sd: Implement support for ZBC devices
Implement ZBC support functions to setup zoned disks, both
host-managed and host-aware models. Only zoned disks that satisfy
the following conditions are supported:
1) All zones are the same size, with the exception of an eventual
last smaller runt zone.
2) For host-managed disks, reads are unrestricted (reads are not
failed due to zone or write pointer alignement constraints).
Zoned disks that do not satisfy these 2 conditions are setup with
a capacity of 0 to prevent their use.
The function sd_zbc_read_zones, called from sd_revalidate_disk,
checks that the device satisfies the above two constraints. This
function may also change the disk capacity previously set by
sd_read_capacity for devices reporting only the capacity of
conventional zones at the beginning of the LBA range (i.e. devices
reporting rc_basis set to 0).
The capacity message output was moved out of sd_read_capacity into
a new function sd_print_capacity to include this eventual capacity
change by sd_zbc_read_zones. This new function also includes a call
to sd_zbc_print_zones to display the number of zones and zone size
of the device.
Signed-off-by: Hannes Reinecke <hare@suse.de>
[Damien: * Removed zone cache support
* Removed mapping of discard to reset write pointer command
* Modified sd_zbc_read_zones to include checks that the
device satisfies the kernel constraints
* Implemeted REPORT ZONES setup and post-processing based
on code from Shaun Tancheff <shaun.tancheff@seagate.com>
* Removed confusing use of 512B sector units in functions
interface]
Signed-off-by: Damien Le Moal <damien.lemoal@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Tested-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 38d938d..1520596 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -173,6 +173,7 @@
sd_mod-objs := sd.o
sd_mod-$(CONFIG_BLK_DEV_INTEGRITY) += sd_dif.o
+sd_mod-$(CONFIG_BLK_DEV_ZONED) += sd_zbc.o
sr_mod-objs := sr.o sr_ioctl.o sr_vendor.o
ncr53c8xx-flags-$(CONFIG_SCSI_ZALON) \