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 "exec/hwaddr.h" 18 #include "monitor/monitor.h" 19 #include "sysemu/kvm.h" 20 #include "sysemu/dump.h" 21 #include "sysemu/memory_mapping.h" 22 #include "sysemu/runstate.h" 23 #include "sysemu/cpus.h" 24 #include "qapi/error.h" 25 #include "qapi/qapi-commands-dump.h" 26 #include "qapi/qapi-events-dump.h" 27 #include "qapi/qmp/qerror.h" 28 #include "qemu/error-report.h" 29 #include "qemu/main-loop.h" 30 #include "hw/misc/vmcoreinfo.h" 31 #include "migration/blocker.h" 32 33 #ifdef TARGET_X86_64 34 #include "win_dump.h" 35 #endif 36 37 #include <zlib.h> 38 #ifdef CONFIG_LZO 39 #include <lzo/lzo1x.h> 40 #endif 41 #ifdef CONFIG_SNAPPY 42 #include <snappy-c.h> 43 #endif 44 #ifndef ELF_MACHINE_UNAME 45 #define ELF_MACHINE_UNAME "Unknown" 46 #endif 47 48 #define MAX_GUEST_NOTE_SIZE (1 << 20) /* 1MB should be enough */ 49 50 static Error *dump_migration_blocker; 51 52 #define ELF_NOTE_SIZE(hdr_size, name_size, desc_size) \ 53 ((DIV_ROUND_UP((hdr_size), 4) + \ 54 DIV_ROUND_UP((name_size), 4) + \ 55 DIV_ROUND_UP((desc_size), 4)) * 4) 56 57 static inline bool dump_is_64bit(DumpState *s) 58 { 59 return s->dump_info.d_class == ELFCLASS64; 60 } 61 62 static inline bool dump_has_filter(DumpState *s) 63 { 64 return s->filter_area_length > 0; 65 } 66 67 uint16_t cpu_to_dump16(DumpState *s, uint16_t val) 68 { 69 if (s->dump_info.d_endian == ELFDATA2LSB) { 70 val = cpu_to_le16(val); 71 } else { 72 val = cpu_to_be16(val); 73 } 74 75 return val; 76 } 77 78 uint32_t cpu_to_dump32(DumpState *s, uint32_t val) 79 { 80 if (s->dump_info.d_endian == ELFDATA2LSB) { 81 val = cpu_to_le32(val); 82 } else { 83 val = cpu_to_be32(val); 84 } 85 86 return val; 87 } 88 89 uint64_t cpu_to_dump64(DumpState *s, uint64_t val) 90 { 91 if (s->dump_info.d_endian == ELFDATA2LSB) { 92 val = cpu_to_le64(val); 93 } else { 94 val = cpu_to_be64(val); 95 } 96 97 return val; 98 } 99 100 static int dump_cleanup(DumpState *s) 101 { 102 guest_phys_blocks_free(&s->guest_phys_blocks); 103 memory_mapping_list_free(&s->list); 104 close(s->fd); 105 g_free(s->guest_note); 106 g_array_unref(s->string_table_buf); 107 s->guest_note = NULL; 108 if (s->resume) { 109 if (s->detached) { 110 qemu_mutex_lock_iothread(); 111 } 112 vm_start(); 113 if (s->detached) { 114 qemu_mutex_unlock_iothread(); 115 } 116 } 117 migrate_del_blocker(dump_migration_blocker); 118 119 return 0; 120 } 121 122 static int fd_write_vmcore(const void *buf, size_t size, void *opaque) 123 { 124 DumpState *s = opaque; 125 size_t written_size; 126 127 written_size = qemu_write_full(s->fd, buf, size); 128 if (written_size != size) { 129 return -errno; 130 } 131 132 return 0; 133 } 134 135 static void prepare_elf64_header(DumpState *s, Elf64_Ehdr *elf_header) 136 { 137 /* 138 * phnum in the elf header is 16 bit, if we have more segments we 139 * set phnum to PN_XNUM and write the real number of segments to a 140 * special section. 141 */ 142 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 143 144 memset(elf_header, 0, sizeof(Elf64_Ehdr)); 145 memcpy(elf_header, ELFMAG, SELFMAG); 146 elf_header->e_ident[EI_CLASS] = ELFCLASS64; 147 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 148 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 149 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 150 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 151 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 152 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 153 elf_header->e_phoff = cpu_to_dump64(s, s->phdr_offset); 154 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); 155 elf_header->e_phnum = cpu_to_dump16(s, phnum); 156 elf_header->e_shoff = cpu_to_dump64(s, s->shdr_offset); 157 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); 158 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 159 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 160 } 161 162 static void prepare_elf32_header(DumpState *s, Elf32_Ehdr *elf_header) 163 { 164 /* 165 * phnum in the elf header is 16 bit, if we have more segments we 166 * set phnum to PN_XNUM and write the real number of segments to a 167 * special section. 168 */ 169 uint16_t phnum = MIN(s->phdr_num, PN_XNUM); 170 171 memset(elf_header, 0, sizeof(Elf32_Ehdr)); 172 memcpy(elf_header, ELFMAG, SELFMAG); 173 elf_header->e_ident[EI_CLASS] = ELFCLASS32; 174 elf_header->e_ident[EI_DATA] = s->dump_info.d_endian; 175 elf_header->e_ident[EI_VERSION] = EV_CURRENT; 176 elf_header->e_type = cpu_to_dump16(s, ET_CORE); 177 elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine); 178 elf_header->e_version = cpu_to_dump32(s, EV_CURRENT); 179 elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); 180 elf_header->e_phoff = cpu_to_dump32(s, s->phdr_offset); 181 elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); 182 elf_header->e_phnum = cpu_to_dump16(s, phnum); 183 elf_header->e_shoff = cpu_to_dump32(s, s->shdr_offset); 184 elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); 185 elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num); 186 elf_header->e_shstrndx = cpu_to_dump16(s, s->shdr_num - 1); 187 } 188 189 static void write_elf_header(DumpState *s, Error **errp) 190 { 191 Elf32_Ehdr elf32_header; 192 Elf64_Ehdr elf64_header; 193 size_t header_size; 194 void *header_ptr; 195 int ret; 196 197 /* The NULL header and the shstrtab are always defined */ 198 assert(s->shdr_num >= 2); 199 if (dump_is_64bit(s)) { 200 prepare_elf64_header(s, &elf64_header); 201 header_size = sizeof(elf64_header); 202 header_ptr = &elf64_header; 203 } else { 204 prepare_elf32_header(s, &elf32_header); 205 header_size = sizeof(elf32_header); 206 header_ptr = &elf32_header; 207 } 208 209 ret = fd_write_vmcore(header_ptr, header_size, s); 210 if (ret < 0) { 211 error_setg_errno(errp, -ret, "dump: failed to write elf header"); 212 } 213 } 214 215 static void write_elf64_load(DumpState *s, MemoryMapping *memory_mapping, 216 int phdr_index, hwaddr offset, 217 hwaddr filesz, Error **errp) 218 { 219 Elf64_Phdr phdr; 220 int ret; 221 222 memset(&phdr, 0, sizeof(Elf64_Phdr)); 223 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 224 phdr.p_offset = cpu_to_dump64(s, offset); 225 phdr.p_paddr = cpu_to_dump64(s, memory_mapping->phys_addr); 226 phdr.p_filesz = cpu_to_dump64(s, filesz); 227 phdr.p_memsz = cpu_to_dump64(s, memory_mapping->length); 228 phdr.p_vaddr = cpu_to_dump64(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 229 230 assert(memory_mapping->length >= filesz); 231 232 ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s); 233 if (ret < 0) { 234 