Eduardo Habkost | 9a4ac51 | 2014-10-01 14:47:33 -0300 | [diff] [blame] | 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 | */ |
Peter Maydell | 1393a48 | 2016-01-26 18:16:54 +0000 | [diff] [blame] | 24 | #include "qemu/osdep.h" |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 25 | #include <zlib.h> |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 26 | #include "qemu-common.h" |
Markus Armbruster | d49b683 | 2015-03-17 18:29:20 +0100 | [diff] [blame] | 27 | #include "qemu/error-report.h" |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 28 | #include "qemu/iov.h" |
| 29 | #include "qemu/sockets.h" |
Daniel P. Berrange | 10817bf | 2015-09-01 14:48:02 +0100 | [diff] [blame] | 30 | #include "qemu/coroutine.h" |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 31 | #include "migration/migration.h" |
| 32 | #include "migration/qemu-file.h" |
Alexey Kardashevskiy | 9013dca | 2014-03-11 10:42:29 +1100 | [diff] [blame] | 33 | #include "trace.h" |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 34 | |
Daniel P. Berrange | a24939f | 2016-04-27 11:05:13 +0100 | [diff] [blame] | 35 | #define IO_BUF_SIZE 32768 |
| 36 | #define MAX_IOV_SIZE MIN(IOV_MAX, 64) |
| 37 | |
| 38 | struct QEMUFile { |
| 39 | const QEMUFileOps *ops; |
| 40 | const QEMUFileHooks *hooks; |
| 41 | void *opaque; |
| 42 | |
| 43 | int64_t bytes_xfer; |
| 44 | int64_t xfer_limit; |
| 45 | |
| 46 | int64_t pos; /* start of buffer when writing, end of buffer |
| 47 | when reading */ |
| 48 | int buf_index; |
| 49 | int buf_size; /* 0 when writing */ |
| 50 | uint8_t buf[IO_BUF_SIZE]; |
| 51 | |
| 52 | struct iovec iov[MAX_IOV_SIZE]; |
| 53 | unsigned int iovcnt; |
| 54 | |
| 55 | int last_error; |
| 56 | }; |
| 57 | |
Dr. David Alan Gilbert | e1a8c9b | 2015-01-08 11:11:30 +0000 | [diff] [blame] | 58 | /* |
| 59 | * Stop a file from being read/written - not all backing files can do this |
| 60 | * typically only sockets can. |
| 61 | */ |
| 62 | int qemu_file_shutdown(QEMUFile *f) |
| 63 | { |
| 64 | if (!f->ops->shut_down) { |
| 65 | return -ENOSYS; |
| 66 | } |
| 67 | return f->ops->shut_down(f->opaque, true, true); |
| 68 | } |
| 69 | |
Dr. David Alan Gilbert | adc468e | 2015-11-05 18:10:43 +0000 | [diff] [blame] | 70 | /* |
| 71 | * Result: QEMUFile* for a 'return path' for comms in the opposite direction |
| 72 | * NULL if not available |
| 73 | */ |
| 74 | QEMUFile *qemu_file_get_return_path(QEMUFile *f) |
| 75 | { |
| 76 | if (!f->ops->get_return_path) { |
| 77 | return NULL; |
| 78 | } |
| 79 | return f->ops->get_return_path(f->opaque); |
| 80 | } |
| 81 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 82 | bool qemu_file_mode_is_not_valid(const char *mode) |
| 83 | { |
| 84 | if (mode == NULL || |
| 85 | (mode[0] != 'r' && mode[0] != 'w') || |
| 86 | mode[1] != 'b' || mode[2] != 0) { |
| 87 | fprintf(stderr, "qemu_fopen: Argument validity check failed\n"); |
| 88 | return true; |
| 89 | } |
| 90 | |
| 91 | return false; |
| 92 | } |
| 93 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 94 | QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops) |
| 95 | { |
| 96 | QEMUFile *f; |
| 97 | |
Markus Armbruster | 97f3ad3 | 2015-09-14 13:51:31 +0200 | [diff] [blame] | 98 | f = g_new0(QEMUFile, 1); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 99 | |
| 100 | f->opaque = opaque; |
| 101 | f->ops = ops; |
| 102 | return f; |
| 103 | } |
| 104 | |
Daniel P. Berrange | 0436e09 | 2016-04-27 11:04:55 +0100 | [diff] [blame] | 105 | |
