xref: /openbmc/qemu/dump/dump.c (revision 56c39a41adadfc567e1ac22089670bfde6b35365)
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(int fd)
813  {
814      MakedumpfileHeader *mh;
815      int ret = 0;
816  
817      QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER);
818      mh = g_malloc0(MAX_SIZE_MDF_HEADER);
819  
820      memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE,
821             MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE));
822  
823      mh->type = cpu_to_be64(TYPE_FLAT_HEADER);
824      mh->version = cpu_to_be64(VERSION_FLAT_HEADER);
825  
826      size_t written_size;
827      written_size = qemu_write_full(fd, mh, MAX_SIZE_MDF_HEADER);
828      if (written_size != MAX_SIZE_MDF_HEADER) {
829          ret = -1;
830      }
831  
832      g_free(mh);
833      return ret;
834  }
835  
836  static int write_end_flat_header(int fd)
837  {
838      MakedumpfileDataHeader mdh;
839  
840      mdh.offset = END_FLAG_FLAT_HEADER;
841      mdh.buf_size = END_FLAG_FLAT_HEADER;
842  
843      size_t written_size;
844      written_size = qemu_write_full(fd, &mdh, sizeof(mdh));
845      if (written_size != sizeof(mdh)) {
846          return -1;
847      }
848  
849      return 0;
850  }
851  
852  static int write_buffer(int fd, off_t offset, const void *buf, size_t size)
853  {
854      size_t written_size;
855      MakedumpfileDataHeader mdh;
856  
857      mdh.offset = cpu_to_be64(offset);
858      mdh.buf_size = cpu_to_be64(size);
859  
860      written_size = qemu_write_full(fd, &mdh, sizeof(mdh));
861      if (written_size != sizeof(mdh)) {
862          return -1;
863      }
864  
865      written_size = qemu_write_full(fd, buf, size);
866      if (written_size != size) {
867          return -1;
868      }
869  
870      return 0;
871  }
872  
873  static int buf_write_note(const void *buf, size_t size, void *opaque)
874  {
875      DumpState *s = opaque;
876  
877      /* note_buf is not enough */
878      if (s->note_buf_offset + size > s->note_size) {
879          return -1;
880      }
881  
882      memcpy(s->note_buf + s->note_buf_offset, buf, size);
883  
884      s->note_buf_offset += size;
885  
886      return 0;
887  }
888  
889  /*
890   * This function retrieves various sizes from an elf header.
891   *
892   * @note has to be a valid ELF note. The return sizes are unmodified
893   * (not padded or rounded up to be multiple of 4).
894   */
895  static void get_note_sizes(DumpState *s, const void *note,
896                             uint64_t *note_head_size,
897                             uint64_t *name_size,
898                             uint64_t *desc_size)
899  {
900      uint64_t note_head_sz;
901      uint64_t name_sz;
902      uint64_t desc_sz;
903  
904      if (dump_is_64bit(s)) {
905          const Elf64_Nhdr *hdr = note;
906          note_head_sz = sizeof(Elf64_Nhdr);
907          name_sz = cpu_to_dump64(s, hdr->n_namesz);
908          desc_sz = cpu_to_dump64(s, hdr->n_descsz);
909      } else {
910          const Elf32_Nhdr *hdr = note;
911          note_head_sz = sizeof(Elf32_Nhdr);
912          name_sz = cpu_to_dump32(s, hdr->n_namesz);
913          desc_sz = cpu_to_dump32(s, hdr->n_descsz);
914      }
915  
916      if (note_head_size) {
917          *note_head_size = note_head_sz;
918      }
919      if (name_size) {
920          *name_size = name_sz;
921      }
922      if (desc_size) {
923          *desc_size = desc_sz;
924      }
925  }
926  
927  static bool note_name_equal(DumpState *s,
928                              const uint8_t *note, const char *name)
929  {
930      int len = strlen(name) + 1;
931      uint64_t head_size, name_size;
932  
933      get_note_sizes(s, note, &head_size, &name_size, NULL);
934      head_size = ROUND_UP(head_size, 4);
935  
936      return name_size == len && memcmp(note + head_size, name, len) == 0;
937  }
938  
939  /* write common header, sub header and elf note to vmcore */
940  static void create_header32(DumpState *s, Error **errp)
941  {
942      ERRP_GUARD();
943      DiskDumpHeader32 *dh = NULL;
944      KdumpSubHeader32 *kh = NULL;
945      size_t size;
946      uint32_t block_size;
947      uint32_t sub_hdr_size;
948      uint32_t bitmap_blocks;
949      uint32_t status = 0;
950      uint64_t offset_note;
951  
952      /* write common header, the version of kdump-compressed format is 6th */
953      size = sizeof(DiskDumpHeader32);
954      dh = g_malloc0(size);
955  
956      memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN);
957      dh->header_version = cpu_to_dump32(s, 6);
958      block_size = s->dump_info.page_size;
959      dh->block_size = cpu_to_dump32(s, block_size);
960      sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size;
961      sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
962      dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size);
963      /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */
964      dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX));
965      dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus);
966      bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2;
967      dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks);
968      strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine));
969  
970      if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) {
