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qemu/savevm.c
lirans@il.ibm.com c163b5cae9 Block live migration 
This patch introduces block migration called during live migration. Block
are being copied to the destination in an async way. First the code will
transfer the whole disk and then transfer all dirty blocks accumulted during
the migration.
Still need to improve transition from the iterative phase of migration to the
end phase. For now transition will take place when all blocks transfered once,
all the dirty blocks will be transfered during the end phase (guest is
suspended).

Changes from v4:
- Global variabels moved to a global state structure allocated dynamically.
- Minor coding style issues.
- Poll block.c for tracking of dirty blocks instead of manage it here.

Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17 08:49:30 -06:00

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/*
* 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 <signal.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(__DragonFly__)
#include <libutil.h>
#else
#include <util.h>
#endif
#elif defined (__GLIBC__) && defined (__FreeBSD_kernel__)
#include <freebsd/stdlib.h>
#else
#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 "net.h"
#include "monitor.h"
#include "sysemu.h"
#include "qemu-timer.h"
#include "qemu-char.h"
#include "block.h"
#include "audio/audio.h"
#include "migration.h"
#include "qemu_socket.h"
#include "qemu-queue.h"
/* point to the block driver where the snapshots are managed */
static BlockDriverState *bs_snapshots;
#define SELF_ANNOUNCE_ROUNDS 5
#ifndef ETH_P_RARP
#define ETH_P_RARP 0x0835
#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_once(void *opaque)
{
int i, len;
VLANState *vlan;
VLANClientState *vc;
uint8_t buf[60];
static int count = SELF_ANNOUNCE_ROUNDS;
QEMUTimer *timer = *(QEMUTimer **)opaque;
for (i = 0; i < MAX_NICS; i++) {
if (!nd_table[i].used)
continue;
len = announce_self_create(buf, nd_table[i].macaddr);
vlan = nd_table[i].vlan;
QTAILQ_FOREACH(vc, &vlan->clients, next) {
qemu_send_packet_raw(vc, buf, len);
}
}
if (--count) {
/* delay 50ms, 150ms, 250ms, ... */
qemu_mod_timer(timer, qemu_get_clock(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(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 has_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 = recv(s->fd, (void *)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;
qemu_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;
pclose(s->stdio_file);
qemu_free(s);
return 0;
}
static int stdio_fclose(void *opaque)
{
QEMUFileStdio *s = opaque;
fclose(s->stdio_file);
qemu_free(s);
return 0;
}
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 = qemu_mallocz(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 = qemu_mallocz(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:
qemu_free(s);
return NULL;
}
QEMUFile *qemu_fopen_socket(int fd)
{
QEMUFileSocket *s = qemu_mallocz(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);
fwrite(buf, 1, size, s->stdio_file);
return size;
}
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_fdopen: Argument validity check failed\n");
return NULL;
}
s = qemu_mallocz(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:
qemu_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 = qemu_mallocz(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_has_error(QEMUFile *f)
{
return f->has_error;
}
void qemu_file_set_error(QEMUFile *f)
{
f->has_error = 1;
}
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
f->has_error = 1;
f->buf_index = 0;
}
}
static void qemu_fill_buffer(QEMUFile *f)