| 106 | void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks) |
| 107 | { |
| 108 | f->hooks = hooks; |
| 109 | } |
| 110 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 111 | /* |
| 112 | * Get last error for stream f |
| 113 | * |
| 114 | * Return negative error value if there has been an error on previous |
| 115 | * operations, return 0 if no error happened. |
| 116 | * |
| 117 | */ |
| 118 | int qemu_file_get_error(QEMUFile *f) |
| 119 | { |
| 120 | return f->last_error; |
| 121 | } |
| 122 | |
| 123 | void qemu_file_set_error(QEMUFile *f, int ret) |
| 124 | { |
| 125 | if (f->last_error == 0) { |
| 126 | f->last_error = ret; |
| 127 | } |
| 128 | } |
| 129 | |
Eduardo Habkost | e68dd36 | 2014-10-01 17:34:34 -0300 | [diff] [blame] | 130 | bool qemu_file_is_writable(QEMUFile *f) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 131 | { |
Daniel P. Berrange | 11808bb | 2016-04-27 11:05:17 +0100 | [diff] [blame] | 132 | return f->ops->writev_buffer; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 133 | } |
| 134 | |
| 135 | /** |
| 136 | * Flushes QEMUFile buffer |
| 137 | * |
| 138 | * If there is writev_buffer QEMUFileOps it uses it otherwise uses |
Daniel P. Berrange | baf51e7 | 2016-04-27 11:04:54 +0100 | [diff] [blame] | 139 | * put_buffer ops. This will flush all pending data. If data was |
| 140 | * only partially flushed, it will set an error state. |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 141 | */ |
| 142 | void qemu_fflush(QEMUFile *f) |
| 143 | { |
| 144 | ssize_t ret = 0; |
Daniel P. Berrange | baf51e7 | 2016-04-27 11:04:54 +0100 | [diff] [blame] | 145 | ssize_t expect = 0; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 146 | |
| 147 | if (!qemu_file_is_writable(f)) { |
| 148 | return; |
| 149 | } |
| 150 | |
Daniel P. Berrange | 11808bb | 2016-04-27 11:05:17 +0100 | [diff] [blame] | 151 | if (f->iovcnt > 0) { |
| 152 | expect = iov_size(f->iov, f->iovcnt); |
| 153 | ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 154 | } |
Daniel P. Berrange | baf51e7 | 2016-04-27 11:04:54 +0100 | [diff] [blame] | 155 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 156 | if (ret >= 0) { |
| 157 | f->pos += ret; |
| 158 | } |
Daniel P. Berrange | baf51e7 | 2016-04-27 11:04:54 +0100 | [diff] [blame] | 159 | /* We expect the QEMUFile write impl to send the full |
| 160 | * data set we requested, so sanity check that. |
| 161 | */ |
| 162 | if (ret != expect) { |
| 163 | qemu_file_set_error(f, ret < 0 ? ret : -EIO); |
| 164 | } |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 165 | f->buf_index = 0; |
| 166 | f->iovcnt = 0; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 167 | } |
| 168 | |
| 169 | void ram_control_before_iterate(QEMUFile *f, uint64_t flags) |
| 170 | { |
| 171 | int ret = 0; |
| 172 | |
Daniel P. Berrange | 0436e09 | 2016-04-27 11:04:55 +0100 | [diff] [blame] | 173 | if (f->hooks && f->hooks->before_ram_iterate) { |
| 174 | ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 175 | if (ret < 0) { |
| 176 | qemu_file_set_error(f, ret); |
| 177 | } |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | void ram_control_after_iterate(QEMUFile *f, uint64_t flags) |
| 182 | { |
| 183 | int ret = 0; |
| 184 | |
Daniel P. Berrange | 0436e09 | 2016-04-27 11:04:55 +0100 | [diff] [blame] | 185 | if (f->hooks && f->hooks->after_ram_iterate) { |
| 186 | ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 187 | if (ret < 0) { |
