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Commit | Line | Data |
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9a4ac51f EH |
1 | /* |
2 | * QEMU System Emulator | |
3 | * | |
4 | * Copyright (c) 2003-2008 Fabrice Bellard | |
5 | * | |
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: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
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. | |
23 | */ | |
1393a485 | 24 | #include "qemu/osdep.h" |
44f0eadc | 25 | #include <zlib.h> |
b85ea5fa | 26 | #include "qemu/madvise.h" |
d49b6836 | 27 | #include "qemu/error-report.h" |
093c455a | 28 | #include "qemu/iov.h" |
6666c96a | 29 | #include "migration.h" |
08a0aee1 | 30 | #include "qemu-file.h" |
9013dca5 | 31 | #include "trace.h" |
3d661c8a | 32 | #include "qapi/error.h" |
093c455a | 33 | |
a24939f2 | 34 | #define IO_BUF_SIZE 32768 |
f9919116 | 35 | #define MAX_IOV_SIZE MIN_CONST(IOV_MAX, 64) |
a24939f2 DB |
36 | |
37 | struct QEMUFile { | |
38 | const QEMUFileOps *ops; | |
39 | const QEMUFileHooks *hooks; | |
40 | void *opaque; | |
41 | ||
42 | int64_t bytes_xfer; | |
43 | int64_t xfer_limit; | |
44 | ||
45 | int64_t pos; /* start of buffer when writing, end of buffer | |
46 | when reading */ | |
47 | int buf_index; | |
48 | int buf_size; /* 0 when writing */ | |
49 | uint8_t buf[IO_BUF_SIZE]; | |
50 | ||
53f09a10 | 51 | DECLARE_BITMAP(may_free, MAX_IOV_SIZE); |
a24939f2 DB |
52 | struct iovec iov[MAX_IOV_SIZE]; |
53 | unsigned int iovcnt; | |
54 | ||
55 | int last_error; | |
3d661c8a | 56 | Error *last_error_obj; |
a555b809 JQ |
57 | /* has the file has been shutdown */ |
58 | bool shutdown; | |
c6ad5be7 PX |
59 | /* Whether opaque points to a QIOChannel */ |
60 | bool has_ioc; | |
a24939f2 DB |
61 | }; |
62 | ||
e1a8c9b6 DDAG |
63 | /* |
64 | * Stop a file from being read/written - not all backing files can do this | |
65 | * typically only sockets can. | |
66 | */ | |
67 | int qemu_file_shutdown(QEMUFile *f) | |
68 | { | |
a555b809 JQ |
69 | int ret; |
70 | ||
71 | f->shutdown = true; | |
e1a8c9b6 DDAG |
72 | if (!f->ops->shut_down) { |
73 | return -ENOSYS; | |
74 | } | |
a555b809 JQ |
75 | ret = f->ops->shut_down(f->opaque, true, true, NULL); |
76 | ||
77 | if (!f->last_error) { | |
78 | qemu_file_set_error(f, -EIO); | |
79 | } | |
80 | return ret; | |
e1a8c9b6 DDAG |
81 | } |
82 | ||
adc468e9 DDAG |
83 | /* |
84 | * Result: QEMUFile* for a 'return path' for comms in the opposite direction | |
85 | * NULL if not available | |
86 | */ | |
87 | QEMUFile *qemu_file_get_return_path(QEMUFile *f) | |
88 | { | |
89 | if (!f->ops->get_return_path) { | |
90 | return NULL; | |
91 | } | |
92 | return f->ops->get_return_path(f->opaque); | |
93 | } | |
94 | ||
093c455a EH |
95 | bool qemu_file_mode_is_not_valid(const char *mode) |
96 | { | |
97 | if (mode == NULL || | |
98 | (mode[0] != 'r' && mode[0] != 'w') || | |
99 | mode[1] != 'b' || mode[2] != 0) { | |
100 | fprintf(stderr, "qemu_fopen: Argument validity check failed\n"); | |
101 | return true; | |
102 | } | |
103 | ||
104 | return false; | |
105 | } | |
106 | ||
c6ad5be7 | 107 | QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops, bool has_ioc) |
093c455a EH |
108 | { |
109 | QEMUFile *f; | |
110 | ||
97f3ad35 | 111 | f = g_new0(QEMUFile, 1); |
093c455a EH |
112 | |
113 | f->opaque = opaque; | |
114 | f->ops = ops; | |
c6ad5be7 | 115 | f->has_ioc = has_ioc; |
093c455a EH |
116 | return f; |
117 | } | |
118 | ||
0436e09f DB |
119 | |
120 | void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks) | |
