Commit Graph

138 Commits

Author SHA1 Message Date
Chaotian Jing
f03e94f23b scsi: core: Fix the return value of scsi_logical_block_count()
scsi_logical_block_count() should return the block count of a given SCSI
command. The original implementation ended up shifting twice, leading to an
incorrect count being returned. Fix the conversion between bytes and
logical blocks.

Cc: stable@vger.kernel.org
Fixes: 6a20e21ae1 ("scsi: core: Add helper to return number of logical blocks in a request")
Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Link: https://lore.kernel.org/r/20240813053534.7720-1-chaotian.jing@mediatek.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2024-08-16 21:02:06 -04:00
Randy Dunlap
fcf8829fd9 scsi: core: Add kernel-doc for scsi_msg_to_host_byte()
Add entries for missing documentation to prevent kernel-doc warnings:

scsi_cmnd.h:365: warning: Function parameter or struct member 'cmd' not described in 'scsi_msg_to_host_byte'
scsi_cmnd.h:365: warning: Function parameter or struct member 'msg' not described in 'scsi_msg_to_host_byte'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20240408025425.18778-4-rdunlap@infradead.org
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2024-04-08 22:10:06 -04:00
Niklas Cassel
3d848ca1eb scsi: core: Allow libata to complete successful commands via EH
In SCSI, we get the sense data as part of the completion, for ATA however,
we need to fetch the sense data as an extra step. For an aborted ATA
command the sense data is fetched via libata's ->eh_strategy_handler().

For Command Duration Limits policy 0xD:

  The device shall complete the command without error with the additional
  sense code set to DATA CURRENTLY UNAVAILABLE.

In order to handle this policy in libata, we intend to send a successful
command via SCSI EH, and let libata's ->eh_strategy_handler() fetch the
sense data for the good command. This is similar to how we handle an
aborted ATA command, just that we need to read the Successful NCQ Commands
log instead of the NCQ Command Error log.

When we get a SATA completion with successful commands, ATA_SENSE will be
set, indicating that some commands in the completion have sense data.

The sense_valid bitmask in the Sense Data for Successful NCQ Commands log
will inform exactly which commands that had sense data, which might be a
subset of all the commands that was completed in the same completion. (Yet
all will have ATA_SENSE set, since the status is per completion.)

The successful commands that have e.g. a "DATA CURRENTLY UNAVAILABLE" sense
data will have a SCSI ML byte set, so scsi_eh_flush_done_q() will not set
the scmd->result to DID_TIME_OUT for these commands. However, the
successful commands that did not have sense data, must not get their result
marked as DID_TIME_OUT by SCSI EH.

Add a new flag SCMD_FORCE_EH_SUCCESS, which tells SCSI EH to not mark a
command as DID_TIME_OUT, even if it has scmd->result == SAM_STAT_GOOD.

This will be used by libata in a subsequent commit.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Link: https://lore.kernel.org/r/20230511011356.227789-5-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-05-22 17:05:18 -04:00
Bart Van Assche
310bcaef6d scsi: core: Support failing requests while recovering
The current behavior for SCSI commands submitted while error recovery is
ongoing is to retry command submission after error recovery has finished.
See also the scsi_host_in_recovery() check in scsi_host_queue_ready(). Add
support for failing SCSI commands while host recovery is in progress. This
functionality will be used to fix a deadlock in the UFS driver.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221018202958.1902564-4-bvanassche@acm.org
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-10-22 03:25:59 +00:00
Linus Torvalds
6022f21046 scsi: stex: Properly zero out the passthrough command structure
The passthrough structure is declared off of the stack, so it needs to be
set to zero before copied back to userspace to prevent any unintentional
data leakage.  Switch things to be statically allocated which will fill the
unused fields with 0 automatically.

