qemu/savevm.c
Stefan Hajnoczi d7cd369402 migration: restrict scope of incoming fd read handler
The incoming migration is processed in a coroutine and uses an fd read
handler to enter the yielded coroutine when data becomes available.

The read handler was set too broadly, so that spurious coroutine entries
were be triggered if other coroutine users yielded (like the block
layer's bdrv_write() function).

Install the fd read only only when yielding for more data to become
available.  This prevents spurious coroutine entries which break code
that assumes only a specific set of places can re-enter the coroutine.

This patch fixes crashes in block/raw-posix.c that are triggered with
"migrate -b" when qiov becomes a dangling pointer due to a spurious
coroutine entry that frees qiov early.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1360598505-5512-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11 13:22:52 -06:00

2417 lines
59 KiB
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 "config-host.h"
#include "qemu-common.h"
#include "hw/hw.h"
#include "hw/qdev.h"
#include "net/net.h"
#include "monitor/monitor.h"
#include "sysemu/sysemu.h"
#include "qemu/timer.h"
#include "audio/audio.h"
#include "migration/migration.h"
#include "qemu/sockets.h"
#include "qemu/queue.h"
#include "sysemu/cpus.h"
#include "exec/memory.h"
#include "qmp-commands.h"
#include "trace.h"
#include "qemu/bitops.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(qemu_get_queue(nic), 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 {
const QEMUFileOps *ops;
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;
typedef struct {
Coroutine *co;
int fd;
} FDYieldUntilData;
static void fd_coroutine_enter(void *opaque)
{
FDYieldUntilData *data = opaque;
qemu_set_fd_handler(data->fd, NULL, NULL, NULL);
qemu_coroutine_enter(data->co, NULL);
}
/**
* Yield until a file descriptor becomes readable
*
* Note that this function clobbers the handlers for the file descriptor.
*/
static void coroutine_fn yield_until_fd_readable(int fd)
{
FDYieldUntilData data;
assert(qemu_in_coroutine());
data.co = qemu_coroutine_self();
data.fd = fd;
qemu_set_fd_handler(fd, fd_coroutine_enter, NULL, &data);
qemu_coroutine_yield();
}
static int socket_get_fd(void *opaque)
{
QEMUFileSocket *s = opaque;
return s->fd;
}
static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
QEMUFileSocket *s = opaque;
ssize_t len;
for (;;) {
len = qemu_recv(s->fd, buf, size, 0);
if (len != -1) {
break;
}
if (socket_error() == EAGAIN) {
yield_until_fd_readable(s->fd);
} else if (socket_error() != EINTR) {
break;
}
}
if (len == -1) {
len = -socket_error();
}
return len;
}
static int socket_close(void *opaque)
{
QEMUFileSocket *s = opaque;
closesocket(s->fd);
g_free(s);
return 0;
}
static int stdio_get_fd(void *opaque)
{
QEMUFileStdio *s = opaque;
return fileno(s->stdio_file);
}
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;
for (;;) {
clearerr(fp);
bytes = fread(buf, 1, size, fp);
if (bytes != 0 || !ferror(fp)) {
break;
}
if (errno == EAGAIN) {
yield_until_fd_readable(fileno(fp));
} else if (errno != EINTR) {
break;
}
}
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;
}
static const QEMUFileOps stdio_pipe_read_ops = {
.get_fd = stdio_get_fd,
.get_buffer = stdio_get_buffer,
.close = stdio_pclose
};
static const QEMUFileOps stdio_pipe_write_ops = {
.get_fd = stdio_get_fd,
.put_buffer = stdio_put_buffer,
.close = stdio_pclose
};
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, &stdio_pipe_read_ops);
} else {
s->file = qemu_fopen_ops(s, &stdio_pipe_write_ops);
}
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);
}
static const QEMUFileOps stdio_file_read_ops = {
.get_fd = stdio_get_fd,
.get_buffer = stdio_get_buffer,
.close = stdio_fclose
};
static const QEMUFileOps stdio_file_write_ops = {