| 188 | qemu_file_set_error(f, ret); |
| 189 | } |
| 190 | } |
| 191 | } |
| 192 | |
Dr. David Alan Gilbert | 632e3a5 | 2015-06-11 18:17:23 +0100 | [diff] [blame] | 193 | void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 194 | { |
| 195 | int ret = -EINVAL; |
| 196 | |
Daniel P. Berrange | 0436e09 | 2016-04-27 11:04:55 +0100 | [diff] [blame] | 197 | if (f->hooks && f->hooks->hook_ram_load) { |
| 198 | ret = f->hooks->hook_ram_load(f, f->opaque, flags, data); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 199 | if (ret < 0) { |
| 200 | qemu_file_set_error(f, ret); |
| 201 | } |
| 202 | } else { |
Dr. David Alan Gilbert | 632e3a5 | 2015-06-11 18:17:23 +0100 | [diff] [blame] | 203 | /* |
| 204 | * Hook is a hook specifically requested by the source sending a flag |
| 205 | * that expects there to be a hook on the destination. |
| 206 | */ |
| 207 | if (flags == RAM_CONTROL_HOOK) { |
| 208 | qemu_file_set_error(f, ret); |
| 209 | } |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 210 | } |
| 211 | } |
| 212 | |
| 213 | size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset, |
Juan Quintela | 6e1dea4 | 2015-02-12 19:02:42 +0100 | [diff] [blame] | 214 | ram_addr_t offset, size_t size, |
| 215 | uint64_t *bytes_sent) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 216 | { |
Daniel P. Berrange | 0436e09 | 2016-04-27 11:04:55 +0100 | [diff] [blame] | 217 | if (f->hooks && f->hooks->save_page) { |
| 218 | int ret = f->hooks->save_page(f, f->opaque, block_offset, |
| 219 | offset, size, bytes_sent); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 220 | |
| 221 | if (ret != RAM_SAVE_CONTROL_DELAYED) { |
| 222 | if (bytes_sent && *bytes_sent > 0) { |
| 223 | qemu_update_position(f, *bytes_sent); |
| 224 | } else if (ret < 0) { |
| 225 | qemu_file_set_error(f, ret); |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | return ret; |
| 230 | } |
| 231 | |
| 232 | return RAM_SAVE_CONTROL_NOT_SUPP; |
| 233 | } |
| 234 | |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 235 | /* |
| 236 | * Attempt to fill the buffer from the underlying file |
| 237 | * Returns the number of bytes read, or negative value for an error. |
| 238 | * |
| 239 | * Note that it can return a partially full buffer even in a not error/not EOF |
| 240 | * case if the underlying file descriptor gives a short read, and that can |
| 241 | * happen even on a blocking fd. |
| 242 | */ |
| 243 | static ssize_t qemu_fill_buffer(QEMUFile *f) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 244 | { |
| 245 | int len; |
| 246 | int pending; |
| 247 | |
| 248 | assert(!qemu_file_is_writable(f)); |
| 249 | |
| 250 | pending = f->buf_size - f->buf_index; |
| 251 | if (pending > 0) { |
| 252 | memmove(f->buf, f->buf + f->buf_index, pending); |
| 253 | } |
| 254 | f->buf_index = 0; |
| 255 | f->buf_size = pending; |
| 256 | |
| 257 | len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos, |
| 258 | IO_BUF_SIZE - pending); |
| 259 | if (len > 0) { |
| 260 | f->buf_size += len; |
| 261 | f->pos += len; |
| 262 | } else if (len == 0) { |
| 263 | qemu_file_set_error(f, -EIO); |
| 264 | } else if (len != -EAGAIN) { |
| 265 | qemu_file_set_error(f, len); |
| 266 | } |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 267 | |
| 268 | return len; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 269 | } |
| 270 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 271 | void qemu_update_position(QEMUFile *f, size_t size) |
