1 /* 2 * QEMU dump 3 * 4 * Copyright Fujitsu, Corp. 2011, 2012 5 * 6 * Authors: 7 * Wen Congyang <wency@cn.fujitsu.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or later. 10 * See the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "qemu/osdep.h" 15 #include "qemu/cutils.h" 16 #include "elf.h" 17 #include "qemu/bswap.h" 18 #include "exec/target_page.h" 19 #include "monitor/monitor.h" 20 #include "sysemu/dump.h" 21 #include "sysemu/runstate.h" 22 #include "sysemu/cpus.h" 23 #include "qapi/error.h" 24 #include "qapi/qapi-commands-dump.h" 25 #include "qapi/qapi-events-dump.h" 26 #include "qapi/qmp/qerror.h" 27 #include "qemu/error-report.h" 28 #include "qemu/main-loop.h" 29 #include "hw/misc/vmcoreinfo.h" 30 #include "migration/blocker.h" 31 #include "hw/core/cpu.h" 32 #include "win_dump.h" 33 34 #include <zlib.h> 35 #ifdef CONFIG_LZO 36 #include <lzo/lzo1x.h> 37 #endif 38 #ifdef CONFIG_SNAPPY 39 #include <snappy-c.h> 40 #endif 41 #ifndef ELF_MACHINE_UNAME 42 #define ELF_MACHINE_UNAME "Unknown" 43 #endif 44 45 #define MAX_GUEST_NOTE_SIZE (1 << 20) /* 1MB should be enough */ 46 47 static Error *dump_migration_blocker; 48 49 #define ELF_NOTE_SIZE(hdr_size, name_size, desc_size) \ 50 ((DIV_ROUND_UP((hdr_size), 4) + \ 51 DIV_ROUND_UP((name_size), 4) + \ 52 DIV_ROUND_UP((desc_size), 4)) * 4) 53 54 static inline bool dump_is_64bit(DumpState *s) 55 { 56 return s->dump_info.d_class == ELFCLASS64; 57 } 58 59 static inline bool dump_has_filter(DumpState *s) 60 { 61 return s->filter_area_length > 0; 62 } 63 64 uint16_t cpu_to_dump16(DumpState *s, uint16_t val) 65 { 66 if (s->dump_info.d_endian == ELFDATA2LSB) { 67 val = cpu_to_le16(val); 68 } else { 69 val = cpu_to_be16(val); 70 } 71 72 return val; 73 } 74 75 uint32_t cpu_to_dump32(DumpState *s, uint32_t val) 76 { 77 if (s->dump_info.d_endian == ELFDATA2LSB) { 78 val = cpu_to_le32(val); 79 } else { 80 val = cpu_to_be32(val); 81 } 82 83 return val; 84 } 85 86 uint64_t cpu_to_dump64(DumpState *s, uint64_t val) 87 { 88 if (s->dump_info.d_endian == ELFDATA2LSB) { 89 val = cpu_to_le64(val); 90 } else { 91 val = cpu_to_be64(val); 92 } 93 94 return val; 95 } 96 97 static int dump_cleanup(DumpState *s) 98 { 99 if (s->dump_info.arch_cleanup_fn) { 100 s->dump_info.arch_cleanup_fn(s); 101 } 102 103 guest_phys_blocks_free(&s->guest_phys_blocks); 104 memory_mapping_list_free(&s->list); 105 close(s->fd); 106 g_free(s->guest_note); 107 g_clear_pointer(&s->string_table_buf, g_array_unref); 108 s->guest_note = NULL; 109 if (s->resume) { 110 if (s->detached) { 111 bql_lock(); 112 } 113 vm_start(); 114 if (s->detached) { 115 bql_unlock(); 116 } 117 } 118 migrate_del_blocker(&dump_migration_blocker); 119 120 return 0; 121 } 122 123 static int fd_write_vmcore(const void *buf, size_t size, void *opaque) 124 { 125 DumpState *s = opaque; 126 size_t written_size; 127 128 written_size = qemu_write_full(s->fd, buf, size); 129 if (written_size != size) { 130 return -errno; 131 } 132 133 return 0; 134 } 135 136 static void prepare_elf64_header(DumpState *s, Elf64_Ehdr *elf_header) 137 { 138 /* 139 * phnum in the elf header is 16 bit, if we have more segments we 140 * set phnum to PN_XNUM and write the real number of segments to a 141 * special section. 142 */ 143 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 144 145 memset(elf_header, 0, sizeof(Elf64_Ehdr)); 146 memcpy(elf_header, ELFMAG, SELFMAG); 147 elf_header->e_ident[EI_CLASS] = ELFCLASS64; 148 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 149 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 150 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 151 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 152 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 153 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 154 elf_header->e_phoff = cpu_to_dump64(s, s->phdr_offset); 155 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); 156 elf_header->e_phnum = cpu_to_dump16(s, phnum); 157 elf_header->e_shoff = cpu_to_dump64(s, s->shdr_offset); 158 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); 159 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 160 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 161 } 162 163 static void prepare_elf32_header(DumpState *s, Elf32_Ehdr *elf_header) 164 { 165 /* 166 * phnum in the elf header is 16 bit, if we have more segments we 167 * set phnum to PN_XNUM and write the real number of segments to a 168 * special section. 169 */ 170 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 171 172 memset(elf_header, 0, sizeof(Elf32_Ehdr)); 173 memcpy(elf_header, ELFMAG, SELFMAG); 174 elf_header->e_ident[EI_CLASS] = ELFCLASS32; 175 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 176 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 177 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 178 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 179 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 180 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 181 elf_header->e_phoff = cpu_to_dump32(s, s->phdr_offset); 182 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); 183 elf_header->e_phnum = cpu_to_dump16(s, phnum); 184 elf_header->e_shoff = cpu_to_dump32(s, s->shdr_offset); 185 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); 186 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 187 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 188 } 189 190 static void write_elf_header(DumpState *s, Error **errp) 191 { 192 Elf32_Ehdr elf32_header; 193 Elf64_Ehdr elf64_header; 194 size_t header_size; 195 void *header_ptr; 196 int ret; 197 198 /* The NULL header and the shstrtab are always defined */ 199 assert(s->shdr_num >= 2); 200 if (dump_is_64bit(s)) { 201 prepare_elf64_header(s, &elf64_header); 202 header_size = sizeof(elf64_header); 203 header_ptr = &elf64_header; 204 } else { 205 prepare_elf32_header(s, &elf32_header); 206 header_size = sizeof(elf32_header); 207 header_ptr = &elf32_header; 208 } 209 210 ret = fd_write_vmcore(header_ptr, header_size, s); 211 if (ret < 0) { 212 error_setg_errno(errp, -ret, "dump: failed to write elf header"); 213 } 214 } 215 216 static void write_elf64_load(DumpState *s, MemoryMapping *memory_mapping, 217 int phdr_index, hwaddr offset, 218 hwaddr filesz, Error **errp) 219 { 220 Elf64_Phdr phdr; 221 int ret; 222 223 memset(&phdr, 0, sizeof(Elf64_Phdr)); 224 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 225 phdr.p_offset = cpu_to_dump64(s, offset); 226 phdr.p_paddr = cpu_to_dump64(s, memory_mapping->phys_addr); 227 phdr.p_filesz = cpu_to_dump64(s, filesz); 228 phdr.p_memsz = cpu_to_dump64(s, memory_mapping->length); 229 phdr.p_vaddr = cpu_to_dump64(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 230 231 assert(memory_mapping->length >= filesz); 232 233 ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); 234 if (ret < 0) { 235 error_setg_errno(errp, -ret, 236 "dump: failed to write program header table"); 237 } 238 } 239 240 static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, 241 int phdr_index, hwaddr offset, 242 hwaddr filesz, Error **errp) 243 { 244 Elf32_Phdr phdr; 245 int ret; 246 247 memset(&phdr, 0, sizeof(Elf32_Phdr)); 248 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 249 phdr.p_offset = cpu_to_dump32(s, offset); 250 phdr.p_paddr = cpu_to_dump32(s, memory_mapping->phys_addr); 251 phdr.p_filesz = cpu_to_dump32(s, filesz); 252 phdr.p_memsz = cpu_to_dump32(s, memory_mapping->length); 253 phdr.p_vaddr = 254 cpu_to_dump32(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 255 256 assert(memory_mapping->length >= filesz); 257 258 ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); 259 if (ret < 0) { 260 error_setg_errno(errp, -ret, 261 "dump: failed to write program header table"); 262 } 263 } 264 265 static void prepare_elf64_phdr_note(DumpState *s, Elf64_Phdr *phdr) 266 { 267 memset(phdr, 0, sizeof(*phdr)); 268 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 269 phdr->p_offset = cpu_to_dump64(s, s->note_offset); 270 phdr->p_paddr = 0; 271 phdr->p_filesz = cpu_to_dump64(s, s->note_size); 272 phdr->p_memsz = cpu_to_dump64(s, s->note_size); 273 phdr->p_vaddr = 0; 274 } 275 276 static inline int cpu_index(CPUState *cpu) 277 { 278 return cpu->cpu_index + 1; 279 } 280 281 static void write_guest_note(WriteCoreDumpFunction f, DumpState *s, 282 Error **errp) 283 { 284 int ret; 285 286 if (s->guest_note) { 287 ret = f(s->guest_note, s->guest_note_size, s); 288 if (ret < 0) { 289 error_setg(errp, "dump: failed to write guest note"); 290 } 291 } 292 } 293 294 static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, 295 Error **errp) 296 { 297 CPUState *cpu; 298 int ret; 299 int id; 300 301 CPU_FOREACH(cpu) { 302 id = cpu_index(cpu); 303 ret = cpu_write_elf64_note(f, cpu, id, s); 304 if (ret < 0) { 305 error_setg(errp, "dump: failed to write elf notes"); 306 return; 307 } 308 } 309 310 CPU_FOREACH(cpu) { 311 ret = cpu_write_elf64_qemunote(f, cpu, s); 312 if (ret < 0) { 313 error_setg(errp, "dump: failed to write CPU status"); 314 return; 315 } 316 } 317 318 write_guest_note(f, s, errp); 319 } 320 321 static void prepare_elf32_phdr_note(DumpState *s, Elf32_Phdr *phdr) 322 { 323 memset(phdr, 0, sizeof(*phdr)); 324 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 325 phdr->p_offset = cpu_to_dump32(s, s->note_offset); 326 phdr->p_paddr = 0; 327 phdr->p_filesz = cpu_to_dump32(s, s->note_size); 328 phdr->p_memsz = cpu_to_dump32(s, s->note_size); 329 phdr->p_vaddr = 0; 330 } 331 332 static void write_elf32_notes(WriteCoreDumpFunction f, DumpState *s, 333 Error **errp) 334 { 335 CPUState *cpu; 336 int ret; 337 int id; 338 339 CPU_FOREACH(cpu) { 340 id = cpu_index(cpu); 341 ret = cpu_write_elf32_note(f, cpu, id, s); 342 if (ret < 0) { 343 error_setg(errp, "dump: failed to write elf notes"); 344 return; 345 } 346 } 347 348 CPU_FOREACH(cpu) { 349 ret = cpu_write_elf32_qemunote(f, cpu, s); 350 if (ret < 0) { 351 error_setg(errp, "dump: failed to write CPU status"); 352 return; 353 } 354 } 355 356 write_guest_note(f, s, errp); 357 } 358 359 static void write_elf_phdr_note(DumpState *s, Error **errp) 360 { 361 Elf32_Phdr phdr32; 362 Elf64_Phdr phdr64; 363 void *phdr; 364 size_t size; 365 int ret; 366 367 if (dump_is_64bit(s)) { 368 prepare_elf64_phdr_note(s, &phdr64); 369 size = sizeof(phdr64); 370 phdr = &phdr64; 371 } else { 372 prepare_elf32_phdr_note(s, &phdr32); 373 size = sizeof(phdr32); 374 phdr = &phdr32; 375 } 376 377 ret = fd_write_vmcore(phdr, size, s); 378 if (ret < 0) { 379 error_setg_errno(errp, -ret, 380 "dump: failed to write program header table"); 381 } 382 } 383 384 static void prepare_elf_section_hdr_zero(DumpState *s) 385 { 386 if (dump_is_64bit(s)) { 387 Elf64_Shdr *shdr64 = s->elf_section_hdrs; 388 389 shdr64->sh_info = cpu_to_dump32(s, s->phdr_num); 390 } else { 391 Elf32_Shdr *shdr32 = s->elf_section_hdrs; 392 393 shdr32->sh_info = cpu_to_dump32(s, s->phdr_num); 394 } 395 } 396 397 static void prepare_elf_section_hdr_string(DumpState *s, void *buff) 398 { 399 uint64_t index = s->string_table_buf->len; 400 const char strtab[] = ".shstrtab"; 401 Elf32_Shdr shdr32 = {}; 402 Elf64_Shdr shdr64 = {}; 403 int shdr_size; 404 void *shdr; 405 406 g_array_append_vals(s->string_table_buf, strtab, sizeof(strtab)); 407 if (dump_is_64bit(s)) { 408 shdr_size = sizeof(Elf64_Shdr); 409 shdr64.sh_type = SHT_STRTAB; 410 shdr64.sh_offset = s->section_offset + s->elf_section_data_size; 411 shdr64.sh_name = index; 412 shdr64.sh_size = s->string_table_buf->len; 413 shdr = &shdr64; 414 } else { 415 shdr_size = sizeof(Elf32_Shdr); 416 shdr32.sh_type = SHT_STRTAB; 417 shdr32.sh_offset = s->section_offset + s->elf_section_data_size; 418 shdr32.sh_name = index; 419 shdr32.sh_size = s->string_table_buf->len; 420 shdr = &shdr32; 421 } 422 memcpy(buff, shdr, shdr_size); 423 } 424 425 static bool prepare_elf_section_hdrs(DumpState *s, Error **errp) 426 { 427 size_t len, sizeof_shdr; 428 void *buff_hdr; 429 430 /* 431 * Section ordering: 432 * - HDR zero 433 * - Arch section hdrs 434 * - String table hdr 435 */ 436 sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); 437 len = sizeof_shdr * s->shdr_num; 438 s->elf_section_hdrs = g_malloc0(len); 439 buff_hdr = s->elf_section_hdrs; 440 441 /* 442 * The first section header is ALWAYS a special initial section 443 * header. 444 * 445 * The header should be 0 with one exception being that if 446 * phdr_num is PN_XNUM then the sh_info field contains the real 447 * number of segment entries. 448 * 449 * As we zero allocate the buffer we will only need to modify 450 * sh_info for the PN_XNUM case. 451 */ 452 if (s->phdr_num >= PN_XNUM) { 453 prepare_elf_section_hdr_zero(s); 454 } 455 buff_hdr += sizeof_shdr; 456 457 /* Add architecture defined section headers */ 458 if (s->dump_info.arch_sections_write_hdr_fn 459 && s->shdr_num > 2) { 460 buff_hdr += s->dump_info.arch_sections_write_hdr_fn(s, buff_hdr); 461 462 if (s->shdr_num >= SHN_LORESERVE) { 463 error_setg_errno(errp, EINVAL, 464 "dump: too many architecture defined sections"); 465 return false; 466 } 467 } 468 469 /* 470 * String table is the last section since strings are added via 471 * arch_sections_write_hdr(). 472 */ 473 prepare_elf_section_hdr_string(s, buff_hdr); 474 return true; 475 } 476 477 static void write_elf_section_headers(DumpState *s, Error **errp) 478 { 479 size_t sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); 480 int ret; 481 482 if (!prepare_elf_section_hdrs(s, errp)) { 483 return; 484 } 485 486 ret = fd_write_vmcore(s->elf_section_hdrs, s->shdr_num * sizeof_shdr, s); 487 if (ret < 0) { 488 error_setg_errno(errp, -ret, "dump: failed to write section headers"); 489 } 490 491 g_free(s->elf_section_hdrs); 492 } 493 494 static void write_elf_sections(DumpState *s, Error **errp) 495 { 496 int ret; 497 498 if (s->elf_section_data_size) { 499 /* Write architecture section data */ 500 ret = fd_write_vmcore(s->elf_section_data, 501 s->elf_section_data_size, s); 502 if (ret < 0) { 503 error_setg_errno(errp, -ret, 504 "dump: failed to write architecture section data"); 505 return; 506 } 507 } 508 509 /* Write string table */ 510 ret = fd_write_vmcore(s->string_table_buf->data, 511 s->string_table_buf->len, s); 512 if (ret < 0) { 513 error_setg_errno(errp, -ret, "dump: failed to write string table data"); 514 } 515 } 516 517 static void write_data(DumpState *s, void *buf, int length, Error **errp) 518 { 519 int ret; 520 521 ret = fd_write_vmcore(buf, length, s); 522 if (ret < 0) { 523 error_setg_errno(errp, -ret, "dump: failed to save memory"); 524 } else { 525 s->written_size += length; 526 } 527 } 528 529 /* write the memory to vmcore. 1 page per I/O. */ 530 static void write_memory(DumpState *s, GuestPhysBlock *block, ram_addr_t start, 531 int64_t size, Error **errp) 532 { 533 ERRP_GUARD(); 534 int64_t i; 535 536 for (i = 0; i < size / s->dump_info.page_size; i++) { 537 write_data(s, block->host_addr + start + i * s->dump_info.page_size, 538 s->dump_info.page_size, errp); 539 if (*errp) { 540 return; 541 } 542 } 543 544 if ((size % s->dump_info.page_size) != 0) { 545 write_data(s, block->host_addr + start + i * s->dump_info.page_size, 546 size % s->dump_info.page_size, errp); 547 if (*errp) { 548 return; 549 } 550 } 551 } 552 553 /* get the memory's offset and size in the vmcore */ 554 static void get_offset_range(hwaddr phys_addr, 555 ram_addr_t mapping_length, 556 DumpState *s, 557 hwaddr *p_offset, 558 hwaddr *p_filesz) 559 { 560 GuestPhysBlock *block; 561 hwaddr offset = s->memory_offset; 562 int64_t size_in_block, start; 563 564 /* When the memory is not stored into vmcore, offset will be -1 */ 565 *p_offset = -1; 566 *p_filesz = 0; 567 568 if (dump_has_filter(s)) { 569 if (phys_addr < s->filter_area_begin || 570 phys_addr >= s->filter_area_begin + s->filter_area_length) { 571 return; 572 } 573 } 574 575 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 576 if (dump_has_filter(s)) { 577 if (block->target_start >= s->filter_area_begin + s->filter_area_length || 578 block->target_end <= s->filter_area_begin) { 579 /* This block is out of the range */ 580 continue; 581 } 582 583 if (s->filter_area_begin <= block->target_start) { 584 start = block->target_start; 585 } else { 586 start = s->filter_area_begin; 587 } 588 589 size_in_block = block->target_end - start; 590 if (s->filter_area_begin + s->filter_area_length < block->target_end) { 591 size_in_block -= block->target_end - (s->filter_area_begin + s->filter_area_length); 592 } 593 } else { 594 start = block->target_start; 595 size_in_block = block->target_end - block->target_start; 596 } 597 598 if (phys_addr >= start && phys_addr < start + size_in_block) { 599 *p_offset = phys_addr - start + offset; 600 601 /* The offset range mapped from the vmcore file must not spill over 602 * the GuestPhysBlock, clamp it. The rest of the mapping will be 603 * zero-filled in memory at load time; see 604 * <http://refspecs.linuxbase.org/elf/gabi4+/ch5.pheader.html>. 