Commit 53ad570b authored by Jason J. Herne's avatar Jason J. Herne Committed by James Bottomley
Browse files

[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: default avatarJason J. Herne <hernejj@gmail.com>
Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
parent 0b433447

drivers/scsi/sd.c

+3 −1
Original line number Diff line number Diff line
@@ -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;

include/scsi/scsi_device.h

+1 −0
Original line number Diff line number Diff line
@@ -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 */

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