Convert drivers to blk-mq

index f68e9baffad7..bf51a2307ce1 100644
@@ -6,7 +6,7 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/hdreg.h>
 #include <linux/genhd.h>
 #include <linux/cdrom.h>

@@ -66,9 +66,10 @@ struct vdc_port {
 
 	u64			max_xfer_size;
 	u32			vdisk_block_size;
+	u32			drain;
 
 	u64			ldc_timeout;
-	struct timer_list	ldc_reset_timer;
+	struct delayed_work	ldc_reset_timer_work;
 	struct work_struct	ldc_reset_work;
 
 	/* The server fills these in for us in the disk attribute

@@ -80,12 +81,14 @@ struct vdc_port {
 	u8			vdisk_mtype;
 	u32			vdisk_phys_blksz;
 
+	struct blk_mq_tag_set	tag_set;
+
 	char			disk_name[32];
 };
 
 static void vdc_ldc_reset(struct vdc_port *port);
 static void vdc_ldc_reset_work(struct work_struct *work);
-static void vdc_ldc_reset_timer(struct timer_list *t);
+static void vdc_ldc_reset_timer_work(struct work_struct *work);
 
 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
 {

@@ -175,11 +178,8 @@ static void vdc_blk_queue_start(struct vdc_port *port)
 	 * handshake completes, so check for initial handshake before we've
 	 * allocated a disk.
 	 */
-	if (port->disk && blk_queue_stopped(port->disk->queue) &&
-	    vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50) {
-		blk_start_queue(port->disk->queue);
-	}
-
+	if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
+		blk_mq_start_hw_queues(port->disk->queue);
 }
 
 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)

@@ -197,7 +197,7 @@ static void vdc_handshake_complete(struct vio_driver_state *vio)
 {
 	struct vdc_port *port = to_vdc_port(vio);
 
-	del_timer(&port->ldc_reset_timer);
+	cancel_delayed_work(&port->ldc_reset_timer_work);
 	vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 	vdc_blk_queue_start(port);
 }

@@ -320,7 +320,7 @@ static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 
 	rqe->req = NULL;
 
-	__blk_end_request(req, (desc->status ? BLK_STS_IOERR : 0), desc->size);
+	blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0);
 
 	vdc_blk_queue_start(port);
 }

@@ -525,29 +525,40 @@ static int __send_request(struct request *req)
 	return err;
 }
 
-static void do_vdc_request(struct request_queue *rq)
+static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd)
 {
-	struct request *req;
+	struct vdc_port *port = hctx->queue->queuedata;
+	struct vio_dring_state *dr;
+	unsigned long flags;
 
-	while ((req = blk_peek_request(rq)) != NULL) {
-		struct vdc_port *port;
-		struct vio_dring_state *dr;
+	dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 
-		port = req->rq_disk->private_data;
-		dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-		if (unlikely(vdc_tx_dring_avail(dr) < 1))
-			goto wait;
+	blk_mq_start_request(bd->rq);
 
-		blk_start_request(req);
+	spin_lock_irqsave(&port->vio.lock, flags);
 
-		if (__send_request(req) < 0) {
-			blk_requeue_request(rq, req);
-wait:
-			/* Avoid pointless unplugs. */
-			blk_stop_queue(rq);
-			break;
-		}
+	/*
+	 * Doing drain, just end the request in error
+	 */
+	if (unlikely(port->drain)) {
+		spin_unlock_irqrestore(&port->vio.lock, flags);
+		return BLK_STS_IOERR;
 	}
+
+	if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
+		spin_unlock_irqrestore(&port->vio.lock, flags);
+		blk_mq_stop_hw_queue(hctx);
+		return BLK_STS_DEV_RESOURCE;
+	}
+
+	if (__send_request(bd->rq) < 0) {
+		spin_unlock_irqrestore(&port->vio.lock, flags);
+		return BLK_STS_IOERR;
+	}
+
+	spin_unlock_irqrestore(&port->vio.lock, flags);
+	return BLK_STS_OK;
 }
 
 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)

@@ -759,6 +770,44 @@ static void vdc_port_down(struct vdc_port *port)
 	vio_ldc_free(&port->vio);
 }
 
+static const struct blk_mq_ops vdc_mq_ops = {
+	.queue_rq	= vdc_queue_rq,
+};
+
+static void cleanup_queue(struct request_queue *q)
+{
+	struct vdc_port *port = q->queuedata;
+
+	blk_mq_free_tag_set(&port->tag_set);
+	blk_cleanup_queue(q);
+}
+
+static struct request_queue *init_queue(struct vdc_port *port)
+{
+	struct blk_mq_tag_set *set = &port->tag_set;
+	struct request_queue *q;
+	int ret;
+
+	set->ops = &vdc_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = VDC_TX_RING_SIZE;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE;
+
+	ret = blk_mq_alloc_tag_set(set);
+	if (ret)
+		return ERR_PTR(ret);
+
+	q = blk_mq_init_queue(set);
+	if (IS_ERR(q)) {
+		blk_mq_free_tag_set(set);
+		return q;
+	}
+
+	q->queuedata = port;
+	return q;
+}
+
 static int probe_disk(struct vdc_port *port)
 {
 	struct request_queue *q;

@@ -796,17 +845,17 @@ static int probe_disk(struct vdc_port *port)
 				    (u64)geom.num_sec);
 	}
 
-	q = blk_init_queue(do_vdc_request, &port->vio.lock);
-	if (!q) {
+	q = init_queue(port);
+	if (IS_ERR(q)) {
 		printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 		       port->vio.name);
-		return -ENOMEM;
+		return PTR_ERR(q);
 	}
 	g = alloc_disk(1 << PARTITION_SHIFT);
 	if (!g) {
 		printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 		       port->vio.name);
-		blk_cleanup_queue(q);
+		cleanup_queue(q);
 		return -ENOMEM;
 	}
 

@@ -981,7 +1030,7 @@ static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	 */
 	ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
 	port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
-	timer_setup(&port->ldc_reset_timer, vdc_ldc_reset_timer, 0);
+	INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
 	INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
 
 	err = vio_driver_init(&port->vio, vdev, VDEV_DISK,

@@ -1034,18 +1083,14 @@ static int vdc_port_remove(struct vio_dev *vdev)
 	struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 
 	if (port) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&port->vio.lock, flags);
-		blk_stop_queue(port->disk->queue);
-		spin_unlock_irqrestore(&port->vio.lock, flags);
+		blk_mq_stop_hw_queues(port->disk->queue);
 
 		flush_work(&port->ldc_reset_work);
-		del_timer_sync(&port->ldc_reset_timer);
+		cancel_delayed_work_sync(&port->ldc_reset_timer_work);
 		del_timer_sync(&port->vio.timer);
 
 		del_gendisk(port->disk);
-		blk_cleanup_queue(port->disk->queue);
+		cleanup_queue(port->disk->queue);
 		put_disk(port->disk);
 		port->disk = NULL;
 

@@ -1080,32 +1125,46 @@ static void vdc_requeue_inflight(struct vdc_port *port)
 		}
 
 		rqe->req = NULL;
-		blk_requeue_request(port->disk->queue, req);
+		blk_mq_requeue_request(req, false);
 	}
 }
 
 static void vdc_queue_drain(struct vdc_port *port)
 {
-	struct request *req;
+	struct request_queue *q = port->disk->queue;
 
-	while ((req = blk_fetch_request(port->disk->queue)) != NULL)
-		__blk_end_request_all(req, BLK_STS_IOERR);
+	/*
+	 * Mark the queue as draining, then freeze/quiesce to ensure
+	 * that all existing requests are seen in ->queue_rq() and killed
+	 */
+	port->drain = 1;
+	spin_unlock_irq(&port->vio.lock);
+
+	blk_mq_freeze_queue(q);
+	blk_mq_quiesce_queue(q);
+
+	spin_lock_irq(&port->vio.lock);
+	port->drain = 0;
+	blk_mq_unquiesce_queue(q);
+	blk_mq_unfreeze_queue(q);
 }
 
-static void vdc_ldc_reset_timer(struct timer_list *t)
+static void vdc_ldc_reset_timer_work(struct work_struct *work)
 {
-	struct vdc_port *port = from_timer(port, t, ldc_reset_timer);
-	struct vio_driver_state *vio = &port->vio;
-	unsigned long flags;
+	struct vdc_port *port;
+	struct vio_driver_state *vio;
 
-	spin_lock_irqsave(&vio->lock, flags);
+	port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
+	vio = &port->vio;
+
+	spin_lock_irq(&vio->lock);
 	if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
 		pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
 			port->disk_name, port->ldc_timeout);
 		vdc_queue_drain(port);
 		vdc_blk_queue_start(port);
 	}
-	spin_unlock_irqrestore(&vio->lock, flags);
+	spin_unlock_irq(&vio->lock);
 }
 
 static void vdc_ldc_reset_work(struct work_struct *work)

@@ -1129,7 +1188,7 @@ static void vdc_ldc_reset(struct vdc_port *port)
 	assert_spin_locked(&port->vio.lock);
 
 	pr_warn(PFX "%s ldc link reset\n", port->disk_name);
-	blk_stop_queue(port->disk->queue);
+	blk_mq_stop_hw_queues(port->disk->queue);
 	vdc_requeue_inflight(port);
 	vdc_port_down(port);
 

@@ -1146,7 +1205,7 @@ static void vdc_ldc_reset(struct vdc_port *port)
 	}
 
 	if (port->ldc_timeout)
-		mod_timer(&port->ldc_reset_timer,
+		mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
 			  round_jiffies(jiffies + HZ * port->ldc_timeout));
 	mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
 	return;

index 4d90e5eba2f5..5402dfdf331b 100644
@@ -16,7 +16,7 @@
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/sched.h>
 #include <linux/interrupt.h>
 #include <linux/compiler.h>

@@ -244,6 +244,7 @@ struct carm_port {
 	unsigned int			port_no;
 	struct gendisk			*disk;
 	struct carm_host		*host;
+	struct blk_mq_tag_set		tag_set;
 
 	/* attached device characteristics */
 	u64				capacity;

@@ -279,6 +280,7 @@ struct carm_host {
 	unsigned int			state;
 	u32				fw_ver;
 
+	struct blk_mq_tag_set		tag_set;
 	struct request_queue		*oob_q;
 	unsigned int			n_oob;
 

@@ -750,7 +752,7 @@ static inline void carm_end_request_queued(struct carm_host *host,
 	struct request *req = crq->rq;
 	int rc;
 
-	__blk_end_request_all(req, error);
+	blk_mq_end_request(req, error);
 
 	rc = carm_put_request(host, crq);
 	assert(rc == 0);

@@ -760,7 +762,7 @@ static inline void carm_push_q (struct carm_host *host, struct request_queue *q)
 {
 	unsigned int idx = host->wait_q_prod % CARM_MAX_WAIT_Q;
 
-	blk_stop_queue(q);
+	blk_mq_stop_hw_queues(q);
 	VPRINTK("STOPPED QUEUE %p\n", q);
 
 	host->wait_q[idx] = q;