error_setg_errno(errp, -ret, 235 "dump: failed to write program header table"); 236 } 237 } 238 239 static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, 240 int phdr_index, hwaddr offset, 241 hwaddr filesz, Error **errp) 242 { 243 Elf32_Phdr phdr; 244 int ret; 245 246 memset(&phdr, 0, sizeof(Elf32_Phdr)); 247 phdr.p_type = cpu_to_dump32(s, PT_LOAD); 248 phdr.p_offset = cpu_to_dump32(s, offset); 249 phdr.p_paddr = cpu_to_dump32(s, memory_mapping->phys_addr); 250 phdr.p_filesz = cpu_to_dump32(s, filesz); 251 phdr.p_memsz = cpu_to_dump32(s, memory_mapping->length); 252 phdr.p_vaddr = 253 cpu_to_dump32(s, memory_mapping->virt_addr) ?: phdr.p_paddr; 254 255 assert(memory_mapping->length >= filesz); 256 257 ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s); 258 if (ret < 0) { 259 error_setg_errno(errp, -ret, 260 "dump: failed to write program header table"); 261 } 262 } 263 264 static void prepare_elf64_phdr_note(DumpState *s, Elf64_Phdr *phdr) 265 { 266 memset(phdr, 0, sizeof(*phdr)); 267 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 268 phdr->p_offset = cpu_to_dump64(s, s->note_offset); 269 phdr->p_paddr = 0; 270 phdr->p_filesz = cpu_to_dump64(s, s->note_size); 271 phdr->p_memsz = cpu_to_dump64(s, s->note_size); 272 phdr->p_vaddr = 0; 273 } 274 275 static inline int cpu_index(CPUState *cpu) 276 { 277 return cpu->cpu_index + 1; 278 } 279 280 static void write_guest_note(WriteCoreDumpFunction f, DumpState *s, 281 Error **errp) 282 { 283 int ret; 284 285 if (s->guest_note) { 286 ret = f(s->guest_note, s->guest_note_size, s); 287 if (ret < 0) { 288 error_setg(errp, "dump: failed to write guest note"); 289 } 290 } 291 } 292 293 static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, 294 Error **errp) 295 { 296 CPUState *cpu; 297 int ret; 298 int id; 299 300 CPU_FOREACH(cpu) { 301 id = cpu_index(cpu); 302 ret = cpu_write_elf64_note(f, cpu, id, s); 303 if (ret < 0) { 304 error_setg(errp, "dump: failed to write elf notes"); 305 return; 306 } 307 } 308 309 CPU_FOREACH(cpu) { 310 ret = cpu_write_elf64_qemunote(f, cpu, s); 311 if (ret < 0) { 312 error_setg(errp, "dump: failed to write CPU status"); 313 return; 314 } 315 } 316 317 write_guest_note(f, s, errp); 318 } 319 320 static void prepare_elf32_phdr_note(DumpState *s, Elf32_Phdr *phdr) 321 { 322 memset(phdr, 0, sizeof(*phdr)); 323 phdr->p_type = cpu_to_dump32(s, PT_NOTE); 324 phdr->p_offset = cpu_to_dump32(s, s->note_offset); 325 phdr->p_paddr = 0; 326 phdr->p_filesz = cpu_to_dump32(s, s->note_size); 327 phdr->p_memsz = cpu_to_dump32(s, s->note_size); 328 phdr->p_vaddr = 0; 329 } 330 331 static void write_elf32_notes(WriteCoreDumpFunction f, DumpState *s, 332 Error **errp) 333 { 334 CPUState *cpu; 335 int ret; 336 int id; 337 338 CPU_FOREACH(cpu) { 339 id = cpu_index(cpu); 340 ret = cpu_write_elf32_note(f, cpu, id, s); 341 if (ret < 0) { 342 error_setg(errp, "dump: failed to write elf notes"); 343 return; 344 } 345 } 346 347 CPU_FOREACH(cpu) { 348 ret = cpu_write_elf32_qemunote(f, cpu, s); 349 if (ret < 0) { 350 error_setg(errp, "dump: failed to write CPU status"); 351 return; 352 } 353 } 354 355 write_guest_note(f, s, errp); 356 } 357 358 static void write_elf_phdr_note(DumpState *s, Error **errp) 359 { 360 ERRP_GUARD(); 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 ERRP_GUARD(); 777 778 if (s->elf_section_data_size) { 779 s->elf_section_data = g_malloc0(s->elf_section_data_size); 780 } 781 782 /* Adds the architecture defined section data to s->elf_section_data */ 783 if (s->dump_info.arch_sections_write_fn && 784 s->elf_section_data_size) { 785 rc = s->dump_info.arch_sections_write_fn(s, s->elf_section_data); 786 if (rc) { 787 error_setg_errno(errp, rc, 788 "dump: failed to get arch section data"); 789 g_free(s->elf_section_data); 790 return; 791 } 792 } 793 794 /* write sections to vmcore */ 795 write_elf_sections(s, errp); 796 } 797 798 static void create_vmcore(DumpState *s, Error **errp) 799 { 800 ERRP_GUARD(); 801 802 dump_begin(s, errp); 803 if (*errp) { 804 return; 805 } 806 807 /* Iterate over memory and dump it to file */ 808 dump_iterate(s, errp); 809 if (*errp) { 810 return; 811 } 812 813 /* Write the section data */ 814 dump_end(s, errp); 815 } 816 817 static int write_start_flat_header(int fd) 818 { 819 MakedumpfileHeader *mh; 820 int ret = 0; 821 822 QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER); 823 mh = g_malloc0(MAX_SIZE_MDF_HEADER); 824 825 memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE, 826 MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE)); 827 828 mh->type = cpu_to_be64(TYPE_FLAT_HEADER); 829 mh->version = cpu_to_be64(VERSION_FLAT_HEADER); 830 831 size_t written_size; 832 written_size = qemu_write_full(fd, mh, MAX_SIZE_MDF_HEADER); 833 if (written_size != MAX_SIZE_MDF_HEADER) { 834 ret = -1; 835 } 836 837 g_free(mh); 838 return ret; 839 } 840 841 static int write_end_flat_header(int fd) 842 { 843 MakedumpfileDataHeader mdh; 844 845 mdh.offset = END_FLAG_FLAT_HEADER; 846 mdh.buf_size = END_FLAG_FLAT_HEADER; 847 848 size_t written_size; 849 written_size = qemu_write_full(fd, &mdh, sizeof(mdh)); 850 if (written_size != sizeof(mdh)) { 851 return -1; 852 } 853 854 return 0; 855 } 856 857 static int write_buffer(int fd, off_t offset, const void *buf, size_t size) 858 { 859 size_t written_size; 860 MakedumpfileDataHeader mdh; 861 862 mdh.offset = cpu_to_be64(offset); 863 mdh.buf_size = cpu_to_be64(size); 864 865 written_size = qemu_write_full(fd, &mdh, sizeof(mdh)); 866 if (written_size != sizeof(mdh)) { 867 return -1; 868 } 869 870 written_size = qemu_write_full(fd, buf, size); 871 if (written_size != size) { 872 return -1; 873 } 874 875 return 0; 876 } 877 878 static int buf_write_note(const void *buf, size_t size, void *opaque) 879 { 880 DumpState *s = opaque; 881 882 /* note_buf is not enough */ 883 if (s->note_buf_offset + size > s->note_size) { 884 return -1; 885 } 886 887 memcpy(s->note_buf + s->note_buf_offset, buf, size); 888 889 s->note_buf_offset += size; 890 891 return 0; 892 } 893 894 /* 895 * This function retrieves various sizes from an elf header. 896 * 897 * @note has to be a valid ELF note. The return sizes are unmodified 898 * (not padded or rounded up to be multiple of 4). 