virtio-balloon: include statistics of disk/file caches

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/virtio/virtio-balloon.c

@@ -50,6 +50,7 @@ static const char *balloon_stat_names[] = {
    [VIRTIO_BALLOON_S_MEMFREE] = "stat-free-memory",
    [VIRTIO_BALLOON_S_MEMTOT] = "stat-total-memory",
    [VIRTIO_BALLOON_S_AVAIL] = "stat-available-memory",
+   [VIRTIO_BALLOON_S_CACHES] = "stat-disk-caches",
    [VIRTIO_BALLOON_S_NR] = NULL
 };
 

include/standard-headers/linux/virtio_balloon.h

@@ -52,7 +52,8 @@ struct virtio_balloon_config {
 #define VIRTIO_BALLOON_S_MEMFREE  4   /* Total amount of free memory */
 #define VIRTIO_BALLOON_S_MEMTOT   5   /* Total amount of memory */
 #define VIRTIO_BALLOON_S_AVAIL    6   /* Available memory as in /proc */
-#define VIRTIO_BALLOON_S_NR       7
+#define VIRTIO_BALLOON_S_CACHES   7   /* Disk caches */
+#define VIRTIO_BALLOON_S_NR       8
 
 /*
  * Memory statistics structure.