On 13-04-16 09:11 AM, Akinobu Mita wrote:
I tried testing the logical block provisioning support in scsi_debug,
but it didn't work as I expected.
For example, load scsi_debug module with UNMAP command supported
and fill the storage with random data.
# modprobe scsi_debug lbpu=1
# dd if=/dev/urandom of=/dev/sdb
Then, try to unmap LBA 0, but Get LBA status reports:
# sg_unmap --lba=0 --num=1 /dev/sdb
# sg_get_lba_status --lba=0 /dev/sdb
descriptor LBA: 0x0000000000000000 blocks: 16384 mapped
This is unexpected result. Because UNMAP command to LBA 0 finished
without any errors, but Get LBA status shows that LBA 0 is still mapped.
I looked around the logical block provisioning support in scsi_debug,
and I found several problems there. This patch series tries to fix
these problems and it is broken into small patches as much as possible
for ease of review.
Cc: "James E.J. Bottomley" <JBottomley@xxxxxxxxxxxxx>
Cc: linux-scsi@xxxxxxxxxxxxxxx
Cc: Douglas Gilbert <dgilbert@xxxxxxxxxxxx>
Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Akinobu Mita (6):
scsi_debug: call map_region() and unmap_region() only when needed
scsi_debug: prohibit scsi_debug_unmap_granularity ==
scsi_debug_unmap_alignment
scsi_debug: clear correct memory region when LBPRZ is enabled
scsi_debug: add translation functions between LBA and index of
provisioning map
scsi_debug: fix initialization of provisioning map
scsi_debug: fix logical block provisioning support
I'd like to see some feedback from Martin Petersen on this
set of patches. For my part, for this patch series (1/6
fo 6/6):
Acked-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