.get_fd = stdio_get_fd,
.put_buffer = stdio_put_buffer,
.close = stdio_fclose
};
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, &stdio_file_read_ops);
} else {
s->file = qemu_fopen_ops(s, &stdio_file_write_ops);
}
return s->file;
fail:
g_free(s);
return NULL;
}
static const QEMUFileOps socket_read_ops = {
.get_fd = socket_get_fd,
.get_buffer = socket_get_buffer,
.close = socket_close
};
QEMUFile *qemu_fopen_socket(int fd)
{
QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
s->fd = fd;
s->file = qemu_fopen_ops(s, &socket_read_ops);
return s->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, &stdio_file_write_ops);
} else {
s->file = qemu_fopen_ops(s, &stdio_file_read_ops);
}
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 bdrv_flush(opaque);
}
static const QEMUFileOps bdrv_read_ops = {
.get_buffer = block_get_buffer,
.close = bdrv_fclose
};
static const QEMUFileOps bdrv_write_ops = {
.put_buffer = block_put_buffer,
.close = bdrv_fclose
};
static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
{
if (is_writable)
return qemu_fopen_ops(bs, &bdrv_write_ops);
return qemu_fopen_ops(bs, &bdrv_read_ops);
}
QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops)
{
QEMUFile *f;
f = g_malloc0(sizeof(QEMUFile));
f->opaque = opaque;
f->ops = ops;
f->is_write = 0;
return f;
}
int qemu_file_get_error(QEMUFile *f)
{
return f->last_error;
}
static void qemu_file_set_error(QEMUFile *f, int ret)
{
if (f->last_error == 0) {
f->last_error = ret;
}
}
/** Flushes QEMUFile buffer
*
*/
static int qemu_fflush(QEMUFile *f)
{
int ret = 0;
if (!f->ops->put_buffer)
return 0;
if (f->is_write && f->buf_index > 0) {
ret = f->ops->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
if (ret >= 0) {
f->buf_offset += f->buf_index;
}
f->buf_index = 0;
}
return ret;
}
static void qemu_fill_buffer(QEMUFile *f)
{
int len;
int pending;
if (!f->ops->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->ops->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) {
qemu_file_set_error(f, -EIO);
} else if (len != -EAGAIN)
qemu_file_set_error(f, len);
}
int qemu_get_fd(QEMUFile *f)
{
if (f->ops->get_fd) {
return f->ops->get_fd(f->opaque);
}
return -1;
}
/** 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;
ret = qemu_fflush(f);
if (f->ops->close) {
int ret2 = f->ops->close(f->opaque);
if (ret >= 0) {
ret = ret2;
}
}
/* 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_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
{
int l;
if (f->last_error) {
return;
}
if (f->is_write == 0 && f->buf_index > 0) {
fprintf(stderr,
"Attempted to write to buffer while read buffer is not empty\n");
abort();
}
while (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) {
int ret = qemu_fflush(f);
if (ret < 0) {
qemu_file_set_error(f, ret);
break;
}
}
}
}
void qemu_put_byte(QEMUFile *f, int v)
{
if (f->last_error) {
return;
}
if (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) {
int ret = qemu_fflush(f);
if (ret < 0) {
qemu_file_set_error(f, ret);
}
}
}
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;
}
static int64_t qemu_ftell(QEMUFile *f)
{
return f->buf_offset - f->buf_size + f->buf_index;
}
int qemu_file_rate_limit(QEMUFile *f)
{
if (f->ops->rate_limit)
return f->ops->rate_limit(f->opaque);
return 0;
}
int64_t qemu_file_get_rate_limit(QEMUFile *f)
{
if (f->ops->get_rate_limit)
return f->ops->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->ops->set_rate_limit)
return f->ops->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,
};
/* bitmaps (as defined by bitmap.h). Note that size here is the size
* of the bitmap in bits. The on-the-wire format of a bitmap is 64
* bit words with the bits in big endian order. The in-memory format
* is an array of 'unsigned long', which may be either 32 or 64 bits.