971          status |= DUMP_DH_COMPRESSED_ZLIB;
972      }
973  #ifdef CONFIG_LZO
974      if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) {
975          status |= DUMP_DH_COMPRESSED_LZO;
976      }
977  #endif
978  #ifdef CONFIG_SNAPPY
979      if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) {
980          status |= DUMP_DH_COMPRESSED_SNAPPY;
981      }
982  #endif
983      dh->status = cpu_to_dump32(s, status);
984  
985      if (write_buffer(s->fd, 0, dh, size) < 0) {
986          error_setg(errp, "dump: failed to write disk dump header");
987          goto out;
988      }
989  
990      /* write sub header */
991      size = sizeof(KdumpSubHeader32);
992      kh = g_malloc0(size);
993  
994      /* 64bit max_mapnr_64 */
995      kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr);
996      kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base);
997      kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
998  
999      offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
1000      if (s->guest_note &&
1001          note_name_equal(s, s->guest_note, "VMCOREINFO")) {
1002          uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo;
1003  
1004          get_note_sizes(s, s->guest_note,
1005                         &hsize, &name_size, &size_vmcoreinfo_desc);
1006          offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size +
1007              (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
1008          kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
1009          kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc);
1010      }
1011  
1012      kh->offset_note = cpu_to_dump64(s, offset_note);
1013      kh->note_size = cpu_to_dump32(s, s->note_size);
1014  
1015      if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS *
1016                       block_size, kh, size) < 0) {
1017          error_setg(errp, "dump: failed to write kdump sub header");
1018          goto out;
1019      }
1020  
1021      /* write note */
1022      s->note_buf = g_malloc0(s->note_size);
1023      s->note_buf_offset = 0;
1024  
1025      /* use s->note_buf to store notes temporarily */
1026      write_elf32_notes(buf_write_note, s, errp);
1027      if (*errp) {
1028          goto out;
1029      }
1030      if (write_buffer(s->fd, offset_note, s->note_buf,
1031                       s->note_size) < 0) {
1032          error_setg(errp, "dump: failed to write notes");
1033          goto out;
1034      }
1035  
1036      /* get offset of dump_bitmap */
1037      s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) *
1038                               block_size;
1039  
1040      /* get offset of page */
1041      s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) *
1042                       block_size;
1043  
1044  out:
1045      g_free(dh);
1046      g_free(kh);
1047      g_free(s->note_buf);
1048  }
1049  
1050  /* write common header, sub header and elf note to vmcore */
1051  static void create_header64(DumpState *s, Error **errp)
1052  {
1053      ERRP_GUARD();
1054      DiskDumpHeader64 *dh = NULL;
1055      KdumpSubHeader64 *kh = NULL;
1056      size_t size;
1057      uint32_t block_size;
1058      uint32_t sub_hdr_size;
1059      uint32_t bitmap_blocks;
1060      uint32_t status = 0;
1061      uint64_t offset_note;
1062  
1063      /* write common header, the version of kdump-compressed format is 6th */
1064      size = sizeof(DiskDumpHeader64);
1065      dh = g_malloc0(size);
1066  
1067      memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN);
1068      dh->header_version = cpu_to_dump32(s, 6);
1069      block_size = s->dump_info.page_size;
1070      dh->block_size = cpu_to_dump32(s, block_size);
1071      sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size;
1072      sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
1073      dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size);
1074      /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */
1075      dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX));
1076      dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus);
1077      bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2;
1078      dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks);
1079      strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine));
1080  
1081      if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) {
1082          status |= DUMP_DH_COMPRESSED_ZLIB;
1083      }
1084  #ifdef CONFIG_LZO
1085      if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) {
1086          status |= DUMP_DH_COMPRESSED_LZO;
1087      }
1088  #endif
1089  #ifdef CONFIG_SNAPPY
1090      if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) {
1091          status |= DUMP_DH_COMPRESSED_SNAPPY;
1092      }
1093  #endif
1094      dh->status = cpu_to_dump32(s, status);
1095  
1096      if (write_buffer(s->fd, 0, dh, size) < 0) {
1097          error_setg(errp, "dump: failed to write disk dump header");
1098          goto out;
1099      }
1100  
1101      /* write sub header */
1102      size = sizeof(KdumpSubHeader64);
1103      kh = g_malloc0(size);
1104  
1105      /* 64bit max_mapnr_64 */
1106      kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr);
1107      kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base);
1108      kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
1109  
