savevm.c

/*
 * QEMU System Emulator
 *
 * Copyright (c) 2003-2008 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <errno.h>
#include <sys/time.h>
#include <zlib.h>

/* Needed early for CONFIG_BSD etc. */
#include "config-host.h"

#ifndef _WIN32
#include <sys/times.h>
#include <sys/wait.h>
#include <termios.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <dirent.h>
#include <netdb.h>
#include <sys/select.h>
#ifdef CONFIG_BSD
#include <sys/stat.h>
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
#include <libutil.h>
#else
#include <util.h>
#endif
#ifdef __linux__
#include <pty.h>
#include <malloc.h>
#include <linux/rtc.h>
#endif
#endif
#endif

#ifdef _WIN32
#include <windows.h>
#include <malloc.h>
#include <sys/timeb.h>
#include <mmsystem.h>
#define getopt_long_only getopt_long
#define memalign(align, size) malloc(size)
#endif

#include "qemu-common.h"
#include "hw/hw.h"
#include "hw/qdev.h"
#include "net.h"
#include "monitor.h"
#include "sysemu.h"
#include "qemu-timer.h"
#include "qemu-char.h"
#include "audio/audio.h"
#include "migration.h"
#include "qemu_socket.h"
#include "qemu-queue.h"
#include "qemu-timer.h"
#include "cpus.h"

#define SELF_ANNOUNCE_ROUNDS 5

#ifndef ETH_P_RARP
#define ETH_P_RARP 0x8035
#endif
#define ARP_HTYPE_ETH 0x0001
#define ARP_PTYPE_IP 0x0800
#define ARP_OP_REQUEST_REV 0x3

static int announce_self_create(uint8_t *buf,
				uint8_t *mac_addr)
{
    /* Ethernet header. */
    memset(buf, 0xff, 6);         /* destination MAC addr */
    memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
    *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */

    /* RARP header. */
    *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
    *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
    *(buf + 18) = 6; /* hardware addr length (ethernet) */
    *(buf + 19) = 4; /* protocol addr length (IPv4) */
    *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
    memcpy(buf + 22, mac_addr, 6); /* source hw addr */
    memset(buf + 28, 0x00, 4);     /* source protocol addr */
    memcpy(buf + 32, mac_addr, 6); /* target hw addr */
    memset(buf + 38, 0x00, 4);     /* target protocol addr */

    /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
    memset(buf + 42, 0x00, 18);

    return 60; /* len (FCS will be added by hardware) */
}

static void qemu_announce_self_iter(NICState *nic, void *opaque)
{
    uint8_t buf[60];
    int len;

    len = announce_self_create(buf, nic->conf->macaddr.a);

    qemu_send_packet_raw(&nic->nc, buf, len);
}


static void qemu_announce_self_once(void *opaque)
{
    static int count = SELF_ANNOUNCE_ROUNDS;
    QEMUTimer *timer = *(QEMUTimer **)opaque;

    qemu_foreach_nic(qemu_announce_self_iter, NULL);

    if (--count) {
        /* delay 50ms, 150ms, 250ms, ... */
        qemu_mod_timer(timer, qemu_get_clock_ms(rt_clock) +
                       50 + (SELF_ANNOUNCE_ROUNDS - count - 1) * 100);
    } else {
	    qemu_del_timer(timer);
	    qemu_free_timer(timer);
    }
}

void qemu_announce_self(void)
{
	static QEMUTimer *timer;
	timer = qemu_new_timer_ms(rt_clock, qemu_announce_self_once, &timer);
	qemu_announce_self_once(&timer);
}

/***********************************************************/
/* savevm/loadvm support */