Link: https://lore.kernel.org/r/YxrjN3OOw2HHl9tx@kroah.com
Cc: stable@kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: hdthky <hdthky0@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-09-25 14:15:03 -04:00
Bart Van Assche
ea957547e8 scsi/core: Improve static type checking
Improve static type checking by using the new blk_opf_t type for the
combination of a request operation and its flags.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.garry@huawei.com>
Cc: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-40-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:32 -06:00
Linus Torvalds
6f2689a766 SCSI misc on 20220324
This series consists of the usual driver updates (qla2xxx, pm8001,
 libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
 and bug fixes.  The high blast radius core update is the removal of
 write same, which affects block and several non-SCSI devices.  The
 other big change, which is more local, is the removal of the SCSI
 pointer.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This series consists of the usual driver updates (qla2xxx, pm8001,
  libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
  and bug fixes.

  The high blast radius core update is the removal of write same, which
  affects block and several non-SCSI devices. The other big change,
  which is more local, is the removal of the SCSI pointer"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (281 commits)
  scsi: scsi_ioctl: Drop needless assignment in sg_io()
  scsi: bsg: Drop needless assignment in scsi_bsg_sg_io_fn()
  scsi: lpfc: Copyright updates for 14.2.0.0 patches
  scsi: lpfc: Update lpfc version to 14.2.0.0
  scsi: lpfc: SLI path split: Refactor BSG paths
  scsi: lpfc: SLI path split: Refactor Abort paths
  scsi: lpfc: SLI path split: Refactor SCSI paths
  scsi: lpfc: SLI path split: Refactor CT paths
  scsi: lpfc: SLI path split: Refactor misc ELS paths
  scsi: lpfc: SLI path split: Refactor VMID paths
  scsi: lpfc: SLI path split: Refactor FDISC paths
  scsi: lpfc: SLI path split: Refactor LS_RJT paths
  scsi: lpfc: SLI path split: Refactor LS_ACC paths
  scsi: lpfc: SLI path split: Refactor the RSCN/SCR/RDF/EDC/FARPR paths
  scsi: lpfc: SLI path split: Refactor PLOGI/PRLI/ADISC/LOGO paths
  scsi: lpfc: SLI path split: Refactor base ELS paths and the FLOGI path
  scsi: lpfc: SLI path split: Introduce lpfc_prep_wqe
  scsi: lpfc: SLI path split: Refactor fast and slow paths to native SLI4
  scsi: lpfc: SLI path split: Refactor lpfc_iocbq
  scsi: lpfc: Use kcalloc()
  ...
2022-03-24 19:37:53 -07:00
Christoph Hellwig
e7f7655227 scsi: don't use disk->private_data to find the scsi_driver
Requiring every ULP to have the scsi_drive as first member of the
private data is rather fragile and not necessary anyway.  Just use
the driver hanging off the SCSI device instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220308055200.735835-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-08 19:40:00 -07:00
Christoph Hellwig
2644030331 scsi: core: Remove <scsi/scsi_request.h>
This header is empty now except for an include of <linux/blk-mq.h>, so
remove it.

Link: https://lore.kernel.org/r/20220224175552.988286-9-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 22:21:50 -05:00
Christoph Hellwig
6aded12b10 scsi: core: Remove struct scsi_request
Let submitters initialize the scmd->allowed field directly instead of
indirecting through struct scsi_request and remove the now superfluous
structure.

Link: https://lore.kernel.org/r/20220224175552.988286-8-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 22:21:50 -05:00
Christoph Hellwig
a9a4ea1166 scsi: core: Move the resid_len field from struct scsi_request to struct scsi_cmnd
Prepare for removing the scsi_request structure by moving the resid_len
field to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-6-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 22:21:49 -05:00
Christoph Hellwig
5b794f9807 scsi: core: Remove the sense and sense_len fields from struct scsi_request
Just use the sense_buffer field in struct scsi_cmnd for the sense data and
move the sense_len field over to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-5-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 22:21:49 -05:00
Christoph Hellwig
ce70fd9a55 scsi: core: Remove the cmd field from struct scsi_request
Now that each scsi_request is backed by a scsi_cmnd, there is no need to
indirect the CDB storage.  Change all submitters of SCSI passthrough
requests to store the CDB information directly in the scsi_cmnd, and while
doing so allocate the full 32 bytes that cover all Linux supported SCSI
hosts instead of requiring dynamic allocation for > 16 byte CDBs.  On
64-bit systems this does not change the size of the scsi_cmnd at all, while
on 32-bit systems it slightly increases it for now, but that increase will
be made up by the removal of the remaining scsi_request fields.

