virtio_blk: comment fix

update virtio blk header from latest linux, include comment fixups.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Message-id: 1428854036-12806-1-git-send-email-mst@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

include/standard-headers/linux/virtio_blk.h

@@ -58,7 +58,7 @@ struct virtio_blk_config {
 	uint32_t size_max;
 	/* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
 	uint32_t seg_max;
-	/* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
+	/* geometry of the device (if VIRTIO_BLK_F_GEOMETRY) */
 	struct virtio_blk_geometry {
 		uint16_t cylinders;
 		uint8_t heads;
@@ -117,7 +117,11 @@ struct virtio_blk_config {
 #define VIRTIO_BLK_T_BARRIER	0x80000000
 #endif /* !VIRTIO_BLK_NO_LEGACY */
 
-/* This is the first element of the read scatter-gather list. */
+/*
+ * This comes first in the read scatter-gather list.
+ * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated,
+ * this is the first element of the read scatter-gather list.
+ */
 struct virtio_blk_outhdr {
 	/* VIRTIO_BLK_T* */
 	__virtio32 type;