#define IO_BUF_SIZE 32768

struct QEMUFile {
    QEMUFilePutBufferFunc *put_buffer;
    QEMUFileGetBufferFunc *get_buffer;
    QEMUFileCloseFunc *close;
    QEMUFileRateLimit *rate_limit;
    QEMUFileSetRateLimit *set_rate_limit;
    QEMUFileGetRateLimit *get_rate_limit;
    void *opaque;
    int is_write;

    int64_t buf_offset; /* start of buffer when writing, end of buffer
                           when reading */
    int buf_index;
    int buf_size; /* 0 when writing */
    uint8_t buf[IO_BUF_SIZE];

    int last_error;
};

typedef struct QEMUFileStdio
{
    FILE *stdio_file;
    QEMUFile *file;
} QEMUFileStdio;

typedef struct QEMUFileSocket
{
    int fd;
    QEMUFile *file;
} QEMUFileSocket;

static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
    QEMUFileSocket *s = opaque;
    ssize_t len;

    do {
        len = qemu_recv(s->fd, buf, size, 0);
    } while (len == -1 && socket_error() == EINTR);

    if (len == -1)
        len = -socket_error();

    return len;
}

static int socket_close(void *opaque)
{
    QEMUFileSocket *s = opaque;
    g_free(s);
    return 0;
}

static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
{
    QEMUFileStdio *s = opaque;
    return fwrite(buf, 1, size, s->stdio_file);
}

static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
    QEMUFileStdio *s = opaque;
    FILE *fp = s->stdio_file;
    int bytes;

    do {
        clearerr(fp);
        bytes = fread(buf, 1, size, fp);
    } while ((bytes == 0) && ferror(fp) && (errno == EINTR));
    return bytes;
}

static int stdio_pclose(void *opaque)
{
    QEMUFileStdio *s = opaque;
    int ret;
    ret = pclose(s->stdio_file);
    if (ret == -1) {
        ret = -errno;
    }
    g_free(s);
    return ret;
}

static int stdio_fclose(void *opaque)
{
    QEMUFileStdio *s = opaque;
    int ret = 0;
    if (fclose(s->stdio_file) == EOF) {
        ret = -errno;
    }
    g_free(s);
    return ret;
}

QEMUFile *qemu_popen(FILE *stdio_file, const char *mode)
{
    QEMUFileStdio *s;

    if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
        fprintf(stderr, "qemu_popen: Argument validity check failed\n");
        return NULL;
    }

    s = g_malloc0(sizeof(QEMUFileStdio));

    s->stdio_file = stdio_file;

    if(mode[0] == 'r') {
        s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_pclose, 
				 NULL, NULL, NULL);
    } else {
        s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_pclose, 
				 NULL, NULL, NULL);
    }
    return s->file;
}

QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
{
    FILE *popen_file;

    popen_file = popen(command, mode);
    if(popen_file == NULL) {
        return NULL;
    }

    return qemu_popen(popen_file, mode);
}

int qemu_stdio_fd(QEMUFile *f)
{
    QEMUFileStdio *p;
    int fd;

    p = (QEMUFileStdio *)f->opaque;
    fd = fileno(p->stdio_file);

    return fd;
}

QEMUFile *qemu_fdopen(int fd, const char *mode)
{
    QEMUFileStdio *s;

    if (mode == NULL ||
	(mode[0] != 'r' && mode[0] != 'w') ||
	mode[1] != 'b' || mode[2] != 0) {
        fprintf(stderr, "qemu_fdopen: Argument validity check failed\n");
        return NULL;
    }

    s = g_malloc0(sizeof(QEMUFileStdio));
    s->stdio_file = fdopen(fd, mode);
    if (!s->stdio_file)
        goto fail;

    if(mode[0] == 'r') {
        s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose, 
				 NULL, NULL, NULL);
    } else {
        s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose, 
				 NULL, NULL, NULL);
    }
    return s->file;

fail:
    g_free(s);
    return NULL;
}

QEMUFile *qemu_fopen_socket(int fd)
{
    QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));

    s->fd = fd;
    s->file = qemu_fopen_ops(s, NULL, socket_get_buffer, socket_close, 
			     NULL, NULL, NULL);
    return s->file;
}

static int file_put_buffer(void *opaque, const uint8_t *buf,
                            int64_t pos, int size)
{
    QEMUFileStdio *s = opaque;
    fseek(s->stdio_file, pos, SEEK_SET);
    return fwrite(buf, 1, size, s->stdio_file);
}

static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
    QEMUFileStdio *s = opaque;
    fseek(s->stdio_file, pos, SEEK_SET);
    return fread(buf, 1, size, s->stdio_file);
}

