m25p80: Initial implementation of SPI flash device
[qemu-kvm.git] / savevm.c
blob31fd2e0ad37f9d34daa96c80d1f0c59eb703e40c
1 /*
2 * QEMU System Emulator
4 * Copyright (c) 2003-2008 Fabrice Bellard
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
24 #include <unistd.h>
25 #include <fcntl.h>
26 #include <time.h>
27 #include <errno.h>
28 #include <sys/time.h>
29 #include <zlib.h>
31 /* Needed early for CONFIG_BSD etc. */
32 #include "config-host.h"
34 #ifndef _WIN32
35 #include <sys/times.h>
36 #include <sys/wait.h>
37 #include <termios.h>
38 #include <sys/mman.h>
39 #include <sys/ioctl.h>
40 #include <sys/resource.h>
41 #include <sys/socket.h>
42 #include <netinet/in.h>
43 #include <net/if.h>
44 #include <arpa/inet.h>
45 #include <dirent.h>
46 #include <netdb.h>
47 #include <sys/select.h>
48 #ifdef CONFIG_BSD
49 #include <sys/stat.h>
50 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
51 #include <libutil.h>
52 #else
53 #include <util.h>
54 #endif
55 #ifdef __linux__
56 #include <pty.h>
57 #include <malloc.h>
58 #include <linux/rtc.h>
59 #endif
60 #endif
61 #endif
63 #ifdef _WIN32
64 #include <windows.h>
65 #include <malloc.h>
66 #include <sys/timeb.h>
67 #include <mmsystem.h>
68 #define getopt_long_only getopt_long
69 #define memalign(align, size) malloc(size)
70 #endif
72 #include "qemu-common.h"
73 #include "hw/hw.h"
74 #include "hw/qdev.h"
75 #include "net.h"
76 #include "monitor.h"
77 #include "sysemu.h"
78 #include "qemu-timer.h"
79 #include "qemu-char.h"
80 #include "audio/audio.h"
81 #include "migration.h"
82 #include "qemu_socket.h"
83 #include "qemu-queue.h"
84 #include "qemu-timer.h"
85 #include "cpus.h"
86 #include "memory.h"
87 #include "qmp-commands.h"
88 #include "trace.h"
90 #define SELF_ANNOUNCE_ROUNDS 5
92 #ifndef ETH_P_RARP
93 #define ETH_P_RARP 0x8035
94 #endif
95 #define ARP_HTYPE_ETH 0x0001
96 #define ARP_PTYPE_IP 0x0800
97 #define ARP_OP_REQUEST_REV 0x3
99 static int announce_self_create(uint8_t *buf,
100 uint8_t *mac_addr)
102 /* Ethernet header. */
103 memset(buf, 0xff, 6); /* destination MAC addr */
104 memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
105 *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
107 /* RARP header. */
108 *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
109 *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
110 *(buf + 18) = 6; /* hardware addr length (ethernet) */
111 *(buf + 19) = 4; /* protocol addr length (IPv4) */
112 *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
113 memcpy(buf + 22, mac_addr, 6); /* source hw addr */
114 memset(buf + 28, 0x00, 4); /* source protocol addr */
115 memcpy(buf + 32, mac_addr, 6); /* target hw addr */
116 memset(buf + 38, 0x00, 4); /* target protocol addr */
118 /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
119 memset(buf + 42, 0x00, 18);
121 return 60; /* len (FCS will be added by hardware) */
124 static void qemu_announce_self_iter(NICState *nic, void *opaque)
126 uint8_t buf[60];
127 int len;
129 len = announce_self_create(buf, nic->conf->macaddr.a);
131 qemu_send_packet_raw(&nic->nc, buf, len);
135 static void qemu_announce_self_once(void *opaque)
137 static int count = SELF_ANNOUNCE_ROUNDS;
138 QEMUTimer *timer = *(QEMUTimer **)opaque;
140 qemu_foreach_nic(qemu_announce_self_iter, NULL);
142 if (--count) {
143 /* delay 50ms, 150ms, 250ms, ... */
144 qemu_mod_timer(timer, qemu_get_clock_ms(rt_clock) +
145 50 + (SELF_ANNOUNCE_ROUNDS - count - 1) * 100);
146 } else {
147 qemu_del_timer(timer);
148 qemu_free_timer(timer);
152 void qemu_announce_self(void)
154 static QEMUTimer *timer;
155 timer = qemu_new_timer_ms(rt_clock, qemu_announce_self_once, &timer);
156 qemu_announce_self_once(&timer);
159 /***********************************************************/
160 /* savevm/loadvm support */
162 #define IO_BUF_SIZE 32768
164 struct QEMUFile {
165 QEMUFilePutBufferFunc *put_buffer;
166 QEMUFileGetBufferFunc *get_buffer;
167 QEMUFileCloseFunc *close;
168 QEMUFileRateLimit *rate_limit;
169 QEMUFileSetRateLimit *set_rate_limit;
170 QEMUFileGetRateLimit *get_rate_limit;
171 void *opaque;
172 int is_write;
174 int64_t buf_offset; /* start of buffer when writing, end of buffer
175 when reading */
176 int buf_index;
177 int buf_size; /* 0 when writing */
178 uint8_t buf[IO_BUF_SIZE];
180 int last_error;
183 typedef struct QEMUFileStdio
185 FILE *stdio_file;
186 QEMUFile *file;
187 } QEMUFileStdio;
189 typedef struct QEMUFileSocket
191 int fd;
192 QEMUFile *file;
193 } QEMUFileSocket;
195 static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
197 QEMUFileSocket *s = opaque;
198 ssize_t len;
200 do {
201 len = qemu_recv(s->fd, buf, size, 0);
202 } while (len == -1 && socket_error() == EINTR);
204 if (len == -1)
205 len = -socket_error();
207 return len;
210 static int socket_close(void *opaque)
212 QEMUFileSocket *s = opaque;
213 g_free(s);
214 return 0;
217 static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
219 QEMUFileStdio *s = opaque;
220 return fwrite(buf, 1, size, s->stdio_file);
223 static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
225 QEMUFileStdio *s = opaque;
226 FILE *fp = s->stdio_file;
227 int bytes;
229 do {
230 clearerr(fp);
231 bytes = fread(buf, 1, size, fp);
232 } while ((bytes == 0) && ferror(fp) && (errno == EINTR));
233 return bytes;
236 static int stdio_pclose(void *opaque)
238 QEMUFileStdio *s = opaque;
239 int ret;
240 ret = pclose(s->stdio_file);
241 if (ret == -1) {
242 ret = -errno;
244 g_free(s);
245 return ret;
248 static int stdio_fclose(void *opaque)
250 QEMUFileStdio *s = opaque;
251 int ret = 0;
252 if (fclose(s->stdio_file) == EOF) {
253 ret = -errno;
255 g_free(s);
256 return ret;
259 QEMUFile *qemu_popen(FILE *stdio_file, const char *mode)
261 QEMUFileStdio *s;
263 if (stdio_file == NULL || mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
264 fprintf(stderr, "qemu_popen: Argument validity check failed\n");
265 return NULL;
268 s = g_malloc0(sizeof(QEMUFileStdio));
270 s->stdio_file = stdio_file;
272 if(mode[0] == 'r') {
273 s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_pclose,
274 NULL, NULL, NULL);
275 } else {
276 s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_pclose,
277 NULL, NULL, NULL);
279 return s->file;
282 QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
284 FILE *popen_file;
286 popen_file = popen(command, mode);
287 if(popen_file == NULL) {
288 return NULL;
291 return qemu_popen(popen_file, mode);
294 int qemu_stdio_fd(QEMUFile *f)
296 QEMUFileStdio *p;
297 int fd;
299 p = (QEMUFileStdio *)f->opaque;
300 fd = fileno(p->stdio_file);
302 return fd;
305 QEMUFile *qemu_fdopen(int fd, const char *mode)
307 QEMUFileStdio *s;
309 if (mode == NULL ||
310 (mode[0] != 'r' && mode[0] != 'w') ||
311 mode[1] != 'b' || mode[2] != 0) {
312 fprintf(stderr, "qemu_fdopen: Argument validity check failed\n");
313 return NULL;
316 s = g_malloc0(sizeof(QEMUFileStdio));
317 s->stdio_file = fdopen(fd, mode);
318 if (!s->stdio_file)
319 goto fail;
321 if(mode[0] == 'r') {
322 s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose,
323 NULL, NULL, NULL);