121 | { | |
122 | f->hooks = hooks; | |
123 | } | |
124 | ||
093c455a | 125 | /* |
3d661c8a | 126 | * Get last error for stream f with optional Error* |
093c455a EH |
127 | * |
128 | * Return negative error value if there has been an error on previous | |
129 | * operations, return 0 if no error happened. | |
3d661c8a YK |
130 | * Optional, it returns Error* in errp, but it may be NULL even if return value |
131 | * is not 0. | |
093c455a EH |
132 | * |
133 | */ | |
3d661c8a | 134 | int qemu_file_get_error_obj(QEMUFile *f, Error **errp) |
093c455a | 135 | { |
3d661c8a YK |
136 | if (errp) { |
137 | *errp = f->last_error_obj ? error_copy(f->last_error_obj) : NULL; | |
138 | } | |
093c455a EH |
139 | return f->last_error; |
140 | } | |
141 | ||
3d661c8a YK |
142 | /* |
143 | * Set the last error for stream f with optional Error* | |
144 | */ | |
145 | void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err) | |
093c455a | 146 | { |
3d661c8a | 147 | if (f->last_error == 0 && ret) { |
093c455a | 148 | f->last_error = ret; |
3d661c8a YK |
149 | error_propagate(&f->last_error_obj, err); |
150 | } else if (err) { | |
151 | error_report_err(err); | |
093c455a EH |
152 | } |
153 | } | |
154 | ||
3d661c8a YK |
155 | /* |
156 | * Get last error for stream f | |
157 | * | |
158 | * Return negative error value if there has been an error on previous | |
159 | * operations, return 0 if no error happened. | |
160 | * | |
161 | */ | |
162 | int qemu_file_get_error(QEMUFile *f) | |
163 | { | |
164 | return qemu_file_get_error_obj(f, NULL); | |
165 | } | |
166 | ||
167 | /* | |
168 | * Set the last error for stream f | |
169 | */ | |
170 | void qemu_file_set_error(QEMUFile *f, int ret) | |
171 | { | |
172 | qemu_file_set_error_obj(f, ret, NULL); | |
173 | } | |
174 | ||
e68dd365 | 175 | bool qemu_file_is_writable(QEMUFile *f) |
093c455a | 176 | { |
11808bb0 | 177 | return f->ops->writev_buffer; |
093c455a EH |
178 | } |
179 | ||
53f09a10 PB |
180 | static void qemu_iovec_release_ram(QEMUFile *f) |
181 | { | |
182 | struct iovec iov; | |
183 | unsigned long idx; | |
184 | ||
185 | /* Find and release all the contiguous memory ranges marked as may_free. */ | |
186 | idx = find_next_bit(f->may_free, f->iovcnt, 0); | |
187 | if (idx >= f->iovcnt) { | |
188 | return; | |
189 | } | |
190 | iov = f->iov[idx]; | |
191 | ||
192 | /* The madvise() in the loop is called for iov within a continuous range and | |
193 | * then reinitialize the iov. And in the end, madvise() is called for the | |
194 | * last iov. | |
195 | */ | |
196 | while ((idx = find_next_bit(f->may_free, f->iovcnt, idx + 1)) < f->iovcnt) { | |
197 | /* check for adjacent buffer and coalesce them */ | |
198 | if (iov.iov_base + iov.iov_len == f->iov[idx].iov_base) { | |
199 | iov.iov_len += f->iov[idx].iov_len; | |
200 | continue; | |
201 | } | |
202 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
203 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
204 | iov.iov_base, iov.iov_len, strerror(errno)); | |
205 | } | |
206 | iov = f->iov[idx]; | |
207 | } | |
208 | if (qemu_madvise(iov.iov_base, iov.iov_len, QEMU_MADV_DONTNEED) < 0) { | |
209 | error_report("migrate: madvise DONTNEED failed %p %zd: %s", | |
210 | iov.iov_base, iov.iov_len, strerror(errno)); | |
211 | } | |
212 | memset(f->may_free, 0, sizeof(f->may_free)); | |
213 | } | |
214 | ||
093c455a EH |
215 | /** |
216 | * Flushes QEMUFile buffer | |
217 | * | |
3b348706 DDAG |
218 | * This will flush all pending data. If data was only partially flushed, it |