QEMUFile *qemu_fopen(const char *filename, const char *mode)
{
    QEMUFileStdio *s;

    if (mode == NULL ||
	(mode[0] != 'r' && mode[0] != 'w') ||
	mode[1] != 'b' || mode[2] != 0) {
        fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
        return NULL;
    }

    s = g_malloc0(sizeof(QEMUFileStdio));

    s->stdio_file = fopen(filename, mode);
    if (!s->stdio_file)
        goto fail;
    
    if(mode[0] == 'w') {
        s->file = qemu_fopen_ops(s, file_put_buffer, NULL, stdio_fclose, 
				 NULL, NULL, NULL);
    } else {
        s->file = qemu_fopen_ops(s, NULL, file_get_buffer, stdio_fclose, 
			       NULL, NULL, NULL);
    }
    return s->file;
fail:
    g_free(s);
    return NULL;
}

static int block_put_buffer(void *opaque, const uint8_t *buf,
                           int64_t pos, int size)
{
    bdrv_save_vmstate(opaque, buf, pos, size);
    return size;
}

static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
    return bdrv_load_vmstate(opaque, buf, pos, size);
}

static int bdrv_fclose(void *opaque)
{
    return 0;
}

static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
{
    if (is_writable)
        return qemu_fopen_ops(bs, block_put_buffer, NULL, bdrv_fclose, 
			      NULL, NULL, NULL);
    return qemu_fopen_ops(bs, NULL, block_get_buffer, bdrv_fclose, NULL, NULL, NULL);
}

QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
                         QEMUFileGetBufferFunc *get_buffer,
                         QEMUFileCloseFunc *close,
                         QEMUFileRateLimit *rate_limit,
                         QEMUFileSetRateLimit *set_rate_limit,
                         QEMUFileGetRateLimit *get_rate_limit)
{
    QEMUFile *f;

    f = g_malloc0(sizeof(QEMUFile));

    f->opaque = opaque;
    f->put_buffer = put_buffer;
    f->get_buffer = get_buffer;
    f->close = close;
    f->rate_limit = rate_limit;
    f->set_rate_limit = set_rate_limit;
    f->get_rate_limit = get_rate_limit;
    f->is_write = 0;

    return f;
}

int qemu_file_get_error(QEMUFile *f)
{
    return f->last_error;
}

void qemu_file_set_error(QEMUFile *f, int ret)
{
    f->last_error = ret;
}

/** Sets last_error conditionally
 *
 * Sets last_error only if ret is negative _and_ no error
 * was set before.
 */
static void qemu_file_set_if_error(QEMUFile *f, int ret)
{
    if (ret < 0 && !f->last_error) {
        qemu_file_set_error(f, ret);
    }
}

/** Flushes QEMUFile buffer
 *
 * In case of error, last_error is set.
 */
void qemu_fflush(QEMUFile *f)
{
    if (!f->put_buffer)
        return;

    if (f->is_write && f->buf_index > 0) {
        int len;

        len = f->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
        if (len > 0)
            f->buf_offset += f->buf_index;
        else
            qemu_file_set_error(f, -EINVAL);
        f->buf_index = 0;
    }
}

static void qemu_fill_buffer(QEMUFile *f)
{
    int len;
    int pending;

    if (!f->get_buffer)
        return;

    if (f->is_write)
        abort();

    pending = f->buf_size - f->buf_index;
    if (pending > 0) {
        memmove(f->buf, f->buf + f->buf_index, pending);
    }
    f->buf_index = 0;
    f->buf_size = pending;

    len = f->get_buffer(f->opaque, f->buf + pending, f->buf_offset,
                        IO_BUF_SIZE - pending);
    if (len > 0) {
        f->buf_size += len;
        f->buf_offset += len;
    } else if (len == 0) {
        f->last_error = -EIO;
    } else if (len != -EAGAIN)
        qemu_file_set_error(f, len);
}

