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2014-07-25mptfusion: use memdup_userJoe Lawrence1-13/+5
Let memdup_user handle the kmalloc, copy_from_user and error checking kfree code. Spotted by the following smatch (false positive) warning: drivers/message/fusion/mptctl.c:1369 mptctl_getiocinfo() warn: possible info leak 'karg' Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mptfusion: remove redundant kfree checksJoe Lawrence2-4/+2
Fixes the following smatch warnings: drivers/message/fusion/mptfc.c:529 mptfc_target_destroy() info: redundant null check on starget->hostdata calling kfree() drivers/message/fusion/mptspi.c:465 mptspi_target_destroy() info: redundant null check on starget->hostdata calling kfree() Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mptfusion: mark file-private functions as staticJoe Lawrence3-5/+5
Fixes the following sparse warnings: drivers/message/fusion/mptbase.c:7011:1: warning: symbol 'mpt_SoftResetHandler' was not declared. Should it be static? drivers/message/fusion/mptsas.c:1578:23: warning: symbol 'mptsas_refreshing_device_handles' was not declared. Should it be static? drivers/message/fusion/mptsas.c:3653:24: warning: symbol 'mptsas_expander_add' was not declared. Should it be static? drivers/message/fusion/mptsas.c:5327:1: warning: symbol 'mptsas_shutdown' was not declared. Should it be static? drivers/message/fusion/mptspi.c:624:1: warning: symbol 'mptscsih_quiesce_raid' was not declared. Should it be static? Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mpt3sas: combine fw_event_work and its event_dataJoe Lawrence1-25/+31
Tack the firmware reply event_data payload to the end of its corresponding struct fw_event_work allocation. This matches the convention in the mptfusion driver and simplifies the code. This avoids the following smatch warning: drivers/scsi/mpt3sas/mpt3sas_scsih.c:2519 mpt3sas_send_trigger_data_event() warn: possible memory leak of 'fw_event' Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mpt3sas: correct scsi_{target,device} hostdata allocationJoe Lawrence1-2/+4
In _scsih_{slave,target}_alloc, an incorrect structure type is passed to sizeof() when allocating storage for hostdata. Luckily larger structure types were used, so at least the wrong sizes were safe: struct scsi_device (1784 bytes) > struct MPT3SAS_DEVICE (24 bytes) struct scsi_target (760 bytes) > struct MPT3SAS_TARGET (32 bytes) This fixes the following smatch warnings: drivers/scsi/mpt3sas/mpt3sas_scsih.c:1166 _scsih_target_alloc() warn: struct type mismatch 'MPT3SAS_TARGET vs scsi_target' drivers/scsi/mpt3sas/mpt3sas_scsih.c:1280 _scsih_slave_alloc() warn: struct type mismatch 'MPT3SAS_DEVICE vs scsi_device' Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mpt2sas: annotate ioc->reply_post_host_index as __iomemJoe Lawrence2-5/+6
The MPT2SAS_ADAPTER reply_post_host_index[] holds calculated addresses in memory mapped register space. Add an "__iomem" annotation to silence the following sparse warnings: drivers/scsi/mpt2sas/mpt2sas_base.c:1006:43: warning: incorrect type in argument 2 (different address spaces) expected void volatile [noderef] <asn:2>*addr got unsigned long long [usertype] *<noident> drivers/scsi/mpt2sas/mpt2sas_base.c:4299:22: warning: cast removes address space of expression drivers/scsi/mpt2sas/mpt2sas_base.c:4303:27: warning: cast removes address space of expression Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mpt2sas: combine fw_event_work and its event_dataJoe Lawrence1-22/+30
Tack the firmware reply event_data payload to the end of its corresponding struct fw_event_work allocation. This matches the convention in the mptfusion driver and simplifies the code. Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25mpt2sas: correct scsi_{target,device} hostdata allocationJoe Lawrence1-2/+4
In _scsih_{slave,target}_alloc, an incorrect structure type is passed to sizeof() when allocating storage for hostdata. Luckily larger structure types were used, so at least the wrong sizes were safe: struct scsi_device (1784 bytes) > struct MPT2SAS_DEVICE (24 bytes) struct scsi_target (760 bytes) > struct MPT2SAS_TARGET (40 bytes) This fixes the following smatch warnings: drivers/scsi/mpt2sas/mpt2sas_scsih.c:1295 _scsih_target_alloc() warn: struct type mismatch 'MPT2SAS_TARGET vs scsi_target' drivers/scsi/mpt2sas/mpt2sas_scsih.c:1409 _scsih_slave_alloc() warn: struct type mismatch 'MPT2SAS_DEVICE vs scsi_device' Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-253w-xxxx: fix mis-aligned struct accessesArnd Bergmann1-2/+2
