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path: root/drivers/scsi/scsi_lib.c
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2009-06-21sd, sr: fix Driver 'sd' needs updating messageHannes Reinecke
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>
2009-06-12[SCSI] Merge branch 'linus'James Bottomley
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>
2009-05-23[SCSI] limit state transitions in scsi_internal_device_unblockTakahiro Yasui
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>
2009-05-22Merge branch 'master' into for-2.6.31Jens Axboe
Conflicts: drivers/block/hd.c drivers/block/mg_disk.c Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19scsi_lib: remove unused variableBoaz Harrosh
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>
2009-05-12scsi: fix resid_len mis-conversion in scsi_end_request()Tejun Heo
Commit c3a4d78c580de4edc9ef0f7c59812fb02ceb037f 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>
2009-05-11scsi: simplify the bidi completionFUJITA Tomonori
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>
2009-05-11block: implement and enforce request peek/start/fetchTejun Heo
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>
2009-05-11block: blk_rq_[cur_]_{sectors|bytes}() usage cleanupTejun Heo
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>
2009-05-11block: cleanup rq->data_len usagesTejun Heo
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>
2009-05-11block: convert to pos and nr_sectors accessorsTejun Heo
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>
2009-05-11block: implement blk_rq_pos/[cur_]sectors() and convert obvious onesTejun Heo
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>
2009-05-11block: add rq->resid_lenTejun Heo
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>
2009-04-28block: kill rq->dataTejun Heo
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>
2009-04-28block: implement and use [__]blk_end_request_all()Tejun Heo
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>
2009-04-27[SCSI] fix q->lock not held warning when target is busyMike Christie
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>
2009-04-03[SCSI] fix recovered error handlingJames Bottomley
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>
2009-03-12[SCSI] remove scsi_req_map_sgFUJITA Tomonori
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>
2009-02-21[SCSI] fix ABORTED_COMMAND looping forever problemJames Bottomley
Instead of terminating after five retries, commands terminated by ABORTED_COMMAND sense are retrying forever. The problem was introduced by: commit b60af5b0adf0da24c673598c8d3fb4d4189a15ce 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>
2009-01-07[SCSI] scsi_lib: fix DID_RESET status problemsJames Bottomley
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 b60af5b0adf0da24c673598c8d3fb4d4189a15ce 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>
2009-01-05[SCSI] Fix error handling for DIF/DIXMartin K. Petersen
patch commit b60af5b0adf0da24c673598c8d3fb4d4189a15ce 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[SCSI] scsi_lib: don't decrement busy counters when inserting commandsJames Bottomley
A bug was introduced by commit b60af5b0adf0da24c673598c8d3fb4d4189a15ce 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>
2009-01-02[SCSI] Fix uninitialized variable error in scsi_io_completionAlan Stern
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>
2008-12-29[SCSI] add residual argument to scsi_execute and scsi_execute_reqFUJITA Tomonori
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[SCSI] simplify scsi_io_completion()Alan Stern
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>
2008-12-13[SCSI] scsi_lib: only call scsi_unprep_request() under queue lockJames Bottomley
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>
2008-11-16[SCSI] Fix hang in starved list processingMike Christie
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>
2008-10-23[SCSI] export busy state via q->lld_busy_fn()Kiyoshi Ueda
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[SCSI] refactor sdev/starget/shost busy checkingKiyoshi Ueda
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[SCSI] fix removable device inability to detect disk changesJames Bottomley
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>
2008-10-13[SCSI] modify scsi to handle new fail fast flags.Mike Christie
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[SCSI] Add helper code so transport classes/driver can control queueing (v3)Mike Christie
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>
2008-10-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6Linus Torvalds
* 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. ...
2008-10-09block: unify request timeout handlingJens Axboe
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>
2008-10-03[SCSI] Update the SCSI state model to allow blocking in the created stateJames Bottomley
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>
2008-09-23[SCSI] Fix hang with split requestsJames Bottomley
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>
2008-07-27[SCSI] replace __FUNCTION__ with __func__Harvey Harrison
[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>
2008-07-26[SCSI] scsi_lib: use blk_rq_tagged in scsi_request_fnMike Christie
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[SCSI] Do not retry a request whose data integrity check failedMartin K. Petersen
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[SCSI] Support devices with protection informationMartin K. Petersen
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[SCSI] fix shared tag map tag allocationMike Christie
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>
2008-07-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6Linus Torvalds
* 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 ...
2008-07-12[SCSI] fix locking in host use of blk_plug_device()James Bottomley
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[SCSI] Rename scsi_bidi_sdb_cacheMartin K. Petersen
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>
2008-07-06[SCSI] erase invalid data returned by deviceAlan Stern
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>
2008-06-05[SCSI] scsi_dh: add infrastructure for SCSI Device HandlersChandra Seetharaman
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>
2008-05-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6Linus Torvalds
* 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[SCSI] add support for variable length extended commandsBoaz Harrosh
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[SCSI] Let scsi_cmnd->cmnd use request->cmd bufferBoaz Harrosh
- 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>
2008-04-29block: make queue flags non-atomicNick Piggin
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>