324 } else {
325 s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose,
326 NULL, NULL, NULL);
328 return s->file;
330 fail:
331 g_free(s);
332 return NULL;
335 QEMUFile *qemu_fopen_socket(int fd)
337 QEMUFileSocket *s = g_malloc0(sizeof(QEMUFileSocket));
339 s->fd = fd;
340 s->file = qemu_fopen_ops(s, NULL, socket_get_buffer, socket_close,
341 NULL, NULL, NULL);
342 return s->file;
345 static int file_put_buffer(void *opaque, const uint8_t *buf,
346 int64_t pos, int size)
348 QEMUFileStdio *s = opaque;
349 fseek(s->stdio_file, pos, SEEK_SET);
350 return fwrite(buf, 1, size, s->stdio_file);
353 static int file_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
355 QEMUFileStdio *s = opaque;
356 fseek(s->stdio_file, pos, SEEK_SET);
357 return fread(buf, 1, size, s->stdio_file);
360 QEMUFile *qemu_fopen(const char *filename, const char *mode)
362 QEMUFileStdio *s;
364 if (mode == NULL ||
365 (mode[0] != 'r' && mode[0] != 'w') ||
366 mode[1] != 'b' || mode[2] != 0) {
367 fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
368 return NULL;
371 s = g_malloc0(sizeof(QEMUFileStdio));
373 s->stdio_file = fopen(filename, mode);
374 if (!s->stdio_file)
375 goto fail;
377 if(mode[0] == 'w') {
378 s->file = qemu_fopen_ops(s, file_put_buffer, NULL, stdio_fclose,
379 NULL, NULL, NULL);
380 } else {
381 s->file = qemu_fopen_ops(s, NULL, file_get_buffer, stdio_fclose,
382 NULL, NULL, NULL);
384 return s->file;
385 fail:
386 g_free(s);
387 return NULL;
390 static int block_put_buffer(void *opaque, const uint8_t *buf,
391 int64_t pos, int size)
393 bdrv_save_vmstate(opaque, buf, pos, size);
394 return size;
397 static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
399 return bdrv_load_vmstate(opaque, buf, pos, size);
402 static int bdrv_fclose(void *opaque)
404 return bdrv_flush(opaque);
407 static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable)
409 if (is_writable)
410 return qemu_fopen_ops(bs, block_put_buffer, NULL, bdrv_fclose,
411 NULL, NULL, NULL);
412 return qemu_fopen_ops(bs, NULL, block_get_buffer, bdrv_fclose, NULL, NULL, NULL);
415 QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer,
416 QEMUFileGetBufferFunc *get_buffer,
417 QEMUFileCloseFunc *close,
418 QEMUFileRateLimit *rate_limit,
419 QEMUFileSetRateLimit *set_rate_limit,
420 QEMUFileGetRateLimit *get_rate_limit)
422 QEMUFile *f;
424 f = g_malloc0(sizeof(QEMUFile));
426 f->opaque = opaque;
427 f->put_buffer = put_buffer;
428 f->get_buffer = get_buffer;
429 f->close = close;
430 f->rate_limit = rate_limit;
431 f->set_rate_limit = set_rate_limit;
432 f->get_rate_limit = get_rate_limit;
433 f->is_write = 0;
435 return f;
438 int qemu_file_get_error(QEMUFile *f)
440 return f->last_error;
443 void qemu_file_set_error(QEMUFile *f, int ret)
445 f->last_error = ret;
448 /** Sets last_error conditionally
450 * Sets last_error only if ret is negative _and_ no error
451 * was set before.
453 static void qemu_file_set_if_error(QEMUFile *f, int ret)
455 if (ret < 0 && !f->last_error) {
456 qemu_file_set_error(f, ret);
460 /** Flushes QEMUFile buffer
462 * In case of error, last_error is set.
464 void qemu_fflush(QEMUFile *f)
466 if (!f->put_buffer)
467 return;
469 if (f->is_write && f->buf_index > 0) {
470 int len;
472 len = f->put_buffer(f->opaque, f->buf, f->buf_offset, f->buf_index);
473 if (len > 0)
474 f->buf_offset += f->buf_index;
475 else
476 qemu_file_set_error(f, -EINVAL);
477 f->buf_index = 0;
481 static void qemu_fill_buffer(QEMUFile *f)
483 int len;
484 int pending;
486 if (!f->get_buffer)
487 return;
489 if (f->is_write)
490 abort();
492 pending = f->buf_size - f->buf_index;
493 if (pending > 0) {
494 memmove(f->buf, f->buf + f->buf_index, pending);
496 f->buf_index = 0;
497 f->buf_size = pending;
499 len = f->get_buffer(f->opaque, f->buf + pending, f->buf_offset,
500 IO_BUF_SIZE - pending);
501 if (len > 0) {
502 f->buf_size += len;
503 f->buf_offset += len;
504 } else if (len == 0) {
505 f->last_error = -EIO;
506 } else if (len != -EAGAIN)
507 qemu_file_set_error(f, len);
510 /** Calls close function and set last_error if needed
512 * Internal function. qemu_fflush() must be called before this.
514 * Returns f->close() return value, or 0 if close function is not set.
516 static int qemu_fclose_internal(QEMUFile *f)
518 int ret = 0;
519 if (f->close) {
520 ret = f->close(f->opaque);
521 qemu_file_set_if_error(f, ret);
523 return ret;
526 /** Closes the file
528 * Returns negative error value if any error happened on previous operations or
529 * while closing the file. Returns 0 or positive number on success.
531 * The meaning of return value on success depends on the specific backend
532 * being used.
534 int qemu_fclose(QEMUFile *f)
536 int ret;
537 qemu_fflush(f);
538 ret = qemu_fclose_internal(f);
539 /* If any error was spotted before closing, we should report it
540 * instead of the close() return value.
542 if (f->last_error) {
543 ret = f->last_error;
545 g_free(f);
546 return ret;
549 void qemu_file_put_notify(QEMUFile *f)
551 f->put_buffer(f->opaque, NULL, 0, 0);
554 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
556 int l;
558 if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
559 fprintf(stderr,
560 "Attempted to write to buffer while read buffer is not empty\n");
561 abort();
564 while (!f->last_error && size > 0) {
565 l = IO_BUF_SIZE - f->buf_index;
566 if (l > size)
567 l = size;
568 memcpy(f->buf + f->buf_index, buf, l);
569 f->is_write = 1;
570 f->buf_index += l;
571 buf += l;
572 size -= l;
573 if (f->buf_index >= IO_BUF_SIZE)
574 qemu_fflush(f);
578 void qemu_put_byte(QEMUFile *f, int v)
580 if (!f->last_error && f->is_write == 0 && f->buf_index > 0) {
581 fprintf(stderr,
582 "Attempted to write to buffer while read buffer is not empty\n");
583 abort();
586 f->buf[f->buf_index++] = v;
587 f->is_write = 1;
588 if (f->buf_index >= IO_BUF_SIZE)
589 qemu_fflush(f);
592 static void qemu_file_skip(QEMUFile *f, int size)
594 if (f->buf_index + size <= f->buf_size) {
595 f->buf_index += size;
599 static int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset)
601 int pending;
602 int index;
604 if (f->is_write) {
605 abort();
608 index = f->buf_index + offset;
609 pending = f->buf_size - index;
610 if (pending < size) {
611 qemu_fill_buffer(f);
612 index = f->buf_index + offset;
613 pending = f->buf_size - index;
616 if (pending <= 0) {
617 return 0;
619 if (size > pending) {
620 size = pending;
623 memcpy(buf, f->buf + index, size);
624 return size;
627 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size)
629 int pending = size;
630 int done = 0;
632 while (pending > 0) {
633 int res;
635 res = qemu_peek_buffer(f, buf, pending, 0);
636 if (res == 0) {
637 return done;
639 qemu_file_skip(f, res);
640 buf += res;
641 pending -= res;
642 done += res;
644 return done;
647 static int qemu_peek_byte(QEMUFile *f, int offset)
649 int index = f->buf_index + offset;
651 if (f->is_write) {
652 abort();
655 if (index >= f->buf_size) {
656 qemu_fill_buffer(f);
657 index = f->buf_index + offset;
658 if (index >= f->buf_size) {
659 return 0;