| 272 | { |
| 273 | f->pos += size; |
| 274 | } |
| 275 | |
| 276 | /** Closes the file |
| 277 | * |
| 278 | * Returns negative error value if any error happened on previous operations or |
| 279 | * while closing the file. Returns 0 or positive number on success. |
| 280 | * |
| 281 | * The meaning of return value on success depends on the specific backend |
| 282 | * being used. |
| 283 | */ |
| 284 | int qemu_fclose(QEMUFile *f) |
| 285 | { |
| 286 | int ret; |
| 287 | qemu_fflush(f); |
| 288 | ret = qemu_file_get_error(f); |
| 289 | |
| 290 | if (f->ops->close) { |
| 291 | int ret2 = f->ops->close(f->opaque); |
| 292 | if (ret >= 0) { |
| 293 | ret = ret2; |
| 294 | } |
| 295 | } |
| 296 | /* If any error was spotted before closing, we should report it |
| 297 | * instead of the close() return value. |
| 298 | */ |
| 299 | if (f->last_error) { |
| 300 | ret = f->last_error; |
| 301 | } |
| 302 | g_free(f); |
Alexey Kardashevskiy | 9013dca | 2014-03-11 10:42:29 +1100 | [diff] [blame] | 303 | trace_qemu_file_fclose(); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 304 | return ret; |
| 305 | } |
| 306 | |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 307 | static void add_to_iovec(QEMUFile *f, const uint8_t *buf, size_t size) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 308 | { |
| 309 | /* check for adjacent buffer and coalesce them */ |
| 310 | if (f->iovcnt > 0 && buf == f->iov[f->iovcnt - 1].iov_base + |
| 311 | f->iov[f->iovcnt - 1].iov_len) { |
| 312 | f->iov[f->iovcnt - 1].iov_len += size; |
| 313 | } else { |
| 314 | f->iov[f->iovcnt].iov_base = (uint8_t *)buf; |
| 315 | f->iov[f->iovcnt++].iov_len = size; |
| 316 | } |
| 317 | |
| 318 | if (f->iovcnt >= MAX_IOV_SIZE) { |
| 319 | qemu_fflush(f); |
| 320 | } |
| 321 | } |
| 322 | |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 323 | void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, size_t size) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 324 | { |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 325 | if (f->last_error) { |
| 326 | return; |
| 327 | } |
| 328 | |
| 329 | f->bytes_xfer += size; |
| 330 | add_to_iovec(f, buf, size); |
| 331 | } |
| 332 | |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 333 | void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, size_t size) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 334 | { |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 335 | size_t l; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 336 | |
| 337 | if (f->last_error) { |
| 338 | return; |
| 339 | } |
| 340 | |
| 341 | while (size > 0) { |
| 342 | l = IO_BUF_SIZE - f->buf_index; |
| 343 | if (l > size) { |
| 344 | l = size; |
| 345 | } |
| 346 | memcpy(f->buf + f->buf_index, buf, l); |
| 347 | f->bytes_xfer += l; |
Daniel P. Berrange | 11808bb | 2016-04-27 11:05:17 +0100 | [diff] [blame] | 348 | add_to_iovec(f, f->buf + f->buf_index, l); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 349 | f->buf_index += l; |
| 350 | if (f->buf_index == IO_BUF_SIZE) { |
| 351 | qemu_fflush(f); |
| 352 | } |
| 353 | if (qemu_file_get_error(f)) { |
| 354 | break; |
| 355 | } |
| 356 | buf += l; |
| 357 | size -= l; |
| 358 | } |
| 359 | } |
| 360 | |
| 361 | void qemu_put_byte(QEMUFile *f, int v) |
| 362 | { |
| 363 | if (f->last_error) { |
| 364 | return; |
| 365 | } |
| 366 | |
| 367 | f->buf[f->buf_index] = v; |
| 368 | f->bytes_xfer++; |