Link: https://lore.kernel.org/r/20220224175552.988286-4-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 22:21:49 -05:00
Bart Van Assche
8264aee803 scsi: core: Remove struct scsi_pointer from struct scsi_cmnd
Remove struct scsi_pointer from struct scsi_cmnd since the previous patches
removed all users of that member of struct scsi_cmnd. Additionally, reorder
the members of struct scsi_cmnd such that the statement that the field
below can be modified by the SCSI LLD is again correct.

Link: https://lore.kernel.org/r/20220218195117.25689-50-bvanassche@acm.org
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-02-22 21:11:07 -05:00
Sebastian Andrzej Siewior
b84b6ec0f9 scsi: core: Add scsi_done_direct() for immediate completion
Add scsi_done_direct() which behaves like scsi_done() except that it
invokes blk_mq_complete_request_direct() in order to complete the request.

Callers from process context can complete the request directly instead
waking ksoftirqd.

Link: https://lore.kernel.org/r/Yfw7JaszshmfYa1d@flow
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-02-07 23:14:15 -05:00
Christoph Hellwig
f3fa33acca block: remove the ->rq_disk field in struct request
Just use the disk attached to the request_queue instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211126121802.2090656-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29 06:41:29 -07:00
Linus Torvalds
6cbcc7ab21 SCSI misc on 20211112
This series is all the stragglers that didn't quite make the first
 merge window pull.  It's mostly minor updates and bug fixes of merge
 window code but it also has two driver updates: ufs and qla2xxx.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull more SCSI updates from James Bottomley:
 "This series is all the stragglers that didn't quite make the first
  merge window pull. It's mostly minor updates and bug fixes of merge
  window code but it also has two driver updates: ufs and qla2xxx"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (46 commits)
  scsi: scsi_debug: Don't call kcalloc() if size arg is zero
  scsi: core: Remove command size deduction from scsi_setup_scsi_cmnd()
  scsi: scsi_ioctl: Validate command size
  scsi: ufs: ufshpb: Properly handle max-single-cmd
  scsi: core: Avoid leaving shost->last_reset with stale value if EH does not run
  scsi: bsg: Fix errno when scsi_bsg_register_queue() fails
  scsi: sr: Remove duplicate assignment
  scsi: ufs: ufs-exynos: Introduce ExynosAuto v9 virtual host
  scsi: ufs: ufs-exynos: Multi-host configuration for ExynosAuto v9
  scsi: ufs: ufs-exynos: Support ExynosAuto v9 UFS
  scsi: ufs: ufs-exynos: Add pre/post_hce_enable drv callbacks
  scsi: ufs: ufs-exynos: Factor out priv data init
  scsi: ufs: ufs-exynos: Add EXYNOS_UFS_OPT_SKIP_CONFIG_PHY_ATTR option
  scsi: ufs: ufs-exynos: Support custom version of ufs_hba_variant_ops
  scsi: ufs: ufs-exynos: Add setup_clocks callback
  scsi: ufs: ufs-exynos: Add refclkout_stop control
  scsi: ufs: ufs-exynos: Simplify drv_data retrieval
  scsi: ufs: ufs-exynos: Change pclk available max value
  scsi: ufs: Add quirk to enable host controller without PH configuration
  scsi: ufs: Add quirk to handle broken UIC command
  ...
2021-11-12 12:25:50 -08:00
Linus Torvalds
fe91c4725a SCSI misc on 20211105
This series consists of the usual driver updates (ufs, smartpqi, lpfc,
 target, megaraid_sas, hisi_sas, qla2xxx) and minor updates and bug
 fixes.  Notable core changes are the removal of scsi->tag which caused
 some churn in obsolete drivers and a sweep through all drivers to call
 scsi_done() directly instead of scsi->done() which removes a pointer
 indirection from the hot path and a move to register core sysfs files
 earlier, which means they're available to KOBJ_ADD processing, which
 necessitates switching all drivers to using attribute groups.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This consists of the usual driver updates (ufs, smartpqi, lpfc,
  target, megaraid_sas, hisi_sas, qla2xxx) and minor updates and bug
  fixes.

