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 guest_phys_blocks_free(&s->guest_phys_blocks); 100 memory_mapping_list_free(&s->list); 101 close(s->fd); 102 g_free(s->guest_note); 103 g_array_unref(s->string_table_buf); 104 s->guest_note = NULL; 105 if (s->resume) { 106 if (s->detached) { 107 qemu_mutex_lock_iothread(); 108 } 109 vm_start(); 110 if (s->detached) { 111 qemu_mutex_unlock_iothread(); 112 } 113 } 114 migrate_del_blocker(&dump_migration_blocker); 115 116 return 0; 117 } 118 119 static int fd_write_vmcore(const void *buf, size_t size, void *opaque) 120 { 121 DumpState *s = opaque; 122 size_t written_size; 123 124 written_size = qemu_write_full(s->fd, buf, size); 125 if (written_size != size) { 126 return -errno; 127 } 128 129 return 0; 130 } 131 132 static void prepare_elf64_header(DumpState *s, Elf64_Ehdr *elf_header) 133 { 134 /* 135 * phnum in the elf header is 16 bit, if we have more segments we 136 * set phnum to PN_XNUM and write the real number of segments to a 137 * special section. 138 */ 139 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 140 141 memset(elf_header, 0, sizeof(Elf64_Ehdr)); 142 memcpy(elf_header, ELFMAG, SELFMAG); 143 elf_header->e_ident[EI_CLASS] = ELFCLASS64; 144 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 145 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 146 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 147 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 148 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 149 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 150 elf_header->e_phoff = cpu_to_dump64(s, s->phdr_offset); 151 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); 152 elf_header->e_phnum = cpu_to_dump16(s, phnum); 153 elf_header->e_shoff = cpu_to_dump64(s, s->shdr_offset); 154 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); 155 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 156 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 157 } 158 159 static void prepare_elf32_header(DumpState *s, Elf32_Ehdr *elf_header) 160 { 161 /* 162 * phnum in the elf header is 16 bit, if we have more segments we 163 * set phnum to PN_XNUM and write the real number of segments to a 164 * special section. 165 */ 166 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 167 168 memset(elf_header, 0, sizeof(Elf32_Ehdr)); 169 memcpy(elf_header, ELFMAG, SELFMAG); 170 elf_header->e_ident[EI_CLASS] = ELFCLASS32; 171 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 172 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 173 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 174 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 175 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 176 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 177 elf_header->e_phoff = cpu_to_dump32(s, s->phdr_offset); 178 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); 179 elf_header->e_phnum = cpu_to_dump16(s, phnum); 180 elf_header->e_shoff = cpu_to_dump32(s, s->shdr_offset); 181 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); 182 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 183 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 184 } 185 186 static void write_elf_header(DumpState *s, Error **errp) 187 { 188 Elf32_Ehdr elf32_header; 189 Elf64_Ehdr elf64_header; 190 size_t header_size; 191 void *header_ptr; 192 int ret; 193 194 /* The NULL header and the shstrtab are always defined */ 195 assert(s->shdr_num >= 2); 196 if (dump_is_64bit(s)) { 197 prepare_elf64_header(s, &elf64_header); 198 header_size = sizeof(elf64_header); 199 header_ptr = &elf64_header; 200 } else { 201 prepare_elf32_header(s, &elf32_header); 202 header_size = sizeof(elf32_header); 203 header_ptr = &elf32_header; 204 } 205 206 ret = fd_write_vmcore(header_ptr, header_size, s); 207 if (ret < 0) { 208 error_setg_errno(errp, -ret, "dump: failed to write elf header"); 209 } 210 } 211 212 static void write_elf64_load(DumpState *s, MemoryMapping *memory_mapping, 213 int phdr_index, hwaddr offset, 214 hwaddr filesz, Error **errp) 215 { 216 Elf64_Phdr phdr; 217 int ret; 218 219 memset(&phdr, 0, sizeof(Elf64_Phdr)); 220 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 221 phdr.p_offset = cpu_to_dump64(s, offset); 222 phdr.p_paddr = cpu_to_dump64(s, memory_mapping->phys_addr); 223 phdr.p_filesz = cpu_to_dump64(s, filesz); 224 phdr.p_memsz = cpu_to_dump64(s, memory_mapping->length); 225 phdr.p_vaddr = cpu_to_dump64(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 226 227 assert(memory_mapping->length >= filesz); 228 229 ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); 230 if (ret < 0) { 231 error_setg_errno(errp, -ret, 232 "dump: failed to write program header table"); 233 } 234 } 235 236 static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, 237 int phdr_index, hwaddr offset, 238 hwaddr filesz, Error **errp) 239 { 240 Elf32_Phdr phdr; 241 int ret; 242 243 memset(&phdr, 0, sizeof(Elf32_Phdr)); 244 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 245 phdr.p_offset = cpu_to_dump32(s, offset); 246 phdr.p_paddr = cpu_to_dump32(s, memory_mapping->phys_addr); 247 phdr.p_filesz = cpu_to_dump32(s, filesz); 248 phdr.p_memsz = cpu_to_dump32(s, memory_mapping->length); 249 phdr.p_vaddr = 250 cpu_to_dump32(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 251 252 assert(memory_mapping->length >= filesz); 253 254 ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); 255 if (ret < 0) { 256 error_setg_errno(errp, -ret, 257 "dump: failed to write program header table"); 258 } 259 } 260 261 static void prepare_elf64_phdr_note(DumpState *s, Elf64_Phdr *phdr) 262 { 263 memset(phdr, 0, sizeof(*phdr)); 264 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 265 phdr->p_offset = cpu_to_dump64(s, s->note_offset); 266 phdr->p_paddr = 0; 267 phdr->p_filesz = cpu_to_dump64(s, s->note_size); 268 phdr->p_memsz = cpu_to_dump64(s, s->note_size); 269 phdr->p_vaddr = 0; 270 } 271 272 static inline int cpu_index(CPUState *cpu) 273 { 274 return cpu->cpu_index + 1; 275 } 276 277 static void write_guest_note(WriteCoreDumpFunction f, DumpState *s, 278 Error **errp) 279 { 280 int ret; 281 282 if (s->guest_note) { 283 ret = f(s->guest_note, s->guest_note_size, s); 284 if (ret < 0) { 285 error_setg(errp, "dump: failed to write guest note"); 286 } 287 } 288 } 289 290 static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, 291 Error **errp) 292 { 293 CPUState *cpu; 294 int ret; 295 int id; 296 297 CPU_FOREACH(cpu) { 298 id = cpu_index(cpu); 299 ret = cpu_write_elf64_note(f, cpu, id, s); 300 if (ret < 0) { 301 error_setg(errp, "dump: failed to write elf notes"); 302 return; 303 } 304 } 305 306 CPU_FOREACH(cpu) { 307 ret = cpu_write_elf64_qemunote(f, cpu, s); 308 if (ret < 0) { 309 error_setg(errp, "dump: failed to write CPU status"); 310 return; 311 } 312 } 313 314 write_guest_note(f, s, errp); 315 } 316 317 static void prepare_elf32_phdr_note(DumpState *s, Elf32_Phdr *phdr) 318 { 319 memset(phdr, 0, sizeof(*phdr)); 320 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 321 phdr->p_offset = cpu_to_dump32(s, s->note_offset); 322 phdr->p_paddr = 0; 323 phdr->p_filesz = cpu_to_dump32(s, s->note_size); 324 phdr->p_memsz = cpu_to_dump32(s, s->note_size); 325 phdr->p_vaddr = 0; 326 } 327 328 static void write_elf32_notes(WriteCoreDumpFunction f, DumpState *s, 329 Error **errp) 330 { 331 CPUState *cpu; 332 int ret; 333 int id; 334 335 CPU_FOREACH(cpu) { 336 id = cpu_index(cpu); 337 ret = cpu_write_elf32_note(f, cpu, id, s); 338 if (ret < 0) { 339 error_setg(errp, "dump: failed to write elf notes"); 340 return; 341 } 342 } 343 344 CPU_FOREACH(cpu) { 345 ret = cpu_write_elf32_qemunote(f, cpu, s); 346 if (ret < 0) { 347 error_setg(errp, "dump: failed to write CPU status"); 348 return; 349 } 350 } 351 352 write_guest_note(f, s, errp); 353 } 354 355 static