Daniel P. Berrange | 11808bb | 2016-04-27 11:05:17 +0100 | [diff] [blame] | 369 | add_to_iovec(f, f->buf + f->buf_index, 1); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 370 | f->buf_index++; |
| 371 | if (f->buf_index == IO_BUF_SIZE) { |
| 372 | qemu_fflush(f); |
| 373 | } |
| 374 | } |
| 375 | |
| 376 | void qemu_file_skip(QEMUFile *f, int size) |
| 377 | { |
| 378 | if (f->buf_index + size <= f->buf_size) { |
| 379 | f->buf_index += size; |
| 380 | } |
| 381 | } |
| 382 | |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 383 | /* |
Dr. David Alan Gilbert | 7c1e52b | 2015-05-21 13:24:15 +0100 | [diff] [blame] | 384 | * Read 'size' bytes from file (at 'offset') without moving the |
| 385 | * pointer and set 'buf' to point to that data. |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 386 | * |
| 387 | * It will return size bytes unless there was an error, in which case it will |
| 388 | * return as many as it managed to read (assuming blocking fd's which |
| 389 | * all current QEMUFile are) |
| 390 | */ |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 391 | size_t qemu_peek_buffer(QEMUFile *f, uint8_t **buf, size_t size, size_t offset) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 392 | { |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 393 | ssize_t pending; |
| 394 | size_t index; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 395 | |
| 396 | assert(!qemu_file_is_writable(f)); |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 397 | assert(offset < IO_BUF_SIZE); |
| 398 | assert(size <= IO_BUF_SIZE - offset); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 399 | |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 400 | /* The 1st byte to read from */ |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 401 | index = f->buf_index + offset; |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 402 | /* The number of available bytes starting at index */ |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 403 | pending = f->buf_size - index; |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 404 | |
| 405 | /* |
| 406 | * qemu_fill_buffer might return just a few bytes, even when there isn't |
| 407 | * an error, so loop collecting them until we get enough. |
| 408 | */ |
| 409 | while (pending < size) { |
| 410 | int received = qemu_fill_buffer(f); |
| 411 | |
| 412 | if (received <= 0) { |
| 413 | break; |
| 414 | } |
| 415 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 416 | index = f->buf_index + offset; |
| 417 | pending = f->buf_size - index; |
| 418 | } |
| 419 | |
| 420 | if (pending <= 0) { |
| 421 | return 0; |
| 422 | } |
| 423 | if (size > pending) { |
| 424 | size = pending; |
| 425 | } |
| 426 | |
Dr. David Alan Gilbert | 7c1e52b | 2015-05-21 13:24:15 +0100 | [diff] [blame] | 427 | *buf = f->buf + index; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 428 | return size; |
| 429 | } |
| 430 | |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 431 | /* |
| 432 | * Read 'size' bytes of data from the file into buf. |
| 433 | * 'size' can be larger than the internal buffer. |
| 434 | * |
| 435 | * It will return size bytes unless there was an error, in which case it will |
| 436 | * return as many as it managed to read (assuming blocking fd's which |
| 437 | * all current QEMUFile are) |
| 438 | */ |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 439 | size_t qemu_get_buffer(QEMUFile *f, uint8_t *buf, size_t size) |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 440 | { |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 441 | size_t pending = size; |
