X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Fblock%2Fvirtio_blk.c;h=c0facaa55cf46ee96932d08ee453829735bdf939;hb=1d589bb16b825b3a7b4edd34d997f1f1f953033d;hp=85d79a02d48726c150e6f8f1b17889f84bc8cc8d;hpb=ef71b1b87521ff93ed77b3e8f3e149afb392761c;p=mv-sheeva.git

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 85d79a02d48..c0facaa55cf 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -6,7 +6,6 @@
 #include <linux/virtio_blk.h>
 #include <linux/scatterlist.h>
 
-#define VIRTIO_MAX_SG	(3+MAX_PHYS_SEGMENTS)
 #define PART_BITS 4
 
 static int major, index;
@@ -26,8 +25,11 @@ struct virtio_blk
 
 	mempool_t *pool;
 
+	/* What host tells us, plus 2 for header & tailer. */
+	unsigned int sg_elems;
+
 	/* Scatterlist: can be too big for stack. */
-	struct scatterlist sg[VIRTIO_MAX_SG];
+	struct scatterlist sg[/*sg_elems*/];
 };
 
 struct virtblk_req
@@ -35,6 +37,7 @@ struct virtblk_req
 	struct list_head list;
 	struct request *req;
 	struct virtio_blk_outhdr out_hdr;
+	struct virtio_scsi_inhdr in_hdr;
 	u8 status;
 };
 
@@ -48,6 +51,7 @@ static void blk_done(struct virtqueue *vq)
 	spin_lock_irqsave(&vblk->lock, flags);
 	while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
 		int error;
+
 		switch (vbr->status) {
 		case VIRTIO_BLK_S_OK:
 			error = 0;
@@ -60,7 +64,13 @@ static void blk_done(struct virtqueue *vq)
 			break;
 		}
 
-		__blk_end_request(vbr->req, error, blk_rq_bytes(vbr->req));
+		if (blk_pc_request(vbr->req)) {
+			vbr->req->resid_len = vbr->in_hdr.residual;
+			vbr->req->sense_len = vbr->in_hdr.sense_len;
+			vbr->req->errors = vbr->in_hdr.errors;
+		}
+
+		__blk_end_request_all(vbr->req, error);
 		list_del(&vbr->list);
 		mempool_free(vbr, vblk->pool);
 	}
@@ -72,7 +82,7 @@ static void blk_done(struct virtqueue *vq)
 static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 		   struct request *req)
 {
-	unsigned long num, out, in;
+	unsigned long num, out = 0, in = 0;
 	struct virtblk_req *vbr;
 
 	vbr = mempool_alloc(vblk->pool, GFP_ATOMIC);
@@ -83,7 +93,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 	vbr->req = req;
 	if (blk_fs_request(vbr->req)) {
 		vbr->out_hdr.type = 0;
-		vbr->out_hdr.sector = vbr->req->sector;
+		vbr->out_hdr.sector = blk_rq_pos(vbr->req);
 		vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
 	} else if (blk_pc_request(vbr->req)) {
 		vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD;
@@ -97,20 +107,36 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 	if (blk_barrier_rq(vbr->req))
 		vbr->out_hdr.type |= VIRTIO_BLK_T_BARRIER;
 
-	/* This init could be done at vblk creation time */
-	sg_init_table(vblk->sg, VIRTIO_MAX_SG);
-	sg_set_buf(&vblk->sg[0], &vbr->out_hdr, sizeof(vbr->out_hdr));
-	num = blk_rq_map_sg(q, vbr->req, vblk->sg+1);
-	sg_set_buf(&vblk->sg[num+1], &vbr->status, sizeof(vbr->status));
+	sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
 
-	if (rq_data_dir(vbr->req) == WRITE) {
-		vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
-		out = 1 + num;
-		in = 1;
-	} else {
-		vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
-		out = 1;
-		in = 1 + num;
+	/*
+	 * If this is a packet command we need a couple of additional headers.
+	 * Behind the normal outhdr we put a segment with the scsi command
+	 * block, and before the normal inhdr we put the sense data and the
+	 * inhdr with additional status information before the normal inhdr.
+	 */
+	if (blk_pc_request(vbr->req))
+		sg_set_buf(&vblk->sg[out++], vbr->req->cmd, vbr->req->cmd_len);
+
+	num = blk_rq_map_sg(q, vbr->req, vblk->sg + out);
+
+	if (blk_pc_request(vbr->req)) {
+		sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, 96);
+		sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr,
+			   sizeof(vbr->in_hdr));
+	}
+
+	sg_set_buf(&vblk->sg[num + out + in++], &vbr->status,
+		   sizeof(vbr->status));
+
+	if (num) {
+		if (rq_data_dir(vbr->req) == WRITE) {
+			vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
+			out += num;
+		} else {
+			vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
+			in += num;
+		}
 	}
 
 	if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr)) {
@@ -124,13 +150,12 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 
 static void do_virtblk_request(struct request_queue *q)
 {
-	struct virtio_blk *vblk = NULL;
+	struct virtio_blk *vblk = q->queuedata;
 	struct request *req;
 	unsigned int issued = 0;
 
-	while ((req = elv_next_request(q)) != NULL) {
-		vblk = req->rq_disk->private_data;
-		BUG_ON(req->nr_phys_segments > ARRAY_SIZE(vblk->sg));
+	while ((req = blk_peek_request(q)) != NULL) {
+		BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
 
 		/* If this request fails, stop queue and wait for something to
 		   finish to restart it. */
@@ -138,7 +163,7 @@ static void do_virtblk_request(struct request_queue *q)
 			blk_stop_queue(q);
 			break;
 		}
-		blkdev_dequeue_request(req);
+		blk_start_request(req);
 		issued++;
 	}
 
