would attempt to
dereference the scsi driver even when the device had no ULD attached.
Ensure that a driver is registered and make the driver accessor function
more resilient to errors during device discovery.
Reported-by: Elric Fu <elricfu1@gmail.com>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have experienced several devices which fail in a fashion we do not
currently handle gracefully in SCSI. After a failure these devices will
respond to the SCSI primary command set (INQUIRY, TEST UNIT READY, etc.)
but any command accessing the storage medium will time out.
The following patch adds an callback that can be used by upper level
drivers to inspect the results of an error handling command. This in
turn has been used to implement additional checking in the SCSI disk
driver.
If a medium access command fails twice but TEST UNIT READY succeeds both
times in the subsequent error handling we will offline the device. The
maximum number of failed commands required to take a device offline can
be tweaked in sysfs.
Also add a new error flag to scsi_debug which allows this scenario to be
easily reproduced.
[jejb: fix up integer parsing to use kstrtouint]
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Permanent target failures are non-retryable and should be classified as
TARGET_ERROR; otherwise dm-multipath will retry an IO request that will
always fail at the target.
A SCSI command that fails with ILLEGAL_REQUEST sense and Additional
sense 0x20, 0x21, 0x24 or 0x26 represents a permanent TARGET_ERROR.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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>
With previous change, now the ata port runtime suspend will happen as:
disk suspend --> scsi target suspend --> scsi host suspend --> ata port
suspend
ata port(parent device) suspend need to schedule scsi EH which will resume
scsi host(child device). Then the child device resume will in turn make
parent device resume first. This is kind of recursive.
This patch adds a new flag Scsi_Host::eh_noresume.
ata port will set this flag to skip the runtime PM calls on scsi host.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some CD-ROMs fail to report a media change correctly. The specific
one for this patch simply fails to respond to commands, then gives a
UNIT ATTENTION after being reset which returns ASC/ASCQ 28/00. This
is out of spec behaviour, but add a check in the eat CC/UA on reset
path to catch this case so the CD-ROM will function somewhat properly.
[jejb: fixed up white space and accepted without signoff]
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
In error recovery, most scsi error recovery stages will send a TUR command
for every bad command when a driver's error handler reports success. When
several bad commands to the same device, this results in a device
being probed multiple times.
This becomes very problematic if the device or connection is in a state
where the device still doesn't respond to commands even after a recovery
function returns success. The error handler must wait for the test
commands to time out. The time waiting for the redundant commands can
drastically lengthen error recovery.
This patch alters the scsi mid-layer's error routines to send test commands
once per device instead of once per bad command. This can drastically
lower error recovery time.
[jejb: fixed up whitespace and formatting]
Signed-of-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
At least log the message that we received a THIN PROVISIONING SOFT
THRESHOLD REACHED Unit Attention. Also added it to unit attention
decodes.
Signed-off-by: Shyam Iyer <shyam_iyer@dell.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch reduces the number of sequential pointer derefs in
drivers/scsi/scsi_error.c
This has been submitted a number of times over a couple of years. I
believe this version adresses all comments it has gathered over time.
Please apply or reject with a reason.
The benefits are:
- makes the code easier to read. Lots of sequential derefs of the same
pointers is not easy on the eye.
- theoretically at least, just dereferencing the pointers once can
allow the compiler to generally slightly faster code, so in theory
this could also be a micro speed optimization.
- reduces size of object file (tiny effect: on x86-64, in at least one
configuration, the text size decreased from 9439 bytes to 9400)
- removes some pointless (mostly trailing) whitespace.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
The current code in scsi_eh_target_reset() has an off by one error
that actually sends spurious extra resets. Since there's no real need
to reset the targets in numerical order, simply chunk up the command
recovery list doing target resets and pulling matching targets out of
the list (that also makes the loop O(N) instead of O(N^2).
[mike christie found and fixed a list_splice -> list_splice_init problem]
Reported-by: Hillf Danton<dhillf@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
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>
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.
The patch below presents a simple SCSI host lock push-down as an
equivalent transformation. No locking or other behavior should change
with this patch. All existing bugs and locking orders are preserved.
Additionally, add one parameter to queuecommand,
struct Scsi_Host *
and remove one parameter from queuecommand,
void (*done)(struct scsi_cmnd *)
Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.
Minimal code disturbance was attempted with this change. Most drivers
needed only two one-line modifications for their host lock push-down.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
REQ_HARDBARRIER is dead now, so remove the leftovers. What's left
at this point is:
- various checks inside the block layer.
- sanity checks in bio based drivers.
- now unused bio_empty_barrier helper.
- Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while,
but Xen really needs to sort out it's barrier situaton.
- setting of ordered tags in uas - dead code copied from old scsi
drivers.
- scsi different retry for barriers - it's dead and should have been
removed when flushes were converted to FS requests.