1110      offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
1111      if (s->guest_note &&
1112          note_name_equal(s, s->guest_note, "VMCOREINFO")) {
1113          uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo;
1114  
1115          get_note_sizes(s, s->guest_note,
1116                         &hsize, &name_size, &size_vmcoreinfo_desc);
1117          offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size +
1118              (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
1119          kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
1120          kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc);
1121      }
1122  
1123      kh->offset_note = cpu_to_dump64(s, offset_note);
1124      kh->note_size = cpu_to_dump64(s, s->note_size);
1125  
1126      if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS *
1127                       block_size, kh, size) < 0) {
1128          error_setg(errp, "dump: failed to write kdump sub header");
1129          goto out;
1130      }
1131  
1132      /* write note */
1133      s->note_buf = g_malloc0(s->note_size);
1134      s->note_buf_offset = 0;
1135  
1136      /* use s->note_buf to store notes temporarily */
1137      write_elf64_notes(buf_write_note, s, errp);
1138      if (*errp) {
1139          goto out;
1140      }
1141  
1142      if (write_buffer(s->fd, offset_note, s->note_buf,
1143                       s->note_size) < 0) {
1144          error_setg(errp, "dump: failed to write notes");
1145          goto out;
1146      }
1147  
1148      /* get offset of dump_bitmap */
1149      s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) *
1150                               block_size;
1151  
1152      /* get offset of page */
1153      s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) *
1154                       block_size;
1155  
1156  out:
1157      g_free(dh);
1158      g_free(kh);
1159      g_free(s->note_buf);
1160  }
1161  
1162  static void write_dump_header(DumpState *s, Error **errp)
1163  {
1164      if (dump_is_64bit(s)) {
1165          create_header64(s, errp);
1166      } else {
1167          create_header32(s, errp);
1168      }
1169  }
1170  
1171  static size_t dump_bitmap_get_bufsize(DumpState *s)
1172  {
1173      return s->dump_info.page_size;
1174  }
1175  
1176  /*
1177   * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be
1178   * rewritten, so if need to set the first bit, set last_pfn and pfn to 0.
1179   * set_dump_bitmap will always leave the recently set bit un-sync. And setting
1180   * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into
1181   * vmcore, ie. synchronizing un-sync bit into vmcore.
1182   */
1183  static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value,
1184                             uint8_t *buf, DumpState *s)
1185  {
1186      off_t old_offset, new_offset;
1187      off_t offset_bitmap1, offset_bitmap2;
1188      uint32_t byte, bit;
1189      size_t bitmap_bufsize = dump_bitmap_get_bufsize(s);
1190      size_t bits_per_buf = bitmap_bufsize * CHAR_BIT;
1191  
1192      /* should not set the previous place */
1193      assert(last_pfn <= pfn);
1194  
1195      /*
1196       * if the bit needed to be set is not cached in buf, flush the data in buf
1197       * to vmcore firstly.
1198       * making new_offset be bigger than old_offset can also sync remained data
1199       * into vmcore.
1200       */
1201      old_offset = bitmap_bufsize * (last_pfn / bits_per_buf);
1202      new_offset = bitmap_bufsize * (pfn / bits_per_buf);
1203  
1204      while (old_offset < new_offset) {
1205          /* calculate the offset and write dump_bitmap */
1206          offset_bitmap1 = s->offset_dump_bitmap + old_offset;
1207          if (write_buffer(s->fd, offset_bitmap1, buf,
1208                           bitmap_bufsize) < 0) {
1209              return -1;
1210          }
1211  
1212          /* dump level 1 is chosen, so 1st and 2nd bitmap are same */
1213          offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap +
1214                           old_offset;
1215          if (write_buffer(s->fd, offset_bitmap2, buf,
1216                           bitmap_bufsize) < 0) {
1217              return -1;
1218          }
1219  
1220          memset(buf, 0, bitmap_bufsize);
1221          old_offset += bitmap_bufsize;
1222      }
1223  
1224      /* get the exact place of the bit in the buf, and set it */
1225      byte = (pfn % bits_per_buf) / CHAR_BIT;
1226      bit = (pfn % bits_per_buf) % CHAR_BIT;
1227      if (value) {
1228          buf[byte] |= 1u << bit;
1229      } else {
1230          buf[byte] &= ~(1u << bit);
1231      }
1232  
1233      return 0;
1234  }
1235  
1236  static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr)
1237  {
1238      int target_page_shift = ctz32(s->dump_info.page_size);
1239  
1240      return (addr >> target_page_shift) - ARCH_PFN_OFFSET;
1241  }
1242  
1243  static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn)
1244  {
1245      int target_page_shift = ctz32(s->dump_info.page_size);
1246  
1247      return (pfn + ARCH_PFN_OFFSET) << target_page_shift;
1248  }
1249  
1250  /*
1251   * Return the page frame number and the page content in *bufptr. bufptr can be
1252   * NULL. If not NULL, *bufptr must contains a target page size of pre-allocated
1253   * memory. This is not necessarily the memory returned.
