From 53ad570be625045aba3ae7de8d82401364c655e1 Mon Sep 17 00:00:00 2001 From: "Jason J. Herne" Date: Wed, 14 Nov 2012 17:03:22 -0500 Subject: [PATCH] [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 Signed-off-by: James Bottomley --- drivers/scsi/sd.c | 4 +++- include/scsi/scsi_device.h | 1 + 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index a45e12ac7e28..c5a189c50286 100644 --- 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 @@ sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer) } } + 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 55367b04dc94..e65c62e82c5a 100644 --- 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 */