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path: root/drivers/scsi/scsi_lib.c
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2014-07-25scsi: unwind blk_end_request_all and blk_end_request_err callsChristoph Hellwig
Replace the calls to the various blk_end_request variants with opencode equivalents. Blk-mq is using a model that gives the driver control between the bio updates and the actual completion, and making the old code follow that same model allows us to keep the code more similar for both paths. 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>
2014-07-25scsi: only maintain target_blocked if the driver has a target queue limitChristoph Hellwig
This saves us an atomic operation for each I/O submission and completion for the usual case where the driver doesn't set a per-target can_queue value. Only a few iscsi hardware offload drivers set the per-target can_queue value at the moment. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> 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>
2014-07-25scsi: fix the {host,target,device}_blocked counter messChristoph Hellwig
Seems like these counters are missing any sort of synchronization for updates, as a over 10 year old comment from me noted. Fix this by using atomic counters, and while we're at it also make sure they are in the same cacheline as the _busy counters and not needlessly stored to in every I/O completion. With the new model the _busy counters can temporarily go negative, so all the readers are updated to check for > 0 values. Longer term every successful I/O completion will reset the counters to zero, so the temporarily negative values will not cause any harm. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> 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>
2014-07-25scsi: convert device_busy to atomic_tChristoph Hellwig
Avoid taking the queue_lock to check the per-device 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. Unlike the host and target busy counters this doesn't allow us to avoid the queue_lock in the request_fn due to the way the interface works, but it'll allow us to prepare for using the blk-mq code, which doesn't use the queue_lock at all, and it at least avoids a queue_lock round trip in scsi_device_unbusy, which is still important given how busy the queue_lock is. Signed-off-by: Christoph Hellwig <hch@lst.de> 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>
2014-07-25scsi: convert host_busy to atomic_tChristoph Hellwig
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>
2014-07-25scsi: convert target_busy to an atomic_tChristoph Hellwig
Avoid taking the host-wide host_lock to check the per-target 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>
2014-07-25scsi: push host_lock down into scsi_{host,target}_queue_readyChristoph Hellwig
Prepare for not taking a host-wide lock in the dispatch path by pushing the lock down into the places that actually need it. Note that this patch is just a preparation step, as it will actually increase lock roundtrips and thus decrease performance on its own. 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>
2014-07-25scsi: set ->scsi_done before calling scsi_dispatch_cmdChristoph Hellwig
The blk-mq code path will set this to a different function, so make the code simpler by setting it up in a legacy-request specific place. 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>
2014-07-25scsi: centralize command re-queueing in scsi_dispatch_fnChristoph Hellwig
Make sure we only have the logic for requeing commands in one place. 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>
2014-07-25scsi: split __scsi_queue_insertChristoph Hellwig
Factor out a helper to set the _blocked values, which we'll reuse for the blk-mq code path. 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>
2014-07-25scsi: add scsi_setup_cmnd helperChristoph Hellwig
Factor out command setup code that will be shared with the blk-mq code path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Webb Scales <webbnh@hp.com>
2014-07-17scsi: mark scsi_setup_blk_pc_cmnd staticChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17scsi: set sc_data_direction in common codeChristoph Hellwig
The data direction fiel in the SCSI command is derived only from the block request structure. Move setting it up into common code instead of duplicating it in the ULDs. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17scsi: restructure command initialization for TYPE_FS requestsChristoph Hellwig
We should call the device handler prep_fn for all TYPE_FS requests, not just simple read/write calls that are handled by the disk driver. Restructure the common I/O code to call the prep_fn handler and zero out the CDB, and just leave the call to scsi_init_io to the ULDs. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17scsi: move the nr_phys_segments assert into scsi_init_ioChristoph Hellwig
scsi_init_io should only be called for requests that transfer data, so move the assert that a request has segments from the callers into scsi_init_io. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17scsi_lib: remove the description string in scsi_io_completion()Maurizio Lombardi
During IO with fabric faults, one generally sees several "Unhandled error code" messages in the syslog as shown below: sd 4:0:6:2: [sdbw] Unhandled error code sd 4:0:6:2: [sdbw] Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK sd 4:0:6:2: [sdbw] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 end_request: I/O error, dev sdbw, sector 0 This comes from scsi_io_completion (in scsi_lib.c) while handling error codes other than DID_RESET or not deferred sense keys i.e. this is actually handled by the SCSI mid layer. But what gets displayed here is "Unhandled error code" which is quite misleading as it indicates something that is not addressed by the mid layer. The description string is based on the sense key and sometimes on the additional sense code; since the ACTION_FAIL case always prints the sense key and the additional sense code, this patch removes the description string completely because it does not add useful information. Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17scsi: remove various exports that were only used by scsi_tgtChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17scsi: use dev_printk variants where possibleHannes Reinecke