/** Calls close function and set last_error if needed
 *
 * Internal function. qemu_fflush() must be called before this.
 *
 * Returns f->close() return value, or 0 if close function is not set.
 */
static int qemu_close(QEMUFile *f)
{
    int ret = 0;
    if (f->close) {
        ret = f->close(f->opaque);
        qemu_file_set_if_error(f, ret);
    }
    return ret;
}

/** Closes the file
 *
 * Returns negative error value if any error happened on previous operations or
 * while closing the file. Returns 0 or positive number on success.
 *
 * The meaning of return value on success depends on the specific backend
 * being used.
 */
int qemu_fclose(QEMUFile *f)
{
    int ret;
    qemu_fflush(f);
    ret = qemu_close(f);
    /* If any error was spotted before closing, we should report it
     * instead of the close() return value.
     */
    if (f->last_error) {
        ret = f->last_error;
    }
    g_free(f);
    return ret;
}

void qemu_file_put_notify(QEMUFile *f)
{
    f->put_buffer(f->opaque, NULL, 0, 0);
}

void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
{
    int l;

    if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
        fprintf(stderr,
                "Attempted to write to buffer while read buffer is not empty\n");
        abort();
    }

    while (!f->last_error && size > 0) {
        l = IO_BUF_SIZE - f->buf_index;
        if (l > size)
            l = size;
        memcpy(f->buf + f->buf_index, buf, l);
        f->is_write = 1;
        f->buf_index += l;
        buf += l;
        size -= l;
        if (f->buf_index >= IO_BUF_SIZE)
            qemu_fflush(f);
    }
}

void qemu_put_byte(QEMUFile *f, int v)
{
    if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
        fprintf(stderr,
                "Attempted to write to buffer while read buffer is not empty\n");
        abort();
    }

    f->buf[f->buf_index++] = v;
    f->is_write = 1;
    if (f->buf_index >= IO_BUF_SIZE)
        qemu_fflush(f);
}

static void qemu_file_skip(QEMUFile *f, int size)
{
    if (f->buf_index + size <= f->buf_size) {
        f->buf_index += size;
    }
}

static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset)
{
    int pending;
    int index;

    if (f->is_write) {
        abort();
    }

    index = f->buf_index + offset;
    pending = f->buf_size - index;
    if (pending < size) {
        qemu_fill_buffer(f);
        index = f->buf_index + offset;
        pending = f->buf_size - index;
    }

    if (pending <= 0) {
        return 0;
    }
    if (size > pending) {
        size = pending;
    }

    memcpy(buf, f->buf + index, size);
    return size;
}

int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
{
    int pending = size;
    int done = 0;

    while (pending > 0) {
        int res;

        res = qemu_peek_buffer(f, buf, pending, 0);
        if (res == 0) {
            return done;
        }
        qemu_file_skip(f, res);
        buf += res;
        pending -= res;
        done += res;
    }
    return done;
}

static int qemu_peek_byte(QEMUFile *f, int offset)
{
    int index = f->buf_index + offset;

    if (f->is_write) {
        abort();
    }

    if (index >= f->buf_size) {
        qemu_fill_buffer(f);
        index = f->buf_index + offset;
        if (index >= f->buf_size) {
            return 0;
        }
    }
    return f->buf[index];
}

int qemu_get_byte(QEMUFile *f)
{
    int result;

    result = qemu_peek_byte(f, 0);
    qemu_file_skip(f, 1);
    return result;
}

int64_t qemu_ftell(QEMUFile *f)
{
    return f->buf_offset - f->buf_size + f->buf_index;
}