  Notable core changes are the removal of scsi->tag which caused some
  churn in obsolete drivers and a sweep through all drivers to call
  scsi_done() directly instead of scsi->done() which removes a pointer
  indirection from the hot path and a move to register core sysfs files
  earlier, which means they're available to KOBJ_ADD processing, which
  necessitates switching all drivers to using attribute groups"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (279 commits)
  scsi: lpfc: Update lpfc version to 14.0.0.3
  scsi: lpfc: Allow fabric node recovery if recovery is in progress before devloss
  scsi: lpfc: Fix link down processing to address NULL pointer dereference
  scsi: lpfc: Allow PLOGI retry if previous PLOGI was aborted
  scsi: lpfc: Fix use-after-free in lpfc_unreg_rpi() routine
  scsi: lpfc: Correct sysfs reporting of loop support after SFP status change
  scsi: lpfc: Wait for successful restart of SLI3 adapter during host sg_reset
  scsi: lpfc: Revert LOG_TRACE_EVENT back to LOG_INIT prior to driver_resource_setup()
  scsi: ufs: ufshcd-pltfrm: Fix memory leak due to probe defer
  scsi: ufs: mediatek: Avoid sched_clock() misuse
  scsi: mpt3sas: Make mpt3sas_dev_attrs static
  scsi: scsi_transport_sas: Add 22.5 Gbps link rate definitions
  scsi: target: core: Stop using bdevname()
  scsi: aha1542: Use memcpy_{from,to}_bvec()
  scsi: sr: Add error handling support for add_disk()
  scsi: sd: Add error handling support for add_disk()
  scsi: target: Perform ALUA group changes in one step
  scsi: target: Replace lun_tg_pt_gp_lock with rcu in I/O path
  scsi: target: Fix alua_tg_pt_gps_count tracking
  scsi: target: Fix ordered tag handling
  ...
2021-11-05 08:42:02 -07:00
Ewan D. Milne
5ae17501bc scsi: core: Avoid leaving shost->last_reset with stale value if EH does not run
The changes to issue the abort from the scmd->abort_work instead of the EH
thread introduced a problem if eh_deadline is used.  If aborting the
command(s) is successful, and there are never any scmds added to the
shost->eh_cmd_q, there is no code path which will reset the ->last_reset
value back to zero.

The effect of this is that after a successful abort with no EH thread
activity, a subsequent timeout, perhaps a long time later, might
immediately be considered past a user-set eh_deadline time, and the host
will be reset with no attempt at recovery.

Fix this by resetting ->last_reset back to zero in scmd_eh_abort_handler()
if it is determined that the EH thread will not run to do this.

Thanks to Gopinath Marappan for investigating this problem.

Link: https://lore.kernel.org/r/20211029194311.17504-2-emilne@redhat.com
Fixes: e494f6a728 ("[SCSI] improved eh timeout handler")
Cc: stable@vger.kernel.org
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-11-03 21:33:50 -04:00
Christoph Hellwig
68ec3b819a scsi: add a scsi_alloc_request helper
Add a new helper that calls blk_get_request and initializes the
scsi_request to avoid the indirect call through ->.initialize_rq_fn.

Note that this makes the pktcdvd driver depend on the SCSI core, but
given that only SCSI devices support SCSI passthrough requests that
is not a functional change.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20211021060607.264371-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-22 08:33:57 -06:00
Bart Van Assche
11b68e36b1 scsi: core: Call scsi_done directly
Conditional statements are faster than indirect calls. Hence call
scsi_done() directly. Since this patch removes the last user of the
scsi_done member, also remove that data structure member.

