Merge branch 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux...

[sfrench/cifs-2.6.git] / drivers / block / virtio_blk.c

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 2138a7ae050c10c44bdba1608f441a7811ca1a22..258bc2ae2885625a1650cebcabb4b9eb975092bb 100644 (file)
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -50,7 +50,7 @@ static void blk_done(struct virtqueue *vq)
        unsigned long flags;
 
        spin_lock_irqsave(&vblk->lock, flags);
-       while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
+       while ((vbr = virtqueue_get_buf(vblk->vq, &len)) != NULL) {
                int error;
 
                switch (vbr->status) {
@@ -70,6 +70,8 @@ static void blk_done(struct virtqueue *vq)
                        vbr->req->sense_len = vbr->in_hdr.sense_len;
                        vbr->req->errors = vbr->in_hdr.errors;
                }
+               if (blk_special_request(vbr->req))
+                       vbr->req->errors = (error != 0);
 
                __blk_end_request_all(vbr->req, error);
                list_del(&vbr->list);
@@ -103,6 +105,11 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
                vbr->out_hdr.sector = 0;
                vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
                break;
+       case REQ_TYPE_SPECIAL:
+               vbr->out_hdr.type = VIRTIO_BLK_T_GET_ID;
+               vbr->out_hdr.sector = 0;
+               vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
+               break;
        case REQ_TYPE_LINUX_BLOCK:
                if (req->cmd[0] == REQ_LB_OP_FLUSH) {
                        vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
@@ -151,7 +158,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
                }
        }
 
-       if (vblk->vq->vq_ops->add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) {
+       if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) {
                mempool_free(vbr, vblk->pool);
                return false;
        }
@@ -180,7 +187,7 @@ static void do_virtblk_request(struct request_queue *q)
        }
 
        if (issued)
-               vblk->vq->vq_ops->kick(vblk->vq);
+               virtqueue_kick(vblk->vq);
 }
 
 static void virtblk_prepare_flush(struct request_queue *q, struct request *req)
@@ -189,12 +196,45 @@ static void virtblk_prepare_flush(struct request_queue *q, struct request *req)
        req->cmd[0] = REQ_LB_OP_FLUSH;
 }
 
+/* return id (s/n) string for *disk to *id_str
+ */
+static int virtblk_get_id(struct gendisk *disk, char *id_str)
+{
+       struct virtio_blk *vblk = disk->private_data;
+       struct request *req;
+       struct bio *bio;
+
+       bio = bio_map_kern(vblk->disk->queue, id_str, VIRTIO_BLK_ID_BYTES,
+                          GFP_KERNEL);
+       if (IS_ERR(bio))
+               return PTR_ERR(bio);
+
+       req = blk_make_request(vblk->disk->queue, bio, GFP_KERNEL);
+       if (IS_ERR(req)) {
+               bio_put(bio);
+               return PTR_ERR(req);
+       }
+
+       req->cmd_type = REQ_TYPE_SPECIAL;
+       return blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
+}
+
 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
                         unsigned cmd, unsigned long data)
 {
        struct gendisk *disk = bdev->bd_disk;
        struct virtio_blk *vblk = disk->private_data;
 
+       if (cmd == 0x56424944) { /* 'VBID' */
+               void __user *usr_data = (void __user *)data;
+               char id_str[VIRTIO_BLK_ID_BYTES];
+               int err;
+
+               err = virtblk_get_id(disk, id_str);
+               if (!err && copy_to_user(usr_data, id_str, VIRTIO_BLK_ID_BYTES))
+                       err = -EFAULT;
+               return err;
+       }
        /*
         * Only allow the generic SCSI ioctls if the host can support it.
         */
@@ -258,7 +298,9 @@ static int __devinit virtblk_probe(struct virtio_device *vdev)
        err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX,
                                offsetof(struct virtio_blk_config, seg_max),
                                &sg_elems);
-       if (err)
+
+       /* We need at least one SG element, whatever they say. */
+       if (err || !sg_elems)
                sg_elems = 1;
 
        /* We need an extra sg elements at head and tail. */