1 | #ifndef _LINUX_VIRTIO_BALLOON_H |
2 | #define _LINUX_VIRTIO_BALLOON_H |
3 | /* This header is BSD licensed so anyone can use the definitions to implement |
4 | * compatible drivers/servers. |
5 | * |
6 | * Redistribution and use in source and binary forms, with or without |
7 | * modification, are permitted provided that the following conditions |
8 | * are met: |
9 | * 1. Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
11 | * 2. Redistributions in binary form must reproduce the above copyright |
12 | * notice, this list of conditions and the following disclaimer in the |
13 | * documentation and/or other materials provided with the distribution. |
14 | * 3. Neither the name of IBM nor the names of its contributors |
15 | * may be used to endorse or promote products derived from this software |
16 | * without specific prior written permission. |
17 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND |
18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
20 | * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE |
21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
27 | * SUCH DAMAGE. */ |
28 | #include <linux/types.h> |
29 | #include <linux/virtio_types.h> |
30 | #include <linux/virtio_ids.h> |
31 | #include <linux/virtio_config.h> |
32 | |
33 | /* The feature bitmap for virtio balloon */ |
34 | #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ |
35 | #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ |
36 | #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ |
37 | #define VIRTIO_BALLOON_F_FREE_PAGE_HINT 3 /* VQ to report free pages */ |
38 | #define VIRTIO_BALLOON_F_PAGE_POISON 4 /* Guest is using page poisoning */ |
39 | #define VIRTIO_BALLOON_F_REPORTING 5 /* Page reporting virtqueue */ |
40 | |
41 | /* Size of a PFN in the balloon interface. */ |
42 | #define VIRTIO_BALLOON_PFN_SHIFT 12 |
43 | |
44 | #define VIRTIO_BALLOON_CMD_ID_STOP 0 |
45 | #define VIRTIO_BALLOON_CMD_ID_DONE 1 |
46 | struct virtio_balloon_config { |
47 | /* Number of pages host wants Guest to give up. */ |
48 | __le32 num_pages; |
49 | /* Number of pages we've actually got in balloon. */ |
50 | __le32 actual; |
51 | /* |
52 | * Free page hint command id, readonly by guest. |
53 | * Was previously named free_page_report_cmd_id so we |
54 | * need to carry that name for legacy support. |
55 | */ |
56 | union { |
57 | __le32 free_page_hint_cmd_id; |
58 | __le32 free_page_report_cmd_id; /* deprecated */ |
59 | }; |
60 | /* Stores PAGE_POISON if page poisoning is in use */ |
61 | __le32 poison_val; |
62 | }; |
63 | |
64 | #define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ |
65 | #define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */ |
66 | #define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */ |
67 | #define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */ |
68 | #define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */ |
69 | #define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */ |
70 | #define VIRTIO_BALLOON_S_AVAIL 6 /* Available memory as in /proc */ |
71 | #define VIRTIO_BALLOON_S_CACHES 7 /* Disk caches */ |
72 | #define VIRTIO_BALLOON_S_HTLB_PGALLOC 8 /* Hugetlb page allocations */ |
73 | #define VIRTIO_BALLOON_S_HTLB_PGFAIL 9 /* Hugetlb page allocation failures */ |
74 | #define VIRTIO_BALLOON_S_NR 10 |
75 | |
76 | #define VIRTIO_BALLOON_S_NAMES_WITH_PREFIX(VIRTIO_BALLOON_S_NAMES_prefix) { \ |
77 | VIRTIO_BALLOON_S_NAMES_prefix "swap-in", \ |
78 | VIRTIO_BALLOON_S_NAMES_prefix "swap-out", \ |
79 | VIRTIO_BALLOON_S_NAMES_prefix "major-faults", \ |
80 | VIRTIO_BALLOON_S_NAMES_prefix "minor-faults", \ |
81 | VIRTIO_BALLOON_S_NAMES_prefix "free-memory", \ |
82 | VIRTIO_BALLOON_S_NAMES_prefix "total-memory", \ |
83 | VIRTIO_BALLOON_S_NAMES_prefix "available-memory", \ |
84 | VIRTIO_BALLOON_S_NAMES_prefix "disk-caches", \ |
85 | VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-allocations", \ |
86 | VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-failures" \ |
87 | } |
88 | |
89 | #define VIRTIO_BALLOON_S_NAMES VIRTIO_BALLOON_S_NAMES_WITH_PREFIX("") |
90 | |
91 | /* |
92 | * Memory statistics structure. |
93 | * Driver fills an array of these structures and passes to device. |
94 | * |
95 | * NOTE: fields are laid out in a way that would make compiler add padding |
96 | * between and after fields, so we have to use compiler-specific attributes to |
97 | * pack it, to disable this padding. This also often causes compiler to |
98 | * generate suboptimal code. |
99 | * |
100 | * We maintain this statistics structure format for backwards compatibility, |
101 | * but don't follow this example. |
102 | * |
103 | * If implementing a similar structure, do something like the below instead: |
104 | * struct virtio_balloon_stat { |
105 | * __virtio16 tag; |
106 | * __u8 reserved[6]; |
107 | * __virtio64 val; |
108 | * }; |
109 | * |
110 | * In other words, add explicit reserved fields to align field and |
111 | * structure boundaries at field size, avoiding compiler padding |
112 | * without the packed attribute. |
113 | */ |
114 | struct virtio_balloon_stat { |
115 | __virtio16 tag; |
116 | __virtio64 val; |
117 | } __attribute__((packed)); |
118 | |
119 | #endif /* _LINUX_VIRTIO_BALLOON_H */ |
120 | |