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2017-12-07scsi: core: Ensure that the SCSI error handler gets woken upBart Van Assche1-0/+2
If scsi_eh_scmd_add() is called concurrently with scsi_host_queue_ready() while shost->host_blocked > 0 then it can happen that neither function wakes up the SCSI error handler. Fix this by making every function that decreases the host_busy counter wake up the error handler if necessary and by protecting the host_failed checks with the SCSI host lock. Reported-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> References: https://marc.info/?l=linux-kernel&m=150461610630736 Fixes: commit 746650160866 ("scsi: convert host_busy to atomic_t") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Tested-by: Stuart Hayes <stuart.w.hayes@gmail.com> Cc: Konstantin Khorenko <khorenko@virtuozzo.com> Cc: Stuart Hayes <stuart.w.hayes@gmail.com> Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-05scsi: Remove Scsi_Host.uspace_req_qBart Van Assche1-6/+0
A patch I wrote myself several years ago removed SCSI target support from the code under drivers/scsi. That patch removed the code that sets uspace_req_q to a non-NULL value. Hence also remove the code that depends on uspace_req_q != NULL. References: commit 066465251303 ("tgt: removal") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-06scsi: make asynchronous aborts mandatoryHannes Reinecke1-5/+0
There hasn't been any reports for HBAs where asynchronous abort would not work, so we should make it mandatory and remove the fallback. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-27scsi: allocate scsi_cmnd structures as part of struct requestChristoph Hellwig1-3/+0
Rely on the new block layer functionality to allocate additional driver specific data behind struct request instead of implementing it in SCSI itѕelf. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27scsi: remove __scsi_alloc_queueChristoph Hellwig1-2/+0
Instead do an internal export of __scsi_init_queue for the transport classes that export BSG nodes. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-08scsi: allow LLDDs to expose the queue mapping to blk-mqChristoph Hellwig1-0/+8
Just hand through the blk-mq map_queues method in the host template. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-26scsi: Avoid that toggling use_blk_mq triggers a memory leakBart Van Assche1-4/+1
This patch avoids that the following memory leak is triggered if use_blk_mq is disabled after a SCSI host has been allocated by the ib_srp driver and before the same SCSI host is freed: unreferenced object 0xffff8803a168c568 (size 256): backtrace: [<ffffffff81620c95>] kmemleak_alloc+0x45/0xa0 [<ffffffff811bb104>] __kmalloc_node+0x1e4/0x400 [<ffffffff81309fe4>] blk_mq_alloc_tag_set+0xb4/0x230 [<ffffffff814731b7>] scsi_mq_setup_tags+0xc7/0xd0 [<ffffffff81469c26>] scsi_add_host_with_dma+0x216/0x2d0 [<ffffffffa064bef5>] srp_create_target+0xe55/0x13d0 [ib_srp] [<ffffffff8143ce23>] dev_attr_store+0x13/0x20 [<ffffffff8125f030>] sysfs_kf_write+0x40/0x50 [<ffffffff8125e397>] kernfs_fop_write+0x137/0x1c0 [<ffffffff811d8c13>] __vfs_write+0x23/0x140 [<ffffffff811d92e0>] vfs_write+0xb0/0x190 [<ffffffff811da5b4>] SyS_write+0x44/0xa0 [<ffffffff8162c8a5>] entry_SYSCALL_64_fastpath+0x18/0xa8 Fixes: 9aa9cc4221f5 ("scsi: remove the disable_blk_mq host flag") Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: <stable@vger.kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-15scsi: remove the disable_blk_mq host flagChristoph Hellwig1-4/+2
We've had scsi-mq for 2.5 years now, so we can remove the unused flag to disable the code on a per-host basis that was put in for unexpected emergencies during bringup. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-15scsi: rename SCSI_MAX_{SG, SG_CHAIN}_SEGMENTSMing Lin1-1/+1
Rename SCSI_MAX_SG_SEGMENTS to SG_CHUNK_SIZE, which means the amount we fit into a single scatterlist chunk. Rename SCSI_MAX_SG_CHAIN_SEGMENTS to SG_MAX_SEGMENTS. Will move these 2 generic definitions to scatterlist.h later. Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Bart Van Assche <bart.vanassche@sandisk.com> (for ib_srp changes) Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03Merge branch 'mkp-fixes' into fixesJames Bottomley1-0/+3
2015-11-19scsi: report 'INQUIRY result too short' once per hostVitaly Kuznetsov1-0/+3
Some host adapters (e.g. Hyper-V storvsc) are known for not respecting the SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall contain at least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1: scsi scan: INQUIRY result too short (5), using 36' messages on console. This can be problematic for slow consoles. Introduce short_inquiry flag in struct Scsi_Host to print the message once per host. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-11-09scsi: use host wide tags by defaultChristoph Hellwig1-5/+0
This patch changes the !blk-mq path to the same defaults as the blk-mq I/O path by always enabling block tagging, and always using host wide tags. We've had blk-mq available for a few releases so bugs with this mode should have been ironed out, and this ensures we get better coverage of over tagging setup over different configs. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-01-23block: support different tag allocation policyShaohua Li1-0/+3
