sd: Disable support for 256 byte/sector disks

commit 74856fbf441929918c49ff262ace9835048e4e6a upstream.

256 bytes per sector support has been broken since 2.6.X,
and no-one stepped up to fix this.
So disable support for it.

Signed-off-by: Mark Hounschell <dmarkh@cfl.rr.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 5c6b5f5..a50825b 100644 (file)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1338,6 +1338,7 @@ static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
 {
        u64 start_lba = blk_rq_pos(scmd->request);
        u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
+       u64 factor = scmd->device->sector_size / 512;
        u64 bad_lba;
        int info_valid;
        /*
@@ -1359,16 +1360,9 @@ static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
        if (scsi_bufflen(scmd) <= scmd->device->sector_size)
                return 0;
 
-       if (scmd->device->sector_size < 512) {
-               /* only legitimate sector_size here is 256 */
-               start_lba <<= 1;
-               end_lba <<= 1;
-       } else {
-               /* be careful ... don't want any overflows */
-               u64 factor = scmd->device->sector_size / 512;
-               do_div(start_lba, factor);
-               do_div(end_lba, factor);
-       }
+       /* be careful ... don't want any overflows */
+       do_div(start_lba, factor);
+       do_div(end_lba, factor);
 
        /* The bad lba was reported incorrectly, we have no idea where
         * the error is.
@@ -1895,8 +1889,7 @@ got_data:
        if (sector_size != 512 &&
            sector_size != 1024 &&
            sector_size != 2048 &&
-           sector_size != 4096 &&
-           sector_size != 256) {
+           sector_size != 4096) {
                sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
                          sector_size);
                /*
@@ -1945,8 +1938,6 @@ got_data:
                sdkp->capacity <<= 2;
        else if (sector_size == 1024)
                sdkp->capacity <<= 1;
-       else if (sector_size == 256)
-               sdkp->capacity >>= 1;
 
        blk_queue_physical_block_size(sdp->request_queue,
                                      sdkp->physical_block_size);