@@ -26,6 +26,7 @@ typedef struct VirtIOBlock
QEMUBH *bh;
BlockConf *conf;
unsigned short sector_mask;
+ char sn[BLOCK_SERIAL_STRLEN];
} VirtIOBlock;
static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev)
@@ -324,6 +325,12 @@ static void virtio_blk_handle_request(VirtIOBlockReq *req,
virtio_blk_handle_flush(req, mrb);
} else if (req->out->type & VIRTIO_BLK_T_SCSI_CMD) {
virtio_blk_handle_scsi(req);
+ } else if (req->out->type & VIRTIO_BLK_T_GET_ID) {
+ VirtIOBlock *s = req->dev;
+
+ memcpy(req->elem.in_sg[0].iov_base, s->sn,
+ MIN(req->elem.in_sg[0].iov_len, sizeof(s->sn)));
+ virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
} else if (req->out->type & VIRTIO_BLK_T_OUT) {
qemu_iovec_init_external(&req->qiov, &req->elem.out_sg[1],
req->elem.out_num - 1);
@@ -495,6 +502,12 @@ VirtIODevice *virtio_blk_init(DeviceState *dev, BlockConf *conf)
s->sector_mask = (s->conf->logical_block_size / BDRV_SECTOR_SIZE) - 1;
bdrv_guess_geometry(s->bs, &cylinders, &heads, &secs);
+ /* NB: per existing s/n string convention we really intend to hard-limit
+ * the copy length to sizeof (s->sn) even in the case we're left without
+ * a trailing '\0'
+ */
+ strncpy(s->sn, drive_get_serial(s->bs), sizeof (s->sn));
+
s->vq = virtio_add_queue(&s->vdev, 128, virtio_blk_handle_output);
qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s);
@@ -59,6 +59,9 @@ struct virtio_blk_config
/* Flush the volatile write cache */
#define VIRTIO_BLK_T_FLUSH 4
+/* return the device ID string */
+#define VIRTIO_BLK_T_GET_ID 8
+
/* Barrier before this op. */
#define VIRTIO_BLK_T_BARRIER 0x80000000
This patch adds the final missing bits for support of passing a serial/id string to a virtio-blk guest driver. The guest-side component already exists in the virtio driver, and has recently been reworked by Ryan to export a /sys interface for retrival of the id from guest userland. Signed-off-by: john cooper<john.cooper@redhat.com> ---