The libata tag allocation is using a round-robin policy. Next patch will make libata use block generic tag allocation, so let's add a policy to tag allocation. Currently two policies: FIFO (default) and round-robin. Cc: Jens Axboe <axboe@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-12-18Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linusJames Bottomley1-13/+0
2014-12-12Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-1/+1
Pull trivial tree update from Jiri Kosina: "Usual stuff: documentation updates, printk() fixes, etc" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits) intel_ips: fix a type in error message cpufreq: cpufreq-dt: Move newline to end of error message ps3rom: fix error return code treewide: fix typo in printk and Kconfig ARM: dts: bcm63138: change "interupts" to "interrupts" Replace mentions of "list_struct" to "list_head" kernel: trace: fix printk message scsi: mpt2sas: fix ioctl in comment zbud, zswap: change module author email clocksource: Fix 'clcoksource' typo in comment arm: fix wording of "Crotex" in CONFIG_ARCH_EXYNOS3 help gpio: msm-v1: make boolean argument more obvious usb: Fix typo in usb-serial-simple.c PCI: Fix comment typo 'COMFIG_PM_OPS' powerpc: Fix comment typo 'CONIFG_8xx' powerpc: Fix comment typos 'CONFiG_ALTIVEC' clk: st: Spelling s/stucture/structure/ isci: Spelling s/stucture/structure/ usb: gadget: zero: Spelling s/infrastucture/infrastructure/ treewide: Fix company name in module descriptions ...
2014-12-04scsi: remove ->change_queue_type methodChristoph Hellwig1-13/+0
Since we got rid of ordered tag support in 2010 the prime use case of switching on and off ordered tags has been obsolete. The other function of enabling/disabling tagging entirely has only been correctly implemented by the 53c700 driver and isn't generally useful. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24scsi: drop reason argument from ->change_queue_depthChristoph Hellwig1-6/+2
Drop the now unused reason argument from the ->change_queue_depth method. Also add a return value to scsi_adjust_queue_depth, and rename it to scsi_change_queue_depth now that it can be used as the default ->change_queue_depth implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-24scsi: avoid ->change_queue_depth indirection for queue full trackingChristoph Hellwig1-2/+5
All drivers use the implementation for ramping the queue up and down, so instead of overloading the change_queue_depth method call the implementation diretly if the driver opts into it by setting the track_queue_depth flag in the host template. Note that a few drivers validated the new queue depth in their change_queue_depth method, but as we never go over the queue depth set during slave_configure or the sysfs file this isn't nessecary and can safely be removed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
2014-11-20Merge Linus' tree to be be to apply submitted patches to newer code thanJiri Kosina1-1/+5
current trivial.git base
2014-11-12scsi: always assign block layer tags if enabledChristoph Hellwig1-0/+5
Allow a driver to ask for block layer tags by setting .use_blk_tags in the host template, in which case it will always see a valid value in request->tag, similar to the behavior when using blk-mq. This means even SCSI "untagged" commands will now have a tag, which is especially useful when using a host-wide tag map. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: remove use_blk_tcq Scsi_Host fieldChristoph Hellwig1-1/+0
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-11-12scsi: remove ordered_tag host template fieldChristoph Hellwig1-10/+0
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: add support for multiple hardware queuesBart Van Assche1-0/+8
Allow a SCSI LLD to declare how many hardware queues it supports by setting Scsi_Host.nr_hw_queues before calling scsi_add_host(). Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-29scsi: Fix "choir" and "beeing" malapropsFinn Thain1-1/+1
Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-09-30scsi: fix comment in struct Scsi_Host definitionSebastian Herbszt1-1/+1
Commit 1abf635 (scsi: use 64-bit value for 'max_luns') changed the order of Scsi_Host members. Update the comment to reflect this. Signed-off-by: Sebastian Herbszt <herbszt@gmx.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-15scsi: don't store LUN bits in CDB[1] for USB mass-storage devicesAlan Stern1-0/+3
The SCSI specification requires that the second Command Data Byte should contain the LUN value in its high-order bits if the recipient device reports SCSI level 2 or below. Nevertheless, some USB mass-storage devices use those bits for other purposes in vendor-specific commands. Currently Linux has no way to send such commands, because the SCSI stack always overwrites the LUN bits. Testing shows that Windows 7 and XP do not store the LUN bits in the CDB when sending commands to a USB device. This doesn't matter if the device uses the Bulk-Only or UAS transports (which virtually all modern USB mass-storage devices do), as these have a separate mechanism for sending the LUN value. Therefore this patch introduces a flag in the Scsi_Host structure to inform the SCSI midlayer that a transport does not require the LUN bits to be stored in the CDB, and it makes usb-storage set this flag for all devices using the Bulk-Only transport. (UAS is handled by a separate driver, but it doesn't really matter because no SCSI-2 or lower device is at all likely to use UAS.) The patch also cleans up the code responsible for storing the LUN value by adding a bitflag to the scsi_device structure. The test for whether to stick the LUN value in the CDB can be made when the device is probed, and stored for future use rather than being made over and over in the fast path. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Tiziano Bacocco <tiziano.bacocco@gmail.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-15scsi: add use_cmd_list flagKashyap.Desai@avagotech.com1-0/+1
