| Message ID | 20181219143934.3910-1-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | bsg: deprecate BIDI support in bsg | expand |
On Wed, 2018-12-19 at 15:39 +0100, Christoph Hellwig wrote: > Besides the OSD command set that never got traction, the only SCSI > command using bidirectional buffers is XDWRITEREAD in the 10 and 32 > byte variants, which is extremely esoteric. It probably doesn't make > sense to keep the support code around just for that, so start > deprecating the support. You may want to add to the patch description that the XDWRITEREAD command has been removed from the latest version of SBC-4 (SBC4r15). Bart.
On 12/19/18 7:39 AM, Christoph Hellwig wrote: > Besides the OSD command set that never got traction, the only SCSI > command using bidirectional buffers is XDWRITEREAD in the 10 and 32 > byte variants, which is extremely esoteric. It probably doesn't make > sense to keep the support code around just for that, so start > deprecating the support. Acked-by: Jens Axboe <axboe@kernel.dk>
On Wed, Dec 19, 2018 at 03:07:11PM -0800, Bart Van Assche wrote: > On Wed, 2018-12-19 at 15:39 +0100, Christoph Hellwig wrote: > > Besides the OSD command set that never got traction, the only SCSI > > command using bidirectional buffers is XDWRITEREAD in the 10 and 32 > > byte variants, which is extremely esoteric. It probably doesn't make > > sense to keep the support code around just for that, so start > > deprecating the support. > > You may want to add to the patch description that the XDWRITEREAD command > has been removed from the latest version of SBC-4 (SBC4r15). Oh, I didn't even noticed that, thanks!
On Wed, Dec 19, 2018 at 04:23:14PM -0700, Jens Axboe wrote: > On 12/19/18 7:39 AM, Christoph Hellwig wrote: > > Besides the OSD command set that never got traction, the only SCSI > > command using bidirectional buffers is XDWRITEREAD in the 10 and 32 > > byte variants, which is extremely esoteric. It probably doesn't make > > sense to keep the support code around just for that, so start > > deprecating the support. > > Acked-by: Jens Axboe <axboe@kernel.dk> You are the bsg maintainer, so I expected you to pick it up :)
On 12/20/18 12:12 AM, Christoph Hellwig wrote: > On Wed, Dec 19, 2018 at 04:23:14PM -0700, Jens Axboe wrote: >> On 12/19/18 7:39 AM, Christoph Hellwig wrote: >>> Besides the OSD command set that never got traction, the only SCSI >>> command using bidirectional buffers is XDWRITEREAD in the 10 and 32 >>> byte variants, which is extremely esoteric. It probably doesn't make >>> sense to keep the support code around just for that, so start >>> deprecating the support. >> >> Acked-by: Jens Axboe <axboe@kernel.dk> > > You are the bsg maintainer, so I expected you to pick it up :) OK - did you to amend the commit message to reflect the death of XDWRITEREAD as well?
On 2018-12-20 12:09 p.m., Jens Axboe wrote: > On 12/20/18 12:12 AM, Christoph Hellwig wrote: >> On Wed, Dec 19, 2018 at 04:23:14PM -0700, Jens Axboe wrote: >>> On 12/19/18 7:39 AM, Christoph Hellwig wrote: >>>> Besides the OSD command set that never got traction, the only SCSI >>>> command using bidirectional buffers is XDWRITEREAD in the 10 and 32 >>>> byte variants, which is extremely esoteric. It probably doesn't make >>>> sense to keep the support code around just for that, so start >>>> deprecating the support. >>> >>> Acked-by: Jens Axboe <axboe@kernel.dk> >> >> You are the bsg maintainer, so I expected you to pick it up :) > > OK - did you to amend the commit message to reflect the death of > XDWRITEREAD as well? > It was made obsolete in _draft_ sbc4r15.pdf according to my notes. It is not "dead", not until SBC-4 is ratified. Until then, SBC-3 is the current SCSI "block" device standard and it is there as a non-mandatory command. Doug Gilbert
diff --git a/block/bsg.c b/block/bsg.c index 9a442c23a715..60b41bf79e16 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -177,6 +177,10 @@ bsg_map_hdr(struct request_queue *q, struct sg_io_v4 *hdr, fmode_t mode) goto out; } + pr_warn_once( + "BIDI support in bsg has been deprecated and might be removed. " + "Please report your use case to linux-scsi@vger.kernel.org\n"); + next_rq = blk_get_request(q, REQ_OP_SCSI_IN, 0); if (IS_ERR(next_rq)) { ret = PTR_ERR(next_rq);
Besides the OSD command set that never got traction, the only SCSI command using bidirectional buffers is XDWRITEREAD in the 10 and 32 byte variants, which is extremely esoteric. It probably doesn't make sense to keep the support code around just for that, so start deprecating the support. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bsg.c | 4 ++++ 1 file changed, 4 insertions(+)