void write_elf_phdr_note(DumpState *s, Error **errp) 356 { 357 Elf32_Phdr phdr32; 358 Elf64_Phdr phdr64; 359 void *phdr; 360 size_t size; 361 int ret; 362 363 if (dump_is_64bit(s)) { 364 prepare_elf64_phdr_note(s, &phdr64); 365 size = sizeof(phdr64); 366 phdr = &phdr64; 367 } else { 368 prepare_elf32_phdr_note(s, &phdr32); 369 size = sizeof(phdr32); 370 phdr = &phdr32; 371 } 372 373 ret = fd_write_vmcore(phdr, size, s); 374 if (ret < 0) { 375 error_setg_errno(errp, -ret, 376 "dump: failed to write program header table"); 377 } 378 } 379 380 static void prepare_elf_section_hdr_zero(DumpState *s) 381 { 382 if (dump_is_64bit(s)) { 383 Elf64_Shdr *shdr64 = s->elf_section_hdrs; 384 385 shdr64->sh_info = cpu_to_dump32(s, s->phdr_num); 386 } else { 387 Elf32_Shdr *shdr32 = s->elf_section_hdrs; 388 389 shdr32->sh_info = cpu_to_dump32(s, s->phdr_num); 390 } 391 } 392 393 static void prepare_elf_section_hdr_string(DumpState *s, void *buff) 394 { 395 uint64_t index = s->string_table_buf->len; 396 const char strtab[] = ".shstrtab"; 397 Elf32_Shdr shdr32 = {}; 398 Elf64_Shdr shdr64 = {}; 399 int shdr_size; 400 void *shdr; 401 402 g_array_append_vals(s->string_table_buf, strtab, sizeof(strtab)); 403 if (dump_is_64bit(s)) { 404 shdr_size = sizeof(Elf64_Shdr); 405 shdr64.sh_type = SHT_STRTAB; 406 shdr64.sh_offset = s->section_offset + s->elf_section_data_size; 407 shdr64.sh_name = index; 408 shdr64.sh_size = s->string_table_buf->len; 409 shdr = &shdr64; 410 } else { 411 shdr_size = sizeof(Elf32_Shdr); 412 shdr32.sh_type = SHT_STRTAB; 413 shdr32.sh_offset = s->section_offset + s->elf_section_data_size; 414 shdr32.sh_name = index; 415 shdr32.sh_size = s->string_table_buf->len; 416 shdr = &shdr32; 417 } 418 memcpy(buff, shdr, shdr_size); 419 } 420 421 static bool prepare_elf_section_hdrs(DumpState *s, Error **errp) 422 { 423 size_t len, sizeof_shdr; 424 void *buff_hdr; 425 426 /* 427 * Section ordering: 428 * - HDR zero 429 * - Arch section hdrs 430 * - String table hdr 431 */ 432 sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); 433 len = sizeof_shdr * s->shdr_num; 434 s->elf_section_hdrs = g_malloc0(len); 435 buff_hdr = s->elf_section_hdrs; 436 437 /* 438 * The first section header is ALWAYS a special initial section 439 * header. 440 * 441 * The header should be 0 with one exception being that if 442 * phdr_num is PN_XNUM then the sh_info field contains the real 443 * number of segment entries. 444 * 445 * As we zero allocate the buffer we will only need to modify 446 * sh_info for the PN_XNUM case. 447 */ 448 if (s->phdr_num >= PN_XNUM) { 449 prepare_elf_section_hdr_zero(s); 450 } 451 buff_hdr += sizeof_shdr; 452 453 /* Add architecture defined section headers */ 454 if (s->dump_info.arch_sections_write_hdr_fn 455 && s->shdr_num > 2) { 456 buff_hdr += s->dump_info.arch_sections_write_hdr_fn(s, buff_hdr); 457 458 if (s->shdr_num >= SHN_LORESERVE) { 459 error_setg_errno(errp, EINVAL, 460 "dump: too many architecture defined sections"); 461 return false; 462 } 463 } 464 465 /* 466 * String table is the last section since strings are added via 467 * arch_sections_write_hdr(). 468 */ 469 prepare_elf_section_hdr_string(s, buff_hdr); 470 return true; 471 } 472 473 static void write_elf_section_headers(DumpState *s, Error **errp) 474 { 475 size_t sizeof_shdr = dump_is_64bit(s) ? sizeof(Elf64_Shdr) : sizeof(Elf32_Shdr); 476 int ret; 477 478 if (!prepare_elf_section_hdrs(s, errp)) { 479 return; 480 } 481 482 ret = fd_write_vmcore(s->elf_section_hdrs, s->shdr_num * sizeof_shdr, s); 483 if (ret < 0) { 484 error_setg_errno(errp, -ret, "dump: failed to write section headers"); 485 } 486 487 g_free(s->elf_section_hdrs); 488 } 489 490 static void write_elf_sections(DumpState *s, Error **errp) 491 { 492 int ret; 493 494 if (s->elf_section_data_size) { 495 /* Write architecture section data */ 496 ret = fd_write_vmcore(s->elf_section_data, 497 s->elf_section_data_size, s); 498 if (ret < 0) { 499 error_setg_errno(errp, -ret, 500 "dump: failed to write architecture section data"); 501 return; 502 } 503 } 504 505 /* Write string table */ 506 ret = fd_write_vmcore(s->string_table_buf->data, 507 s->string_table_buf->len, s); 508 if (ret < 0) { 509 error_setg_errno(errp, -ret, "dump: failed to write string table data"); 510 } 511 } 512 513 static void write_data(DumpState *s, void *buf, int length, Error **errp) 514 { 515 int ret; 516 517 ret = fd_write_vmcore(buf, length, s); 518 if (ret < 0) { 519 error_setg_errno(errp, -ret, "dump: failed to save memory"); 520 } else { 521 s->written_size += length; 522 } 523 } 524 525 /* write the memory to vmcore. 1 page per I/O. */ 526 static void write_memory(DumpState *s, GuestPhysBlock *block, ram_addr_t start, 527 int64_t size, Error **errp) 528 { 529 ERRP_GUARD(); 530 int64_t i; 531 532 for (i = 0; i < size / s->dump_info.page_size; i++) { 533 write_data(s, block->host_addr + start + i * s->dump_info.page_size, 534 s->dump_info.page_size, errp); 535 if (*errp) { 536 return; 537 } 538 } 539 540 if ((size % s->dump_info.page_size) != 0) { 541 write_data(s, block->host_addr + start + i * s->dump_info.page_size, 542 size % s->dump_info.page_size, errp); 543 if (*errp) { 544 return; 545 } 546 } 547 } 548 549 /* get the memory's offset and size in the vmcore */ 550 static void get_offset_range(hwaddr phys_addr, 551 ram_addr_t mapping_length, 552 DumpState *s, 553 hwaddr *p_offset, 554 hwaddr *p_filesz) 555 { 556 GuestPhysBlock *block; 557 hwaddr offset = s->memory_offset; 558 int64_t size_in_block, start; 559 560 /* When the memory is not stored into vmcore, offset will be -1 */ 561 *p_offset = -1; 562 *p_filesz = 0; 563 564 if (dump_has_filter(s)) { 565 if (phys_addr < s->filter_area_begin || 566 phys_addr >= s->filter_area_begin + s->filter_area_length) { 567 return; 568 } 569 } 570 571 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 572 if (dump_has_filter(s)) { 573 if (block->target_start >= s->filter_area_begin + s->filter_area_length || 574 block->target_end <= s->filter_area_begin) { 575 /* This block is out of the range */ 576 continue; 577 } 578 579 if (s->filter_area_begin <= block->target_start) { 580 start = block->target_start; 581 } else { 582 start = s->filter_area_begin; 583 } 584 585 size_in_block = block->target_end - start; 586 if (s->filter_area_begin + s->filter_area_length < block->target_end) { 587 size_in_block -= block->target_end - (s->filter_area_begin + s->filter_area_length); 588 } 589 } else { 590 start = block->target_start; 591 size_in_block = block->target_end - block->target_start; 592 } 593 594 if (phys_addr >= start && phys_addr < start + size_in_block) { 595 *p_offset = phys_addr - start + offset; 596 597 /* The offset range mapped from the vmcore file must not spill over 598 * the GuestPhysBlock, clamp it. The rest of the mapping will be 599 * zero-filled in memory at load time; see 600 * <http://refspecs.linuxbase.org/elf/gabi4+/ch5.pheader.html>. 601 */ 602 *p_filesz = phys_addr + mapping_length <= start + size_in_block ? 603 mapping_length : 604 size_in_block - (phys_addr - start); 605 return; 606 } 607 608 offset += size_in_block; 609 } 610 } 611 612 static void write_elf_phdr_loads(DumpState *s, Error **errp) 613 { 614 ERRP_GUARD(); 615 hwaddr offset, filesz; 616 MemoryMapping *memory_mapping; 617 uint32_t phdr_index = 1; 618 619 QTAILQ_FOREACH(memory_mapping, &s->list.head, next) { 620 get_offset_range(memory_mapping->phys_addr, 621 memory_mapping->length, 622 s, &offset, &filesz); 623 if (dump_is_64bit(s)) { 624 write_elf64_load(s, memory_mapping, phdr_index++, offset, 625 filesz, errp); 626 } else { 627 write_elf32_load(s, memory_mapping, phdr_index++, offset, 628 filesz, errp); 629 } 630 631 if (*errp) { 632 return; 633 } 634 635 if (phdr_index >= s->phdr_num) { 636 break; 637 } 638 } 639 } 640 641 static void write_elf_notes(DumpState *s, Error **errp) 642 { 643 if (dump_is_64bit(s)) { 644 write_elf64_notes(fd_write_vmcore, s, errp); 645 } else { 646 write_elf32_notes(fd_write_vmcore, s, errp); 647 } 648 } 649 650 /* write elf header, PT_NOTE and elf note to vmcore. */ 651 static void dump_begin(DumpState *s, Error **errp) 652 { 653 ERRP_GUARD(); 654 655 /* 656 * the vmcore's format is: 657 * -------------- 658 * | elf header | 659 * -------------- 660 * | sctn_hdr | 661 * -------------- 662 * | PT_NOTE | 663 * -------------- 664 * | PT_LOAD | 665 * -------------- 666 * | ...... | 667 * -------------- 668 * | PT_LOAD | 669 * -------------- 670 * | elf note | 671 * -------------- 672 * | memory | 673 * -------------- 674 * 675 * we only know where the memory is saved after we write elf note into 676 * vmcore. 