Building an allmodconfig ARM kernel, I get multiple such warnings because of a spinlock contained in packed structure in the 3w-xxxx driver: ../drivers/scsi/3w-xxxx.c: In function 'tw_chrdev_ioctl': ../drivers/scsi/3w-xxxx.c:1001:68: warning: mis-aligned access used for structure member [-fstrict-volatile-bitfields] timeout = wait_event_timeout(tw_dev->ioctl_wqueue, tw_dev->chrdev_request_id == TW_IOCTL_CHRDEV_FREE, timeout); ^ ../drivers/scsi/3w-xxxx.c:1001:68: note: when a volatile object spans multiple type-sized locations, the compiler must choose between using a single mis-aligned access to preserve the volatility, or using multiple aligned accesses to avoid runtime faults; this code may fail at runtime if the hardware does not allow this access The same bug apparently was present in 3w-sas and 3w-9xxx, but has been fixed in the past. This patch uses the same fix by moving the pragma in front of the TW_Device_Extension definition, so it only covers hardware structures. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Adam Radford <aradford@gmail.com> Cc: Adam Radford <linuxraid@lsi.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25NCR53c406a: don't call free_dma() by defaultArnd Bergmann1-1/+1
The NCR53c406a scsi driver normally does not use DMA, unless the USE_PIO macro is disabled by modifying the source code. The call to free_dma() for some reason uses #ifdef USE_DMA, which does not do the right thing, since USE_DMA is defined as a boolean that is either 0 or 1, but always present. One case where it gets in the way is randconfig builds on ARM, which depending on the configuration does not provide a free_dma() function, causing this build error: drivers/scsi/NCR53c406a.c: In function 'NCR53c406a_release': drivers/scsi/NCR53c406a.c:600:3: error: implicit declaration of function 'free_dma' [-Werror=implicit-function-declaration] free_dma(shost->dma_channel); ^ This changes the code to use #if USE_DMA, to match the rest of the file, which seems to be what the author intended. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25qlogicfas: don't call free_dma()Arnd Bergmann1-2/+0
The qlogicfas scsi driver does not use DMA, and the call to free_dma() in its exit function seems to have been copied incorrectly from another driver but never caused trouble. One case where it gets in the way is randconfig builds on ARM, which depending on the configuration does not provide a free_dma() function, causing this build error: drivers/scsi/qlogicfas.c: In function 'qlogicfas_release': drivers/scsi/qlogicfas.c:175:3: error: implicit declaration of function 'free_dma' [-Werror=implicit-function-declaration] free_dma(shost->dma_channel); ^ Removing the incorrect function calls should be the obvious fix for this, with no downsides. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25pas16: don't call free_dma()Arnd Bergmann1-2/+0
The pas16 scsi driver does not use DMA, and the call to free_dma() in its exit function seems to have been copied incorrectly from another driver but never caused trouble. One case where it gets in the way is randconfig builds on ARM, which depending on the configuration does not provide a free_dma() function, causing this build error: drivers/scsi/pas16.c: In function 'pas16_release': drivers/scsi/pas16.c:611:3: error: implicit declaration of function 'free_dma' [-Werror=implicit-function-declaration] free_dma(shost->dma_channel); Removing the incorrect function calls should be the obvious fix for this, with no downsides. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25advansys: don't build ARMArnd Bergmann1-1/+1
The advansys SCSI driver uses the dma_cache_sync function, which is not available on the ARM architecture, and cannot be implemented correctly, so we always get this build error: drivers/scsi/advansys.c: In function 'advansys_get_sense_buffer_dma': drivers/scsi/advansys.c:7882:2: error: implicit declaration of function 'dma_cache_sync' [-Werror=implicit-function-declaration] dma_cache_sync(board->dev, scp->sense_buffer, ^ It seems nobody has missed this driver so far, so let's just disable it for ARM to help randconfig builds. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25ibmvfc: fix little endian issuesTyrel Datwyler2-367/+374
Added big endian annotations to relevant data structure fields, and necessary byte swappings to support little endian builds. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25qla2xxx: Use dma_zalloc_coherentJoe Perches1-6/+4
Use the zeroing function instead of dma_alloc_coherent & memset(,0,) Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Saurav Kashyap <saurav.kashyap@qlogic.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25bfa: use ARRAY_SIZE instead of sizeof/sizeof[0]Fabian Frederick1-3/+3
Use macro definition Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Anil Gurumurthy <anil.gurumurthy@qlogic.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25bfa: remove useless return variablesPeter Senna Tschudin1-6/+4
