#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;
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
struct list_head list;
struct request *req;
struct virtio_blk_outhdr out_hdr;
+ struct virtio_scsi_inhdr in_hdr;
u8 status;
};
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;
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);
}
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);
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;
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)) {
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. */
blk_stop_queue(q);
break;
}
- blkdev_dequeue_request(req);
+ blk_start_request(req);
issued++;
}
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 */
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;
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);
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) {
}
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,
&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;
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 = {