[Qemu-devel] [PATCH 1/4] Add virtio disk identification support

[john cooper <john.cooper@redhat.com>]

Add virtio-blk device id (s/n) support via virtio request.
Remove artifacts of pci and ATA_IDENTIFY implementation
relative to prior versions.

Signed-off-by: john cooper <john.cooper@redhat.com>
---

diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c
index 9915840..358b0af 100644
--- a/hw/virtio-blk.c
+++ b/hw/virtio-blk.c
@@ -19,6 +19,8 @@
 # include <scsi/sg.h>
 #endif
 
+#define min(a,b) ((a) < (b) ? (a) : (b))
+
 typedef struct VirtIOBlock
 {
     VirtIODevice vdev;
@@ -28,6 +30,7 @@ typedef struct VirtIOBlock
     QEMUBH *bh;
     BlockConf *conf;
     unsigned short sector_mask;
+    char sn[BLOCK_SERIAL_STRLEN];
 } VirtIOBlock;
 
 static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev)
@@ -317,6 +320,12 @@ static void virtio_blk_handle_request(VirtIOBlockReq *req,
         virtio_blk_handle_flush(req);
     } 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);
@@ -496,6 +505,8 @@ VirtIODevice *virtio_blk_init(DeviceState *dev, BlockConf *conf)
     bdrv_guess_geometry(s->bs, &cylinders, &heads, &secs);
     bdrv_set_geometry_hint(s->bs, cylinders, heads, secs);
 
+    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);
diff --git a/hw/virtio-blk.h b/hw/virtio-blk.h
index 7a7ece3..fff46da 100644
--- a/hw/virtio-blk.h
+++ b/hw/virtio-blk.h
@@ -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

-- 
john.cooper@redhat.com