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author | Hannes Reinecke <hare@suse.de> | 2009-05-18 12:41:30 (GMT) |
---|---|---|
committer | Jens Axboe <jens.axboe@oracle.com> | 2009-05-18 12:41:30 (GMT) |
commit | 1cde26f928863d90e9e7c1217880c8450464d305 (patch) | |
tree | e0f6e5157cccc8ab8b87b1192a1da6ddc6113e82 /drivers/block | |
parent | 6c3b46f74587d46e71b8c2b78fdca626a3aca280 (diff) | |
download | linux-1cde26f928863d90e9e7c1217880c8450464d305.tar.xz |
virtio_blk: SG_IO passthru support
Add support for SG_IO passthru to virtio_blk. We add the scsi command
block after the normal outhdr, and the scsi inhdr with full status
information aswell as the sense buffer before the regular inhdr.
[hch: forward ported, added the VIRTIO_BLK_F_SCSI flags, some comments
and tested the whole beast]
[axboe: updated to use ->resid and not dual-path the byte count]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ checkpatch.pl tweak)
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/virtio_blk.c | 64 |
1 files changed, 50 insertions, 14 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index dfe9ee5..62275db 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -37,6 +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; }; @@ -49,7 +50,9 @@ 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) { + unsigned int nr_bytes; int error; + switch (vbr->status) { case VIRTIO_BLK_S_OK: error = 0; @@ -62,6 +65,12 @@ static void blk_done(struct virtqueue *vq) break; } + 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); @@ -74,7 +83,7 @@ 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); @@ -99,18 +108,36 @@ 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; - 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)) { @@ -148,8 +175,16 @@ static void do_virtblk_request(struct request_queue *q) 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, + struct gendisk *disk = bdev->bd_disk; + struct virtio_blk *vblk = disk->private_data; + + /* + * 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, (void __user *)data); } @@ -356,6 +391,7 @@ 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, }; static struct virtio_driver virtio_blk = { |