1254   */
1255  static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
1256                            uint8_t **bufptr, DumpState *s)
1257  {
1258      GuestPhysBlock *block = *blockptr;
1259      uint32_t page_size = s->dump_info.page_size;
1260      uint8_t *buf = NULL, *hbuf;
1261      hwaddr addr;
1262  
1263      /* block == NULL means the start of the iteration */
1264      if (!block) {
1265          block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
1266          *blockptr = block;
1267          addr = block->target_start;
1268          *pfnptr = dump_paddr_to_pfn(s, addr);
1269      } else {
1270          *pfnptr += 1;
1271          addr = dump_pfn_to_paddr(s, *pfnptr);
1272      }
1273      assert(block != NULL);
1274  
1275      while (1) {
1276          if (addr >= block->target_start && addr < block->target_end) {
1277              size_t n = MIN(block->target_end - addr, page_size - addr % page_size);
1278              hbuf = block->host_addr + (addr - block->target_start);
1279              if (!buf) {
1280                  if (n == page_size) {
1281                      /* this is a whole target page, go for it */
1282                      assert(addr % page_size == 0);
1283                      buf = hbuf;
1284                      break;
1285                  } else if (bufptr) {
1286                      assert(*bufptr);
1287                      buf = *bufptr;
1288                      memset(buf, 0, page_size);
1289                  } else {
1290                      return true;
1291                  }
1292              }
1293  
1294              memcpy(buf + addr % page_size, hbuf, n);
1295              addr += n;
1296              if (addr % page_size == 0 || addr >= block->target_end) {
1297                  /* we filled up the page or the current block is finished */
1298                  break;
1299              }
1300          } else {
1301              /* the next page is in the next block */
1302              *blockptr = block = QTAILQ_NEXT(block, next);
1303              if (!block) {
1304                  break;
1305              }
1306  
1307              addr = block->target_start;
1308              /* are we still in the same page? */
1309              if (dump_paddr_to_pfn(s, addr) != *pfnptr) {
1310                  if (buf) {
1311                      /* no, but we already filled something earlier, return it */
1312                      break;
1313                  } else {
1314                      /* else continue from there */
1315                      *pfnptr = dump_paddr_to_pfn(s, addr);
1316                  }
1317              }
1318          }
1319      }
1320  
1321      if (bufptr) {
1322          *bufptr = buf;
1323      }
1324  
1325      return buf != NULL;
1326  }
1327  
1328  static void write_dump_bitmap(DumpState *s, Error **errp)
1329  {
1330      int ret = 0;
1331      uint64_t last_pfn, pfn;
1332      void *dump_bitmap_buf;
1333      size_t num_dumpable;
1334      GuestPhysBlock *block_iter = NULL;
1335      size_t bitmap_bufsize = dump_bitmap_get_bufsize(s);
1336      size_t bits_per_buf = bitmap_bufsize * CHAR_BIT;
1337  
1338      /* dump_bitmap_buf is used to store dump_bitmap temporarily */
1339      dump_bitmap_buf = g_malloc0(bitmap_bufsize);
1340  
1341      num_dumpable = 0;
1342      last_pfn = 0;
1343  
1344      /*
1345       * exam memory page by page, and set the bit in dump_bitmap corresponded
1346       * to the existing page.
1347       */
1348      while (get_next_page(&block_iter, &pfn, NULL, s)) {
1349          ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s);
1350          if (ret < 0) {
1351              error_setg(errp, "dump: failed to set dump_bitmap");
1352              goto out;
1353          }
1354  
1355          last_pfn = pfn;
1356          num_dumpable++;
1357      }
1358  
1359      /*
1360       * set_dump_bitmap will always leave the recently set bit un-sync. Here we
1361       * set the remaining bits from last_pfn to the end of the bitmap buffer to
1362       * 0. With those set, the un-sync bit will be synchronized into the vmcore.
1363       */
1364      if (num_dumpable > 0) {
1365          ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false,
1366                                dump_bitmap_buf, s);
1367          if (ret < 0) {
1368              error_setg(errp, "dump: failed to sync dump_bitmap");
1369              goto out;
1370          }
1371      }
1372  
1373      /* number of dumpable pages that will be dumped later */
1374      s->num_dumpable = num_dumpable;
1375  
1376  out:
1377      g_free(dump_bitmap_buf);
1378  }
1379  
1380  static void prepare_data_cache(DataCache *data_cache, DumpState *s,
1381                                 off_t offset)
1382  {
1383      data_cache->fd = s->fd;
1384      data_cache->data_size = 0;
1385      data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s);
1386      data_cache->buf = g_malloc0(data_cache->buf_size);
1387      data_cache->offset = offset;
1388  }
1389  
1390  static int write_cache(DataCache *dc, const void *buf, size_t size,
1391                         bool flag_sync)
1392  {
1393      /*
1394       * dc->buf_size should not be less than size, otherwise dc will never be
1395       * enough
1396       */
1397      assert(size <= dc->buf_size);
1398  
1399      /*
1400       * if flag_sync is set, synchronize data in dc->buf into vmcore.
