[SCSI] sd: Use SCSI read/write(16) with > 32-bit LBA drives

Force large capacity (> 0xFFFFFFFF blocks) drives to use READ/WRITE(16) instead
of READ/WRITE(10). Some(most/all?) USB enclosures do not like READ(10) commands
when a large capacity drive is installed. This issue was reported and discussed
here: http://marc.info/?l=linux-usb&m=135247705222324

Signed-off-by: Jason J. Herne <hernejj@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index a45e12ac7e28511e9ed8ed4eae1e05834db30f68..c5a189c50286d1c1537a842ffe6f403a49951295 100644 (file)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1011,7 +1011,7 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
                SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
                SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
                SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
-       } else if (block > 0xffffffff) {
+       } else if (sdp->use_16_for_rw) {
                SCpnt->cmnd[0] += READ_16 - READ_6;
                SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
                SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
@@ -2203,6 +2203,8 @@ got_data:
                }
        }
 
+       sdp->use_16_for_rw = (sdkp->capacity > 0xffffffff);
+
        /* Rescale capacity to 512-byte units */
        if (sector_size == 4096)
                sdkp->capacity <<= 3;

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 55367b04dc9445e142369e98d2134d459eb5ef83..e65c62e82c5a6db8577667faabe95539f3893b47 100644 (file)
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -137,6 +137,7 @@ struct scsi_device {
        unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
        unsigned no_report_opcodes:1;   /* no REPORT SUPPORTED OPERATION CODES */
        unsigned no_write_same:1;       /* no WRITE SAME command */
+       unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
        unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
        unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
        unsigned skip_vpd_pages:1;      /* do not read VPD pages */