From 6b7e9cde49691e04314342b7dce90c67ad567fcc Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Thu, 12 May 2016 22:17:34 -0400 Subject: [PATCH] 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: d0eb20a863ba ("sd: Optimal I/O size is in bytes, not sectors") Cc: stable@vger.kernel.org # 4.4+ Reported-by: Fam Zheng Reviewed-by: Bart Van Assche Reviewed-by: Christoph Hellwig Tested-by: Andrew Patterson Signed-off-by: Martin K. Petersen --- drivers/scsi/sd.c | 8 ++++---- drivers/scsi/sd.h | 5 +++++ 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index f459dff30512..60bff78e9ead 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -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; - else + 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 rw_max = BLK_DEF_MAX_SECTORS; /* Combine with controller limits */ diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 654630bb7d0e..765a6f1ac1b7 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -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: -- 2.20.1