605 */ 606 *p_filesz = phys_addr + mapping_length <= start + size_in_block ? 607 mapping_length : 608 size_in_block - (phys_addr - start); 609 return; 610 } 611 612 offset += size_in_block; 613 } 614 } 615 616 static void write_elf_phdr_loads(DumpState *s, Error **errp) 617 { 618 ERRP_GUARD(); 619 hwaddr offset, filesz; 620 MemoryMapping *memory_mapping; 621 uint32_t phdr_index = 1; 622 623 QTAILQ_FOREACH(memory_mapping, &s->list.head, next) { 624 get_offset_range(memory_mapping->phys_addr, 625 memory_mapping->length, 626 s, &offset, &filesz); 627 if (dump_is_64bit(s)) { 628 write_elf64_load(s, memory_mapping, phdr_index++, offset, 629 filesz, errp); 630 } else { 631 write_elf32_load(s, memory_mapping, phdr_index++, offset, 632 filesz, errp); 633 } 634 635 if (*errp) { 636 return; 637 } 638 639 if (phdr_index >= s->phdr_num) { 640 break; 641 } 642 } 643 } 644 645 static void write_elf_notes(DumpState *s, Error **errp) 646 { 647 if (dump_is_64bit(s)) { 648 write_elf64_notes(fd_write_vmcore, s, errp); 649 } else { 650 write_elf32_notes(fd_write_vmcore, s, errp); 651 } 652 } 653 654 /* write elf header, PT_NOTE and elf note to vmcore. */ 655 static void dump_begin(DumpState *s, Error **errp) 656 { 657 ERRP_GUARD(); 658 659 /* 660 * the vmcore's format is: 661 * -------------- 662 * | elf header | 663 * -------------- 664 * | sctn_hdr | 665 * -------------- 666 * | PT_NOTE | 667 * -------------- 668 * | PT_LOAD | 669 * -------------- 670 * | ...... | 671 * -------------- 672 * | PT_LOAD | 673 * -------------- 674 * | elf note | 675 * -------------- 676 * | memory | 677 * -------------- 678 * 679 * we only know where the memory is saved after we write elf note into 680 * vmcore. 681 */ 682 683 /* write elf header to vmcore */ 684 write_elf_header(s, errp); 685 if (*errp) { 686 return; 687 } 688 689 /* write section headers to vmcore */ 690 write_elf_section_headers(s, errp); 691 if (*errp) { 692 return; 693 } 694 695 /* write PT_NOTE to vmcore */ 696 write_elf_phdr_note(s, errp); 697 if (*errp) { 698 return; 699 } 700 701 /* write all PT_LOADs to vmcore */ 702 write_elf_phdr_loads(s, errp); 703 if (*errp) { 704 return; 705 } 706 707 /* write notes to vmcore */ 708 write_elf_notes(s, errp); 709 } 710 711 int64_t dump_filtered_memblock_size(GuestPhysBlock *block, 712 int64_t filter_area_start, 713 int64_t filter_area_length) 714 { 715 int64_t size, left, right; 716 717 /* No filter, return full size */ 718 if (!filter_area_length) { 719 return block->target_end - block->target_start; 720 } 721 722 /* calculate the overlapped region. */ 723 left = MAX(filter_area_start, block->target_start); 724 right = MIN(filter_area_start + filter_area_length, block->target_end); 725 size = right - left; 726 size = size > 0 ? size : 0; 727 728 return size; 729 } 730 731 int64_t dump_filtered_memblock_start(GuestPhysBlock *block, 732 int64_t filter_area_start, 733 int64_t filter_area_length) 734 { 735 if (filter_area_length) { 736 /* return -1 if the block is not within filter area */ 737 if (block->target_start >= filter_area_start + filter_area_length || 738 block->target_end <= filter_area_start) { 739 return -1; 740 } 741 742 if (filter_area_start > block->target_start) { 743 return filter_area_start - block->target_start; 744 } 745 } 746 747 return 0; 748 } 749 750 /* write all memory to vmcore */ 751 static void dump_iterate(DumpState *s, Error **errp) 752 { 753 ERRP_GUARD(); 754 GuestPhysBlock *block; 755 int64_t memblock_size, memblock_start; 756 757 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 758 memblock_start = dump_filtered_memblock_start(block, s->filter_area_begin, s->filter_area_length); 759 if (memblock_start == -1) { 760 continue; 761 } 762 763 memblock_size = dump_filtered_memblock_size(block, s->filter_area_begin, s->filter_area_length); 764 765 /* Write the memory to file */ 766 write_memory(s, block, memblock_start, memblock_size, errp); 767 if (*errp) { 768 return; 769 } 770 } 771 } 772 773 static void dump_end(DumpState *s, Error **errp) 774 { 775 int rc; 776 777 if (s->elf_section_data_size) { 778 s->elf_section_data = g_malloc0(s->elf_section_data_size); 779 } 780 781 /* Adds the architecture defined section data to s->elf_section_data */ 782 if (s->dump_info.arch_sections_write_fn && 783 s->elf_section_data_size) { 784 rc = s->dump_info.arch_sections_write_fn(s, s->elf_section_data); 785 if (rc) { 786 error_setg_errno(errp, rc, 787 "dump: failed to get arch section data"); 788 g_free(s->elf_section_data); 789 return; 790 } 791 } 792 793 /* write sections to vmcore */ 794 write_elf_sections(s, errp); 795 } 796 797 static void create_vmcore(DumpState *s, Error **errp) 798 { 799 ERRP_GUARD(); 800 801 dump_begin(s, errp); 802 if (*errp) { 803 return; 804 } 805 806 /* Iterate over memory and dump it to file */ 807 dump_iterate(s, errp); 808 if (*errp) { 809 return; 810 } 811 812 /* Write the section data */ 813 dump_end(s, errp); 814 } 815 816 static int write_start_flat_header(DumpState *s) 817 { 818 MakedumpfileHeader *mh; 819 int ret = 0; 820 821 if (s->kdump_raw) { 822 return 0; 823 } 824 825 QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER); 826 mh = g_malloc0(MAX_SIZE_MDF_HEADER); 827 828 memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE, 829 MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE)); 830 831 mh->type = cpu_to_be64(TYPE_FLAT_HEADER); 832 mh->version = cpu_to_be64(VERSION_FLAT_HEADER); 833 834 size_t written_size; 835 written_size = qemu_write_full(s->fd, mh, MAX_SIZE_MDF_HEADER); 836 if (written_size != MAX_SIZE_MDF_HEADER) { 837 ret = -1; 838 } 839 840 g_free(mh); 841 return ret; 842 } 843 844 static int write_end_flat_header(DumpState *s) 845 { 846 MakedumpfileDataHeader mdh; 847 848 if (s->kdump_raw) { 849 return 0; 850 } 851 852 mdh.offset = END_FLAG_FLAT_HEADER; 853 mdh.buf_size = END_FLAG_FLAT_HEADER; 854 855 size_t written_size; 856 written_size = qemu_write_full(s->fd, &mdh, sizeof(mdh)); 857 if (written_size != sizeof(mdh)) { 858 return -1; 859 } 860 861 return 0; 862 } 863 864 static int write_buffer(DumpState *s, off_t offset, const void *buf, size_t size) 865 { 866 size_t written_size; 867 MakedumpfileDataHeader mdh; 868 off_t seek_loc; 869 870 if (s->kdump_raw) { 871 seek_loc = lseek(s->fd, offset, SEEK_SET); 872 if (seek_loc == (off_t) -1) { 873 return -1; 874 } 875 } else { 876 mdh.offset = cpu_to_be64(offset); 877 mdh.buf_size = cpu_to_be64(size); 878 879 written_size = qemu_write_full(s->fd, &mdh, sizeof(mdh)); 880 if (written_size != sizeof(mdh)) { 881 return -1; 882 } 883 } 884 885 written_size = qemu_write_full(s->fd, buf, size); 886 if (written_size != size) { 887 return -1; 888 } 889 890 return 0; 891 } 892 893 static int buf_write_note(const void *buf, size_t size, void *opaque) 894 { 895 DumpState *s = opaque; 896 897 /* note_buf is not enough */ 898 if (s->note_buf_offset + size > s->note_size) { 899 return -1; 900 } 901 902 memcpy(s->note_buf + s->note_buf_offset, buf, size); 903 904 s->note_buf_offset += size; 905 906 return 0; 907 } 908 909 /* 910 * This function retrieves various sizes from an elf header. 