This patch remove variables that are initialized with a constant, are never updated, and are only used as parameter of return. Return the constant instead of using a variable. Verified by compilation only. The coccinelle script that find and fixes this issue is: // <smpl> @@ type T; constant C; identifier ret; @@ - T ret = C; ... when != ret when strict return - ret + C ; // </smpl> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Sudarsana Kalluru <Sudarsana.Kalluru@qlogic.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25bfa: Fix undefined bit shift on big-endian architectures with 32-bit DMA addressBen Hutchings1-1/+1
bfa_swap_words() shifts its argument (assumed to be 64-bit) by 32 bits each way. In two places the argument type is dma_addr_t, which may be 32-bit, in which case the effect of the bit shift is undefined: drivers/scsi/bfa/bfa_fcpim.c: In function 'bfa_ioim_send_ioreq': drivers/scsi/bfa/bfa_fcpim.c:2497:4: warning: left shift count >= width of type [enabled by default] addr = bfa_sgaddr_le(sg_dma_address(sg)); ^ drivers/scsi/bfa/bfa_fcpim.c:2497:4: warning: right shift count >= width of type [enabled by default] drivers/scsi/bfa/bfa_fcpim.c:2509:4: warning: left shift count >= width of type [enabled by default] addr = bfa_sgaddr_le(sg_dma_address(sg)); ^ drivers/scsi/bfa/bfa_fcpim.c:2509:4: warning: right shift count >= width of type [enabled by default] Avoid this by adding casts to u64 in bfa_swap_words(). Compile-tested only. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Anil Gurumurthy <anil.gurumurthy@qlogic.com> Cc: stable@vger.kernel.org Fixes: f16a17507b09 ('[SCSI] bfa: remove all OS wrappers') Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25bfa: Use dma_zalloc_coherentJoe Perches1-3/+3
Use the zeroing function instead of dma_alloc_coherent & memset(,0,) Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Anil Gurumurthy <anil.gurumurthy@qlogic.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25aic7xxx: Use kstrdupHimangi Saraogi3-6/+3
Use kstrdup when the goal of an allocation is copy a string into the allocated region. The Coccinelle semantic patch that makes this change is as follows: // <smpl> @@ expression from,to; expression flag,E1,E2; statement S; @@ - to = kmalloc(strlen(from) + 1,flag); + to = kstrdup(from, flag); ... when != \(from = E1 \| to = E1 \) if (to==NULL || ...) S ... when != \(from = E2 \| to = E2 \) - strcpy(to, from); // </smpl> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> Acked-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25scsi: add defines for new FC port speeds.Dick Kennedy2-0/+8
These speeds are to support the next generation of FCoE port speeds. Signed-off-by: Dick Kennedy <Dick.Kennedy@Emulex.Com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25bnx2i, be2iscsi: fix custom stats lengthMike Christie2-5/+4
The custom stats is an array with custom_length indicating the length of the array. This patch fixes bnx2i and be2iscsi's setting of the custom stats length. They both just have the one, eh_abort_cnt, so that should be in the first entry of the custom array and custom_length should then be one. Reported-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com> Acked-by: Eddie Wai <eddie.wai@broadcom.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25iscsi: kill redundant castsNick Black' via open-iscsi1-2/+2
Remove two redundant casts from char * to char *. Signed-off-by: Nick Black <nlb@google.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25tgt: remove SCSI_TGT and SCSI_FC_TGT_ATTRSPaul Bolle1-14/+0
The Kconfig symbols SCSI_TGT and SCSI_FC_TGT_ATTRS are unused since "tgt: removal". Setting them has no effect. Remove these symbols. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25sd: fix a bug in deriving the FLUSH_TIMEOUT from the basic I/O timeoutK. Y. Srinivasan1-1/+1
Commit ID: 7e660100d85af860e7ad763202fff717adcdaacd added code to derive the FLUSH_TIMEOUT from the basic I/O timeout. However, this patch did not use the basic I/O timeout of the device. Fix this bug. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25scsi: add a blacklist flag which enables VPD page inquiriesMartin K. Petersen4-1/+10
Despite supporting modern SCSI features some storage devices continue to claim conformance to an older version of the SPC spec. This is done for compatibility with legacy operating systems. Linux by default will not attempt to read VPD pages on devices that claim SPC-2 or older. Introduce a blacklist flag that can be used to trigger VPD page inquiries on devices that are known to support them. Reported-by: KY Srinivasan <kys@microsoft.com> Tested-by: KY Srinivasan <kys@microsoft.com> Reviewed-by: KY Srinivasan <kys@microsoft.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> CC: <stable@vger.kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-25scsi: move the writeable field from struct scsi_device to struct scsi_cdChristoph Hellwig5-30/+3
We currently set the field in common code based on the device type, but then only use it in the cdrom driver which also overrides the value previously set in the generic code. Just leave this entirely to the CDROM driver to make everyones life simpler. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-07-25scsi: add a symbolic name for the ZBC device typeChristoph Hellwig1-0/+1