*/
/* This is the number of 64 bit words sent over the wire */
#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, 64)
static int get_bitmap(QEMUFile *f, void *pv, size_t size)
{
unsigned long *bmp = pv;
int i, idx = 0;
for (i = 0; i < BITS_TO_U64S(size); i++) {
uint64_t w = qemu_get_be64(f);
bmp[idx++] = w;
if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
bmp[idx++] = w >> 32;
}
}
return 0;
}
static void put_bitmap(QEMUFile *f, void *pv, size_t size)
{
unsigned long *bmp = pv;
int i, idx = 0;
for (i = 0; i < BITS_TO_U64S(size); i++) {
uint64_t w = bmp[idx++];
if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
w |= ((uint64_t)bmp[idx++]) << 32;
}
qemu_put_be64(f, w);
}
}
const VMStateInfo vmstate_info_bitmap = {
.name = "bitmap",
.get = get_bitmap,
.put = put_bitmap,
};
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;
SaveVMHandlers *ops;
const VMStateDescription *vmsd;
void *opaque;
CompatEntry *compat;
int no_migrate;
int is_ram;
} 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,
SaveVMHandlers *ops,
void *opaque)
{
SaveStateEntry *se;
se = g_malloc0(sizeof(SaveStateEntry));
se->version_id = version_id;
se->section_id = global_section_id++;
se->ops = ops;
se->opaque = opaque;
se->vmsd = NULL;
se->no_migrate = 0;
/* if this is a live_savem then set is_ram */
if (ops->save_live_setup != NULL) {
se->is_ram = 1;
}
if (dev) {
char *id = qdev_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)
{
SaveVMHandlers *ops = g_malloc0(sizeof(SaveVMHandlers));
ops->save_state = save_state;
ops->load_state = load_state;
return register_savevm_live(dev, idstr, instance_id, version_id,
ops, opaque);
}
void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
{
SaveStateEntry *se, *new_se;
char id[256] = "";
if (dev) {
char *path = qdev_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->ops);
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->opaque = opaque;
se->vmsd = vmsd;
se->alias_id = alias_id;
se->no_migrate = vmsd->unmigratable;
if (dev) {
char *id = qdev_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);
}
}
}
static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque);
static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque);
int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque, int version_id)
{
VMStateField *field = vmsd->fields;
int ret;
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 i, n_elems = 1;
int size = field->size;
if (field->flags & VMS_VBUFFER) {
size = *(int32_t *)(opaque+field->size_offset);
if (field->flags & VMS_MULTIPLY) {
size *= field->size;
}
}
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_UINT32) {
n_elems = *(uint32_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT16) {
n_elems = *(uint16_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT8) {
n_elems = *(uint8_t *)(opaque+field->num_offset);
}
if (field->flags & VMS_POINTER) {
base_addr = *(void **)base_addr + field->start;
}
for (i = 0; i < n_elems; i++) {
void *addr = base_addr + 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, size);
}
if (ret < 0) {
return ret;
}
}
}
field++;
}
ret = vmstate_subsection_load(f, vmsd, opaque);
if (ret != 0) {
return ret;
}
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;
int size = field->size;
if (field->flags & VMS_VBUFFER) {
size = *(int32_t *)(opaque+field->size_offset);
if (field->flags & VMS_MULTIPLY) {
size *= field->size;
}
}
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_UINT32) {
n_elems = *(uint32_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT16) {
n_elems = *(uint16_t *)(opaque+field->num_offset);
} else if (field->flags & VMS_VARRAY_UINT8) {
n_elems = *(uint8_t *)(opaque+field->num_offset);
}
if (field->flags & VMS_POINTER) {
base_addr = *(void **)base_addr + field->start;
}
for (i = 0; i < n_elems; i++) {
void *addr = base_addr + size * i;
if (field->flags & VMS_ARRAY_OF_POINTER) {
addr = *(void **)addr;
}
if (field->flags & VMS_STRUCT) {
vmstate_save_state(f, field->vmsd, addr);
} else {
field->info->put(f, addr, size);
}
}
}
field++;
}
vmstate_subsection_save(f, vmsd, opaque);
}
static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
{
if (!se->vmsd) { /* Old style */
return se->ops->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->ops->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
#define QEMU_VM_SUBSECTION 0x05
bool qemu_savevm_state_blocked(Error **errp)
{
SaveStateEntry *se;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (se->no_migrate) {
error_set(errp, QERR_MIGRATION_NOT_SUPPORTED, se->idstr);
return true;
}
}
return false;
}
int qemu_savevm_state_begin(QEMUFile *f,
const MigrationParams *params)
{
SaveStateEntry *se;
int ret;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->set_params) {
continue;
}
se->ops->set_params(params, 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->ops || !se->ops->save_live_setup) {
continue;
}
if (se->ops && se->ops->is_active) {
if (!se->ops->is_active(se->opaque)) {
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);
ret = se->ops->save_live_setup(f, se->opaque);
if (ret < 0) {
qemu_savevm_state_cancel();
return ret;
}
}
ret = qemu_file_get_error(f);
if (ret != 0) {
qemu_savevm_state_cancel();
}
return ret;
}
/*
* this function has three return values:
* negative: there was one error, and we have -errno.