1401       * otherwise check if the space is enough for caching data in buf, if not,
1402       * write the data in dc->buf to dc->fd and reset dc->buf
1403       */
1404      if ((!flag_sync && dc->data_size + size > dc->buf_size) ||
1405          (flag_sync && dc->data_size > 0)) {
1406          if (write_buffer(dc->fd, dc->offset, dc->buf, dc->data_size) < 0) {
1407              return -1;
1408          }
1409  
1410          dc->offset += dc->data_size;
1411          dc->data_size = 0;
1412      }
1413  
1414      if (!flag_sync) {
1415          memcpy(dc->buf + dc->data_size, buf, size);
1416          dc->data_size += size;
1417      }
1418  
1419      return 0;
1420  }
1421  
1422  static void free_data_cache(DataCache *data_cache)
1423  {
1424      g_free(data_cache->buf);
1425  }
1426  
1427  static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress)
1428  {
1429      switch (flag_compress) {
1430      case DUMP_DH_COMPRESSED_ZLIB:
1431          return compressBound(page_size);
1432  
1433      case DUMP_DH_COMPRESSED_LZO:
1434          /*
1435           * LZO will expand incompressible data by a little amount. Please check
1436           * the following URL to see the expansion calculation:
1437           * http://www.oberhumer.com/opensource/lzo/lzofaq.php
1438           */
1439          return page_size + page_size / 16 + 64 + 3;
1440  
1441  #ifdef CONFIG_SNAPPY
1442      case DUMP_DH_COMPRESSED_SNAPPY:
1443          return snappy_max_compressed_length(page_size);
1444  #endif
1445      }
1446      return 0;
1447  }
1448  
1449  static void write_dump_pages(DumpState *s, Error **errp)
1450  {
1451      int ret = 0;
1452      DataCache page_desc, page_data;
1453      size_t len_buf_out, size_out;
1454  #ifdef CONFIG_LZO
1455      lzo_bytep wrkmem = NULL;
1456  #endif
1457      uint8_t *buf_out = NULL;
1458      off_t offset_desc, offset_data;
1459      PageDescriptor pd, pd_zero;
1460      uint8_t *buf;
1461      GuestPhysBlock *block_iter = NULL;
1462      uint64_t pfn_iter;
1463      g_autofree uint8_t *page = NULL;
1464  
1465      /* get offset of page_desc and page_data in dump file */
1466      offset_desc = s->offset_page;
1467      offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable;
1468  
1469      prepare_data_cache(&page_desc, s, offset_desc);
1470      prepare_data_cache(&page_data, s, offset_data);
1471  
1472      /* prepare buffer to store compressed data */
1473      len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress);
1474      assert(len_buf_out != 0);
1475  
1476  #ifdef CONFIG_LZO
1477      wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS);
1478  #endif
1479  
1480      buf_out = g_malloc(len_buf_out);
1481  
1482      /*
1483       * init zero page's page_desc and page_data, because every zero page
1484       * uses the same page_data
1485       */
1486      pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size);
1487      pd_zero.flags = cpu_to_dump32(s, 0);
1488      pd_zero.offset = cpu_to_dump64(s, offset_data);
1489      pd_zero.page_flags = cpu_to_dump64(s, 0);
1490      buf = g_malloc0(s->dump_info.page_size);
1491      ret = write_cache(&page_data, buf, s->dump_info.page_size, false);
1492      g_free(buf);
1493      if (ret < 0) {
1494          error_setg(errp, "dump: failed to write page data (zero page)");
1495          goto out;
1496      }
1497  
1498      offset_data += s->dump_info.page_size;
1499      page = g_malloc(s->dump_info.page_size);
1500  
1501      /*
1502       * dump memory to vmcore page by page. zero page will all be resided in the
1503       * first page of page section
1504       */
1505      for (buf = page; get_next_page(&block_iter, &pfn_iter, &buf, s); buf = page) {
1506          /* check zero page */
1507          if (buffer_is_zero(buf, s->dump_info.page_size)) {
1508              ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor),
1509                                false);
1510              if (ret < 0) {
1511                  error_setg(errp, "dump: failed to write page desc");
1512                  goto out;
1513              }
1514          } else {
1515              /*
1516               * not zero page, then:
1517               * 1. compress the page
1518               * 2. write the compressed page into the cache of page_data
1519               * 3. get page desc of the compressed page and write it into the
1520               *    cache of page_desc
1521               *
1522               * only one compression format will be used here, for
1523               * s->flag_compress is set. But when compression fails to work,
1524               * we fall back to save in plaintext.