| 442 | size_t done = 0; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 443 | |
| 444 | while (pending > 0) { |
Dr. David Alan Gilbert | 56f3835 | 2015-08-13 11:51:34 +0100 | [diff] [blame] | 445 | size_t res; |
Dr. David Alan Gilbert | 7c1e52b | 2015-05-21 13:24:15 +0100 | [diff] [blame] | 446 | uint8_t *src; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 447 | |
Dr. David Alan Gilbert | 7c1e52b | 2015-05-21 13:24:15 +0100 | [diff] [blame] | 448 | res = qemu_peek_buffer(f, &src, MIN(pending, IO_BUF_SIZE), 0); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 449 | if (res == 0) { |
| 450 | return done; |
| 451 | } |
Dr. David Alan Gilbert | 7c1e52b | 2015-05-21 13:24:15 +0100 | [diff] [blame] | 452 | memcpy(buf, src, res); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 453 | qemu_file_skip(f, res); |
| 454 | buf += res; |
| 455 | pending -= res; |
| 456 | done += res; |
| 457 | } |
| 458 | return done; |
| 459 | } |
| 460 | |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 461 | /* |
Dr. David Alan Gilbert | 9504fb5 | 2015-11-05 18:10:35 +0000 | [diff] [blame] | 462 | * Read 'size' bytes of data from the file. |
| 463 | * 'size' can be larger than the internal buffer. |
| 464 | * |
| 465 | * The data: |
| 466 | * may be held on an internal buffer (in which case *buf is updated |
| 467 | * to point to it) that is valid until the next qemu_file operation. |
| 468 | * OR |
| 469 | * will be copied to the *buf that was passed in. |
| 470 | * |
| 471 | * The code tries to avoid the copy if possible. |
| 472 | * |
| 473 | * It will return size bytes unless there was an error, in which case it will |
| 474 | * return as many as it managed to read (assuming blocking fd's which |
| 475 | * all current QEMUFile are) |
| 476 | * |
| 477 | * Note: Since **buf may get changed, the caller should take care to |
| 478 | * keep a pointer to the original buffer if it needs to deallocate it. |
| 479 | */ |
| 480 | size_t qemu_get_buffer_in_place(QEMUFile *f, uint8_t **buf, size_t size) |
| 481 | { |
| 482 | if (size < IO_BUF_SIZE) { |
| 483 | size_t res; |
| 484 | uint8_t *src; |
| 485 | |
| 486 | res = qemu_peek_buffer(f, &src, size, 0); |
| 487 | |
| 488 | if (res == size) { |
| 489 | qemu_file_skip(f, res); |
| 490 | *buf = src; |
| 491 | return res; |
| 492 | } |
| 493 | } |
| 494 | |
| 495 | return qemu_get_buffer(f, *buf, size); |
| 496 | } |
| 497 | |
| 498 | /* |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 499 | * Peeks a single byte from the buffer; this isn't guaranteed to work if |
| 500 | * offset leaves a gap after the previous read/peeked data. |
| 501 | */ |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 502 | int qemu_peek_byte(QEMUFile *f, int offset) |
| 503 | { |
| 504 | int index = f->buf_index + offset; |
| 505 | |
| 506 | assert(!qemu_file_is_writable(f)); |
Dr. David Alan Gilbert | 548f52e | 2014-04-08 15:29:37 +0100 | [diff] [blame] | 507 | assert(offset < IO_BUF_SIZE); |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 508 | |
| 509 | if (index >= f->buf_size) { |
| 510 | qemu_fill_buffer(f); |
| 511 | index = f->buf_index + offset; |
| 512 | if (index >= f->buf_size) { |
| 513 | return 0; |
| 514 | } |
| 515 | } |
| 516 | return f->buf[index]; |
| 517 | } |
| 518 | |
| 519 | int qemu_get_byte(QEMUFile *f) |
| 520 | { |
| 521 | int result; |
| 522 | |