677 */ 678 679 /* write elf header to vmcore */ 680 write_elf_header(s, errp); 681 if (*errp) { 682 return; 683 } 684 685 /* write section headers to vmcore */ 686 write_elf_section_headers(s, errp); 687 if (*errp) { 688 return; 689 } 690 691 /* write PT_NOTE to vmcore */ 692 write_elf_phdr_note(s, errp); 693 if (*errp) { 694 return; 695 } 696 697 /* write all PT_LOADs to vmcore */ 698 write_elf_phdr_loads(s, errp); 699 if (*errp) { 700 return; 701 } 702 703 /* write notes to vmcore */ 704 write_elf_notes(s, errp); 705 } 706 707 int64_t dump_filtered_memblock_size(GuestPhysBlock *block, 708 int64_t filter_area_start, 709 int64_t filter_area_length) 710 { 711 int64_t size, left, right; 712 713 /* No filter, return full size */ 714 if (!filter_area_length) { 715 return block->target_end - block->target_start; 716 } 717 718 /* calculate the overlapped region. */ 719 left = MAX(filter_area_start, block->target_start); 720 right = MIN(filter_area_start + filter_area_length, block->target_end); 721 size = right - left; 722 size = size > 0 ? size : 0; 723 724 return size; 725 } 726 727 int64_t dump_filtered_memblock_start(GuestPhysBlock *block, 728 int64_t filter_area_start, 729 int64_t filter_area_length) 730 { 731 if (filter_area_length) { 732 /* return -1 if the block is not within filter area */ 733 if (block->target_start >= filter_area_start + filter_area_length || 734 block->target_end <= filter_area_start) { 735 return -1; 736 } 737 738 if (filter_area_start > block->target_start) { 739 return filter_area_start - block->target_start; 740 } 741 } 742 743 return 0; 744 } 745 746 /* write all memory to vmcore */ 747 static void dump_iterate(DumpState *s, Error **errp) 748 { 749 ERRP_GUARD(); 750 GuestPhysBlock *block; 751 int64_t memblock_size, memblock_start; 752 753 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 754 memblock_start = dump_filtered_memblock_start(block, s->filter_area_begin, s->filter_area_length); 755 if (memblock_start == -1) { 756 continue; 757 } 758 759 memblock_size = dump_filtered_memblock_size(block, s->filter_area_begin, s->filter_area_length); 760 761 /* Write the memory to file */ 762 write_memory(s, block, memblock_start, memblock_size, errp); 763 if (*errp) { 764 return; 765 } 766 } 767 } 768 769 static void dump_end(DumpState *s, Error **errp) 770 { 771 int rc; 772 773 if (s->elf_section_data_size) { 774 s->elf_section_data = g_malloc0(s->elf_section_data_size); 775 } 776 777 /* Adds the architecture defined section data to s->elf_section_data */ 778 if (s->dump_info.arch_sections_write_fn && 779 s->elf_section_data_size) { 780 rc = s->dump_info.arch_sections_write_fn(s, s->elf_section_data); 781 if (rc) { 782 error_setg_errno(errp, rc, 783 "dump: failed to get arch section data"); 784 g_free(s->elf_section_data); 785 return; 786 } 787 } 788 789 /* write sections to vmcore */ 790 write_elf_sections(s, errp); 791 } 792 793 static void create_vmcore(DumpState *s, Error **errp) 794 { 795 ERRP_GUARD(); 796 797 dump_begin(s, errp); 798 if (*errp) { 799 return; 800 } 801 802 /* Iterate over memory and dump it to file */ 803 dump_iterate(s, errp); 804 if (*errp) { 805 return; 806 } 807 808 /* Write the section data */ 809 dump_end(s, errp); 810 } 811 812 static int write_start_flat_header(DumpState *s) 813 { 814 MakedumpfileHeader *mh; 815 int ret = 0; 816 817 if (s->kdump_raw) { 818 return 0; 819 } 820 821 QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER); 822 mh = g_malloc0(MAX_SIZE_MDF_HEADER); 823 824 memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE, 825 MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE)); 826 827 mh->type = cpu_to_be64(TYPE_FLAT_HEADER); 828 mh->version = cpu_to_be64(VERSION_FLAT_HEADER); 829 830 size_t written_size; 831 written_size = qemu_write_full(s->fd, mh, MAX_SIZE_MDF_HEADER); 832 if (written_size != MAX_SIZE_MDF_HEADER) { 833 ret = -1; 834 } 835 836 g_free(mh); 837 return ret; 838 } 839 840 static int write_end_flat_header(DumpState *s) 841 { 842 MakedumpfileDataHeader mdh; 843 844 if (s->kdump_raw) { 845 return 0; 846 } 847 848 mdh.offset = END_FLAG_FLAT_HEADER; 849 mdh.buf_size = END_FLAG_FLAT_HEADER; 850 851 size_t written_size; 852 written_size = qemu_write_full(s->fd, &mdh, sizeof(mdh)); 853 if (written_size != sizeof(mdh)) { 854 return -1; 855 } 856 857 return 0; 858 } 859 860 static int write_buffer(DumpState *s, off_t offset, const void *buf, size_t size) 861 { 862 size_t written_size; 863 MakedumpfileDataHeader mdh; 864 off_t seek_loc; 865 866 if (s->kdump_raw) { 867 seek_loc = lseek(s->fd, offset, SEEK_SET); 868 if (seek_loc == (off_t) -1) { 869 return -1; 870 } 871 } else { 872 mdh.offset = cpu_to_be64(offset); 873 mdh.buf_size = cpu_to_be64(size); 874 875 written_size = qemu_write_full(s->fd, &mdh, sizeof(mdh)); 876 if (written_size != sizeof(mdh)) { 877 return -1; 878 } 879 } 880 881 written_size = qemu_write_full(s->fd, buf, size); 882 if (written_size != size) { 883 return -1; 884 } 885 886 return 0; 887 } 888 889 static int buf_write_note(const void *buf, size_t size, void *opaque) 890 { 891 DumpState *s = opaque; 892 893 /* note_buf is not enough */ 894 if (s->note_buf_offset + size > s->note_size) { 895 return -1; 896 } 897 898 memcpy(s->note_buf + s->note_buf_offset, buf, size); 899 900 s->note_buf_offset += size; 901 902 return 0; 903 } 904 905 /* 906 * This function retrieves various sizes from an elf header. 907 * 908 * @note has to be a valid ELF note. The return sizes are unmodified 909 * (not padded or rounded up to be multiple of 4). 910 */ 911 static void get_note_sizes(DumpState *s, const void *note, 912 uint64_t *note_head_size, 913 uint64_t *name_size, 914 uint64_t *desc_size) 915 { 916 uint64_t note_head_sz; 917 uint64_t name_sz; 918 uint64_t desc_sz; 919 920 if (dump_is_64bit(s)) { 921 const Elf64_Nhdr *hdr = note; 922 note_head_sz = sizeof(Elf64_Nhdr); 923 name_sz = cpu_to_dump64(s, hdr->n_namesz); 924 desc_sz = cpu_to_dump64(s, hdr->n_descsz); 925 } else { 926 const Elf32_Nhdr *hdr = note; 927 note_head_sz = sizeof(Elf32_Nhdr); 928 name_sz = cpu_to_dump32(s, hdr->n_namesz); 929 desc_sz = cpu_to_dump32(s, hdr->n_descsz); 930 } 931 932 if (note_head_size) { 933 *note_head_size = note_head_sz; 934 } 935 if (name_size) { 936 *name_size = name_sz; 937 } 938 if (desc_size) { 939 *desc_size = desc_sz; 940 } 941 } 942 943 static bool note_name_equal(DumpState *s, 944 const uint8_t *note, const char *name) 945 { 946 int len = strlen(name) + 1; 947 uint64_t head_size, name_size; 948 949 get_note_sizes(s, note, &head_size, &name_size, NULL); 950 head_size = ROUND_UP(head_size, 4); 951 952 return name_size == len && memcmp(note + head_size, name, len) == 0; 953 } 954 955 /* write common header, sub header and elf note to vmcore */ 956 static void create_header32(DumpState *s, Error **errp) 957 { 958 ERRP_GUARD(); 959 DiskDumpHeader32 *dh = NULL; 960 KdumpSubHeader32 *kh = NULL; 961 size_t size; 962 uint32_t block_size; 963 uint32_t sub_hdr_size; 964 uint32_t bitmap_blocks; 965 uint32_t status = 0; 966 uint64_t offset_note; 967 968 /* write common header, the version of