block: split scsi_request out of struct request

And require all drivers that want to support BLOCK_PC to allocate it
as the first thing of their private data.  To support this the legacy
IDE and BSG code is switched to set cmd_size on their queues to let
the block layer allocate the additional space.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 43 insertions, 48 deletions

diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 9cbd217bc0c9..6eb98725e194 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -121,7 +121,7 @@ static int cdrom_log_sense(ide_drive_t *drive, struct request *rq)
 		 * don't log START_STOP unit with LoEj set, since we cannot
 		 * reliably check if drive can auto-close
 		 */
-		if (rq->cmd[0] == GPCMD_START_STOP_UNIT && sense->asc == 0x24)
+		if (scsi_req(rq)->cmd[0] == GPCMD_START_STOP_UNIT && sense->asc == 0x24)
 			break;
 		log = 1;
 		break;
@@ -163,7 +163,7 @@ static void cdrom_analyze_sense_data(ide_drive_t *drive,
 	 * toc has not been recorded yet, it will fail with 05/24/00 (which is a
 	 * confusing error)
 	 */
-	if (failed_command && failed_command->cmd[0] == GPCMD_READ_TOC_PMA_ATIP)
+	if (failed_command && scsi_req(failed_command)->cmd[0] == GPCMD_READ_TOC_PMA_ATIP)
 		if (sense->sense_key == 0x05 && sense->asc == 0x24)
 			return;
 
@@ -219,15 +219,12 @@ static void ide_cd_complete_failed_rq(ide_drive_t *drive, struct request *rq)
 	void *sense = bio_data(rq->bio);
 
 	if (failed) {
-		if (failed->sense) {
-			/*
-			 * Sense is always read into drive->sense_data.
-			 * Copy back if the failed request has its
-			 * sense pointer set.
-			 */
-			memcpy(failed->sense, sense, 18);
-			failed->sense_len = rq->sense_len;
-		}
+		/*
+		 * Sense is always read into drive->sense_data, copy back to the
+		 * original request.
+		 */
+		memcpy(scsi_req(failed)->sense, sense, 18);
+		scsi_req(failed)->sense_len = scsi_req(rq)->sense_len;
 		cdrom_analyze_sense_data(drive, failed);
 
 		if (ide_end_rq(drive, failed, -EIO, blk_rq_bytes(failed)))
@@ -338,7 +335,7 @@ static int cdrom_decode_status(ide_drive_t *drive, u8 stat)
 		 *
 		 * cdrom_log_sense() knows this!
 		 */
-		if (rq->cmd[0] == GPCMD_START_STOP_UNIT)
+		if (scsi_req(rq)->cmd[0] == GPCMD_START_STOP_UNIT)
 			break;
 		/* fall-through */
 	case DATA_PROTECT:
@@ -414,7 +411,7 @@ static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct ide_cmd *cmd)
 	 * Some of the trailing request sense fields are optional,
 	 * and some drives don't send them.  Sigh.
 	 */
-	if (rq->cmd[0] == GPCMD_REQUEST_SENSE &&
+	if (scsi_req(rq)->cmd[0] == GPCMD_REQUEST_SENSE &&
 	    cmd->nleft > 0 && cmd->nleft <= 5)
 		cmd->nleft = 0;
 }
@@ -425,12 +422,8 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
 		    req_flags_t rq_flags)
 {
 	struct cdrom_info *info = drive->driver_data;
-	struct request_sense local_sense;
 	int retries = 10;
-	req_flags_t flags = 0;
-
-	if (!sense)
-		sense = &local_sense;
+	bool failed;
 
 	ide_debug_log(IDE_DBG_PC, "cmd[0]: 0x%x, write: 0x%x, timeout: %d, "
 				  "rq_flags: 0x%x",
@@ -440,12 +433,12 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
 	do {
 		struct request *rq;
 		int error;
+		bool delay = false;
 
 		rq = blk_get_request(drive->queue, write, __GFP_RECLAIM);
-
-		memcpy(rq->cmd, cmd, BLK_MAX_CDB);
+		scsi_req_init(rq);
+		memcpy(scsi_req(rq)->cmd, cmd, BLK_MAX_CDB);
 		rq->cmd_type = REQ_TYPE_ATA_PC;
-		rq->sense = sense;
 		rq->rq_flags |= rq_flags;
 		rq->timeout = timeout;
 		if (buffer) {
@@ -460,21 +453,21 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
 		error = blk_execute_rq(drive->queue, info->disk, rq, 0);
 
 		if (buffer)
-			*bufflen = rq->resid_len;
-
-		flags = rq->rq_flags;
-		blk_put_request(rq);
+			*bufflen = scsi_req(rq)->resid_len;
+		if (sense)
+			memcpy(sense, scsi_req(rq)->sense, sizeof(*sense));
 
