Commit 6b7e9cde authored by Martin K. Petersen's avatar Martin K. Petersen

sd: Fix rw_max for devices that report an optimal xfer size

For historic reasons, io_opt is in bytes and max_sectors in block layer
sectors. This interface inconsistency is error prone and should be
fixed. But for 4.4--4.7 let's make the unit difference explicit via a
wrapper function.

Fixes: d0eb20a8 ("sd: Optimal I/O size is in bytes, not sectors")
Cc: [email protected] # 4.4+
Reported-by: default avatarFam Zheng <[email protected]>
Reviewed-by: default avatarBart Van Assche <[email protected]>
Reviewed-by: default avatarChristoph Hellwig <[email protected]>
Tested-by: default avatarAndrew Patterson <[email protected]>
Signed-off-by: Martin K. Petersen's avatarMartin K. Petersen <[email protected]>
parent fbd83006
......@@ -2867,10 +2867,10 @@ static int sd_revalidate_disk(struct gendisk *disk)
if (sdkp->opt_xfer_blocks &&
sdkp->opt_xfer_blocks <= dev_max &&
sdkp->opt_xfer_blocks <= SD_DEF_XFER_BLOCKS &&
sdkp->opt_xfer_blocks * sdp->sector_size >= PAGE_SIZE)
rw_max = q->limits.io_opt =
sdkp->opt_xfer_blocks * sdp->sector_size;
logical_to_bytes(sdp, sdkp->opt_xfer_blocks) >= PAGE_SIZE) {
q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks);
rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
} else
/* Combine with controller limits */
......@@ -151,6 +151,11 @@ static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blo
return blocks << (ilog2(sdev->sector_size) - 9);
static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
return blocks * sdev->sector_size;
* A DIF-capable target device can be formatted with different
* protection schemes. Currently 0 through 3 are defined:
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