219 | * will set an error state. | |
093c455a EH |
220 | */ |
221 | void qemu_fflush(QEMUFile *f) | |
222 | { | |
223 | ssize_t ret = 0; | |
baf51e77 | 224 | ssize_t expect = 0; |
3d661c8a | 225 | Error *local_error = NULL; |
093c455a EH |
226 | |
227 | if (!qemu_file_is_writable(f)) { | |
228 | return; | |
229 | } | |
230 | ||
a555b809 JQ |
231 | if (f->shutdown) { |
232 | return; | |
233 | } | |
11808bb0 DB |
234 | if (f->iovcnt > 0) { |
235 | expect = iov_size(f->iov, f->iovcnt); | |
3d661c8a YK |
236 | ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos, |
237 | &local_error); | |
53f09a10 PB |
238 | |
239 | qemu_iovec_release_ram(f); | |
093c455a | 240 | } |
baf51e77 | 241 | |
093c455a EH |
242 | if (ret >= 0) { |
243 | f->pos += ret; | |
244 | } | |
baf51e77 DB |
245 | /* We expect the QEMUFile write impl to send the full |
246 | * data set we requested, so sanity check that. | |
247 | */ | |
248 | if (ret != expect) { | |
3d661c8a | 249 | qemu_file_set_error_obj(f, ret < 0 ? ret : -EIO, local_error); |
baf51e77 | 250 | } |
093c455a EH |
251 | f->buf_index = 0; |
252 | f->iovcnt = 0; | |
093c455a EH |
253 | } |
254 | ||
255 | void ram_control_before_iterate(QEMUFile *f, uint64_t flags) | |
256 | { | |
257 | int ret = 0; | |
258 | ||
0436e09f DB |
259 | if (f->hooks && f->hooks->before_ram_iterate) { |
260 | ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
261 | if (ret < 0) { |
262 | qemu_file_set_error(f, ret); | |
263 | } | |
264 | } | |
265 | } | |
266 | ||
267 | void ram_control_after_iterate(QEMUFile *f, uint64_t flags) | |
268 | { | |
269 | int ret = 0; | |
270 | ||
0436e09f DB |
271 | if (f->hooks && f->hooks->after_ram_iterate) { |
272 | ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL); | |
093c455a EH |
273 | if (ret < 0) { |
274 | qemu_file_set_error(f, ret); | |
275 | } | |
276 | } | |
277 | } | |
278 | ||
632e3a5c | 279 | void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data) |
093c455a EH |
280 | { |
281 | int ret = -EINVAL; | |
282 | ||
0436e09f DB |
283 | if (f->hooks && f->hooks->hook_ram_load) { |
284 | ret = f->hooks->hook_ram_load(f, f->opaque, flags, data); | |
093c455a EH |
285 | if (ret < 0) { |
286 | qemu_file_set_error(f, ret); | |
287 | } | |
288 | } else { | |
632e3a5c DDAG |
289 | /* |
290 | * Hook is a hook specifically requested by the source sending a flag | |
291 | * that expects there to be a hook on the destination. | |
292 | */ | |
293 | if (flags == RAM_CONTROL_HOOK) { | |
294 | qemu_file_set_error(f, ret); | |
295 | } | |
093c455a EH |
296 | } |
297 | } | |
298 | ||
299 | size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, | |
6e1dea46 JQ |
300 | ram_addr_t offset, size_t size, |
301 | uint64_t *bytes_sent) | |
093c455a | 302 | { |
0436e09f DB |
303 | if (f->hooks && f->hooks->save_page) { |
304 | int ret = f->hooks->save_page(f, f->opaque, block_offset, | |
305 | offset, size, bytes_sent); | |
ccb7e1b5 LC |
306 | if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { |
307 | f->bytes_xfer += size; | |
308 | } | |
309 | ||
310 | if (ret != RAM_SAVE_CONTROL_DELAYED && | |
311 | ret != RAM_SAVE_CONTROL_NOT_SUPP) { | |
093c455a EH |
312 | if (bytes_sent && *bytes_sent > 0) { |
313 | qemu_update_position(f, *bytes_sent); | |
314 | } else if (ret < 0) { | |
315 | qemu_file_set_error(f, ret); | |
316 | } | |
317 | } | |
318 | ||
319 | return ret; | |
320 | } | |
321 | ||
322 | return RAM_SAVE_CONTROL_NOT_SUPP; | |
323 | } | |
324 | ||
548f52ea DDAG |
325 | /* |
326 | * Attempt to fill the buffer from the underlying file | |
