[linux-2.6-block.git] / include / uapi / linux / virtio_balloon.h

#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_OOM_KILL      10 /* OOM killer invocations */
#define VIRTIO_BALLOON_S_ALLOC_STALL   11 /* Stall count of memory allocatoin */
#define VIRTIO_BALLOON_S_ASYNC_SCAN    12 /* Amount of memory scanned asynchronously */
#define VIRTIO_BALLOON_S_DIRECT_SCAN   13 /* Amount of memory scanned directly */
#define VIRTIO_BALLOON_S_ASYNC_RECLAIM 14 /* Amount of memory reclaimed asynchronously */
#define VIRTIO_BALLOON_S_DIRECT_RECLAIM 15 /* Amount of memory reclaimed directly */
#define VIRTIO_BALLOON_S_NR       16

#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", \
	VIRTIO_BALLOON_S_NAMES_prefix "oom-kills", \
	VIRTIO_BALLOON_S_NAMES_prefix "alloc-stalls", \
	VIRTIO_BALLOON_S_NAMES_prefix "async-scans", \
	VIRTIO_BALLOON_S_NAMES_prefix "direct-scans", \
	VIRTIO_BALLOON_S_NAMES_prefix "async-reclaims", \
	VIRTIO_BALLOON_S_NAMES_prefix "direct-reclaims" \
}

#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 */
Commit	Line	Data
	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_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 16
	81
	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 padding
	108	* between and after fields, so we have to use compiler-specific attributes to
	109	* pack it, to disable this padding. This also often causes compiler to
	110	* 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 and
	123	* structure boundaries at field size, avoiding compiler padding
	124	* without the packed attribute.
	125	*/
	126	struct virtio_balloon_stat {
	127	__virtio16 tag;
	128	__virtio64 val;
	129	} __attribute__((packed));
	130
	131	#endif /* _LINUX_VIRTIO_BALLOON_H */