Export max open zones and max active zones to sysfs. This patch series depends on the Zoned Namespace Command Set series: https://lore.kernel.org/linux-nvme/20200615233424.13458-1-keith.busch@xxxxxxx/ All zoned block devices in the kernel utilize the "zoned block device support" (CONFIG_BLK_DEV_ZONED). The Zoned Namespace Command Set Specification defines two different resource limits: Max Open Resources and Max Active Resources. The ZAC and ZBC standards define a MAXIMUM NUMBER OF OPEN SEQUENTIAL WRITE REQUIRED ZONES field. Since the ZNS Max Open Resources field has the same purpose as the ZAC/ZBC field, (the ZNS field is 0's based, the ZAC/ZBC field isn't), create a common "max_open_zones" definition in the sysfs documentation, and export both the ZNS field and the ZAC/ZBC field according to this new common definition. The ZNS Max Active Resources field does not have an equivalent field in ZAC/ZBC, however, since both ZAC/ZBC and ZNS utilize the "zoned block device support" in the kernel, create a "max_active_zones" definition in the sysfs documentation, similar to "max_open_zones", and export it according to this new definition. For ZAC/ZBC devices, this field will be exported as 0, meaning "no limit". Niklas Cassel (2): block: add max_open_zones to blk-sysfs block: add max_active_zones to blk-sysfs Documentation/block/queue-sysfs.rst | 14 ++++++++++ block/blk-sysfs.c | 27 +++++++++++++++++++ drivers/nvme/host/zns.c | 2 ++ drivers/scsi/sd_zbc.c | 5 ++++ include/linux/blkdev.h | 40 +++++++++++++++++++++++++++++ 5 files changed, 88 insertions(+) -- 2.26.2
