xref: /freebsd/sys/dev/virtio/balloon/virtio_balloon.h (revision 3f0164abf32b9b761e0a2cb4bdca3a8b84f156d4)
1 /*-
2  * This header is BSD licensed so anyone can use the definitions to implement
3  * compatible drivers/servers.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of IBM nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #ifndef _VIRTIO_BALLOON_H
32 #define _VIRTIO_BALLOON_H
33 
34 /* Feature bits. */
35 #define VIRTIO_BALLOON_F_MUST_TELL_HOST	0x1 /* Tell before reclaiming pages */
36 #define VIRTIO_BALLOON_F_STATS_VQ	0x2 /* Memory stats virtqueue */
37 
38 /* Size of a PFN in the balloon interface. */
39 #define VIRTIO_BALLOON_PFN_SHIFT 12
40 
41 struct virtio_balloon_config {
42 	/* Number of pages host wants Guest to give up. */
43 	uint32_t num_pages;
44 
45 	/* Number of pages we've actually got in balloon. */
46 	uint32_t actual;
47 };
48 
49 #define VIRTIO_BALLOON_S_SWAP_IN  0   /* Amount of memory swapped in */
50 #define VIRTIO_BALLOON_S_SWAP_OUT 1   /* Amount of memory swapped out */
51 #define VIRTIO_BALLOON_S_MAJFLT   2   /* Number of major faults */
52 #define VIRTIO_BALLOON_S_MINFLT   3   /* Number of minor faults */
53 #define VIRTIO_BALLOON_S_MEMFREE  4   /* Total amount of free memory */
54 #define VIRTIO_BALLOON_S_MEMTOT   5   /* Total amount of memory */
55 #define VIRTIO_BALLOON_S_NR       6
56 
57 struct virtio_balloon_stat {
58 	uint16_t tag;
59 	uint64_t val;
60 } __packed;
61 
62 #endif /* _VIRTIO_BALLOON_H */
63