327 | * Returns the number of bytes read, or negative value for an error. | |
328 | * | |
329 | * Note that it can return a partially full buffer even in a not error/not EOF | |
330 | * case if the underlying file descriptor gives a short read, and that can | |
331 | * happen even on a blocking fd. | |
332 | */ | |
333 | static ssize_t qemu_fill_buffer(QEMUFile *f) | |
093c455a EH |
334 | { |
335 | int len; | |
336 | int pending; | |
3d661c8a | 337 | Error *local_error = NULL; |
093c455a EH |
338 | |
339 | assert(!qemu_file_is_writable(f)); | |
340 | ||
341 | pending = f->buf_size - f->buf_index; | |
342 | if (pending > 0) { | |
343 | memmove(f->buf, f->buf + f->buf_index, pending); | |
344 | } | |
345 | f->buf_index = 0; | |
346 | f->buf_size = pending; | |
347 | ||
a555b809 JQ |
348 | if (f->shutdown) { |
349 | return 0; | |
350 | } | |
351 | ||
093c455a | 352 | len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, |
3d661c8a | 353 | IO_BUF_SIZE - pending, &local_error); |
093c455a EH |
354 | if (len > 0) { |
355 | f->buf_size += len; | |
356 | f->pos += len; | |
357 | } else if (len == 0) { | |
3d661c8a | 358 | qemu_file_set_error_obj(f, -EIO, local_error); |
093c455a | 359 | } else if (len != -EAGAIN) { |
3d661c8a YK |
360 | qemu_file_set_error_obj(f, len, local_error); |
361 | } else { | |
362 | error_free(local_error); | |
093c455a | 363 | } |
548f52ea DDAG |
364 | |
365 | return len; | |
093c455a EH |
366 | } |
367 | ||
093c455a EH |
368 | void qemu_update_position(QEMUFile *f, size_t size) |
369 | { | |
370 | f->pos += size; | |
371 | } | |
372 | ||
373 | /** Closes the file | |
374 | * | |
375 | * Returns negative error value if any error happened on previous operations or | |
376 | * while closing the file. Returns 0 or positive number on success. | |
377 | * | |
378 | * The meaning of return value on success depends on the specific backend | |
379 | * being used. | |
380 | */ | |
381 | int qemu_fclose(QEMUFile *f) | |
382 | { | |
383 | int ret; | |
384 | qemu_fflush(f); | |
385 | ret = qemu_file_get_error(f); | |
386 | ||
387 | if (f->ops->close) { | |
3d661c8a | 388 | int ret2 = f->ops->close(f->opaque, NULL); |
093c455a EH |
389 | if (ret >= 0) { |
390 | ret = ret2; | |
391 | } | |
392 | } | |
393 | /* If any error was spotted before closing, we should report it | |
394 | * instead of the close() return value. | |
395 | */ | |
396 | if (f->last_error) { | |
397 | ret = f->last_error; | |
398 | } | |
3d661c8a | 399 | error_free(f->last_error_obj); |
093c455a | 400 | g_free(f); |
9013dca5 | 401 | trace_qemu_file_fclose(); |
093c455a EH |
402 | return ret; |
403 | } | |
404 | ||
1bf57fb3 WY |
405 | /* |
406 | * Add buf to iovec. Do flush if iovec is full. | |
407 | * | |
408 | * Return values: | |
409 | * 1 iovec is full and flushed | |
410 | * 0 iovec is not flushed | |
411 | * | |
412 | */ | |
413 | static int add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size, | |
414 | bool may_free) | |
093c455a EH |
415 | { |
416 | /* check for adjacent buffer and coalesce them */ | |
417 | if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base + | |
53f09a10 PB |
418 | f->iov[f->iovcnt - 1].iov_len && |
419 | may_free == test_bit(f->iovcnt - 1, f->may_free)) | |
420 | { | |
093c455a EH |
421 | f->iov[f->iovcnt - 1].iov_len += size; |
422 | } else { | |
c00d434a FL |
423 | if (f->iovcnt >= MAX_IOV_SIZE) { |
424 | /* Should only happen if a previous fflush failed */ | |
425 | assert(f->shutdown || !qemu_file_is_writable(f)); | |
426 | return 1; | |
427 | } | |