int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
{
    if (whence == SEEK_SET) {
        /* nothing to do */
    } else if (whence == SEEK_CUR) {
        pos += qemu_ftell(f);
    } else {
        /* SEEK_END not supported */
        return -1;
    }
    if (f->put_buffer) {
        qemu_fflush(f);
        f->buf_offset = pos;
    } else {
        f->buf_offset = pos;
        f->buf_index = 0;
        f->buf_size = 0;
    }
    return pos;
}

int qemu_file_rate_limit(QEMUFile *f)
{
    if (f->rate_limit)
        return f->rate_limit(f->opaque);

    return 0;
}

int64_t qemu_file_get_rate_limit(QEMUFile *f)
{
    if (f->get_rate_limit)
        return f->get_rate_limit(f->opaque);

    return 0;
}

int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
{
    /* any failed or completed migration keeps its state to allow probing of
     * migration data, but has no associated file anymore */
    if (f && f->set_rate_limit)
        return f->set_rate_limit(f->opaque, new_rate);

    return 0;
}

void qemu_put_be16(QEMUFile *f, unsigned int v)
{
    qemu_put_byte(f, v >> 8);
    qemu_put_byte(f, v);
}

void qemu_put_be32(QEMUFile *f, unsigned int v)
{
    qemu_put_byte(f, v >> 24);
    qemu_put_byte(f, v >> 16);
    qemu_put_byte(f, v >> 8);
    qemu_put_byte(f, v);
}

void qemu_put_be64(QEMUFile *f, uint64_t v)
{
    qemu_put_be32(f, v >> 32);
    qemu_put_be32(f, v);
}

unsigned int qemu_get_be16(QEMUFile *f)
{
    unsigned int v;
    v = qemu_get_byte(f) << 8;
    v |= qemu_get_byte(f);
    return v;
}

unsigned int qemu_get_be32(QEMUFile *f)
{
    unsigned int v;
    v = qemu_get_byte(f) << 24;
    v |= qemu_get_byte(f) << 16;
    v |= qemu_get_byte(f) << 8;
    v |= qemu_get_byte(f);
    return v;
}

uint64_t qemu_get_be64(QEMUFile *f)
{
    uint64_t v;
    v = (uint64_t)qemu_get_be32(f) << 32;
    v |= qemu_get_be32(f);
    return v;
}


/* timer */

void qemu_put_timer(QEMUFile *f, QEMUTimer *ts)
{
    uint64_t expire_time;

    expire_time = qemu_timer_expire_time_ns(ts);
    qemu_put_be64(f, expire_time);
}

void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
{
    uint64_t expire_time;

    expire_time = qemu_get_be64(f);
    if (expire_time != -1) {
        qemu_mod_timer_ns(ts, expire_time);
    } else {
        qemu_del_timer(ts);
    }
}


/* bool */

static int get_bool(QEMUFile *f, void *pv, size_t size)
{
    bool *v = pv;
    *v = qemu_get_byte(f);
    return 0;
}

static void put_bool(QEMUFile *f, void *pv, size_t size)
{
    bool *v = pv;
    qemu_put_byte(f, *v);
}

const VMStateInfo vmstate_info_bool = {
    .name = "bool",
    .get  = get_bool,
    .put  = put_bool,
};

/* 8 bit int */

static int get_int8(QEMUFile *f, void *pv, size_t size)
{
    int8_t *v = pv;
    qemu_get_s8s(f, v);
    return 0;
}

static void put_int8(QEMUFile *f, void *pv, size_t size)
{
    int8_t *v = pv;
    qemu_put_s8s(f, v);
}

const VMStateInfo vmstate_info_int8 = {
    .name = "int8",
    .get  = get_int8,
    .put  = put_int8,
};

