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qemu/savevm.c
Uri Lublin 8a67ec4d84 exec-migration: handle EINTR in popen_get_buffer() 
Sometimes, upon interrupt, fread returns with no data, and
the (incoming exec) migration fails.

Fix by retrying on such a case.

Signed-off-by: Uri Lublin <uril@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-13 19:19:25 -05:00

1311 lines
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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 HOST_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>
#if defined(__NetBSD__)
#include <net/if_tap.h>
#endif
#ifdef __linux__
#include <linux/if_tun.h>
#endif
#include <arpa/inet.h>
#include <dirent.h>
#include <netdb.h>
#include <sys/select.h>
#ifdef HOST_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"
/* point to the block driver where the snapshots are managed */
static BlockDriverState *bs_snapshots;
#define SELF_ANNOUNCE_ROUNDS 5
#define ETH_P_EXPERIMENTAL 0x01F1 /* just a number */
//#define ETH_P_EXPERIMENTAL 0x0012 /* make it the size of the packet */
#define EXPERIMENTAL_MAGIC 0xf1f23f4f
static int announce_self_create(uint8_t *buf,
uint8_t *mac_addr)
{
uint32_t magic = EXPERIMENTAL_MAGIC;
uint16_t proto = htons(ETH_P_EXPERIMENTAL);
/* FIXME: should we send a different packet (arp/rarp/ping)? */
memset(buf, 0, 64);
memset(buf, 0xff, 6); /* h_dst */
memcpy(buf + 6, mac_addr, 6); /* h_src */
memcpy(buf + 12, &proto, 2); /* h_proto */
memcpy(buf + 14, &magic, 4); /* magic */
return 64; /* len */
}
static void qemu_announce_self_once(void *opaque)
{
int i, len;
VLANState *vlan;
VLANClientState *vc;
uint8_t buf[256];
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;
for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
vc->receive(vc, buf, len);
}
}
if (count--) {
qemu_mod_timer(timer, qemu_get_clock(rt_clock) + 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;
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 QEMUFilePopen
{
FILE *popen_file;
QEMUFile *file;
} QEMUFilePopen;
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 popen_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
{
QEMUFilePopen *s = opaque;
return fwrite(buf, 1, size, s->popen_file);
}
static int popen_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
QEMUFilePopen *s = opaque;
FILE *fp = s->popen_file;
int bytes;
do {
clearerr(fp);
bytes = fread(buf, 1, size, fp);
} while ((bytes == 0) && ferror(fp) && (errno == EINTR));
return bytes;
}
static int popen_close(void *opaque)
{
QEMUFilePopen *s = opaque;
pclose(s->popen_file);
qemu_free(s);
return 0;
}
QEMUFile *qemu_popen(FILE *popen_file, const char *mode)
{
QEMUFilePopen *s;
if (popen_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(QEMUFilePopen));
s->popen_file = popen_file;
if(mode[0] == 'r') {
s->file = qemu_fopen_ops(s, NULL, popen_get_buffer, popen_close, NULL, NULL);
} else {
s->file = qemu_fopen_ops(s, popen_put_buffer, NULL, popen_close, 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_popen_fd(QEMUFile *f)
{
QEMUFilePopen *p;
int fd;
p = (QEMUFilePopen *)f->opaque;
fd = fileno(p->popen_file);
return fd;
}
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);
return s->file;
}
typedef struct QEMUFileStdio
{
FILE *outfile;
} QEMUFileStdio;
static int file_put_buffer(void *opaque, const uint8_t *buf,
int64_t pos, int size)
{
QEMUFileStdio *s = opaque;
fseek(s->outfile, pos, SEEK_SET);
fwrite(buf, 1, size, s->outfile);
return size;
}
static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
QEMUFileStdio *s = opaque;
fseek(s->outfile, pos, SEEK_SET);
return fread(buf, 1, size, s->outfile);
}
static int file_close(void *opaque)
{
QEMUFileStdio *s = opaque;
fclose(s->outfile);
qemu_free(s);
return 0;
}
QEMUFile *qemu_fopen(const char *filename, const char *mode)
{
QEMUFileStdio *s;
s = qemu_mallocz(sizeof(QEMUFileStdio));
s->outfile = fopen(filename, mode);
if (!s->outfile)
goto fail;
if (!strcmp(mode, "wb"))
return qemu_fopen_ops(s, file_put_buffer, NULL, file_close, NULL, NULL);
else if (!strcmp(mode, "rb"))
return qemu_fopen_ops(s, NULL, file_get_buffer, file_close, NULL, NULL);
fail:
if (s->outfile)
fclose(s->outfile);
qemu_free(s);
return NULL;
}
typedef struct QEMUFileBdrv
{
BlockDriverState *bs;
int64_t base_offset;
} QEMUFileBdrv;
static int block_put_buffer(void *opaque, const uint8_t *buf,