53f09a10 PB |
428 | if (may_free) { |
429 | set_bit(f->iovcnt, f->may_free); | |
430 | } | |
093c455a EH |
431 | f->iov[f->iovcnt].iov_base = (uint8_t *)buf; |
432 | f->iov[f->iovcnt++].iov_len = size; | |
433 | } | |
434 | ||
435 | if (f->iovcnt >= MAX_IOV_SIZE) { | |
436 | qemu_fflush(f); | |
1bf57fb3 WY |
437 | return 1; |
438 | } | |
439 | ||
440 | return 0; | |
441 | } | |
442 | ||
443 | static void add_buf_to_iovec(QEMUFile *f, size_t len) | |
444 | { | |
445 | if (!add_to_iovec(f, f->buf + f->buf_index, len, false)) { | |
446 | f->buf_index += len; | |
447 | if (f->buf_index == IO_BUF_SIZE) { | |
448 | qemu_fflush(f); | |
449 | } | |
093c455a EH |
450 | } |
451 | } | |
452 | ||
53f09a10 PB |
453 | void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size, |
454 | bool may_free) | |
093c455a | 455 | { |
093c455a EH |
456 | if (f->last_error) { |
457 | return; | |
458 | } | |
459 | ||
460 | f->bytes_xfer += size; | |
53f09a10 | 461 | add_to_iovec(f, buf, size, may_free); |
093c455a EH |
462 | } |
463 | ||
56f3835f | 464 | void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size) |
093c455a | 465 | { |
56f3835f | 466 | size_t l; |
093c455a EH |
467 | |
468 | if (f->last_error) { | |
469 | return; | |
470 | } | |
471 | ||
472 | while (size > 0) { | |
473 | l = IO_BUF_SIZE - f->buf_index; | |
474 | if (l > size) { | |
475 | l = size; | |
476 | } | |
477 | memcpy(f->buf + f->buf_index, buf, l); | |
478 | f->bytes_xfer += l; | |
1bf57fb3 | 479 | add_buf_to_iovec(f, l); |
093c455a EH |
480 | if (qemu_file_get_error(f)) { |
481 | break; | |
482 | } | |
483 | buf += l; | |
484 | size -= l; | |
485 | } | |
486 | } | |
487 | ||
488 | void qemu_put_byte(QEMUFile *f, int v) | |
489 | { | |
490 | if (f->last_error) { | |
491 | return; | |
492 | } | |
493 | ||
494 | f->buf[f->buf_index] = v; | |
495 | f->bytes_xfer++; | |
1bf57fb3 | 496 | add_buf_to_iovec(f, 1); |
093c455a EH |
497 | } |
498 | ||
499 | void qemu_file_skip(QEMUFile *f, int size) | |
500 | { | |
501 | if (f->buf_index + size <= f->buf_size) { | |
502 | f->buf_index += size; | |
503 | } | |
504 | } | |
505 | ||
548f52ea | 506 | /* |
7c1e52ba DDAG |
507 | * Read 'size' bytes from file (at 'offset') without moving the |
508 | * pointer and set 'buf' to point to that data. | |
548f52ea DDAG |
509 | * |
510 | * It will return size bytes unless there was an error, in which case it will | |
511 | * return as many as it managed to read (assuming blocking fd's which | |
512 | * all current QEMUFile are) | |
513 | */ | |
56f3835f | 514 | size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset) |
093c455a | 515 | { |
56f3835f DDAG |
516 | ssize_t pending; |
517 | size_t index; | |
093c455a EH |
518 | |
519 | assert(!qemu_file_is_writable(f)); | |
548f52ea DDAG |
520 | assert(offset < IO_BUF_SIZE); |
521 | assert(size <= IO_BUF_SIZE - offset); | |
093c455a | 522 | |
548f52ea | 523 | /* The 1st byte to read from */ |
093c455a | 524 | index = f->buf_index + offset; |
548f52ea | 525 | /* The number of available bytes starting at index */ |
093c455a | 526 | pending = f->buf_size - index; |
548f52ea DDAG |
527 | |
528 | /* | |
529 | * qemu_fill_buffer might return just a few bytes, even when there isn't | |
530 | * an error, so loop collecting them until we get enough. | |
531 | */ | |
532 | while (pending < size) { | |
533 | int received = qemu_fill_buffer(f); | |
534 | ||
535 | if (received <= 0) { | |
536 | break; | |
537 | } | |
538 | ||
093c455a EH |
539 | index = f->buf_index + offset; |
540 | pending = f->buf_size - index; | |
