From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: [PATCH] SG_IO ioctl in block layer against lk 2.5.55 Date: Fri, 10 Jan 2003 22:37:49 +1100 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3E1EB08D.5060105@torque.net> Reply-To: dougg@torque.net Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------070405040703090908060002" Return-path: List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org Cc: axboe@suse.de This is a multi-part message in MIME format. --------------070405040703090908060002 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit The attachment modifies the SG_IO ioctl that is in the block layer to: - convey the SCSI status value back via the sg_io_hdr structure - in the event of CHECK CONDITION, convey the sense buffer back via the sg_io_hdr structure - set "output" fields in sg_io_hdr structure to sane values - modify the errno behaviour to be more like the SCSI generic driver's SG_IO ioctl This patch was presented around lk 2.5.51 but fell between the cracks. The only modification is to take account of the changes to scsi/scsi_lib.c since then. Doug Gilbert --------------070405040703090908060002 Content-Type: text/plain; name="blk_sgio_2555.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="blk_sgio_2555.diff" --- linux/drivers/block/scsi_ioctl.c 2002-11-29 09:27:35.000000000 +1100 +++ linux/drivers/block/scsi_ioctl.c2551sgio2 2002-12-14 23:18:46.000000000 +1100 @@ -40,6 +40,11 @@ #define BLK_DEFAULT_TIMEOUT (60 * HZ) +/* defined in ../scsi/scsi.h ... should it be included? */ +#ifndef SCSI_SENSE_BUFFERSIZE +#define SCSI_SENSE_BUFFERSIZE 64 +#endif + int blk_do_rq(request_queue_t *q, struct block_device *bdev, struct request *rq) { DECLARE_COMPLETION(wait); @@ -126,11 +131,11 @@ struct sg_io_hdr *uptr) { unsigned long uaddr, start_time; - int err, reading, writing, nr_sectors; + int reading, writing, nr_sectors; struct sg_io_hdr hdr; struct request *rq; struct bio *bio; - char sense[24]; + char sense[SCSI_SENSE_BUFFERSIZE]; void *buffer; if (!access_ok(VERIFY_WRITE, uptr, sizeof(*uptr))) @@ -265,26 +270,36 @@ start_time = jiffies; - /* - * return -EIO if we didn't transfer all data, caller can look at - * residual count to find out how much did succeed + /* ignore return value. All information is passed back to caller + * (if he doesn't check that is his problem). + * N.B. a non-zero SCSI status is _not_ necessarily an error. */ - err = blk_do_rq(q, bdev, rq); - if (rq->data_len > 0) - err = -EIO; + blk_do_rq(q, bdev, rq); if (bio) { bio_unmap_user(bio, reading); bio_put(bio); } - hdr.status = rq->errors; + /* write to all output members */ + hdr.status = rq->errors; + hdr.masked_status = (hdr.status >> 1) & 0x1f; + hdr.msg_status = 0; + hdr.host_status = 0; + hdr.driver_status = 0; + hdr.info = 0; + if (hdr.masked_status || hdr.host_status || hdr.driver_status) + hdr.info |= SG_INFO_CHECK; hdr.resid = rq->data_len; hdr.duration = (jiffies - start_time) * (1000 / HZ); + hdr.sb_len_wr = 0; if (rq->sense_len && hdr.sbp) { - if (!copy_to_user(hdr.sbp,rq->sense, rq->sense_len)) - hdr.sb_len_wr = rq->sense_len; + int len = (hdr.mx_sb_len < rq->sense_len) ? + hdr.mx_sb_len : rq->sense_len; + + if (!copy_to_user(hdr.sbp, rq->sense, len)) + hdr.sb_len_wr = len; } blk_put_request(rq); @@ -297,8 +312,9 @@ kfree(buffer); } - - return err; + /* may not have succeeded, but output values written to control + * structure (struct sg_io_hdr). */ + return 0; } #define FORMAT_UNIT_TIMEOUT (2 * 60 * 60 * HZ) --- linux/drivers/scsi/scsi_lib.c 2002-12-10 17:38:29.000000000 +1100 +++ linux/drivers/scsi/scsi_lib.c2551sgio 2002-12-14 23:08:25.000000000 +1100 @@ -495,6 +495,7 @@ int this_count = SCpnt->bufflen >> 9; request_queue_t *q = SCpnt->device->request_queue; struct request *req = SCpnt->request; + int clear_errors = 1; /* * We must do one of several things here: @@ -528,10 +529,22 @@ kfree(SCpnt->buffer); } - if (blk_pc_request(req)) { - req->errors = result & 0xff; - if (!result) + if (blk_pc_request(req)) { /* SG_IO ioctl from block level */ + req->errors = (driver_byte(result) & DRIVER_SENSE) ? + (CHECK_CONDITION << 1) : (result & 0xff); + if (!result) req->data_len -= SCpnt->bufflen; + else { + clear_errors = 0; + if (SCpnt->sense_buffer[0] & 0x70) { + int len = 8 + SCpnt->sense_buffer[7]; + + if (len > SCSI_SENSE_BUFFERSIZE) + len = SCSI_SENSE_BUFFERSIZE; + memcpy(req->sense, SCpnt->sense_buffer, len); + req->sense_len = len; + } + } } /* @@ -552,7 +565,8 @@ req->nr_sectors, good_sectors)); SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n ", SCpnt->use_sg)); - req->errors = 0; + if (clear_errors) + req->errors = 0; /* * If multiple sectors are requested in one buffer, then * they will have been finished off by the first command. --------------070405040703090908060002--