[Qemu-devel] [PATCH 2/2] Add serial number support for virtio_blk, V3

[john cooper]

--
address@hidden

 drivers/block/virtio_blk.c |   32 +++++++++++++++++++++++++++++---
 include/linux/virtio_blk.h |    6 ++++++
 2 files changed, 35 insertions(+), 3 deletions(-)
=================================================================
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -146,12 +146,37 @@ static void do_virtblk_request(struct re
                vblk->vq->vq_ops->kick(vblk->vq);
 }
 
+/* return serial# in IDE identify data (all other fields are currently zero)
+ */
+static int virtblk_identity(struct block_device *bdev, void *buf)
+{
+       struct virtio_blk *vblk = bdev->bd_disk->private_data;
+       u16 *id;
+       int rv;
+
+       if (!(id = kzalloc(ATA_ID_WORDS, GFP_KERNEL)))
+               rv = -ENOMEM;
+       else if ((rv = virtio_config_buf(vblk->vdev, VIRTIO_BLK_F_SN,
+               offsetof(struct virtio_blk_config, serial), &id[ATA_ID_SERNO],
+               ATA_ID_SERNO_LEN)))
+                       ;
+       else if (copy_to_user(buf, id, ATA_ID_WORDS))
+               rv = -EFAULT;
+       else
+               rv = 0;
+       if (id)
+               kfree(id);
+        return (rv);
+}
+
 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);
+       if (cmd == HDIO_GET_IDENTITY)
+               return (virtblk_identity(bdev, (void __user *)data));
+       else
+               return scsi_cmd_ioctl(bdev->bd_disk->queue, bdev->bd_disk,
+                       mode, cmd, (void __user *)data);
 }
 
 /* We provide getgeo only to please some old bootloader/partitioning tools */
@@ -356,6 +381,7 @@ 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_SN
 };
 
 static struct virtio_driver virtio_blk = {
=================================================================
--- a/include/linux/virtio_blk.h
+++ b/include/linux/virtio_blk.h
@@ -15,7 +15,12 @@
 #define VIRTIO_BLK_F_GEOMETRY  4       /* Legacy geometry available  */
 #define VIRTIO_BLK_F_RO                5       /* Disk is read-only */
 #define VIRTIO_BLK_F_BLK_SIZE  6       /* Block size of disk is available*/
+#define VIRTIO_BLK_F_SN                8       /* serial number supported */
 
+#define BLOCK_SERIAL_STRLEN    20
+
+/* mapped into pci i/o region 0
+ */
 struct virtio_blk_config
 {
        /* The capacity (in 512-byte sectors). */
@@ -32,6 +37,7 @@ struct virtio_blk_config
        } geometry;
        /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
        __u32 blk_size;
+       __u8 serial[BLOCK_SERIAL_STRLEN];
 } __attribute__((packed));
 
 /* These two define direction. */