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1#ifndef _LINUX_VIRTIO_BALLOON_H2#define _LINUX_VIRTIO_BALLOON_H3/* This header is BSD licensed so anyone can use the definitions to implement4 * compatible drivers/servers.5 *6 * Redistribution and use in source and binary forms, with or without7 * modification, are permitted provided that the following conditions8 * are met:9 * 1. Redistributions of source code must retain the above copyright10 * notice, this list of conditions and the following disclaimer.11 * 2. Redistributions in binary form must reproduce the above copyright12 * notice, this list of conditions and the following disclaimer in the13 * documentation and/or other materials provided with the distribution.14 * 3. Neither the name of IBM nor the names of its contributors15 * may be used to endorse or promote products derived from this software16 * without specific prior written permission.17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE20 * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF27 * 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 1243 44#define VIRTIO_BALLOON_CMD_ID_STOP 045#define VIRTIO_BALLOON_CMD_ID_DONE 146struct 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 we54 * 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_OOM_KILL 10 /* OOM killer invocations */75#define VIRTIO_BALLOON_S_ALLOC_STALL 11 /* Stall count of memory allocatoin */76#define VIRTIO_BALLOON_S_ASYNC_SCAN 12 /* Amount of memory scanned asynchronously */77#define VIRTIO_BALLOON_S_DIRECT_SCAN 13 /* Amount of memory scanned directly */78#define VIRTIO_BALLOON_S_ASYNC_RECLAIM 14 /* Amount of memory reclaimed asynchronously */79#define VIRTIO_BALLOON_S_DIRECT_RECLAIM 15 /* Amount of memory reclaimed directly */80#define VIRTIO_BALLOON_S_NR 1681 82#define VIRTIO_BALLOON_S_NAMES_WITH_PREFIX(VIRTIO_BALLOON_S_NAMES_prefix) { \83 VIRTIO_BALLOON_S_NAMES_prefix "swap-in", \84 VIRTIO_BALLOON_S_NAMES_prefix "swap-out", \85 VIRTIO_BALLOON_S_NAMES_prefix "major-faults", \86 VIRTIO_BALLOON_S_NAMES_prefix "minor-faults", \87 VIRTIO_BALLOON_S_NAMES_prefix "free-memory", \88 VIRTIO_BALLOON_S_NAMES_prefix "total-memory", \89 VIRTIO_BALLOON_S_NAMES_prefix "available-memory", \90 VIRTIO_BALLOON_S_NAMES_prefix "disk-caches", \91 VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-allocations", \92 VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-failures", \93 VIRTIO_BALLOON_S_NAMES_prefix "oom-kills", \94 VIRTIO_BALLOON_S_NAMES_prefix "alloc-stalls", \95 VIRTIO_BALLOON_S_NAMES_prefix "async-scans", \96 VIRTIO_BALLOON_S_NAMES_prefix "direct-scans", \97 VIRTIO_BALLOON_S_NAMES_prefix "async-reclaims", \98 VIRTIO_BALLOON_S_NAMES_prefix "direct-reclaims" \99}100 101#define VIRTIO_BALLOON_S_NAMES VIRTIO_BALLOON_S_NAMES_WITH_PREFIX("")102 103/*104 * Memory statistics structure.105 * Driver fills an array of these structures and passes to device.106 *107 * NOTE: fields are laid out in a way that would make compiler add padding108 * between and after fields, so we have to use compiler-specific attributes to109 * pack it, to disable this padding. This also often causes compiler to110 * generate suboptimal code.111 *112 * We maintain this statistics structure format for backwards compatibility,113 * but don't follow this example.114 *115 * If implementing a similar structure, do something like the below instead:116 * struct virtio_balloon_stat {117 * __virtio16 tag;118 * __u8 reserved[6];119 * __virtio64 val;120 * };121 *122 * In other words, add explicit reserved fields to align field and123 * structure boundaries at field size, avoiding compiler padding124 * without the packed attribute.125 */126struct virtio_balloon_stat {127 __virtio16 tag;128 __virtio64 val;129} __attribute__((packed));130 131#endif /* _LINUX_VIRTIO_BALLOON_H */132