* 0 : We haven't finished, caller have to go again
* 1 : We have finished, we can go to complete phase
*/
int qemu_savevm_state_iterate(QEMUFile *f)
{
SaveStateEntry *se;
int ret = 1;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_iterate) {
continue;
}
if (se->ops && se->ops->is_active) {
if (!se->ops->is_active(se->opaque)) {
continue;
}
}
if (qemu_file_rate_limit(f)) {
return 0;
}
trace_savevm_section_start();
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_PART);
qemu_put_be32(f, se->section_id);
ret = se->ops->save_live_iterate(f, se->opaque);
trace_savevm_section_end(se->section_id);
if (ret <= 0) {
/* Do not proceed to the next vmstate before this one reported
completion of the current stage. This serializes the migration
and reduces the probability that a faster changing state is
synchronized over and over again. */
break;
}
}
if (ret != 0) {
return ret;
}
ret = qemu_file_get_error(f);
if (ret != 0) {
qemu_savevm_state_cancel();
}
return ret;
}
int qemu_savevm_state_complete(QEMUFile *f)
{
SaveStateEntry *se;
int ret;
cpu_synchronize_all_states();
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_complete) {
continue;
}
if (se->ops && se->ops->is_active) {
if (!se->ops->is_active(se->opaque)) {
continue;
}
}
trace_savevm_section_start();
/* Section type */
qemu_put_byte(f, QEMU_VM_SECTION_END);
qemu_put_be32(f, se->section_id);
ret = se->ops->save_live_complete(f, se->opaque);
trace_savevm_section_end(se->section_id);
if (ret < 0) {
return ret;
}
}
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
int len;
if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
continue;
}
trace_savevm_section_start();
/* 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);
trace_savevm_section_end(se->section_id);
}
qemu_put_byte(f, QEMU_VM_EOF);
return qemu_file_get_error(f);
}
uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size)
{
SaveStateEntry *se;
uint64_t ret = 0;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (!se->ops || !se->ops->save_live_pending) {
continue;
}
if (se->ops && se->ops->is_active) {
if (!se->ops->is_active(se->opaque)) {
continue;
}
}
ret += se->ops->save_live_pending(f, se->opaque, max_size);
}
return ret;
}
void qemu_savevm_state_cancel(void)
{
SaveStateEntry *se;
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
if (se->ops && se->ops->cancel) {
se->ops->cancel(se->opaque);
}
}
}
static int qemu_savevm_state(QEMUFile *f)
{
int ret;
MigrationParams params = {
.blk = 0,
.shared = 0
};
if (qemu_savevm_state_blocked(NULL)) {
ret = -EINVAL;
goto out;
}
ret = qemu_savevm_state_begin(f, &params);
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 (ret == 0) {
ret = qemu_file_get_error(f);
}
return ret;
}
static int qemu_save_device_state(QEMUFile *f)
{
SaveStateEntry *se;
qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
qemu_put_be32(f, QEMU_VM_FILE_VERSION);
cpu_synchronize_all_states();
QTAILQ_FOREACH(se, &savevm_handlers, entry) {
int len;
if (se->is_ram) {
continue;
}
if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
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);
return qemu_file_get_error(f);
}
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 ||
instance_id == se->alias_id))
return se;
/* Migrating from an older version? */
if (strstr(se->idstr, idstr) && se->compat) {
if (!strcmp(se->compat->idstr, idstr) &&
(instance_id == se->compat->instance_id ||
instance_id == se->alias_id))
return se;
}
}
return NULL;
}
static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
{
while(sub && sub->needed) {
if (strcmp(idstr, sub->vmsd->name) == 0) {
return sub->vmsd;
}
sub++;
}
return NULL;
}
static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque)
{