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>
2014-07-17scsi: handle flush errors properlyJames Bottomley
Flush commands don't transfer data and thus need to be special cased in the I/O completion handler so that we can propagate errors to the block layer and filesystem. Signed-off-by: James Bottomley <JBottomley@Parallels.com> Reported-by: Steven Haber <steven@qumulo.com> Tested-by: Steven Haber <steven@qumulo.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-11Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
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
2014-06-09Merge tag 'scsi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI updates from James Bottomley: "This patch consists of the usual driver updates (qla2xxx, qla4xxx, lpfc, be2iscsi, fnic, ufs, NCR5380) The NCR5380 is the addition to maintained status of a long neglected driver for older hardware. In addition there are a lot of minor fixes and cleanups and some more updates to make scsi mq ready" * tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (130 commits) include/scsi/osd_protocol.h: remove unnecessary __constant mvsas: Recognise device/subsystem 9485/9485 as 88SE9485 Revert "be2iscsi: Fix processing cqe for cxn whose endpoint is freed" mptfusion: fix msgContext in mptctl_hp_hostinfo acornscsi: remove linked command support scsi/NCR5380: dprintk macro fusion: Remove use of DEF_SCSI_QCMD fusion: Add free msg frames to the head, not tail of list mpt2sas: Add free smids to the head, not tail of list mpt2sas: Remove use of DEF_SCSI_QCMD mpt2sas: Remove uses of serial_number mpt3sas: Remove use of DEF_SCSI_QCMD mpt3sas: Remove uses of serial_number qla2xxx: Use kmemdup instead of kmalloc + memcpy qla4xxx: Use kmemdup instead of kmalloc + memcpy qla2xxx: fix incorrect debug printk be2iscsi: Bump the driver version be2iscsi: Fix processing cqe for cxn whose endpoint is freed be2iscsi: Fix destroy MCC-CQ before MCC-EQ is destroyed be2iscsi: Fix memory corruption in MBX path ...
2014-06-06block: add blk_rq_set_block_pc()Jens Axboe
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>
2014-06-02Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into nextLinus Torvalds
Pull block core updates from Jens Axboe: "It's a big(ish) round this time, lots of development effort has gone into blk-mq in the last 3 months. Generally we're heading to where 3.16 will be a feature complete and performant blk-mq. scsi-mq is progressing nicely and will hopefully be in 3.17. A nvme port is in progress, and the Micron pci-e flash driver, mtip32xx, is converted and will be sent in with the driver pull request for 3.16. This pull request contains: - Lots of prep and support patches for scsi-mq have been integrated. All from Christoph. - API and code cleanups for blk-mq from Christoph. - Lots of good corner case and error handling cleanup fixes for blk-mq from Ming Lei. - A flew of blk-mq updates from me: * Provide strict mappings so that the driver can rely on the CPU to queue mapping. This enables optimizations in the driver. * Provided a bitmap tagging instead of percpu_ida, which never really worked well for blk-mq. percpu_ida relies on the fact that we have a lot more tags available than we really need, it fails miserably for cases where we exhaust (or are close to exhausting) the tag space. * Provide sane support for shared tag maps, as utilized by scsi-mq * Various fixes for IO timeouts. * API cleanups, and lots of perf tweaks and optimizations. - Remove 'buffer' from struct request. This is ancient code, from when requests were always virtually mapped. Kill it, to reclaim some space in struct request. From me. - Remove 'magic' from blk_plug. Since we store these on the stack and since we've never caught any actual bugs with this, lets just get rid of it. From me. - Only call part_in_flight() once for IO completion, as includes two atomic reads. Hopefully we'll get a better implementation soon, as the part IO stats are now one of the more expensive parts of doing IO on blk-mq. From me. - File migration of block code from {mm,fs}/ to block/. This includes bio.c, bio-integrity.c, bounce.c, and ioprio.c. From me, from a discussion on lkml. That should describe the meat of the pull request. Also has various little fixes and cleanups from Dave Jones, Shaohua Li, Duan Jiong, Fengguang Wu, Fabian Frederick, Randy Dunlap, Robert Elliott, and Sam Bradshaw" * 'for-3.16/core' of git://git.kernel.dk/linux-block: (100 commits) blk-mq: push IPI or local end_io decision to __blk_mq_complete_request() blk-mq: remember to start timeout handler for direct queue block: ensure that the timer is always added blk-mq: blk_mq_unregister_hctx() can be static blk-mq: make the sysfs mq/ layout reflect current mappings blk-mq: blk_mq_tag_to_rq should handle flush request block: remove dead code in scsi_ioctl:blk_verify_command blk-mq: request initialization optimizations block: add queue flag for disabling SG merging block: remove 'magic' from struct blk_plug blk-mq: remove alloc_hctx and free_hctx methods blk-mq: add file comments and update copyright notices blk-mq: remove blk_mq_alloc_request_pinned blk-mq: do not use blk_mq_alloc_request_pinned in blk_mq_map_request blk-mq: remove blk_mq_wait_for_tags blk-mq: initialize request in __blk_mq_alloc_request blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request blk-mq: add helper to insert requests from irq context blk-mq: remove stale comment for blk_mq_complete_request() blk-mq: allow non-softirq completions ...