Link: https://lore.kernel.org/r/20211007204618.2196847-11-bvanassche@acm.org
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-10-16 21:31:43 -04:00
Bart Van Assche
a710eacb9d scsi: core: Rename scsi_mq_done() into scsi_done() and export it
Since the removal of the legacy block layer there is only one completion
function left in the SCSI core, namely scsi_mq_done(). Rename it into
scsi_done(). Export that function to allow SCSI LLDs to call it directly.

Link: https://lore.kernel.org/r/20211007202923.2174984-3-bvanassche@acm.org
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-10-16 21:28:43 -04:00
Bart Van Assche
bf23e61903 scsi: core: Use a structure member to track the SCSI command submitter
Conditional statements are faster than indirect calls. Use a structure
member to track the SCSI command submitter such that later patches can call
scsi_done(scmd) instead of scmd->scsi_done(scmd).

The asymmetric behavior that scsi_send_eh_cmnd() sets the submission
context to the SCSI error handler and that it does not restore the
submission context to the SCSI core is retained.

Link: https://lore.kernel.org/r/20211007202923.2174984-2-bvanassche@acm.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-10-16 21:28:43 -04:00
Bart Van Assche
a7c0520669 scsi: core: Remove include <scsi/scsi_host.h> from scsi_cmnd.h
There are no dependencies in <scsi/scsi_cmnd.h> on the <scsi/scsi_host.h>
header file. Hence remove the scsi_host.h include directive from
scsi_cmnd.h. This include directive was introduced in February 2021 by
commit af1830956d ("scsi: core: Add mq_poll support to SCSI layer").

Link: https://lore.kernel.org/r/20210917212751.2676054-1-bvanassche@acm.org
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-09-21 23:54:44 -04:00
John Garry
4c7b6ea336 scsi: core: Remove scsi_cmnd.tag
It is never read, so get rid of it.

Link: https://lore.kernel.org/r/1628862553-179450-4-git-send-email-john.garry@huawei.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-17 22:28:39 -04:00
Martin K. Petersen
6a20e21ae1 scsi: core: Add helper to return number of logical blocks in a request
Link: https://lore.kernel.org/r/20210806040023.5355-2-martin.petersen@oracle.com
Cc: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:43 -04:00
Bart Van Assche
2266a2def9 scsi: core: Remove the request member from struct scsi_cmnd
Since all scsi_cmnd.request users are gone, remove the request pointer
from struct scsi_cmnd.

Link: https://lore.kernel.org/r/20210809230355.8186-53-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:42 -04:00
Bart Van Assche
aa8e25e500 scsi: core: Use scsi_cmd_to_rq() instead of scsi_cmnd.request
Prepare for removal of the request pointer by using scsi_cmd_to_rq()
instead. Cast away constness where necessary when passing a SCSI command
pointer to scsi_cmd_to_rq(). This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210809230355.8186-3-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:37 -04:00
Bart Van Assche
51f3a47889 scsi: core: Introduce the scsi_cmd_to_rq() function
The 'request' member of struct scsi_cmnd is superfluous. The struct request
and struct scsi_cmnd data structures are adjacent and hence the request
pointer can be derived easily from a scsi_cmnd pointer. Introduce a helper
function that performs that conversion in a type-safe way. This patch is
the first step towards removing the request member from struct
scsi_cmnd. Making that change has the following advantages:

 - This is a performance optimization since adding an offset to a pointer
   takes less time than dereferencing a pointer.

 - struct scsi_cmnd becomes smaller.

Link: https://lore.kernel.org/r/20210809230355.8186-2-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-11 22:25:36 -04:00
Martin K. Petersen
d2c945f01d scsi: core: Make scsi_get_lba() return the LBA
scsi_get_lba() confusingly returned the block layer sector number expressed
in units of 512 bytes. Now that we have a more aptly named
scsi_get_sector() function, make scsi_get_lba() return the actual LBA.