@@ -146,12 +171,51 @@ static void do_virtblk_request(struct request_queue *q)
 		vblk->vq->vq_ops->kick(vblk->vq);
 }
 
+/* return ATA identify data
+ */
+static int virtblk_identify(struct gendisk *disk, void *argp)
+{
+	struct virtio_blk *vblk = disk->private_data;
+	void *opaque;
+	int err = -ENOMEM;
+
+	opaque = kmalloc(VIRTIO_BLK_ID_BYTES, GFP_KERNEL);
+	if (!opaque)
+		goto out;
+
+	err = virtio_config_buf(vblk->vdev, VIRTIO_BLK_F_IDENTIFY,
+		offsetof(struct virtio_blk_config, identify), opaque,
+		VIRTIO_BLK_ID_BYTES);
+
+	if (err)
+		goto out_kfree;
+
+	if (copy_to_user(argp, opaque, VIRTIO_BLK_ID_BYTES))
+		err = -EFAULT;
+
+out_kfree:
+	kfree(opaque);
+out:
+	return err;
+}
+
 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
 			 unsigned cmd, unsigned long data)
 {
-	return scsi_cmd_ioctl(bdev->bd_disk->queue,
-			      bdev->bd_disk, mode, cmd,
-			      (void __user *)data);
+	struct gendisk *disk = bdev->bd_disk;
+	struct virtio_blk *vblk = disk->private_data;
+	void __user *argp = (void __user *)data;
+
+	if (cmd == HDIO_GET_IDENTITY)
+		return virtblk_identify(disk, argp);
+
+	/*
+	 * Only allow the generic SCSI ioctls if the host can support it.
+	 */
+	if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
+		return -ENOIOCTLCMD;
+
+	return scsi_cmd_ioctl(disk->queue, disk, mode, cmd, argp);
 }
 
 /* We provide getgeo only to please some old bootloader/partitioning tools */
@@ -196,12 +260,22 @@ static int virtblk_probe(struct virtio_device *vdev)
 	int err;
 	u64 cap;
 	u32 v;
-	u32 blk_size;
+	u32 blk_size, sg_elems;
 
 	if (index_to_minor(index) >= 1 << MINORBITS)
 		return -ENOSPC;
 
-	vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
+	/* We need to know how many segments before we allocate. */
+	err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX,
+				offsetof(struct virtio_blk_config, seg_max),
+				&sg_elems);
+	if (err)
+		sg_elems = 1;
+
+	/* We need an extra sg elements at head and tail. */
+	sg_elems += 2;
+	vdev->priv = vblk = kmalloc(sizeof(*vblk) +
+				    sizeof(vblk->sg[0]) * sg_elems, GFP_KERNEL);
 	if (!vblk) {
 		err = -ENOMEM;
 		goto out;
@@ -210,6 +284,8 @@ static int virtblk_probe(struct virtio_device *vdev)
 	INIT_LIST_HEAD(&vblk->reqs);
 	spin_lock_init(&vblk->lock);
 	vblk->vdev = vdev;
+	vblk->sg_elems = sg_elems;
+	sg_init_table(vblk->sg, vblk->sg_elems);
 
 	/* We expect one virtqueue, for output. */
 	vblk->vq = vdev->config->find_vq(vdev, 0, blk_done);
@@ -237,6 +313,9 @@ static int virtblk_probe(struct virtio_device *vdev)
 		goto out_put_disk;
 	}
 
+	vblk->disk->queue->queuedata = vblk;
+	queue_flag_set_unlocked(QUEUE_FLAG_VIRT, vblk->disk->queue);
+
 	if (index < 26) {
 		sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26);
 	} else if (index < (26 + 1) * 26) {
@@ -277,6 +356,13 @@ static int virtblk_probe(struct virtio_device *vdev)
 	}
 	set_capacity(vblk->disk, cap);
 
+	/* We can handle whatever the host told us to handle. */
+	blk_queue_max_phys_segments(vblk->disk->queue, vblk->sg_elems-2);
+	blk_queue_max_hw_segments(vblk->disk->queue, vblk->sg_elems-2);
+
+	/* No real sector limit. */
+	blk_queue_max_sectors(vblk->disk->queue, -1U);
+
 	/* Host can optionally specify maximum segment size and number of
 	 * segments. */
 	err = virtio_config_val(vdev, VIRTIO_BLK_F_SIZE_MAX,
@@ -284,19 +370,15 @@ static int virtblk_probe(struct virtio_device *vdev)
 				&v);
 	if (!err)
 		blk_queue_max_segment_size(vblk->disk->queue, v);
-
-	err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX,
-				offsetof(struct virtio_blk_config, seg_max),
-				&v);
-	if (!err)
-		blk_queue_max_hw_segments(vblk->disk->queue, v);
+	else
+		blk_queue_max_segment_size(vblk->disk->queue, -1U);
 
 	/* Host can optionally specify the block size of the device */
 	err = virtio_config_val(vdev, VIRTIO_BLK_F_BLK_SIZE,
 				offsetof(struct virtio_blk_config, blk_size),
 				&blk_size);
 	if (!err)
-		blk_queue_hardsect_size(vblk->disk->queue, blk_size);
+		blk_queue_logical_block_size(vblk->disk->queue, blk_size);
 
 	add_disk(vblk->disk);
 	return 0;
@@ -339,6 +421,7 @@ static struct virtio_device_id id_table[] = {
 static unsigned int features[] = {
 	VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX,
 	VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
+	VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY
 };
 
 static struct virtio_driver virtio_blk = {