/* 16 bit int */

static int get_int16(QEMUFile *f, void *pv, size_t size)
{
    int16_t *v = pv;
    qemu_get_sbe16s(f, v);
    return 0;
}

static void put_int16(QEMUFile *f, void *pv, size_t size)
{
    int16_t *v = pv;
    qemu_put_sbe16s(f, v);
}

const VMStateInfo vmstate_info_int16 = {
    .name = "int16",
    .get  = get_int16,
    .put  = put_int16,
};

/* 32 bit int */

static int get_int32(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    qemu_get_sbe32s(f, v);
    return 0;
}

static void put_int32(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    qemu_put_sbe32s(f, v);
}

const VMStateInfo vmstate_info_int32 = {
    .name = "int32",
    .get  = get_int32,
    .put  = put_int32,
};

/* 32 bit int. See that the received value is the same than the one
   in the field */

static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    int32_t v2;
    qemu_get_sbe32s(f, &v2);

    if (*v == v2)
        return 0;
    return -EINVAL;
}

const VMStateInfo vmstate_info_int32_equal = {
    .name = "int32 equal",
    .get  = get_int32_equal,
    .put  = put_int32,
};

/* 32 bit int. See that the received value is the less or the same
   than the one in the field */

static int get_int32_le(QEMUFile *f, void *pv, size_t size)
{
    int32_t *old = pv;
    int32_t new;
    qemu_get_sbe32s(f, &new);

    if (*old <= new)
        return 0;
    return -EINVAL;
}

const VMStateInfo vmstate_info_int32_le = {
    .name = "int32 equal",
    .get  = get_int32_le,
    .put  = put_int32,
};

/* 64 bit int */

static int get_int64(QEMUFile *f, void *pv, size_t size)
{
    int64_t *v = pv;
    qemu_get_sbe64s(f, v);
    return 0;
}

static void put_int64(QEMUFile *f, void *pv, size_t size)
{
    int64_t *v = pv;
    qemu_put_sbe64s(f, v);
}

const VMStateInfo vmstate_info_int64 = {
    .name = "int64",
    .get  = get_int64,
    .put  = put_int64,
};

/* 8 bit unsigned int */

static int get_uint8(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_get_8s(f, v);
    return 0;
}

static void put_uint8(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_put_8s(f, v);
}

const VMStateInfo vmstate_info_uint8 = {
    .name = "uint8",
    .get  = get_uint8,
    .put  = put_uint8,
};

/* 16 bit unsigned int */

static int get_uint16(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    qemu_get_be16s(f, v);
    return 0;
}

static void put_uint16(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    qemu_put_be16s(f, v);
}

const VMStateInfo vmstate_info_uint16 = {
    .name = "uint16",
    .get  = get_uint16,
    .put  = put_uint16,
};

/* 32 bit unsigned int */

static int get_uint32(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    qemu_get_be32s(f, v);
    return 0;
}

static void put_uint32(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    qemu_put_be32s(f, v);
}

const VMStateInfo vmstate_info_uint32 = {
    .name = "uint32",
    .get  = get_uint32,
    .put  = put_uint32,
};

/* 32 bit uint. See that the received value is the same than the one
   in the field */

static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    uint32_t v2;
    qemu_get_be32s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint32_equal = {
    .name = "uint32 equal",
    .get  = get_uint32_equal,
    .put  = put_uint32,
};

/* 64 bit unsigned int */

static int get_uint64(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;
    qemu_get_be64s(f, v);
    return 0;
}

static void put_uint64(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;
    qemu_put_be64s(f, v);
}

const VMStateInfo vmstate_info_uint64 = {
    .name = "uint64",
    .get  = get_uint64,
    .put  = put_uint64,
};

/* 8 bit int. See that the received value is the same than the one
   in the field */

static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    uint8_t v2;
    qemu_get_8s(f, &v2);

    if (*v == v2)
        return 0;
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint8_equal = {
    .name = "uint8 equal",
    .get  = get_uint8_equal,
    .put  = put_uint8,
};