911 * 912 * @note has to be a valid ELF note. The return sizes are unmodified 913 * (not padded or rounded up to be multiple of 4). 914 */ 915 static void get_note_sizes(DumpState *s, const void *note, 916 uint64_t *note_head_size, 917 uint64_t *name_size, 918 uint64_t *desc_size) 919 { 920 uint64_t note_head_sz; 921 uint64_t name_sz; 922 uint64_t desc_sz; 923 924 if (dump_is_64bit(s)) { 925 const Elf64_Nhdr *hdr = note; 926 note_head_sz = sizeof(Elf64_Nhdr); 927 name_sz = cpu_to_dump64(s, hdr->n_namesz); 928 desc_sz = cpu_to_dump64(s, hdr->n_descsz); 929 } else { 930 const Elf32_Nhdr *hdr = note; 931 note_head_sz = sizeof(Elf32_Nhdr); 932 name_sz = cpu_to_dump32(s, hdr->n_namesz); 933 desc_sz = cpu_to_dump32(s, hdr->n_descsz); 934 } 935 936 if (note_head_size) { 937 *note_head_size = note_head_sz; 938 } 939 if (name_size) { 940 *name_size = name_sz; 941 } 942 if (desc_size) { 943 *desc_size = desc_sz; 944 } 945 } 946 947 static bool note_name_equal(DumpState *s, 948 const uint8_t *note, const char *name) 949 { 950 int len = strlen(name) + 1; 951 uint64_t head_size, name_size; 952 953 get_note_sizes(s, note, &head_size, &name_size, NULL); 954 head_size = ROUND_UP(head_size, 4); 955 956 return name_size == len && memcmp(note + head_size, name, len) == 0; 957 } 958 959 /* write common header, sub header and elf note to vmcore */ 960 static void create_header32(DumpState *s, Error **errp) 961 { 962 ERRP_GUARD(); 963 DiskDumpHeader32 *dh = NULL; 964 KdumpSubHeader32 *kh = NULL; 965 size_t size; 966 uint32_t block_size; 967 uint32_t sub_hdr_size; 968 uint32_t bitmap_blocks; 969 uint32_t status = 0; 970 uint64_t offset_note; 971 972 /* write common header, the version of kdump-compressed format is 6th */ 973 size = sizeof(DiskDumpHeader32); 974 dh = g_malloc0(size); 975 976 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 977 dh->header_version = cpu_to_dump32(s, 6); 978 block_size = s->dump_info.page_size; 979 dh->block_size = cpu_to_dump32(s, block_size); 980 sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size; 981 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 982 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 983 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 984 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 985 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 986 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 987 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 988 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 989 990 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 991 status |= DUMP_DH_COMPRESSED_ZLIB; 992 } 993 #ifdef CONFIG_LZO 994 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 995 status |= DUMP_DH_COMPRESSED_LZO; 996 } 997 #endif 998 #ifdef CONFIG_SNAPPY 999 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 1000 status |= DUMP_DH_COMPRESSED_SNAPPY; 1001 } 1002 #endif 1003 dh->status = cpu_to_dump32(s, status); 1004 1005 if (write_buffer(s, 0, dh, size) < 0) { 1006 error_setg(errp, "dump: failed to write disk dump header"); 1007 goto out; 1008 } 1009 1010 /* write sub header */ 1011 size = sizeof(KdumpSubHeader32); 1012 kh = g_malloc0(size); 1013 1014 /* 64bit max_mapnr_64 */ 1015 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1016 kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base); 1017 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1018 1019 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1020 if (s->guest_note && 1021 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1022 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1023 1024 get_note_sizes(s, s->guest_note, 1025 &hsize, &name_size, &size_vmcoreinfo_desc); 1026 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1027 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1028 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1029 kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc); 1030 } 1031 1032 kh->offset_note = cpu_to_dump64(s, offset_note); 1033 kh->note_size = cpu_to_dump32(s, s->note_size); 1034 1035 if (write_buffer(s, DISKDUMP_HEADER_BLOCKS * 1036 block_size, kh, size) < 0) { 1037 error_setg(errp, "dump: failed to write kdump sub header"); 1038 goto out; 1039 } 1040 1041 /* write note */ 1042 s->note_buf = g_malloc0(s->note_size); 1043 s->note_buf_offset = 0; 1044 1045 /* use s->note_buf to store notes temporarily */ 1046 write_elf32_notes(buf_write_note, s, errp); 1047 if (*errp) { 1048 goto out; 1049 } 1050 if (write_buffer(s, offset_note, s->note_buf, 1051 s->note_size) < 0) { 1052 error_setg(errp, "dump: failed to write notes"); 1053 goto out; 1054 } 1055 1056 /* get offset of dump_bitmap */ 1057 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1058 block_size; 1059 1060 /* get offset of page */ 1061 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1062 block_size; 1063 1064 out: 1065 g_free(dh); 1066 g_free(kh); 1067 g_free(s->note_buf); 1068 } 1069 1070 /* write common header, sub header and elf note to vmcore */ 1071 static void create_header64(DumpState *s, Error **errp) 1072 { 1073 ERRP_GUARD(); 1074 DiskDumpHeader64 *dh = NULL; 1075 KdumpSubHeader64 *kh = NULL; 1076 size_t size; 1077 uint32_t block_size; 1078 uint32_t sub_hdr_size; 1079 uint32_t bitmap_blocks; 1080 uint32_t status = 0; 1081 uint64_t offset_note; 1082 1083 /* write common header, the version of kdump-compressed format is 6th */ 1084 size = sizeof(DiskDumpHeader64); 1085 dh = g_malloc0(size); 1086 1087 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 1088 dh->header_version = cpu_to_dump32(s, 6); 1089 block_size = s->dump_info.page_size; 1090 dh->block_size = cpu_to_dump32(s, block_size); 1091 sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size; 1092 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 1093 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 1094 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 1095 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 1096 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 1097 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 1098 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 1099 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 1100 1101 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 1102 status |= DUMP_DH_COMPRESSED_ZLIB; 1103 } 1104 #ifdef CONFIG_LZO 1105 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 1106 status |= DUMP_DH_COMPRESSED_LZO; 1107 } 1108 #endif 1109 #ifdef CONFIG_SNAPPY 1110 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 1111 status |= DUMP_DH_COMPRESSED_SNAPPY; 1112 } 1113 #endif 1114 dh->status = cpu_to_dump32(s, status); 1115 1116 if (write_buffer(s, 0, dh, size) < 0) { 1117 error_setg(errp, "dump: failed to write disk dump header"); 1118 goto out; 1119 } 1120 1121 /* write sub header */ 1122 size = sizeof(KdumpSubHeader64); 1123 kh = g_malloc0(size); 1124 1125 /* 64bit max_mapnr_64 */ 1126 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1127 kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base); 1128 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1129 1130 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1131 if (s->guest_note && 1132 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1133 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1134 1135 get_note_sizes(s, s->guest_note, 1136 &hsize, &name_size, &size_vmcoreinfo_desc); 1137 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1138 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1139 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1140 kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc); 1141 } 1142 1143 kh->offset_note = cpu_to_dump64(s, offset_note); 1144 kh->note_size = cpu_to_dump64(s, s->note_size); 1145 1146 if (write_buffer(s, DISKDUMP_HEADER_BLOCKS * 1147 block_size, kh, size) < 0) { 1148 error_setg(errp, "dump: failed to write kdump sub header"); 1149 goto out; 1150 } 1151 1152 /* write note */ 1153 s->note_buf = g_malloc0(s->note_size); 1154 s->note_buf_offset = 0; 1155 1156 /* use s->note_buf to store notes temporarily */ 1157 write_elf64_notes(buf_write_note, s, errp); 1158 if (*errp) { 1159 goto out; 1160 } 1161 1162 if (write_buffer(s, offset_note, s->note_buf, 1163 s->note_size) < 0) { 1164 error_setg(errp, "dump: failed to write notes"); 1165 goto out; 1166 } 1167 1168 /* get offset of dump_bitmap */ 1169 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1170 block_size; 1171 1172 /* get offset of page */ 1173 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1174 block_size; 1175 1176 out: 1177 g_free(dh); 1178 g_free(kh); 1179 g_free(s->note_buf); 1180 } 1181 1182 static void write_dump_header(DumpState *s, Error **errp) 1183 { 1184 if (dump_is_64bit(s)) { 1185 create_header64(s, errp); 1186 } else { 1187 create_header32(s, errp); 1188 } 1189 } 1190 1191 static size_t dump_bitmap_get_bufsize(DumpState *s) 1192 { 1193 return s->dump_info.page_size; 1194 } 1195 1196 /* 1197 * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be 1198 * rewritten, so if need to set the first bit, set last_pfn and pfn to 0. 