kernel/linux.git/drivers/scsi/sd.h, branch v7.0.10

block: introduce disk_report_zone()

2025-11-05T15:07:21+00:00

Commit b76b840fd933 ("dm: Fix dm-zoned-reclaim zone write pointer alignment") introduced an indirect call for the callback function of a report zones executed with blkdev_report_zones(). This is necessary so that the function disk_zone_wplug_sync_wp_offset() can be called to refresh a zone write plug zone write pointer offset after a write error. However, this solution makes following the path of a zone information harder to understand. Clean this up by introducing the new blk_report_zones_args structure to define a zone report callback and its private data and introduce the helper function disk_report_zone() which calls both disk_zone_wplug_sync_wp_offset() and the zone report user callback function for all zones of a zone report. This helper function must be called by all block device drivers that implement the report zones block operation in order to correctly report a zone information. All block device drivers supporting the report_zones block operation are updated to use this new scheme. Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Chaitanya Kulkarni Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe

scsi: sd: Atomic write support

2024-06-20T21:19:17+00:00

Support is divided into two main areas: - reading VPD pages and setting sdev request_queue limits - support WRITE ATOMIC (16) command and tracing The relevant block limits VPD page need to be read to allow the block layer request_queue atomic write limits to be set. These VPD page limits are described in sbc4r22 section 6.6.4 - Block limits VPD page. There are five limits of interest: - MAXIMUM ATOMIC TRANSFER LENGTH - ATOMIC ALIGNMENT - ATOMIC TRANSFER LENGTH GRANULARITY - MAXIMUM ATOMIC TRANSFER LENGTH WITH BOUNDARY - MAXIMUM ATOMIC BOUNDARY SIZE MAXIMUM ATOMIC TRANSFER LENGTH is the maximum length for a WRITE ATOMIC (16) command. It will not be greater than the device MAXIMUM TRANSFER LENGTH. ATOMIC ALIGNMENT and ATOMIC TRANSFER LENGTH GRANULARITY are the minimum alignment and length values for an atomic write in terms of logical blocks. Unlike NVMe, SCSI does not specify an LBA space boundary, but does specify a per-IO boundary granularity. The maximum boundary size is specified in MAXIMUM ATOMIC BOUNDARY SIZE. When used, this boundary value is set in the WRITE ATOMIC (16) ATOMIC BOUNDARY field - layout for the WRITE_ATOMIC_16 command can be found in sbc4r22 section 5.48. This boundary value is the granularity size at which the device may atomically write the data. A value of zero in WRITE ATOMIC (16) ATOMIC BOUNDARY field means that all data must be atomically written together. MAXIMUM ATOMIC TRANSFER LENGTH WITH BOUNDARY is the maximum atomic write length if a non-zero boundary value is set. For atomic write support, the WRITE ATOMIC (16) boundary is not of much interest, as the block layer expects each request submitted to be executed atomically. However, the SCSI spec does leave itself open to a quirky scenario where MAXIMUM ATOMIC TRANSFER LENGTH is zero, yet MAXIMUM ATOMIC TRANSFER LENGTH WITH BOUNDARY and MAXIMUM ATOMIC BOUNDARY SIZE are both non-zero. This case will be supported. To set the block layer request_queue atomic write capabilities, sanitize the VPD page limits and set limits as follows: - atomic_write_unit_min is derived from granularity and alignment values. If no granularity value is not set, use physical block size - atomic_write_unit_max is derived from MAXIMUM ATOMIC TRANSFER LENGTH. In the scenario where MAXIMUM ATOMIC TRANSFER LENGTH is zero and boundary limits are non-zero, use MAXIMUM ATOMIC BOUNDARY SIZE for atomic_write_unit_max. New flag scsi_disk.use_atomic_write_boundary is set for this scenario. - atomic_write_boundary_bytes is set to zero always SCSI also supports a WRITE ATOMIC (32) command, which is for type 2 protection enabled. This is not going to be supported now, so check for T10_PI_TYPE2_PROTECTION when setting any request_queue limits. To handle an atomic write request, add support for WRITE ATOMIC (16) command in handler sd_setup_atomic_cmnd(). Flag use_atomic_write_boundary is checked here for encoding ATOMIC BOUNDARY field. Trace info is also added for WRITE_ATOMIC_16 command. Reviewed-by: Martin K. Petersen Signed-off-by: John Garry Acked-by: Darrick J. Wong Reviewed-by: Darrick J. Wong Link: https://lore.kernel.org/r/20240620125359.2684798-9-john.g.garry@oracle.com Signed-off-by: Jens Axboe

sd: remove sd_is_zoned

2024-06-19T13:58:27+00:00

Since commit 7437bb73f087 ("block: remove support for the host aware zone model"), only ZBC devices expose a zoned access model. sd_is_zoned is used to check for that and thus return false for host aware devices. Replace the helper with the simple open coded TYPE_ZBC check to fix this. Fixes: 7437bb73f087 ("block: remove support for the host aware zone model") Signed-off-by: Christoph Hellwig Reviewed-by: Bart Van Assche Reviewed-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20240617060532.127975-3-hch@lst.de Signed-off-by: Jens Axboe

