Avoid taking the host-wide host_lock to check the per-host queue limit.
Instead we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
Using dev_printk variants prefixes the logging message with
the originating device, which makes debugging easier.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
scsi_put_command() is either invoked before blk_start_request() or
after block layer processing has completed. scsi_cmnd.abort_work
is scheduled from inside the SCSI timeout handler. The block layer
guarantees that either the regular completion handler
(softirq_done_fn()) or the timeout handler (rq_timed_out_fn()) is
invoked but not both. This means that scsi_put_command() is never
invoked while abort_work is scheduled. Hence remove the
cancel_delayed_work() call from scsi_put_command().
Similarly, scsi_abort_command() is only invoked from the SCSI
timeout handler. If scsi_abort_command() is invoked for a SCSI
command with the SCSI_EH_ABORT_SCHEDULED flag set this means that
scmd_eh_abort_handler() has already invoked scsi_queue_insert() and
hence that scsi_cmnd.abort_work is no longer pending. Hence also
remove the cancel_delayed_work() call from scsi_abort_command().
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Any callbacks in scsi_timeout_out() might return BLK_EH_RESET_TIMER,
in which case we should leave the result alone and not set
DID_TIME_OUT, as the command didn't actually timeout.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
After scsi_try_to_abort_cmd returns, the eh_abort_handler may have
already found that the command has completed in the device, causing
the host_byte to be nonzero (e.g. it could be DID_ABORT). When
this happens, ORing DID_TIME_OUT into the host byte will corrupt
the result field and initiate an unwanted command retry.
Fix this by using set_host_byte instead, following the model of
commit 2082ebc45a.
Cc: stable@vger.kernel.org
Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
[Fix all instances according to review comments. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Pull block layer fixes from Jens Axboe:
"Final small batch of fixes to be included before -rc1. Some general
cleanups in here as well, but some of the blk-mq fixes we need for the
NVMe conversion and/or scsi-mq. The pull request contains:
- Support for not merging across a specified "chunk size", if set by
the driver. Some NVMe devices perform poorly for IO that crosses
such a chunk, so we need to support it generically as part of
request merging avoid having to do complicated split logic. From
me.
- Bump max tag depth to 10Ki tags. Some scsi devices have a huge
shared tag space. Before we failed with EINVAL if a too large tag
depth was specified, now we truncate it and pass back the actual
value. From me.
- Various blk-mq rq init fixes from me and others.
- A fix for enter on a dying queue for blk-mq from Keith. This is
needed to prevent oopsing on hot device removal.
- Fixup for blk-mq timer addition from Ming Lei.
- Small round of performance fixes for mtip32xx from Sam Bradshaw.
- Minor stack leak fix from Rickard Strandqvist.
- Two __init annotations from Fabian Frederick"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: add __init to blkcg_policy_register
block: add __init to elv_register
block: ensure that bio_add_page() always accepts a page for an empty bio
blk-mq: add timer in blk_mq_start_request
blk-mq: always initialize request->start_time
block: blk-exec.c: Cleaning up local variable address returnd
mtip32xx: minor performance enhancements
blk-mq: ->timeout should be cleared in blk_mq_rq_ctx_init()
blk-mq: don't allow queue entering for a dying queue
blk-mq: bump max tag depth to 10K tags
block: add blk_rq_set_block_pc()
block: add notion of a chunk size for request merging
With the optimizations around not clearing the full request at alloc
time, we are leaving some of the needed init for REQ_TYPE_BLOCK_PC
up to the user allocating the request.
Add a blk_rq_set_block_pc() that sets the command type to
REQ_TYPE_BLOCK_PC, and properly initializes the members associated
with this type of request. Update callers to use this function instead
of manipulating rq->cmd_type directly.
Includes fixes from Christoph Hellwig <hch@lst.de> for my half-assed
attempt.
Signed-off-by: Jens Axboe <axboe@fb.com>
->queuecommand returns '0' for successful command submission,
so we need to set the correct SCSI midlayer return value
when calling scsi_log_completion().