1199 * set_dump_bitmap will always leave the recently set bit un-sync. And setting 1200 * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into 1201 * vmcore, ie. synchronizing un-sync bit into vmcore. 1202 */ 1203 static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value, 1204 uint8_t *buf, DumpState *s) 1205 { 1206 off_t old_offset, new_offset; 1207 off_t offset_bitmap1, offset_bitmap2; 1208 uint32_t byte, bit; 1209 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1210 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1211 1212 /* should not set the previous place */ 1213 assert(last_pfn <= pfn); 1214 1215 /* 1216 * if the bit needed to be set is not cached in buf, flush the data in buf 1217 * to vmcore firstly. 1218 * making new_offset be bigger than old_offset can also sync remained data 1219 * into vmcore. 1220 */ 1221 old_offset = bitmap_bufsize * (last_pfn / bits_per_buf); 1222 new_offset = bitmap_bufsize * (pfn / bits_per_buf); 1223 1224 while (old_offset < new_offset) { 1225 /* calculate the offset and write dump_bitmap */ 1226 offset_bitmap1 = s->offset_dump_bitmap + old_offset; 1227 if (write_buffer(s, offset_bitmap1, buf, 1228 bitmap_bufsize) < 0) { 1229 return -1; 1230 } 1231 1232 /* dump level 1 is chosen, so 1st and 2nd bitmap are same */ 1233 offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap + 1234 old_offset; 1235 if (write_buffer(s, offset_bitmap2, buf, 1236 bitmap_bufsize) < 0) { 1237 return -1; 1238 } 1239 1240 memset(buf, 0, bitmap_bufsize); 1241 old_offset += bitmap_bufsize; 1242 } 1243 1244 /* get the exact place of the bit in the buf, and set it */ 1245 byte = (pfn % bits_per_buf) / CHAR_BIT; 1246 bit = (pfn % bits_per_buf) % CHAR_BIT; 1247 if (value) { 1248 buf[byte] |= 1u << bit; 1249 } else { 1250 buf[byte] &= ~(1u << bit); 1251 } 1252 1253 return 0; 1254 } 1255 1256 static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr) 1257 { 1258 int target_page_shift = ctz32(s->dump_info.page_size); 1259 1260 return (addr >> target_page_shift) - ARCH_PFN_OFFSET; 1261 } 1262 1263 static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn) 1264 { 1265 int target_page_shift = ctz32(s->dump_info.page_size); 1266 1267 return (pfn + ARCH_PFN_OFFSET) << target_page_shift; 1268 } 1269 1270 /* 1271 * Return the page frame number and the page content in *bufptr. bufptr can be 1272 * NULL. If not NULL, *bufptr must contains a target page size of pre-allocated 1273 * memory. This is not necessarily the memory returned. 1274 */ 1275 static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr, 1276 uint8_t **bufptr, DumpState *s) 1277 { 1278 GuestPhysBlock *block = *blockptr; 1279 uint32_t page_size = s->dump_info.page_size; 1280 uint8_t *buf = NULL, *hbuf; 1281 hwaddr addr; 1282 1283 /* block == NULL means the start of the iteration */ 1284 if (!block) { 1285 block = QTAILQ_FIRST(&s->guest_phys_blocks.head); 1286 *blockptr = block; 1287 addr = block->target_start; 1288 *pfnptr = dump_paddr_to_pfn(s, addr); 1289 } else { 1290 *pfnptr += 1; 1291 addr = dump_pfn_to_paddr(s, *pfnptr); 1292 } 1293 assert(block != NULL); 1294 1295 while (1) { 1296 if (addr >= block->target_start && addr < block->target_end) { 1297 size_t n = MIN(block->target_end - addr, page_size - addr % page_size); 1298 hbuf = block->host_addr + (addr - block->target_start); 1299 if (!buf) { 1300 if (n == page_size) { 1301 /* this is a whole target page, go for it */ 1302 assert(addr % page_size == 0); 1303 buf = hbuf; 1304 break; 1305 } else if (bufptr) { 1306 assert(*bufptr); 1307 buf = *bufptr; 1308 memset(buf, 0, page_size); 1309 } else { 1310 return true; 1311 } 1312 } 1313 1314 memcpy(buf + addr % page_size, hbuf, n); 1315 addr += n; 1316 if (addr % page_size == 0 || addr >= block->target_end) { 1317 /* we filled up the page or the current block is finished */ 1318 break; 1319 } 1320 } else { 1321 /* the next page is in the next block */ 1322 *blockptr = block = QTAILQ_NEXT(block, next); 1323 if (!block) { 1324 break; 1325 } 1326 1327 addr = block->target_start; 1328 /* are we still in the same page? */ 1329 if (dump_paddr_to_pfn(s, addr) != *pfnptr) { 1330 if (buf) { 1331 /* no, but we already filled something earlier, return it */ 1332 break; 1333 } else { 1334 /* else continue from there */ 1335 *pfnptr = dump_paddr_to_pfn(s, addr); 1336 } 1337 } 1338 } 1339 } 1340 1341 if (bufptr) { 1342 *bufptr = buf; 1343 } 1344 1345 return buf != NULL; 1346 } 1347 1348 static void write_dump_bitmap(DumpState *s, Error **errp) 1349 { 1350 int ret = 0; 1351 uint64_t last_pfn, pfn; 1352 void *dump_bitmap_buf; 1353 size_t num_dumpable; 1354 GuestPhysBlock *block_iter = NULL; 1355 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1356 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1357 1358 /* dump_bitmap_buf is used to store dump_bitmap temporarily */ 1359 dump_bitmap_buf = g_malloc0(bitmap_bufsize); 1360 1361 num_dumpable = 0; 1362 last_pfn = 0; 1363 1364 /* 1365 * exam memory page by page, and set the bit in dump_bitmap corresponded 1366 * to the existing page. 1367 */ 1368 while (get_next_page(&block_iter, &pfn, NULL, s)) { 1369 ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s); 1370 if (ret < 0) { 1371 error_setg(errp, "dump: failed to set dump_bitmap"); 1372 goto out; 1373 } 1374 1375 last_pfn = pfn; 1376 num_dumpable++; 1377 } 1378 1379 /* 1380 * set_dump_bitmap will always leave the recently set bit un-sync. Here we 1381 * set the remaining bits from last_pfn to the end of the bitmap buffer to 1382 * 0. With those set, the un-sync bit will be synchronized into the vmcore. 1383 */ 1384 if (num_dumpable > 0) { 1385 ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false, 1386 dump_bitmap_buf, s); 1387 if (ret < 0) { 1388 error_setg(errp, "dump: failed to sync dump_bitmap"); 1389 goto out; 1390 } 1391 } 1392 1393 /* number of dumpable pages that will be dumped later */ 1394 s->num_dumpable = num_dumpable; 1395 1396 out: 1397 g_free(dump_bitmap_buf); 1398 } 1399 1400 static void prepare_data_cache(DataCache *data_cache, DumpState *s, 1401 off_t offset) 1402 { 1403 data_cache->state = s; 1404 data_cache->data_size = 0; 1405 data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s); 1406 data_cache->buf = g_malloc0(data_cache->buf_size); 1407 data_cache->offset = offset; 1408 } 1409 1410 static int write_cache(DataCache *dc, const void *buf, size_t size, 1411 bool flag_sync) 1412 { 1413 /* 1414 * dc->buf_size should not be less than size, otherwise dc will never be 1415 * enough 1416 */ 1417 assert(size <= dc->buf_size); 1418 1419 /* 1420 * if flag_sync is set, synchronize data in dc->buf into vmcore. 