{
int len;
if (!f->get_buffer)
return;
if (f->is_write)
abort();
len = f->get_buffer(f->opaque, f->buf, f->buf_offset, IO_BUF_SIZE);
if (len > 0) {
f->buf_index = 0;
f->buf_size = len;
f->buf_offset += len;
} else if (len != -EAGAIN)
f->has_error = 1;
}
int qemu_fclose(QEMUFile *f)
{
int ret = 0;
qemu_fflush(f);
if (f->close)
ret = f->close(f->opaque);
qemu_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->has_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->has_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->has_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);
}
int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size1)
{
int size, l;
if (f->is_write)
abort();
size = size1;
while (size > 0) {
l = f->buf_size - f->buf_index;
if (l == 0) {
qemu_fill_buffer(f);
l = f->buf_size - f->buf_index;
if (l == 0)
break;
}
if (l > size)
l = size;
memcpy(buf, f->buf + f->buf_index, l);
f->buf_index += l;
buf += l;
size -= l;
}
return size1 - size;
}
int qemu_get_byte(QEMUFile *f)
{
if (f->is_write)
abort();
if (f->buf_index >= f->buf_size) {
qemu_fill_buffer(f);
if (f->buf_index >= f->buf_size)
return 0;
}
return f->buf[f->buf_index++];
}
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;
}
size_t qemu_file_get_rate_limit(QEMUFile *f)
{
if (f->get_rate_limit)
return f->get_rate_limit(f->opaque);
return 0;
}
size_t qemu_file_set_rate_limit(QEMUFile *f, size_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;
}
/* 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,
};
/* 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 usefull anymore */
static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
qemu_fseek(f, size, SEEK_CUR);
return 0;
}
static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
qemu_fseek(f, size, SEEK_CUR);
}
const VMStateInfo vmstate_info_unused_buffer = {
.name = "unused_buffer",
.get = get_unused_buffer,
.put = put_unused_buffer,
};
typedef struct SaveStateEntry {
QTAILQ_ENTRY(SaveStateEntry) entry;
char idstr[256];
int instance_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;
} 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;
}
/* 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(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 = qemu_mallocz(sizeof(SaveStateEntry));
pstrcpy(se->idstr, sizeof(se->idstr), idstr);
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;
if (instance_id == -1) {
se->instance_id = calculate_new_instance_id(idstr);
} else {
se->instance_id = instance_id;
}
/* add at the end of list */
QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
return 0;
}
int register_savevm(const char *idstr,
int instance_id,
int version_id,
SaveStateHandler *save_state,
LoadStateHandler *load_state,
void *opaque)
{
return register_savevm_live(idstr, instance_id, version_id,
NULL, NULL, save_state, load_state, opaque);
}
void unregister_savevm(const char *idstr, void *opaque)
{
SaveStateEntry *se, *new_se;
QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
if (strcmp(se->idstr, idstr) == 0 && se->opaque == opaque) {
QTAILQ_REMOVE(&savevm_handlers, se, entry);
qemu_free(se);
}
}
}
int vmstate_register(int instance_id, const VMStateDescription *vmsd,
void *opaque)
{
SaveStateEntry *se;
se = qemu_mallocz(sizeof(SaveStateEntry));
pstrcpy(se->idstr, sizeof(se->idstr), vmsd->name);
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;
if (instance_id == -1) {
se->instance_id = calculate_new_instance_id(vmsd->name);
} else {
se->instance_id = instance_id;
}
/* add at the end of list */
QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
return 0;
}