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reported-by: Robert Elliott <elliott@hp.com>
Cc: Stephen Cameron <scameron@beardog.cce.hp.com>
Tested-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
This patch fixes a corner case in the previous USB Deadlock fix patch (12023e7
[SCSI] Fix USB deadlock caused by SCSI error handling).
The scenario is abort command, set flag, abort completes, send TUR, TUR
doesn't return, so we now try to abort the TUR, but scsi_abort_eh_cmnd()
will skip the abort because the flag is set and move straight to reset.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
USB requires that every command be aborted first before we escalate to reset.
In particular, USB will deadlock if we try to reset first before aborting the
command.
Unfortunately, the flag we use to tell if a command has already been aborted:
SCSI_EH_ABORT_SCHEDULED is not cleared properly leading to cases where we can
requeue a command with the flag set and proceed immediately to reset if it
fails (thus causing USB to deadlock).
Fix by clearing the SCSI_EH_ABORT_SCHEDULED flag if it has been set. Which
means this will be the second time scsi_abort_command() has been called for
the same command. IE the first abort went out, did its thing, but now the
same command has timed out again.
So this flag gets cleared, and scsi_abort_command() returns FAILED, and _no_
asynchronous abort is being scheduled. scsi_times_out() will then proceed to
call scsi_eh_scmd_add(). But as we've cleared the SCSI_EH_ABORT_SCHEDULED
flag the SCSI_EH_CANCEL_CMD flag will continue to be set, and the command will
be aborted with the main SCSI EH routine.
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Andreas Reis <andreas.reis@gmail.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
We're seeing a case where the contents of scmd->result isn't being reset after
a SCSI command encounters an error, is resubmitted, times out and then gets
handled. The error handler acts on the stale result of the previous error
instead of the timeout. Fix this by properly zeroing the scmd->status before
the command is resubmitted.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
We unconditionally execute scsi_eh_get_sense() to make sure all failed
commands that should have sense attached, do. However, the routine forgets
that some commands, because of the way they fail, will not have any sense code
... we should not bother them with a REQUEST_SENSE command. Fix this by
testing to see if we actually got a CHECK_CONDITION return and skip asking for
sense if we don't.
Tested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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>
The former minimum valid value of 'eh_deadline' is 1s, which means
the earliest occasion to shorten EH is 1 second later since a
command is failed or timed out. But if we want to skip EH steps
ASAP, we have to wait until the first EH step is finished. If the
duration of the first EH step is long, this waiting time is
excruciating. So, it is necessary to accept 0 as the minimum valid
value for 'eh_deadline'.
According to my test, with Hannes' patchset 'New EH command timeout
handler' as well, the minimum IO time is improved from 73s
(eh_deadline = 1) to 43s(eh_deadline = 0) when commands are timed
out by disabling RSCN and target port.
Signed-off-by: Ren Mingxin <renmx@cn.fujitsu.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
32bit accesses are guaranteed to be atomic, so we can remove
the spinlock when checking for eh_deadline. We only need to
make sure to catch any updates which might happened during
the call to time_before(); if so we just recheck with the
correct value.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
When a command runs into a timeout we need to send an 'ABORT TASK'
TMF. This is typically done by the 'eh_abort_handler' LLDD callback.
Conceptually, however, this function is a normal SCSI command, so
there is no need to enter the error handler.
This patch implements a new scsi_abort_command() function which
invokes an asynchronous function scsi_eh_abort_handler() to
abort the commands via the usual 'eh_abort_handler'.
If abort succeeds the command is either retried or terminated,
depending on the number of allowed retries. However, 'eh_eflags'
records the abort, so if the retry would fail again the
command is pushed onto the error handler without trying to
abort it (again); it'll be cleared up from SCSI EH.
[hare: smatch detected stray switch fixed]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Commit 18a4d0a22e
(Handle disk devices which can not process medium access commands)
was introduced to offline any device which cannot process medium
access commands.
However, commit 3eef6257de
(Reduce error recovery time by reducing use of TURs) reduced
the number of TURs by sending it only on the first failing
command, which might or might not be a medium access command.
So in combination this results in an erratic device offlining
during EH; if the command where the TUR was sent upon happens
to be a medium access command the device will be set offline,
if not everything proceeds as normal.
This patch moves the check to the final test, eliminating
this problem.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
If a command abort fails there is a fair chance that all other
aborts will be failing, too.
So we should be calling LUN reset directly after the first failed
abort and skip aborting the remaining commands.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patchs adds an 'eh_deadline' sysfs attribute to the scsi
host which limits the overall runtime of the SCSI EH.
The 'eh_deadline' value is stored in the now obsolete field
'resetting'.
When a command is failed the start time of the EH is stored
in 'last_reset'. If the overall runtime of the SCSI EH is longer
than last_reset + eh_deadline, the EH is short-circuited and
falls through to issue a host reset only.
[jejb: add comments in Scsi_Host about new fields]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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>
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>
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>
We should be modifying the host_byte status in scsi_check_sense()
directly; this saves us to introduce a special return code for
each and every condition.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
The patch set is mostly driver updates (usf, zfcp, lpfc, mpt2sas,
megaraid_sas, bfa, ipr) and a few bug fixes. Also of note is that the
Buslogic driver has been rewritten to a better coding style and 64 bit support
added. We also removed the libsas limitation on 16 bytes for the command size
(currently no drivers make use of this).
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull first round of SCSI updates from James Bottomley:
"The patch set is mostly driver updates (usf, zfcp, lpfc, mpt2sas,
megaraid_sas, bfa, ipr) and a few bug fixes. Also of note is that the
Buslogic driver has been rewritten to a better coding style and 64 bit
support added. We also removed the libsas limitation on 16 bytes for
the command size (currently no drivers make use of this)"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (101 commits)
[SCSI] megaraid: minor cut and paste error fixed.
[SCSI] ufshcd-pltfrm: remove unnecessary dma_set_coherent_mask() call
[SCSI] ufs: fix register address in UIC error interrupt handling
[SCSI] ufshcd-pltfrm: add missing empty slot in ufs_of_match[]
[SCSI] ufs: use devres functions for ufshcd
[SCSI] ufs: Fix the response UPIU length setting
[SCSI] ufs: rework link start-up process
[SCSI] ufs: remove version check before IS reg clear
[SCSI] ufs: amend interrupt configuration
[SCSI] ufs: wrap the i/o access operations
[SCSI] storvsc: Update the storage protocol to win8 level
[SCSI] storvsc: Increase the value of scsi timeout for storvsc devices
[SCSI] MAINTAINERS: Add myself as the maintainer for BusLogic SCSI driver
[SCSI] BusLogic: Port driver to 64-bit.
[SCSI] BusLogic: Fix style issues
[SCSI] libiscsi: Added new boot entries in the session sysfs
[SCSI] aacraid: Fix for arrays are going offline in the system. System hangs
[SCSI] ipr: IOA Status Code(IOASC) update
[SCSI] sd: Update WRITE SAME heuristics
[SCSI] fnic: potential dead lock in fnic_is_abts_pending()
...
Introduce eh_timeout which can be used for error handling purposes. This
was previously hardcoded to 10 seconds in the SCSI error handling
code. However, for some fast-fail scenarios it is necessary to be able
to tune this as it can take several iterations (bus device, target, bus,
controller) before we give up.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
scsi_send_eh_cmnd() is calling queuecommand() directly, so
it needs to check the return value here.
The only valid return codes for queuecommand() are 'busy'
states, so we need to wait for a bit to allow the LLDD
to recover.
Based on an earlier patch from Wen Xiong.
[jejb: fix confusion between msec and jiffies values and other issues]
[bvanassche: correct stall_for interval]
Cc: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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>