1421 * otherwise check if the space is enough for caching data in buf, if not, 1422 * write the data in dc->buf to dc->state->fd and reset dc->buf 1423 */ 1424 if ((!flag_sync && dc->data_size + size > dc->buf_size) || 1425 (flag_sync && dc->data_size > 0)) { 1426 if (write_buffer(dc->state, dc->offset, dc->buf, dc->data_size) < 0) { 1427 return -1; 1428 } 1429 1430 dc->offset += dc->data_size; 1431 dc->data_size = 0; 1432 } 1433 1434 if (!flag_sync) { 1435 memcpy(dc->buf + dc->data_size, buf, size); 1436 dc->data_size += size; 1437 } 1438 1439 return 0; 1440 } 1441 1442 static void free_data_cache(DataCache *data_cache) 1443 { 1444 g_free(data_cache->buf); 1445 } 1446 1447 static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress) 1448 { 1449 switch (flag_compress) { 1450 case DUMP_DH_COMPRESSED_ZLIB: 1451 return compressBound(page_size); 1452 1453 case DUMP_DH_COMPRESSED_LZO: 1454 /* 1455 * LZO will expand incompressible data by a little amount. Please check 1456 * the following URL to see the expansion calculation: 1457 * http://www.oberhumer.com/opensource/lzo/lzofaq.php 1458 */ 1459 return page_size + page_size / 16 + 64 + 3; 1460 1461 #ifdef CONFIG_SNAPPY 1462 case DUMP_DH_COMPRESSED_SNAPPY: 1463 return snappy_max_compressed_length(page_size); 1464 #endif 1465 } 1466 return 0; 1467 } 1468 1469 static void write_dump_pages(DumpState *s, Error **errp) 1470 { 1471 int ret = 0; 1472 DataCache page_desc, page_data; 1473 size_t len_buf_out, size_out; 1474 #ifdef CONFIG_LZO 1475 lzo_bytep wrkmem = NULL; 1476 #endif 1477 uint8_t *buf_out = NULL; 1478 off_t offset_desc, offset_data; 1479 PageDescriptor pd, pd_zero; 1480 uint8_t *buf; 1481 GuestPhysBlock *block_iter = NULL; 1482 uint64_t pfn_iter; 1483 g_autofree uint8_t *page = NULL; 1484 1485 /* get offset of page_desc and page_data in dump file */ 1486 offset_desc = s->offset_page; 1487 offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable; 1488 1489 prepare_data_cache(&page_desc, s, offset_desc); 1490 prepare_data_cache(&page_data, s, offset_data); 1491 1492 /* prepare buffer to store compressed data */ 1493 len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress); 1494 assert(len_buf_out != 0); 1495 1496 #ifdef CONFIG_LZO 1497 wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS); 1498 #endif 1499 1500 buf_out = g_malloc(len_buf_out); 1501 1502 /* 1503 * init zero page's page_desc and page_data, because every zero page 1504 * uses the same page_data 1505 */ 1506 pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size); 1507 pd_zero.flags = cpu_to_dump32(s, 0); 1508 pd_zero.offset = cpu_to_dump64(s, offset_data); 1509 pd_zero.page_flags = cpu_to_dump64(s, 0); 1510 buf = g_malloc0(s->dump_info.page_size); 1511 ret = write_cache(&page_data, buf, s->dump_info.page_size, false); 1512 g_free(buf); 1513 if (ret < 0) { 1514 error_setg(errp, "dump: failed to write page data (zero page)"); 1515 goto out; 1516 } 1517 1518 offset_data += s->dump_info.page_size; 1519 page = g_malloc(s->dump_info.page_size); 1520 1521 /* 1522 * dump memory to vmcore page by page. zero page will all be resided in the 1523 * first page of page section 1524 */ 1525 for (buf = page; get_next_page(&block_iter, &pfn_iter, &buf, s); buf = page) { 1526 /* check zero page */ 1527 if (buffer_is_zero(buf, s->dump_info.page_size)) { 1528 ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor), 1529 false); 1530 if (ret < 0) { 1531 error_setg(errp, "dump: failed to write page desc"); 1532 goto out; 1533 } 1534 } else { 1535 /* 1536 * not zero page, then: 1537 * 1. compress the page 1538 * 2. write the compressed page into the cache of page_data 1539 * 3. get page desc of the compressed page and write it into the 1540 * cache of page_desc 1541 * 1542 * only one compression format will be used here, for 1543 * s->flag_compress is set. But when compression fails to work, 1544 * we fall back to save in plaintext. 1545 */ 1546 size_out = len_buf_out; 1547 if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) && 1548 (compress2(buf_out, (uLongf *)&size_out, buf, 1549 s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) && 1550 (size_out < s->dump_info.page_size)) { 1551 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB); 1552 pd.size = cpu_to_dump32(s, size_out); 1553 1554 ret = write_cache(&page_data, buf_out, size_out, false); 1555 if (ret < 0) { 1556 error_setg(errp, "dump: failed to write page data"); 1557 goto out; 1558 } 1559 #ifdef CONFIG_LZO 1560 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) && 1561 (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out, 1562 (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) && 1563 (size_out < s->dump_info.page_size)) { 1564 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO); 1565 pd.size = cpu_to_dump32(s, size_out); 1566 1567 ret = write_cache(&page_data, buf_out, size_out, false); 1568 if (ret < 0) { 1569 error_setg(errp, "dump: failed to write page data"); 1570 goto out; 1571 } 1572 #endif 1573 #ifdef CONFIG_SNAPPY 1574 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) && 1575 (snappy_compress((char *)buf, s->dump_info.page_size, 1576 (char *)buf_out, &size_out) == SNAPPY_OK) && 1577 (size_out < s->dump_info.page_size)) { 1578 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY); 1579 pd.size = cpu_to_dump32(s, size_out); 1580 1581 ret = write_cache(&page_data, buf_out, size_out, false); 1582 if (ret < 0) { 1583 error_setg(errp, "dump: failed to write page data"); 1584 goto out; 1585 } 1586 #endif 1587 } else { 1588 /* 1589 * fall back to save in plaintext, size_out should be 1590 * assigned the target's page size 1591 */ 1592 pd.flags = cpu_to_dump32(s, 0); 1593 size_out = s->dump_info.page_size; 1594 pd.size = cpu_to_dump32(s, size_out); 1595 1596 ret = write_cache(&page_data, buf, 1597 s->dump_info.page_size, false); 1598 if (ret < 0) { 1599 error_setg(errp, "dump: failed to write page data"); 1600 goto out; 1601 } 1602 } 1603 1604 /* get and write page desc here */ 1605 pd.page_flags = cpu_to_dump64(s, 0); 1606 pd.offset = cpu_to_dump64(s, offset_data); 1607 offset_data += size_out; 1608 1609 ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false); 1610 if (ret < 0) { 1611 error_setg(errp, "dump: failed to write page desc"); 1612 goto out; 1613 } 1614 } 1615 s->written_size += s->dump_info.page_size; 1616 } 1617 1618 ret = write_cache(&page_desc, NULL, 0, true); 1619 if (ret < 0) { 1620 error_setg(errp, "dump: failed to sync cache for page_desc"); 1621 goto out; 1622 } 1623 ret = write_cache(&page_data, NULL, 0, true); 1624 if (ret < 0) { 1625 error_setg(errp, "dump: failed to sync cache for page_data"); 1626 goto out; 1627 } 1628 1629 out: 1630 free_data_cache(&page_desc); 1631 free_data_cache(&page_data); 1632 1633 #ifdef CONFIG_LZO 1634 g_free(wrkmem); 1635 #endif 1636 1637 g_free(buf_out); 1638 } 1639 1640 static void create_kdump_vmcore(DumpState *s, Error **errp) 1641 { 1642 ERRP_GUARD(); 1643 int ret; 1644 1645 /* 1646 * the kdump-compressed format is: 1647 * File offset 1648 * +------------------------------------------+ 0x0 1649 * | main header (struct disk_dump_header) | 1650 * |------------------------------------------+ block 1 1651 * | sub header (struct kdump_sub_header) | 1652 * |------------------------------------------+ block 2 1653 * | 1st-dump_bitmap | 1654 * |------------------------------------------+ block 2 + X blocks 1655 * | 2nd-dump_bitmap | (aligned by block) 1656 * |------------------------------------------+ block 2 + 2 * X blocks 1657 * | page desc for pfn 0 (struct page_desc) | (aligned by block) 1658 * | page desc for pfn 1 (struct page_desc) | 1659 * | : | 1660 * |------------------------------------------| (not aligned by block) 1661 * | page data (pfn 0) | 1662 * | page data (pfn 1) | 1663 * | : | 1664 * +------------------------------------------+ 1665 */ 1666 1667 ret = write_start_flat_header(s); 1668 if (ret < 0) { 1669 error_setg(errp, "dump: failed to write start flat header"); 1670 return; 1671 } 1672 1673 write_dump_header(s, errp); 1674 if (*errp) { 1675 return; 1676 } 1677 1678 write_dump_bitmap(s, errp); 1679 if (*errp) { 1680 return; 1681 } 1682 1683 write_dump_pages(s, errp); 1684 if (*errp) { 1685 return; 1686 } 1687 1688 ret = write_end_flat_header(s); 1689 if (ret < 0) { 1690 error_setg(errp, "dump: failed to write end flat header"); 1691 return; 1692 } 1693 } 1694 1695 static void get_max_mapnr(DumpState *s) 1696 { 1697 GuestPhysBlock *last_block; 1698 1699 last_block = QTAILQ_LAST(&s->guest_phys_blocks.head); 1700 s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end); 1701 } 1702 1703 static DumpState dump_state_global = { .status = DUMP_STATUS_NONE }; 1704 1705 static void dump_state_prepare(DumpState *s) 1706 { 1707 /* zero the struct, setting status to active */ 1708 *s = (DumpState) { .status = DUMP_STATUS_ACTIVE }; 1709 } 1710 1711 bool qemu_system_dump_in_progress(void) 1712 { 1713 DumpState *state = &dump_state_global; 1714 return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE); 1715 } 1716 1717 /* 1718 * calculate total size of memory to be dumped (taking filter into 1719 * account.) 