1525               */
1526               size_out = len_buf_out;
1527               if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) &&
1528                      (compress2(buf_out, (uLongf *)&size_out, buf,
1529                                 s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) &&
1530                      (size_out < s->dump_info.page_size)) {
1531                  pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB);
1532                  pd.size  = cpu_to_dump32(s, size_out);
1533  
1534                  ret = write_cache(&page_data, buf_out, size_out, false);
1535                  if (ret < 0) {
1536                      error_setg(errp, "dump: failed to write page data");
1537                      goto out;
1538                  }
1539  #ifdef CONFIG_LZO
1540              } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) &&
1541                      (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out,
1542                      (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) &&
1543                      (size_out < s->dump_info.page_size)) {
1544                  pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO);
1545                  pd.size  = cpu_to_dump32(s, size_out);
1546  
1547                  ret = write_cache(&page_data, buf_out, size_out, false);
1548                  if (ret < 0) {
1549                      error_setg(errp, "dump: failed to write page data");
1550                      goto out;
1551                  }
1552  #endif
1553  #ifdef CONFIG_SNAPPY
1554              } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) &&
1555                      (snappy_compress((char *)buf, s->dump_info.page_size,
1556                      (char *)buf_out, &size_out) == SNAPPY_OK) &&
1557                      (size_out < s->dump_info.page_size)) {
1558                  pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY);
1559                  pd.size  = cpu_to_dump32(s, size_out);
1560  
1561                  ret = write_cache(&page_data, buf_out, size_out, false);
1562                  if (ret < 0) {
1563                      error_setg(errp, "dump: failed to write page data");
1564                      goto out;
1565                  }
1566  #endif
1567              } else {
1568                  /*
1569                   * fall back to save in plaintext, size_out should be
1570                   * assigned the target's page size
1571                   */
1572                  pd.flags = cpu_to_dump32(s, 0);
1573                  size_out = s->dump_info.page_size;
1574                  pd.size = cpu_to_dump32(s, size_out);
1575  
1576                  ret = write_cache(&page_data, buf,
1577                                    s->dump_info.page_size, false);
1578                  if (ret < 0) {
1579                      error_setg(errp, "dump: failed to write page data");
1580                      goto out;
1581                  }
1582              }
1583  
1584              /* get and write page desc here */
1585              pd.page_flags = cpu_to_dump64(s, 0);
1586              pd.offset = cpu_to_dump64(s, offset_data);
1587              offset_data += size_out;
1588  
1589              ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false);
1590              if (ret < 0) {
1591                  error_setg(errp, "dump: failed to write page desc");
1592                  goto out;
1593              }
1594          }
1595          s->written_size += s->dump_info.page_size;
1596      }
1597  
1598      ret = write_cache(&page_desc, NULL, 0, true);
1599      if (ret < 0) {
1600          error_setg(errp, "dump: failed to sync cache for page_desc");
1601          goto out;
1602      }
1603      ret = write_cache(&page_data, NULL, 0, true);
1604      if (ret < 0) {
1605          error_setg(errp, "dump: failed to sync cache for page_data");
1606          goto out;
1607      }
1608  
1609  out:
1610      free_data_cache(&page_desc);
1611      free_data_cache(&page_data);
1612  
1613  #ifdef CONFIG_LZO
1614      g_free(wrkmem);
1615  #endif
1616  
1617      g_free(buf_out);
1618  }
1619  
1620  static void create_kdump_vmcore(DumpState *s, Error **errp)
1621  {
1622      ERRP_GUARD();
1623      int ret;
1624  
1625      /*
1626       * the kdump-compressed format is:
1627       *                                               File offset
1628       *  +------------------------------------------+ 0x0
1629       *  |    main header (struct disk_dump_header) |
1630       *  |------------------------------------------+ block 1
1631       *  |    sub header (struct kdump_sub_header)  |
1632       *  |------------------------------------------+ block 2
1633       *  |            1st-dump_bitmap               |
1634       *  |------------------------------------------+ block 2 + X blocks
1635       *  |            2nd-dump_bitmap               | (aligned by block)
1636       *  |------------------------------------------+ block 2 + 2 * X blocks
1637       *  |  page desc for pfn 0 (struct page_desc)  | (aligned by block)
1638       *  |  page desc for pfn 1 (struct page_desc)  |
1639       *  |                    :                     |
1640       *  |------------------------------------------| (not aligned by block)