541 | } | |
542 | ||
543 | if (pending <= 0) { | |
544 | return 0; | |
545 | } | |
546 | if (size > pending) { | |
547 | size = pending; | |
548 | } | |
549 | ||
7c1e52ba | 550 | *buf = f->buf + index; |
093c455a EH |
551 | return size; |
552 | } | |
553 | ||
548f52ea DDAG |
554 | /* |
555 | * Read 'size' bytes of data from the file into buf. | |
556 | * 'size' can be larger than the internal buffer. | |
557 | * | |
558 | * It will return size bytes unless there was an error, in which case it will | |
559 | * return as many as it managed to read (assuming blocking fd's which | |
560 | * all current QEMUFile are) | |
561 | */ | |
56f3835f | 562 | size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size) |
093c455a | 563 | { |
56f3835f DDAG |
564 | size_t pending = size; |
565 | size_t done = 0; | |
093c455a EH |
566 | |
567 | while (pending > 0) { | |
56f3835f | 568 | size_t res; |
7c1e52ba | 569 | uint8_t *src; |
093c455a | 570 | |
7c1e52ba | 571 | res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0); |
093c455a EH |
572 | if (res == 0) { |
573 | return done; | |
574 | } | |
7c1e52ba | 575 | memcpy(buf, src, res); |
093c455a EH |
576 | qemu_file_skip(f, res); |
577 | buf += res; | |
578 | pending -= res; | |
579 | done += res; | |
580 | } | |
581 | return done; | |
582 | } | |
583 | ||
9504fb51 DDAG |
584 | /* |
585 | * Read 'size' bytes of data from the file. | |
586 | * 'size' can be larger than the internal buffer. | |
587 | * | |
588 | * The data: | |
589 | * may be held on an internal buffer (in which case *buf is updated | |
590 | * to point to it) that is valid until the next qemu_file operation. | |
591 | * OR | |
592 | * will be copied to the *buf that was passed in. | |
593 | * | |
594 | * The code tries to avoid the copy if possible. | |
595 | * | |
596 | * It will return size bytes unless there was an error, in which case it will | |
597 | * return as many as it managed to read (assuming blocking fd's which | |
598 | * all current QEMUFile are) | |
599 | * | |
600 | * Note: Since **buf may get changed, the caller should take care to | |
601 | * keep a pointer to the original buffer if it needs to deallocate it. | |
602 | */ | |
603 | size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size) | |
604 | { | |
605 | if (size < IO_BUF_SIZE) { | |
606 | size_t res; | |
1dfafcbd | 607 | uint8_t *src = NULL; |
9504fb51 DDAG |
608 | |
609 | res = qemu_peek_buffer(f, &src, size, 0); | |
610 | ||
611 | if (res == size) { | |
612 | qemu_file_skip(f, res); | |
613 | *buf = src; | |
614 | return res; | |
615 | } | |
616 | } | |
617 | ||
618 | return qemu_get_buffer(f, *buf, size); | |
619 | } | |
620 | ||
548f52ea DDAG |
621 | /* |
622 | * Peeks a single byte from the buffer; this isn't guaranteed to work if | |
623 | * offset leaves a gap after the previous read/peeked data. | |
624 | */ | |
093c455a EH |
625 | int qemu_peek_byte(QEMUFile *f, int offset) |
626 | { | |
627 | int index = f->buf_index + offset; | |
628 | ||
629 | assert(!qemu_file_is_writable(f)); | |
548f52ea | 630 | assert(offset < IO_BUF_SIZE); |
093c455a EH |
631 | |
632 | if (index >= f->buf_size) { | |
633 | qemu_fill_buffer(f); | |
634 | index = f->buf_index + offset; | |
635 | if (index >= f->buf_size) { | |
636 | return 0; | |
637 | } | |
638 | } | |
639 | return f->buf[index]; | |
640 | } | |
641 | ||
642 | int qemu_get_byte(QEMUFile *f) | |
643 | { | |
644 | int result; | |
645 | ||
646 | result = qemu_peek_byte(f, 0); | |
647 | qemu_file_skip(f, 1); | |
648 | return result; | |
