* [PATCH] Try #2: Use SCSI read/write(16) with >2TB drives [not found] <50A2F12F.9060209 () redhat ! com> @ 2012-11-14 5:55 ` Jason J. Herne 2012-11-14 19:02 ` Sebastian Andrzej Siewior 0 siblings, 1 reply; 3+ messages in thread From: Jason J. Herne @ 2012-11-14 5:55 UTC (permalink / raw) To: linux-scsi; +Cc: linux-usb, pbonzini, JBottomley, stern, Jason J. Herne From: "Jason J. Herne" <hernejj@gmail.com> Force large capacity (> 2TB) 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. Signed-off-by: Jason J. Herne <hernejj@gmail.com> --- drivers/scsi/sd.c | 5 ++++- include/scsi/scsi_device.h | 1 + 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 12f6fdf..9611d6b 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -887,7 +887,7 @@ 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; @@ -2054,6 +2054,9 @@ got_data: } } + /* Use read/write(16) for > 2TB disks */ + 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 88fae8d..19ab8f1 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -135,6 +135,7 @@ struct scsi_device { * because we did a bus reset. */ unsigned use_10_for_rw:1; /* first try 10-byte read / write */ unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */ + 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 */ -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] Try #2: Use SCSI read/write(16) with >2TB drives 2012-11-14 5:55 ` [PATCH] Try #2: Use SCSI read/write(16) with >2TB drives Jason J. Herne @ 2012-11-14 19:02 ` Sebastian Andrzej Siewior 2012-11-14 22:06 ` Jason J. Herne 0 siblings, 1 reply; 3+ messages in thread From: Sebastian Andrzej Siewior @ 2012-11-14 19:02 UTC (permalink / raw) To: Jason J. Herne; +Cc: linux-scsi, linux-usb, pbonzini, JBottomley, stern On Wed, Nov 14, 2012 at 12:55:13AM -0500, Jason J. Herne wrote: > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -887,7 +887,7 @@ 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; > @@ -2054,6 +2054,9 @@ got_data: > } > } > > + /* Use read/write(16) for > 2TB disks */ > + sdp->use_16_for_rw = (sdkp->capacity > 0xffffffff); The comment is pointless if you assume the reading is able to read C. What would help is a link either here or in patch's description to the mail thread where it has been descovered that some >2TB devices don't recognize the small command. > + > /* Rescale capacity to 512-byte units */ > if (sector_size == 4096) > sdkp->capacity <<= 3; Sebastian ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] Try #2: Use SCSI read/write(16) with >2TB drives 2012-11-14 19:02 ` Sebastian Andrzej Siewior @ 2012-11-14 22:06 ` Jason J. Herne 0 siblings, 0 replies; 3+ messages in thread From: Jason J. Herne @ 2012-11-14 22:06 UTC (permalink / raw) To: Sebastian Andrzej Siewior Cc: linux-scsi, linux-usb, Paolo Bonzini, JBottomley, Alan Stern On Wed, Nov 14, 2012 at 2:02 PM, Sebastian Andrzej Siewior <sebastian@breakpoint.cc> wrote: > On Wed, Nov 14, 2012 at 12:55:13AM -0500, Jason J. Herne wrote: >> } >> } >> >> + /* Use read/write(16) for > 2TB disks */ >> + sdp->use_16_for_rw = (sdkp->capacity > 0xffffffff); > > The comment is pointless if you assume the reading is able to read C. What > would help is a link either here or in patch's description to the mail thread > where it has been descovered that some >2TB devices don't recognize the small > command. I've removed the comment entirely and added a link to the original post within the patch description. Resending in separate e-mail. -- - Jason J. Herne (hernejj@gmail.com) ^ permalink raw reply [flat|nested] 3+ messages in thread
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2012-11-14 5:55 ` [PATCH] Try #2: Use SCSI read/write(16) with >2TB drives Jason J. Herne
2012-11-14 19:02 ` Sebastian Andrzej Siewior
2012-11-14 22:06 ` Jason J. Herne
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