| 523 | result = qemu_peek_byte(f, 0); |
| 524 | qemu_file_skip(f, 1); |
| 525 | return result; |
| 526 | } |
| 527 | |
Alexander Graf | 9722140 | 2015-01-22 15:01:38 +0100 | [diff] [blame] | 528 | int64_t qemu_ftell_fast(QEMUFile *f) |
| 529 | { |
| 530 | int64_t ret = f->pos; |
| 531 | int i; |
| 532 | |
Daniel P. Berrange | 11808bb | 2016-04-27 11:05:17 +0100 | [diff] [blame] | 533 | for (i = 0; i < f->iovcnt; i++) { |
| 534 | ret += f->iov[i].iov_len; |
Alexander Graf | 9722140 | 2015-01-22 15:01:38 +0100 | [diff] [blame] | 535 | } |
| 536 | |
| 537 | return ret; |
| 538 | } |
| 539 | |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 540 | int64_t qemu_ftell(QEMUFile *f) |
| 541 | { |
| 542 | qemu_fflush(f); |
| 543 | return f->pos; |
| 544 | } |
| 545 | |
| 546 | int qemu_file_rate_limit(QEMUFile *f) |
| 547 | { |
| 548 | if (qemu_file_get_error(f)) { |
| 549 | return 1; |
| 550 | } |
| 551 | if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { |
| 552 | return 1; |
| 553 | } |
| 554 | return 0; |
| 555 | } |
| 556 | |
| 557 | int64_t qemu_file_get_rate_limit(QEMUFile *f) |
| 558 | { |
| 559 | return f->xfer_limit; |
| 560 | } |
| 561 | |
| 562 | void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) |
| 563 | { |
| 564 | f->xfer_limit = limit; |
| 565 | } |
| 566 | |
| 567 | void qemu_file_reset_rate_limit(QEMUFile *f) |
| 568 | { |
| 569 | f->bytes_xfer = 0; |
| 570 | } |
| 571 | |
| 572 | void qemu_put_be16(QEMUFile *f, unsigned int v) |
| 573 | { |
| 574 | qemu_put_byte(f, v >> 8); |
| 575 | qemu_put_byte(f, v); |
| 576 | } |
| 577 | |
| 578 | void qemu_put_be32(QEMUFile *f, unsigned int v) |
| 579 | { |
| 580 | qemu_put_byte(f, v >> 24); |
| 581 | qemu_put_byte(f, v >> 16); |
| 582 | qemu_put_byte(f, v >> 8); |
| 583 | qemu_put_byte(f, v); |
| 584 | } |
| 585 | |
| 586 | void qemu_put_be64(QEMUFile *f, uint64_t v) |
| 587 | { |
| 588 | qemu_put_be32(f, v >> 32); |
| 589 | qemu_put_be32(f, v); |
| 590 | } |
| 591 | |
| 592 | unsigned int qemu_get_be16(QEMUFile *f) |
| 593 | { |
| 594 | unsigned int v; |
| 595 | v = qemu_get_byte(f) << 8; |
| 596 | v |= qemu_get_byte(f); |
| 597 | return v; |
| 598 | } |
| 599 | |
| 600 | unsigned int qemu_get_be32(QEMUFile *f) |
| 601 | { |
| 602 | unsigned int v; |
Peter Maydell | 90d6a67 | 2014-12-23 22:26:55 +0000 | [diff] [blame] | 603 | v = (unsigned int)qemu_get_byte(f) << 24; |
Eduardo Habkost | 093c455 | 2013-11-28 12:01:16 -0200 | [diff] [blame] | 604 | v |= qemu_get_byte(f) << 16; |
| 605 | v |= qemu_get_byte(f) << 8; |
| 606 | v |= qemu_get_byte(f); |
| 607 | return v; |
| 608 | } |
| 609 | |
| 610 | uint64_t qemu_get_be64(QEMUFile *f) |
| 611 | { |
| 612 | uint64_t v; |
| 613 | v = (uint64_t)qemu_get_be32(f) << 32; |
| 614 | v |= qemu_get_be32(f); |
| 615 | return v; |
| 616 | } |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 617 | |
Liang Li | b3be289 | 2016-05-05 15:32:54 +0800 | [diff] [blame] | 618 | /* Compress size bytes of data start at p with specific compression |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 619 | * level and store the compressed data to the buffer of f. |
Liang Li | b3be289 | 2016-05-05 15:32:54 +0800 | [diff] [blame] | 620 | * |
| 621 | * When f is not writable, return -1 if f has no space to save the |
| 622 | * compressed data. |
| 623 | * When f is wirtable and it has no space to save the compressed data, |
| 624 | * do fflush first, if f still has no space to save the compressed |
