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>

3 files changed, 24 insertions, 21 deletions

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index e5c5b8eb14a9..b93bb73b49d2 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -52,6 +52,7 @@
 #include <scsi/scsi.h>
 #include <scsi/sg.h>
 #include <scsi/scsi_ioctl.h>
+#include <scsi/scsi_request.h>
 #include <linux/cdrom.h>
 #include <linux/scatterlist.h>
 #include <linux/kthread.h>
@@ -1854,7 +1855,7 @@ static void cciss_softirq_done(struct request *rq)
 
 	/* set the residual count for pc requests */
 	if (rq->cmd_type == REQ_TYPE_BLOCK_PC)
-		rq->resid_len = c->err_info->ResidualCnt;
+		scsi_req(rq)->resid_len = c->err_info->ResidualCnt;
 
 	blk_end_request_all(rq, (rq->errors == 0) ? 0 : -EIO);
 
@@ -1941,9 +1942,16 @@ static void cciss_get_serial_no(ctlr_info_t *h, int logvol,
 static int cciss_add_disk(ctlr_info_t *h, struct gendisk *disk,
 				int drv_index)
 {
-	disk->queue = blk_init_queue(do_cciss_request, &h->lock);
+	disk->queue = blk_alloc_queue(GFP_KERNEL);
 	if (!disk->queue)
 		goto init_queue_failure;
+
+	disk->queue->cmd_size = sizeof(struct scsi_request);
+	disk->queue->request_fn = do_cciss_request;
+	disk->queue->queue_lock = &h->lock;
+	if (blk_init_allocated_queue(disk->queue) < 0)
+		goto cleanup_queue;
+
 	sprintf(disk->disk_name, "cciss/c%dd%d", h->ctlr, drv_index);
 	disk->major = h->major;
 	disk->first_minor = drv_index << NWD_SHIFT;
@@ -3111,15 +3119,7 @@ static inline int evaluate_target_status(ctlr_info_t *h,
 		return error_value;
 	}
 
-	/* SG_IO or similar, copy sense data back */
-	if (cmd->rq->sense) {
-		if (cmd->rq->sense_len > cmd->err_info->SenseLen)
-			cmd->rq->sense_len = cmd->err_info->SenseLen;
-		memcpy(cmd->rq->sense, cmd->err_info->SenseInfo,
-			cmd->rq->sense_len);
-	} else
-		cmd->rq->sense_len = 0;
-
+	scsi_req(cmd->rq)->sense_len = cmd->err_info->SenseLen;
 	return error_value;
 }
 
@@ -3150,7 +3150,6 @@ static inline void complete_command(ctlr_info_t *h, CommandList_struct *cmd,
 			dev_warn(&h->pdev->dev, "cmd %p has"
 			       " completed with data underrun "
 			       "reported\n", cmd);
-			cmd->rq->resid_len = cmd->err_info->ResidualCnt;
 		}
 		break;
 	case CMD_DATA_OVERRUN:
@@ -3426,8 +3425,9 @@ static void do_cciss_request(struct request_queue *q)
 			c->Request.CDB[14] = c->Request.CDB[15] = 0;
 		}
 	} else if (creq->cmd_type == REQ_TYPE_BLOCK_PC) {
-		c->Request.CDBLen = creq->cmd_len;
-		memcpy(c->Request.CDB, creq->cmd, BLK_MAX_CDB);
+		c->Request.CDBLen = scsi_req(creq)->cmd_len;
+		memcpy(c->Request.CDB, scsi_req(creq)->cmd, BLK_MAX_CDB);
+		scsi_req(creq)->sense = c->err_info->SenseInfo;
 	} else {
 		dev_warn(&h->pdev->dev, "bad request type %d\n",
 			creq->cmd_type);
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 1b94c1ca5c5f..918a92ccd0c0 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -707,7 +707,7 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *
 			     WRITE : READ, __GFP_RECLAIM);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
-	blk_rq_set_block_pc(rq);
+	scsi_req_init(rq);
 
 	if (cgc->buflen) {
 		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
@@ -716,8 +716,8 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *
 			goto out;
 	}
 
-	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
-	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
+	scsi_req(rq)->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
+	memcpy(scsi_req(rq)->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 
 	rq->timeout = 60*HZ;
 	if (cgc->quiet)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 10332c24f961..3027d2efc5d8 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -52,6 +52,7 @@ struct virtio_blk {
 };
 
 struct virtblk_req {
+	struct scsi_request sreq;	/* for SCSI passthrough */
 	struct request *req;
 	struct virtio_blk_outhdr out_hdr;
 	struct virtio_scsi_inhdr in_hdr;
@@ -91,7 +92,7 @@ static int __virtblk_add_req(struct virtqueue *vq,
 	 * inhdr with additional status information.
 	 */
 	if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) {
-		sg_init_one(&cmd, vbr->req->cmd, vbr->req->cmd_len);
+		sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len);
 		sgs[num_out++] = &cmd;
 	}
 
@@ -103,7 +104,6 @@ static int __virtblk_add_req(struct virtqueue *vq,
 	}
 
 	if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) {
-		memcpy(vbr->sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
 		sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE);
 		sgs[num_out + num_in++] = &sense;
 		sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
@@ -123,8 +123,10 @@ static inline void virtblk_request_done(struct request *req)
 	int error = virtblk_result(vbr);
 
 	if (req->cmd_type == REQ_TYPE_BLOCK_PC) {
-		req->resid_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual);
-		req->sense_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len);
+		scsi_req(req)->resid_len =
+			virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual);
+		vbr->sreq.sense_len =
+			virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len);
 		req->errors = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors);
 	} else if (req->cmd_type == REQ_TYPE_DRV_PRIV) {
 		req->errors = (error != 0);
@@ -538,6 +540,7 @@ static int virtblk_init_request(void *data, struct request *rq,
 	struct virtio_blk *vblk = data;
 	struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq);
 
+	vbr->sreq.sense = vbr->sense;
 	sg_init_table(vbr->sg, vblk->sg_elems);
 	return 0;
 }