@@ -785,7 +787,7 @@ static inline void carm_round_robin(struct carm_host *host)
 {
 	struct request_queue *q = carm_pop_q(host);
 	if (q) {
-		blk_start_queue(q);
+		blk_mq_start_hw_queues(q);
 		VPRINTK("STARTED QUEUE %p\n", q);
 	}
 }

@@ -802,62 +804,62 @@ static inline void carm_end_rq(struct carm_host *host, struct carm_request *crq,
 	}
 }
 
-static void carm_oob_rq_fn(struct request_queue *q)
+static blk_status_t carm_oob_queue_rq(struct blk_mq_hw_ctx *hctx,
+				      const struct blk_mq_queue_data *bd)
 {
+	struct request_queue *q = hctx->queue;
 	struct carm_host *host = q->queuedata;
 	struct carm_request *crq;
-	struct request *rq;
 	int rc;
 
-	while (1) {
-		DPRINTK("get req\n");
-		rq = blk_fetch_request(q);
-		if (!rq)
-			break;
+	blk_mq_start_request(bd->rq);
+
+	spin_lock_irq(&host->lock);
 
-		crq = rq->special;
-		assert(crq != NULL);
-		assert(crq->rq == rq);
+	crq = bd->rq->special;
+	assert(crq != NULL);
+	assert(crq->rq == bd->rq);
 
-		crq->n_elem = 0;
+	crq->n_elem = 0;
 
-		DPRINTK("send req\n");
-		rc = carm_send_msg(host, crq);
-		if (rc) {
-			blk_requeue_request(q, rq);
-			carm_push_q(host, q);
-			return;		/* call us again later, eventually */
-		}
+	DPRINTK("send req\n");
+	rc = carm_send_msg(host, crq);
+	if (rc) {
+		carm_push_q(host, q);
+		spin_unlock_irq(&host->lock);
+		return BLK_STS_DEV_RESOURCE;
 	}
+
+	spin_unlock_irq(&host->lock);
+	return BLK_STS_OK;
 }
 
-static void carm_rq_fn(struct request_queue *q)
+static blk_status_t carm_queue_rq(struct blk_mq_hw_ctx *hctx,
+				  const struct blk_mq_queue_data *bd)
 {
+	struct request_queue *q = hctx->queue;
 	struct carm_port *port = q->queuedata;
 	struct carm_host *host = port->host;
 	struct carm_msg_rw *msg;
 	struct carm_request *crq;
-	struct request *rq;
+	struct request *rq = bd->rq;
 	struct scatterlist *sg;
 	int writing = 0, pci_dir, i, n_elem, rc;
 	u32 tmp;
 	unsigned int msg_size;
 
-queue_one_request:
-	VPRINTK("get req\n");
-	rq = blk_peek_request(q);
-	if (!rq)
-		return;
+	blk_mq_start_request(rq);
+
+	spin_lock_irq(&host->lock);
 
 	crq = carm_get_request(host);
 	if (!crq) {
 		carm_push_q(host, q);
-		return;		/* call us again later, eventually */
+		spin_unlock_irq(&host->lock);
+		return BLK_STS_DEV_RESOURCE;
 	}
 	crq->rq = rq;
 
-	blk_start_request(rq);
-
 	if (rq_data_dir(rq) == WRITE) {
 		writing = 1;
 		pci_dir = PCI_DMA_TODEVICE;

@@ -869,15 +871,19 @@ static void carm_rq_fn(struct request_queue *q)
 	sg = &crq->sg[0];
 	n_elem = blk_rq_map_sg(q, rq, sg);
 	if (n_elem <= 0) {
+		/* request with no s/g entries? */
 		carm_end_rq(host, crq, BLK_STS_IOERR);
-		return;		/* request with no s/g entries? */
+		spin_unlock_irq(&host->lock);
+		return BLK_STS_IOERR;
 	}
 
 	/* map scatterlist to PCI bus addresses */
 	n_elem = pci_map_sg(host->pdev, sg, n_elem, pci_dir);
 	if (n_elem <= 0) {
+		/* request with no s/g entries? */
 		carm_end_rq(host, crq, BLK_STS_IOERR);
-		return;		/* request with no s/g entries? */
+		spin_unlock_irq(&host->lock);
+		return BLK_STS_IOERR;
 	}
 	crq->n_elem = n_elem;
 	crq->port = port;

@@ -927,12 +933,13 @@ static void carm_rq_fn(struct request_queue *q)
 	rc = carm_send_msg(host, crq);
 	if (rc) {
 		carm_put_request(host, crq);
-		blk_requeue_request(q, rq);
 		carm_push_q(host, q);
-		return;		/* call us again later, eventually */
+		spin_unlock_irq(&host->lock);
+		return BLK_STS_DEV_RESOURCE;
 	}
 
-	goto queue_one_request;
+	spin_unlock_irq(&host->lock);
+	return BLK_STS_OK;
 }
 
 static void carm_handle_array_info(struct carm_host *host,

@@ -1485,6 +1492,14 @@ static int carm_init_host(struct carm_host *host)
 	return 0;
 }
 
+static const struct blk_mq_ops carm_oob_mq_ops = {
+	.queue_rq	= carm_oob_queue_rq,
+};
+
+static const struct blk_mq_ops carm_mq_ops = {
+	.queue_rq	= carm_queue_rq,
+};
+
 static int carm_init_disks(struct carm_host *host)
 {
 	unsigned int i;

@@ -1494,6 +1509,7 @@ static int carm_init_disks(struct carm_host *host)
 		struct gendisk *disk;
 		struct request_queue *q;
 		struct carm_port *port;
+		struct blk_mq_tag_set *set;
 
 		port = &host->port[i];
 		port->host = host;

@@ -1513,9 +1529,19 @@ static int carm_init_disks(struct carm_host *host)
 		disk->fops = &carm_bd_ops;
 		disk->private_data = port;
 
-		q = blk_init_queue(carm_rq_fn, &host->lock);
-		if (!q) {
-			rc = -ENOMEM;
+		set = &port->tag_set;
+		set->ops = &carm_mq_ops;
+		set->nr_hw_queues = 1;
+		set->queue_depth = max_queue;
+		set->numa_node = NUMA_NO_NODE;
+		set->flags = BLK_MQ_F_SHOULD_MERGE;
+		rc = blk_mq_alloc_tag_set(set);
+		if (rc)
+			break;
+
+		q = blk_mq_init_queue(set);
+		if (IS_ERR(q)) {
+			rc = PTR_ERR(q);
 			break;
 		}
 		disk->queue = q;

@@ -1533,14 +1559,18 @@ static void carm_free_disks(struct carm_host *host)
 	unsigned int i;
 
 	for (i = 0; i < CARM_MAX_PORTS; i++) {
-		struct gendisk *disk = host->port[i].disk;
+		struct carm_port *port = &host->port[i];
+		struct gendisk *disk = port->disk;
+
 		if (disk) {
 			struct request_queue *q = disk->queue;
 
 			if (disk->flags & GENHD_FL_UP)
 				del_gendisk(disk);
-			if (q)
+			if (q) {
+				blk_mq_free_tag_set(&port->tag_set);
 				blk_cleanup_queue(q);
+			}
 			put_disk(disk);
 		}
 	}

@@ -1568,6 +1598,7 @@ static int carm_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
 	unsigned int pci_dac;
 	int rc;
 	struct request_queue *q;
+	struct blk_mq_tag_set *set;
 	unsigned int i;
 
 	printk_once(KERN_DEBUG DRV_NAME " version " DRV_VERSION "\n");

@@ -1636,11 +1667,21 @@ static int carm_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto err_out_iounmap;
 	}
 
-	q = blk_init_queue(carm_oob_rq_fn, &host->lock);
-	if (!q) {
+	set = &host->tag_set;
+	set->ops = &carm_oob_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 1;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_NO_SCHED;
+	rc = blk_mq_alloc_tag_set(set);
+	if (rc)
+		goto err_out_pci_free;
+
+	q = blk_mq_init_queue(set);
+	if (IS_ERR(q)) {
 		printk(KERN_ERR DRV_NAME "(%s): OOB queue alloc failure\n",
 		       pci_name(pdev));
-		rc = -ENOMEM;
+		rc = PTR_ERR(q);
 		goto err_out_pci_free;
 	}
 	host->oob_q = q;

@@ -1704,6 +1745,7 @@ static int carm_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
 		clear_bit(0, &carm_major_alloc);
 	else if (host->major == 161)
 		clear_bit(1, &carm_major_alloc);
+	blk_mq_free_tag_set(&host->tag_set);
 	blk_cleanup_queue(host->oob_q);
 err_out_pci_free:
 	pci_free_consistent(pdev, CARM_SHM_SIZE, host->shm, host->shm_dma);

@@ -1735,6 +1777,7 @@ static void carm_remove_one (struct pci_dev *pdev)
 		clear_bit(0, &carm_major_alloc);
 	else if (host->major == 161)
 		clear_bit(1, &carm_major_alloc);
+	blk_mq_free_tag_set(&host->tag_set);
 	blk_cleanup_queue(host->oob_q);
 	pci_free_consistent(pdev, CARM_SHM_SIZE, host->shm, host->shm_dma);
 	iounmap(host->mmio);

index afe1508d82c6..e8b41e95a679 100644
@@ -19,7 +19,7 @@
  */
 
 #include <linux/ata.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 

@@ -42,6 +42,7 @@
 struct ps3disk_private {
 	spinlock_t lock;		/* Request queue spinlock */
 	struct request_queue *queue;
+	struct blk_mq_tag_set tag_set;
 	struct gendisk *gendisk;
 	unsigned int blocking_factor;
 	struct request *req;

@@ -118,8 +119,8 @@ static void ps3disk_scatter_gather(struct ps3_storage_device *dev,
 	}
 }
 
-static int ps3disk_submit_request_sg(struct ps3_storage_device *dev,
-				     struct request *req)
+static void ps3disk_submit_request_sg(struct ps3_storage_device *dev,
+				      struct request *req)
 {
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 	int write = rq_data_dir(req), res;

@@ -158,16 +159,15 @@ static int ps3disk_submit_request_sg(struct ps3_storage_device *dev,
 	if (res) {
 		dev_err(&dev->sbd.core, "%s:%u: %s failed %d\n", __func__,
 			__LINE__, op, res);
-		__blk_end_request_all(req, BLK_STS_IOERR);
-		return 0;
+		blk_mq_end_request(req, BLK_STS_IOERR);
+		return;
 	}
 
 	priv->req = req;
-	return 1;
 }
 
-static int ps3disk_submit_flush_request(struct ps3_storage_device *dev,
-					struct request *req)
+static void ps3disk_submit_flush_request(struct ps3_storage_device *dev,
+					 struct request *req)
 {
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 	u64 res;