Link: https://lore.kernel.org/r/20210609033929.3815-13-martin.petersen@oracle.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-13-martin.petersen@oracle.com>
2021-07-20 22:10:42 -04:00
Bart Van Assche
f0f214fe8c scsi: core: Introduce scsi_get_sector()
Since scsi_get_lba() returns a sector_t value instead of the LBA, the name
of that function is confusing. Introduce an identical function
scsi_get_sector().

Link: https://lore.kernel.org/r/20210513223757.3938-2-bvanassche@acm.org
Link: https://lore.kernel.org/r/20210609033929.3815-11-martin.petersen@oracle.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-11-martin.petersen@oracle.com>
2021-07-20 22:10:42 -04:00
Martin K. Petersen
7ba46799d3 scsi: core: Add scsi_prot_ref_tag() helper
We are about to remove the request pointer from struct scsi_cmnd and that
will complicate getting to the ref_tag via t10_pi_ref_tag() in the various
drivers. Introduce a helper function to retrieve the reference tag so
drivers will not have to worry about the details.

Link: https://lore.kernel.org/r/20210609033929.3815-2-martin.petersen@oracle.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-2-martin.petersen@oracle.com>
2021-07-20 22:08:55 -04:00
Hannes Reinecke
54cf31d07a scsi: core: Drop message byte helper
The message byte is now unused, so we can drop the helper to set the
message byte and the check for message bytes during error recovery.

Link: https://lore.kernel.org/r/20210427083046.31620-38-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-05-31 22:48:24 -04:00
Hannes Reinecke
735b830c61 scsi: core: Add scsi_msg_to_host_byte()
Add helper to convert message byte into a host byte code.

Link: https://lore.kernel.org/r/20210427083046.31620-18-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-05-31 22:48:22 -04:00
Hannes Reinecke
f6b5a69706 scsi: core: Add get_{status,host}_byte() accessor functions
Add accessor functions for the host and status byte.

Link: https://lore.kernel.org/r/20210427083046.31620-17-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-05-31 22:48:22 -04:00
Hannes Reinecke
54c2908619 scsi: core: Drop the now obsolete driver_byte definitions
The driver_byte field in the result is now unused, so we can drop the
definitions.

Link: https://lore.kernel.org/r/20210427083046.31620-15-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-05-31 22:48:22 -04:00
Hannes Reinecke
f2b1e9c6f8 scsi: core: Introduce scsi_build_sense()
Introduce scsi_build_sense() as a wrapper around scsi_build_sense_buffer()
to format the buffer and set the correct SCSI status.

Link: https://lore.kernel.org/r/20210427083046.31620-8-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-05-31 22:48:21 -04:00
Linus Torvalds
d72cd4ad41 SCSI misc on 20210428
This series consists of the usual driver updates (ufs, target, tcmu,
 smartpqi, lpfc, zfcp, qla2xxx, mpt3sas, pm80xx).  The major core
 change is using a sbitmap instead of an atomic for queue tracking.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This consists of the usual driver updates (ufs, target, tcmu,
  smartpqi, lpfc, zfcp, qla2xxx, mpt3sas, pm80xx).