1641       *  |         page data (pfn 0)                |
1642       *  |         page data (pfn 1)                |
1643       *  |                    :                     |
1644       *  +------------------------------------------+
1645       */
1646  
1647      ret = write_start_flat_header(s->fd);
1648      if (ret < 0) {
1649          error_setg(errp, "dump: failed to write start flat header");
1650          return;
1651      }
1652  
1653      write_dump_header(s, errp);
1654      if (*errp) {
1655          return;
1656      }
1657  
1658      write_dump_bitmap(s, errp);
1659      if (*errp) {
1660          return;
1661      }
1662  
1663      write_dump_pages(s, errp);
1664      if (*errp) {
1665          return;
1666      }
1667  
1668      ret = write_end_flat_header(s->fd);
1669      if (ret < 0) {
1670          error_setg(errp, "dump: failed to write end flat header");
1671          return;
1672      }
1673  }
1674  
1675  static int validate_start_block(DumpState *s)
1676  {
1677      GuestPhysBlock *block;
1678  
1679      if (!dump_has_filter(s)) {
1680          return 0;
1681      }
1682  
1683      QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
1684          /* This block is out of the range */
1685          if (block->target_start >= s->filter_area_begin + s->filter_area_length ||
1686              block->target_end <= s->filter_area_begin) {
1687              continue;
1688          }
1689          return 0;
1690     }
1691  
1692      return -1;
1693  }
1694  
1695  static void get_max_mapnr(DumpState *s)
1696  {
1697      GuestPhysBlock *last_block;
1698  
1699      last_block = QTAILQ_LAST(&s->guest_phys_blocks.head);
1700      s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end);
1701  }
1702  
1703  static DumpState dump_state_global = { .status = DUMP_STATUS_NONE };
1704  
1705  static void dump_state_prepare(DumpState *s)
1706  {
1707      /* zero the struct, setting status to active */
1708      *s = (DumpState) { .status = DUMP_STATUS_ACTIVE };
1709  }
1710  
1711  bool qemu_system_dump_in_progress(void)
1712  {
1713      DumpState *state = &dump_state_global;
1714      return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE);
1715  }
1716  
1717  /*
1718   * calculate total size of memory to be dumped (taking filter into
1719   * account.)
1720   */
1721  static int64_t dump_calculate_size(DumpState *s)
1722  {
1723      GuestPhysBlock *block;
1724      int64_t total = 0;
1725  
1726      QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
1727          total += dump_filtered_memblock_size(block,
1728                                               s->filter_area_begin,
1729                                               s->filter_area_length);
1730      }
1731  
1732      return total;
1733  }
1734  
1735  static void vmcoreinfo_update_phys_base(DumpState *s)
1736  {
1737      uint64_t size, note_head_size, name_size, phys_base;
1738      char **lines;
1739      uint8_t *vmci;
1740      size_t i;
1741  
1742      if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) {
1743          return;
1744      }
1745  
1746      get_note_sizes(s, s->guest_note, &note_head_size, &name_size, &size);
1747      note_head_size = ROUND_UP(note_head_size, 4);
1748  
1749      vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4);
1750      *(vmci + size) = '\0';
1751  
1752      lines = g_strsplit((char *)vmci, "\n", -1);
1753      for (i = 0; lines[i]; i++) {
1754          const char *prefix = NULL;
1755  
1756          if (s->dump_info.d_machine == EM_X86_64) {
1757              prefix = "NUMBER(phys_base)=";
1758          } else if (s->dump_info.d_machine == EM_AARCH64) {
1759              prefix = "NUMBER(PHYS_OFFSET)=";
1760          }
1761  
1762          if (prefix && g_str_has_prefix(lines[i], prefix)) {
1763              if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16,
1764                                &phys_base) < 0) {
1765                  warn_report("Failed to read %s", prefix);
1766              } else {
1767                  s->dump_info.phys_base = phys_base;
1768              }
1769              break;
1770          }
1771      }
1772  
1773      g_strfreev(lines);
1774  }
1775  
1776  static void dump_init(DumpState *s, int fd, bool has_format,
1777                        DumpGuestMemoryFormat format, bool paging, bool has_filter,
1778                        int64_t begin, int64_t length, Error **errp)
1779  {
1780      ERRP_GUARD();
1781      VMCoreInfoState *vmci = vmcoreinfo_find();
1782      CPUState *cpu;
1783      int nr_cpus;
1784      int ret;
1785  
1786      s->has_format = has_format;
1787      s->format = format;
1788      s->written_size = 0;
1789  
1790      /* kdump-compressed is conflict with paging and filter */
1791      if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
1792          assert(!paging && !has_filter);
1793      }
1794  
1795      if (runstate_is_running()) {
1796          vm_stop(RUN_STATE_SAVE_VM);
1797          s->resume = true;
1798      } else {
1799          s->resume = false;
1800      }
1801  
1802      /* If we use KVM, we should synchronize the registers before we get dump
1803       * info or physmap info.
