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Diffstat (limited to 'include/uapi/linux/virtio_balloon.h')
| -rw-r--r-- | include/uapi/linux/virtio_balloon.h | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h new file mode 100644 index 000000000..ddaa45e72 --- /dev/null +++ b/include/uapi/linux/virtio_balloon.h @@ -0,0 +1,119 @@ +#ifndef _LINUX_VIRTIO_BALLOON_H +#define _LINUX_VIRTIO_BALLOON_H +/* This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of IBM nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. */ +#include <linux/types.h> +#include <linux/virtio_types.h> +#include <linux/virtio_ids.h> +#include <linux/virtio_config.h> + +/* The feature bitmap for virtio balloon */ +#define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ +#define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ +#define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ +#define VIRTIO_BALLOON_F_FREE_PAGE_HINT 3 /* VQ to report free pages */ +#define VIRTIO_BALLOON_F_PAGE_POISON 4 /* Guest is using page poisoning */ +#define VIRTIO_BALLOON_F_REPORTING 5 /* Page reporting virtqueue */ + +/* Size of a PFN in the balloon interface. */ +#define VIRTIO_BALLOON_PFN_SHIFT 12 + +#define VIRTIO_BALLOON_CMD_ID_STOP 0 +#define VIRTIO_BALLOON_CMD_ID_DONE 1 +struct virtio_balloon_config { + /* Number of pages host wants Guest to give up. */ + __le32 num_pages; + /* Number of pages we've actually got in balloon. */ + __le32 actual; + /* + * Free page hint command id, readonly by guest. + * Was previously named free_page_report_cmd_id so we + * need to carry that name for legacy support. + */ + union { + __le32 free_page_hint_cmd_id; + __le32 free_page_report_cmd_id; /* deprecated */ + }; + /* Stores PAGE_POISON if page poisoning is in use */ + __le32 poison_val; +}; + +#define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ +#define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */ +#define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */ +#define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */ +#define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */ +#define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */ +#define VIRTIO_BALLOON_S_AVAIL 6 /* Available memory as in /proc */ +#define VIRTIO_BALLOON_S_CACHES 7 /* Disk caches */ +#define VIRTIO_BALLOON_S_HTLB_PGALLOC 8 /* Hugetlb page allocations */ +#define VIRTIO_BALLOON_S_HTLB_PGFAIL 9 /* Hugetlb page allocation failures */ +#define VIRTIO_BALLOON_S_NR 10 + +#define VIRTIO_BALLOON_S_NAMES_WITH_PREFIX(VIRTIO_BALLOON_S_NAMES_prefix) { \ + VIRTIO_BALLOON_S_NAMES_prefix "swap-in", \ + VIRTIO_BALLOON_S_NAMES_prefix "swap-out", \ + VIRTIO_BALLOON_S_NAMES_prefix "major-faults", \ + VIRTIO_BALLOON_S_NAMES_prefix "minor-faults", \ + VIRTIO_BALLOON_S_NAMES_prefix "free-memory", \ + VIRTIO_BALLOON_S_NAMES_prefix "total-memory", \ + VIRTIO_BALLOON_S_NAMES_prefix "available-memory", \ + VIRTIO_BALLOON_S_NAMES_prefix "disk-caches", \ + VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-allocations", \ + VIRTIO_BALLOON_S_NAMES_prefix "hugetlb-failures" \ +} + +#define VIRTIO_BALLOON_S_NAMES VIRTIO_BALLOON_S_NAMES_WITH_PREFIX("") + +/* + * Memory statistics structure. + * Driver fills an array of these structures and passes to device. + * + * NOTE: fields are laid out in a way that would make compiler add padding + * between and after fields, so we have to use compiler-specific attributes to + * pack it, to disable this padding. This also often causes compiler to + * generate suboptimal code. + * + * We maintain this statistics structure format for backwards compatibility, + * but don't follow this example. + * + * If implementing a similar structure, do something like the below instead: + * struct virtio_balloon_stat { + * __virtio16 tag; + * __u8 reserved[6]; + * __virtio64 val; + * }; + * + * In other words, add explicit reserved fields to align field and + * structure boundaries at field size, avoiding compiler padding + * without the packed attribute. + */ +struct virtio_balloon_stat { + __virtio16 tag; + __virtio64 val; +} __attribute__((packed)); + +#endif /* _LINUX_VIRTIO_BALLOON_H */ |