@@ -180,50 +180,46 @@ static int ps3disk_submit_flush_request(struct ps3_storage_device *dev,
 	if (res) {
 		dev_err(&dev->sbd.core, "%s:%u: sync cache failed 0x%llx\n",
 			__func__, __LINE__, res);
-		__blk_end_request_all(req, BLK_STS_IOERR);
-		return 0;
+		blk_mq_end_request(req, BLK_STS_IOERR);
+		return;
 	}
 
 	priv->req = req;
-	return 1;
 }
 
 static void ps3disk_do_request(struct ps3_storage_device *dev,
-			       struct request_queue *q)
+			       struct request *req)
 {
-	struct request *req;
-
 	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
 
-	while ((req = blk_fetch_request(q))) {
-		switch (req_op(req)) {
-		case REQ_OP_FLUSH:
-			if (ps3disk_submit_flush_request(dev, req))
-				return;
-			break;
-		case REQ_OP_READ:
-		case REQ_OP_WRITE:
-			if (ps3disk_submit_request_sg(dev, req))
-				return;
-			break;
-		default:
-			blk_dump_rq_flags(req, DEVICE_NAME " bad request");
-			__blk_end_request_all(req, BLK_STS_IOERR);
-		}
+	switch (req_op(req)) {
+	case REQ_OP_FLUSH:
+		ps3disk_submit_flush_request(dev, req);
+		break;
+	case REQ_OP_READ:
+	case REQ_OP_WRITE:
+		ps3disk_submit_request_sg(dev, req);
+		break;
+	default:
+		blk_dump_rq_flags(req, DEVICE_NAME " bad request");
+		blk_mq_end_request(req, BLK_STS_IOERR);
 	}
 }
 
-static void ps3disk_request(struct request_queue *q)
+static blk_status_t ps3disk_queue_rq(struct blk_mq_hw_ctx *hctx,
+				     const struct blk_mq_queue_data *bd)
 {
+	struct request_queue *q = hctx->queue;
 	struct ps3_storage_device *dev = q->queuedata;
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 
-	if (priv->req) {
-		dev_dbg(&dev->sbd.core, "%s:%u busy\n", __func__, __LINE__);
-		return;
-	}
+	blk_mq_start_request(bd->rq);
+
+	spin_lock_irq(&priv->lock);
+	ps3disk_do_request(dev, bd->rq);
+	spin_unlock_irq(&priv->lock);
 
-	ps3disk_do_request(dev, q);
+	return BLK_STS_OK;
 }
 
 static irqreturn_t ps3disk_interrupt(int irq, void *data)

@@ -279,12 +275,13 @@ static irqreturn_t ps3disk_interrupt(int irq, void *data)
 			ps3disk_scatter_gather(dev, req, 0);
 	}
 
+	blk_mq_end_request(req, error);
+
 	spin_lock(&priv->lock);
-	__blk_end_request_all(req, error);
 	priv->req = NULL;
-	ps3disk_do_request(dev, priv->queue);
 	spin_unlock(&priv->lock);
 
+	blk_mq_start_hw_queues(priv->queue);
 	return IRQ_HANDLED;
 }
 

@@ -404,6 +401,10 @@ static unsigned long ps3disk_mask;
 
 static DEFINE_MUTEX(ps3disk_mask_mutex);
 
+static const struct blk_mq_ops ps3disk_mq_ops = {
+	.queue_rq	= ps3disk_queue_rq,
+};
+
 static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 {
 	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);

@@ -411,6 +412,7 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 	int error;
 	unsigned int devidx;
 	struct request_queue *queue;
+	struct blk_mq_tag_set *set;
 	struct gendisk *gendisk;
 
 	if (dev->blk_size < 512) {

@@ -454,11 +456,21 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 
 	ps3disk_identify(dev);
 
-	queue = blk_init_queue(ps3disk_request, &priv->lock);
-	if (!queue) {
-		dev_err(&dev->sbd.core, "%s:%u: blk_init_queue failed\n",
+	set = &priv->tag_set;
+	set->ops = &ps3disk_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 2;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE;
+	error = blk_mq_alloc_tag_set(set);
+	if (error)
+		goto fail_teardown;
+
+	queue = blk_mq_init_queue(set);
+	if (IS_ERR(queue)) {
+		dev_err(&dev->sbd.core, "%s:%u: blk_mq_init_queue failed\n",
 			__func__, __LINE__);
-		error = -ENOMEM;
+		error = PTR_ERR(queue);
 		goto fail_teardown;
 	}
 

@@ -504,6 +516,7 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 	return 0;
 
 fail_cleanup_queue:
+	blk_mq_free_tag_set(&priv->tag_set);
 	blk_cleanup_queue(queue);
 fail_teardown:
 	ps3stor_teardown(dev);

index 5f777b694f3c..338ea9dc3393 100644
@@ -119,8 +119,8 @@ static void ps3disk_scatter_gather(struct ps3_storage_device *dev,
 	}
 }
 
-static void ps3disk_submit_request_sg(struct ps3_storage_device *dev,
-				      struct request *req)
+static blk_status_t ps3disk_submit_request_sg(struct ps3_storage_device *dev,
+					      struct request *req)
 {
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 	int write = rq_data_dir(req), res;

@@ -159,15 +159,15 @@ static void ps3disk_submit_request_sg(struct ps3_storage_device *dev,
 	if (res) {
 		dev_err(&dev->sbd.core, "%s:%u: %s failed %d\n", __func__,
 			__LINE__, op, res);
-		blk_mq_end_request(req, BLK_STS_IOERR);
-		return;
+		return BLK_STS_IOERR;
 	}
 
 	priv->req = req;
+	return BLK_STS_OK;
 }
 
-static void ps3disk_submit_flush_request(struct ps3_storage_device *dev,
-					 struct request *req)
+static blk_status_t ps3disk_submit_flush_request(struct ps3_storage_device *dev,
+						 struct request *req)
 {
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
 	u64 res;

@@ -180,29 +180,27 @@ static void ps3disk_submit_flush_request(struct ps3_storage_device *dev,
 	if (res) {
 		dev_err(&dev->sbd.core, "%s:%u: sync cache failed 0x%llx\n",
 			__func__, __LINE__, res);
-		blk_mq_end_request(req, BLK_STS_IOERR);
-		return;
+		return BLK_STS_IOERR;
 	}
 
 	priv->req = req;
+	return BLK_STS_OK;
 }
 
-static void ps3disk_do_request(struct ps3_storage_device *dev,
-			       struct request *req)
+static blk_status_t ps3disk_do_request(struct ps3_storage_device *dev,
+				       struct request *req)
 {
 	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
 
 	switch (req_op(req)) {
 	case REQ_OP_FLUSH:
-		ps3disk_submit_flush_request(dev, req);
-		break;
+		return ps3disk_submit_flush_request(dev, req);
 	case REQ_OP_READ:
 	case REQ_OP_WRITE:
-		ps3disk_submit_request_sg(dev, req);
-		break;
+		return ps3disk_submit_request_sg(dev, req);
 	default:
 		blk_dump_rq_flags(req, DEVICE_NAME " bad request");
-		blk_mq_end_request(req, BLK_STS_IOERR);
+		return BLK_STS_IOERR;
 	}
 }
 

@@ -212,14 +210,15 @@ static blk_status_t ps3disk_queue_rq(struct blk_mq_hw_ctx *hctx,
 	struct request_queue *q = hctx->queue;
 	struct ps3_storage_device *dev = q->queuedata;
 	struct ps3disk_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	blk_status_t ret;
 
 	blk_mq_start_request(bd->rq);
 
 	spin_lock_irq(&priv->lock);
-	ps3disk_do_request(dev, bd->rq);
+	ret = ps3disk_do_request(dev, bd->rq);
 	spin_unlock_irq(&priv->lock);
 
-	return BLK_STS_OK;
+	return ret;
 }
 
 static irqreturn_t ps3disk_interrupt(int irq, void *data)

@@ -281,7 +280,7 @@ static irqreturn_t ps3disk_interrupt(int irq, void *data)
 	priv->req = NULL;
 	spin_unlock(&priv->lock);
 
-	blk_mq_start_hw_queues(priv->queue);
+	blk_mq_run_hw_queues(priv->queue, true);
 	return IRQ_HANDLED;
 }
 

index c2ecd64a2403..dcf10e39995a 100644
@@ -2507,6 +2507,39 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
 }
 EXPORT_SYMBOL(blk_mq_init_queue);
 
+/*
+ * Helper for setting up a queue with mq ops, given queue depth, and
+ * the passed in mq ops flags.
+ */
+struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set,
+					   const struct blk_mq_ops *ops,
+					   unsigned int queue_depth,
+					   unsigned int set_flags)
+{
+	struct request_queue *q;
+	int ret;
+
+	memset(set, 0, sizeof(*set));
+	set->ops = ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = queue_depth;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = set_flags;
+
+	ret = blk_mq_alloc_tag_set(set);
+	if (ret)
+		return ERR_PTR(ret);
+
+	q = blk_mq_init_queue(set);
+	if (IS_ERR(q)) {
+		blk_mq_free_tag_set(set);
+		return q;
+	}
+
+	return q;
+}
+EXPORT_SYMBOL(blk_mq_init_sq_queue);
+
 static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
 {
 	int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);

index 1da59c16f637..2286dc12c6bc 100644
@@ -203,6 +203,10 @@ enum {
 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
 struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 						  struct request_queue *q);
+struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set,
+						const struct blk_mq_ops *ops,
+						unsigned int queue_depth,
+						unsigned int set_flags);
 int blk_mq_register_dev(struct device *, struct request_queue *);
 void blk_mq_unregister_dev(struct device *, struct request_queue *);
 

194 lines not on this page · raw message

@@ -274,10 +274,9 @@ static irqreturn_t ps3disk_interrupt(int irq, void *data)
                        ps3disk_scatter_gather(dev, req, 0);
        }
 
-       blk_mq_end_request(req, error);
-
        spin_lock(&priv->lock);
        priv->req = NULL;
+       blk_mq_end_request(req, error);
        spin_unlock(&priv->lock);
 
        blk_mq_run_hw_queues(priv->queue, true);

@@ -458,7 +457,7 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
        set = &priv->tag_set;
        set->ops = &ps3disk_mq_ops;
        set->nr_hw_queues = 1;
-       set->queue_depth = 2;
+       set->queue_depth = 1;
        set->numa_node = NUMA_NO_NODE;
        set->flags = BLK_MQ_F_SHOULD_MERGE;
        error = blk_mq_alloc_tag_set(set);

index a026211afb51..f2b82e3510d8 100644
@@ -137,7 +137,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_DLY};
 #include <linux/delay.h>
 #include <linux/cdrom.h>
 #include <linux/spinlock.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/mutex.h>
 #include <linux/uaccess.h>
 

@@ -186,7 +186,8 @@ static int pcd_packet(struct cdrom_device_info *cdi,
 static int pcd_detect(void);
 static void pcd_probe_capabilities(void);
 static void do_pcd_read_drq(void);
-static void do_pcd_request(struct request_queue * q);
+static blk_status_t pcd_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd);
 static void do_pcd_read(void);
 
 struct pcd_unit {

@@ -199,6 +200,8 @@ struct pcd_unit {
 	char *name;		/* pcd0, pcd1, etc */
 	struct cdrom_device_info info;	/* uniform cdrom interface */
 	struct gendisk *disk;
+	struct blk_mq_tag_set tag_set;
+	struct list_head rq_list;
 };
 
 static struct pcd_unit pcd[PCD_UNITS];

