1 /*
2  * Virtio Support
3  *
4  * Copyright IBM, Corp. 2007-2008
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.ibm.com>
8  *  Rusty Russell     <rusty@rustcorp.com.au>
9  *
10  * This work is licensed under the terms of the GNU GPL, version 2.  See
11  * the COPYING file in the top-level directory.
12  *
13  */
14 
15 #ifndef _QEMU_VIRTIO_BALLOON_H
16 #define _QEMU_VIRTIO_BALLOON_H
17 
18 #include "hw/virtio/virtio.h"
19 #include "hw/pci/pci.h"
20 
21 #define TYPE_VIRTIO_BALLOON "virtio-balloon-device"
22 #define VIRTIO_BALLOON(obj) \
23         OBJECT_CHECK(VirtIOBalloon, (obj), TYPE_VIRTIO_BALLOON)
24 
25 /* from Linux's linux/virtio_balloon.h */
26 
27 /* The ID for virtio_balloon */
28 #define VIRTIO_ID_BALLOON 5
29 
30 /* The feature bitmap for virtio balloon */
31 #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */
32 #define VIRTIO_BALLOON_F_STATS_VQ 1       /* Memory stats virtqueue */
33 
34 /* Size of a PFN in the balloon interface. */
35 #define VIRTIO_BALLOON_PFN_SHIFT 12
36 
37 struct virtio_balloon_config
38 {
39     /* Number of pages host wants Guest to give up. */
40     uint32_t num_pages;
41     /* Number of pages we've actually got in balloon. */
42     uint32_t actual;
43 };
44 
45 /* Memory Statistics */
46 #define VIRTIO_BALLOON_S_SWAP_IN  0   /* Amount of memory swapped in */
47 #define VIRTIO_BALLOON_S_SWAP_OUT 1   /* Amount of memory swapped out */
48 #define VIRTIO_BALLOON_S_MAJFLT   2   /* Number of major faults */
49 #define VIRTIO_BALLOON_S_MINFLT   3   /* Number of minor faults */
50 #define VIRTIO_BALLOON_S_MEMFREE  4   /* Total amount of free memory */
51 #define VIRTIO_BALLOON_S_MEMTOT   5   /* Total amount of memory */
52 #define VIRTIO_BALLOON_S_NR       6
53 
54 typedef struct VirtIOBalloonStat {
55     uint16_t tag;
56     uint64_t val;
57 } QEMU_PACKED VirtIOBalloonStat;
58 
59 typedef struct VirtIOBalloon {
60     VirtIODevice parent_obj;
61     VirtQueue *ivq, *dvq, *svq;
62     uint32_t num_pages;
63     uint32_t actual;
64     uint64_t stats[VIRTIO_BALLOON_S_NR];
65     VirtQueueElement stats_vq_elem;
66     size_t stats_vq_offset;
67     QEMUTimer *stats_timer;
68     int64_t stats_last_update;
69     int64_t stats_poll_interval;
70 } VirtIOBalloon;
71 
72 #endif
73