/* 16 bit unsigned int int. See that the received value is the same than the one
   in the field */

static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    uint16_t v2;
    qemu_get_be16s(f, &v2);

    if (*v == v2)
        return 0;
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint16_equal = {
    .name = "uint16 equal",
    .get  = get_uint16_equal,
    .put  = put_uint16,
};

/* timers  */

static int get_timer(QEMUFile *f, void *pv, size_t size)
{
    QEMUTimer *v = pv;
    qemu_get_timer(f, v);
    return 0;
}

static void put_timer(QEMUFile *f, void *pv, size_t size)
{
    QEMUTimer *v = pv;
    qemu_put_timer(f, v);
}

const VMStateInfo vmstate_info_timer = {
    .name = "timer",
    .get  = get_timer,
    .put  = put_timer,
};

/* uint8_t buffers */

static int get_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_get_buffer(f, v, size);
    return 0;
}

static void put_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_put_buffer(f, v, size);
}

const VMStateInfo vmstate_info_buffer = {
    .name = "buffer",
    .get  = get_buffer,
    .put  = put_buffer,
};

/* unused buffers: space that was used for some fields that are
   not useful anymore */

static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t buf[1024];
    int block_len;

    while (size > 0) {
        block_len = MIN(sizeof(buf), size);
        size -= block_len;
        qemu_get_buffer(f, buf, block_len);
    }
   return 0;
}

static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
    static const uint8_t buf[1024];
    int block_len;

    while (size > 0) {
        block_len = MIN(sizeof(buf), size);
        size -= block_len;
        qemu_put_buffer(f, buf, block_len);
    }
}

const VMStateInfo vmstate_info_unused_buffer = {
    .name = "unused_buffer",
    .get  = get_unused_buffer,
    .put  = put_unused_buffer,
};

typedef struct CompatEntry {
    char idstr[256];
    int instance_id;
} CompatEntry;

typedef struct SaveStateEntry {
    QTAILQ_ENTRY(SaveStateEntry) entry;
    char idstr[256];
    int instance_id;
    int alias_id;
    int version_id;
    int section_id;
    SaveSetParamsHandler *set_params;
    SaveLiveStateHandler *save_live_state;
    SaveStateHandler *save_state;
    LoadStateHandler *load_state;
    const VMStateDescription *vmsd;
    void *opaque;
    CompatEntry *compat;
    int no_migrate;
} SaveStateEntry;


static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
    QTAILQ_HEAD_INITIALIZER(savevm_handlers);
static int global_section_id;

static int calculate_new_instance_id(const char *idstr)
{
    SaveStateEntry *se;
    int instance_id = 0;

    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
        if (strcmp(idstr, se->idstr) == 0
            && instance_id <= se->instance_id) {
            instance_id = se->instance_id + 1;
        }
    }
    return instance_id;
}

static int calculate_compat_instance_id(const char *idstr)
{
    SaveStateEntry *se;
    int instance_id = 0;

    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
        if (!se->compat)
            continue;

        if (strcmp(idstr, se->compat->idstr) == 0
            && instance_id <= se->compat->instance_id) {
            instance_id = se->compat->instance_id + 1;
        }
    }
    return instance_id;
}

/* TODO: Individual devices generally have very little idea about the rest
   of the system, so instance_id should be removed/replaced.
   Meanwhile pass -1 as instance_id if you do not already have a clearly
   distinguishing id for all instances of your device class. */
int register_savevm_live(DeviceState *dev,
                         const char *idstr,
                         int instance_id,
                         int version_id,
                         SaveSetParamsHandler *set_params,
                         SaveLiveStateHandler *save_live_state,
                         SaveStateHandler *save_state,
                         LoadStateHandler *load_state,
                         void *opaque)
{
    SaveStateEntry *se;

    se = g_malloc0(sizeof(SaveStateEntry));
    se->version_id = version_id;
    se->section_id = global_section_id++;
    se->set_params = set_params;
    se->save_live_state = save_live_state;
    se->save_state = save_state;
    se->load_state = load_state;
    se->opaque = opaque;
    se->vmsd = NULL;
    se->no_migrate = 0;