@@ -292,6 +295,10 @@ static const struct cdrom_device_ops pcd_dops = {
 			  CDC_CD_RW,
 };
 
+static const struct blk_mq_ops pcd_mq_ops = {
+	.queue_rq	= pcd_queue_rq,
+};
+
 static void pcd_init_units(void)
 {
 	struct pcd_unit *cd;

@@ -300,13 +307,29 @@ static void pcd_init_units(void)
 	pcd_drive_count = 0;
 	for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++) {
 		struct gendisk *disk = alloc_disk(1);
+		struct blk_mq_tag_set *set;
+
 		if (!disk)
 			continue;
-		disk->queue = blk_init_queue(do_pcd_request, &pcd_lock);
-		if (!disk->queue) {
-			put_disk(disk);
+
+		set = &cd->tag_set;
+		set->ops = &pcd_mq_ops;
+		set->nr_hw_queues = 1;
+		set->queue_depth = 1;
+		set->numa_node = NUMA_NO_NODE;
+		set->flags = BLK_MQ_F_SHOULD_MERGE;
+		if (blk_mq_alloc_tag_set(set))
+			continue;
+
+		disk->queue = blk_mq_init_queue(set);
+		if (IS_ERR(disk->queue)) {
+			blk_mq_free_tag_set(set);
+			disk->queue = NULL;
 			continue;
 		}
+
+		INIT_LIST_HEAD(&cd->rq_list);
+		disk->queue->queuedata = cd;
 		blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
 		cd->disk = disk;
 		cd->pi = &cd->pia;

@@ -748,18 +771,18 @@ static int pcd_queue;
 static int set_next_request(void)
 {
 	struct pcd_unit *cd;
-	struct request_queue *q;
 	int old_pos = pcd_queue;
 
 	do {
 		cd = &pcd[pcd_queue];
-		q = cd->present ? cd->disk->queue : NULL;
 		if (++pcd_queue == PCD_UNITS)
 			pcd_queue = 0;
-		if (q) {
-			pcd_req = blk_fetch_request(q);
-			if (pcd_req)
-				break;
+		if (cd->present && !list_empty(&cd->rq_list)) {
+			pcd_req = list_first_entry(&cd->rq_list, struct request,
+							queuelist);
+			list_del_init(&pcd_req->queuelist);
+			blk_mq_start_request(pcd_req);
+			break;
 		}
 	} while (pcd_queue != old_pos);
 

@@ -768,33 +791,41 @@ static int set_next_request(void)
 
 static void pcd_request(void)
 {
+	struct pcd_unit *cd;
+
 	if (pcd_busy)
 		return;
-	while (1) {
-		if (!pcd_req && !set_next_request())
-			return;
 
-		if (rq_data_dir(pcd_req) == READ) {
-			struct pcd_unit *cd = pcd_req->rq_disk->private_data;
-			if (cd != pcd_current)
-				pcd_bufblk = -1;
-			pcd_current = cd;
-			pcd_sector = blk_rq_pos(pcd_req);
-			pcd_count = blk_rq_cur_sectors(pcd_req);
-			pcd_buf = bio_data(pcd_req->bio);
-			pcd_busy = 1;
-			ps_set_intr(do_pcd_read, NULL, 0, nice);
-			return;
-		} else {
-			__blk_end_request_all(pcd_req, BLK_STS_IOERR);
-			pcd_req = NULL;
-		}
-	}
+	if (!pcd_req && !set_next_request())
+		return;
+
+	cd = pcd_req->rq_disk->private_data;
+	if (cd != pcd_current)
+		pcd_bufblk = -1;
+	pcd_current = cd;
+	pcd_sector = blk_rq_pos(pcd_req);
+	pcd_count = blk_rq_cur_sectors(pcd_req);
+	pcd_buf = bio_data(pcd_req->bio);
+	pcd_busy = 1;
+	ps_set_intr(do_pcd_read, NULL, 0, nice);
 }
 
-static void do_pcd_request(struct request_queue *q)
+static blk_status_t pcd_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd)
 {
+	struct pcd_unit *cd = hctx->queue->queuedata;
+
+	if (rq_data_dir(bd->rq) != READ) {
+		blk_mq_start_request(bd->rq);
+		return BLK_STS_IOERR;
+	}
+
+	spin_lock_irq(&pcd_lock);
+	list_add_tail(&bd->rq->queuelist, &cd->rq_list);
 	pcd_request();
+	spin_unlock_irq(&pcd_lock);
+
+	return BLK_STS_OK;
 }
 
 static inline void next_request(blk_status_t err)

@@ -802,8 +833,10 @@ static inline void next_request(blk_status_t err)
 	unsigned long saved_flags;
 
 	spin_lock_irqsave(&pcd_lock, saved_flags);
-	if (!__blk_end_request_cur(pcd_req, err))
+	if (!blk_update_request(pcd_req, err, blk_rq_cur_bytes(pcd_req))) {
+		__blk_mq_end_request(pcd_req, err);
 		pcd_req = NULL;
+	}
 	pcd_busy = 0;
 	pcd_request();
 	spin_unlock_irqrestore(&pcd_lock, saved_flags);

@@ -1010,6 +1043,7 @@ static void __exit pcd_exit(void)
 			pi_release(cd->pi);
 			unregister_cdrom(&cd->info);
 		}
+		blk_mq_free_tag_set(&cd->tag_set);
 		blk_cleanup_queue(cd->disk->queue);
 		put_disk(cd->disk);
 	}

index 7cf947586fe4..87636d6ce191 100644
@@ -151,7 +151,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_GEO, D_SBY, D_DLY, D_SLV};
 #include <linux/delay.h>
 #include <linux/hdreg.h>
 #include <linux/cdrom.h>	/* for the eject ioctl */
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/blkpg.h>
 #include <linux/kernel.h>
 #include <linux/mutex.h>

@@ -236,6 +236,7 @@ struct pd_unit {
 	int alt_geom;
 	char name[PD_NAMELEN];	/* pda, pdb, etc ... */
 	struct gendisk *gd;
+	struct blk_mq_tag_set tag_set;
 };
 
 static struct pd_unit pd[PD_UNITS];

@@ -355,25 +356,6 @@ enum action {Fail = 0, Ok = 1, Hold, Wait};
 static struct request *pd_req;	/* current request */
 static enum action (*phase)(void);
 
-static void run_fsm(void);
-
-static void ps_tq_int(struct work_struct *work);
-
-static DECLARE_DELAYED_WORK(fsm_tq, ps_tq_int);
-
-static void schedule_fsm(void)
-{
-	if (!nice)
-		schedule_delayed_work(&fsm_tq, 0);
-	else
-		schedule_delayed_work(&fsm_tq, nice-1);
-}
-
-static void ps_tq_int(struct work_struct *work)
-{
-	run_fsm();
-}
-
 static enum action do_pd_io_start(void);
 static enum action pd_special(void);
 static enum action do_pd_read_start(void);

@@ -387,7 +369,7 @@ static int pd_claimed;
 static struct pd_unit *pd_current; /* current request's drive */
 static PIA *pi_current; /* current request's PIA */
 
-static int set_next_request(void)
+static int run_next_queue(void)
 {
 	struct gendisk *disk;
 	struct request_queue *q;

@@ -398,11 +380,8 @@ static int set_next_request(void)
 		q = disk ? disk->queue : NULL;
 		if (++pd_queue == PD_UNITS)
 			pd_queue = 0;
-		if (q) {
-			pd_req = blk_fetch_request(q);
-			if (pd_req)
-				break;
-		}
+		if (q)
+			blk_mq_run_hw_queues(q, true);
 	} while (pd_queue != old_pos);
 
 	return pd_req != NULL;

@@ -438,17 +417,20 @@ static void run_fsm(void)
 				pd_claimed = 0;
 				phase = NULL;
 				spin_lock_irqsave(&pd_lock, saved_flags);
-				if (!__blk_end_request_cur(pd_req,
-						res == Ok ? 0 : BLK_STS_IOERR)) {
-					if (!set_next_request())
-						stop = 1;
+				if (!blk_update_request(pd_req,
+						res == Ok ? 0 : BLK_STS_IOERR,
+						blk_rq_cur_bytes(pd_req))) {
+					__blk_mq_end_request(pd_req,
+						res == Ok ? 0 : BLK_STS_IOERR);
+					run_next_queue();
+					stop = 1;
 				}
 				spin_unlock_irqrestore(&pd_lock, saved_flags);
 				if (stop)
 					return;
 				/* fall through */
 			case Hold:
-				schedule_fsm();
+				blk_mq_run_hw_queues(pd_req->q, true);
 				return;
 			case Wait:
 				pi_disconnect(pi_current);

@@ -505,11 +487,17 @@ static int pd_next_buf(void)
 	if (pd_count)
 		return 0;
 	spin_lock_irqsave(&pd_lock, saved_flags);
-	__blk_end_request_cur(pd_req, 0);
-	pd_count = blk_rq_cur_sectors(pd_req);
-	pd_buf = bio_data(pd_req->bio);
+	if (!blk_update_request(pd_req, 0, blk_rq_cur_bytes(pd_req))) {
+		__blk_mq_end_request(pd_req, 0);
+		pd_req = NULL;
+		pd_count = 0;
+		pd_buf = NULL;
+	} else {
+		pd_count = blk_rq_cur_sectors(pd_req);
+		pd_buf = bio_data(pd_req->bio);
+	}
 	spin_unlock_irqrestore(&pd_lock, saved_flags);
-	return 0;
+	return !pd_count;
 }
 
 static unsigned long pd_timeout;

@@ -726,15 +714,22 @@ static enum action pd_identify(struct pd_unit *disk)
 
 /* end of io request engine */
 
-static void do_pd_request(struct request_queue * q)
+static blk_status_t pd_queue_rq(struct blk_mq_hw_ctx *hctx,
+				const struct blk_mq_queue_data *bd)
 {
-	if (pd_req)
-		return;
-	pd_req = blk_fetch_request(q);
-	if (!pd_req)
-		return;
+	spin_lock_irq(&pd_lock);
 
