LXR qemu/include/standard-headers/linux/virtio

   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 "standard-headers/linux/types.h"
  29#include "standard-headers/linux/virtio_types.h"
  30#include "standard-headers/linux/virtio_ids.h"
  31#include "standard-headers/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
  46struct virtio_balloon_config {
  47        /* Number of pages host wants Guest to give up. */
  48        uint32_t num_pages;
  49        /* Number of pages we've actually got in balloon. */
  50        uint32_t 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                uint32_t free_page_hint_cmd_id;
  58                uint32_t free_page_report_cmd_id;       /* deprecated */
  59        };
  60        /* Stores PAGE_POISON if page poisoning is in use */
  61        uint32_t 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 *         uint8_t 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 */
 114struct virtio_balloon_stat {
 115        __virtio16 tag;
 116        __virtio64 val;
 117} QEMU_PACKED;
 118
 119#endif /* _LINUX_VIRTIO_BALLOON_H */
 120