662 return f->buf[index];
665 int qemu_get_byte(QEMUFile *f)
667 int result;
669 result = qemu_peek_byte(f, 0);
670 qemu_file_skip(f, 1);
671 return result;
674 int64_t qemu_ftell(QEMUFile *f)
676 return f->buf_offset - f->buf_size + f->buf_index;
679 int64_t qemu_fseek(QEMUFile *f, int64_t pos, int whence)
681 if (whence == SEEK_SET) {
682 /* nothing to do */
683 } else if (whence == SEEK_CUR) {
684 pos += qemu_ftell(f);
685 } else {
686 /* SEEK_END not supported */
687 return -1;
689 if (f->put_buffer) {
690 qemu_fflush(f);
691 f->buf_offset = pos;
692 } else {
693 f->buf_offset = pos;
694 f->buf_index = 0;
695 f->buf_size = 0;
697 return pos;
700 int qemu_file_rate_limit(QEMUFile *f)
702 if (f->rate_limit)
703 return f->rate_limit(f->opaque);
705 return 0;
708 int64_t qemu_file_get_rate_limit(QEMUFile *f)
710 if (f->get_rate_limit)
711 return f->get_rate_limit(f->opaque);
713 return 0;
716 int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate)
718 /* any failed or completed migration keeps its state to allow probing of
719 * migration data, but has no associated file anymore */
720 if (f && f->set_rate_limit)
721 return f->set_rate_limit(f->opaque, new_rate);
723 return 0;
726 void qemu_put_be16(QEMUFile *f, unsigned int v)
728 qemu_put_byte(f, v >> 8);
729 qemu_put_byte(f, v);
732 void qemu_put_be32(QEMUFile *f, unsigned int v)
734 qemu_put_byte(f, v >> 24);
735 qemu_put_byte(f, v >> 16);
736 qemu_put_byte(f, v >> 8);
737 qemu_put_byte(f, v);
740 void qemu_put_be64(QEMUFile *f, uint64_t v)
742 qemu_put_be32(f, v >> 32);
743 qemu_put_be32(f, v);
746 unsigned int qemu_get_be16(QEMUFile *f)
748 unsigned int v;
749 v = qemu_get_byte(f) << 8;
750 v |= qemu_get_byte(f);
751 return v;
754 unsigned int qemu_get_be32(QEMUFile *f)
756 unsigned int v;
757 v = qemu_get_byte(f) << 24;
758 v |= qemu_get_byte(f) << 16;
759 v |= qemu_get_byte(f) << 8;
760 v |= qemu_get_byte(f);
761 return v;
764 uint64_t qemu_get_be64(QEMUFile *f)
766 uint64_t v;
767 v = (uint64_t)qemu_get_be32(f) << 32;
768 v |= qemu_get_be32(f);
769 return v;
773 /* timer */
775 void qemu_put_timer(QEMUFile *f, QEMUTimer *ts)
777 uint64_t expire_time;
779 expire_time = qemu_timer_expire_time_ns(ts);
780 qemu_put_be64(f, expire_time);
783 void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
785 uint64_t expire_time;
787 expire_time = qemu_get_be64(f);
788 if (expire_time != -1) {
789 qemu_mod_timer_ns(ts, expire_time);
790 } else {
791 qemu_del_timer(ts);
796 /* bool */
798 static int get_bool(QEMUFile *f, void *pv, size_t size)
800 bool *v = pv;
801 *v = qemu_get_byte(f);
802 return 0;
805 static void put_bool(QEMUFile *f, void *pv, size_t size)
807 bool *v = pv;
808 qemu_put_byte(f, *v);
811 const VMStateInfo vmstate_info_bool = {
812 .name = "bool",
813 .get = get_bool,
814 .put = put_bool,
817 /* 8 bit int */
819 static int get_int8(QEMUFile *f, void *pv, size_t size)
821 int8_t *v = pv;
822 qemu_get_s8s(f, v);
823 return 0;
826 static void put_int8(QEMUFile *f, void *pv, size_t size)
828 int8_t *v = pv;
829 qemu_put_s8s(f, v);
832 const VMStateInfo vmstate_info_int8 = {
833 .name = "int8",
834 .get = get_int8,
835 .put = put_int8,
838 /* 16 bit int */
840 static int get_int16(QEMUFile *f, void *pv, size_t size)
842 int16_t *v = pv;
843 qemu_get_sbe16s(f, v);
844 return 0;
847 static void put_int16(QEMUFile *f, void *pv, size_t size)
849 int16_t *v = pv;
850 qemu_put_sbe16s(f, v);
853 const VMStateInfo vmstate_info_int16 = {
854 .name = "int16",
855 .get = get_int16,
856 .put = put_int16,
859 /* 32 bit int */
861 static int get_int32(QEMUFile *f, void *pv, size_t size)
863 int32_t *v = pv;
864 qemu_get_sbe32s(f, v);
865 return 0;
868 static void put_int32(QEMUFile *f, void *pv, size_t size)
870 int32_t *v = pv;
871 qemu_put_sbe32s(f, v);
874 const VMStateInfo vmstate_info_int32 = {
875 .name = "int32",
876 .get = get_int32,
877 .put = put_int32,
880 /* 32 bit int. See that the received value is the same than the one
881 in the field */
883 static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
885 int32_t *v = pv;
886 int32_t v2;
887 qemu_get_sbe32s(f, &v2);
889 if (*v == v2)
890 return 0;
891 return -EINVAL;
894 const VMStateInfo vmstate_info_int32_equal = {
895 .name = "int32 equal",
896 .get = get_int32_equal,
897 .put = put_int32,
900 /* 32 bit int. See that the received value is the less or the same
901 than the one in the field */
903 static int get_int32_le(QEMUFile *f, void *pv, size_t size)
905 int32_t *old = pv;
906 int32_t new;
907 qemu_get_sbe32s(f, &new);
909 if (*old <= new)
910 return 0;
911 return -EINVAL;
914 const VMStateInfo vmstate_info_int32_le = {
915 .name = "int32 equal",
916 .get = get_int32_le,
917 .put = put_int32,
920 /* 64 bit int */
922 static int get_int64(QEMUFile *f, void *pv, size_t size)
924 int64_t *v = pv;
925 qemu_get_sbe64s(f, v);
926 return 0;
929 static void put_int64(QEMUFile *f, void *pv, size_t size)
931 int64_t *v = pv;
932 qemu_put_sbe64s(f, v);
935 const VMStateInfo vmstate_info_int64 = {
936 .name = "int64",
937 .get = get_int64,
938 .put = put_int64,
941 /* 8 bit unsigned int */
943 static int get_uint8(QEMUFile *f, void *pv, size_t size)
945 uint8_t *v = pv;
946 qemu_get_8s(f, v);
947 return 0;
950 static void put_uint8(QEMUFile *f, void *pv, size_t size)
952 uint8_t *v = pv;
953 qemu_put_8s(f, v);
956 const VMStateInfo vmstate_info_uint8 = {
957 .name = "uint8",
958 .get = get_uint8,
959 .put = put_uint8,
962 /* 16 bit unsigned int */
964 static int get_uint16(QEMUFile *f, void *pv, size_t size)
966 uint16_t *v = pv;
967 qemu_get_be16s(f, v);
968 return 0;
971 static void put_uint16(QEMUFile *f, void *pv, size_t size)
973 uint16_t *v = pv;
974 qemu_put_be16s(f, v);
977 const VMStateInfo vmstate_info_uint16 = {
978 .name = "uint16",
979 .get = get_uint16,
980 .put = put_uint16,
983 /* 32 bit unsigned int */
985 static int get_uint32(QEMUFile *f, void *pv, size_t size)
987 uint32_t *v = pv;
988 qemu_get_be32s(f, v);
989 return 0;
992 static void put_uint32(QEMUFile *f, void *pv, size_t size)
994 uint32_t *v = pv;
995 qemu_put_be32s(f, v);
998 const VMStateInfo vmstate_info_uint32 = {
999 .name = "uint32",
1000 .get = get_uint32,
1001 .put = put_uint32,
1004 /* 32 bit uint. See that the received value is the same than the one
1005 in the field */
1007 static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
1009 uint32_t *v = pv;
1010 uint32_t v2;
1011 qemu_get_be32s(f, &v2);
1013 if (*v == v2) {
1014 return 0;
1016 return -EINVAL;
1019 const VMStateInfo vmstate_info_uint32_equal = {
1020 .name = "uint32 equal",
1021 .get = get_uint32_equal,
1022 .put = put_uint32,
1025 /* 64 bit unsigned int */
1027 static int get_uint64(QEMUFile *f, void *pv, size_t size)
1029 uint64_t *v = pv;
1030 qemu_get_be64s(f, v);
1031 return 0;
1034 static void put_uint64(QEMUFile *f, void *pv, size_t size)
1036 uint64_t *v = pv;
1037 qemu_put_be64s(f, v);
1040 const VMStateInfo vmstate_info_uint64 = {
1041 .name = "uint64",
1042 .get = get_uint64,
1043 .put = put_uint64,
1046 /* 8 bit int. See that the received value is the same than the one
1047 in the field */
1049 static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
1051 uint8_t *v = pv;
1052 uint8_t v2;
1053 qemu_get_8s(f, &v2);
1055 if (*v == v2)
1056 return 0;
1057 return -EINVAL;
1060 const VMStateInfo vmstate_info_uint8_equal = {
1061 .name = "uint8 equal",
1062 .get = get_uint8_equal,
1063 .put = put_uint8,
1066 /* 16 bit unsigned int int. See that the received value is the same than the one
1067 in the field */
1069 static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
1071 uint16_t *v = pv;
1072 uint16_t v2;
1073 qemu_get_be16s(f, &v2);
1075 if (*v == v2)
1076 return 0;
1077 return -EINVAL;
1080 const VMStateInfo vmstate_info_uint16_equal = {
1081 .name = "uint16 equal",
1082 .get = get_uint16_equal,
1083 .put = put_uint16,
1086 /* timers */
1088 static int get_timer(QEMUFile *f, void *pv, size_t size)
1090 QEMUTimer *v = pv;
1091 qemu_get_timer(f, v);
1092 return 0;
1095 static void put_timer(QEMUFile *f, void *pv, size_t size)
1097 QEMUTimer *v = pv;
1098 qemu_put_timer(f, v);
1101 const VMStateInfo vmstate_info_timer = {
1102 .name = "timer",
1103 .get = get_timer,
1104 .put = put_timer,
1107 /* uint8_t buffers */
1109 static int get_buffer(QEMUFile *f, void *pv, size_t size)
1111 uint8_t *v = pv;
1112 qemu_get_buffer(f, v, size);
1113 return 0;
1116 static void put_buffer(QEMUFile *f, void *pv, size_t size)
1118 uint8_t *v = pv;
1119 qemu_put_buffer(f, v, size);
1122 const VMStateInfo vmstate_info_buffer = {
1123 .name = "buffer",
1124 .get = get_buffer,
1125 .put = put_buffer,
1128 /* unused buffers: space that was used for some fields that are
1129 not useful anymore */
1131 static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
1133 uint8_t buf[1024];
1134 int block_len;
1136 while (size > 0) {
1137 block_len = MIN(sizeof(buf), size);
1138 size -= block_len;
1139 qemu_get_buffer(f, buf, block_len);
1141 return 0;
1144 static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
1146 static const uint8_t buf[1024];
1147 int block_len;
1149 while (size > 0) {
1150 block_len = MIN(sizeof(buf), size);
1151 size -= block_len;
1152 qemu_put_buffer(f, buf, block_len);
1156 const VMStateInfo vmstate_info_unused_buffer = {
1157 .name = "unused_buffer",
1158 .get = get_unused_buffer,
1159 .put = put_unused_buffer,
1162 typedef struct CompatEntry {
1163 char idstr[256];
1164 int instance_id;
1165 } CompatEntry;
1167 typedef struct SaveStateEntry {
1168 QTAILQ_ENTRY(SaveStateEntry) entry;
1169 char idstr[256];
1170 int instance_id;
1171 int alias_id;
1172 int version_id;
1173 int section_id;
1174 SaveVMHandlers *ops;
1175 const VMStateDescription *vmsd;
1176 void *opaque;
1177 CompatEntry *compat;
1178 int no_migrate;
1179 int is_ram;
1180 } SaveStateEntry;
1183 static QTAILQ_HEAD(savevm_handlers, SaveStateEntry) savevm_handlers =
1184 QTAILQ_HEAD_INITIALIZER(savevm_handlers);
1185 static int global_section_id;
1187 static int calculate_new_instance_id(const char *idstr)
1189 SaveStateEntry *se;
1190 int instance_id = 0;
1192 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1193 if (strcmp(idstr, se->idstr) == 0
1194 && instance_id <= se->instance_id) {
1195 instance_id = se->instance_id + 1;
1198 return instance_id;
1201 static int calculate_compat_instance_id(const char *idstr)
1203 SaveStateEntry *se;
1204 int instance_id = 0;
1206 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1207 if (!se->compat)
1208 continue;
1210 if (strcmp(idstr, se->compat->idstr) == 0
1211 && instance_id <= se->compat->instance_id) {
1212 instance_id = se->compat->instance_id + 1;
1215 return instance_id;
1218 /* TODO: Individual devices generally have very little idea about the rest
1219 of the system, so instance_id should be removed/replaced.
1220 Meanwhile pass -1 as instance_id if you do not already have a clearly
1221 distinguishing id for all instances of your device class. */
1222 int register_savevm_live(DeviceState *dev,
1223 const char *idstr,
1224 int instance_id,
1225 int version_id,
1226 SaveVMHandlers *ops,
1227 void *opaque)
1229 SaveStateEntry *se;
1231 se = g_malloc0(sizeof(SaveStateEntry));
1232 se->version_id = version_id;
1233 se->section_id = global_section_id++;
1234 se->ops = ops;
1235 se->opaque = opaque;
1236 se->vmsd = NULL;
1237 se->no_migrate = 0;
1238 /* if this is a live_savem then set is_ram */
1239 if (ops->save_live_setup != NULL) {
1240 se->is_ram = 1;
1243 if (dev) {
1244 char *id = qdev_get_dev_path(dev);
1245 if (id) {
1246 pstrcpy(se->idstr, sizeof(se->idstr), id);
1247 pstrcat(se->idstr, sizeof(se->idstr), "/");
1248 g_free(id);
1250 se->compat = g_malloc0(sizeof(CompatEntry));
1251 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr);
1252 se->compat->instance_id = instance_id == -1 ?
1253 calculate_compat_instance_id(idstr) : instance_id;
1254 instance_id = -1;
1257 pstrcat(se->idstr, sizeof(se->idstr), idstr);
1259 if (instance_id == -1) {
1260 se->instance_id = calculate_new_instance_id(se->idstr);
1261 } else {
1262 se->instance_id = instance_id;
1264 assert(!se->compat || se->instance_id == 0);
1265 /* add at the end of list */
1266 QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1267 return 0;
1270 int register_savevm(DeviceState *dev,
1271 const char *idstr,
1272 int instance_id,
1273 int version_id,
1274 SaveStateHandler *save_state,
1275 LoadStateHandler *load_state,
1276 void *opaque)
1278 SaveVMHandlers *ops = g_malloc0(sizeof(SaveVMHandlers));
1279 ops->save_state = save_state;
1280 ops->load_state = load_state;
1281 return register_savevm_live(dev, idstr, instance_id, version_id,
1282 ops, opaque);
1285 void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque)
1287 SaveStateEntry *se, *new_se;
1288 char id[256] = "";
1290 if (dev) {
1291 char *path = qdev_get_dev_path(dev);
1292 if (path) {
1293 pstrcpy(id, sizeof(id), path);
1294 pstrcat(id, sizeof(id), "/");
1295 g_free(path);
1298 pstrcat(id, sizeof(id), idstr);
1300 QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1301 if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) {
1302 QTAILQ_REMOVE(&savevm_handlers, se, entry);
1303 if (se->compat) {
1304 g_free(se->compat);
1306 g_free(se->ops);
1307 g_free(se);
1312 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
1313 const VMStateDescription *vmsd,
1314 void *opaque, int alias_id,
1315 int required_for_version)
1317 SaveStateEntry *se;
1319 /* If this triggers, alias support can be dropped for the vmsd. */
1320 assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id);
1322 se = g_malloc0(sizeof(SaveStateEntry));
1323 se->version_id = vmsd->version_id;
1324 se->section_id = global_section_id++;
1325 se->opaque = opaque;
1326 se->vmsd = vmsd;
1327 se->alias_id = alias_id;
1328 se->no_migrate = vmsd->unmigratable;
1330 if (dev) {
1331 char *id = qdev_get_dev_path(dev);
1332 if (id) {
1333 pstrcpy(se->idstr, sizeof(se->idstr), id);
1334 pstrcat(se->idstr, sizeof(se->idstr), "/");
1335 g_free(id);
1337 se->compat = g_malloc0(sizeof(CompatEntry));
1338 pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
1339 se->compat->instance_id = instance_id == -1 ?
1340 calculate_compat_instance_id(vmsd->name) : instance_id;
1341 instance_id = -1;
1344 pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
1346 if (instance_id == -1) {
1347 se->instance_id = calculate_new_instance_id(se->idstr);
1348 } else {
1349 se->instance_id = instance_id;
1351 assert(!se->compat || se->instance_id == 0);
1352 /* add at the end of list */
1353 QTAILQ_INSERT_TAIL(&savevm_handlers, se, entry);
1354 return 0;
1357 int vmstate_register(DeviceState *dev, int instance_id,
1358 const VMStateDescription *vmsd, void *opaque)
1360 return vmstate_register_with_alias_id(dev, instance_id, vmsd,
1361 opaque, -1, 0);
1364 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
1365 void *opaque)
1367 SaveStateEntry *se, *new_se;
1369 QTAILQ_FOREACH_SAFE(se, &savevm_handlers, entry, new_se) {
1370 if (se->vmsd == vmsd && se->opaque == opaque) {
1371 QTAILQ_REMOVE(&savevm_handlers, se, entry);
1372 if (se->compat) {
1373 g_free(se->compat);
1375 g_free(se);
1380 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1381 void *opaque);
1382 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1383 void *opaque);
1385 int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
1386 void *opaque, int version_id)
1388 VMStateField *field = vmsd->fields;
1389 int ret;
1391 if (version_id > vmsd->version_id) {
1392 return -EINVAL;
1394 if (version_id < vmsd->minimum_version_id_old) {
1395 return -EINVAL;
1397 if (version_id < vmsd->minimum_version_id) {
1398 return vmsd->load_state_old(f, opaque, version_id);
1400 if (vmsd->pre_load) {
1401 int ret = vmsd->pre_load(opaque);
1402 if (ret)
1403 return ret;
1405 while(field->name) {
1406 if ((field->field_exists &&
1407 field->field_exists(opaque, version_id)) ||
1408 (!field->field_exists &&
1409 field->version_id <= version_id)) {
1410 void *base_addr = opaque + field->offset;
1411 int i, n_elems = 1;
1412 int size = field->size;
1414 if (field->flags & VMS_VBUFFER) {
1415 size = *(int32_t *)(opaque+field->size_offset);
1416 if (field->flags & VMS_MULTIPLY) {
1417 size *= field->size;
1420 if (field->flags & VMS_ARRAY) {
1421 n_elems = field->num;
1422 } else if (field->flags & VMS_VARRAY_INT32) {
1423 n_elems = *(int32_t *)(opaque+field->num_offset);
1424 } else if (field->flags & VMS_VARRAY_UINT32) {
1425 n_elems = *(uint32_t *)(opaque+field->num_offset);
1426 } else if (field->flags & VMS_VARRAY_UINT16) {
1427 n_elems = *(uint16_t *)(opaque+field->num_offset);
1428 } else if (field->flags & VMS_VARRAY_UINT8) {
1429 n_elems = *(uint8_t *)(opaque+field->num_offset);
1431 if (field->flags & VMS_POINTER) {
1432 base_addr = *(void **)base_addr + field->start;
1434 for (i = 0; i < n_elems; i++) {
1435 void *addr = base_addr + size * i;
1437 if (field->flags & VMS_ARRAY_OF_POINTER) {
1438 addr = *(void **)addr;
1440 if (field->flags & VMS_STRUCT) {
1441 ret = vmstate_load_state(f, field->vmsd, addr, field->vmsd->version_id);
1442 } else {
1443 ret = field->info->get(f, addr, size);
1446 if (ret < 0) {
1447 return ret;
1451 field++;
1453 ret = vmstate_subsection_load(f, vmsd, opaque);
1454 if (ret != 0) {
1455 return ret;
1457 if (vmsd->post_load) {
1458 return vmsd->post_load(opaque, version_id);
1460 return 0;
1463 void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
1464 void *opaque)
1466 VMStateField *field = vmsd->fields;
1468 if (vmsd->pre_save) {
1469 vmsd->pre_save(opaque);
1471 while(field->name) {
1472 if (!field->field_exists ||
1473 field->field_exists(opaque, vmsd->version_id)) {
1474 void *base_addr = opaque + field->offset;
1475 int i, n_elems = 1;
1476 int size = field->size;
1478 if (field->flags & VMS_VBUFFER) {
1479 size = *(int32_t *)(opaque+field->size_offset);
1480 if (field->flags & VMS_MULTIPLY) {
1481 size *= field->size;
1484 if (field->flags & VMS_ARRAY) {
1485 n_elems = field->num;
1486 } else if (field->flags & VMS_VARRAY_INT32) {
1487 n_elems = *(int32_t *)(opaque+field->num_offset);
1488 } else if (field->flags & VMS_VARRAY_UINT32) {
1489 n_elems = *(uint32_t *)(opaque+field->num_offset);
1490 } else if (field->flags & VMS_VARRAY_UINT16) {
1491 n_elems = *(uint16_t *)(opaque+field->num_offset);
1492 } else if (field->flags & VMS_VARRAY_UINT8) {
1493 n_elems = *(uint8_t *)(opaque+field->num_offset);
1495 if (field->flags & VMS_POINTER) {
1496 base_addr = *(void **)base_addr + field->start;
1498 for (i = 0; i < n_elems; i++) {
1499 void *addr = base_addr + size * i;
1501 if (field->flags & VMS_ARRAY_OF_POINTER) {
1502 addr = *(void **)addr;
1504 if (field->flags & VMS_STRUCT) {
1505 vmstate_save_state(f, field->vmsd, addr);
1506 } else {
1507 field->info->put(f, addr, size);
1511 field++;
1513 vmstate_subsection_save(f, vmsd, opaque);
1516 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
1518 if (!se->vmsd) { /* Old style */
1519 return se->ops->load_state(f, se->opaque, version_id);
1521 return vmstate_load_state(f, se->vmsd, se->opaque, version_id);
1524 static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
1526 if (!se->vmsd) { /* Old style */
1527 se->ops->save_state(f, se->opaque);
1528 return;
1530 vmstate_save_state(f,se->vmsd, se->opaque);
1533 #define QEMU_VM_FILE_MAGIC 0x5145564d
1534 #define QEMU_VM_FILE_VERSION_COMPAT 0x00000002
1535 #define QEMU_VM_FILE_VERSION 0x00000003
1537 #define QEMU_VM_EOF 0x00
1538 #define QEMU_VM_SECTION_START 0x01
1539 #define QEMU_VM_SECTION_PART 0x02
1540 #define QEMU_VM_SECTION_END 0x03
1541 #define QEMU_VM_SECTION_FULL 0x04
1542 #define QEMU_VM_SUBSECTION 0x05
1544 bool qemu_savevm_state_blocked(Error **errp)
1546 SaveStateEntry *se;
1548 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1549 if (se->no_migrate) {
1550 error_set(errp, QERR_MIGRATION_NOT_SUPPORTED, se->idstr);
1551 return true;
1554 return false;
1557 int qemu_savevm_state_begin(QEMUFile *f,
1558 const MigrationParams *params)
1560 SaveStateEntry *se;
1561 int ret;
1563 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1564 if (!se->ops || !se->ops->set_params) {
1565 continue;
1567 se->ops->set_params(params, se->opaque);
1570 qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1571 qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1573 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1574 int len;
1576 if (!se->ops || !se->ops->save_live_setup) {
1577 continue;
1579 if (se->ops && se->ops->is_active) {
1580 if (!se->ops->is_active(se->opaque)) {
1581 continue;
1584 /* Section type */
1585 qemu_put_byte(f, QEMU_VM_SECTION_START);
1586 qemu_put_be32(f, se->section_id);
1588 /* ID string */
1589 len = strlen(se->idstr);
1590 qemu_put_byte(f, len);
1591 qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1593 qemu_put_be32(f, se->instance_id);
1594 qemu_put_be32(f, se->version_id);
1596 ret = se->ops->save_live_setup(f, se->opaque);
1597 if (ret < 0) {
1598 qemu_savevm_state_cancel(f);
1599 return ret;
1602 ret = qemu_file_get_error(f);
1603 if (ret != 0) {
1604 qemu_savevm_state_cancel(f);
1607 return ret;
1612 * this function has three return values:
1613 * negative: there was one error, and we have -errno.
1614 * 0 : We haven't finished, caller have to go again
1615 * 1 : We have finished, we can go to complete phase
1617 int qemu_savevm_state_iterate(QEMUFile *f)
1619 SaveStateEntry *se;
1620 int ret = 1;
1622 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1623 if (!se->ops || !se->ops->save_live_iterate) {
1624 continue;
1626 if (se->ops && se->ops->is_active) {
1627 if (!se->ops->is_active(se->opaque)) {
1628 continue;
1631 if (qemu_file_rate_limit(f)) {
1632 return 0;
1634 trace_savevm_section_start();
1635 /* Section type */
1636 qemu_put_byte(f, QEMU_VM_SECTION_PART);
1637 qemu_put_be32(f, se->section_id);
1639 ret = se->ops->save_live_iterate(f, se->opaque);
1640 trace_savevm_section_end(se->section_id);
1642 if (ret <= 0) {
1643 /* Do not proceed to the next vmstate before this one reported
1644 completion of the current stage. This serializes the migration
1645 and reduces the probability that a faster changing state is
1646 synchronized over and over again. */
1647 break;
1650 if (ret != 0) {
1651 return ret;
1653 ret = qemu_file_get_error(f);
1654 if (ret != 0) {
1655 qemu_savevm_state_cancel(f);
1657 return ret;
1660 int qemu_savevm_state_complete(QEMUFile *f)
1662 SaveStateEntry *se;
1663 int ret;
1665 cpu_synchronize_all_states();
1667 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1668 if (!se->ops || !se->ops->save_live_complete) {
1669 continue;
1671 if (se->ops && se->ops->is_active) {
1672 if (!se->ops->is_active(se->opaque)) {
1673 continue;
1676 trace_savevm_section_start();
1677 /* Section type */
1678 qemu_put_byte(f, QEMU_VM_SECTION_END);
1679 qemu_put_be32(f, se->section_id);
1681 ret = se->ops->save_live_complete(f, se->opaque);
1682 trace_savevm_section_end(se->section_id);
1683 if (ret < 0) {
1684 return ret;
1688 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1689 int len;
1691 if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
1692 continue;
1694 trace_savevm_section_start();
1695 /* Section type */
1696 qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1697 qemu_put_be32(f, se->section_id);
1699 /* ID string */
1700 len = strlen(se->idstr);
1701 qemu_put_byte(f, len);
1702 qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1704 qemu_put_be32(f, se->instance_id);
1705 qemu_put_be32(f, se->version_id);
1707 vmstate_save(f, se);
1708 trace_savevm_section_end(se->section_id);
1711 qemu_put_byte(f, QEMU_VM_EOF);
1713 return qemu_file_get_error(f);
1716 void qemu_savevm_state_cancel(QEMUFile *f)
1718 SaveStateEntry *se;
1720 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1721 if (se->ops && se->ops->cancel) {
1722 se->ops->cancel(se->opaque);
1727 static int qemu_savevm_state(QEMUFile *f)
1729 int ret;
1730 MigrationParams params = {
1731 .blk = 0,
1732 .shared = 0
1735 if (qemu_savevm_state_blocked(NULL)) {
1736 ret = -EINVAL;
1737 goto out;
1740 ret = qemu_savevm_state_begin(f, &params);
1741 if (ret < 0)
1742 goto out;
1744 do {
1745 ret = qemu_savevm_state_iterate(f);
1746 if (ret < 0)
1747 goto out;
1748 } while (ret == 0);
1750 ret = qemu_savevm_state_complete(f);
1752 out:
1753 if (ret == 0) {
1754 ret = qemu_file_get_error(f);
1757 return ret;
1760 static int qemu_save_device_state(QEMUFile *f)
1762 SaveStateEntry *se;
1764 qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
1765 qemu_put_be32(f, QEMU_VM_FILE_VERSION);
1767 cpu_synchronize_all_states();
1769 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1770 int len;
1772 if (se->is_ram) {
1773 continue;
1775 if ((!se->ops || !se->ops->save_state) && !se->vmsd) {
1776 continue;
1779 /* Section type */
1780 qemu_put_byte(f, QEMU_VM_SECTION_FULL);
1781 qemu_put_be32(f, se->section_id);
1783 /* ID string */
1784 len = strlen(se->idstr);
1785 qemu_put_byte(f, len);
1786 qemu_put_buffer(f, (uint8_t *)se->idstr, len);
1788 qemu_put_be32(f, se->instance_id);
1789 qemu_put_be32(f, se->version_id);
1791 vmstate_save(f, se);
1794 qemu_put_byte(f, QEMU_VM_EOF);
1796 return qemu_file_get_error(f);
1799 static SaveStateEntry *find_se(const char *idstr, int instance_id)
1801 SaveStateEntry *se;
1803 QTAILQ_FOREACH(se, &savevm_handlers, entry) {
1804 if (!strcmp(se->idstr, idstr) &&
1805 (instance_id == se->instance_id ||
1806 instance_id == se->alias_id))
1807 return se;
1808 /* Migrating from an older version? */
1809 if (strstr(se->idstr, idstr) && se->compat) {
1810 if (!strcmp(se->compat->idstr, idstr) &&
1811 (instance_id == se->compat->instance_id ||
1812 instance_id == se->alias_id))
1813 return se;
1816 return NULL;
1819 static const VMStateDescription *vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
1821 while(sub && sub->needed) {
1822 if (strcmp(idstr, sub->vmsd->name) == 0) {
1823 return sub->vmsd;
1825 sub++;
1827 return NULL;
1830 static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
1831 void *opaque)
1833 while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
1834 char idstr[256];
1835 int ret;
1836 uint8_t version_id, len, size;
1837 const VMStateDescription *sub_vmsd;
1839 len = qemu_peek_byte(f, 1);
1840 if (len < strlen(vmsd->name) + 1) {
1841 /* subsection name has be be "section_name/a" */
1842 return 0;
1844 size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
1845 if (size != len) {
1846 return 0;
1848 idstr[size] = 0;
1850 if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
1851 /* it don't have a valid subsection name */
1852 return 0;
1854 sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
1855 if (sub_vmsd == NULL) {
1856 return -ENOENT;
1858 qemu_file_skip(f, 1); /* subsection */
1859 qemu_file_skip(f, 1); /* len */
1860 qemu_file_skip(f, len); /* idstr */
1861 version_id = qemu_get_be32(f);
1863 ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
1864 if (ret) {
1865 return ret;
1868 return 0;
1871 static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
1872 void *opaque)
1874 const VMStateSubsection *sub = vmsd->subsections;
1876 while (sub && sub->needed) {
1877 if (sub->needed(opaque)) {
1878 const VMStateDescription *vmsd = sub->vmsd;
1879 uint8_t len;
1881 qemu_put_byte(f, QEMU_VM_SUBSECTION);
1882 len = strlen(vmsd->name);
1883 qemu_put_byte(f, len);
1884 qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
1885 qemu_put_be32(f, vmsd->version_id);
1886 vmstate_save_state(f, vmsd, opaque);
1888 sub++;
1892 typedef struct LoadStateEntry {
1893 QLIST_ENTRY(LoadStateEntry) entry;
1894 SaveStateEntry *se;
1895 int section_id;
1896 int version_id;
1897 } LoadStateEntry;
1899 int qemu_loadvm_state(QEMUFile *f)
1901 QLIST_HEAD(, LoadStateEntry) loadvm_handlers =
1902 QLIST_HEAD_INITIALIZER(loadvm_handlers);
1903 LoadStateEntry *le, *new_le;
1904 uint8_t section_type;
1905 unsigned int v;
1906 int ret;
1908 if (qemu_savevm_state_blocked(NULL)) {
1909 return -EINVAL;
1912 v = qemu_get_be32(f);
1913 if (v != QEMU_VM_FILE_MAGIC)
1914 return -EINVAL;
1916 v = qemu_get_be32(f);
1917 if (v == QEMU_VM_FILE_VERSION_COMPAT) {
1918 fprintf(stderr, "SaveVM v2 format is obsolete and don't work anymore\n");
1919 return -ENOTSUP;
1921 if (v != QEMU_VM_FILE_VERSION)
1922 return -ENOTSUP;
1924 while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) {
1925 uint32_t instance_id, version_id, section_id;
1926 SaveStateEntry *se;
1927 char idstr[257];
1928 int len;
1930 switch (section_type) {
1931 case QEMU_VM_SECTION_START:
1932 case QEMU_VM_SECTION_FULL:
1933 /* Read section start */
1934 section_id = qemu_get_be32(f);
1935 len = qemu_get_byte(f);
1936 qemu_get_buffer(f, (uint8_t *)idstr, len);
1937 idstr[len] = 0;
1938 instance_id = qemu_get_be32(f);
1939 version_id = qemu_get_be32(f);
1941 /* Find savevm section */
1942 se = find_se(idstr, instance_id);
1943 if (se == NULL) {
1944 fprintf(stderr, "Unknown savevm section or instance '%s' %d\n", idstr, instance_id);
1945 ret = -EINVAL;
1946 goto out;
1949 /* Validate version */
1950 if (version_id > se->version_id) {
1951 fprintf(stderr, "savevm: unsupported version %d for '%s' v%d\n",
1952 version_id, idstr, se->version_id);
1953 ret = -EINVAL;
1954 goto out;
1957 /* Add entry */
1958 le = g_malloc0(sizeof(*le));
1960 le->se = se;
1961 le->section_id = section_id;
1962 le->version_id = version_id;
1963 QLIST_INSERT_HEAD(&loadvm_handlers, le, entry);
1965 ret = vmstate_load(f, le->se, le->version_id);
1966 if (ret < 0) {
1967 fprintf(stderr, "qemu: warning: error while loading state for instance 0x%x of device '%s'\n",
1968 instance_id, idstr);
1969 goto out;
1971 break;
1972 case QEMU_VM_SECTION_PART:
1973 case QEMU_VM_SECTION_END:
1974 section_id = qemu_get_be32(f);
1976 QLIST_FOREACH(le, &loadvm_handlers, entry) {
1977 if (le->section_id == section_id) {
1978 break;
1981 if (le == NULL) {
1982 fprintf(stderr, "Unknown savevm section %d\n", section_id);
1983 ret = -EINVAL;
1984 goto out;
1987 ret = vmstate_load(f, le->se, le->version_id);
1988 if (ret < 0) {
1989 fprintf(stderr, "qemu: warning: error while loading state section id %d\n",
1990 section_id);
1991 goto out;
1993 break;
1994 default:
1995 fprintf(stderr, "Unknown savevm section type %d\n", section_type);
1996 ret = -EINVAL;
1997 goto out;
2001 cpu_synchronize_all_post_init();
2003 ret = 0;
2005 out:
2006 QLIST_FOREACH_SAFE(le, &loadvm_handlers, entry, new_le) {
2007 QLIST_REMOVE(le, entry);
2008 g_free(le);
2011 if (ret == 0) {
2012 ret = qemu_file_get_error(f);
2015 return ret;
2018 static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
2019 const char *name)
2021 QEMUSnapshotInfo *sn_tab, *sn;
2022 int nb_sns, i, ret;
2024 ret = -ENOENT;
2025 nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2026 if (nb_sns < 0)
2027 return ret;
2028 for(i = 0; i < nb_sns; i++) {
2029 sn = &sn_tab[i];
2030 if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
2031 *sn_info = *sn;
2032 ret = 0;
2033 break;
2036 g_free(sn_tab);
2037 return ret;
2041 * Deletes snapshots of a given name in all opened images.
2043 static int del_existing_snapshots(Monitor *mon, const char *name)
2045 BlockDriverState *bs;
2046 QEMUSnapshotInfo sn1, *snapshot = &sn1;
2047 int ret;
2049 bs = NULL;
2050 while ((bs = bdrv_next(bs))) {
2051 if (bdrv_can_snapshot(bs) &&
2052 bdrv_snapshot_find(bs, snapshot, name) >= 0)
2054 ret = bdrv_snapshot_delete(bs, name);
2055 if (ret < 0) {
2056 monitor_printf(mon,
2057 "Error while deleting snapshot on '%s'\n",
2058 bdrv_get_device_name(bs));
2059 return -1;
2064 return 0;
2067 void do_savevm(Monitor *mon, const QDict *qdict)
2069 BlockDriverState *bs, *bs1;
2070 QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
2071 int ret;
2072 QEMUFile *f;
2073 int saved_vm_running;
2074 uint64_t vm_state_size;
2075 #ifdef _WIN32
2076 struct _timeb tb;
2077 struct tm *ptm;
2078 #else
2079 struct timeval tv;
2080 struct tm tm;
2081 #endif
2082 const char *name = qdict_get_try_str(qdict, "name");
2084 /* Verify if there is a device that doesn't support snapshots and is writable */
2085 bs = NULL;
2086 while ((bs = bdrv_next(bs))) {
2088 if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2089 continue;
2092 if (!bdrv_can_snapshot(bs)) {
2093 monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n",
2094 bdrv_get_device_name(bs));
2095 return;
2099 bs = bdrv_snapshots();
2100 if (!bs) {
2101 monitor_printf(mon, "No block device can accept snapshots\n");
2102 return;
2105 saved_vm_running = runstate_is_running();
2106 vm_stop(RUN_STATE_SAVE_VM);
2108 memset(sn, 0, sizeof(*sn));
2110 /* fill auxiliary fields */
2111 #ifdef _WIN32
2112 _ftime(&tb);
2113 sn->date_sec = tb.time;
2114 sn->date_nsec = tb.millitm * 1000000;
2115 #else
2116 gettimeofday(&tv, NULL);
2117 sn->date_sec = tv.tv_sec;
2118 sn->date_nsec = tv.tv_usec * 1000;
2119 #endif
2120 sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
2122 if (name) {
2123 ret = bdrv_snapshot_find(bs, old_sn, name);
2124 if (ret >= 0) {
2125 pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
2126 pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
2127 } else {
2128 pstrcpy(sn->name, sizeof(sn->name), name);
2130 } else {
2131 #ifdef _WIN32
2132 time_t t = tb.time;
2133 ptm = localtime(&t);
2134 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", ptm);
2135 #else
2136 /* cast below needed for OpenBSD where tv_sec is still 'long' */
2137 localtime_r((const time_t *)&tv.tv_sec, &tm);
2138 strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
2139 #endif
2142 /* Delete old snapshots of the same name */
2143 if (name && del_existing_snapshots(mon, name) < 0) {
2144 goto the_end;
2147 /* save the VM state */
2148 f = qemu_fopen_bdrv(bs, 1);
2149 if (!f) {
2150 monitor_printf(mon, "Could not open VM state file\n");
2151 goto the_end;
2153 ret = qemu_savevm_state(f);
2154 vm_state_size = qemu_ftell(f);
2155 qemu_fclose(f);
2156 if (ret < 0) {
2157 monitor_printf(mon, "Error %d while writing VM\n", ret);
2158 goto the_end;
2161 /* create the snapshots */
2163 bs1 = NULL;
2164 while ((bs1 = bdrv_next(bs1))) {
2165 if (bdrv_can_snapshot(bs1)) {
2166 /* Write VM state size only to the image that contains the state */
2167 sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
2168 ret = bdrv_snapshot_create(bs1, sn);
2169 if (ret < 0) {
2170 monitor_printf(mon, "Error while creating snapshot on '%s'\n",
2171 bdrv_get_device_name(bs1));
2176 the_end:
2177 if (saved_vm_running)
2178 vm_start();
2181 void qmp_xen_save_devices_state(const char *filename, Error **errp)
2183 QEMUFile *f;
2184 int saved_vm_running;
2185 int ret;
2187 saved_vm_running = runstate_is_running();
2188 vm_stop(RUN_STATE_SAVE_VM);
2190 f = qemu_fopen(filename, "wb");
2191 if (!f) {
2192 error_set(errp, QERR_OPEN_FILE_FAILED, filename);
2193 goto the_end;
2195 ret = qemu_save_device_state(f);
2196 qemu_fclose(f);
2197 if (ret < 0) {
2198 error_set(errp, QERR_IO_ERROR);
2201 the_end:
2202 if (saved_vm_running)
2203 vm_start();
2206 int load_vmstate(const char *name)
2208 BlockDriverState *bs, *bs_vm_state;
2209 QEMUSnapshotInfo sn;
2210 QEMUFile *f;
2211 int ret;
2213 bs_vm_state = bdrv_snapshots();
2214 if (!bs_vm_state) {
2215 error_report("No block device supports snapshots");
2216 return -ENOTSUP;
2219 /* Don't even try to load empty VM states */
2220 ret = bdrv_snapshot_find(bs_vm_state, &sn, name);
2221 if (ret < 0) {
2222 return ret;
2223 } else if (sn.vm_state_size == 0) {
2224 error_report("This is a disk-only snapshot. Revert to it offline "
2225 "using qemu-img.");
2226 return -EINVAL;
2229 /* Verify if there is any device that doesn't support snapshots and is
2230 writable and check if the requested snapshot is available too. */
2231 bs = NULL;
2232 while ((bs = bdrv_next(bs))) {
2234 if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
2235 continue;
2238 if (!bdrv_can_snapshot(bs)) {
2239 error_report("Device '%s' is writable but does not support snapshots.",
2240 bdrv_get_device_name(bs));
2241 return -ENOTSUP;
2244 ret = bdrv_snapshot_find(bs, &sn, name);
2245 if (ret < 0) {
2246 error_report("Device '%s' does not have the requested snapshot '%s'",
2247 bdrv_get_device_name(bs), name);
2248 return ret;
2252 /* Flush all IO requests so they don't interfere with the new state. */
2253 bdrv_drain_all();
2255 bs = NULL;
2256 while ((bs = bdrv_next(bs))) {
2257 if (bdrv_can_snapshot(bs)) {
2258 ret = bdrv_snapshot_goto(bs, name);
2259 if (ret < 0) {
2260 error_report("Error %d while activating snapshot '%s' on '%s'",
2261 ret, name, bdrv_get_device_name(bs));
2262 return ret;
2267 /* restore the VM state */
2268 f = qemu_fopen_bdrv(bs_vm_state, 0);
2269 if (!f) {
2270 error_report("Could not open VM state file");
2271 return -EINVAL;
2274 qemu_system_reset(VMRESET_SILENT);
2275 ret = qemu_loadvm_state(f);
2277 qemu_fclose(f);
2278 if (ret < 0) {
2279 error_report("Error %d while loading VM state", ret);
2280 return ret;
2283 return 0;
2286 void do_delvm(Monitor *mon, const QDict *qdict)
2288 BlockDriverState *bs, *bs1;
2289 int ret;
2290 const char *name = qdict_get_str(qdict, "name");
2292 bs = bdrv_snapshots();
2293 if (!bs) {
2294 monitor_printf(mon, "No block device supports snapshots\n");
2295 return;
2298 bs1 = NULL;
2299 while ((bs1 = bdrv_next(bs1))) {
2300 if (bdrv_can_snapshot(bs1)) {
2301 ret = bdrv_snapshot_delete(bs1, name);
2302 if (ret < 0) {
2303 if (ret == -ENOTSUP)
2304 monitor_printf(mon,
2305 "Snapshots not supported on device '%s'\n",
2306 bdrv_get_device_name(bs1));
2307 else
2308 monitor_printf(mon, "Error %d while deleting snapshot on "
2309 "'%s'\n", ret, bdrv_get_device_name(bs1));
2315 void do_info_snapshots(Monitor *mon)
2317 BlockDriverState *bs, *bs1;
2318 QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s;
2319 int nb_sns, i, ret, available;
2320 int total;
2321 int *available_snapshots;
2322 char buf[256];
2324 bs = bdrv_snapshots();
2325 if (!bs) {
2326 monitor_printf(mon, "No available block device supports snapshots\n");
2327 return;
2330 nb_sns = bdrv_snapshot_list(bs, &sn_tab);
2331 if (nb_sns < 0) {
2332 monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns);
2333 return;
2336 if (nb_sns == 0) {
2337 monitor_printf(mon, "There is no snapshot available.\n");
2338 return;
2341 available_snapshots = g_malloc0(sizeof(int) * nb_sns);
2342 total = 0;
2343 for (i = 0; i < nb_sns; i++) {
2344 sn = &sn_tab[i];
2345 available = 1;
2346 bs1 = NULL;
2348 while ((bs1 = bdrv_next(bs1))) {
2349 if (bdrv_can_snapshot(bs1) && bs1 != bs) {
2350 ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str);
2351 if (ret < 0) {
2352 available = 0;
2353 break;
2358 if (available) {
2359 available_snapshots[total] = i;
2360 total++;
2364 if (total > 0) {
2365 monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
2366 for (i = 0; i < total; i++) {
2367 sn = &sn_tab[available_snapshots[i]];
2368 monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
2370 } else {
2371 monitor_printf(mon, "There is no suitable snapshot available\n");
2374 g_free(sn_tab);
2375 g_free(available_snapshots);
2379 void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)
2381 qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK,
2382 memory_region_name(mr), dev);
2385 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev)
2387 /* Nothing do to while the implementation is in RAMBlock */
2390 void vmstate_register_ram_global(MemoryRegion *mr)
2392 vmstate_register_ram(mr, NULL);
2396 page = zrun nzrun
2397 | zrun nzrun page
2399 zrun = length
2401 nzrun = length byte...
2403 length = uleb128 encoded integer
2405 int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen,
2406 uint8_t *dst, int dlen)
2408 uint32_t zrun_len = 0, nzrun_len = 0;
2409 int d = 0, i = 0;
2410 long res, xor;
2411 uint8_t *nzrun_start = NULL;
2413 g_assert(!(((uintptr_t)old_buf | (uintptr_t)new_buf | slen) %
2414 sizeof(long)));
2416 while (i < slen) {
2417 /* overflow */
2418 if (d + 2 > dlen) {
2419 return -1;
2422 /* not aligned to sizeof(long) */
2423 res = (slen - i) % sizeof(long);
2424 while (res && old_buf[i] == new_buf[i]) {
2425 zrun_len++;
2426 i++;
2427 res--;
2430 /* word at a time for speed */
2431 if (!res) {
2432 while (i < slen &&
2433 (*(long *)(old_buf + i)) == (*(long *)(new_buf + i))) {
2434 i += sizeof(long);
2435 zrun_len += sizeof(long);
2438 /* go over the rest */
2439 while (i < slen && old_buf[i] == new_buf[i]) {
2440 zrun_len++;
2441 i++;
2445 /* buffer unchanged */
2446 if (zrun_len == slen) {
2447 return 0;
2450 /* skip last zero run */
2451 if (i == slen) {
2452 return d;
2455 d += uleb128_encode_small(dst + d, zrun_len);
2457 zrun_len = 0;
2458 nzrun_start = new_buf + i;
2460 /* overflow */
2461 if (d + 2 > dlen) {
2462 return -1;
2464 /* not aligned to sizeof(long) */
2465 res = (slen - i) % sizeof(long);
2466 while (res && old_buf[i] != new_buf[i]) {
2467 i++;
2468 nzrun_len++;
2469 res--;
2472 /* word at a time for speed, use of 32-bit long okay */
2473 if (!res) {
2474 /* truncation to 32-bit long okay */
2475 long mask = (long)0x0101010101010101ULL;
2476 while (i < slen) {
2477 xor = *(long *)(old_buf + i) ^ *(long *)(new_buf + i);
2478 if ((xor - mask) & ~xor & (mask << 7)) {
2479 /* found the end of an nzrun within the current long */
2480 while (old_buf[i] != new_buf[i]) {
2481 nzrun_len++;
2482 i++;
2484 break;
2485 } else {
2486 i += sizeof(long);
2487 nzrun_len += sizeof(long);
2492 d += uleb128_encode_small(dst + d, nzrun_len);
2493 /* overflow */
2494 if (d + nzrun_len > dlen) {
2495 return -1;
2497 memcpy(dst + d, nzrun_start, nzrun_len);
2498 d += nzrun_len;
2499 nzrun_len = 0;
2502 return d;
2505 int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen)
2507 int i = 0, d = 0;
2508 int ret;
2509 uint32_t count = 0;
2511 while (i < slen) {
2513 /* zrun */
2514 if ((slen - i) < 2) {
2515 return -1;
2518 ret = uleb128_decode_small(src + i, &count);
2519 if (ret < 0 || (i && !count)) {
2520 return -1;
2522 i += ret;
2523 d += count;
2525 /* overflow */
2526 if (d > dlen) {
2527 return -1;
2530 /* nzrun */
2531 if ((slen - i) < 2) {
2532 return -1;
2535 ret = uleb128_decode_small(src + i, &count);
2536 if (ret < 0 || !count) {
2537 return -1;
2539 i += ret;
2541 /* overflow */
2542 if (d + count > dlen || i + count > slen) {
2543 return -1;
2546 memcpy(dst + d, src + i, count);
2547 d += count;
2548 i += count;
2551 return d;