-	schedule_fsm();
+	/* this should not be possible */
+	if (pd_req) {
+		spin_unlock_irq(&pd_lock);
+		return BLK_STS_DEV_RESOURCE;
+	}
+
+	pd_req = bd->rq;
+	spin_unlock_irq(&pd_lock);
+	blk_mq_start_request(bd->rq);
+	run_fsm();
+	return BLK_STS_OK;
 }
 
 static int pd_special_command(struct pd_unit *disk,

@@ -847,23 +842,42 @@ static const struct block_device_operations pd_fops = {
 
 /* probing */
 
+static const struct blk_mq_ops pd_mq_ops = {
+	.queue_rq	= pd_queue_rq,
+};
+
 static void pd_probe_drive(struct pd_unit *disk)
 {
-	struct gendisk *p = alloc_disk(1 << PD_BITS);
+	struct blk_mq_tag_set *set;
+	struct gendisk *p;
+
+	p = alloc_disk(1 << PD_BITS);
 	if (!p)
 		return;
+
 	strcpy(p->disk_name, disk->name);
 	p->fops = &pd_fops;
 	p->major = major;
 	p->first_minor = (disk - pd) << PD_BITS;
 	disk->gd = p;
 	p->private_data = disk;
-	p->queue = blk_init_queue(do_pd_request, &pd_lock);
-	if (!p->queue) {
-		disk->gd = NULL;
-		put_disk(p);
+
+	set = &disk->tag_set;
+	set->ops = &pd_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 1;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING;
+	if (blk_mq_alloc_tag_set(set))
+		return;
+
+	p->queue = blk_mq_init_queue(set);
+	if (IS_ERR(p->queue)) {
+		blk_mq_free_tag_set(set);
+		p->queue = NULL;
 		return;
 	}
+
 	blk_queue_max_hw_sectors(p->queue, cluster);
 	blk_queue_bounce_limit(p->queue, BLK_BOUNCE_HIGH);
 

@@ -971,6 +985,7 @@ static void __exit pd_exit(void)
 		if (p) {
 			disk->gd = NULL;
 			del_gendisk(p);
+			blk_mq_free_tag_set(&disk->tag_set);
 			blk_cleanup_queue(p->queue);
 			put_disk(p);
 			pi_release(disk->pi);

index eef7a91f667d..58866cf495f8 100644
@@ -152,7 +152,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_LUN, D_DLY};
 #include <linux/hdreg.h>
 #include <linux/cdrom.h>
 #include <linux/spinlock.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/blkpg.h>
 #include <linux/mutex.h>
 #include <linux/uaccess.h>

@@ -206,7 +206,8 @@ module_param_array(drive3, int, NULL, 0);
 #define ATAPI_WRITE_10		0x2a
 
 static int pf_open(struct block_device *bdev, fmode_t mode);
-static void do_pf_request(struct request_queue * q);
+static blk_status_t pf_queue_rq(struct blk_mq_hw_ctx *hctx,
+				const struct blk_mq_queue_data *bd);
 static int pf_ioctl(struct block_device *bdev, fmode_t mode,
 		    unsigned int cmd, unsigned long arg);
 static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo);

@@ -238,6 +239,8 @@ struct pf_unit {
 	int present;		/* device present ? */
 	char name[PF_NAMELEN];	/* pf0, pf1, ... */
 	struct gendisk *disk;
+	struct blk_mq_tag_set tag_set;
+	struct list_head rq_list;
 };
 
 static struct pf_unit units[PF_UNITS];

@@ -277,6 +280,10 @@ static const struct block_device_operations pf_fops = {
 	.check_events	= pf_check_events,
 };
 
+static const struct blk_mq_ops pf_mq_ops = {
+	.queue_rq	= pf_queue_rq,
+};
+
 static void __init pf_init_units(void)
 {
 	struct pf_unit *pf;

@@ -284,14 +291,34 @@ static void __init pf_init_units(void)
 
 	pf_drive_count = 0;
 	for (unit = 0, pf = units; unit < PF_UNITS; unit++, pf++) {
-		struct gendisk *disk = alloc_disk(1);
+		struct blk_mq_tag_set *set;
+		struct gendisk *disk;
+
+		disk = alloc_disk(1);
 		if (!disk)
 			continue;
-		disk->queue = blk_init_queue(do_pf_request, &pf_spin_lock);
-		if (!disk->queue) {
+
+		set = &pf->tag_set;
+		set->ops = &pf_mq_ops;
+		set->nr_hw_queues = 1;
+		set->queue_depth = 1;
+		set->numa_node = NUMA_NO_NODE;
+		set->flags = BLK_MQ_F_SHOULD_MERGE;
+		if (blk_mq_alloc_tag_set(set)) {
 			put_disk(disk);
-			return;
+			continue;
 		}
+
+		disk->queue = blk_mq_init_queue(set);
+		if (IS_ERR(disk->queue)) {
+			blk_mq_free_tag_set(set);
+			put_disk(disk);
+			disk->queue = NULL;
+			continue;
+		}
+
+		INIT_LIST_HEAD(&pf->rq_list);
+		disk->queue->queuedata = pf;
 		blk_queue_max_segments(disk->queue, cluster);
 		blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
 		pf->disk = disk;

@@ -784,18 +811,18 @@ static int pf_queue;
 static int set_next_request(void)
 {
 	struct pf_unit *pf;
-	struct request_queue *q;
 	int old_pos = pf_queue;
 
 	do {
 		pf = &units[pf_queue];
-		q = pf->present ? pf->disk->queue : NULL;
 		if (++pf_queue == PF_UNITS)
 			pf_queue = 0;
-		if (q) {
-			pf_req = blk_fetch_request(q);
-			if (pf_req)
-				break;
+		if (pf->present && !list_empty(&pf->rq_list)) {
+			pf_req = list_first_entry(&pf->rq_list, struct request,
+							queuelist);
+			list_del_init(&pf_req->queuelist);
+			blk_mq_start_request(pf_req);
+			break;
 		}
 	} while (pf_queue != old_pos);
 

@@ -804,8 +831,12 @@ static int set_next_request(void)
 
 static void pf_end_request(blk_status_t err)
 {
-	if (pf_req && !__blk_end_request_cur(pf_req, err))
+	if (!pf_req)
+		return;
+	if (!blk_update_request(pf_req, err, blk_rq_cur_bytes(pf_req))) {
+		__blk_mq_end_request(pf_req, err);
 		pf_req = NULL;
+	}
 }
 
 static void pf_request(void)

@@ -842,9 +873,17 @@ static void pf_request(void)
 	}
 }
 
-static void do_pf_request(struct request_queue *q)
+static blk_status_t pf_queue_rq(struct blk_mq_hw_ctx *hctx,
+				const struct blk_mq_queue_data *bd)
 {
+	struct pf_unit *pf = hctx->queue->queuedata;
+	
+	spin_lock_irq(&pf_spin_lock);
+	list_add_tail(&bd->rq->queuelist, &pf->rq_list);
 	pf_request();
+	spin_unlock_irq(&pf_spin_lock);
+
+	return BLK_STS_OK;
 }
 
 static int pf_next_buf(void)

@@ -1023,6 +1062,7 @@ static void __exit pf_exit(void)
 		if (!pf->present)
 			continue;
 		del_gendisk(pf->disk);
+		blk_mq_free_tag_set(&pf->tag_set);
 		blk_cleanup_queue(pf->disk->queue);
 		put_disk(pf->disk);
 		pi_release(pf->pi);

index 83c470364dfb..a302962a441d 100644
@@ -22,7 +22,7 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/ata.h>
 #include <linux/hdreg.h>
 #include <linux/cdrom.h>

@@ -156,6 +156,7 @@ struct ubd {
 	struct cow cow;
 	struct platform_device pdev;
 	struct request_queue *queue;
+	struct blk_mq_tag_set tag_set;
 	spinlock_t lock;
 	struct scatterlist sg[MAX_SG];
 	struct request *request;

@@ -436,7 +437,9 @@ __uml_help(udb_setup,
 "    in the boot output.\n\n"
 );
 
-static void do_ubd_request(struct request_queue * q);
+static void ubd_handle_request(struct ubd *dev);
+static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd);
 
 /* Only changed by ubd_init, which is an initcall. */
 static int thread_fd = -1;

@@ -520,12 +523,12 @@ static void ubd_handler(void)
 			return;
 		}
 		for (count = 0; count < n/sizeof(struct io_thread_req *); count++) {
-			blk_end_request(
-				(*irq_req_buffer)[count]->req,
-				BLK_STS_OK,
-				(*irq_req_buffer)[count]->length
-			);
-			kfree((*irq_req_buffer)[count]);
+			struct io_thread_req *io_req = (*irq_req_buffer)[count];
+
+			if (!blk_update_request(io_req->req, BLK_STS_OK, io_req->length))
+				__blk_mq_end_request(io_req->req, BLK_STS_OK);
+
+			kfree(io_req);
 		}
 	}
 	reactivate_fd(thread_fd, UBD_IRQ);

@@ -534,7 +537,7 @@ static void ubd_handler(void)
 		ubd = container_of(list, struct ubd, restart);
 		list_del_init(&ubd->restart);
 		spin_lock_irqsave(&ubd->lock, flags);
-		do_ubd_request(ubd->queue);
+		ubd_handle_request(ubd);
 		spin_unlock_irqrestore(&ubd->lock, flags);
 	}
 }

@@ -856,6 +859,7 @@ static void ubd_device_release(struct device *dev)
 {
 	struct ubd *ubd_dev = dev_get_drvdata(dev);
 
+	blk_mq_free_tag_set(&ubd_dev->tag_set);
 	blk_cleanup_queue(ubd_dev->queue);
 	*ubd_dev = ((struct ubd) DEFAULT_UBD);
 }

@@ -897,20 +901,25 @@ static int ubd_disk_register(int major, u64 size, int unit,
 	return 0;
 }
 
+static const struct blk_mq_ops ubd_mq_ops = {
+	.queue_rq	= ubd_queue_rq,
+};
+
 #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9))
 
 static int ubd_add(int n, char **error_out)
 {
 	struct ubd *ubd_dev = &ubd_devs[n];
+	struct blk_mq_tag_set *set;
 	int err = 0;
 
 	if(ubd_dev->file == NULL)
-		goto out;
+		goto out1;
 
 	err = ubd_file_size(ubd_dev, &ubd_dev->size);
 	if(err < 0){
 		*error_out = "Couldn't determine size of device's file";
-		goto out;
+		goto out1;
 	}
 
 	ubd_dev->size = ROUND_BLOCK(ubd_dev->size);

@@ -918,12 +927,26 @@ static int ubd_add(int n, char **error_out)
 	INIT_LIST_HEAD(&ubd_dev->restart);
 	sg_init_table(ubd_dev->sg, MAX_SG);
 
-	err = -ENOMEM;
-	ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock);
-	if (ubd_dev->queue == NULL) {
+	set = &ubd_dev->tag_set;
+	set->ops = &ubd_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 2;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE;
+	err = blk_mq_alloc_tag_set(set);
+	if (err) {
+		*error_out = "Failed to initialize device tag set";
+		goto out1;
+	}
+
+	ubd_dev->queue = blk_mq_init_queue(set);
+	if (IS_ERR(ubd_dev->queue)) {
+		err = PTR_ERR(ubd_dev->queue);
+		ubd_dev->queue = NULL;
 		*error_out = "Failed to initialize device queue";
 		goto out;
 	}
+
 	ubd_dev->queue->queuedata = ubd_dev;
 	blk_queue_write_cache(ubd_dev->queue, true, false);
 