kdump-compressed format is 6th */ 969 size = sizeof(DiskDumpHeader32); 970 dh = g_malloc0(size); 971 972 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 973 dh->header_version = cpu_to_dump32(s, 6); 974 block_size = s->dump_info.page_size; 975 dh->block_size = cpu_to_dump32(s, block_size); 976 sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size; 977 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 978 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 979 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 980 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 981 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 982 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 983 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 984 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 985 986 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 987 status |= DUMP_DH_COMPRESSED_ZLIB; 988 } 989 #ifdef CONFIG_LZO 990 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 991 status |= DUMP_DH_COMPRESSED_LZO; 992 } 993 #endif 994 #ifdef CONFIG_SNAPPY 995 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 996 status |= DUMP_DH_COMPRESSED_SNAPPY; 997 } 998 #endif 999 dh->status = cpu_to_dump32(s, status); 1000 1001 if (write_buffer(s, 0, dh, size) < 0) { 1002 error_setg(errp, "dump: failed to write disk dump header"); 1003 goto out; 1004 } 1005 1006 /* write sub header */ 1007 size = sizeof(KdumpSubHeader32); 1008 kh = g_malloc0(size); 1009 1010 /* 64bit max_mapnr_64 */ 1011 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1012 kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base); 1013 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1014 1015 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1016 if (s->guest_note && 1017 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1018 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1019 1020 get_note_sizes(s, s->guest_note, 1021 &hsize, &name_size, &size_vmcoreinfo_desc); 1022 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1023 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1024 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1025 kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc); 1026 } 1027 1028 kh->offset_note = cpu_to_dump64(s, offset_note); 1029 kh->note_size = cpu_to_dump32(s, s->note_size); 1030 1031 if (write_buffer(s, DISKDUMP_HEADER_BLOCKS * 1032 block_size, kh, size) < 0) { 1033 error_setg(errp, "dump: failed to write kdump sub header"); 1034 goto out; 1035 } 1036 1037 /* write note */ 1038 s->note_buf = g_malloc0(s->note_size); 1039 s->note_buf_offset = 0; 1040 1041 /* use s->note_buf to store notes temporarily */ 1042 write_elf32_notes(buf_write_note, s, errp); 1043 if (*errp) { 1044 goto out; 1045 } 1046 if (write_buffer(s, offset_note, s->note_buf, 1047 s->note_size) < 0) { 1048 error_setg(errp, "dump: failed to write notes"); 1049 goto out; 1050 } 1051 1052 /* get offset of dump_bitmap */ 1053 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1054 block_size; 1055 1056 /* get offset of page */ 1057 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1058 block_size; 1059 1060 out: 1061 g_free(dh); 1062 g_free(kh); 1063 g_free(s->note_buf); 1064 } 1065 1066 /* write common header, sub header and elf note to vmcore */ 1067 static void create_header64(DumpState *s, Error **errp) 1068 { 1069 ERRP_GUARD(); 1070 DiskDumpHeader64 *dh = NULL; 1071 KdumpSubHeader64 *kh = NULL; 1072 size_t size; 1073 uint32_t block_size; 1074 uint32_t sub_hdr_size; 1075 uint32_t bitmap_blocks; 1076 uint32_t status = 0; 1077 uint64_t offset_note; 1078 1079 /* write common header, the version of kdump-compressed format is 6th */ 1080 size = sizeof(DiskDumpHeader64); 1081 dh = g_malloc0(size); 1082 1083 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 1084 dh->header_version = cpu_to_dump32(s, 6); 1085 block_size = s->dump_info.page_size; 1086 dh->block_size = cpu_to_dump32(s, block_size); 1087 sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size; 1088 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 1089 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 1090 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 1091 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 1092 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 1093 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 1094 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 1095 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 1096 1097 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 1098 status |= DUMP_DH_COMPRESSED_ZLIB; 1099 } 1100 #ifdef CONFIG_LZO 1101 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 1102 status |= DUMP_DH_COMPRESSED_LZO; 1103 } 1104 #endif 1105 #ifdef CONFIG_SNAPPY 1106 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 1107 status |= DUMP_DH_COMPRESSED_SNAPPY; 1108 } 1109 #endif 1110 dh->status = cpu_to_dump32(s, status); 1111 1112 if (write_buffer(s, 0, dh, size) < 0) { 1113 error_setg(errp, "dump: failed to write disk dump header"); 1114 goto out; 1115 } 1116 1117 /* write sub header */ 1118 size = sizeof(KdumpSubHeader64); 1119 kh = g_malloc0(size); 1120 1121 /* 64bit max_mapnr_64 */ 1122 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1123 kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base); 1124 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1125 1126 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1127 if (s->guest_note && 1128 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1129 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1130 1131 get_note_sizes(s, s->guest_note, 1132 &hsize, &name_size, &size_vmcoreinfo_desc); 1133 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1134 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1135 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1136 kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc); 1137 } 1138 1139 kh->offset_note = cpu_to_dump64(s, offset_note); 1140 kh->note_size = cpu_to_dump64(s, s->note_size); 1141 1142 if (write_buffer(s, DISKDUMP_HEADER_BLOCKS * 1143 block_size, kh, size) < 0) { 1144 error_setg(errp, "dump: failed to write kdump sub header"); 1145 goto out; 1146 } 1147 1148 /* write note */ 1149 s->note_buf = g_malloc0(s->note_size); 1150 s->note_buf_offset = 0; 1151 1152 /* use s->note_buf to store notes temporarily */ 1153 write_elf64_notes(buf_write_note, s, errp); 1154 if (*errp) { 1155 goto out; 1156 } 1157 1158 if (write_buffer(s, offset_note, s->note_buf, 1159 s->note_size) < 0) { 1160 error_setg(errp, "dump: failed to write notes"); 1161 goto out; 1162 } 1163 1164 /* get offset of dump_bitmap */ 1165 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1166 block_size; 1167 1168 /* get offset of page */ 1169 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1170 block_size; 1171 1172 out: 1173 g_free(dh); 1174 g_free(kh); 1175 g_free(s->note_buf); 1176 } 1177 1178 static void write_dump_header(DumpState *s, Error **errp) 1179 { 1180 if (dump_is_64bit(s)) { 1181 create_header64(s, errp); 1182 } else { 1183 create_header32(s, errp); 1184 } 1185 } 1186 1187 static size_t dump_bitmap_get_bufsize(DumpState *s) 1188 { 1189 return s->dump_info.page_size; 1190 } 1191 1192 /* 1193 * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be 1194 * rewritten, so if need to set the first bit, set last_pfn and pfn to 0. 1195 * set_dump_bitmap will always leave the recently set bit un-sync. And setting 1196 * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into 1197 * vmcore, ie. synchronizing un-sync bit into vmcore. 