1720 */ 1721 static int64_t dump_calculate_size(DumpState *s) 1722 { 1723 GuestPhysBlock *block; 1724 int64_t total = 0; 1725 1726 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 1727 total += dump_filtered_memblock_size(block, 1728 s->filter_area_begin, 1729 s->filter_area_length); 1730 } 1731 1732 return total; 1733 } 1734 1735 static void vmcoreinfo_update_phys_base(DumpState *s) 1736 { 1737 uint64_t size, note_head_size, name_size, phys_base; 1738 char **lines; 1739 uint8_t *vmci; 1740 size_t i; 1741 1742 if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1743 return; 1744 } 1745 1746 get_note_sizes(s, s->guest_note, ¬e_head_size, &name_size, &size); 1747 note_head_size = ROUND_UP(note_head_size, 4); 1748 1749 vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4); 1750 *(vmci + size) = '\0'; 1751 1752 lines = g_strsplit((char *)vmci, "\n", -1); 1753 for (i = 0; lines[i]; i++) { 1754 const char *prefix = NULL; 1755 1756 if (s->dump_info.d_machine == EM_X86_64) { 1757 prefix = "NUMBER(phys_base)="; 1758 } else if (s->dump_info.d_machine == EM_AARCH64) { 1759 prefix = "NUMBER(PHYS_OFFSET)="; 1760 } 1761 1762 if (prefix && g_str_has_prefix(lines[i], prefix)) { 1763 if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16, 1764 &phys_base) < 0) { 1765 warn_report("Failed to read %s", prefix); 1766 } else { 1767 s->dump_info.phys_base = phys_base; 1768 } 1769 break; 1770 } 1771 } 1772 1773 g_strfreev(lines); 1774 } 1775 1776 static void dump_init(DumpState *s, int fd, bool has_format, 1777 DumpGuestMemoryFormat format, bool paging, bool has_filter, 1778 int64_t begin, int64_t length, bool kdump_raw, 1779 Error **errp) 1780 { 1781 ERRP_GUARD(); 1782 VMCoreInfoState *vmci = vmcoreinfo_find(); 1783 CPUState *cpu; 1784 int nr_cpus; 1785 int ret; 1786 1787 s->has_format = has_format; 1788 s->format = format; 1789 s->written_size = 0; 1790 s->kdump_raw = kdump_raw; 1791 1792 /* kdump-compressed is conflict with paging and filter */ 1793 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1794 assert(!paging && !has_filter); 1795 } 1796 1797 if (runstate_is_running()) { 1798 vm_stop(RUN_STATE_SAVE_VM); 1799 s->resume = true; 1800 } else { 1801 s->resume = false; 1802 } 1803 1804 /* If we use KVM, we should synchronize the registers before we get dump 1805 * info or physmap info. 1806 */ 1807 cpu_synchronize_all_states(); 1808 nr_cpus = 0; 1809 CPU_FOREACH(cpu) { 1810 nr_cpus++; 1811 } 1812 1813 s->fd = fd; 1814 if (has_filter && !length) { 1815 error_setg(errp, "parameter 'length' expects a non-zero size"); 1816 goto cleanup; 1817 } 1818 s->filter_area_begin = begin; 1819 s->filter_area_length = length; 1820 1821 /* First index is 0, it's the special null name */ 1822 s->string_table_buf = g_array_new(FALSE, TRUE, 1); 1823 /* 1824 * Allocate the null name, due to the clearing option set to true 1825 * it will be 0. 1826 */ 1827 g_array_set_size(s->string_table_buf, 1); 1828 1829 memory_mapping_list_init(&s->list); 1830 1831 guest_phys_blocks_init(&s->guest_phys_blocks); 1832 guest_phys_blocks_append(&s->guest_phys_blocks); 1833 s->total_size = dump_calculate_size(s); 1834 #ifdef DEBUG_DUMP_GUEST_MEMORY 1835 fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size); 1836 #endif 1837 1838 /* it does not make sense to dump non-existent memory */ 1839 if (!s->total_size) { 1840 error_setg(errp, "dump: no guest memory to dump"); 1841 goto cleanup; 1842 } 1843 1844 /* get dump info: endian, class and architecture. 1845 * If the target architecture is not supported, cpu_get_dump_info() will 1846 * return -1. 1847 */ 1848 ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks); 1849 if (ret < 0) { 1850 error_setg(errp, 1851 "dumping guest memory is not supported on this target"); 1852 goto cleanup; 1853 } 1854 1855 if (!s->dump_info.page_size) { 1856 s->dump_info.page_size = qemu_target_page_size(); 1857 } 1858 1859 s->note_size = cpu_get_note_size(s->dump_info.d_class, 1860 s->dump_info.d_machine, nr_cpus); 1861 assert(s->note_size >= 0); 1862 1863 /* 1864 * The goal of this block is to (a) update the previously guessed 1865 * phys_base, (b) copy the guest note out of the guest. 1866 * Failure to do so is not fatal for dumping. 1867 */ 1868 if (vmci) { 1869 uint64_t addr, note_head_size, name_size, desc_size; 1870 uint32_t size; 1871 uint16_t guest_format; 1872 1873 note_head_size = dump_is_64bit(s) ? 1874 sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr); 1875 1876 guest_format = le16_to_cpu(vmci->vmcoreinfo.guest_format); 1877 size = le32_to_cpu(vmci->vmcoreinfo.size); 1878 addr = le64_to_cpu(vmci->vmcoreinfo.paddr); 1879 if (!vmci->has_vmcoreinfo) { 1880 warn_report("guest note is not present"); 1881 } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) { 1882 warn_report("guest note size is invalid: %" PRIu32, size); 1883 } else if (guest_format != FW_CFG_VMCOREINFO_FORMAT_ELF) { 1884 warn_report("guest note format is unsupported: %" PRIu16, guest_format); 1885 } else { 1886 s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */ 1887 cpu_physical_memory_read(addr, s->guest_note, size); 1888 1889 get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size); 1890 s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size, 1891 desc_size); 1892 if (name_size > MAX_GUEST_NOTE_SIZE || 1893 desc_size > MAX_GUEST_NOTE_SIZE || 1894 s->guest_note_size > size) { 1895 warn_report("Invalid guest note header"); 1896 g_free(s->guest_note); 1897 s->guest_note = NULL; 1898 } else { 1899 vmcoreinfo_update_phys_base(s); 1900 s->note_size += s->guest_note_size; 1901 } 1902 } 1903 } 1904 1905 /* get memory mapping */ 1906 if (paging) { 1907 qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, errp); 1908 if (*errp) { 1909 goto cleanup; 1910 } 1911 } else { 1912 qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks); 1913 } 1914 1915 s->nr_cpus = nr_cpus; 1916 1917 get_max_mapnr(s); 1918 1919 uint64_t tmp; 1920 tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), 1921 s->dump_info.page_size); 1922 s->len_dump_bitmap = tmp * s->dump_info.page_size; 1923 1924 /* init for kdump-compressed format */ 1925 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1926 switch (format) { 1927 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB: 1928 s->flag_compress = DUMP_DH_COMPRESSED_ZLIB; 1929 break; 1930 1931 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO: 1932 #ifdef CONFIG_LZO 1933 if (lzo_init() != LZO_E_OK) { 1934 error_setg(errp, "failed to initialize the LZO library"); 1935 goto cleanup; 1936 } 1937 #endif 1938 s->flag_compress = DUMP_DH_COMPRESSED_LZO; 1939 break; 1940 1941 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY: 1942 s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY; 1943 break; 1944 1945 default: 1946 s->flag_compress = 0; 1947 } 1948 1949 return; 1950 } 1951 1952 if (dump_has_filter(s)) { 1953 memory_mapping_filter(&s->list, s->filter_area_begin, s->filter_area_length); 1954 } 1955 1956 /* 1957 * The first section header is always a special one in which most 1958 * fields are 0. The section header string table is also always 1959 * set. 1960 */ 1961 s->shdr_num = 2; 1962 1963 /* 1964 * Adds the number of architecture sections to shdr_num and sets 1965 * elf_section_data_size so we know the offsets and sizes of all 1966 * parts. 