    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
        char *id = dev->parent_bus->info->get_dev_path(dev);
        if (id) {
            pstrcpy(se->idstr, sizeof(se->idstr), id);
            pstrcat(se->idstr, sizeof(se->idstr), "/");
            g_free(id);

            se->compat = g_malloc0(sizeof(CompatEntry));
            pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
            se->compat->instance_id = instance_id == -1 ?
                         calculate_compat_instance_id(idstr) : instance_id;
            instance_id = -1;
        }
    }
    pstrcat(se->idstr, sizeof(se->idstr), idstr);

    if (instance_id == -1) {
        se->instance_id = calculate_new_instance_id(se->idstr);
    } else {
        se->instance_id = instance_id;
    }
    assert(!se->compat || se->instance_id == 0);
    /* add at the end of list */
    QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
    return 0;
}

int register_savevm(DeviceState *dev,
                    const char *idstr,
                    int instance_id,
                    int version_id,
                    SaveStateHandler *save_state,
                    LoadStateHandler *load_state,
                    void *opaque)
{
    return register_savevm_live(dev, idstr, instance_id, version_id,
                                NULL, NULL, save_state, load_state, opaque);
}

void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
{
    SaveStateEntry *se, *new_se;
    char id[256] = "";

    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
        char *path = dev->parent_bus->info->get_dev_path(dev);
        if (path) {
            pstrcpy(id, sizeof(id), path);
            pstrcat(id, sizeof(id), "/");
            g_free(path);
        }
    }
    pstrcat(id, sizeof(id), idstr);

    QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
        if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
            QTAILQ_REMOVE(&savevm_handlers, se, entry);
            if (se->compat) {
                g_free(se->compat);
            }
            g_free(se);
        }
    }
}

int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
                                   const VMStateDescription *vmsd,
                                   void *opaque, int alias_id,
                                   int required_for_version)
{
    SaveStateEntry *se;

    /* If this triggers, alias support can be dropped for the vmsd. */
    assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);

    se = g_malloc0(sizeof(SaveStateEntry));
    se->version_id = vmsd->version_id;
    se->section_id = global_section_id++;
    se->save_live_state = NULL;
    se->save_state = NULL;
    se->load_state = NULL;
    se->opaque = opaque;
    se->vmsd = vmsd;
    se->alias_id = alias_id;
    se->no_migrate = vmsd->unmigratable;

    if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) {
        char *id = dev->parent_bus->info->get_dev_path(dev);
        if (id) {
            pstrcpy(se->idstr, sizeof(se->idstr), id);
            pstrcat(se->idstr, sizeof(se->idstr), "/");
            g_free(id);

            se->compat = g_malloc0(sizeof(CompatEntry));
            pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
            se->compat->instance_id = instance_id == -1 ?
                         calculate_compat_instance_id(vmsd->name) : instance_id;
            instance_id = -1;
        }
    }
    pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);

    if (instance_id == -1) {
        se->instance_id = calculate_new_instance_id(se->idstr);
    } else {
        se->instance_id = instance_id;
    }
    assert(!se->compat || se->instance_id == 0);
    /* add at the end of list */
    QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
    return 0;
}

int vmstate_register(DeviceState *dev, int instance_id,
                     const VMStateDescription *vmsd, void *opaque)
{
    return vmstate_register_with_alias_id(dev, instance_id, vmsd,
                                          opaque, -1, 0);
}

void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
                        void *opaque)
{
    SaveStateEntry *se, *new_se;

    QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
        if (se->vmsd == vmsd && se->opaque == opaque) {
            QTAILQ_REMOVE(&savevm_handlers, se, entry);
            if (se->compat) {
                g_free(se->compat);
            }
            g_free(se);
        }
    }