Single LUN multi-actuator hard-disks are cappable to seek and execute multiple commands in parallel. This capability is exposed to the host using the Concurrent Positioning Ranges VPD page (SCSI) and Log (ATA). Each positioning range describes the contiguous set of LBAs that an actuator serves. This series adds support the scsi disk driver to retreive this information and advertize it to user space through sysfs. libata is also modified to handle ATA drives. The first patch adds the block layer plumbing to expose concurrent sector ranges of the device through sysfs as a sub-directory of the device sysfs queue directory. Patch 2 and 3 add support to sd and libata. Finally patch 4 documents the sysfs queue attributed changes. This series does not attempt in any way to optimize accesses to multi-actuator devices (e.g. block IO scheduler or filesystems). This initial support only exposes the actuators information to user space through sysfs. Changes from v2: * Update patch 1 to fix a compilation warning for a potential NULL pointer dereference of the cr argument of blk_queue_set_cranges(). Warning reported by the kernel test robot <lkp@xxxxxxxxx>). Changes from v1: * Moved libata-scsi hunk from patch 1 to patch 3 where it belongs * Fixed unintialized variable in patch 2 Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx * Changed patch 3 adding struct ata_cpr_log to contain both the number of concurrent ranges and the array of concurrent ranges. * Added a note in the documentation (patch 4) about the unit used for the concurrent ranges attributes. Damien Le Moal (4): block: Add concurrent positioning ranges support scsi: sd: add concurrent positioning ranges support libata: support concurrent positioning ranges log doc: document sysfs queue/cranges attributes Documentation/block/queue-sysfs.rst | 30 ++- block/Makefile | 2 +- block/blk-cranges.c | 295 ++++++++++++++++++++++++++++ block/blk-sysfs.c | 13 ++ block/blk.h | 3 + drivers/ata/libata-core.c | 52 +++++ drivers/ata/libata-scsi.c | 48 ++++- drivers/scsi/sd.c | 81 ++++++++ drivers/scsi/sd.h | 1 + include/linux/ata.h | 1 + include/linux/blkdev.h | 29 +++ include/linux/libata.h | 15 ++ 12 files changed, 559 insertions(+), 11 deletions(-) create mode 100644 block/blk-cranges.c -- 2.31.1