1198 */ 1199 static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value, 1200 uint8_t *buf, DumpState *s) 1201 { 1202 off_t old_offset, new_offset; 1203 off_t offset_bitmap1, offset_bitmap2; 1204 uint32_t byte, bit; 1205 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1206 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1207 1208 /* should not set the previous place */ 1209 assert(last_pfn <= pfn); 1210 1211 /* 1212 * if the bit needed to be set is not cached in buf, flush the data in buf 1213 * to vmcore firstly. 1214 * making new_offset be bigger than old_offset can also sync remained data 1215 * into vmcore. 1216 */ 1217 old_offset = bitmap_bufsize * (last_pfn / bits_per_buf); 1218 new_offset = bitmap_bufsize * (pfn / bits_per_buf); 1219 1220 while (old_offset < new_offset) { 1221 /* calculate the offset and write dump_bitmap */ 1222 offset_bitmap1 = s->offset_dump_bitmap + old_offset; 1223 if (write_buffer(s, offset_bitmap1, buf, 1224 bitmap_bufsize) < 0) { 1225 return -1; 1226 } 1227 1228 /* dump level 1 is chosen, so 1st and 2nd bitmap are same */ 1229 offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap + 1230 old_offset; 1231 if (write_buffer(s, offset_bitmap2, buf, 1232 bitmap_bufsize) < 0) { 1233 return -1; 1234 } 1235 1236 memset(buf, 0, bitmap_bufsize); 1237 old_offset += bitmap_bufsize; 1238 } 1239 1240 /* get the exact place of the bit in the buf, and set it */ 1241 byte = (pfn % bits_per_buf) / CHAR_BIT; 1242 bit = (pfn % bits_per_buf) % CHAR_BIT; 1243 if (value) { 1244 buf[byte] |= 1u << bit; 1245 } else { 1246 buf[byte] &= ~(1u << bit); 1247 } 1248 1249 return 0; 1250 } 1251 1252 static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr) 1253 { 1254 int target_page_shift = ctz32(s->dump_info.page_size); 1255 1256 return (addr >> target_page_shift) - ARCH_PFN_OFFSET; 1257 } 1258 1259 static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn) 1260 { 1261 int target_page_shift = ctz32(s->dump_info.page_size); 1262 1263 return (pfn + ARCH_PFN_OFFSET) << target_page_shift; 1264 } 1265 1266 /* 1267 * Return the page frame number and the page content in *bufptr. bufptr can be 1268 * NULL. If not NULL, *bufptr must contains a target page size of pre-allocated 1269 * memory. This is not necessarily the memory returned. 1270 */ 1271 static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr, 1272 uint8_t **bufptr, DumpState *s) 1273 { 1274 GuestPhysBlock *block = *blockptr; 1275 uint32_t page_size = s->dump_info.page_size; 1276 uint8_t *buf = NULL, *hbuf; 1277 hwaddr addr; 1278 1279 /* block == NULL means the start of the iteration */ 1280 if (!block) { 1281 block = QTAILQ_FIRST(&s->guest_phys_blocks.head); 1282 *blockptr = block; 1283 addr = block->target_start; 1284 *pfnptr = dump_paddr_to_pfn(s, addr); 1285 } else { 1286 *pfnptr += 1; 1287 addr = dump_pfn_to_paddr(s, *pfnptr); 1288 } 1289 assert(block != NULL); 1290 1291 while (1) { 1292 if (addr >= block->target_start && addr < block->target_end) { 1293 size_t n = MIN(block->target_end - addr, page_size - addr % page_size); 1294 hbuf = block->host_addr + (addr - block->target_start); 1295 if (!buf) { 1296 if (n == page_size) { 1297 /* this is a whole target page, go for it */ 1298 assert(addr % page_size == 0); 1299 buf = hbuf; 1300 break; 1301 } else if (bufptr) { 1302 assert(*bufptr); 1303 buf = *bufptr; 1304 memset(buf, 0, page_size); 1305 } else { 1306 return true; 1307 } 1308 } 1309 1310 memcpy(buf + addr % page_size, hbuf, n); 1311 addr += n; 1312 if (addr % page_size == 0 || addr >= block->target_end) { 1313 /* we filled up the page or the current block is finished */ 1314 break; 1315 } 1316 } else { 1317 /* the next page is in the next block */ 1318 *blockptr = block = QTAILQ_NEXT(block, next); 1319 if (!block) { 1320 break; 1321 } 1322 1323 addr = block->target_start; 1324 /* are we still in the same page? */ 1325 if (dump_paddr_to_pfn(s, addr) != *pfnptr) { 1326 if (buf) { 1327 /* no, but we already filled something earlier, return it */ 1328 break; 1329 } else { 1330 /* else continue from there */ 1331 *pfnptr = dump_paddr_to_pfn(s, addr); 1332 } 1333 } 1334 } 1335 } 1336 1337 if (bufptr) { 1338 *bufptr = buf; 1339 } 1340 1341 return buf != NULL; 1342 } 1343 1344 static void write_dump_bitmap(DumpState *s, Error **errp) 1345 { 1346 int ret = 0; 1347 uint64_t last_pfn, pfn; 1348 void *dump_bitmap_buf; 1349 size_t num_dumpable; 1350 GuestPhysBlock *block_iter = NULL; 1351 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1352 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1353 1354 /* dump_bitmap_buf is used to store dump_bitmap temporarily */ 1355 dump_bitmap_buf = g_malloc0(bitmap_bufsize); 1356 1357 num_dumpable = 0; 1358 last_pfn = 0; 1359 1360 /* 1361 * exam memory page by page, and set the bit in dump_bitmap corresponded 1362 * to the existing page. 1363 */ 1364 while (get_next_page(&block_iter, &pfn, NULL, s)) { 1365 ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s); 1366 if (ret < 0) { 1367 error_setg(errp, "dump: failed to set dump_bitmap"); 1368 goto out; 1369 } 1370 1371 last_pfn = pfn; 1372 num_dumpable++; 1373 } 1374 1375 /* 1376 * set_dump_bitmap will always leave the recently set bit un-sync. Here we 1377 * set the remaining bits from last_pfn to the end of the bitmap buffer to 1378 * 0. With those set, the un-sync bit will be synchronized into the vmcore. 1379 */ 1380 if (num_dumpable > 0) { 1381 ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false, 1382 dump_bitmap_buf, s); 1383 if (ret < 0) { 1384 error_setg(errp, "dump: failed to sync dump_bitmap"); 1385 goto out; 1386 } 1387 } 1388 1389 /* number of dumpable pages that will be dumped later */ 1390 s->num_dumpable = num_dumpable; 1391 1392 out: 1393 g_free(dump_bitmap_buf); 1394 } 1395 1396 static void prepare_data_cache(DataCache *data_cache, DumpState *s, 1397 off_t offset) 1398 { 1399 data_cache->state = s; 1400 data_cache->data_size = 0; 1401 data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s); 1402 data_cache->buf = g_malloc0(data_cache->buf_size); 1403 data_cache->offset = offset; 1404 } 1405 1406 static int write_cache(DataCache *dc, const void *buf, size_t size, 1407 bool flag_sync) 1408 { 1409 /* 1410 * dc->buf_size should not be less than size, otherwise dc will never be 1411 * enough 1412 */ 1413 assert(size <= dc->buf_size); 1414 1415 /* 1416 * if flag_sync is set, synchronize data in dc->buf into vmcore. 1417 * otherwise check if the space is enough for caching data in buf, if not, 1418 * write the data in dc->buf to dc->state->fd and reset dc->buf 1419 */ 1420 if ((!flag_sync && dc->data_size + size > dc->buf_size) || 1421 (flag_sync && dc->data_size > 0)) { 1422 if (write_buffer(dc->state, dc->offset, dc->buf, dc->data_size) < 0) { 1423 return -1; 1424 } 1425 1426 dc->offset += dc->data_size; 1427 dc->data_size = 0; 1428 } 1429 1430 if (!flag_sync) { 1431 memcpy(dc->buf + dc->data_size, buf, size); 1432 dc->data_size += size; 1433 } 1434 1435 return 0; 1436 } 1437 1438 static void free_data_cache(DataCache *data_cache) 1439 { 1440 g_free(data_cache->buf); 1441 } 1442 1443 static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress) 1444 { 1445 switch (flag_compress) { 1446 case DUMP_DH_COMPRESSED_ZLIB: 1447 return compressBound(page_size); 1448 1449 case DUMP_DH_COMPRESSED_LZO: 1450 /* 1451 * LZO will expand incompressible data by a little amount. Please check 1452 * the following URL to see the expansion calculation: 1453 * http://www.oberhumer.com/opensource/lzo/lzofaq.php 1454 */ 1455 return page_size + page_size / 16 + 64 + 3; 1456 1457 #ifdef CONFIG_SNAPPY 1458 case DUMP_DH_COMPRESSED_SNAPPY: 1459 return snappy_max_compressed_length(page_size); 1460 #endif 1461 } 1462 return 0; 1463 } 1464 1465 static void write_dump_pages(DumpState *s, Error **errp) 1466 { 1467 int ret = 0; 1468 DataCache page_desc, page_data; 1469 size_t len_buf_out, size_out; 1470 #ifdef CONFIG_LZO 1471 lzo_bytep wrkmem = NULL; 1472 #endif 1473 uint8_t *buf_out = NULL; 1474 off_t offset_desc, offset_data; 1475 PageDescriptor pd, pd_zero; 1476 uint8_t *buf; 1477 GuestPhysBlock *block_iter = NULL; 1478 uint64_t pfn_iter; 1479 g_autofree uint8_t *page = NULL; 1480 1481 /* get offset of page_desc and page_data in dump file */ 1482 offset_desc = s->offset_page; 1483 offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable; 1484 1485 prepare_data_cache(&page_desc, s, offset_desc); 1486 prepare_data_cache(&page_data, s, offset_data); 1487 1488 /* prepare buffer to store compressed data */ 1489 len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress); 1490 assert(len_buf_out != 0); 1491 1492 #ifdef CONFIG_LZO 1493 wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS); 1494 #endif 1495 1496 buf_out = g_malloc(len_buf_out); 1497 1498 /* 1499 * init zero page's page_desc and page_data, because every zero page 1500 * uses the same page_data 1501 */ 1502 pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size); 1503 pd_zero.flags = cpu_to_dump32(s, 0); 1504 pd_zero.offset = cpu_to_dump64(s, offset_data); 1505 pd_zero.page_flags = cpu_to_dump64(s, 0); 1506 buf = g_malloc0(s->dump_info.page_size); 1507 ret = write_cache(&page_data, buf, s->dump_info.page_size, false); 1508 g_free(buf); 1509 if (ret < 0) { 1510 error_setg(errp, "dump: failed to write page data (zero page)"); 1511 goto out; 1512 } 1513 1514 offset_data += s->dump_info.page_size; 1515 page = g_malloc(s->dump_info.page_size); 1516 1517 /* 1518 * dump memory to vmcore page by page. zero page will all be resided in the 1519 * first page of page section 1520 */ 1521 for (buf = page; get_next_page(&block_iter, &pfn_iter, &buf, s); buf = page) { 1522 /* check zero page */ 1523 if (buffer_is_zero(buf, s->dump_info.page_size)) { 1524 ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor), 1525 false); 1526 if (ret < 0) { 1527 error_setg(errp, "dump: failed to write page desc"); 1528 goto out; 1529 } 1530 } else { 1531 /* 1532 * not zero page, then: 1533 * 1. compress the page 1534 * 2. write the compressed page into the cache of page_data 1535 * 3. get page desc of the compressed page and write it into the 1536 * cache of page_desc 1537 * 1538 * only one compression format will be used here, for 1539 * s->flag_compress is set. But when compression fails to work, 1540 * we fall back to save in plaintext. 1541 */ 1542 size_out = len_buf_out; 1543 if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) && 1544 (compress2(buf_out, (uLongf *)&size_out, buf, 1545 s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) && 1546 (size_out < s->dump_info.page_size)) { 1547 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB); 1548 pd.size = cpu_to_dump32(s, size_out); 1549 1550 ret = write_cache(&page_data, buf_out, size_out, false); 1551 if (ret < 0) { 1552 error_setg(errp, "dump: failed to write page data"); 1553 goto out; 1554 } 1555 #ifdef CONFIG_LZO 1556 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) && 1557 (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out, 1558 (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) && 1559 (size_out < s->dump_info.page_size)) { 1560 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO); 1561 pd.size = cpu_to_dump32(s, size_out); 1562 1563 ret = write_cache(&page_data, buf_out, size_out, false); 1564 if (ret < 0) { 1565 error_setg(errp, "dump: failed to write page data"); 1566 goto out; 1567 } 1568 #endif 1569 #ifdef CONFIG_SNAPPY 1570 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) && 1571 (snappy_compress((char *)buf, s->dump_info.page_size, 1572 (char *)buf_out, &size_out) == SNAPPY_OK) && 1573 (size_out < s->dump_info.page_size)) { 1574 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY); 1575 pd.size = cpu_to_dump32(s, size_out); 1576 1577 ret = write_cache(&page_data, buf_out, size_out, false); 1578 if (ret < 0) { 1579 error_setg(errp, "dump: failed to write page data"); 1580 goto out; 1581 } 1582 #endif 1583 } else { 1584 /* 1585 * fall back to save in plaintext, size_out should be 1586 * assigned the target's page size 1587 */ 1588 pd.flags = cpu_to_dump32(s, 0); 1589 size_out = s->dump_info.page_size; 1590 pd.size = cpu_to_dump32(s, size_out); 1591 1592 ret = write_cache(&page_data, buf, 1593 s->dump_info.page_size, false); 1594 if (ret < 0) { 1595 error_setg(errp, "dump: failed to write page data"); 1596 goto out; 1597 } 1598 } 1599 1600 /* get and write page desc here */ 1601 pd.page_flags = cpu_to_dump64(s, 0); 1602 pd.offset = cpu_to_dump64(s, offset_data); 1603 offset_data += size_out; 1604 1605 ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false); 1606 if (ret < 0) { 1607 error_setg(errp, "dump: failed to write page desc"); 1608 goto out; 1609 } 1610 } 1611 s->written_size += s->dump_info.page_size; 1612 } 1613 1614 ret = write_cache(&page_desc, NULL, 0, true); 1615 if (ret < 0) { 1616 error_setg(errp, "dump: failed to sync cache for page_desc"); 1617 goto out; 1618 } 1619 ret = write_cache(&page_data, NULL, 0, true); 1620 if (ret < 0) { 1621 error_setg(errp, "dump: failed to sync cache for page_data"); 1622 goto out; 1623 } 1624 1625 out: 1626 free_data_cache(&page_desc); 1627 free_data_cache(&page_data); 1628 1629 #ifdef CONFIG_LZO 1630 g_free(wrkmem); 1631 #endif 1632 1633 g_free(buf_out); 1634 } 1635 1636 static void create_kdump_vmcore(DumpState *s, Error **errp) 1637 { 1638 ERRP_GUARD(); 1639 int ret; 1640 1641 /* 1642 * the kdump-compressed format is: 1643 * File offset 1644 * +------------------------------------------+ 0x0 1645 * | main header (struct disk_dump_header) | 1646 * |------------------------------------------+ block 1 1647 * | sub header (struct kdump_sub_header) | 1648 * |------------------------------------------+ block 2 1649 * | 1st-dump_bitmap | 1650 * |------------------------------------------+ block 2 + X blocks 1651 * | 2nd-dump_bitmap | (aligned by block) 1652 * |------------------------------------------+ block 2 + 2 * X blocks 1653 * | page desc for pfn 0 (struct page_desc) | (aligned by block) 1654 * | page desc for pfn 1 (struct page_desc) | 1655 * | : | 1656 * |------------------------------------------| (not aligned by block) 1657 * | page data (pfn 0) | 1658 * | page data (pfn 1) | 1659 * | : | 1660 * +------------------------------------------+ 1661 */ 1662 1663 ret = write_start_flat_header(s); 1664 if (ret < 0) { 1665 error_setg(errp, "dump: failed to write start flat header"); 1666 return; 1667 } 1668 1669 write_dump_header(s, errp); 1670 if (*errp) { 1671 return; 1672 } 1673 1674 write_dump_bitmap(s, errp); 1675 if (*errp) { 1676 return; 1677 } 1678 1679 write_dump_pages(s, errp); 1680 if (*errp) { 1681 return; 1682 } 1683 1684 ret = write_end_flat_header(s); 1685 if (ret < 0) { 1686 error_setg(errp, "dump: failed to write end flat header"); 1687 return; 1688 } 1689 } 1690 1691 static int validate_start_block(DumpState *s) 1692 { 1693 GuestPhysBlock *block; 1694 1695 if (!dump_has_filter(s)) { 1696 return 0; 1697 } 1698 1699 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 1700 /* This block is out of the range */ 1701 if (block->target_start >= s->filter_area_begin + s->filter_area_length || 1702 block->target_end <= s->filter_area_begin) { 1703 continue; 1704 } 1705 return 0; 1706 } 1707 1708 return -1; 1709 } 1710 1711 static void get_max_mapnr(DumpState *s) 1712 { 1713 GuestPhysBlock *last_block; 1714 1715 last_block = QTAILQ_LAST(&s->guest_phys_blocks.head); 1716 s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end); 1717 } 1718 1719 static DumpState dump_state_global = { .status = DUMP_STATUS_NONE }; 1720 1721 static void dump_state_prepare(DumpState *s) 1722 { 1723 /* zero the struct, setting status to active */ 1724 *s = (DumpState) { .status = DUMP_STATUS_ACTIVE }; 1725 } 1726 1727 bool qemu_system_dump_in_progress(void) 1728 { 1729 DumpState *state = &dump_state_global; 1730 return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE); 1731 } 1732 1733 /* 1734 * calculate total size of memory to be dumped (taking filter into 1735 * account.) 