Add a use_cmd_list flag in struct Scsi_Host to request keeping track of all outstanding commands per device. Default behaviour is not to keep track of cmd_list per sdev, as this may introduce lock contention. (overhead is more on multi-node NUMA.), and only enable it on the two drivers that need it. Signed-off-by: Kashyap Desai <kashyap.desai@avagotech.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25scsi: add support for a blk-mq based I/O path.Christoph Hellwig1-1/+17
This patch adds support for an alternate I/O path in the scsi midlayer which uses the blk-mq infrastructure instead of the legacy request code. Use of blk-mq is fully transparent to drivers, although for now a host template field is provided to opt out of blk-mq usage in case any unforseen incompatibilities arise. In general replacing the legacy request code with blk-mq is a simple and mostly mechanical transformation. The biggest exception is the new code that deals with the fact the I/O submissions in blk-mq must happen from process context, which slightly complicates the I/O completion handler. The second biggest differences is that blk-mq is build around the concept of preallocated requests that also include driver specific data, which in SCSI context means the scsi_cmnd structure. This completely avoids dynamic memory allocations for the fast path through I/O submission. Due the preallocated requests the MQ code path exclusively uses the host-wide shared tag allocator instead of a per-LUN one. This only affects drivers actually using the block layer provided tag allocator instead of their own. Unlike the old path blk-mq always provides a tag, although drivers don't have to use it. For now the blk-mq path is disable by defauly and must be enabled using the "use_blk_mq" module parameter. Once the remaining work in the block layer to make blk-mq more suitable for slow devices is complete I hope to make it the default and eventually even remove the old code path. Based on the earlier scsi-mq prototype by Nicholas Bellinger. Thanks to Bart Van Assche and Robert Elliot for testing, benchmarking and various sugestions and code contributions. 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: fix the {host,target,device}_blocked counter messChristoph Hellwig1-5/+2
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 host_busy to atomic_tChristoph Hellwig1-7/+3
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>
2014-07-17scsi: remove various exports that were only used by scsi_tgtChristoph Hellwig1-2/+0
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17tgt: removalBart Van Assche1-21/+0
Now that the ibmvstgt driver as the only user of scsi_tgt is gone, the scsi_tgt kernel module, the CONFIG_SCSI_TGT, CONFIG_SCSI_SRP_TGT_ATTRS and CONFIG_SCSI_FC_TGT_ATTRS kbuild variable, the scsi_host_template transfer_response method are no longer needed. [hch: minor updates to the current tree, changelog update] Signed-off-by: Bart Van Assche <bvanassche@acm.org> 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 64-bit value for 'max_luns'Hannes Reinecke1-3/+3
Now that we're using 64-bit LUNs internally we need to increase the size of max_luns to 64 bits, too. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ewan Milne <emilne@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17scsi: increase upper limit for max_sectorsAkinobu Mita1-2/+2
max_sectors in struct Scsi_Host specifies maximum number of sectors allowed in a single SCSI command. The data type of max_sectors is unsigned short, so the maximum transfer length per SCSI command is limited to less than 256MB in 4096-bytes sector size. (0xffff * 4096) This commit increases the SCSI mid level's limitation for max_sectors upto the block layer's limitation for max_hw_sectors by extending the data type of max_sectors in struct Scsi_Host and scsi_host_template, so that SCSI lower level drivers can specify more than 0xffff. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-03-27[SCSI] add support for per-host cmd poolsChristoph Hellwig1-0/+7
This allows drivers to specify the size of their per-command private data in the host template and then get extra memory allocated for each command instead of needing another allocation in ->queuecommand. With the current SCSI code that already does multiple allocations for each command this probably doesn't make a big performance impact, but it allows to clean up the drivers, and prepare them for using the blk-mq infrastructure where the common allocation will make a difference. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-12-19[SCSI] improved eh timeout handlerHannes Reinecke1-0/+10
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>
2013-11-29[SCSI] Disable WRITE SAME for RAID and virtual host adapter driversMartin K. Petersen1-0/+6