int64_t pos, int size)
{
QEMUFileBdrv *s = opaque;
bdrv_put_buffer(s->bs, buf, s->base_offset + pos, size);
return size;
}
static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
{
QEMUFileBdrv *s = opaque;
return bdrv_get_buffer(s->bs, buf, s->base_offset + pos, size);
}
static int bdrv_fclose(void *opaque)
{
QEMUFileBdrv *s = opaque;
qemu_free(s);
return 0;
}
static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int64_t offset, int is_writable)
{
QEMUFileBdrv *s;
s = qemu_mallocz(sizeof(QEMUFileBdrv));
s->bs = bs;
s->base_offset = offset;
if (is_writable)
return qemu_fopen_ops(s, block_put_buffer, NULL, bdrv_fclose, NULL, NULL);
return qemu_fopen_ops(s, NULL, block_get_buffer, bdrv_fclose, NULL, NULL);
}
QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
QEMUFileGetBufferFunc *get_buffer,
QEMUFileCloseFunc *close,
QEMUFileRateLimit *rate_limit,
QEMUFileSetRateLimit *set_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->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_set_rate_limit(QEMUFile *f, size_t new_rate)
{
if (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;
}
typedef struct SaveStateEntry {
char idstr[256];
int instance_id;
int version_id;
int section_id;
SaveLiveStateHandler *save_live_state;
SaveStateHandler *save_state;
LoadStateHandler *load_state;
void *opaque;
struct SaveStateEntry *next;
} SaveStateEntry;
static SaveStateEntry *first_se;
/* 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,
SaveLiveStateHandler *save_live_state,
SaveStateHandler *save_state,
LoadStateHandler *load_state,
void *opaque)
{
SaveStateEntry *se, **pse;
static int global_section_id;
se = qemu_malloc(sizeof(SaveStateEntry));
pstrcpy(se->idstr, sizeof(se->idstr), idstr);
se->instance_id = (instance_id == -1) ? 0 : instance_id;
se->version_id = version_id;
se->section_id = global_section_id++;
se->save_live_state = save_live_state;
se->save_state = save_state;
se->load_state = load_state;
se->opaque = opaque;
se->next = NULL;
/* add at the end of list */
pse = &first_se;
while (*pse != NULL) {
if (instance_id == -1
&& strcmp(se->idstr, (*pse)->idstr) == 0
&& se->instance_id <= (*pse)->instance_id)
se->instance_id = (*pse)->instance_id + 1;
pse = &(*pse)->next;
}
*pse = se;
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, save_state, load_state, opaque);
}
void unregister_savevm(const char *idstr, void *opaque)
{
SaveStateEntry **pse;
pse = &first_se;
while (*pse != NULL) {
if (strcmp((*pse)->idstr, idstr) == 0 && (*pse)->opaque == opaque) {
SaveStateEntry *next = (*pse)->next;
qemu_free(*pse);
*pse = next;
continue;
}
pse = &(*pse)->next;
}
}
#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)
{
SaveStateEntry *se;
qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
qemu_put_be32(f, QEMU_VM_FILE_VERSION);
for (se = first_se; se != NULL; se = se->next) {
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;
for (se = first_se; se != NULL; se = se->next) {
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;
for (se = first_se; se != NULL; se = se->next) {
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);
}
for(se = first_se; se != NULL; se = se->next) {
int len;
if (se->save_state == 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);
se->save_state(f, se->opaque);
}
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);
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;
for(se = first_se; se != NULL; se = se->next) {
if (!strcmp(se->idstr, idstr) &&
instance_id == se->instance_id)
return se;
}
return NULL;
}
typedef struct LoadStateEntry {
SaveStateEntry *se;
int section_id;
int version_id;
struct LoadStateEntry *next;
} LoadStateEntry;
static int qemu_loadvm_state_v2(QEMUFile *f)
{
SaveStateEntry *se;
int len, ret, instance_id, record_len, version_id;
int64_t total_len, end_pos, cur_pos;
char idstr[256];
total_len = qemu_get_be64(f);
end_pos = total_len + qemu_ftell(f);
for(;;) {
if (qemu_ftell(f) >= end_pos)
break;
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);
record_len = qemu_get_be32(f);
cur_pos = qemu_ftell(f);
se = find_se(idstr, instance_id);
if (!se) {
fprintf(stderr, "qemu: warning: instance 0x%x of device '%s' not present in current VM\n",
instance_id, idstr);
} else {
ret = se->load_state(f, se->opaque, version_id);
if (ret < 0) {
fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
instance_id, idstr);
return ret;
}
}
/* always seek to exact end of record */
qemu_fseek(f, cur_pos + record_len, SEEK_SET);
}
if (qemu_file_has_error(f))
return -EIO;
return 0;
}
int qemu_loadvm_state(QEMUFile *f)
{
LoadStateEntry *first_le = NULL;
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)
return qemu_loadvm_state_v2(f);
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;
LoadStateEntry *le;
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;
le->next = first_le;
first_le = le;
le->se->load_state(f, le->se->opaque, le->version_id);
break;
case QEMU_VM_SECTION_PART:
case QEMU_VM_SECTION_END:
section_id = qemu_get_be32(f);
for (le = first_le; le && le->section_id != section_id; le = le->next);
if (le == NULL) {
fprintf(stderr, "Unknown savevm section %d\n", section_id);
ret = -EINVAL;
goto out;
}
le->se->load_state(f, le->se->opaque, le->version_id);
break;
default:
fprintf(stderr, "Unknown savevm section type %d\n", section_type);
ret = -EINVAL;
goto out;
}
}
ret = 0;
out:
while (first_le) {
LoadStateEntry *le = first_le;
first_le = first_le->next;
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;
int i;
if (bs_snapshots)
return bs_snapshots;
for(i = 0; i <= nb_drives; i++) {
bs = drives_table[i].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;
}
void do_savevm(Monitor *mon, const char *name)
{
BlockDriverState *bs, *bs1;
QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
int must_delete, ret, i;
BlockDriverInfo bdi1, *bdi = &bdi1;
QEMUFile *f;
int saved_vm_running;
uint32_t vm_state_size;
#ifdef _WIN32
struct _timeb tb;
#else
struct timeval tv;
#endif
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);
must_delete = 0;
if (name) {
ret = bdrv_snapshot_find(bs, old_sn, name);
if (ret >= 0) {
must_delete = 1;
}
}
memset(sn, 0, sizeof(*sn));
if (must_delete) {
pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
} else {
if (name)
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);
if (bdrv_get_info(bs, bdi) < 0 || bdi->vm_state_offset <= 0) {
monitor_printf(mon, "Device %s does not support VM state snapshots\n",
bdrv_get_device_name(bs));
goto the_end;
}
/* save the VM state */
f = qemu_fopen_bdrv(bs, bdi->vm_state_offset, 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 */
for(i = 0; i < nb_drives; i++) {
bs1 = drives_table[i].bdrv;
if (bdrv_has_snapshot(bs1)) {
if (must_delete) {
ret = bdrv_snapshot_delete(bs1, old_sn->id_str);
if (ret < 0) {
monitor_printf(mon,
"Error while deleting snapshot on '%s'\n",
bdrv_get_device_name(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 do_loadvm(Monitor *mon, const char *name)
{
BlockDriverState *bs, *bs1;
BlockDriverInfo bdi1, *bdi = &bdi1;
QEMUSnapshotInfo sn;
QEMUFile *f;
int i, ret;
int saved_vm_running;
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No block device supports snapshots\n");
return;
}
/* Flush all IO requests so they don't interfere with the new state. */
qemu_aio_flush();
saved_vm_running = vm_running;
vm_stop(0);
for(i = 0; i <= nb_drives; i++) {
bs1 = drives_table[i].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)
goto the_end;
}
}
}
if (bdrv_get_info(bs, bdi) < 0 || bdi->vm_state_offset <= 0) {
monitor_printf(mon, "Device %s does not support VM state snapshots\n",
bdrv_get_device_name(bs));
return;
}
/* Don't even try to load empty VM states */
ret = bdrv_snapshot_find(bs, &sn, name);
if ((ret >= 0) && (sn.vm_state_size == 0))
goto the_end;
/* restore the VM state */
f = qemu_fopen_bdrv(bs, bdi->vm_state_offset, 0);
if (!f) {
monitor_printf(mon, "Could not open VM state file\n");
goto the_end;
}
ret = qemu_loadvm_state(f);
qemu_fclose(f);
if (ret < 0) {
monitor_printf(mon, "Error %d while loading VM state\n", ret);
}
the_end:
if (saved_vm_running)
vm_start();
}
void do_delvm(Monitor *mon, const char *name)
{
BlockDriverState *bs, *bs1;
int i, ret;
bs = get_bs_snapshots();
if (!bs) {
monitor_printf(mon, "No block device supports snapshots\n");
return;
}
for(i = 0; i <= nb_drives; i++) {
bs1 = drives_table[i].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)
{
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:");
for(i = 0; i <= nb_drives; i++) {
bs1 = drives_table[i].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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