2014-05-19scsi: reintroduce scsi_driver.init_commandChristoph Hellwig
Instead of letting the ULD play games with the prep_fn move back to the model of a central prep_fn with a callback to the ULD. This already cleans up and shortens the code by itself, and will be required to properly support blk-mq in the SCSI midlayer. 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>
2014-05-19scsi: remove scsi_end_requestChristoph Hellwig
By folding scsi_end_request into its only caller we can significantly clean up the completion logic. We can use simple goto labels now to only have a single place to finish or requeue command there instead of the previous convoluted logic. 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>
2014-05-19scsi: explicitly release bidi buffersChristoph Hellwig
Instead of trying to guess when we have a BIDI buffer in scsi_release_buffers add a function to explicitly free the BIDI ressoures in the one place that handles them. This avoids needing a special __scsi_release_buffers for the case where we already have freed the request as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
2014-04-21[SCSI] Fix command result state propagationAlan Stern
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>
2014-04-21[SCSI] don't reference freed command in scsi_prep_returnChristoph Hellwig
Patch commit 0479633686d370303e3430256ace4bd5f7f138dc Author: Christoph Hellwig <hch@infradead.org> Date: Thu Feb 20 14:20:55 2014 -0800 [SCSI] do not manipulate device reference counts in scsi_get/put_command Introduced a use after free:I in the kill case of scsi_prep_return we have to release our device reference, but we do this trying to reference the just freed command. Use the local sdev pointer instead. Fixes: 0479633686d370303e3430256ace4bd5f7f138dc Reported-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-04-21[SCSI] don't reference freed command in scsi_init_sgtableChristoph Hellwig
Patch commit 0479633686d370303e3430256ace4bd5f7f138dc Author: Christoph Hellwig <hch@infradead.org> Date: Thu Feb 20 14:20:55 2014 -0800 [SCSI] do not manipulate device reference counts in scsi_get/put_command Introduced a use after free: when scsi_init_io fails we have to release our device reference, but we do this trying to reference the just freed command. Add a local scsi_device pointer to fix this. Fixes: 0479633686d370303e3430256ace4bd5f7f138dc Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-04-15block: remove struct request buffer memberJens Axboe
This was used in the olden days, back when onions were proper yellow. Basically it mapped to the current buffer to be transferred. With highmem being added more than a decade ago, most drivers map pages out of a bio, and rq->buffer isn't pointing at anything valid. Convert old style drivers to just use bio_data(). For the discard payload use case, just reference the page in the bio. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-15Merge tag 'v3.15-rc1' into for-3.16/coreJens Axboe
We don't like this, but things have diverged with the blk-mq fixes in 3.15-rc1. So merge it in.
2014-04-09scsi: Make sure cmd_flags are 64-bitMartin K. Petersen
cmd_flags in struct request is now 64 bits wide but the scsi_execute functions truncated arguments passed to int leading to errors. Make sure the flags parameters are u64. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Jens Axboe <axboe@fb.com> CC: Jan Kara <jack@suse.cz> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09block: remove 'q' parameter from kblockd_schedule_*_work()Jens Axboe
The queue parameter is never used, just get rid of it. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-03-15[SCSI] remove a useless get/put_device pair in scsi_requeue_commandChristoph Hellwig
Avoid a spurious device get/put pair by cleaning up scsi_requeue_command and folding scsi_unprep_request into it. 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[SCSI] remove a useless get/put_device pair in scsi_next_commandBart Van Assche
Eliminate a get_device() / put_device() pair from scsi_next_command(). Both are atomic operations hence removing these slightly improves performance. [hch: slight changes due to different context] Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] remove a useless get/put_device pair in scsi_request_fnBart Van Assche
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[SCSI] do not manipulate device reference counts in scsi_get/put_commandChristoph Hellwig
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[SCSI] avoid taking host_lock in scsi_run_queue unless nessecaryChristoph Hellwig
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[SCSI] Add timeout to avoid infinite command retryEiichi Tsukata
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>
2014-02-17Fix uses of dma_max_pfn() when converting to a limiting addressRussell King
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: 8e0cb8a1f6ac ("ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations") Fixes: 7d35496dd982 ("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>
2013-10-31ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculationsSantosh Shilimkar
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>
2013-09-03Merge branch 'for-3.12' of ↵Linus Torvalds
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
2013-08-26[SCSI] Generate uevents on certain unit attention codesEwan D. Milne
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>
2013-08-23[SCSI] Return ENODATA on medium errorHannes Reinecke
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[SCSI] return ENOSPC on thin provisioning failureHannes Reinecke
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[SCSI] Document enhanced error codesHannes Reinecke
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>
2013-08-23ata: acpi: rework the ata acpi bind supportAaron Lu
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>
2013-07-09[SCSI] enable destruction of blocked devices which fail LUN scanningBart Van Assche
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[SCSI] Fix race between starved list and device removalJames Bottomley
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>
2013-05-06[SCSI] sd: use REQ_PM in sd's runtime suspend operationLin Ming
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>