649 | } | |
650 | ||
97221400 AG |
651 | int64_t qemu_ftell_fast(QEMUFile *f) |
652 | { | |
653 | int64_t ret = f->pos; | |
654 | int i; | |
655 | ||
11808bb0 DB |
656 | for (i = 0; i < f->iovcnt; i++) { |
657 | ret += f->iov[i].iov_len; | |
97221400 AG |
658 | } |
659 | ||
660 | return ret; | |
661 | } | |
662 | ||
093c455a EH |
663 | int64_t qemu_ftell(QEMUFile *f) |
664 | { | |
665 | qemu_fflush(f); | |
666 | return f->pos; | |
667 | } | |
668 | ||
669 | int qemu_file_rate_limit(QEMUFile *f) | |
670 | { | |
a555b809 JQ |
671 | if (f->shutdown) { |
672 | return 1; | |
673 | } | |
093c455a EH |
674 | if (qemu_file_get_error(f)) { |
675 | return 1; | |
676 | } | |
677 | if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { | |
678 | return 1; | |
679 | } | |
680 | return 0; | |
681 | } | |
682 | ||
683 | int64_t qemu_file_get_rate_limit(QEMUFile *f) | |
684 | { | |
685 | return f->xfer_limit; | |
686 | } | |
687 | ||
688 | void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) | |
689 | { | |
690 | f->xfer_limit = limit; | |
691 | } | |
692 | ||
693 | void qemu_file_reset_rate_limit(QEMUFile *f) | |
694 | { | |
695 | f->bytes_xfer = 0; | |
696 | } | |
697 | ||
5d7d2558 IR |
698 | void qemu_file_update_transfer(QEMUFile *f, int64_t len) |
699 | { | |
700 | f->bytes_xfer += len; | |
701 | } | |
702 | ||
093c455a EH |
703 | void qemu_put_be16(QEMUFile *f, unsigned int v) |
704 | { | |
705 | qemu_put_byte(f, v >> 8); | |
706 | qemu_put_byte(f, v); | |
707 | } | |
708 | ||
709 | void qemu_put_be32(QEMUFile *f, unsigned int v) | |
710 | { | |
711 | qemu_put_byte(f, v >> 24); | |
712 | qemu_put_byte(f, v >> 16); | |
713 | qemu_put_byte(f, v >> 8); | |
714 | qemu_put_byte(f, v); | |
715 | } | |
716 | ||
717 | void qemu_put_be64(QEMUFile *f, uint64_t v) | |
718 | { | |
719 | qemu_put_be32(f, v >> 32); | |
720 | qemu_put_be32(f, v); | |
721 | } | |
722 | ||
723 | unsigned int qemu_get_be16(QEMUFile *f) | |
724 | { | |
725 | unsigned int v; | |
726 | v = qemu_get_byte(f) << 8; | |
727 | v |= qemu_get_byte(f); | |
728 | return v; | |
729 | } | |
730 | ||
731 | unsigned int qemu_get_be32(QEMUFile *f) | |
732 | { | |
733 | unsigned int v; | |
90d6a673 | 734 | v = (unsigned int)qemu_get_byte(f) << 24; |
093c455a EH |
735 | v |= qemu_get_byte(f) << 16; |
736 | v |= qemu_get_byte(f) << 8; | |
737 | v |= qemu_get_byte(f); | |
738 | return v; | |
739 | } | |
740 | ||
741 | uint64_t qemu_get_be64(QEMUFile *f) | |
742 | { | |
743 | uint64_t v; | |
744 | v = (uint64_t)qemu_get_be32(f) << 32; | |
745 | v |= qemu_get_be32(f); | |
746 | return v; | |
747 | } | |
44f0eadc | 748 | |
dcaf446e XG |
749 | /* return the size after compression, or negative value on error */ |
750 | static int qemu_compress_data(z_stream *stream, uint8_t *dest, size_t dest_len, | |
751 | const uint8_t *source, size_t source_len) | |
752 | { | |
753 | int err; | |
754 | ||
755 | err = deflateReset(stream); | |
756 | if (err != Z_OK) { | |
757 | return -1; | |
758 | } | |
759 | ||
760 | stream->avail_in = source_len; | |
761 | stream->next_in = (uint8_t *)source; | |
762 | stream->avail_out = dest_len; | |
763 | stream->next_out = dest; | |
764 | ||
765 | err = deflate(stream, Z_FINISH); | |
766 | if (err != Z_STREAM_END) { | |
767 | return -1; | |
768 | } | |
769 | ||
770 | return stream->next_out - dest; | |
771 | } | |
772 | ||
773 | /* Compress size bytes of data start at p and store the compressed | |
774 | * data to the buffer of f. | |
b3be2896 | 775 | * |
42d24611 WY |
776 | * Since the file is dummy file with empty_ops, return -1 if f has no space to |