@@ -947,9 +970,12 @@ static int ubd_add(int n, char **error_out)
 
 	err = 0;
 out:
+	blk_mq_free_tag_set(&ubd_dev->tag_set);
+out1:
 	return err;
 
 out_cleanup:
+	blk_mq_free_tag_set(&ubd_dev->tag_set);
 	blk_cleanup_queue(ubd_dev->queue);
 	goto out;
 }

@@ -1338,10 +1364,11 @@ static bool submit_request(struct io_thread_req *io_req, struct ubd *dev)
 	int n = os_write_file(thread_fd, &io_req,
 			     sizeof(io_req));
 	if (n != sizeof(io_req)) {
-		if (n != -EAGAIN)
+		if (n != -EAGAIN) {
 			printk("write to io thread failed, "
 			       "errno = %d\n", -n);
-		else if (list_empty(&dev->restart))
+			blk_mq_end_request(io_req->req, BLK_STS_IOERR);
+		} else if (list_empty(&dev->restart))
 			list_add(&dev->restart, &restart);
 
 		kfree(io_req);

@@ -1351,62 +1378,69 @@ static bool submit_request(struct io_thread_req *io_req, struct ubd *dev)
 }
 
 /* Called with dev->lock held */
-static void do_ubd_request(struct request_queue *q)
+static void ubd_handle_request(struct ubd *dev)
 {
+	struct request *req = dev->request;
 	struct io_thread_req *io_req;
-	struct request *req;
-
-	while(1){
-		struct ubd *dev = q->queuedata;
-		if(dev->request == NULL){
-			struct request *req = blk_fetch_request(q);
-			if(req == NULL)
-				return;
 
-			dev->request = req;
-			dev->rq_pos = blk_rq_pos(req);
-			dev->start_sg = 0;
-			dev->end_sg = blk_rq_map_sg(q, req, dev->sg);
+	if (req_op(req) == REQ_OP_FLUSH) {
+		io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC);
+		if (io_req == NULL) {
+			if (list_empty(&dev->restart))
+				list_add(&dev->restart, &restart);
+			return;
 		}
+		prepare_flush_request(req, io_req);
+		if (submit_request(io_req, dev) == false)
+			return;
+	}
 
-		req = dev->request;
+	while (dev->start_sg < dev->end_sg){
+		struct scatterlist *sg = &dev->sg[dev->start_sg];
 
-		if (req_op(req) == REQ_OP_FLUSH) {
-			io_req = kmalloc(sizeof(struct io_thread_req),
-					 GFP_ATOMIC);
-			if (io_req == NULL) {
-				if (list_empty(&dev->restart))
-					list_add(&dev->restart, &restart);
-				return;
-			}
-			prepare_flush_request(req, io_req);
-			if (submit_request(io_req, dev) == false)
-				return;
+		io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC);
+		if (io_req == NULL){
+			if (list_empty(&dev->restart))
+				list_add(&dev->restart, &restart);
+			return;
 		}
+		prepare_request(req, io_req,
+				(unsigned long long)dev->rq_pos << 9,
+				sg->offset, sg->length, sg_page(sg));
 
-		while(dev->start_sg < dev->end_sg){
-			struct scatterlist *sg = &dev->sg[dev->start_sg];
+		if (submit_request(io_req, dev) == false)
+			return;
 
-			io_req = kmalloc(sizeof(struct io_thread_req),
-					 GFP_ATOMIC);
-			if(io_req == NULL){
-				if(list_empty(&dev->restart))
-					list_add(&dev->restart, &restart);
-				return;
-			}
-			prepare_request(req, io_req,
-					(unsigned long long)dev->rq_pos << 9,
-					sg->offset, sg->length, sg_page(sg));
+		dev->rq_pos += sg->length >> 9;
+		dev->start_sg++;
+	}
 
-			if (submit_request(io_req, dev) == false)
-				return;
+	dev->end_sg = 0;
+	dev->request = NULL;
+}
 
-			dev->rq_pos += sg->length >> 9;
-			dev->start_sg++;
-		}
-		dev->end_sg = 0;
-		dev->request = NULL;
+static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd)
+{
+	struct ubd *dev = hctx->queue->queuedata;
+	struct request *req;
+
+	spin_lock_irq(&dev->lock);
+	if (dev->request != NULL) {
+		spin_unlock_irq(&dev->lock);
+		return BLK_STS_DEV_RESOURCE;
 	}
+
+	req = bd->rq;
+	blk_mq_start_request(req);
+	dev->request = req;
+	dev->rq_pos = blk_rq_pos(req);
+	dev->start_sg = 0;
+	dev->end_sg = blk_rq_map_sg(req->q, req, dev->sg);
+
+	ubd_handle_request(dev);
+	spin_unlock_irq(&dev->lock);
+	return BLK_STS_OK;
 }
 
 static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo)

index 716fc8ed31d3..b829f55ff577 100644
@@ -15,7 +15,7 @@
 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
 
 #include <linux/module.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/memstick.h>
 #include <linux/idr.h>
 #include <linux/hdreg.h>

@@ -1873,69 +1873,65 @@ static void msb_io_work(struct work_struct *work)
 	struct msb_data *msb = container_of(work, struct msb_data, io_work);
 	int page, error, len;
 	sector_t lba;
-	unsigned long flags;
 	struct scatterlist *sg = msb->prealloc_sg;
+	struct request *req;
 
 	dbg_verbose("IO: work started");
 
 	while (1) {
-		spin_lock_irqsave(&msb->q_lock, flags);
+		spin_lock_irq(&msb->q_lock);
 
 		if (msb->need_flush_cache) {
 			msb->need_flush_cache = false;
-			spin_unlock_irqrestore(&msb->q_lock, flags);
+			spin_unlock_irq(&msb->q_lock);
 			msb_cache_flush(msb);
 			continue;
 		}
 
-		if (!msb->req) {
-			msb->req = blk_fetch_request(msb->queue);
-			if (!msb->req) {
-				dbg_verbose("IO: no more requests exiting");
-				spin_unlock_irqrestore(&msb->q_lock, flags);
-				return;
-			}
+		req = msb->req;
+		if (!req) {
+			dbg_verbose("IO: no more requests exiting");
+			spin_unlock_irq(&msb->q_lock);
+			return;
 		}
 
-		spin_unlock_irqrestore(&msb->q_lock, flags);
-
-		/* If card was removed meanwhile */
-		if (!msb->req)
-			return;
+		spin_unlock_irq(&msb->q_lock);
 
 		/* process the request */
 		dbg_verbose("IO: processing new request");
-		blk_rq_map_sg(msb->queue, msb->req, sg);
+		blk_rq_map_sg(msb->queue, req, sg);
 
-		lba = blk_rq_pos(msb->req);
+		lba = blk_rq_pos(req);
 
 		sector_div(lba, msb->page_size / 512);
 		page = sector_div(lba, msb->pages_in_block);
 
 		if (rq_data_dir(msb->req) == READ)
 			error = msb_do_read_request(msb, lba, page, sg,
-				blk_rq_bytes(msb->req), &len);
+				blk_rq_bytes(req), &len);
 		else
 			error = msb_do_write_request(msb, lba, page, sg,
-				blk_rq_bytes(msb->req), &len);
+				blk_rq_bytes(req), &len);
 
-		spin_lock_irqsave(&msb->q_lock, flags);
-
-		if (len)
-			if (!__blk_end_request(msb->req, BLK_STS_OK, len))
-				msb->req = NULL;
+		if (len && !blk_update_request(req, BLK_STS_OK, len)) {
+			__blk_mq_end_request(req, BLK_STS_OK);
+			spin_lock_irq(&msb->q_lock);
+			msb->req = NULL;
+			spin_unlock_irq(&msb->q_lock);
+		}
 
 		if (error && msb->req) {
 			blk_status_t ret = errno_to_blk_status(error);
+
 			dbg_verbose("IO: ending one sector of the request with error");
-			if (!__blk_end_request(msb->req, ret, msb->page_size))
-				msb->req = NULL;
+			blk_mq_end_request(req, ret);
+			spin_lock_irq(&msb->q_lock);
+			msb->req = NULL;
+			spin_unlock_irq(&msb->q_lock);
 		}
 
 		if (msb->req)
 			dbg_verbose("IO: request still pending");
-
-		spin_unlock_irqrestore(&msb->q_lock, flags);
 	}
 }
 

@@ -2002,29 +1998,40 @@ static int msb_bd_getgeo(struct block_device *bdev,
 	return 0;
 }
 
-static void msb_submit_req(struct request_queue *q)
+static blk_status_t msb_queue_rq(struct blk_mq_hw_ctx *hctx,
+				 const struct blk_mq_queue_data *bd)
 {
-	struct memstick_dev *card = q->queuedata;
+	struct memstick_dev *card = hctx->queue->queuedata;
 	struct msb_data *msb = memstick_get_drvdata(card);
-	struct request *req = NULL;
+	struct request *req = bd->rq;
 
 	dbg_verbose("Submit request");
 
+	spin_lock_irq(&msb->q_lock);
+
 	if (msb->card_dead) {
 		dbg("Refusing requests on removed card");
 
 		WARN_ON(!msb->io_queue_stopped);
 
-		while ((req = blk_fetch_request(q)) != NULL)
-			__blk_end_request_all(req, BLK_STS_IOERR);
-		return;
+		spin_unlock_irq(&msb->q_lock);
+		blk_mq_start_request(req);
+		return BLK_STS_IOERR;
 	}
 
-	if (msb->req)
-		return;
+	if (msb->req) {
+		spin_unlock_irq(&msb->q_lock);
+		return BLK_STS_DEV_RESOURCE;
+	}
+
+	blk_mq_start_request(req);
+	msb->req = req;
 
 	if (!msb->io_queue_stopped)
 		queue_work(msb->io_queue, &msb->io_work);
+
+	spin_unlock_irq(&msb->q_lock);
+	return BLK_STS_OK;
 }
 
 static int msb_check_card(struct memstick_dev *card)

@@ -2040,21 +2047,20 @@ static void msb_stop(struct memstick_dev *card)
 
 	dbg("Stopping all msblock IO");
 
+	blk_mq_stop_hw_queues(msb->queue);
 	spin_lock_irqsave(&msb->q_lock, flags);
-	blk_stop_queue(msb->queue);
 	msb->io_queue_stopped = true;
 	spin_unlock_irqrestore(&msb->q_lock, flags);
 
 	del_timer_sync(&msb->cache_flush_timer);
 	flush_workqueue(msb->io_queue);
 
+	spin_lock_irqsave(&msb->q_lock, flags);
 	if (msb->req) {
-		spin_lock_irqsave(&msb->q_lock, flags);
-		blk_requeue_request(msb->queue, msb->req);
+		blk_mq_requeue_request(msb->req, false);
 		msb->req = NULL;
-		spin_unlock_irqrestore(&msb->q_lock, flags);
 	}
-
+	spin_unlock_irqrestore(&msb->q_lock, flags);
 }
 
 static void msb_start(struct memstick_dev *card)