- blktrace handling of barriers - removed. Someone who knows blktrace
better should add support for REQ_FLUSH and REQ_FUA, though.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (28 commits)
[SCSI] qla4xxx: fix compilation warning
[SCSI] make error handling more robust in the face of reservations
[SCSI] tgt: fix warning
[SCSI] drivers/message/fusion: Adjust confusing if indentation
[SCSI] Return NEEDS_RETRY for eh commands with status BUSY
[SCSI] ibmvfc: Driver version 1.0.9
[SCSI] ibmvfc: Fix terminate_rport_io
[SCSI] ibmvfc: Fix rport add/delete race resulting in oops
[SCSI] lpfc 8.3.16: Change LPFC driver version to 8.3.16
[SCSI] lpfc 8.3.16: FCoE Discovery and Failover Fixes
[SCSI] lpfc 8.3.16: SLI Additions, updates, and code cleanup
[SCSI] pm8001: introduce missing kfree
[SCSI] qla4xxx: Update driver version to 5.02.00-k3
[SCSI] qla4xxx: Added AER support for ISP82xx
[SCSI] qla4xxx: Handle outstanding mbx cmds on hung f/w scenarios
[SCSI] qla4xxx: updated mbx_sys_info struct to sync with FW 4.6.x
[SCSI] qla4xxx: clear AF_DPC_SCHEDULED flage when exit from do_dpc
[SCSI] qla4xxx: Stop firmware before doing init firmware.
[SCSI] qla4xxx: Use the correct request queue.
[SCSI] qla4xxx: set correct value in sess->recovery_tmo
...
commit 5f91bb050e
Author: Michael Reed <mdr@sgi.com>
Date: Mon Aug 10 11:59:28 2009 -0500
[SCSI] reservation conflict after timeout causes device to be taken offline
Flipped us from always returning failed to always returning success in
the name of fixing the problem where reservation conflict returns from
test unit ready cause the device always to be taken offline.
Unfortuantely, it also introduced a problem whereby for commands other
than test unit ready, the eh dispatcher thinks they succeeded when
reservation conflict is returned, whereas in reality they failed. Fix
this by only returning success for the test unit ready case.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
When the transport is busy and we're sending an EH command drivers
occasionally return 'BUSY'. As this in most cases is the TUR
command sent as part of the error recovery this is a sure way
to make the error recovery escalate. Returning 'NEEDS_RETRY'
here will just retry the TUR command and eventually abort the
original command, thus making error handling far smoother.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
xen-blkfront: fix missing out label
blkdev: fix blkdev_issue_zeroout return value
block: update request stacking methods to support discards
block: fix missing export of blk_types.h
writeback: fix bad _bh spinlock nesting
drbd: revert "delay probes", feature is being re-implemented differently
drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
drbd: Disable delay probes for the upcomming release
writeback: cleanup bdi_register
writeback: add new tracepoints
writeback: remove unnecessary init_timer call
writeback: optimize periodic bdi thread wakeups
writeback: prevent unnecessary bdi threads wakeups
writeback: move bdi threads exiting logic to the forker thread
writeback: restructure bdi forker loop a little
writeback: move last_active to bdi
writeback: do not remove bdi from bdi_list
writeback: simplify bdi code a little
writeback: do not lose wake-ups in bdi threads
...
Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
scsi-ml uses REQ_TYPE_BLOCK_PC for flush requests from file
systems. The definition of REQ_TYPE_BLOCK_PC is that we don't retry
requests even when we can (e.g. UNIT ATTENTION) and we send the
response to the callers (then the callers can decide what they want).
We need a workaround such as the commit
77a4229719 to retry BLOCK_PC flush
requests. We will need the similar workaround for discard requests too
since SCSI-ml handle them as BLOCK_PC internally.
This uses REQ_TYPE_FS for flush requests from file systems instead of
REQ_TYPE_BLOCK_PC.
scsi-ml retries only REQ_TYPE_FS requests that have data to
transfer when we can retry them (e.g. UNIT_ATTENTION). However, we
also need to retry REQ_TYPE_FS requests without data because the
callers don't.
This also changes scsi_check_sense() to retry all the REQ_TYPE_FS
requests when appropriate. Thanks to scsi_noretry_cmd(),
REQ_TYPE_BLOCK_PC requests don't be retried as before.
Note that basically, this reverts the commit
77a4229719 since now we use REQ_TYPE_FS
for flush requests.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Li Zhong
James Bottomley
Dan Williams
Linus Torvalds
Santosh Y
Martin K. Petersen
Mike Snitzer
Moger, Babu
Lin Ming
TARUISI Hiroaki
David Jeffery
Shyam Iyer
Jesper Juhl
Hannes Reinecke
James Bottomley
Jeff Garzik
Christoph Hellwig
FUJITA Tomonori