while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
char idstr[256];
int ret;
uint8_t version_id, len, size;
const VMStateDescription *sub_vmsd;
len = qemu_peek_byte(f, 1);
if (len < strlen(vmsd->name) + 1) {
/* subsection name has be be "section_name/a" */
return 0;
}
size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
if (size != len) {
return 0;
}
idstr[size] = 0;
if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
/* it don't have a valid subsection name */
return 0;
}
sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
if (sub_vmsd == NULL) {
return -ENOENT;
}
qemu_file_skip(f, 1); /* subsection */
qemu_file_skip(f, 1); /* len */
qemu_file_skip(f, len); /* idstr */
version_id = qemu_get_be32(f);
ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
if (ret) {
return ret;
}
}
return 0;
}
static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
void *opaque)
{
const VMStateSubsection *sub = vmsd->subsections;
while (sub && sub->needed) {
if (sub->needed(opaque)) {
const VMStateDescription *vmsd = sub->vmsd;
uint8_t len;
qemu_put_byte(f, QEMU_VM_SUBSECTION);
len = strlen(vmsd->name);
qemu_put_byte(f, len);
qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
qemu_put_be32(f, vmsd->version_id);
vmstate_save_state(f, vmsd, opaque);
}
sub++;
}
}
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;
if (qemu_savevm_state_blocked(NULL)) {
return -EINVAL;
}
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 = g_malloc0(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;
}
}
cpu_synchronize_all_post_init();
ret = 0;
out:
QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
QLIST_REMOVE(le, entry);
g_free(le);
}
if (ret == 0) {
ret = qemu_file_get_error(f);
}
return ret;
}
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;
}
}
g_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;
QEMUSnapshotInfo sn1, *snapshot = &sn1;
int ret;
bs = NULL;
while ((bs = bdrv_next(bs))) {
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)
{
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
int ret;
QEMUFile *f;
int saved_vm_running;
uint64_t vm_state_size;
qemu_timeval tv;
struct tm tm;
const char *name = qdict_get_try_str(qdict, "name");
/* Verify if there is a device that doesn't support snapshots and is writable */
bs = NULL;
while ((bs = bdrv_next(bs))) {
if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
continue;
}
if (!bdrv_can_snapshot(bs)) {
monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
bdrv_get_device_name(bs));
return;
}
}
bs = bdrv_snapshots();
if (!bs) {
monitor_printf(mon, "No block device can accept snapshots\n");
return;
}
saved_vm_running = runstate_is_running();
vm_stop(RUN_STATE_SAVE_VM);
memset(sn, 0, sizeof(*sn));
/* fill auxiliary fields */
qemu_gettimeofday(&tv);
sn->date_sec = tv.tv_sec;
sn->date_nsec = tv.tv_usec * 1000;
sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
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);
}
} else {
/* cast below needed for OpenBSD where tv_sec is still 'long' */
localtime_r((const time_t *)&tv.tv_sec, &tm);
strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
}
/* Delete old snapshots of the same name */
if (name && 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 */
bs1 = NULL;
while ((bs1 = bdrv_next(bs1))) {
if (bdrv_can_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();
}
void qmp_xen_save_devices_state(const char *filename, Error **errp)
{
QEMUFile *f;
int saved_vm_running;
int ret;
saved_vm_running = runstate_is_running();
vm_stop(RUN_STATE_SAVE_VM);
f = qemu_fopen(filename, "wb");
if (!f) {
error_set(errp, QERR_OPEN_FILE_FAILED, filename);
goto the_end;
}
ret = qemu_save_device_state(f);
qemu_fclose(f);
if (ret < 0) {