block: move integrity information into queue_limits

2024-06-14T16:20:07+00:00

Move the integrity information into the queue limits so that it can be set atomically with other queue limits, and that the sysfs changes to the read_verify and write_generate flags are properly synchronized. This also allows to provide a more useful helper to stack the integrity fields, although it still is separate from the main stacking function as not all stackable devices want to inherit the integrity settings. Even with that it greatly simplifies the code in md and dm. Note that the integrity field is moved as-is into the queue limits. While there are good arguments for removing the separate blk_integrity structure, this would cause a lot of churn and might better be done at a later time if desired. However the integrity field in the queue_limits structure is now unconditional so that various ifdefs can be avoided or replaced with IS_ENABLED(). Given that tiny size of it that seems like a worthwhile trade off. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de Signed-off-by: Jens Axboe

sd: convert to the atomic queue limits API

2024-06-14T16:19:44+00:00

Assign all queue limits through a local queue_limits variable and queue_limits_commit_update so that we can't race updating them from multiple places, and freeze the queue when updating them so that in-progress I/O submissions don't see half-updated limits. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: John Garry Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240531074837.1648501-12-hch@lst.de Signed-off-by: Jens Axboe

scsi: sd: Use the block layer zone append emulation

2024-04-17T14:44:03+00:00

Set the request queue of a TYPE_ZBC device as needing zone append emulation by setting the device queue max_zone_append_sectors limit to 0. This enables the block layer generic implementation provided by zone write plugging. With this, the sd driver will never see a REQ_OP_ZONE_APPEND request and the zone append emulation code implemented in sd_zbc.c can be removed. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Tested-by: Hans Holmberg Tested-by: Dennis Maisenbacher Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240408014128.205141-14-dlemoal@kernel.org Signed-off-by: Jens Axboe

scsi: sd: Translate data lifetime information

2024-02-27T02:37:26+00:00

Recently T10 standardized SBC constrained streams. This mechanism allows to pass data lifetime information to SCSI devices in the group number field. Add support for translating write hint information into a permanent stream number in the sd driver. Use WRITE(10) instead of WRITE(6) if data lifetime information is present because the WRITE(6) command does not have a GROUP NUMBER field. Cc: Martin K. Petersen Cc: Christoph Hellwig Cc: Damien Le Moal Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240130214911.1863909-12-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: core: Query the Block Limits Extension VPD page

2024-02-27T02:37:26+00:00

Parse the Reduced Stream Control Supported (RSCS) bit from the block limits extension VPD page. The RSCS bit is defined in SBC-5 r05 (https://www.t10.org/cgi-bin/ac.pl?t=f&f=sbc5r05.pdf). Reviewed-by: Avri Altman Reviewed-by: Daejun Park Cc: Martin K. Petersen Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240130214911.1863909-10-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: sd: Do not issue commands to suspended disks on shutdown

2023-09-28T12:23:18+00:00

If an error occurs when resuming a host adapter before the devices attached to the adapter are resumed, the adapter low level driver may remove the scsi host, resulting in a call to sd_remove() for the disks of the host. This in turn results in a call to sd_shutdown() which will issue a synchronize cache command and a start stop unit command to spindown the disk. sd_shutdown() issues the commands only if the device is not already runtime suspended but does not check the power state for system-wide suspend/resume. That is, the commands may be issued with the device in a suspended state, which causes PM resume to hang, forcing a reset of the machine to recover. Fix this by tracking the suspended state of a disk by introducing the suspended boolean field in the scsi_disk structure. This flag is set to true when the disk is suspended is sd_suspend_common() and resumed with sd_resume(). When suspended is true, sd_shutdown() is not executed from sd_remove(). Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Bart Van Assche Reviewed-by: Martin K. Petersen

scsi: sd: Revert "Rework asynchronous resume support"

2022-08-23T02:45:25+00:00

Although commit 88f1669019bd ("scsi: sd: Rework asynchronous resume support") eliminates a delay for some ATA disks after resume, it causes resume of ATA disks to fail on other setups. See also: * "Resume process hangs for 5-6 seconds starting sometime in 5.16" (https://bugzilla.kernel.org/show_bug.cgi?id=215880). * Geert's regression report (https://lore.kernel.org/linux-scsi/alpine.DEB.2.22.394.2207191125130.1006766@ramsan.of.borg/). This is what I understand about this issue: * During resume, ata_port_pm_resume() starts the SCSI error handler. This changes the SCSI host state into SHOST_RECOVERY and causes scsi_queue_rq() to return BLK_STS_RESOURCE. * sd_resume() calls sd_start_stop_device() for ATA devices. That function in turn calls sd_submit_start() which tries to submit a START STOP UNIT command. That command can only be submitted after the SCSI error handler has changed the SCSI host state back to SHOST_RUNNING. * The SCSI error handler runs on its own thread and calls schedule_work(&(ap->scsi_rescan_task)). That causes ata_scsi_dev_rescan() to be called from the context of a kernel workqueue. That call hangs in blk_mq_get_tag(). I'm not sure why - maybe because all available tags have been allocated by sd_submit_start() calls (this is a guess). Link: https://lore.kernel.org/r/20220816172638.538734-1-bvanassche@acm.org Fixes: 88f1669019bd ("scsi: sd: Rework asynchronous resume support") Cc: Damien Le Moal Cc: Hannes Reinecke Cc: Geert Uytterhoeven Cc: gzhqyz@gmail.com Reported-by: Geert Uytterhoeven Reported-by: gzhqyz@gmail.com Reported-and-tested-by: Vlastimil Babka Tested-by: John Garry Tested-by: Hans de Goede Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen