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24#include "qemu/osdep.h"
25#include <zlib.h>
26#include "qemu-common.h"
27#include "qemu/error-report.h"
28#include "qemu/iov.h"
29#include "migration.h"
30#include "qemu-file.h"
31#include "trace.h"
32
33#define IO_BUF_SIZE 32768
34#define MAX_IOV_SIZE MIN(IOV_MAX, 64)
35
36struct QEMUFile {
37 const QEMUFileOps *ops;
38 const QEMUFileHooks *hooks;
39 void *opaque;
40
41 int64_t bytes_xfer;
42 int64_t xfer_limit;
43
44 int64_t pos;
45
46 int buf_index;
47 int buf_size;
48 uint8_t buf[IO_BUF_SIZE];
49
50 DECLARE_BITMAP(may_free, MAX_IOV_SIZE);
51 struct iovec iov[MAX_IOV_SIZE];
52 unsigned int iovcnt;
53
54 int last_error;
55};
56
57
58
59
60
61int qemu_file_shutdown(QEMUFile *f)
62{
63 if (!f->ops->shut_down) {
64 return -ENOSYS;
65 }
66 return f->ops->shut_down(f->opaque, true, true);
67}
68
69
70
71
72
73QEMUFile *qemu_file_get_return_path(QEMUFile *f)
74{
75 if (!f->ops->get_return_path) {
76 return NULL;
77 }
78 return f->ops->get_return_path(f->opaque);
79}
80
81bool qemu_file_mode_is_not_valid(const char *mode)
82{
83 if (mode == NULL ||
84 (mode[0] != 'r' && mode[0] != 'w') ||
85 mode[1] != 'b' || mode[2] != 0) {
86 fprintf(stderr, "qemu_fopen: Argument validity check failed\n");
87 return true;
88 }
89
90 return false;
91}
92
93QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops)
94{
95 QEMUFile *f;
96
97 f = g_new0(QEMUFile, 1);
98
99 f->opaque = opaque;
100 f->ops = ops;
101 return f;
102}
103
104
105void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks)
106{
107 f->hooks = hooks;
108}
109
110
111
112
113
114
115
116
117int qemu_file_get_error(QEMUFile *f)
118{
119 return f->last_error;
120}
121
122void qemu_file_set_error(QEMUFile *f, int ret)
123{
124 if (f->last_error == 0) {
125 f->last_error = ret;
126 }
127}
128
129bool qemu_file_is_writable(QEMUFile *f)
130{
131 return f->ops->writev_buffer;
132}
133
134static void qemu_iovec_release_ram(QEMUFile *f)
135{
136 struct iovec iov;
137 unsigned long idx;
138
139
140 idx = find_next_bit(f->may_free, f->iovcnt, 0);
141 if (idx >= f->iovcnt) {
142 return;
143 }
144 iov = f->iov[idx];
145
146
147
148
149
150 while ((idx = find_next_bit(f->may_free, f->iovcnt, idx + 1)) < f->iovcnt) {
151
152 if (iov.iov_base + iov.iov_len == f->iov[idx].iov_base) {
153 iov.iov_len += f->iov[idx].iov_len;
154 continue;
155 }
156 if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) {
157 error_report("migrate: madvise DONTNEED failed %p %zd: %s",
158 iov.iov_base, iov.iov_len, strerror(errno));
159 }
160 iov = f->iov[idx];
161 }
162 if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) {
163 error_report("migrate: madvise DONTNEED failed %p %zd: %s",
164 iov.iov_base, iov.iov_len, strerror(errno));
165 }
166 memset(f->may_free, 0, sizeof(f->may_free));
167}
168
169
170
171
172
173
174
175
176void qemu_fflush(QEMUFile *f)
177{
178 ssize_t ret = 0;
179 ssize_t expect = 0;
180
181 if (!qemu_file_is_writable(f)) {
182 return;
183 }
184
185 if (f->iovcnt > 0) {
186 expect = iov_size(f->iov, f->iovcnt);
187 ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos);
188
189 qemu_iovec_release_ram(f);
190 }
191
192 if (ret >= 0) {
193 f->pos += ret;
194 }
195
196
197
198 if (ret != expect) {
199 qemu_file_set_error(f, ret < 0 ? ret : -EIO);
200 }
201 f->buf_index = 0;
202 f->iovcnt = 0;
203}
204
205void ram_control_before_iterate(QEMUFile *f, uint64_t flags)
206{
207 int ret = 0;
208
209 if (f->hooks && f->hooks->before_ram_iterate) {
210 ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL);
211 if (ret < 0) {
212 qemu_file_set_error(f, ret);
213 }
214 }
215}
216
217void ram_control_after_iterate(QEMUFile *f, uint64_t flags)
218{
219 int ret = 0;
220
221 if (f->hooks && f->hooks->after_ram_iterate) {
222 ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL);
223 if (ret < 0) {
224 qemu_file_set_error(f, ret);
225 }
226 }
227}
228
229void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
230{
231 int ret = -EINVAL;
232
233 if (f->hooks && f->hooks->hook_ram_load) {
234 ret = f->hooks->hook_ram_load(f, f->opaque, flags, data);
235 if (ret < 0) {
236 qemu_file_set_error(f, ret);
237 }
238 } else {
239
240
241
242
243 if (flags == RAM_CONTROL_HOOK) {
244 qemu_file_set_error(f, ret);
245 }
246 }
247}
248
249size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
250 ram_addr_t offset, size_t size,
251 uint64_t *bytes_sent)
252{
253 if (f->hooks && f->hooks->save_page) {
254 int ret = f->hooks->save_page(f, f->opaque, block_offset,
255 offset, size, bytes_sent);
256 if (ret != RAM_SAVE_CONTROL_NOT_SUPP) {
257 f->bytes_xfer += size;
258 }
259
260 if (ret != RAM_SAVE_CONTROL_DELAYED &&
261 ret != RAM_SAVE_CONTROL_NOT_SUPP) {
262 if (bytes_sent && *bytes_sent > 0) {
263 qemu_update_position(f, *bytes_sent);
264 } else if (ret < 0) {
265 qemu_file_set_error(f, ret);
266 }
267 }
268
269 return ret;
270 }
271
272 return RAM_SAVE_CONTROL_NOT_SUPP;
273}
274
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281
282
283static ssize_t qemu_fill_buffer(QEMUFile *f)
284{
285 int len;
286 int pending;
287
288 assert(!qemu_file_is_writable(f));
289
290 pending = f->buf_size - f->buf_index;
291 if (pending > 0) {
292 memmove(f->buf, f->buf + f->buf_index, pending);
293 }
294 f->buf_index = 0;
295 f->buf_size = pending;
296
297 len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos,
298 IO_BUF_SIZE - pending);
299 if (len > 0) {
300 f->buf_size += len;
301 f->pos += len;
302 } else if (len == 0) {
303 qemu_file_set_error(f, -EIO);
304 } else if (len != -EAGAIN) {
305 qemu_file_set_error(f, len);
306 }
307
308 return len;
309}
310
311void qemu_update_position(QEMUFile *f, size_t size)
312{
313 f->pos += size;
314}
315
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321
322
323
324int qemu_fclose(QEMUFile *f)
325{
326 int ret;
327 qemu_fflush(f);
328 ret = qemu_file_get_error(f);
329
330 if (f->ops->close) {
331 int ret2 = f->ops->close(f->opaque);
332 if (ret >= 0) {
333 ret = ret2;
334 }
335 }
336
337
338
339 if (f->last_error) {
340 ret = f->last_error;
341 }
342 g_free(f);
343 trace_qemu_file_fclose();
344 return ret;
345}
346
347static void add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size,
348 bool may_free)
349{
350
351 if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base +
352 f->iov[f->iovcnt - 1].iov_len &&
353 may_free == test_bit(f->iovcnt - 1, f->may_free))
354 {
355 f->iov[f->iovcnt - 1].iov_len += size;
356 } else {
357 if (may_free) {
358 set_bit(f->iovcnt, f->may_free);
359 }
360 f->iov[f->iovcnt].iov_base = (uint8_t *)buf;
361 f->iov[f->iovcnt++].iov_len = size;
362 }
363
364 if (f->iovcnt >= MAX_IOV_SIZE) {
365 qemu_fflush(f);
366 }
367}
368
369void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size,
370 bool may_free)
371{
372 if (f->last_error) {
373 return;
374 }
375
376 f->bytes_xfer += size;
377 add_to_iovec(f, buf, size, may_free);
378}
379
380void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size)
381{
382 size_t l;
383
384 if (f->last_error) {
385 return;
386 }
387
388 while (size > 0) {
389 l = IO_BUF_SIZE - f->buf_index;
390 if (l > size) {
391 l = size;
392 }
393 memcpy(f->buf + f->buf_index, buf, l);
394 f->bytes_xfer += l;
395 add_to_iovec(f, f->buf + f->buf_index, l, false);
396 f->buf_index += l;
397 if (f->buf_index == IO_BUF_SIZE) {
398 qemu_fflush(f);
399 }
400 if (qemu_file_get_error(f)) {
401 break;
402 }
403 buf += l;
404 size -= l;
405 }
406}
407
408void qemu_put_byte(QEMUFile *f, int v)
409{
410 if (f->last_error) {
411 return;
412 }
413
414 f->buf[f->buf_index] = v;
415 f->bytes_xfer++;
416 add_to_iovec(f, f->buf + f->buf_index, 1, false);
417 f->buf_index++;
418 if (f->buf_index == IO_BUF_SIZE) {
419 qemu_fflush(f);
420 }
421}
422
423void qemu_file_skip(QEMUFile *f, int size)
424{
425 if (f->buf_index + size <= f->buf_size) {
426 f->buf_index += size;
427 }
428}
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437
438size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset)
439{
440 ssize_t pending;
441 size_t index;
442
443 assert(!qemu_file_is_writable(f));
444 assert(offset < IO_BUF_SIZE);
445 assert(size <= IO_BUF_SIZE - offset);
446
447
448 index = f->buf_index + offset;
449
450 pending = f->buf_size - index;
451
452
453
454
455
456 while (pending < size) {
457 int received = qemu_fill_buffer(f);
458
459 if (received <= 0) {
460 break;
461 }
462
463 index = f->buf_index + offset;
464 pending = f->buf_size - index;
465 }
466
467 if (pending <= 0) {
468 return 0;
469 }
470 if (size > pending) {
471 size = pending;
472 }
473
474 *buf = f->buf + index;
475 return size;
476}
477
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484
485
486size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size)
487{
488 size_t pending = size;
489 size_t done = 0;
490
491 while (pending > 0) {
492 size_t res;
493 uint8_t *src;
494
495 res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0);
496 if (res == 0) {
497 return done;
498 }
499 memcpy(buf, src, res);
500 qemu_file_skip(f, res);
501 buf += res;
502 pending -= res;
503 done += res;
504 }
505 return done;
506}
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527size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size)
528{
529 if (size < IO_BUF_SIZE) {
530 size_t res;
531 uint8_t *src;
532
533 res = qemu_peek_buffer(f, &src, size, 0);
534
535 if (res == size) {
536 qemu_file_skip(f, res);
537 *buf = src;
538 return res;
539 }
540 }
541
542 return qemu_get_buffer(f, *buf, size);
543}
544
545
546
547
548
549int qemu_peek_byte(QEMUFile *f, int offset)
550{
551 int index = f->buf_index + offset;
552
553 assert(!qemu_file_is_writable(f));
554 assert(offset < IO_BUF_SIZE);
555
556 if (index >= f->buf_size) {
557 qemu_fill_buffer(f);
558 index = f->buf_index + offset;
559 if (index >= f->buf_size) {
560 return 0;
561 }
562 }
563 return f->buf[index];
564}
565
566int qemu_get_byte(QEMUFile *f)
567{
568 int result;
569
570 result = qemu_peek_byte(f, 0);
571 qemu_file_skip(f, 1);
572 return result;
573}
574
575int64_t qemu_ftell_fast(QEMUFile *f)
576{
577 int64_t ret = f->pos;
578 int i;
579
580 for (i = 0; i < f->iovcnt; i++) {
581 ret += f->iov[i].iov_len;
582 }
583
584 return ret;
585}
586
587int64_t qemu_ftell(QEMUFile *f)
588{
589 qemu_fflush(f);
590 return f->pos;
591}
592
593int qemu_file_rate_limit(QEMUFile *f)
594{
595 if (qemu_file_get_error(f)) {
596 return 1;
597 }
598 if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) {
599 return 1;
600 }
601 return 0;
602}
603
604int64_t qemu_file_get_rate_limit(QEMUFile *f)
605{
606 return f->xfer_limit;
607}
608
