sd: Fix maximum I/O size for BLOCK_PC requests
Commit bcdb247c6b6a ("sd: Limit transfer length") clamped the maximum
size of an I/O request to the MAXIMUM TRANSFER LENGTH field in the BLOCK
LIMITS VPD. This had the unfortunate effect of also limiting the maximum
size of non-filesystem requests sent to the device through sg/bsg.
Avoid using blk_queue_max_hw_sectors() and set the max_sectors queue
limit directly.
Also update the comment in blk_limits_max_hw_sectors() to clarify that
max_hw_sectors defines the limit for the I/O controller only.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Brian King <brking@linux.vnet.ibm.com>
Tested-by: Brian King <brking@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: James Bottomley <JBottomley@Odin.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 3b2fcb4..a20da8c 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2770,9 +2770,9 @@
max_xfer = sdkp->max_xfer_blocks;
max_xfer <<= ilog2(sdp->sector_size) - 9;
- max_xfer = min_not_zero(queue_max_hw_sectors(sdkp->disk->queue),
- max_xfer);
- blk_queue_max_hw_sectors(sdkp->disk->queue, max_xfer);
+ sdkp->disk->queue->limits.max_sectors =
+ min_not_zero(queue_max_hw_sectors(sdkp->disk->queue), max_xfer);
+
set_capacity(disk, sdkp->capacity);
sd_config_write_same(sdkp);
kfree(buffer);