scsi: sd: Remove LBPRZ dependency for discards
Separating discards and zeroout operations allows us to remove the LBPRZ
block zeroing constraints from discards and honor the device preferences
for UNMAP commands.
If supported by the device, we'll also choose UNMAP over one of the
WRITE SAME variants for discards.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index acf9d17..8cf34a8 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -685,24 +685,11 @@
unsigned int logical_block_size = sdkp->device->sector_size;
unsigned int max_blocks = 0;
- /*
- * When LBPRZ is reported, discard alignment and granularity
- * must be fixed to the logical block size. Otherwise the block
- * layer will drop misaligned portions of the request which can
- * lead to data corruption. If LBPRZ is not set, we honor the
- * device preference.
- */
- if (sdkp->lbprz) {
- q->limits.discard_alignment = 0;
- q->limits.discard_granularity = logical_block_size;
- } else {
- q->limits.discard_alignment = sdkp->unmap_alignment *
- logical_block_size;
- q->limits.discard_granularity =
- max(sdkp->physical_block_size,
- sdkp->unmap_granularity * logical_block_size);
- }
-
+ q->limits.discard_alignment =
+ sdkp->unmap_alignment * logical_block_size;
+ q->limits.discard_granularity =
+ max(sdkp->physical_block_size,
+ sdkp->unmap_granularity * logical_block_size);
sdkp->provisioning_mode = mode;
switch (mode) {
@@ -2842,7 +2829,7 @@
sd_config_discard(sdkp, SD_LBP_WS16);
} else { /* LBP VPD page tells us what to use */
- if (sdkp->lbpu && sdkp->max_unmap_blocks && !sdkp->lbprz)
+ if (sdkp->lbpu && sdkp->max_unmap_blocks)
sd_config_discard(sdkp, SD_LBP_UNMAP);
else if (sdkp->lbpws)
sd_config_discard(sdkp, SD_LBP_WS16);