609void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit)
610{
611 f->xfer_limit = limit;
612}
613
614void qemu_file_reset_rate_limit(QEMUFile *f)
615{
616 f->bytes_xfer = 0;
617}
618
619void qemu_put_be16(QEMUFile *f, unsigned int v)
620{
621 qemu_put_byte(f, v >> 8);
622 qemu_put_byte(f, v);
623}
624
625void qemu_put_be32(QEMUFile *f, unsigned int v)
626{
627 qemu_put_byte(f, v >> 24);
628 qemu_put_byte(f, v >> 16);
629 qemu_put_byte(f, v >> 8);
630 qemu_put_byte(f, v);
631}
632
633void qemu_put_be64(QEMUFile *f, uint64_t v)
634{
635 qemu_put_be32(f, v >> 32);
636 qemu_put_be32(f, v);
637}
638
639unsigned int qemu_get_be16(QEMUFile *f)
640{
641 unsigned int v;
642 v = qemu_get_byte(f) << 8;
643 v |= qemu_get_byte(f);
644 return v;
645}
646
647unsigned int qemu_get_be32(QEMUFile *f)
648{
649 unsigned int v;
650 v = (unsigned int)qemu_get_byte(f) << 24;
651 v |= qemu_get_byte(f) << 16;
652 v |= qemu_get_byte(f) << 8;
653 v |= qemu_get_byte(f);
654 return v;
655}
656
657uint64_t qemu_get_be64(QEMUFile *f)
658{
659 uint64_t v;
660 v = (uint64_t)qemu_get_be32(f) << 32;
661 v |= qemu_get_be32(f);
662 return v;
663}
664
665
666static int qemu_compress_data(z_stream *stream, uint8_t *dest, size_t dest_len,
667 const uint8_t *source, size_t source_len)
668{
669 int err;
670
671 err = deflateReset(stream);
672 if (err != Z_OK) {
673 return -1;
674 }
675
676 stream->avail_in = source_len;
677 stream->next_in = (uint8_t *)source;
678 stream->avail_out = dest_len;
679 stream->next_out = dest;
680
681 err = deflate(stream, Z_FINISH);
682 if (err != Z_STREAM_END) {
683 return -1;
684 }
685
686 return stream->next_out - dest;
687}
688
689
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693
694
695
696
697
698ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream,
699 const uint8_t *p, size_t size)
700{
701 ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t);
702
703 if (blen < compressBound(size)) {
704 if (!qemu_file_is_writable(f)) {
705 return -1;
706 }
707 qemu_fflush(f);
708 blen = IO_BUF_SIZE - sizeof(int32_t);
709 if (blen < compressBound(size)) {
710 return -1;
711 }
712 }
713
714 blen = qemu_compress_data(stream, f->buf + f->buf_index + sizeof(int32_t),
715 blen, p, size);
716 if (blen < 0) {
717 return -1;
718 }
719
720 qemu_put_be32(f, blen);
721 if (f->ops->writev_buffer) {
722 add_to_iovec(f, f->buf + f->buf_index, blen, false);
723 }
724 f->buf_index += blen;
725 if (f->buf_index == IO_BUF_SIZE) {
726 qemu_fflush(f);
727 }
728 return blen + sizeof(int32_t);
729}
730
731
732
733
734
735int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src)
736{
737 int len = 0;
738
739 if (f_src->buf_index > 0) {
740 len = f_src->buf_index;
741 qemu_put_buffer(f_des, f_src->buf, f_src->buf_index);
742 f_src->buf_index = 0;
743 f_src->iovcnt = 0;
744 }
745 return len;
746}
747
748
749
750
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754
755size_t qemu_get_counted_string(QEMUFile *f, char buf[256])
756{
757 size_t len = qemu_get_byte(f);
758 size_t res = qemu_get_buffer(f, (uint8_t *)buf, len);
759
760 buf[res] = 0;
761
762 return res == len ? res : 0;
763}
764
765
766
767
768
769void qemu_put_counted_string(QEMUFile *f, const char *str)
770{
771 size_t len = strlen(str);
772
773 assert(len < 256);
774 qemu_put_byte(f, len);
775 qemu_put_buffer(f, (const uint8_t *)str, len);
776}
777
778
779
780
781
782
783
784void qemu_file_set_blocking(QEMUFile *f, bool block)
785{
786 if (f->ops->set_blocking) {
787 f->ops->set_blocking(f->opaque, block);
788 }
789}
790