899 */ 900 static void get_note_sizes(DumpState *s, const void *note, 901 uint64_t *note_head_size, 902 uint64_t *name_size, 903 uint64_t *desc_size) 904 { 905 uint64_t note_head_sz; 906 uint64_t name_sz; 907 uint64_t desc_sz; 908 909 if (dump_is_64bit(s)) { 910 const Elf64_Nhdr *hdr = note; 911 note_head_sz = sizeof(Elf64_Nhdr); 912 name_sz = tswap64(hdr->n_namesz); 913 desc_sz = tswap64(hdr->n_descsz); 914 } else { 915 const Elf32_Nhdr *hdr = note; 916 note_head_sz = sizeof(Elf32_Nhdr); 917 name_sz = tswap32(hdr->n_namesz); 918 desc_sz = tswap32(hdr->n_descsz); 919 } 920 921 if (note_head_size) { 922 *note_head_size = note_head_sz; 923 } 924 if (name_size) { 925 *name_size = name_sz; 926 } 927 if (desc_size) { 928 *desc_size = desc_sz; 929 } 930 } 931 932 static bool note_name_equal(DumpState *s, 933 const uint8_t *note, const char *name) 934 { 935 int len = strlen(name) + 1; 936 uint64_t head_size, name_size; 937 938 get_note_sizes(s, note, &head_size, &name_size, NULL); 939 head_size = ROUND_UP(head_size, 4); 940 941 return name_size == len && memcmp(note + head_size, name, len) == 0; 942 } 943 944 /* write common header, sub header and elf note to vmcore */ 945 static void create_header32(DumpState *s, Error **errp) 946 { 947 ERRP_GUARD(); 948 DiskDumpHeader32 *dh = NULL; 949 KdumpSubHeader32 *kh = NULL; 950 size_t size; 951 uint32_t block_size; 952 uint32_t sub_hdr_size; 953 uint32_t bitmap_blocks; 954 uint32_t status = 0; 955 uint64_t offset_note; 956 957 /* write common header, the version of kdump-compressed format is 6th */ 958 size = sizeof(DiskDumpHeader32); 959 dh = g_malloc0(size); 960 961 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 962 dh->header_version = cpu_to_dump32(s, 6); 963 block_size = s->dump_info.page_size; 964 dh->block_size = cpu_to_dump32(s, block_size); 965 sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size; 966 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 967 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 968 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 969 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 970 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 971 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 972 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 973 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 974 975 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 976 status |= DUMP_DH_COMPRESSED_ZLIB; 977 } 978 #ifdef CONFIG_LZO 979 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 980 status |= DUMP_DH_COMPRESSED_LZO; 981 } 982 #endif 983 #ifdef CONFIG_SNAPPY 984 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 985 status |= DUMP_DH_COMPRESSED_SNAPPY; 986 } 987 #endif 988 dh->status = cpu_to_dump32(s, status); 989 990 if (write_buffer(s->fd, 0, dh, size) < 0) { 991 error_setg(errp, "dump: failed to write disk dump header"); 992 goto out; 993 } 994 995 /* write sub header */ 996 size = sizeof(KdumpSubHeader32); 997 kh = g_malloc0(size); 998 999 /* 64bit max_mapnr_64 */ 1000 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1001 kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base); 1002 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1003 1004 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1005 if (s->guest_note && 1006 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1007 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1008 1009 get_note_sizes(s, s->guest_note, 1010 &hsize, &name_size, &size_vmcoreinfo_desc); 1011 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1012 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1013 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1014 kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc); 1015 } 1016 1017 kh->offset_note = cpu_to_dump64(s, offset_note); 1018 kh->note_size = cpu_to_dump32(s, s->note_size); 1019 1020 if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS * 1021 block_size, kh, size) < 0) { 1022 error_setg(errp, "dump: failed to write kdump sub header"); 1023 goto out; 1024 } 1025 1026 /* write note */ 1027 s->note_buf = g_malloc0(s->note_size); 1028 s->note_buf_offset = 0; 1029 1030 /* use s->note_buf to store notes temporarily */ 1031 write_elf32_notes(buf_write_note, s, errp); 1032 if (*errp) { 1033 goto out; 1034 } 1035 if (write_buffer(s->fd, offset_note, s->note_buf, 1036 s->note_size) < 0) { 1037 error_setg(errp, "dump: failed to write notes"); 1038 goto out; 1039 } 1040 1041 /* get offset of dump_bitmap */ 1042 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1043 block_size; 1044 1045 /* get offset of page */ 1046 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1047 block_size; 1048 1049 out: 1050 g_free(dh); 1051 g_free(kh); 1052 g_free(s->note_buf); 1053 } 1054 1055 /* write common header, sub header and elf note to vmcore */ 1056 static void create_header64(DumpState *s, Error **errp) 1057 { 1058 ERRP_GUARD(); 1059 DiskDumpHeader64 *dh = NULL; 1060 KdumpSubHeader64 *kh = NULL; 1061 size_t size; 1062 uint32_t block_size; 1063 uint32_t sub_hdr_size; 1064 uint32_t bitmap_blocks; 1065 uint32_t status = 0; 1066 uint64_t offset_note; 1067 1068 /* write common header, the version of kdump-compressed format is 6th */ 1069 size = sizeof(DiskDumpHeader64); 1070 dh = g_malloc0(size); 1071 1072 memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN); 1073 dh->header_version = cpu_to_dump32(s, 6); 1074 block_size = s->dump_info.page_size; 1075 dh->block_size = cpu_to_dump32(s, block_size); 1076 sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size; 1077 sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size); 1078 dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size); 1079 /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */ 1080 dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX)); 1081 dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus); 1082 bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2; 1083 dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks); 1084 strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine)); 1085 1086 if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) { 1087 status |= DUMP_DH_COMPRESSED_ZLIB; 1088 } 1089 #ifdef CONFIG_LZO 1090 if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) { 1091 status |= DUMP_DH_COMPRESSED_LZO; 1092 } 1093 #endif 1094 #ifdef CONFIG_SNAPPY 1095 if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) { 1096 status |= DUMP_DH_COMPRESSED_SNAPPY; 1097 } 1098 #endif 1099 dh->status = cpu_to_dump32(s, status); 1100 1101 if (write_buffer(s->fd, 0, dh, size) < 0) { 1102 error_setg(errp, "dump: failed to write disk dump header"); 1103 goto out; 1104 } 1105 1106 /* write sub header */ 1107 size = sizeof(KdumpSubHeader64); 1108 kh = g_malloc0(size); 1109 1110 /* 64bit max_mapnr_64 */ 1111 kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr); 1112 kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base); 1113 kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL); 1114 1115 offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size; 1116 if (s->guest_note && 1117 note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1118 uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo; 1119 1120 get_note_sizes(s, s->guest_note, 1121 &hsize, &name_size, &size_vmcoreinfo_desc); 1122 offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size + 1123 (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4; 1124 kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo); 1125 kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc); 1126 } 1127 1128 kh->offset_note = cpu_to_dump64(s, offset_note); 1129 kh->note_size = cpu_to_dump64(s, s->note_size); 1130 1131 if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS * 1132 block_size, kh, size) < 0) { 1133 error_setg(errp, "dump: failed to write kdump sub header"); 1134 goto out; 1135 } 1136 1137 /* write note */ 1138 s->note_buf = g_malloc0(s->note_size); 1139 s->note_buf_offset = 0; 1140 1141 /* use s->note_buf to store notes temporarily */ 1142 write_elf64_notes(buf_write_note, s, errp); 1143 if (*errp) { 1144 goto out; 1145 } 1146 1147 if (write_buffer(s->fd, offset_note, s->note_buf, 1148 s->note_size) < 0) { 1149 error_setg(errp, "dump: failed to write notes"); 1150 goto out; 1151 } 1152 1153 /* get offset of dump_bitmap */ 1154 s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) * 1155 block_size; 1156 1157 /* get offset of page */ 1158 s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) * 1159 block_size; 1160 1161 out: 1162 g_free(dh); 1163 g_free(kh); 1164 g_free(s->note_buf); 1165 } 1166 1167 static void write_dump_header(DumpState *s, Error **errp) 1168 { 1169 if (dump_is_64bit(s)) { 1170 create_header64(s, errp); 1171 } else { 1172 create_header32(s, errp); 1173 } 1174 } 1175 1176 static size_t dump_bitmap_get_bufsize(DumpState *s) 1177 { 1178 return s->dump_info.page_size; 1179 } 1180 1181 /* 1182 * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be 1183 * rewritten, so if need to set the first bit, set last_pfn and pfn to 0. 1184 * set_dump_bitmap will always leave the recently set bit un-sync. And setting 1185 * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into 1186 * vmcore, ie. synchronizing un-sync bit into vmcore. 1187 */ 1188 static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value, 1189 uint8_t *buf, DumpState *s) 1190 { 1191 off_t old_offset, new_offset; 1192 off_t offset_bitmap1, offset_bitmap2; 1193 uint32_t byte, bit; 1194 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1195 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1196 1197 /* should not set the previous place */ 1198 assert(last_pfn <= pfn); 1199 1200 /* 1201 * if the bit needed to be set is not cached in buf, flush the data in buf 1202 * to vmcore firstly. 1203 * making new_offset be bigger than old_offset can also sync remained data 1204 * into vmcore. 1205 */ 1206 old_offset = bitmap_bufsize * (last_pfn / bits_per_buf); 1207 new_offset = bitmap_bufsize * (pfn / bits_per_buf); 1208 1209 while (old_offset < new_offset) { 1210 /* calculate the offset and write dump_bitmap */ 1211 offset_bitmap1 = s->offset_dump_bitmap + old_offset; 1212 if (write_buffer(s->fd, offset_bitmap1, buf, 1213 bitmap_bufsize) < 0) { 1214 return -1; 1215 } 1216 1217 /* dump level 1 is chosen, so 1st and 2nd bitmap are same */ 1218 offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap + 1219 old_offset; 1220 if (write_buffer(s->fd, offset_bitmap2, buf, 1221 bitmap_bufsize) < 0) { 1222 return -1; 1223 } 1224 1225 memset(buf, 0, bitmap_bufsize); 1226 old_offset += bitmap_bufsize; 1227 } 1228 1229 /* get the exact place of the bit in the buf, and set it */ 1230 byte = (pfn % bits_per_buf) / CHAR_BIT; 1231 bit = (pfn % bits_per_buf) % CHAR_BIT; 1232 if (value) { 1233 buf[byte] |= 1u << bit; 1234 } else { 1235 buf[byte] &= ~(1u << bit); 1236 } 1237 1238 return 0; 1239 } 1240 1241 static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr) 1242 { 1243 int target_page_shift = ctz32(s->dump_info.page_size); 1244 1245 return (addr >> target_page_shift) - ARCH_PFN_OFFSET; 1246 } 1247 1248 static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn) 1249 { 1250 int target_page_shift = ctz32(s->dump_info.page_size); 1251 1252 return (pfn + ARCH_PFN_OFFSET) << target_page_shift; 1253 } 1254 1255 /* 1256 * Return the page frame number and the page content in *bufptr. bufptr can be 1257 * NULL. If not NULL, *bufptr must contains a target page size of pre-allocated 1258 * memory. This is not necessarily the memory returned. 1259 */ 1260 static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr, 1261 uint8_t **bufptr, DumpState *s) 1262 { 1263 GuestPhysBlock *block = *blockptr; 1264 uint32_t page_size = s->dump_info.page_size; 1265 uint8_t *buf = NULL, *hbuf; 1266 hwaddr addr; 1267 1268 /* block == NULL means the start of the iteration */ 1269 if (!block) { 1270 block = QTAILQ_FIRST(&s->guest_phys_blocks.head); 1271 *blockptr = block; 1272 addr = block->target_start; 1273 *pfnptr = dump_paddr_to_pfn(s, addr); 1274 } else { 1275 *pfnptr += 1; 1276 addr = dump_pfn_to_paddr(s, *pfnptr); 1277 } 1278 assert(block != NULL); 1279 1280 while (1) { 1281 if (addr >= block->target_start && addr < block->target_end) { 1282 size_t n = MIN(block->target_end - addr, page_size - addr % page_size); 1283 hbuf = block->host_addr + (addr - block->target_start); 1284 if (!buf) { 1285 if (n == page_size) { 1286 /* this is a whole target page, go for it */ 1287 assert(addr % page_size == 0); 1288 buf = hbuf; 1289 break; 1290 } else if (bufptr) { 1291 assert(*bufptr); 1292 buf = *bufptr; 1293 memset(buf, 0, page_size); 1294 } else { 1295 return true; 1296 } 1297 } 1298 1299 memcpy(buf + addr % page_size, hbuf, n); 1300 addr += n; 1301 if (addr % page_size == 0) { 1302 /* we filled up the page */ 1303 break; 1304 } 1305 } else { 1306 /* the next page is in the next block */ 1307 *blockptr = block = QTAILQ_NEXT(block, next); 1308 if (!block) { 1309 break; 1310 } 1311 1312 addr = block->target_start; 1313 /* are we still in the same page? */ 1314 if (dump_paddr_to_pfn(s, addr) != *pfnptr) { 1315 if (buf) { 1316 /* no, but we already filled something earlier, return it */ 1317 break; 1318 } else { 1319 /* else continue from there */ 1320 *pfnptr = dump_paddr_to_pfn(s, addr); 1321 } 1322 } 1323 } 1324 } 1325 1326 if (bufptr) { 1327 *bufptr = buf; 1328 } 1329 1330 return buf != NULL; 1331 } 1332 1333 static void write_dump_bitmap(DumpState *s, Error **errp) 1334 { 1335 int ret = 0; 1336 uint64_t last_pfn, pfn; 1337 void *dump_bitmap_buf; 1338 size_t num_dumpable; 1339 GuestPhysBlock *block_iter = NULL; 1340 size_t bitmap_bufsize = dump_bitmap_get_bufsize(s); 1341 size_t bits_per_buf = bitmap_bufsize * CHAR_BIT; 1342 1343 /* dump_bitmap_buf is used to store dump_bitmap temporarily */ 1344 dump_bitmap_buf = g_malloc0(bitmap_bufsize); 1345 1346 num_dumpable = 0; 1347 last_pfn = 0; 1348 1349 /* 1350 * exam memory page by page, and set the bit in dump_bitmap corresponded 1351 * to the existing page. 1352 */ 1353 while (get_next_page(&block_iter, &pfn, NULL, s)) { 1354 ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s); 1355 if (ret < 0) { 1356 error_setg(errp, "dump: failed to set dump_bitmap"); 1357 goto out; 1358 } 1359 1360 last_pfn = pfn; 1361 num_dumpable++; 1362 } 1363 1364 /* 1365 * set_dump_bitmap will always leave the recently set bit un-sync. Here we 1366 * set the remaining bits from last_pfn to the end of the bitmap buffer to 1367 * 0. With those set, the un-sync bit will be synchronized into the vmcore. 1368 */ 1369 if (num_dumpable > 0) { 1370 ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false, 1371 dump_bitmap_buf, s); 1372 if (ret < 0) { 1373 error_setg(errp, "dump: failed to sync dump_bitmap"); 1374 goto out; 1375 } 1376 } 1377 1378 /* number of dumpable pages that will be dumped later */ 1379 s->num_dumpable = num_dumpable; 1380 1381 out: 1382 g_free(dump_bitmap_buf); 1383 } 1384 1385 static void prepare_data_cache(DataCache *data_cache, DumpState *s, 1386 off_t offset) 1387 { 1388 data_cache->fd = s->fd; 1389 data_cache->data_size = 0; 1390 data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s); 1391 data_cache->buf = g_malloc0(data_cache->buf_size); 1392 data_cache->offset = offset; 1393 } 1394 1395 static int write_cache(DataCache *dc, const void *buf, size_t size, 1396 bool flag_sync) 1397 { 1398 /* 1399 * dc->buf_size should not be less than size, otherwise dc will never be 1400 * enough 1401 */ 1402 assert(size <= dc->buf_size); 1403 1404 /* 1405 * if flag_sync is set, synchronize data in dc->buf into vmcore. 1406 * otherwise check if the space is enough for caching data in buf, if not, 1407 * write the data in dc->buf to dc->fd and reset dc->buf 1408 */ 1409 if ((!flag_sync && dc->data_size + size > dc->buf_size) || 1410 (flag_sync && dc->data_size > 0)) { 1411 if (write_buffer(dc->fd, dc->offset, dc->buf, dc->data_size) < 0) { 1412 return -1; 1413 } 1414 1415 dc->offset += dc->data_size; 1416 dc->data_size = 0; 1417 } 1418 1419 if (!flag_sync) { 1420 memcpy(dc->buf + dc->data_size, buf, size); 1421 dc->data_size += size; 1422 } 1423 1424 return 0; 1425 } 1426 1427 static void free_data_cache(DataCache *data_cache) 1428 { 1429 g_free(data_cache->buf); 1430 } 1431 1432 static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress) 1433 { 1434 switch (flag_compress) { 1435 case DUMP_DH_COMPRESSED_ZLIB: 1436 return compressBound(page_size); 1437 1438 case DUMP_DH_COMPRESSED_LZO: 1439 /* 1440 * LZO will expand incompressible data by a little amount. Please check 1441 * the following URL to see the expansion calculation: 1442 * http://www.oberhumer.com/opensource/lzo/lzofaq.php 1443 */ 1444 return page_size + page_size / 16 + 64 + 3; 1445 1446 #ifdef CONFIG_SNAPPY 1447 case DUMP_DH_COMPRESSED_SNAPPY: 1448 return snappy_max_compressed_length(page_size); 1449 #endif 1450 } 1451 return 0; 1452 } 1453 1454 static void write_dump_pages(DumpState *s, Error **errp) 1455 { 1456 int ret = 0; 1457 DataCache page_desc, page_data; 1458 size_t len_buf_out, size_out; 1459 #ifdef CONFIG_LZO 1460 lzo_bytep wrkmem = NULL; 1461 #endif 1462 uint8_t *buf_out = NULL; 1463 off_t offset_desc, offset_data; 1464 PageDescriptor pd, pd_zero; 1465 uint8_t *buf; 1466 GuestPhysBlock *block_iter = NULL; 1467 uint64_t pfn_iter; 1468 g_autofree uint8_t *page = NULL; 1469 1470 /* get offset of page_desc and page_data in dump file */ 1471 offset_desc = s->offset_page; 1472 offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable; 1473 1474 prepare_data_cache(&page_desc, s, offset_desc); 1475 prepare_data_cache(&page_data, s, offset_data); 1476 1477 /* prepare buffer to store compressed data */ 1478 len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress); 1479 assert(len_buf_out != 0); 1480 1481 #ifdef CONFIG_LZO 1482 wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS); 1483 #endif 1484 1485 buf_out = g_malloc(len_buf_out); 1486 1487 /* 1488 * init zero page's page_desc and page_data, because every zero page 1489 * uses the same page_data 1490 */ 1491 pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size); 1492 pd_zero.flags = cpu_to_dump32(s, 0); 1493 pd_zero.offset = cpu_to_dump64(s, offset_data); 1494 pd_zero.page_flags = cpu_to_dump64(s, 0); 1495 buf = g_malloc0(s->dump_info.page_size); 1496 ret = write_cache(&page_data, buf, s->dump_info.page_size, false); 1497 g_free(buf); 1498 if (ret < 0) { 1499 error_setg(errp, "dump: failed to write page data (zero page)"); 1500 goto out; 1501 } 1502 1503 offset_data += s->dump_info.page_size; 1504 page = g_malloc(s->dump_info.page_size); 1505 1506 /* 1507 * dump memory to vmcore page by page. zero page will all be resided in the 1508 * first page of page section 1509 */ 1510 for (buf = page; get_next_page(&block_iter, &pfn_iter, &buf, s); buf = page) { 1511 /* check zero page */ 1512 if (buffer_is_zero(buf, s->dump_info.page_size)) { 1513 ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor), 1514 false); 1515 if (ret < 0) { 1516 error_setg(errp, "dump: failed to write page desc"); 1517 goto out; 1518 } 1519 } else { 1520 /* 1521 * not zero page, then: 1522 * 1. compress the page 1523 * 2. write the compressed page into the cache of page_data 1524 * 3. get page desc of the compressed page and write it into the 1525 * cache of page_desc 1526 * 1527 * only one compression format will be used here, for 1528 * s->flag_compress is set. But when compression fails to work, 1529 * we fall back to save in plaintext. 