virtio: add virtio IDs file

Virtio IDs are spread all over the tree which makes assigning new IDs
bothersome. Putting them together should make the process less error-prone.

Signed-off-by: Fernando Luis Vazquez Cao <[e-mail]>
Signed-off-by: Rusty Russell <[e-mail]>

Documentation/lguest/lguest.c

···
 #include <signal.h>
 #include "linux/lguest_launcher.h"
 #include "linux/virtio_config.h"
+#include <linux/virtio_ids.h>
 #include "linux/virtio_net.h"
 #include "linux/virtio_blk.h"
 #include "linux/virtio_console.h"

drivers/block/virtio_blk.c

···
 #include <linux/blkdev.h>
 #include <linux/hdreg.h>
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_blk.h>
 #include <linux/scatterlist.h>
 

drivers/char/hw_random/virtio-rng.c

···
 #include <linux/scatterlist.h>
 #include <linux/spinlock.h>
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_rng.h>
 
 /* The host will fill any buffer we give it with sweet, sweet randomness.  We

drivers/char/virtio_console.c

···
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_console.h>
 #include "hvc_console.h"
 

drivers/net/virtio_net.c

···
 #include <linux/ethtool.h>
 #include <linux/module.h>
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_net.h>
 #include <linux/scatterlist.h>
 #include <linux/if_vlan.h>

drivers/virtio/virtio_balloon.c

···
  */
 //#define DEBUG
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_balloon.h>
 #include <linux/swap.h>
 #include <linux/kthread.h>

include/linux/virtio_9p.h

···
  * compatible drivers/servers. */
 #include <linux/virtio_config.h>
 
-/* The ID for virtio console */
-#define VIRTIO_ID_9P	9
 /* Maximum number of virtio channels per partition (1 for now) */
 #define MAX_9P_CHAN	1
 

include/linux/virtio_balloon.h

···
  * compatible drivers/servers. */
 #include <linux/virtio_config.h>
 
-/* The ID for virtio_balloon */
-#define VIRTIO_ID_BALLOON	5
-
 /* The feature bitmap for virtio balloon */
 #define VIRTIO_BALLOON_F_MUST_TELL_HOST	0 /* Tell before reclaiming pages */
 

include/linux/virtio_blk.h

···
 #include <linux/types.h>
 #include <linux/virtio_config.h>
 
-/* The ID for virtio_block */
-#define VIRTIO_ID_BLOCK	2
-
 /* Feature bits */
 #define VIRTIO_BLK_F_BARRIER	0	/* Does host support barriers? */
 #define VIRTIO_BLK_F_SIZE_MAX	1	/* Indicates maximum segment size */

include/linux/virtio_console.h

···
 /* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
  * anyone can use the definitions to implement compatible drivers/servers. */
 
-/* The ID for virtio console */
-#define VIRTIO_ID_CONSOLE	3
-
 /* Feature bits */
 #define VIRTIO_CONSOLE_F_SIZE	0	/* Does host provide console size? */
 

include/linux/virtio_ids.h

···
+#ifndef _LINUX_VIRTIO_IDS_H
+#define _LINUX_VIRTIO_IDS_H
+/*
+ * Virtio IDs
+ *
+ * This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ */
+
+#define VIRTIO_ID_NET		1 /* virtio net */
+#define VIRTIO_ID_BLOCK		2 /* virtio block */
+#define VIRTIO_ID_CONSOLE	3 /* virtio console */
+#define VIRTIO_ID_RNG		4 /* virtio ring */
+#define VIRTIO_ID_BALLOON	5 /* virtio balloon */
+#define VIRTIO_ID_9P		9 /* 9p virtio console */
+
+#endif /* _LINUX_VIRTIO_IDS_H */

include/linux/virtio_net.h

···
 #include <linux/virtio_config.h>
 #include <linux/if_ether.h>
 
-/* The ID for virtio_net */
-#define VIRTIO_ID_NET	1
-
 /* The feature bitmap for virtio net */
 #define VIRTIO_NET_F_CSUM	0	/* Host handles pkts w/ partial csum */
 #define VIRTIO_NET_F_GUEST_CSUM	1	/* Guest handles pkts w/ partial csum */

include/linux/virtio_rng.h

···
  * compatible drivers/servers. */
 #include <linux/virtio_config.h>
 
-/* The ID for virtio_rng */
-#define VIRTIO_ID_RNG	4
-
 #endif /* _LINUX_VIRTIO_RNG_H */

net/9p/trans_virtio.c

···
 #include <net/9p/transport.h>
 #include <linux/scatterlist.h>
 #include <linux/virtio.h>
+#include <linux/virtio_ids.h>
 #include <linux/virtio_9p.h>
 
 #define VIRTQUEUE_NUM	128