  The major core change is using a sbitmap instead of an atomic for
  queue tracking"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (412 commits)
  scsi: target: tcm_fc: Fix a kernel-doc header
  scsi: target: Shorten ALUA error messages
  scsi: target: Fix two format specifiers
  scsi: target: Compare explicitly with SAM_STAT_GOOD
  scsi: sd: Introduce a new local variable in sd_check_events()
  scsi: dc395x: Open-code status_byte(u8) calls
  scsi: 53c700: Open-code status_byte(u8) calls
  scsi: smartpqi: Remove unused functions
  scsi: qla4xxx: Remove an unused function
  scsi: myrs: Remove unused functions
  scsi: myrb: Remove unused functions
  scsi: mpt3sas: Fix two kernel-doc headers
  scsi: fcoe: Suppress a compiler warning
  scsi: libfc: Fix a format specifier
  scsi: aacraid: Remove an unused function
  scsi: core: Introduce enum scsi_disposition
  scsi: core: Modify the scsi_send_eh_cmnd() return value for the SDEV_BLOCK case
  scsi: core: Rename scsi_softirq_done() into scsi_complete()
  scsi: core: Remove an incorrect comment
  scsi: core: Make the scsi_alloc_sgtables() documentation more accurate
  ...
2021-04-28 17:22:10 -07:00
Christoph Hellwig
aaff5ebaa2 scsi: remove the unchecked_isa_dma flag
Remove the unchecked_isa_dma now that all users are gone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20210331073001.46776-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06 09:28:17 -06:00
Kashyap Desai
af1830956d scsi: core: Add mq_poll support to SCSI layer
Currently IOPOLL support is only available in block layer. This patch
adds mq_poll support to the SCSI layer.

Link: https://lore.kernel.org/r/20210215074048.19424-2-kashyap.desai@broadcom.com
Cc: sumit.saxena@broadcom.com
Cc: chandrakanth.patil@broadcom.com
Cc: linux-block@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 17:37:03 -05:00
Ming Lei
d022d18c04 scsi: blk-mq: Add callbacks for storing & retrieving budget token
Since SCSI is the only driver which requires dispatch budget move the token
from struct request to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20210122023317.687987-8-ming.lei@redhat.com
Cc: Omar Sandoval <osandov@fb.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com>
Cc: Ewan D. Milne <emilne@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Tested-by: Sumanesh Samanta <sumanesh.samanta@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 17:36:59 -05:00
Hannes Reinecke
d37932a916 scsi: core: Add 'set_status_byte()' accessor
Add the missing 'set_status_byte()' accessor function.

Link: https://lore.kernel.org/r/20210113090500.129644-28-hare@suse.de
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-01-22 21:14:11 -05:00
Christoph Hellwig
7007e9dd56 scsi: core: Clean up allocation and freeing of sgtables
Rename scsi_init_io() to scsi_alloc_sgtables(), and ensure callers call
scsi_free_sgtables() to cleanup failures close to scsi_init_io() instead of
leaking it down the generic I/O submission path.

Link: https://lore.kernel.org/r/20201005084130.143273-9-hch@lst.de
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-10-07 21:48:27 -04:00
Linus Torvalds
818dbde78e SCSI misc on 20200605
This series consists of the usual driver updates (qla2xxx, ufs, zfcp,
 target, scsi_debug, lpfc, qedi, qedf, hisi_sas, mpt3sas) plus a host
 of other minor updates.  There are no major core changes in this
 series apart from a refactoring in scsi_lib.c.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 :This series consists of the usual driver updates (qla2xxx, ufs, zfcp,
  target, scsi_debug, lpfc, qedi, qedf, hisi_sas, mpt3sas) plus a host
  of other minor updates.

  There are no major core changes in this series apart from a
  refactoring in scsi_lib.c"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (207 commits)
  scsi: ufs: ti-j721e-ufs: Fix unwinding of pm_runtime changes
  scsi: cxgb3i: Fix some leaks in init_act_open()
  scsi: ibmvscsi: Make some functions static
  scsi: iscsi: Fix deadlock on recovery path during GFP_IO reclaim
  scsi: ufs: Fix WriteBooster flush during runtime suspend
  scsi: ufs: Fix index of attributes query for WriteBooster feature
  scsi: ufs: Allow WriteBooster on UFS 2.2 devices
  scsi: ufs: Remove unnecessary memset for dev_info
  scsi: ufs-qcom: Fix scheduling while atomic issue
  scsi: mpt3sas: Fix reply queue count in non RDPQ mode
  scsi: lpfc: Fix lpfc_nodelist leak when processing unsolicited event
  scsi: target: tcmu: Fix a use after free in tcmu_check_expired_queue_cmd()
  scsi: vhost: Notify TCM about the maximum sg entries supported per command
  scsi: qla2xxx: Remove return value from qla_nvme_ls()
  scsi: qla2xxx: Remove an unused function
  scsi: iscsi: Register sysfs for iscsi workqueue
  scsi: scsi_debug: Parser tables and code interaction
  scsi: core: Refactor scsi_mq_setup_tags function
  scsi: core: Fix incorrect usage of shost_for_each_device
  scsi: qla2xxx: Fix endianness annotations in source files
  ...
2020-06-05 15:11:50 -07:00
Hannes Reinecke
646d4b5076 scsi: core: Remove 'list' entry from struct scsi_cmnd
Leftover from cmd_list removal.