1530 */ 1531 size_out = len_buf_out; 1532 if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) && 1533 (compress2(buf_out, (uLongf *)&size_out, buf, 1534 s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) && 1535 (size_out < s->dump_info.page_size)) { 1536 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB); 1537 pd.size = cpu_to_dump32(s, size_out); 1538 1539 ret = write_cache(&page_data, buf_out, size_out, false); 1540 if (ret < 0) { 1541 error_setg(errp, "dump: failed to write page data"); 1542 goto out; 1543 } 1544 #ifdef CONFIG_LZO 1545 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) && 1546 (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out, 1547 (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) && 1548 (size_out < s->dump_info.page_size)) { 1549 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO); 1550 pd.size = cpu_to_dump32(s, size_out); 1551 1552 ret = write_cache(&page_data, buf_out, size_out, false); 1553 if (ret < 0) { 1554 error_setg(errp, "dump: failed to write page data"); 1555 goto out; 1556 } 1557 #endif 1558 #ifdef CONFIG_SNAPPY 1559 } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) && 1560 (snappy_compress((char *)buf, s->dump_info.page_size, 1561 (char *)buf_out, &size_out) == SNAPPY_OK) && 1562 (size_out < s->dump_info.page_size)) { 1563 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY); 1564 pd.size = cpu_to_dump32(s, size_out); 1565 1566 ret = write_cache(&page_data, buf_out, size_out, false); 1567 if (ret < 0) { 1568 error_setg(errp, "dump: failed to write page data"); 1569 goto out; 1570 } 1571 #endif 1572 } else { 1573 /* 1574 * fall back to save in plaintext, size_out should be 1575 * assigned the target's page size 1576 */ 1577 pd.flags = cpu_to_dump32(s, 0); 1578 size_out = s->dump_info.page_size; 1579 pd.size = cpu_to_dump32(s, size_out); 1580 1581 ret = write_cache(&page_data, buf, 1582 s->dump_info.page_size, false); 1583 if (ret < 0) { 1584 error_setg(errp, "dump: failed to write page data"); 1585 goto out; 1586 } 1587 } 1588 1589 /* get and write page desc here */ 1590 pd.page_flags = cpu_to_dump64(s, 0); 1591 pd.offset = cpu_to_dump64(s, offset_data); 1592 offset_data += size_out; 1593 1594 ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false); 1595 if (ret < 0) { 1596 error_setg(errp, "dump: failed to write page desc"); 1597 goto out; 1598 } 1599 } 1600 s->written_size += s->dump_info.page_size; 1601 } 1602 1603 ret = write_cache(&page_desc, NULL, 0, true); 1604 if (ret < 0) { 1605 error_setg(errp, "dump: failed to sync cache for page_desc"); 1606 goto out; 1607 } 1608 ret = write_cache(&page_data, NULL, 0, true); 1609 if (ret < 0) { 1610 error_setg(errp, "dump: failed to sync cache for page_data"); 1611 goto out; 1612 } 1613 1614 out: 1615 free_data_cache(&page_desc); 1616 free_data_cache(&page_data); 1617 1618 #ifdef CONFIG_LZO 1619 g_free(wrkmem); 1620 #endif 1621 1622 g_free(buf_out); 1623 } 1624 1625 static void create_kdump_vmcore(DumpState *s, Error **errp) 1626 { 1627 ERRP_GUARD(); 1628 int ret; 1629 1630 /* 1631 * the kdump-compressed format is: 1632 * File offset 1633 * +------------------------------------------+ 0x0 1634 * | main header (struct disk_dump_header) | 1635 * |------------------------------------------+ block 1 1636 * | sub header (struct kdump_sub_header) | 1637 * |------------------------------------------+ block 2 1638 * | 1st-dump_bitmap | 1639 * |------------------------------------------+ block 2 + X blocks 1640 * | 2nd-dump_bitmap | (aligned by block) 1641 * |------------------------------------------+ block 2 + 2 * X blocks 1642 * | page desc for pfn 0 (struct page_desc) | (aligned by block) 1643 * | page desc for pfn 1 (struct page_desc) | 1644 * | : | 1645 * |------------------------------------------| (not aligned by block) 1646 * | page data (pfn 0) | 1647 * | page data (pfn 1) | 1648 * | : | 1649 * +------------------------------------------+ 1650 */ 1651 1652 ret = write_start_flat_header(s->fd); 1653 if (ret < 0) { 1654 error_setg(errp, "dump: failed to write start flat header"); 1655 return; 1656 } 1657 1658 write_dump_header(s, errp); 1659 if (*errp) { 1660 return; 1661 } 1662 1663 write_dump_bitmap(s, errp); 1664 if (*errp) { 1665 return; 1666 } 1667 1668 write_dump_pages(s, errp); 1669 if (*errp) { 1670 return; 1671 } 1672 1673 ret = write_end_flat_header(s->fd); 1674 if (ret < 0) { 1675 error_setg(errp, "dump: failed to write end flat header"); 1676 return; 1677 } 1678 } 1679 1680 static int validate_start_block(DumpState *s) 1681 { 1682 GuestPhysBlock *block; 1683 1684 if (!dump_has_filter(s)) { 1685 return 0; 1686 } 1687 1688 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 1689 /* This block is out of the range */ 1690 if (block->target_start >= s->filter_area_begin + s->filter_area_length || 1691 block->target_end <= s->filter_area_begin) { 1692 continue; 1693 } 1694 return 0; 1695 } 1696 1697 return -1; 1698 } 1699 1700 static void get_max_mapnr(DumpState *s) 1701 { 1702 GuestPhysBlock *last_block; 1703 1704 last_block = QTAILQ_LAST(&s->guest_phys_blocks.head); 1705 s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end); 1706 } 1707 1708 static DumpState dump_state_global = { .status = DUMP_STATUS_NONE }; 1709 1710 static void dump_state_prepare(DumpState *s) 1711 { 1712 /* zero the struct, setting status to active */ 1713 *s = (DumpState) { .status = DUMP_STATUS_ACTIVE }; 1714 } 1715 1716 bool qemu_system_dump_in_progress(void) 1717 { 1718 DumpState *state = &dump_state_global; 1719 return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE); 1720 } 1721 1722 /* 1723 * calculate total size of memory to be dumped (taking filter into 1724 * account.) 1725 */ 1726 static int64_t dump_calculate_size(DumpState *s) 1727 { 1728 GuestPhysBlock *block; 1729 int64_t total = 0; 1730 1731 QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) { 1732 total += dump_filtered_memblock_size(block, 1733 s->filter_area_begin, 1734 s->filter_area_length); 1735 } 1736 1737 return total; 1738 } 1739 1740 static void vmcoreinfo_update_phys_base(DumpState *s) 1741 { 1742 uint64_t size, note_head_size, name_size, phys_base; 1743 char **lines; 1744 uint8_t *vmci; 1745 size_t i; 1746 1747 if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) { 1748 return; 1749 } 1750 1751 get_note_sizes(s, s->guest_note, ¬e_head_size, &name_size, &size); 1752 note_head_size = ROUND_UP(note_head_size, 4); 1753 1754 vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4); 1755 *(vmci + size) = '\0'; 1756 1757 lines = g_strsplit((char *)vmci, "\n", -1); 1758 for (i = 0; lines[i]; i++) { 1759 const char *prefix = NULL; 1760 1761 if (s->dump_info.d_machine == EM_X86_64) { 1762 prefix = "NUMBER(phys_base)="; 1763 } else if (s->dump_info.d_machine == EM_AARCH64) { 1764 prefix = "NUMBER(PHYS_OFFSET)="; 1765 } 1766 1767 if (prefix && g_str_has_prefix(lines[i], prefix)) { 1768 if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16, 1769 &phys_base) < 0) { 1770 warn_report("Failed to read %s", prefix); 1771 } else { 1772 s->dump_info.phys_base = phys_base; 1773 } 1774 break; 1775 } 1776 } 1777 1778 g_strfreev(lines); 1779 } 1780 1781 