error_set(errp, QERR_IO_ERROR);
}
the_end:
if (saved_vm_running)
vm_start();
}
int load_vmstate(const char *name)
{
BlockDriverState *bs, *bs_vm_state;
QEMUSnapshotInfo sn;
QEMUFile *f;
int ret;
bs_vm_state = bdrv_snapshots();
if (!bs_vm_state) {
error_report("No block device supports snapshots");
return -ENOTSUP;
}
/* Don't even try to load empty VM states */
ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
if (ret < 0) {
return ret;
} else if (sn.vm_state_size == 0) {
error_report("This is a disk-only snapshot. Revert to it offline "
"using qemu-img.");
return -EINVAL;
}
/* Verify if there is any device that doesn't support snapshots and is
writable and check if the requested snapshot is available too. */
bs = NULL;
while ((bs = bdrv_next(bs))) {
if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
continue;
}
if (!bdrv_can_snapshot(bs)) {
error_report("Device '%s' is writable but does not support snapshots.",
bdrv_get_device_name(bs));
return -ENOTSUP;
}
ret = bdrv_snapshot_find(bs, &sn, name);
if (ret < 0) {
error_report("Device '%s' does not have the requested snapshot '%s'",
bdrv_get_device_name(bs), name);
return ret;
}
}
/* Flush all IO requests so they don't interfere with the new state. */
bdrv_drain_all();
bs = NULL;
while ((bs = bdrv_next(bs))) {
if (bdrv_can_snapshot(bs)) {
ret = bdrv_snapshot_goto(bs, name);
if (ret < 0) {
error_report("Error %d while activating snapshot '%s' on '%s'",
ret, name, bdrv_get_device_name(bs));
return ret;
}
}
}
/* restore the VM state */
f = qemu_fopen_bdrv(bs_vm_state, 0);
if (!f) {
error_report("Could not open VM state file");
return -EINVAL;
}
qemu_system_reset(VMRESET_SILENT);
ret = qemu_loadvm_state(f);
qemu_fclose(f);
if (ret < 0) {
error_report("Error %d while loading VM state", ret);
return ret;
}
return 0;
}
void do_delvm(Monitor *mon, const QDict *qdict)
{
BlockDriverState *bs, *bs1;
int ret;
const char *name = qdict_get_str(qdict, "name");
bs = bdrv_snapshots();
if (!bs) {
monitor_printf(mon, "No block device supports snapshots\n");
return;
}
bs1 = NULL;
while ((bs1 = bdrv_next(bs1))) {
if (bdrv_can_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, const QDict *qdict)
{
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
int nb_sns, i, ret, available;
int total;
int *available_snapshots;
char buf[256];
bs = bdrv_snapshots();
if (!bs) {
monitor_printf(mon, "No available block device supports snapshots\n");
return;
}
nb_sns = bdrv_snapshot_list(bs, &sn_tab);
if (nb_sns < 0) {
monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
return;
}
if (nb_sns == 0) {
monitor_printf(mon, "There is no snapshot available.\n");
return;
}
available_snapshots = g_malloc0(sizeof(int) * nb_sns);
total = 0;
for (i = 0; i < nb_sns; i++) {
sn = &sn_tab[i];
available = 1;
bs1 = NULL;
while ((bs1 = bdrv_next(bs1))) {
if (bdrv_can_snapshot(bs1) && bs1 != bs) {
ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
if (ret < 0) {
available = 0;
break;
}
}
}
if (available) {
available_snapshots[total] = i;
total++;
}
}
if (total > 0) {
monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
for (i = 0; i < total; i++) {
sn = &sn_tab[available_snapshots[i]];
monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
}
} else {
monitor_printf(mon, "There is no suitable snapshot available\n");
}
g_free(sn_tab);
g_free(available_snapshots);
}
void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)
{
qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK,
memory_region_name(mr), dev);
}
void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev)
{
/* Nothing do to while the implementation is in RAMBlock */
}
void vmstate_register_ram_global(MemoryRegion *mr)
{
vmstate_register_ram(mr, NULL);
}