@@ -2077,9 +2083,7 @@ static void msb_start(struct memstick_dev *card)
 	msb->need_flush_cache = true;
 	msb->io_queue_stopped = false;
 
-	spin_lock_irqsave(&msb->q_lock, flags);
-	blk_start_queue(msb->queue);
-	spin_unlock_irqrestore(&msb->q_lock, flags);
+	blk_mq_start_hw_queues(msb->queue);
 
 	queue_work(msb->io_queue, &msb->io_work);
 

@@ -2092,10 +2096,15 @@ static const struct block_device_operations msb_bdops = {
 	.owner   = THIS_MODULE
 };
 
+static const struct blk_mq_ops msb_mq_ops = {
+	.queue_rq	= msb_queue_rq,
+};
+
 /* Registers the block device */
 static int msb_init_disk(struct memstick_dev *card)
 {
 	struct msb_data *msb = memstick_get_drvdata(card);
+	struct blk_mq_tag_set *set = NULL;
 	int rc;
 	unsigned long capacity;
 

@@ -2112,10 +2121,21 @@ static int msb_init_disk(struct memstick_dev *card)
 		goto out_release_id;
 	}
 
-	msb->queue = blk_init_queue(msb_submit_req, &msb->q_lock);
-	if (!msb->queue) {
-		rc = -ENOMEM;
+	set = &msb->tag_set;
+	set->ops = &msb_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 2;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE;
+	rc = blk_mq_alloc_tag_set(set);
+	if (rc)
 		goto out_put_disk;
+
+	msb->queue = blk_mq_init_queue(set);
+	if (IS_ERR(msb->queue)) {
+		rc = PTR_ERR(msb->queue);
+		msb->queue = NULL;
+		goto out_put_tag;
 	}
 
 	msb->queue->queuedata = card;

@@ -2150,6 +2170,8 @@ static int msb_init_disk(struct memstick_dev *card)
 	dbg("Disk added");
 	return 0;
 
+out_put_tag:
+	blk_mq_free_tag_set(&msb->tag_set);
 out_put_disk:
 	put_disk(msb->disk);
 out_release_id:

@@ -2202,11 +2224,12 @@ static void msb_remove(struct memstick_dev *card)
 	/* Take care of unhandled + new requests from now on */
 	spin_lock_irqsave(&msb->q_lock, flags);
 	msb->card_dead = true;
-	blk_start_queue(msb->queue);
 	spin_unlock_irqrestore(&msb->q_lock, flags);
+	blk_mq_start_hw_queues(msb->queue);
 
 	/* Remove the disk */
 	del_gendisk(msb->disk);
+	blk_mq_free_tag_set(msb->queue->tag_set);
 	blk_cleanup_queue(msb->queue);
 	msb->queue = NULL;
 

index 53962c3b21df..9ba84e0ced63 100644
@@ -152,6 +152,7 @@ struct msb_data {
 	struct gendisk			*disk;
 	struct request_queue		*queue;
 	spinlock_t			q_lock;
+	struct blk_mq_tag_set		tag_set;
 	struct hd_geometry		geometry;
 	struct attribute_group		attr_group;
 	struct request			*req;

index 5ee932631fae..d55b398d16c4 100644
@@ -12,7 +12,7 @@
  *
  */
 
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/idr.h>
 #include <linux/hdreg.h>
 #include <linux/kthread.h>

@@ -142,6 +142,7 @@ struct mspro_block_data {
 	struct gendisk        *disk;
 	struct request_queue  *queue;
 	struct request        *block_req;
+	struct blk_mq_tag_set tag_set;
 	spinlock_t            q_lock;
 
 	unsigned short        page_size;

@@ -152,7 +153,6 @@ struct mspro_block_data {
 	unsigned char         system;
 	unsigned char         read_only:1,
 			      eject:1,
-			      has_request:1,
 			      data_dir:1,
 			      active:1;
 	unsigned char         transfer_cmd;

@@ -694,13 +694,12 @@ static void h_mspro_block_setup_cmd(struct memstick_dev *card, u64 offset,
 
 /*** Data transfer ***/
 
-static int mspro_block_issue_req(struct memstick_dev *card, int chunk)
+static int mspro_block_issue_req(struct memstick_dev *card, bool chunk)
 {
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
 	u64 t_off;
 	unsigned int count;
 
-try_again:
 	while (chunk) {
 		msb->current_page = 0;
 		msb->current_seg = 0;

@@ -709,9 +708,17 @@ static int mspro_block_issue_req(struct memstick_dev *card, int chunk)
 					       msb->req_sg);
 
 		if (!msb->seg_count) {
-			chunk = __blk_end_request_cur(msb->block_req,
-					BLK_STS_RESOURCE);
-			continue;
+			unsigned int bytes = blk_rq_cur_bytes(msb->block_req);
+
+			chunk = blk_update_request(msb->block_req,
+							BLK_STS_RESOURCE,
+							bytes);
+			if (chunk)
+				continue;
+			__blk_mq_end_request(msb->block_req,
+						BLK_STS_RESOURCE);
+			msb->block_req = NULL;
+			break;
 		}
 
 		t_off = blk_rq_pos(msb->block_req);

@@ -729,30 +736,22 @@ static int mspro_block_issue_req(struct memstick_dev *card, int chunk)
 		return 0;
 	}
 
-	dev_dbg(&card->dev, "blk_fetch\n");
-	msb->block_req = blk_fetch_request(msb->queue);
-	if (!msb->block_req) {
-		dev_dbg(&card->dev, "issue end\n");
-		return -EAGAIN;
-	}
-
-	dev_dbg(&card->dev, "trying again\n");
-	chunk = 1;
-	goto try_again;
+	return 1;
 }
 
 static int mspro_block_complete_req(struct memstick_dev *card, int error)
 {
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
-	int chunk, cnt;
+	int cnt;
+	bool chunk;
 	unsigned int t_len = 0;
 	unsigned long flags;
 
 	spin_lock_irqsave(&msb->q_lock, flags);
-	dev_dbg(&card->dev, "complete %d, %d\n", msb->has_request ? 1 : 0,
+	dev_dbg(&card->dev, "complete %d, %d\n", msb->block_req ? 1 : 0,
 		error);
 
-	if (msb->has_request) {
+	if (msb->block_req) {
 		/* Nothing to do - not really an error */
 		if (error == -EAGAIN)
 			error = 0;

@@ -777,15 +776,17 @@ static int mspro_block_complete_req(struct memstick_dev *card, int error)
 		if (error && !t_len)
 			t_len = blk_rq_cur_bytes(msb->block_req);
 
-		chunk = __blk_end_request(msb->block_req,
+		chunk = blk_update_request(msb->block_req,
 				errno_to_blk_status(error), t_len);
-
-		error = mspro_block_issue_req(card, chunk);
-
-		if (!error)
-			goto out;
-		else
-			msb->has_request = 0;
+		if (chunk) {
+			error = mspro_block_issue_req(card, chunk);
+			if (!error)
+				goto out;
+		} else {
+			__blk_mq_end_request(msb->block_req,
+						errno_to_blk_status(error));
+			msb->block_req = NULL;
+		}
 	} else {
 		if (!error)
 			error = -EAGAIN;

@@ -806,8 +807,8 @@ static void mspro_block_stop(struct memstick_dev *card)
 
 	while (1) {
 		spin_lock_irqsave(&msb->q_lock, flags);
-		if (!msb->has_request) {
-			blk_stop_queue(msb->queue);
+		if (!msb->block_req) {
+			blk_mq_stop_hw_queues(msb->queue);
 			rc = 1;
 		}
 		spin_unlock_irqrestore(&msb->q_lock, flags);

@@ -822,32 +823,37 @@ static void mspro_block_stop(struct memstick_dev *card)
 static void mspro_block_start(struct memstick_dev *card)
 {
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
-	unsigned long flags;
 
-	spin_lock_irqsave(&msb->q_lock, flags);
-	blk_start_queue(msb->queue);
-	spin_unlock_irqrestore(&msb->q_lock, flags);
+	blk_mq_start_hw_queues(msb->queue);
 }
 
-static void mspro_block_submit_req(struct request_queue *q)
+static blk_status_t mspro_queue_rq(struct blk_mq_hw_ctx *hctx,
+				   const struct blk_mq_queue_data *bd)
 {
-	struct memstick_dev *card = q->queuedata;
+	struct memstick_dev *card = hctx->queue->queuedata;
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
-	struct request *req = NULL;
 
-	if (msb->has_request)
-		return;
+	spin_lock_irq(&msb->q_lock);
 
-	if (msb->eject) {
-		while ((req = blk_fetch_request(q)) != NULL)
-			__blk_end_request_all(req, BLK_STS_IOERR);
+	if (msb->block_req) {
+		spin_unlock_irq(&msb->q_lock);
+		return BLK_STS_DEV_RESOURCE;
+	}
 
-		return;
+	if (msb->eject) {
+		spin_unlock_irq(&msb->q_lock);
+		blk_mq_start_request(bd->rq);
+		return BLK_STS_IOERR;
 	}
 
-	msb->has_request = 1;
-	if (mspro_block_issue_req(card, 0))
-		msb->has_request = 0;
+	msb->block_req = bd->rq;
+	blk_mq_start_request(bd->rq);
+
+	if (mspro_block_issue_req(card, true))
+		msb->block_req = NULL;
+
+	spin_unlock_irq(&msb->q_lock);
+	return BLK_STS_OK;
 }
 
 /*** Initialization ***/

@@ -1167,12 +1173,17 @@ static int mspro_block_init_card(struct memstick_dev *card)
 
 }
 
+static const struct blk_mq_ops mspro_mq_ops = {
+	.queue_rq	= mspro_queue_rq,
+};
+
 static int mspro_block_init_disk(struct memstick_dev *card)
 {
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
 	struct mspro_devinfo *dev_info = NULL;
 	struct mspro_sys_info *sys_info = NULL;
 	struct mspro_sys_attr *s_attr = NULL;
+	struct blk_mq_tag_set *set;
 	int rc, disk_id;
 	unsigned long capacity;
 

@@ -1206,10 +1217,21 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 		goto out_release_id;
 	}
 
-	msb->queue = blk_init_queue(mspro_block_submit_req, &msb->q_lock);
-	if (!msb->queue) {
-		rc = -ENOMEM;
+	set = &msb->tag_set;
+	set->ops = &mspro_mq_ops;
+	set->nr_hw_queues = 1;
+	set->queue_depth = 2;
+	set->numa_node = NUMA_NO_NODE;
+	set->flags = BLK_MQ_F_SHOULD_MERGE;
+	rc = blk_mq_alloc_tag_set(set);
+	if (rc)
 		goto out_put_disk;
+
+	msb->queue = blk_mq_init_queue(set);
+	if (IS_ERR(msb->queue)) {
+		rc = PTR_ERR(msb->queue);
+		msb->queue = NULL;
+		goto out_put_tag;
 	}
 
 	msb->queue->queuedata = card;

@@ -1240,6 +1262,8 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 	msb->active = 1;
 	return 0;
 