Some host adapters do not pass commands through to the target disk directly. Instead they provide an emulated target which may or may not accurately report its capabilities. In some cases the physical device characteristics are reported even when the host adapter is processing commands on the device's behalf. This can lead to adapter firmware hangs or excessive I/O errors. This patch disables WRITE SAME for devices connected to host adapters that provide an emulated target. Driver writers can disable WRITE SAME by setting the no_write_same flag in the host adapter template. [jejb: fix up rejections due to eh_deadline patch] Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: stable@kernel.org Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-10-25[SCSI] Add 'eh_deadline' to limit SCSI EH runtimeHannes Reinecke1-0/+5
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>
2013-10-25[SCSI] remove check for 'resetting'Hannes Reinecke1-2/+0
Field is now unused, so this is dead code. [jejb: remove resetting and last_reset from Scsi_Host] Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-09scsi: bury ->proc_info()Al Viro1-2/+1
all users converted to ->show_info()/->write_info() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09scsi: saner replacements for ->proc_info()Al Viro1-1/+4
It's still an obsolete interface; don't introduce those in new drivers. However, it's saner than the ->proc_info() and commits after this one will convert the existing ->proc_info() users to it. The read side is ->show_info(seq_file *, struct Scsi_Host *); use seq_... for generating contents. The write side is ->write_info(struct Scsi_Host *, char *, int). Again, this is driven by procfs needs; we are going to kill ->write_proc() and ->read_proc() and this is the main obstacle to burying that piece of shit. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-24[SCSI] Fix range check in scsi_host_dif_capable()Martin K. Petersen1-2/+2
The range checking from fe542396 was bad. We would still end up walking beyond the array as Type 3 is defined to be 4 in the protection bitmask. Instead use ARRAY_SIZE() for the range check. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24[SCSI] sd: Ensure we correctly disable devices with unknown protection typeMartin K. Petersen1-0/+6
We set the capacity to zero when we discovered a device formatted with an unknown DIF protection type. However, the read_capacity code would override the capacity and cause the device to be enabled regardless. Make sd_read_protection_type() return an error if the protection type is unknown. Also prevent duplicate printk lines when the device is being revalidated. Reported-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-08[SCSI] add flag to skip the runtime PM calls on the hostLin Ming1-0/+3
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>
2011-08-29[SCSI] scsi scan: don't fail scans when host is in recoveryMike Christie1-1/+2
The problem is that if we are doing a scsi scan then the device goes into recovery then we will wait for the recovery to complete. It waits because scsi-ml will send inquiries or report luns and the queueing code will have been blocked due to the host not being ready. However, if we are in recovery and then a scan is started the scan will silently fail and some devices will not be added. It is easy to hit the problem where devices do not show up with FC where we are doing tests that disrupt the target controllers. When the controller is disruprted (reboot, or setting firmware, etc), and we cause the dev loss tmo to fire then devices will be removed Then when the problem has been fixed, the rport will be scanned and devices should be added back. But if we cause another disruption before scanning has started then devices will not get added back. If the problem is not started until the scan is started then the devices will be added back. This patch fixes that problem by not failing scans when the host is in recovery. We will let scsi-ml send the IO and let the queueing and scsi error handling deal with it like is done if we went into recovery while scanning. For recovery cases where the host is being torn down then with the patch we will still fail the scan since there is not point in scanning. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-27[SCSI] scsi: Added support for adapter and firmware resetVikas Chaudhary1-0/+13
Added new sysfs attr 'host_reset' in scsi_sysfs.c to perform adapter or firmware reset as suggested by Mike Christie here: http://marc.info/?l=linux-scsi&m=127359347111167&w=2 user/application can write "adapter" or "firmware" on this attr and it will call newly added function hook in scsi_host_template to call LDD adapter or firmware reset implementation. Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-11-16SCSI host lock push-downJeff Garzik1-2/+21
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>
2010-09-10block/scsi: Provide a limit on the number of integrity segmentsMartin K. Petersen1-0/+7
Some controllers have a hardware limit on the number of protection information scatter-gather list segments they can handle. Introduce a max_integrity_segments limit in the block layer and provide a new scsi_host_template setting that allows HBA drivers to provide a value suitable for the hardware. Add support for honoring the integrity segment limit when merging both bios and requests. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>