1736 */ 1737 static int64_t dump_calculate_size(DumpState *s) 1738 { 1739 GuestPhysBlock *block; 1740 int64_t total = 0; 1741 1742 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 1743 total += dump_filtered_memblock_size(block, 1744 s->filter_area_begin, 1745 s->filter_area_length); 1746 } 1747 1748 return total; 1749 } 1750 1751 static void vmcoreinfo_update_phys_base(DumpState *s) 1752 { 1753 uint64_t size, note_head_size, name_size, phys_base; 1754 char **lines; 1755 uint8_t *vmci; 1756 size_t i; 1757 1758 if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1759 return; 1760 } 1761 1762 get_note_sizes(s, s->guest_note, ¬e_head_size, &name_size, &size); 1763 note_head_size = ROUND_UP(note_head_size, 4); 1764 1765 vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4); 1766 *(vmci + size) = '\0'; 1767 1768 lines = g_strsplit((char *)vmci, "\n", -1); 1769 for (i = 0; lines[i]; i++) { 1770 const char *prefix = NULL; 1771 1772 if (s->dump_info.d_machine == EM_X86_64) { 1773 prefix = "NUMBER(phys_base)="; 1774 } else if (s->dump_info.d_machine == EM_AARCH64) { 1775 prefix = "NUMBER(PHYS_OFFSET)="; 1776 } 1777 1778 if (prefix && g_str_has_prefix(lines[i], prefix)) { 1779 if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16, 1780 &phys_base) < 0) { 1781 warn_report("Failed to read %s", prefix); 1782 } else { 1783 s->dump_info.phys_base = phys_base; 1784 } 1785 break; 1786 } 1787 } 1788 1789 g_strfreev(lines); 1790 } 1791 1792 static void dump_init(DumpState *s, int fd, bool has_format, 1793 DumpGuestMemoryFormat format, bool paging, bool has_filter, 1794 int64_t begin, int64_t length, bool kdump_raw, 1795 Error **errp) 1796 { 1797 ERRP_GUARD(); 1798 VMCoreInfoState *vmci = vmcoreinfo_find(); 1799 CPUState *cpu; 1800 int nr_cpus; 1801 int ret; 1802 1803 s->has_format = has_format; 1804 s->format = format; 1805 s->written_size = 0; 1806 s->kdump_raw = kdump_raw; 1807 1808 /* kdump-compressed is conflict with paging and filter */ 1809 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1810 assert(!paging && !has_filter); 1811 } 1812 1813 if (runstate_is_running()) { 1814 vm_stop(RUN_STATE_SAVE_VM); 1815 s->resume = true; 1816 } else { 1817 s->resume = false; 1818 } 1819 1820 /* If we use KVM, we should synchronize the registers before we get dump 1821 * info or physmap info. 1822 */ 1823 cpu_synchronize_all_states(); 1824 nr_cpus = 0; 1825 CPU_FOREACH(cpu) { 1826 nr_cpus++; 1827 } 1828 1829 s->fd = fd; 1830 if (has_filter && !length) { 1831 error_setg(errp, QERR_INVALID_PARAMETER, "length"); 1832 goto cleanup; 1833 } 1834 s->filter_area_begin = begin; 1835 s->filter_area_length = length; 1836 1837 /* First index is 0, it's the special null name */ 1838 s->string_table_buf = g_array_new(FALSE, TRUE, 1); 1839 /* 1840 * Allocate the null name, due to the clearing option set to true 1841 * it will be 0. 1842 */ 1843 g_array_set_size(s->string_table_buf, 1); 1844 1845 memory_mapping_list_init(&s->list); 1846 1847 guest_phys_blocks_init(&s->guest_phys_blocks); 1848 guest_phys_blocks_append(&s->guest_phys_blocks); 1849 s->total_size = dump_calculate_size(s); 1850 #ifdef DEBUG_DUMP_GUEST_MEMORY 1851 fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size); 1852 #endif 1853 1854 /* it does not make sense to dump non-existent memory */ 1855 if (!s->total_size) { 1856 error_setg(errp, "dump: no guest memory to dump"); 1857 goto cleanup; 1858 } 1859 1860 /* Is the filter filtering everything? */ 1861 if (validate_start_block(s) == -1) { 1862 error_setg(errp, QERR_INVALID_PARAMETER, "begin"); 1863 goto cleanup; 1864 } 1865 1866 /* get dump info: endian, class and architecture. 1867 * If the target architecture is not supported, cpu_get_dump_info() will 1868 * return -1. 1869 */ 1870 ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks); 1871 if (ret < 0) { 1872 error_setg(errp, 1873 "dumping guest memory is not supported on this target"); 1874 goto cleanup; 1875 } 1876 1877 if (!s->dump_info.page_size) { 1878 s->dump_info.page_size = qemu_target_page_size(); 1879 } 1880 1881 s->note_size = cpu_get_note_size(s->dump_info.d_class, 1882 s->dump_info.d_machine, nr_cpus); 1883 assert(s->note_size >= 0); 1884 1885 /* 1886 * The goal of this block is to (a) update the previously guessed 1887 * phys_base, (b) copy the guest note out of the guest. 1888 * Failure to do so is not fatal for dumping. 1889 */ 1890 if (vmci) { 1891 uint64_t addr, note_head_size, name_size, desc_size; 1892 uint32_t size; 1893 uint16_t guest_format; 1894 1895 note_head_size = dump_is_64bit(s) ? 1896 sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr); 1897 1898 guest_format = le16_to_cpu(vmci->vmcoreinfo.guest_format); 1899 size = le32_to_cpu(vmci->vmcoreinfo.size); 1900 addr = le64_to_cpu(vmci->vmcoreinfo.paddr); 1901 if (!vmci->has_vmcoreinfo) { 1902 warn_report("guest note is not present"); 1903 } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) { 1904 warn_report("guest note size is invalid: %" PRIu32, size); 1905 } else if (guest_format != FW_CFG_VMCOREINFO_FORMAT_ELF) { 1906 warn_report("guest note format is unsupported: %" PRIu16, guest_format); 1907 } else { 1908 s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */ 1909 cpu_physical_memory_read(addr, s->guest_note, size); 1910 1911 get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size); 1912 s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size, 1913 desc_size); 1914 if (name_size > MAX_GUEST_NOTE_SIZE || 1915 desc_size > MAX_GUEST_NOTE_SIZE || 1916 s->guest_note_size > size) { 1917 warn_report("Invalid guest note header"); 1918 g_free(s->guest_note); 1919 s->guest_note = NULL; 1920 } else { 1921 vmcoreinfo_update_phys_base(s); 1922 s->note_size += s->guest_note_size; 1923 } 1924 } 1925 } 1926 1927 /* get memory mapping */ 1928 if (paging) { 1929 qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, errp); 1930 if (*errp) { 1931 goto cleanup; 1932 } 1933 } else { 1934 qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks); 1935 } 1936 1937 s->nr_cpus = nr_cpus; 1938 1939 get_max_mapnr(s); 1940 1941 uint64_t tmp; 1942 tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), 1943 s->dump_info.page_size); 1944 s->len_dump_bitmap = tmp * s->dump_info.page_size; 1945 1946 /* init for kdump-compressed format */ 1947 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1948 switch (format) { 1949 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB: 1950 s->flag_compress = DUMP_DH_COMPRESSED_ZLIB; 1951 break; 1952 1953 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO: 1954 #ifdef CONFIG_LZO 1955 if (lzo_init() != LZO_E_OK) { 1956 error_setg(errp, "failed to initialize the LZO library"); 1957 goto cleanup; 1958 } 1959 #endif 1960 s->flag_compress = DUMP_DH_COMPRESSED_LZO; 1961 break; 1962 1963 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY: 1964 s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY; 1965 break; 1966 1967 default: 1968 s->flag_compress = 0; 1969 } 1970 1971 return; 1972 } 1973 1974 if (dump_has_filter(s)) { 1975 memory_mapping_filter(&s->list, s->filter_area_begin, s->filter_area_length); 1976 } 1977 1978 /* 1979 * The first section header is always a special one in which most 1980 * fields are 0. The section header string table is also always 1981 * set. 1982 */ 1983 s->shdr_num = 2; 1984 1985 /* 1986 * Adds the number of architecture sections to shdr_num and sets 1987 * elf_section_data_size so we know the offsets and sizes of all 1988 * parts. 1989 */ 1990 if (s->dump_info.arch_sections_add_fn) { 1991 s->dump_info.arch_sections_add_fn(s); 1992 } 1993 1994 /* 1995 * calculate shdr_num so we know the offsets and sizes of all 1996 * parts. 