Make sure we have a symbolic name for the ZBC type available, so that e.g. patch for a SATA to translate ZAC commands can make use of it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-07-25scsi: update scsi_device_typesChristoph Hellwig1-0/+2
Add two new device types, most importantly the zoned block device one. Split from an earlier patch by Hannes Reinecke. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-07-25fnic: reject device resets without assigned tags for the blk-mq caseChristoph Hellwig1-0/+16
Current the midlayer fakes up a struct request for the explicit reset ioctls, and those don't have a tag allocated to them. The fnic driver pokes into midlayer structures to paper over this design issue, but that won't work for the blk-mq case. Either someone who can actually test the hardware will have to come up with a similar hack for the blk-mq case, or we'll have to bite the bullet and fix the way the EH ioctls work for real, but until that happens we fail these explicit requests here. 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> Cc: Hiral Patel <hiralpat@cisco.com> Cc: Suma Ramars <sramars@cisco.com> Cc: Brian Uchino <buchino@cisco.com>
2014-07-25scsi: add support for a blk-mq based I/O path.Christoph Hellwig8-72/+488
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>
2014-07-25scatterlist: allow chaining to preallocated chunksChristoph Hellwig3-20/+27
Blk-mq drivers usually preallocate their S/G list as part of the request, but if we want to support the very large S/G lists currently supported by the SCSI code that would tie up a lot of memory in the preallocated request pool. Add support to the scatterlist code so that it can initialize a S/G list that uses a preallocated first chunks and dynamically allocated additional chunks. That way the scsi-mq code can preallocate a first page worth of S/G entries as part of the request, and dynamically extend the S/G list when needed. 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: unwind blk_end_request_all and blk_end_request_err callsChristoph Hellwig1-19/+42
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 Hellwig1-10/+18
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 Hellwig5-53/+58
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 Hellwig5-28/+40
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 Hellwig9-48/+69
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 Hellwig2-23/+34
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 Hellwig1-36/+39
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 Hellwig2-22/+21
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 Hellwig2-26/+18
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 Hellwig1-18/+26
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 Hellwig1-18/+22
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 Hellwig2-4/+1
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sd: split sd_init_commandChristoph Hellwig1-29/+29
Factor out a function to initialize regular read/write commands and leave sd_init_command as a simple dispatcher to the different prepare routines. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sd: retry discard commandsChristoph Hellwig1-1/+1
Currently cmd->allowed is initialized from rq->retries for discard commands, but retries is always 0 for non-BLOCK_PC requests. Set it to the standard number of retries instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sd: retry write same commandsChristoph Hellwig1-1/+1
Currently cmd->allowed is initialized from rq->retries for write same commands, but retries is always 0 for non-BLOCK_PC requests. Set it to the standard number of retries instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sd: don't use scsi_setup_blk_pc_cmnd for discard requestsChristoph Hellwig1-19/+31
Simplify handling of discard requests by setting up the command directly instead of initializing request fields and then calling scsi_setup_blk_pc_cmnd to propagate the information into the command. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sd: don't use scsi_setup_blk_pc_cmnd for write same requestsChristoph Hellwig1-16/+28
Simplify handling of write same requests by setting up the command directly instead of initializing request fields and then calling scsi_setup_blk_pc_cmnd to propagate the information into the command. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Webb Scales <webbnh@hp.com>
2014-07-17sd: don't use scsi_setup_blk_pc_cmnd for flush requestsChristoph Hellwig1-7/+13
Simplify handling of flush requests by setting up the command directly instead of initializing request fields and then calling scsi_setup_blk_pc_cmnd to propagate the information into the command. Also rename scsi_setup_flush_cmnd to sd_setup_flush_cmnd for consistency. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>