| 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 | |
| 39 | /* Size of a PFN in the balloon interface. */ |
| 40 | #define VIRTIO_BALLOON_PFN_SHIFT 12 |
| 41 | |
| 42 | #define VIRTIO_BALLOON_CMD_ID_STOP 0 |
| 43 | #define VIRTIO_BALLOON_CMD_ID_DONE 1 |
| 44 | struct virtio_balloon_config { |
| 45 | /* Number of pages host wants Guest to give up. */ |
| 46 | __u32 num_pages; |
| 47 | /* Number of pages we've actually got in balloon. */ |
| 48 | __u32 actual; |
| 49 | /* Free page report command id, readonly by guest */ |
| 50 | __u32 free_page_report_cmd_id; |
| 51 | }; |
| 52 | |
| 53 | #define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ |
| 54 | #define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */ |
| 55 | #define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */ |
| 56 | #define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */ |
| 57 | #define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */ |
| 58 | #define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */ |
| 59 | #define VIRTIO_BALLOON_S_AVAIL 6 /* Available memory as in /proc */ |
| 60 | #define VIRTIO_BALLOON_S_CACHES 7 /* Disk caches */ |
| 61 | #define VIRTIO_BALLOON_S_HTLB_PGALLOC 8 /* Hugetlb page allocations */ |
| 62 | #define VIRTIO_BALLOON_S_HTLB_PGFAIL 9 /* Hugetlb page allocation failures */ |
| 63 | #define VIRTIO_BALLOON_S_NR 10 |
| 64 | |
| 65 | #define VIRTIO_BALLOON_S_NAMES_WITH_PREFIX(VIRTIO_BALLOON_S_NAMES_prefix) { \ |
| 66 | VIRTIO_BALLOON_S_NAMES_prefix "swap-in", \ |
| 67 | VIRTIO_BALLOON_S_NAMES_prefix "swap-out", \ |
| 68 | VIRTIO_BALLOON_S_NAMES_prefix "major-faults", \ |
| 69 | VIRTIO_BALLOON_S_NAMES_prefix "minor-faults", \ |
| 70 | VIRTIO_BALLOON_S_NAMES_prefix "free-memory", \ |
| 71 | VIRTIO_BALLOON_S_NAMES_prefix "total-memory", \ |
| 72 | VIRTIO_BALLOON_S_NAMES_prefix "available-memory", \ |
| 73 | VIRTIO_BALLOON_S_NAMES_prefix "disk-caches", \ |
| 74 | VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-allocations", \ |
| 75 | VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-failures" \ |
| 76 | } |
| 77 | |
| 78 | #define VIRTIO_BALLOON_S_NAMES VIRTIO_BALLOON_S_NAMES_WITH_PREFIX("") |
| 79 | |
| 80 | /* |
| 81 | * Memory statistics structure. |
| 82 | * Driver fills an array of these structures and passes to device. |
| 83 | * |
| 84 | * NOTE: fields are laid out in a way that would make compiler add padding |
| 85 | * between and after fields, so we have to use compiler-specific attributes to |
| 86 | * pack it, to disable this padding. This also often causes compiler to |
| 87 | * generate suboptimal code. |
| 88 | * |
| 89 | * We maintain this statistics structure format for backwards compatibility, |
| 90 | * but don't follow this example. |
| 91 | * |
| 92 | * If implementing a similar structure, do something like the below instead: |
| 93 | * struct virtio_balloon_stat { |
| 94 | * __virtio16 tag; |
| 95 | * __u8 reserved[6]; |
| 96 | * __virtio64 val; |
| 97 | * }; |
| 98 | * |
| 99 | * In other words, add explicit reserved fields to align field and |
| 100 | * structure boundaries at field size, avoiding compiler padding |
| 101 | * without the packed attribute. |
| 102 | */ |
| 103 | struct virtio_balloon_stat { |
| 104 | __virtio16 tag; |
| 105 | __virtio64 val; |
| 106 | } __attribute__((packed)); |
| 107 | |
| 108 | #endif /* _LINUX_VIRTIO_BALLOON_H */ |