 		/*
 		 * FIXME: we should probably abort/retry or something in case of
 		 * failure.
 		 */
-		if (flags & RQF_FAILED) {
+		failed = (rq->rq_flags & RQF_FAILED) != 0;
+		if (failed) {
 			/*
 			 * The request failed.  Retry if it was due to a unit
 			 * attention status (usually means media was changed).
 			 */
-			struct request_sense *reqbuf = sense;
+			struct request_sense *reqbuf = scsi_req(rq)->sense;
 
 			if (reqbuf->sense_key == UNIT_ATTENTION)
 				cdrom_saw_media_change(drive);
@@ -485,19 +478,20 @@ int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
 				 * a disk.  Retry, but wait a little to give
 				 * the drive time to complete the load.
 				 */
-				ssleep(2);
+				delay = true;
 			} else {
 				/* otherwise, don't retry */
 				retries = 0;
 			}
 			--retries;
 		}
-
-		/* end of retry loop */
-	} while ((flags & RQF_FAILED) && retries >= 0);
+		blk_put_request(rq);
+		if (delay)
+			ssleep(2);
+	} while (failed && retries >= 0);
 
 	/* return an error if the command failed */
-	return (flags & RQF_FAILED) ? -EIO : 0;
+	return failed ? -EIO : 0;
 }
 
 /*
@@ -636,7 +630,7 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
 		len -= blen;
 
 		if (sense && write == 0)
-			rq->sense_len += blen;
+			scsi_req(rq)->sense_len += blen;
 	}
 
 	/* pad, if necessary */
@@ -664,7 +658,7 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
 
 out_end:
 	if (rq->cmd_type == REQ_TYPE_BLOCK_PC && rc == 0) {
-		rq->resid_len = 0;
+		scsi_req(rq)->resid_len = 0;
 		blk_end_request_all(rq, 0);
 		hwif->rq = NULL;
 	} else {
@@ -685,9 +679,9 @@ out_end:
 
 		/* make sure it's fully ended */
 		if (rq->cmd_type != REQ_TYPE_FS) {
-			rq->resid_len -= cmd->nbytes - cmd->nleft;
+			scsi_req(rq)->resid_len -= cmd->nbytes - cmd->nleft;
 			if (uptodate == 0 && (cmd->tf_flags & IDE_TFLAG_WRITE))
-				rq->resid_len += cmd->last_xfer_len;
+				scsi_req(rq)->resid_len += cmd->last_xfer_len;
 		}
 
 		ide_complete_rq(drive, uptodate ? 0 : -EIO, blk_rq_bytes(rq));
@@ -1312,28 +1306,29 @@ static int ide_cdrom_prep_fs(struct request_queue *q, struct request *rq)
 	int hard_sect = queue_logical_block_size(q);
 	long block = (long)blk_rq_pos(rq) / (hard_sect >> 9);
 	unsigned long blocks = blk_rq_sectors(rq) / (hard_sect >> 9);
+	struct scsi_request *req = scsi_req(rq);
 
-	memset(rq->cmd, 0, BLK_MAX_CDB);
+	memset(req->cmd, 0, BLK_MAX_CDB);
 
 	if (rq_data_dir(rq) == READ)
-		rq->cmd[0] = GPCMD_READ_10;
+		req->cmd[0] = GPCMD_READ_10;
 	else
-		rq->cmd[0] = GPCMD_WRITE_10;
+		req->cmd[0] = GPCMD_WRITE_10;
 
 	/*
 	 * fill in lba
 	 */
-	rq->cmd[2] = (block >> 24) & 0xff;
-	rq->cmd[3] = (block >> 16) & 0xff;
-	rq->cmd[4] = (block >>  8) & 0xff;
-	rq->cmd[5] = block & 0xff;
+	req->cmd[2] = (block >> 24) & 0xff;
+	req->cmd[3] = (block >> 16) & 0xff;
+	req->cmd[4] = (block >>  8) & 0xff;
+	req->cmd[5] = block & 0xff;
 
 	/*
 	 * and transfer length
 	 */
-	rq->cmd[7] = (blocks >> 8) & 0xff;
-	rq->cmd[8] = blocks & 0xff;
-	rq->cmd_len = 10;
+	req->cmd[7] = (blocks >> 8) & 0xff;
+	req->cmd[8] = blocks & 0xff;
+	req->cmd_len = 10;
 	return BLKPREP_OK;
 }
 
@@ -1343,7 +1338,7 @@ static int ide_cdrom_prep_fs(struct request_queue *q, struct request *rq)
  */
 static int ide_cdrom_prep_pc(struct request *rq)
 {
-	u8 *c = rq->cmd;
+	u8 *c = scsi_req(rq)->cmd;
 
 	/* transform 6-byte read/write commands to the 10-byte version */
 	if (c[0] == READ_6 || c[0] == WRITE_6) {
@@ -1354,7 +1349,7 @@ static int ide_cdrom_prep_pc(struct request *rq)
 		c[2] = 0;
 		c[1] &= 0xe0;
 		c[0] += (READ_10 - READ_6);
-		rq->cmd_len = 10;
+		scsi_req(rq)->cmd_len = 10;
 		return BLKPREP_OK;
 	}