| 625 | * data, return -1. |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 626 | */ |
| 627 | |
| 628 | ssize_t qemu_put_compression_data(QEMUFile *f, const uint8_t *p, size_t size, |
| 629 | int level) |
| 630 | { |
| 631 | ssize_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int32_t); |
| 632 | |
| 633 | if (blen < compressBound(size)) { |
Liang Li | b3be289 | 2016-05-05 15:32:54 +0800 | [diff] [blame] | 634 | if (!qemu_file_is_writable(f)) { |
| 635 | return -1; |
| 636 | } |
| 637 | qemu_fflush(f); |
| 638 | blen = IO_BUF_SIZE - sizeof(int32_t); |
| 639 | if (blen < compressBound(size)) { |
| 640 | return -1; |
| 641 | } |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 642 | } |
| 643 | if (compress2(f->buf + f->buf_index + sizeof(int32_t), (uLongf *)&blen, |
| 644 | (Bytef *)p, size, level) != Z_OK) { |
| 645 | error_report("Compress Failed!"); |
| 646 | return 0; |
| 647 | } |
| 648 | qemu_put_be32(f, blen); |
Liang Li | b3be289 | 2016-05-05 15:32:54 +0800 | [diff] [blame] | 649 | if (f->ops->writev_buffer) { |
| 650 | add_to_iovec(f, f->buf + f->buf_index, blen); |
| 651 | } |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 652 | f->buf_index += blen; |
Liang Li | b3be289 | 2016-05-05 15:32:54 +0800 | [diff] [blame] | 653 | if (f->buf_index == IO_BUF_SIZE) { |
| 654 | qemu_fflush(f); |
| 655 | } |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 656 | return blen + sizeof(int32_t); |
| 657 | } |
| 658 | |
| 659 | /* Put the data in the buffer of f_src to the buffer of f_des, and |
| 660 | * then reset the buf_index of f_src to 0. |
| 661 | */ |
| 662 | |
| 663 | int qemu_put_qemu_file(QEMUFile *f_des, QEMUFile *f_src) |
| 664 | { |
| 665 | int len = 0; |
| 666 | |
| 667 | if (f_src->buf_index > 0) { |
| 668 | len = f_src->buf_index; |
| 669 | qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); |
| 670 | f_src->buf_index = 0; |
Liang Li | 787d134 | 2016-08-09 08:22:26 +0800 | [diff] [blame] | 671 | f_src->iovcnt = 0; |
Liang Li | 44f0ead | 2015-03-23 16:32:19 +0800 | [diff] [blame] | 672 | } |
| 673 | return len; |
| 674 | } |
Dr. David Alan Gilbert | b3af1bc | 2015-05-21 13:24:11 +0100 | [diff] [blame] | 675 | |
| 676 | /* |
| 677 | * Get a string whose length is determined by a single preceding byte |
| 678 | * A preallocated 256 byte buffer must be passed in. |
| 679 | * Returns: len on success and a 0 terminated string in the buffer |
| 680 | * else 0 |
| 681 | * (Note a 0 length string will return 0 either way) |
| 682 | */ |
| 683 | size_t qemu_get_counted_string(QEMUFile *f, char buf[256]) |
| 684 | { |
| 685 | size_t len = qemu_get_byte(f); |
| 686 | size_t res = qemu_get_buffer(f, (uint8_t *)buf, len); |
| 687 | |
| 688 | buf[res] = 0; |
| 689 | |
| 690 | return res == len ? res : 0; |
| 691 | } |
Dr. David Alan Gilbert | a800cd5 | 2015-11-05 18:10:36 +0000 | [diff] [blame] | 692 | |
| 693 | /* |
| 694 | * Set the blocking state of the QEMUFile. |
| 695 | * Note: On some transports the OS only keeps a single blocking state for |
| 696 | * both directions, and thus changing the blocking on the main |
| 697 | * QEMUFile can also affect the return path. |
| 698 | */ |
| 699 | void qemu_file_set_blocking(QEMUFile *f, bool block) |
| 700 | { |
Daniel P. Berrange | 06ad513 | 2016-04-27 11:04:56 +0100 | [diff] [blame] | 701 | if (f->ops->set_blocking) { |
| 702 | f->ops->set_blocking(f->opaque, block); |
Dr. David Alan Gilbert | a800cd5 | 2015-11-05 18:10:36 +0000 | [diff] [blame] | 703 | } |
| 704 | } |