+out_put_tag:
+	blk_mq_free_tag_set(&msb->tag_set);
 out_put_disk:
 	put_disk(msb->disk);
 out_release_id:

@@ -1318,12 +1342,13 @@ static void mspro_block_remove(struct memstick_dev *card)
 
 	spin_lock_irqsave(&msb->q_lock, flags);
 	msb->eject = 1;
-	blk_start_queue(msb->queue);
 	spin_unlock_irqrestore(&msb->q_lock, flags);
+	blk_mq_start_hw_queues(msb->queue);
 
 	del_gendisk(msb->disk);
 	dev_dbg(&card->dev, "mspro block remove\n");
 
+	blk_mq_free_tag_set(msb->queue->tag_set);
 	blk_cleanup_queue(msb->queue);
 	msb->queue = NULL;
 

@@ -1344,8 +1369,9 @@ static int mspro_block_suspend(struct memstick_dev *card, pm_message_t state)
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
 	unsigned long flags;
 
+	blk_mq_stop_hw_queues(msb->queue);
+
 	spin_lock_irqsave(&msb->q_lock, flags);
-	blk_stop_queue(msb->queue);
 	msb->active = 0;
 	spin_unlock_irqrestore(&msb->q_lock, flags);
 

@@ -1355,7 +1381,6 @@ static int mspro_block_suspend(struct memstick_dev *card, pm_message_t state)
 static int mspro_block_resume(struct memstick_dev *card)
 {
 	struct mspro_block_data *msb = memstick_get_drvdata(card);
-	unsigned long flags;
 	int rc = 0;
 
 #ifdef CONFIG_MEMSTICK_UNSAFE_RESUME

@@ -1401,9 +1426,7 @@ static int mspro_block_resume(struct memstick_dev *card)
 
 #endif /* CONFIG_MEMSTICK_UNSAFE_RESUME */
 
-	spin_lock_irqsave(&msb->q_lock, flags);
-	blk_start_queue(msb->queue);
-	spin_unlock_irqrestore(&msb->q_lock, flags);
+	blk_mq_start_hw_queues(msb->queue);
 	return rc;
 }
 

index ae3a7537cf0f..41b57d9c4424 100644
@@ -31,12 +31,11 @@
 #include <linux/cdrom.h>
 #include <linux/genhd.h>
 #include <linux/bio.h>
-#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
 #include <linux/interrupt.h>
 #include <linux/device.h>
 #include <linux/mutex.h>
 #include <linux/wait.h>
-#include <linux/workqueue.h>
 #include <linux/platform_device.h>
 #include <scsi/scsi.h>
 #include <asm/io.h>

@@ -102,11 +101,6 @@ static int gdrom_major;
 static DECLARE_WAIT_QUEUE_HEAD(command_queue);
 static DECLARE_WAIT_QUEUE_HEAD(request_queue);
 
-static DEFINE_SPINLOCK(gdrom_lock);
-static void gdrom_readdisk_dma(struct work_struct *work);
-static DECLARE_WORK(work, gdrom_readdisk_dma);
-static LIST_HEAD(gdrom_deferred);
-
 struct gdromtoc {
 	unsigned int entry[99];
 	unsigned int first, last;

@@ -122,6 +116,7 @@ static struct gdrom_unit {
 	char disk_type;
 	struct gdromtoc *toc;
 	struct request_queue *gdrom_rq;
+	struct blk_mq_tag_set tag_set;
 } gd;
 
 struct gdrom_id {

@@ -584,103 +579,83 @@ static int gdrom_set_interrupt_handlers(void)
  * 9 -> sectors >> 8
  * 10 -> sectors
  */
-static void gdrom_readdisk_dma(struct work_struct *work)
+static blk_status_t gdrom_readdisk_dma(struct request *req)
 {
 	int block, block_cnt;
 	blk_status_t err;
 	struct packet_command *read_command;
-	struct list_head *elem, *next;
-	struct request *req;
 	unsigned long timeout;
 
-	if (list_empty(&gdrom_deferred))
-		return;
 	read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 	if (!read_command)
-		return; /* get more memory later? */
+		return BLK_STS_RESOURCE;
+
 	read_command->cmd[0] = 0x30;
 	read_command->cmd[1] = 0x20;
-	spin_lock(&gdrom_lock);
-	list_for_each_safe(elem, next, &gdrom_deferred) {
-		req = list_entry(elem, struct request, queuelist);
-		spin_unlock(&gdrom_lock);
-		block = blk_rq_pos(req)/GD_TO_BLK + GD_SESSION_OFFSET;
-		block_cnt = blk_rq_sectors(req)/GD_TO_BLK;
-		__raw_writel(virt_to_phys(bio_data(req->bio)), GDROM_DMA_STARTADDR_REG);
-		__raw_writel(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);
-		__raw_writel(1, GDROM_DMA_DIRECTION_REG);
-		__raw_writel(1, GDROM_DMA_ENABLE_REG);
-		read_command->cmd[2] = (block >> 16) & 0xFF;
-		read_command->cmd[3] = (block >> 8) & 0xFF;
-		read_command->cmd[4] = block & 0xFF;
-		read_command->cmd[8] = (block_cnt >> 16) & 0xFF;
-		read_command->cmd[9] = (block_cnt >> 8) & 0xFF;
-		read_command->cmd[10] = block_cnt & 0xFF;
-		/* set for DMA */
-		__raw_writeb(1, GDROM_ERROR_REG);
-		/* other registers */
-		__raw_writeb(0, GDROM_SECNUM_REG);
-		__raw_writeb(0, GDROM_BCL_REG);
-		__raw_writeb(0, GDROM_BCH_REG);
-		__raw_writeb(0, GDROM_DSEL_REG);
-		__raw_writeb(0, GDROM_INTSEC_REG);
-		/* Wait for registers to reset after any previous activity */
-		timeout = jiffies + HZ / 2;
-		while (gdrom_is_busy() && time_before(jiffies, timeout))
-			cpu_relax();
-		__raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
-		timeout = jiffies + HZ / 2;
-		/* Wait for packet command to finish */
-		while (gdrom_is_busy() && time_before(jiffies, timeout))
-			cpu_relax();
-		gd.pending = 1;
-		gd.transfer = 1;
-		outsw(GDROM_DATA_REG, &read_command->cmd, 6);
-		timeout = jiffies + HZ / 2;
-		/* Wait for any pending DMA to finish */
-		while (__raw_readb(GDROM_DMA_STATUS_REG) &&
-			time_before(jiffies, timeout))
-			cpu_relax();
-		/* start transfer */
-		__raw_writeb(1, GDROM_DMA_STATUS_REG);
-		wait_event_interruptible_timeout(request_queue,
-			gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
-		err = gd.transfer ? BLK_STS_IOERR : BLK_STS_OK;
-		gd.transfer = 0;
-		gd.pending = 0;
-		/* now seek to take the request spinlock
-		* before handling ending the request */
-		spin_lock(&gdrom_lock);
-		list_del_init(&req->queuelist);
-		__blk_end_request_all(req, err);
-	}
-	spin_unlock(&gdrom_lock);
+	block = blk_rq_pos(req)/GD_TO_BLK + GD_SESSION_OFFSET;
+	block_cnt = blk_rq_sectors(req)/GD_TO_BLK;
+	__raw_writel(virt_to_phys(bio_data(req->bio)), GDROM_DMA_STARTADDR_REG);
+	__raw_writel(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);
+	__raw_writel(1, GDROM_DMA_DIRECTION_REG);
+	__raw_writel(1, GDROM_DMA_ENABLE_REG);
+	read_command->cmd[2] = (block >> 16) & 0xFF;
+	read_command->cmd[3] = (block >> 8) & 0xFF;
+	read_command->cmd[4] = block & 0xFF;
+	read_command->cmd[8] = (block_cnt >> 16) & 0xFF;
+	read_command->cmd[9] = (block_cnt >> 8) & 0xFF;
+	read_command->cmd[10] = block_cnt & 0xFF;
+	/* set for DMA */
+	__raw_writeb(1, GDROM_ERROR_REG);
+	/* other registers */
+	__raw_writeb(0, GDROM_SECNUM_REG);
+	__raw_writeb(0, GDROM_BCL_REG);
+	__raw_writeb(0, GDROM_BCH_REG);
+	__raw_writeb(0, GDROM_DSEL_REG);
+	__raw_writeb(0, GDROM_INTSEC_REG);
+	/* Wait for registers to reset after any previous activity */
+	timeout = jiffies + HZ / 2;
+	while (gdrom_is_busy() && time_before(jiffies, timeout))
+		cpu_relax();
+	__raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
+	timeout = jiffies + HZ / 2;
+	/* Wait for packet command to finish */
+	while (gdrom_is_busy() && time_before(jiffies, timeout))
+		cpu_relax();
+	gd.pending = 1;
+	gd.transfer = 1;
+	outsw(GDROM_DATA_REG, &read_command->cmd, 6);
+	timeout = jiffies + HZ / 2;
+	/* Wait for any pending DMA to finish */
+	while (__raw_readb(GDROM_DMA_STATUS_REG) &&
+		time_before(jiffies, timeout))
+		cpu_relax();
+	/* start transfer */
+	__raw_writeb(1, GDROM_DMA_STATUS_REG);
+	wait_event_interruptible_timeout(request_queue,
+		gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
+	err = gd.transfer ? BLK_STS_IOERR : BLK_STS_OK;
+	gd.transfer = 0;
+	gd.pending = 0;
+
+	blk_mq_end_request(req, err);
 	kfree(read_command);
+	return BLK_STS_OK;
 }
 
-static void gdrom_request(struct request_queue *rq)
-{
-	struct request *req;
-
-	while ((req = blk_fetch_request(rq)) != NULL) {
-		switch (req_op(req)) {
-		case REQ_OP_READ:
-			/*
-			 * Add to list of deferred work and then schedule
-			 * workqueue.
-			 */
-			list_add_tail(&req->queuelist, &gdrom_deferred);
-			schedule_work(&work);
-			break;
-		case REQ_OP_WRITE:
-			pr_notice("Read only device - write request ignored\n");
-			__blk_end_request_all(req, BLK_STS_IOERR);
-			break;
-		default:
-			printk(KERN_DEBUG "gdrom: Non-fs request ignored\n");
-			__blk_end_request_all(req, BLK_STS_IOERR);
-			break;
-		}
+static blk_status_t gdrom_queue_rq(struct blk_mq_hw_ctx *hctx,
+				   const struct blk_mq_queue_data *bd)
+{
+	blk_mq_start_request(bd->rq);
+
+	switch (req_op(bd->rq)) {
+	case REQ_OP_READ:
+		return gdrom_readdisk_dma(bd->rq);
+	case REQ_OP_WRITE:
+		pr_notice("Read only device - write request ignored\n");
+		return BLK_STS_IOERR;
+	default:
+		printk(KERN_DEBUG "gdrom: Non-fs request ignored\n");
+		return BLK_STS_IOERR;
 	}
 }