static void dump_init(DumpState *s, int fd, bool has_format, 1782 DumpGuestMemoryFormat format, bool paging, bool has_filter, 1783 int64_t begin, int64_t length, Error **errp) 1784 { 1785 ERRP_GUARD(); 1786 VMCoreInfoState *vmci = vmcoreinfo_find(); 1787 CPUState *cpu; 1788 int nr_cpus; 1789 int ret; 1790 1791 s->has_format = has_format; 1792 s->format = format; 1793 s->written_size = 0; 1794 1795 /* kdump-compressed is conflict with paging and filter */ 1796 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1797 assert(!paging && !has_filter); 1798 } 1799 1800 if (runstate_is_running()) { 1801 vm_stop(RUN_STATE_SAVE_VM); 1802 s->resume = true; 1803 } else { 1804 s->resume = false; 1805 } 1806 1807 /* If we use KVM, we should synchronize the registers before we get dump 1808 * info or physmap info. 1809 */ 1810 cpu_synchronize_all_states(); 1811 nr_cpus = 0; 1812 CPU_FOREACH(cpu) { 1813 nr_cpus++; 1814 } 1815 1816 s->fd = fd; 1817 if (has_filter && !length) { 1818 error_setg(errp, QERR_INVALID_PARAMETER, "length"); 1819 goto cleanup; 1820 } 1821 s->filter_area_begin = begin; 1822 s->filter_area_length = length; 1823 1824 /* First index is 0, it's the special null name */ 1825 s->string_table_buf = g_array_new(FALSE, TRUE, 1); 1826 /* 1827 * Allocate the null name, due to the clearing option set to true 1828 * it will be 0. 1829 */ 1830 g_array_set_size(s->string_table_buf, 1); 1831 1832 memory_mapping_list_init(&s->list); 1833 1834 guest_phys_blocks_init(&s->guest_phys_blocks); 1835 guest_phys_blocks_append(&s->guest_phys_blocks); 1836 s->total_size = dump_calculate_size(s); 1837 #ifdef DEBUG_DUMP_GUEST_MEMORY 1838 fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size); 1839 #endif 1840 1841 /* it does not make sense to dump non-existent memory */ 1842 if (!s->total_size) { 1843 error_setg(errp, "dump: no guest memory to dump"); 1844 goto cleanup; 1845 } 1846 1847 /* Is the filter filtering everything? */ 1848 if (validate_start_block(s) == -1) { 1849 error_setg(errp, QERR_INVALID_PARAMETER, "begin"); 1850 goto cleanup; 1851 } 1852 1853 /* get dump info: endian, class and architecture. 1854 * If the target architecture is not supported, cpu_get_dump_info() will 1855 * return -1. 1856 */ 1857 ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks); 1858 if (ret < 0) { 1859 error_setg(errp, QERR_UNSUPPORTED); 1860 goto cleanup; 1861 } 1862 1863 if (!s->dump_info.page_size) { 1864 s->dump_info.page_size = TARGET_PAGE_SIZE; 1865 } 1866 1867 s->note_size = cpu_get_note_size(s->dump_info.d_class, 1868 s->dump_info.d_machine, nr_cpus); 1869 if (s->note_size < 0) { 1870 error_setg(errp, QERR_UNSUPPORTED); 1871 goto cleanup; 1872 } 1873 1874 /* 1875 * The goal of this block is to (a) update the previously guessed 1876 * phys_base, (b) copy the guest note out of the guest. 1877 * Failure to do so is not fatal for dumping. 1878 */ 1879 if (vmci) { 1880 uint64_t addr, note_head_size, name_size, desc_size; 1881 uint32_t size; 1882 uint16_t format; 1883 1884 note_head_size = dump_is_64bit(s) ? 1885 sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr); 1886 1887 format = le16_to_cpu(vmci->vmcoreinfo.guest_format); 1888 size = le32_to_cpu(vmci->vmcoreinfo.size); 1889 addr = le64_to_cpu(vmci->vmcoreinfo.paddr); 1890 if (!vmci->has_vmcoreinfo) { 1891 warn_report("guest note is not present"); 1892 } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) { 1893 warn_report("guest note size is invalid: %" PRIu32, size); 1894 } else if (format != FW_CFG_VMCOREINFO_FORMAT_ELF) { 1895 warn_report("guest note format is unsupported: %" PRIu16, format); 1896 } else { 1897 s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */ 1898 cpu_physical_memory_read(addr, s->guest_note, size); 1899 1900 get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size); 1901 s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size, 1902 desc_size); 1903 if (name_size > MAX_GUEST_NOTE_SIZE || 1904 desc_size > MAX_GUEST_NOTE_SIZE || 1905 s->guest_note_size > size) { 1906 warn_report("Invalid guest note header"); 1907 g_free(s->guest_note); 1908 s->guest_note = NULL; 1909 } else { 1910 vmcoreinfo_update_phys_base(s); 1911 s->note_size += s->guest_note_size; 1912 } 1913 } 1914 } 1915 1916 /* get memory mapping */ 1917 if (paging) { 1918 qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, errp); 1919 if (*errp) { 1920 goto cleanup; 1921 } 1922 } else { 1923 qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks); 1924 } 1925 1926 s->nr_cpus = nr_cpus; 1927 1928 get_max_mapnr(s); 1929 1930 uint64_t tmp; 1931 tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), 1932 s->dump_info.page_size); 1933 s->len_dump_bitmap = tmp * s->dump_info.page_size; 1934 1935 /* init for kdump-compressed format */ 1936 if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 1937 switch (format) { 1938 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB: 1939 s->flag_compress = DUMP_DH_COMPRESSED_ZLIB; 1940 break; 1941 1942 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO: 1943 #ifdef CONFIG_LZO 1944 if (lzo_init() != LZO_E_OK) { 1945 error_setg(errp, "failed to initialize the LZO library"); 1946 goto cleanup; 1947 } 1948 #endif 1949 s->flag_compress = DUMP_DH_COMPRESSED_LZO; 1950 break; 1951 1952 case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY: 1953 s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY; 1954 break; 1955 1956 default: 1957 s->flag_compress = 0; 1958 } 1959 1960 return; 1961 } 1962 1963 if (dump_has_filter(s)) { 1964 memory_mapping_filter(&s->list, s->filter_area_begin, s->filter_area_length); 1965 } 1966 1967 /* 1968 * The first section header is always a special one in which most 1969 * fields are 0. The section header string table is also always 1970 * set. 1971 */ 1972 s->shdr_num = 2; 1973 1974 /* 1975 * Adds the number of architecture sections to shdr_num and sets 1976 * elf_section_data_size so we know the offsets and sizes of all 1977 * parts. 1978 */ 1979 if (s->dump_info.arch_sections_add_fn) { 1980 s->dump_info.arch_sections_add_fn(s); 1981 } 1982 1983 /* 1984 * calculate shdr_num so we know the offsets and sizes of all 1985 * parts. 