1967 */ 1968 if (s->dump_info.arch_sections_add_fn) { 1969 s->dump_info.arch_sections_add_fn(s); 1970 } 1971 1972 /* 1973 * calculate shdr_num so we know the offsets and sizes of all 1974 * parts. 1975 * Calculate phdr_num 1976 * 1977 * The absolute maximum amount of phdrs is UINT32_MAX - 1 as 1978 * sh_info is 32 bit. There's special handling once we go over 1979 * UINT16_MAX - 1 but that is handled in the ehdr and section 1980 * code. 1981 */ 1982 s->phdr_num = 1; /* Reserve PT_NOTE */ 1983 if (s->list.num <= UINT32_MAX - 1) { 1984 s->phdr_num += s->list.num; 1985 } else { 1986 s->phdr_num = UINT32_MAX; 1987 } 1988 1989 /* 1990 * Now that the number of section and program headers is known we 1991 * can calculate the offsets of the headers and data. 1992 */ 1993 if (dump_is_64bit(s)) { 1994 s->shdr_offset = sizeof(Elf64_Ehdr); 1995 s->phdr_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; 1996 s->note_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; 1997 } else { 1998 s->shdr_offset = sizeof(Elf32_Ehdr); 1999 s->phdr_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; 2000 s->note_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; 2001 } 2002 s->memory_offset = s->note_offset + s->note_size; 2003 s->section_offset = s->memory_offset + s->total_size; 2004 2005 return; 2006 2007 cleanup: 2008 dump_cleanup(s); 2009 } 2010 2011 /* this operation might be time consuming. */ 2012 static void dump_process(DumpState *s, Error **errp) 2013 { 2014 ERRP_GUARD(); 2015 DumpQueryResult *result = NULL; 2016 2017 if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { 2018 create_win_dump(s, errp); 2019 } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 2020 create_kdump_vmcore(s, errp); 2021 } else { 2022 create_vmcore(s, errp); 2023 } 2024 2025 /* make sure status is written after written_size updates */ 2026 smp_wmb(); 2027 qatomic_set(&s->status, 2028 (*errp ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED)); 2029 2030 /* send DUMP_COMPLETED message (unconditionally) */ 2031 result = qmp_query_dump(NULL); 2032 /* should never fail */ 2033 assert(result); 2034 qapi_event_send_dump_completed(result, 2035 *errp ? error_get_pretty(*errp) : NULL); 2036 qapi_free_DumpQueryResult(result); 2037 2038 dump_cleanup(s); 2039 } 2040 2041 static void *dump_thread(void *data) 2042 { 2043 DumpState *s = (DumpState *)data; 2044 dump_process(s, NULL); 2045 return NULL; 2046 } 2047 2048 DumpQueryResult *qmp_query_dump(Error **errp) 2049 { 2050 DumpQueryResult *result = g_new(DumpQueryResult, 1); 2051 DumpState *state = &dump_state_global; 2052 result->status = qatomic_read(&state->status); 2053 /* make sure we are reading status and written_size in order */ 2054 smp_rmb(); 2055 result->completed = state->written_size; 2056 result->total = state->total_size; 2057 return result; 2058 } 2059 2060 void qmp_dump_guest_memory(bool paging, const char *protocol, 2061 bool has_detach, bool detach, 2062 bool has_begin, int64_t begin, 2063 bool has_length, int64_t length, 2064 bool has_format, DumpGuestMemoryFormat format, 2065 Error **errp) 2066 { 2067 ERRP_GUARD(); 2068 const char *p; 2069 int fd; 2070 DumpState *s; 2071 bool detach_p = false; 2072 bool kdump_raw = false; 2073 2074 if (runstate_check(RUN_STATE_INMIGRATE)) { 2075 error_setg(errp, "Dump not allowed during incoming migration."); 2076 return; 2077 } 2078 2079 /* if there is a dump in background, we should wait until the dump 2080 * finished */ 2081 if (qemu_system_dump_in_progress()) { 2082 error_setg(errp, "There is a dump in process, please wait."); 2083 return; 2084 } 2085 2086 /* 2087 * externally, we represent kdump-raw-* as separate formats, but internally 2088 * they are handled the same, except for the "raw" flag 2089 */ 2090 if (has_format) { 2091 switch (format) { 2092 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_ZLIB: 2093 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB; 2094 kdump_raw = true; 2095 break; 2096 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_LZO: 2097 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO; 2098 kdump_raw = true; 2099 break; 2100 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_SNAPPY: 2101 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY; 2102 kdump_raw = true; 2103 break; 2104 default: 2105 break; 2106 } 2107 } 2108 2109 /* 2110 * kdump-compressed format need the whole memory dumped, so paging or 2111 * filter is not supported here. 2112 */ 2113 if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) && 2114 (paging || has_begin || has_length)) { 2115 error_setg(errp, "kdump-compressed format doesn't support paging or " 2116 "filter"); 2117 return; 2118 } 2119 if (has_begin && !has_length) { 2120 error_setg(errp, QERR_MISSING_PARAMETER, "length"); 2121 return; 2122 } 2123 if (!has_begin && has_length) { 2124 error_setg(errp, QERR_MISSING_PARAMETER, "begin"); 2125 return; 2126 } 2127 if (has_detach) { 2128 detach_p = detach; 2129 } 2130 2131 /* check whether lzo/snappy is supported */ 2132 #ifndef CONFIG_LZO 2133 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) { 2134 error_setg(errp, "kdump-lzo is not available now"); 2135 return; 2136 } 2137 #endif 2138 2139 #ifndef CONFIG_SNAPPY 2140 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) { 2141 error_setg(errp, "kdump-snappy is not available now"); 2142 return; 2143 } 2144 #endif 2145 2146 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP 2147 && !win_dump_available(errp)) { 2148 return; 2149 } 2150 2151 if (strstart(protocol, "fd:", &p)) { 2152 fd = monitor_get_fd(monitor_cur(), p, errp); 2153 if (fd == -1) { 2154 return; 2155 } 2156 } else if (strstart(protocol, "file:", &p)) { 2157 fd = qemu_create(p, O_WRONLY | O_TRUNC | O_BINARY, S_IRUSR, errp); 2158 if (fd < 0) { 2159 return; 2160 } 2161 } else { 2162 error_setg(errp, 2163 "parameter 'protocol' must start with 'file:' or 'fd:'"); 2164 return; 2165 } 2166 if (kdump_raw && lseek(fd, 0, SEEK_CUR) == (off_t) -1) { 2167 close(fd); 2168 error_setg(errp, "kdump-raw formats require a seekable file"); 2169 return; 2170 } 2171 2172 if (!dump_migration_blocker) { 2173 error_setg(&dump_migration_blocker, 2174 "Live migration disabled: dump-guest-memory in progress"); 2175 } 2176 2177 /* 2178 * Allows even for -only-migratable, but forbid migration during the 2179 * process of dump guest memory. 2180 */ 2181 if (migrate_add_blocker_internal(&dump_migration_blocker, errp)) { 2182 /* Remember to release the fd before passing it over to dump state */ 2183 close(fd); 2184 return; 2185 } 2186 2187 s = &dump_state_global; 2188 dump_state_prepare(s); 2189 2190 dump_init(s, fd, has_format, format, paging, has_begin, 2191 begin, length, kdump_raw, errp); 2192 if (*errp) { 2193 qatomic_set(&s->status, DUMP_STATUS_FAILED); 2194 return; 2195 } 2196 2197 if (detach_p) { 2198 /* detached dump */ 2199 s->detached = true; 2200 qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread, 2201 s, QEMU_THREAD_DETACHED); 2202 } else { 2203 /* sync dump */ 2204 dump_process(s, errp); 2205 } 2206 } 2207 2208 DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp) 2209 { 2210 DumpGuestMemoryCapability *cap = 2211 g_new0(DumpGuestMemoryCapability, 1); 2212 DumpGuestMemoryFormatList **tail = &cap->formats; 2213 2214 /* elf is always available */ 2215 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF); 2216 2217 /* kdump-zlib is always available */ 2218 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB); 2219 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_ZLIB); 2220 2221 /* add new item if kdump-lzo is available */ 2222 #ifdef CONFIG_LZO 2223 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO); 2224 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_LZO); 2225 #endif 2226 2227 /* add new item if kdump-snappy is available */ 2228 #ifdef CONFIG_SNAPPY 2229 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY); 2230 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_SNAPPY); 2231 #endif 2232 2233 if (win_dump_available(NULL)) { 2234 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP); 2235 } 2236 2237 return cap; 2238 } 2239