sd: Fix excessive capacity printing on devices with blocks bigger than 512 bytes

During revalidate we check whether device capacity has changed before we
decide whether to output disk information or not.

The check for old capacity failed to take into account that we scaled
sdkp->capacity based on the reported logical block size. And therefore
the capacity test would always fail for devices with sectors bigger than
512 bytes and we would print several copies of the same discovery
information.

Avoid scaling sdkp->capacity and instead adjust the value on the fly
when setting the block device capacity and generating fake C/H/S
geometry.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: <stable@vger.kernel.org>
Reported-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 8 insertions, 20 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 5a5457ac9cdb..8401697ff6aa 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1275,18 +1275,19 @@ static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
 	struct scsi_device *sdp = sdkp->device;
 	struct Scsi_Host *host = sdp->host;
+	sector_t capacity = logical_to_sectors(sdp, sdkp->capacity);
 	int diskinfo[4];
 
 	/* default to most commonly used values */
-        diskinfo[0] = 0x40;	/* 1 << 6 */
-       	diskinfo[1] = 0x20;	/* 1 << 5 */
-       	diskinfo[2] = sdkp->capacity >> 11;
-	
+	diskinfo[0] = 0x40;	/* 1 << 6 */
+	diskinfo[1] = 0x20;	/* 1 << 5 */
+	diskinfo[2] = capacity >> 11;
+
 	/* override with calculated, extended default, or driver values */
 	if (host->hostt->bios_param)
-		host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
+		host->hostt->bios_param(sdp, bdev, capacity, diskinfo);
 	else
-		scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
+		scsicam_bios_param(bdev, capacity, diskinfo);
 
 	geo->heads = diskinfo[0];
 	geo->sectors = diskinfo[1];
@@ -2337,14 +2338,6 @@ got_data:
 	if (sdkp->capacity > 0xffffffff)
 		sdp->use_16_for_rw = 1;
 
-	/* Rescale capacity to 512-byte units */
-	if (sector_size == 4096)
-		sdkp->capacity <<= 3;
-	else if (sector_size == 2048)
-		sdkp->capacity <<= 2;
-	else if (sector_size == 1024)
-		sdkp->capacity <<= 1;
-
 	blk_queue_physical_block_size(sdp->request_queue,
 				      sdkp->physical_block_size);
 	sdkp->device->sector_size = sector_size;
@@ -2812,11 +2805,6 @@ static int sd_try_extended_inquiry(struct scsi_device *sdp)
 	return 0;
 }
 
-static inline u32 logical_to_sectors(struct scsi_device *sdev, u32 blocks)
-{
-	return blocks << (ilog2(sdev->sector_size) - 9);
-}
-
 /**
  *	sd_revalidate_disk - called the first time a new disk is seen,
  *	performs disk spin up, read_capacity, etc.
@@ -2900,7 +2888,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
 	/* Combine with controller limits */
 	q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q));
 
-	set_capacity(disk, sdkp->capacity);
+	set_capacity(disk, logical_to_sectors(sdp, sdkp->capacity));
 	sd_config_write_same(sdkp);
 	kfree(buffer);