void vmstate_unregister(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);
qemu_free(se);
}
}
}
int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque, int version_id)
{
VMStateField *field = vmsd->fields;
if (version_id > vmsd->version_id) {
return -EINVAL;
}
if (version_id < vmsd->minimum_version_id_old) {
return -EINVAL;
}
if (version_id < vmsd->minimum_version_id) {
return vmsd->load_state_old(f, opaque, version_id);
}
if (vmsd->pre_load) {
int ret = vmsd->pre_load(opaque);
if (ret)
return ret;
}
while(field->name) {
if ((field->field_exists &&
field->field_exists(opaque, version_id)) ||
(!field->field_exists &&
field->version_id <= version_id)) {
void *base_addr = opaque + field->offset;
int ret, i, n_elems = 1;
if (field->flags & VMS_ARRAY) {
n_elems = field->num;
} else if (field->flags & VMS_VARRAY_INT32) {
n_elems = *(int32_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT16) {
n_elems = *(uint16_t *)(opaque+field->num_offset);
}
if (field->flags & VMS_POINTER) {
base_addr = *(void **)base_addr;
}
for (i = 0; i < n_elems; i++) {
void *addr = base_addr + field->size * i;
if (field->flags & VMS_ARRAY_OF_POINTER) {
addr = *(void **)addr;
}
if (field->flags & VMS_STRUCT) {
ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
} else {
ret = field->info->get(f, addr, field->size);
}
if (ret < 0) {
return ret;
}
}
}
field++;
}
if (vmsd->post_load) {
return vmsd->post_load(opaque, version_id);
}
return 0;
}
void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque)
{
VMStateField *field = vmsd->fields;
if (vmsd->pre_save) {
vmsd->pre_save(opaque);
}
while(field->name) {
if (!field->field_exists ||
field->field_exists(opaque, vmsd->version_id)) {
void *base_addr = opaque + field->offset;
int i, n_elems = 1;
if (field->flags & VMS_ARRAY) {
n_elems = field->num;
} else if (field->flags & VMS_VARRAY_INT32) {
n_elems = *(int32_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT16) {
n_elems = *(uint16_t *)(opaque+field->num_offset);
}
if (field->flags & VMS_POINTER) {
base_addr = *(void **)base_addr;
}
for (i = 0; i < n_elems; i++) {
void *addr = base_addr + field->size * i;
if (field->flags & VMS_STRUCT) {
vmstate_save_state(f, field->vmsd, addr);
} else {
field->info->put(f, addr, field->size);
}
}
}
field++;
}
if (vmsd->post_save) {
vmsd->post_save(opaque);
}
}
static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
{
if (!se->vmsd) { /* Old style */
return se->load_state(f, se->opaque, version_id);
}
return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
}
static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
{
if (!se->vmsd) { /* Old style */
se->save_state(f, se->opaque);
return;
}
vmstate_save_state(f,se->vmsd, se->opaque);
}
#define QEMU_VM_FILE_MAGIC 0x5145564d
#define QEMU_VM_FILE_VERSION_COMPAT 0x00000002
#define QEMU_VM_FILE_VERSION 0x00000003
#define QEMU_VM_EOF 0x00
#define QEMU_VM_SECTION_START 0x01
#define QEMU_VM_SECTION_PART 0x02
#define QEMU_VM_SECTION_END 0x03
#define QEMU_VM_SECTION_FULL 0x04
int qemu_savevm_state_begin(QEMUFile *f, int blk_enable, int shared)
{
SaveStateEntry *se;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if(se->set_params == NULL) {
continue;
}
se->set_params(blk_enable, shared, se->opaque);
}
qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
qemu_put_be32(f, QEMU_VM_FILE_VERSION);
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
int len;
if (se->save_live_state == NULL)
continue;
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_START);
qemu_put_be32(f, se->section_id);
/* ID string */
len = strlen(se->idstr);
qemu_put_byte(f, len);