1997 * Calculate phdr_num 1998 * 1999 * The absolute maximum amount of phdrs is UINT32_MAX - 1 as 2000 * sh_info is 32 bit. There's special handling once we go over 2001 * UINT16_MAX - 1 but that is handled in the ehdr and section 2002 * code. 2003 */ 2004 s->phdr_num = 1; /* Reserve PT_NOTE */ 2005 if (s->list.num <= UINT32_MAX - 1) { 2006 s->phdr_num += s->list.num; 2007 } else { 2008 s->phdr_num = UINT32_MAX; 2009 } 2010 2011 /* 2012 * Now that the number of section and program headers is known we 2013 * can calculate the offsets of the headers and data. 2014 */ 2015 if (dump_is_64bit(s)) { 2016 s->shdr_offset = sizeof(Elf64_Ehdr); 2017 s->phdr_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; 2018 s->note_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; 2019 } else { 2020 s->shdr_offset = sizeof(Elf32_Ehdr); 2021 s->phdr_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; 2022 s->note_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; 2023 } 2024 s->memory_offset = s->note_offset + s->note_size; 2025 s->section_offset = s->memory_offset + s->total_size; 2026 2027 return; 2028 2029 cleanup: 2030 dump_cleanup(s); 2031 } 2032 2033 /* this operation might be time consuming. */ 2034 static void dump_process(DumpState *s, Error **errp) 2035 { 2036 ERRP_GUARD(); 2037 DumpQueryResult *result = NULL; 2038 2039 if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { 2040 create_win_dump(s, errp); 2041 } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 2042 create_kdump_vmcore(s, errp); 2043 } else { 2044 create_vmcore(s, errp); 2045 } 2046 2047 /* make sure status is written after written_size updates */ 2048 smp_wmb(); 2049 qatomic_set(&s->status, 2050 (*errp ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED)); 2051 2052 /* send DUMP_COMPLETED message (unconditionally) */ 2053 result = qmp_query_dump(NULL); 2054 /* should never fail */ 2055 assert(result); 2056 qapi_event_send_dump_completed(result, 2057 *errp ? error_get_pretty(*errp) : NULL); 2058 qapi_free_DumpQueryResult(result); 2059 2060 dump_cleanup(s); 2061 } 2062 2063 static void *dump_thread(void *data) 2064 { 2065 DumpState *s = (DumpState *)data; 2066 dump_process(s, NULL); 2067 return NULL; 2068 } 2069 2070 DumpQueryResult *qmp_query_dump(Error **errp) 2071 { 2072 DumpQueryResult *result = g_new(DumpQueryResult, 1); 2073 DumpState *state = &dump_state_global; 2074 result->status = qatomic_read(&state->status); 2075 /* make sure we are reading status and written_size in order */ 2076 smp_rmb(); 2077 result->completed = state->written_size; 2078 result->total = state->total_size; 2079 return result; 2080 } 2081 2082 void qmp_dump_guest_memory(bool paging, const char *protocol, 2083 bool has_detach, bool detach, 2084 bool has_begin, int64_t begin, 2085 bool has_length, int64_t length, 2086 bool has_format, DumpGuestMemoryFormat format, 2087 Error **errp) 2088 { 2089 ERRP_GUARD(); 2090 const char *p; 2091 int fd = -1; 2092 DumpState *s; 2093 bool detach_p = false; 2094 bool kdump_raw = false; 2095 2096 if (runstate_check(RUN_STATE_INMIGRATE)) { 2097 error_setg(errp, "Dump not allowed during incoming migration."); 2098 return; 2099 } 2100 2101 /* if there is a dump in background, we should wait until the dump 2102 * finished */ 2103 if (qemu_system_dump_in_progress()) { 2104 error_setg(errp, "There is a dump in process, please wait."); 2105 return; 2106 } 2107 2108 /* 2109 * externally, we represent kdump-raw-* as separate formats, but internally 2110 * they are handled the same, except for the "raw" flag 2111 */ 2112 if (has_format) { 2113 switch (format) { 2114 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_ZLIB: 2115 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB; 2116 kdump_raw = true; 2117 break; 2118 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_LZO: 2119 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO; 2120 kdump_raw = true; 2121 break; 2122 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_SNAPPY: 2123 format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY; 2124 kdump_raw = true; 2125 break; 2126 default: 2127 break; 2128 } 2129 } 2130 2131 /* 2132 * kdump-compressed format need the whole memory dumped, so paging or 2133 * filter is not supported here. 2134 */ 2135 if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) && 2136 (paging || has_begin || has_length)) { 2137 error_setg(errp, "kdump-compressed format doesn't support paging or " 2138 "filter"); 2139 return; 2140 } 2141 if (has_begin && !has_length) { 2142 error_setg(errp, QERR_MISSING_PARAMETER, "length"); 2143 return; 2144 } 2145 if (!has_begin && has_length) { 2146 error_setg(errp, QERR_MISSING_PARAMETER, "begin"); 2147 return; 2148 } 2149 if (has_detach) { 2150 detach_p = detach; 2151 } 2152 2153 /* check whether lzo/snappy is supported */ 2154 #ifndef CONFIG_LZO 2155 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) { 2156 error_setg(errp, "kdump-lzo is not available now"); 2157 return; 2158 } 2159 #endif 2160 2161 #ifndef CONFIG_SNAPPY 2162 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) { 2163 error_setg(errp, "kdump-snappy is not available now"); 2164 return; 2165 } 2166 #endif 2167 2168 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP 2169 && !win_dump_available(errp)) { 2170 return; 2171 } 2172 2173 #if !defined(WIN32) 2174 if (strstart(protocol, "fd:", &p)) { 2175 fd = monitor_get_fd(monitor_cur(), p, errp); 2176 if (fd == -1) { 2177 return; 2178 } 2179 } 2180 #endif 2181 2182 if (strstart(protocol, "file:", &p)) { 2183 fd = qemu_open_old(p, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR); 2184 if (fd < 0) { 2185 error_setg_file_open(errp, errno, p); 2186 return; 2187 } 2188 } 2189 2190 if (fd == -1) { 2191 error_setg(errp, QERR_INVALID_PARAMETER, "protocol"); 2192 return; 2193 } 2194 if (kdump_raw && lseek(fd, 0, SEEK_CUR) == (off_t) -1) { 2195 error_setg(errp, "kdump-raw formats require a seekable file"); 2196 return; 2197 } 2198 2199 if (!dump_migration_blocker) { 2200 error_setg(&dump_migration_blocker, 2201 "Live migration disabled: dump-guest-memory in progress"); 2202 } 2203 2204 /* 2205 * Allows even for -only-migratable, but forbid migration during the 2206 * process of dump guest memory. 2207 */ 2208 if (migrate_add_blocker_internal(&dump_migration_blocker, errp)) { 2209 /* Remember to release the fd before passing it over to dump state */ 2210 close(fd); 2211 return; 2212 } 2213 2214 s = &dump_state_global; 2215 dump_state_prepare(s); 2216 2217 dump_init(s, fd, has_format, format, paging, has_begin, 2218 begin, length, kdump_raw, errp); 2219 if (*errp) { 2220 qatomic_set(&s->status, DUMP_STATUS_FAILED); 2221 return; 2222 } 2223 2224 if (detach_p) { 2225 /* detached dump */ 2226 s->detached = true; 2227 qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread, 2228 s, QEMU_THREAD_DETACHED); 2229 } else { 2230 /* sync dump */ 2231 dump_process(s, errp); 2232 } 2233 } 2234 2235 DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp) 2236 { 2237 DumpGuestMemoryCapability *cap = 2238 g_new0(DumpGuestMemoryCapability, 1); 2239 DumpGuestMemoryFormatList **tail = &cap->formats; 2240 2241 /* elf is always available */ 2242 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF); 2243 2244 /* kdump-zlib is always available */ 2245 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB); 2246 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_ZLIB); 2247 2248 /* add new item if kdump-lzo is available */ 2249 #ifdef CONFIG_LZO 2250 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO); 2251 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_LZO); 2252 #endif 2253 2254 /* add new item if kdump-snappy is available */ 2255 #ifdef CONFIG_SNAPPY 2256 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY); 2257 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_RAW_SNAPPY); 2258 #endif 2259 2260 if (win_dump_available(NULL)) { 2261 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP); 2262 } 2263 2264 return cap; 2265 } 2266