777 | * save the compressed data. | |
44f0eadc | 778 | */ |
dcaf446e XG |
779 | ssize_t qemu_put_compression_data(QEMUFile *f, z_stream *stream, |
780 | const uint8_t *p, size_t size) | |
44f0eadc LL |
781 | { |
782 | ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t); | |
783 | ||
784 | if (blen < compressBound(size)) { | |
42d24611 | 785 | return -1; |
44f0eadc | 786 | } |
dcaf446e XG |
787 | |
788 | blen = qemu_compress_data(stream, f->buf + f->buf_index + sizeof(int32_t), | |
789 | blen, p, size); | |
790 | if (blen < 0) { | |
34ab9e97 | 791 | return -1; |
44f0eadc | 792 | } |
34ab9e97 | 793 | |
44f0eadc | 794 | qemu_put_be32(f, blen); |
1bf57fb3 | 795 | add_buf_to_iovec(f, blen); |
44f0eadc LL |
796 | return blen + sizeof(int32_t); |
797 | } | |
798 | ||
799 | /* Put the data in the buffer of f_src to the buffer of f_des, and | |
800 | * then reset the buf_index of f_src to 0. | |
801 | */ | |
802 | ||
803 | int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src) | |
804 | { | |
805 | int len = 0; | |
806 | ||
807 | if (f_src->buf_index > 0) { | |
808 | len = f_src->buf_index; | |
809 | qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); | |
810 | f_src->buf_index = 0; | |
787d134f | 811 | f_src->iovcnt = 0; |
44f0eadc LL |
812 | } |
813 | return len; | |
814 | } | |
b3af1bc9 DDAG |
815 | |
816 | /* | |
817 | * Get a string whose length is determined by a single preceding byte | |
818 | * A preallocated 256 byte buffer must be passed in. | |
819 | * Returns: len on success and a 0 terminated string in the buffer | |
820 | * else 0 | |
821 | * (Note a 0 length string will return 0 either way) | |
822 | */ | |
823 | size_t qemu_get_counted_string(QEMUFile *f, char buf[256]) | |
824 | { | |
825 | size_t len = qemu_get_byte(f); | |
826 | size_t res = qemu_get_buffer(f, (uint8_t *)buf, len); | |
827 | ||
828 | buf[res] = 0; | |
829 | ||
830 | return res == len ? res : 0; | |
831 | } | |
a800cd5c | 832 | |
f0d64cb7 VSO |
833 | /* |
834 | * Put a string with one preceding byte containing its length. The length of | |
835 | * the string should be less than 256. | |
836 | */ | |
837 | void qemu_put_counted_string(QEMUFile *f, const char *str) | |
838 | { | |
839 | size_t len = strlen(str); | |
840 | ||
841 | assert(len < 256); | |
842 | qemu_put_byte(f, len); | |
843 | qemu_put_buffer(f, (const uint8_t *)str, len); | |
844 | } | |
845 | ||
a800cd5c DDAG |
846 | /* |
847 | * Set the blocking state of the QEMUFile. | |
848 | * Note: On some transports the OS only keeps a single blocking state for | |
849 | * both directions, and thus changing the blocking on the main | |
850 | * QEMUFile can also affect the return path. | |
851 | */ | |
852 | void qemu_file_set_blocking(QEMUFile *f, bool block) | |
853 | { | |
06ad5135 | 854 | if (f->ops->set_blocking) { |
3d661c8a | 855 | f->ops->set_blocking(f->opaque, block, NULL); |
a800cd5c DDAG |
856 | } |
857 | } | |
c6ad5be7 PX |
858 | |
859 | /* | |
860 | * Return the ioc object if it's a migration channel. Note: it can return NULL | |
861 | * for callers passing in a non-migration qemufile. E.g. see qemu_fopen_bdrv() | |
862 | * and its usage in e.g. load_snapshot(). So we need to check against NULL | |
863 | * before using it. If without the check, migration_incoming_state_destroy() | |
864 | * could fail for load_snapshot(). | |
865 | */ | |
866 | QIOChannel *qemu_file_get_ioc(QEMUFile *file) | |
867 | { | |
868 | return file->has_ioc ? QIO_CHANNEL(file->opaque) : NULL; | |
869 | } |