qemu_put_buffer(f, (uint8_t *)se->idstr, len);
qemu_put_be32(f, se->instance_id);
qemu_put_be32(f, se->version_id);
se->save_live_state(f, QEMU_VM_SECTION_START, se->opaque);
}
if (qemu_file_has_error(f))
return -EIO;
return 0;
}
int qemu_savevm_state_iterate(QEMUFile *f)
{
SaveStateEntry *se;
int ret = 1;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (se->save_live_state == NULL)
continue;
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_PART);
qemu_put_be32(f, se->section_id);
ret &= !!se->save_live_state(f, QEMU_VM_SECTION_PART, se->opaque);
}
if (ret)
return 1;
if (qemu_file_has_error(f))
return -EIO;
return 0;
}
int qemu_savevm_state_complete(QEMUFile *f)
{
SaveStateEntry *se;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (se->save_live_state == NULL)
continue;
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_END);
qemu_put_be32(f, se->section_id);
se->save_live_state(f, QEMU_VM_SECTION_END, se->opaque);
}
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
int len;
if (se->save_state == NULL && se->vmsd == NULL)
continue;
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_FULL);
qemu_put_be32(f, se->section_id);
/* ID string */
len = strlen(se->idstr);
qemu_put_byte(f, len);
qemu_put_buffer(f, (uint8_t *)se->idstr, len);
qemu_put_be32(f, se->instance_id);
qemu_put_be32(f, se->version_id);
vmstate_save(f, se);
}
qemu_put_byte(f, QEMU_VM_EOF);
if (qemu_file_has_error(f))
return -EIO;
return 0;
}
int qemu_savevm_state(QEMUFile *f)
{
int saved_vm_running;
int ret;
saved_vm_running = vm_running;
vm_stop(0);
bdrv_flush_all();
ret = qemu_savevm_state_begin(f, 0, 0);
if (ret < 0)
goto out;
do {
ret = qemu_savevm_state_iterate(f);
if (ret < 0)
goto out;
} while (ret == 0);
ret = qemu_savevm_state_complete(f);
out:
if (qemu_file_has_error(f))
ret = -EIO;
if (!ret && saved_vm_running)
vm_start();
return ret;
}
static SaveStateEntry *find_se(const char *idstr, int instance_id)
{
SaveStateEntry *se;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!strcmp(se->idstr, idstr) &&
instance_id == se->instance_id)
return se;
}
return NULL;
}
typedef struct LoadStateEntry {
QLIST_ENTRY(LoadStateEntry) entry;
SaveStateEntry *se;
int section_id;
int version_id;
} LoadStateEntry;
int qemu_loadvm_state(QEMUFile *f)
{
QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
QLIST_HEAD_INITIALIZER(loadvm_handlers);
LoadStateEntry *le, *new_le;
uint8_t section_type;
unsigned int v;
int ret;
v = qemu_get_be32(f);
if (v != QEMU_VM_FILE_MAGIC)
return -EINVAL;
v = qemu_get_be32(f);
if (v == QEMU_VM_FILE_VERSION_COMPAT) {
fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
return -ENOTSUP;
}
if (v != QEMU_VM_FILE_VERSION)
return -ENOTSUP;
while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
uint32_t instance_id, version_id, section_id;
SaveStateEntry *se;
char idstr[257];
int len;
switch (section_type) {
case QEMU_VM_SECTION_START:
case QEMU_VM_SECTION_FULL:
/* Read section start */
section_id = qemu_get_be32(f);
len = qemu_get_byte(f);
qemu_get_buffer(f, (uint8_t *)idstr, len);
idstr[len] = 0;
instance_id = qemu_get_be32(f);
version_id = qemu_get_be32(f);
/* Find savevm section */
se = find_se(idstr, instance_id);
if (se == NULL) {
fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
ret = -EINVAL;
goto out;
}
/* Validate version */
if (version_id > se->version_id) {
fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
version_id, idstr, se->version_id);
ret = -EINVAL;
goto out;
}
/* Add entry */
le = qemu_mallocz(sizeof(*le));
le->se = se;
le->section_id = section_id;
le->version_id = version_id;
QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