1986 * Calculate phdr_num 1987 * 1988 * The absolute maximum amount of phdrs is UINT32_MAX - 1 as 1989 * sh_info is 32 bit. There's special handling once we go over 1990 * UINT16_MAX - 1 but that is handled in the ehdr and section 1991 * code. 1992 */ 1993 s->phdr_num = 1; /* Reserve PT_NOTE */ 1994 if (s->list.num <= UINT32_MAX - 1) { 1995 s->phdr_num += s->list.num; 1996 } else { 1997 s->phdr_num = UINT32_MAX; 1998 } 1999 2000 /* 2001 * Now that the number of section and program headers is known we 2002 * can calculate the offsets of the headers and data. 2003 */ 2004 if (dump_is_64bit(s)) { 2005 s->shdr_offset = sizeof(Elf64_Ehdr); 2006 s->phdr_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; 2007 s->note_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; 2008 } else { 2009 s->shdr_offset = sizeof(Elf32_Ehdr); 2010 s->phdr_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; 2011 s->note_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; 2012 } 2013 s->memory_offset = s->note_offset + s->note_size; 2014 s->section_offset = s->memory_offset + s->total_size; 2015 2016 return; 2017 2018 cleanup: 2019 dump_cleanup(s); 2020 } 2021 2022 /* this operation might be time consuming. */ 2023 static void dump_process(DumpState *s, Error **errp) 2024 { 2025 ERRP_GUARD(); 2026 DumpQueryResult *result = NULL; 2027 2028 if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { 2029 #ifdef TARGET_X86_64 2030 create_win_dump(s, errp); 2031 #endif 2032 } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) { 2033 create_kdump_vmcore(s, errp); 2034 } else { 2035 create_vmcore(s, errp); 2036 } 2037 2038 /* make sure status is written after written_size updates */ 2039 smp_wmb(); 2040 qatomic_set(&s->status, 2041 (*errp ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED)); 2042 2043 /* send DUMP_COMPLETED message (unconditionally) */ 2044 result = qmp_query_dump(NULL); 2045 /* should never fail */ 2046 assert(result); 2047 qapi_event_send_dump_completed(result, 2048 *errp ? error_get_pretty(*errp) : NULL); 2049 qapi_free_DumpQueryResult(result); 2050 2051 dump_cleanup(s); 2052 } 2053 2054 static void *dump_thread(void *data) 2055 { 2056 DumpState *s = (DumpState *)data; 2057 dump_process(s, NULL); 2058 return NULL; 2059 } 2060 2061 DumpQueryResult *qmp_query_dump(Error **errp) 2062 { 2063 DumpQueryResult *result = g_new(DumpQueryResult, 1); 2064 DumpState *state = &dump_state_global; 2065 result->status = qatomic_read(&state->status); 2066 /* make sure we are reading status and written_size in order */ 2067 smp_rmb(); 2068 result->completed = state->written_size; 2069 result->total = state->total_size; 2070 return result; 2071 } 2072 2073 void qmp_dump_guest_memory(bool paging, const char *file, 2074 bool has_detach, bool detach, 2075 bool has_begin, int64_t begin, bool has_length, 2076 int64_t length, bool has_format, 2077 DumpGuestMemoryFormat format, Error **errp) 2078 { 2079 ERRP_GUARD(); 2080 const char *p; 2081 int fd = -1; 2082 DumpState *s; 2083 bool detach_p = false; 2084 2085 if (runstate_check(RUN_STATE_INMIGRATE)) { 2086 error_setg(errp, "Dump not allowed during incoming migration."); 2087 return; 2088 } 2089 2090 /* if there is a dump in background, we should wait until the dump 2091 * finished */ 2092 if (qemu_system_dump_in_progress()) { 2093 error_setg(errp, "There is a dump in process, please wait."); 2094 return; 2095 } 2096 2097 /* 2098 * kdump-compressed format need the whole memory dumped, so paging or 2099 * filter is not supported here. 2100 */ 2101 if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) && 2102 (paging || has_begin || has_length)) { 2103 error_setg(errp, "kdump-compressed format doesn't support paging or " 2104 "filter"); 2105 return; 2106 } 2107 if (has_begin && !has_length) { 2108 error_setg(errp, QERR_MISSING_PARAMETER, "length"); 2109 return; 2110 } 2111 if (!has_begin && has_length) { 2112 error_setg(errp, QERR_MISSING_PARAMETER, "begin"); 2113 return; 2114 } 2115 if (has_detach) { 2116 detach_p = detach; 2117 } 2118 2119 /* check whether lzo/snappy is supported */ 2120 #ifndef CONFIG_LZO 2121 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) { 2122 error_setg(errp, "kdump-lzo is not available now"); 2123 return; 2124 } 2125 #endif 2126 2127 #ifndef CONFIG_SNAPPY 2128 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) { 2129 error_setg(errp, "kdump-snappy is not available now"); 2130 return; 2131 } 2132 #endif 2133 2134 #ifndef TARGET_X86_64 2135 if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) { 2136 error_setg(errp, "Windows dump is only available for x86-64"); 2137 return; 2138 } 2139 #endif 2140 2141 #if !defined(WIN32) 2142 if (strstart(file, "fd:", &p)) { 2143 fd = monitor_get_fd(monitor_cur(), p, errp); 2144 if (fd == -1) { 2145 return; 2146 } 2147 } 2148 #endif 2149 2150 if (strstart(file, "file:", &p)) { 2151 fd = qemu_open_old(p, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR); 2152 if (fd < 0) { 2153 error_setg_file_open(errp, errno, p); 2154 return; 2155 } 2156 } 2157 2158 if (fd == -1) { 2159 error_setg(errp, QERR_INVALID_PARAMETER, "protocol"); 2160 return; 2161 } 2162 2163 if (!dump_migration_blocker) { 2164 error_setg(&dump_migration_blocker, 2165 "Live migration disabled: dump-guest-memory in progress"); 2166 } 2167 2168 /* 2169 * Allows even for -only-migratable, but forbid migration during the 2170 * process of dump guest memory. 2171 */ 2172 if (migrate_add_blocker_internal(dump_migration_blocker, errp)) { 2173 /* Remember to release the fd before passing it over to dump state */ 2174 close(fd); 2175 return; 2176 } 2177 2178 s = &dump_state_global; 2179 dump_state_prepare(s); 2180 2181 dump_init(s, fd, has_format, format, paging, has_begin, 2182 begin, length, errp); 2183 if (*errp) { 2184 qatomic_set(&s->status, DUMP_STATUS_FAILED); 2185 return; 2186 } 2187 2188 if (detach_p) { 2189 /* detached dump */ 2190 s->detached = true; 2191 qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread, 2192 s, QEMU_THREAD_DETACHED); 2193 } else { 2194 /* sync dump */ 2195 dump_process(s, errp); 2196 } 2197 } 2198 2199 DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp) 2200 { 2201 DumpGuestMemoryCapability *cap = 2202 g_new0(DumpGuestMemoryCapability, 1); 2203 DumpGuestMemoryFormatList **tail = &cap->formats; 2204 2205 /* elf is always available */ 2206 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF); 2207 2208 /* kdump-zlib is always available */ 2209 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB); 2210 2211 /* add new item if kdump-lzo is available */ 2212 #ifdef CONFIG_LZO 2213 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO); 2214 #endif 2215 2216 /* add new item if kdump-snappy is available */ 2217 #ifdef CONFIG_SNAPPY 2218 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY); 2219 #endif 2220 2221 /* Windows dump is available only if target is x86_64 */ 2222 #ifdef TARGET_X86_64 2223 QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP); 2224 #endif 2225 2226 return cap; 2227 } 2228