Link: https://lore.kernel.org/r/20200507062642.100612-1-hare@suse.de
Fixes: c5a9707672 ("scsi: core: Remove cmd_list functionality")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 21:06:20 -04:00
Christoph Hellwig
bdf8710d69 block: move dma_pad handling from blk_rq_map_sg into the callers
There are only two callers of blk_rq_map_sg/__blk_rq_map_sg that set
the dma_pad value in the queue.  Move the handling into those callers
instead of burdening the common code, and move the ->extra_len field
from struct request to struct scsi_cmnd.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-22 10:47:39 -06:00
Hannes Reinecke
c5a9707672 scsi: core: Remove cmd_list functionality
Remove cmd_list functionality; no users left.  With that the
scsi_put_command() becomes empty, so remove that one, too.

Link: https://lore.kernel.org/r/20200228075318.91255-14-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart van Assche <bvanassche@acm.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-02-28 20:54:55 -05:00
Damien Le Moal
9237f04e12 scsi: core: Fix scsi_get/set_resid() interface
struct scsi_cmnd cmd->req.resid_len which is returned and set respectively
by the helper functions scsi_get_resid() and scsi_set_resid() is an
unsigned int. Reflect this fact in the interface of these helper functions.

Also fix compilation errors due to min() and max() type mismatch introduced
by this change in scsi debug code, usb transport code and in the USB ENE
card reader driver.

Link: https://lore.kernel.org/r/20191030090847.25650-1-damien.lemoal@wdc.com
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-11-08 21:34:49 -05:00
Ming Lei
6eb045e092 scsi: core: avoid host-wide host_busy counter for scsi_mq
It isn't necessary to check the host depth in scsi_queue_rq() any more
since it has been respected by blk-mq before calling scsi_queue_rq() via
getting driver tag.

Lots of LUNs may attach to same host and per-host IOPS may reach millions,
so we should avoid expensive atomic operations on the host-wide counter in
the IO path.

This patch implements scsi_host_busy() via blk_mq_tagset_busy_iter() with
one scsi command state for reading the count of busy IOs for scsi_mq.

It is observed that IOPS is increased by 15% in IO test on scsi_debug (32
LUNs, 32 submit queues, 1024 can_queue, libaio/dio) in a dual-socket
system.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ewan D. Milne <emilne@redhat.com>
Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20191025065855.6309-1-ming.lei@redhat.com
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-11-01 20:12:50 -04:00
Paolo Bonzini
8930a6c207 scsi: core: add support for request batching
This allows a list of requests to be issued, with the LLD only writing the
hardware doorbell when necessary, after the last request was prepared.
This is more efficient if we have lists of requests to issue, particularly
on virtualized hardware, where writing the doorbell is more expensive than
on real hardware.

The use case for this is plugged IO, where blk-mq flushes a batch of
requests all at once.

The API is the same as for blk-mq, just with blk-mq concepts tweaked to
fit the SCSI subsystem API: the "last" flag in blk_mq_queue_data becomes a
flag in scsi_cmnd, while the queue_num in the commit_rqs callback is
extracted from the hctx and passed as a parameter.

The only complication is that blk-mq uses different plugging heuristics
depending on whether commit_rqs is present or not.  So we have two
different sets of blk_mq_ops and pick one depending on whether the
scsi_host template uses commit_rqs or not.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-07-22 16:44:07 -04:00