ret = vmstate_load(f, le->se, le->version_id);
if (ret < 0) {
fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
instance_id, idstr);
goto out;
}
break;
case QEMU_VM_SECTION_PART:
case QEMU_VM_SECTION_END:
section_id = qemu_get_be32(f);
QLIST_FOREACH(le, &loadvm_handlers, entry) {
if (le->section_id == section_id) {
break;
}
}
if (le == NULL) {
fprintf(stderr, "Unknown savevm section %d\n", section_id);
ret = -EINVAL;
goto out;
}
ret = vmstate_load(f, le->se, le->version_id);
if (ret < 0) {
fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
section_id);
goto out;
}
break;
default:
fprintf(stderr, "Unknown savevm section type %d\n", section_type);
ret = -EINVAL;
goto out;
}
}
ret = 0;
out:
QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
QLIST_REMOVE(le, entry);
qemu_free(le);
}
if (qemu_file_has_error(f))
ret = -EIO;
return ret;
}
/* device can contain snapshots */
static int bdrv_can_snapshot(BlockDriverState *bs)
{
return (bs &&
!bdrv_is_removable(bs) &&
!bdrv_is_read_only(bs));
}
/* device must be snapshots in order to have a reliable snapshot */
static int bdrv_has_snapshot(BlockDriverState *bs)
{
return (bs &&
!bdrv_is_removable(bs) &&
!bdrv_is_read_only(bs));
}
static BlockDriverState *get_bs_snapshots(void)
{
BlockDriverState *bs;
DriveInfo *dinfo;
if (bs_snapshots)
return bs_snapshots;
QTAILQ_FOREACH(dinfo, &drives, next) {
bs = dinfo->bdrv;
if (bdrv_can_snapshot(bs))
goto ok;
}
return NULL;
ok:
bs_snapshots = bs;
return bs;
}
static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
const char *name)
{
QEMUSnapshotInfo *sn_tab, *sn;
int nb_sns, i, ret;
ret = -ENOENT;
nb_sns = bdrv_snapshot_list(bs, &sn_tab);
if (nb_sns < 0)
return ret;
for(i = 0; i < nb_sns; i++) {
sn = &sn_tab[i];
if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
*sn_info = *sn;
ret = 0;
break;
}
}
qemu_free(sn_tab);
return ret;
}
/*
* Deletes snapshots of a given name in all opened images.
*/
static int del_existing_snapshots(Monitor *mon, const char *name)
{
BlockDriverState *bs;
DriveInfo *dinfo;
QEMUSnapshotInfo sn1, *snapshot = &sn1;
int ret;
QTAILQ_FOREACH(dinfo, &drives, next) {
bs = dinfo->bdrv;
if (bdrv_can_snapshot(bs) &&
bdrv_snapshot_find(bs, snapshot, name) >= 0)
{
ret = bdrv_snapshot_delete(bs, name);
if (ret < 0) {
monitor_printf(mon,
"Error while deleting snapshot on '%s'\n",
bdrv_get_device_name(bs));
return -1;
}
}
}
return 0;
}
void do_savevm(Monitor *mon, const QDict *qdict)
{
DriveInfo *dinfo;
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
int ret;
QEMUFile *f;
int saved_vm_running;
uint32_t vm_state_size;
#ifdef _WIN32
struct _timeb tb;
#else
struct timeval tv;
#endif
const char *name = qdict_get_try_str(qdict, "name");
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No block device can accept snapshots\n");
return;
}
/* ??? Should this occur after vm_stop? */
qemu_aio_flush();
saved_vm_running = vm_running;
vm_stop(0);
memset(sn, 0, sizeof(*sn));
if (name) {
ret = bdrv_snapshot_find(bs, old_sn, name);
if (ret >= 0) {
pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
} else {
pstrcpy(sn->name, sizeof(sn->name), name);
}
}
/* fill auxiliary fields */
#ifdef _WIN32
_ftime(&tb);
sn->date_sec = tb.time;
sn->date_nsec = tb.millitm * 1000000;
#else
gettimeofday(&tv, NULL);
sn->date_sec = tv.tv_sec;
sn->date_nsec = tv.tv_usec * 1000;
#endif
sn->vm_clock_nsec = qemu_get_clock(vm_clock);
/* Delete old snapshots of the same name */
if (del_existing_snapshots(mon, name) < 0) {
goto the_end;
}
/* save the VM state */
f = qemu_fopen_bdrv(bs, 1);
if (!f) {
monitor_printf(mon, "Could not open VM state file\n");
