[SCSI] scsi_debug: fix logical block provisioning support when unmap_alignment != 0
Commit b90ebc3d5c41c9164ae04efd2e4f8204c2a186f1 ("[SCSI] scsi_debug:
fix logical block provisioning support") fixed several issues with
logical block provisioning support, but it still doesn't properly fix
the cases when unmap_alignment > 0.
For example, load scsi_debug module with the following module parameters
and make all blocks mapped by filling the storage with zero.
# modprobe scsi_debug lbpu=1 unmap_alignment=1 unmap_granularity=4
# dd if=/dev/zero of=$DEV
Then, try to unmap the first unmappable blocks at lba=1, but GET LBA STATUS
unexpectedly reports that the last UNMAP has done nothing.
# sg_unmap --lba=1 --num=4 $DEV
# sg_get_lba_status --lba=1 $DEV
descriptor LBA: 0x0000000000000001 blocks: 16383 mapped
The problem is in map_index_to_lba(), which should return the first
LBA which is corresponding to a given index of provisioning map
(map_storep).
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 2f39b13..01c0ffa 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1997,8 +1997,14 @@
static sector_t map_index_to_lba(unsigned long index)
{
- return index * scsi_debug_unmap_granularity -
- scsi_debug_unmap_alignment;
+ sector_t lba = index * scsi_debug_unmap_granularity;
+
+ if (scsi_debug_unmap_alignment) {
+ lba -= scsi_debug_unmap_granularity -
+ scsi_debug_unmap_alignment;
+ }
+
+ return lba;
}
static unsigned int map_state(sector_t lba, unsigned int *num)