goto the_end;
}
ret = qemu_savevm_state(f);
vm_state_size = qemu_ftell(f);
qemu_fclose(f);
if (ret < 0) {
monitor_printf(mon, "Error %d while writing VM\n", ret);
goto the_end;
}
/* create the snapshots */
QTAILQ_FOREACH(dinfo, &drives, next) {
bs1 = dinfo->bdrv;
if (bdrv_has_snapshot(bs1)) {
/* Write VM state size only to the image that contains the state */
sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
ret = bdrv_snapshot_create(bs1, sn);
if (ret < 0) {
monitor_printf(mon, "Error while creating snapshot on '%s'\n",
bdrv_get_device_name(bs1));
}
}
}
the_end:
if (saved_vm_running)
vm_start();
}
int load_vmstate(Monitor *mon, const char *name)
{
DriveInfo *dinfo;
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo sn;
QEMUFile *f;
int ret;
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No block device supports snapshots\n");
return -EINVAL;
}
/* Flush all IO requests so they don't interfere with the new state. */
qemu_aio_flush();
QTAILQ_FOREACH(dinfo, &drives, next) {
bs1 = dinfo->bdrv;
if (bdrv_has_snapshot(bs1)) {
ret = bdrv_snapshot_goto(bs1, name);
if (ret < 0) {
if (bs != bs1)
monitor_printf(mon, "Warning: ");
switch(ret) {
case -ENOTSUP:
monitor_printf(mon,
"Snapshots not supported on device '%s'\n",
bdrv_get_device_name(bs1));
break;
case -ENOENT:
monitor_printf(mon, "Could not find snapshot '%s' on "
"device '%s'\n",
name, bdrv_get_device_name(bs1));
break;
default:
monitor_printf(mon, "Error %d while activating snapshot on"
" '%s'\n", ret, bdrv_get_device_name(bs1));
break;
}
/* fatal on snapshot block device */
if (bs == bs1)
return 0;
}
}
}
/* Don't even try to load empty VM states */
ret = bdrv_snapshot_find(bs, &sn, name);
if ((ret >= 0) && (sn.vm_state_size == 0))
return -EINVAL;
/* restore the VM state */
f = qemu_fopen_bdrv(bs, 0);
if (!f) {
monitor_printf(mon, "Could not open VM state file\n");
return -EINVAL;
}
ret = qemu_loadvm_state(f);
qemu_fclose(f);
if (ret < 0) {
monitor_printf(mon, "Error %d while loading VM state\n", ret);
return ret;
}
return 0;
}
void do_delvm(Monitor *mon, const QDict *qdict)
{
DriveInfo *dinfo;
BlockDriverState *bs, *bs1;
int ret;
const char *name = qdict_get_str(qdict, "name");
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No block device supports snapshots\n");
return;
}
QTAILQ_FOREACH(dinfo, &drives, next) {
bs1 = dinfo->bdrv;
if (bdrv_has_snapshot(bs1)) {
ret = bdrv_snapshot_delete(bs1, name);
if (ret < 0) {
if (ret == -ENOTSUP)
monitor_printf(mon,
"Snapshots not supported on device '%s'\n",
bdrv_get_device_name(bs1));
else
monitor_printf(mon, "Error %d while deleting snapshot on "
"'%s'\n", ret, bdrv_get_device_name(bs1));
}
}
}
}
void do_info_snapshots(Monitor *mon)
{
DriveInfo *dinfo;
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo *sn_tab, *sn;
int nb_sns, i;
char buf[256];
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No available block device supports snapshots\n");
return;
}
monitor_printf(mon, "Snapshot devices:");
QTAILQ_FOREACH(dinfo, &drives, next) {
bs1 = dinfo->bdrv;
if (bdrv_has_snapshot(bs1)) {
if (bs == bs1)
monitor_printf(mon, " %s", bdrv_get_device_name(bs1));
}
}
monitor_printf(mon, "\n");
nb_sns = bdrv_snapshot_list(bs, &sn_tab);
if (nb_sns < 0) {
monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
return;
}
monitor_printf(mon, "Snapshot list (from %s):\n",
bdrv_get_device_name(bs));
monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
for(i = 0; i < nb_sns; i++) {
sn = &sn_tab[i];
monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
}
qemu_free(sn_tab);
}
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