1804       */
1805      cpu_synchronize_all_states();
1806      nr_cpus = 0;
1807      CPU_FOREACH(cpu) {
1808          nr_cpus++;
1809      }
1810  
1811      s->fd = fd;
1812      if (has_filter && !length) {
1813          error_setg(errp, QERR_INVALID_PARAMETER, "length");
1814          goto cleanup;
1815      }
1816      s->filter_area_begin = begin;
1817      s->filter_area_length = length;
1818  
1819      /* First index is 0, it's the special null name */
1820      s->string_table_buf = g_array_new(FALSE, TRUE, 1);
1821      /*
1822       * Allocate the null name, due to the clearing option set to true
1823       * it will be 0.
1824       */
1825      g_array_set_size(s->string_table_buf, 1);
1826  
1827      memory_mapping_list_init(&s->list);
1828  
1829      guest_phys_blocks_init(&s->guest_phys_blocks);
1830      guest_phys_blocks_append(&s->guest_phys_blocks);
1831      s->total_size = dump_calculate_size(s);
1832  #ifdef DEBUG_DUMP_GUEST_MEMORY
1833      fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size);
1834  #endif
1835  
1836      /* it does not make sense to dump non-existent memory */
1837      if (!s->total_size) {
1838          error_setg(errp, "dump: no guest memory to dump");
1839          goto cleanup;
1840      }
1841  
1842      /* Is the filter filtering everything? */
1843      if (validate_start_block(s) == -1) {
1844          error_setg(errp, QERR_INVALID_PARAMETER, "begin");
1845          goto cleanup;
1846      }
1847  
1848      /* get dump info: endian, class and architecture.
1849       * If the target architecture is not supported, cpu_get_dump_info() will
1850       * return -1.
1851       */
1852      ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks);
1853      if (ret < 0) {
1854          error_setg(errp,
1855                     "dumping guest memory is not supported on this target");
1856          goto cleanup;
1857      }
1858  
1859      if (!s->dump_info.page_size) {
1860          s->dump_info.page_size = qemu_target_page_size();
1861      }
1862  
1863      s->note_size = cpu_get_note_size(s->dump_info.d_class,
1864                                       s->dump_info.d_machine, nr_cpus);
1865      assert(s->note_size >= 0);
1866  
1867      /*
1868       * The goal of this block is to (a) update the previously guessed
1869       * phys_base, (b) copy the guest note out of the guest.
1870       * Failure to do so is not fatal for dumping.
1871       */
1872      if (vmci) {
1873          uint64_t addr, note_head_size, name_size, desc_size;
1874          uint32_t size;
1875          uint16_t format;
1876  
1877          note_head_size = dump_is_64bit(s) ?
1878              sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr);
1879  
1880          format = le16_to_cpu(vmci->vmcoreinfo.guest_format);
1881          size = le32_to_cpu(vmci->vmcoreinfo.size);
1882          addr = le64_to_cpu(vmci->vmcoreinfo.paddr);
1883          if (!vmci->has_vmcoreinfo) {
1884              warn_report("guest note is not present");
1885          } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) {
1886              warn_report("guest note size is invalid: %" PRIu32, size);
1887          } else if (format != FW_CFG_VMCOREINFO_FORMAT_ELF) {
1888              warn_report("guest note format is unsupported: %" PRIu16, format);
1889          } else {
1890              s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */
1891              cpu_physical_memory_read(addr, s->guest_note, size);
1892  
1893              get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size);
1894              s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size,
1895                                                 desc_size);
1896              if (name_size > MAX_GUEST_NOTE_SIZE ||
1897                  desc_size > MAX_GUEST_NOTE_SIZE ||
1898                  s->guest_note_size > size) {
1899                  warn_report("Invalid guest note header");
1900                  g_free(s->guest_note);
1901                  s->guest_note = NULL;
1902              } else {
1903                  vmcoreinfo_update_phys_base(s);
1904                  s->note_size += s->guest_note_size;
1905              }
1906          }
1907      }
1908  
1909      /* get memory mapping */
1910      if (paging) {
1911          qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, errp);
1912          if (*errp) {
1913              goto cleanup;
1914          }
1915      } else {
1916          qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks);
1917      }
1918  
1919      s->nr_cpus = nr_cpus;
1920  
1921      get_max_mapnr(s);
1922  
1923      uint64_t tmp;
1924      tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT),
1925                         s->dump_info.page_size);
1926      s->len_dump_bitmap = tmp * s->dump_info.page_size;
1927  
1928      /* init for kdump-compressed format */
1929      if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
1930          switch (format) {
1931          case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB:
1932              s->flag_compress = DUMP_DH_COMPRESSED_ZLIB;
1933              break;
1934  
1935          case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO:
1936  #ifdef CONFIG_LZO
1937              if (lzo_init() != LZO_E_OK) {
1938                  error_setg(errp, "failed to initialize the LZO library");
1939                  goto cleanup;
1940              }
1941  #endif
1942              s->flag_compress = DUMP_DH_COMPRESSED_LZO;
1943              break;
1944  
1945          case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY:
1946              s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY;
1947              break;
1948  
1949          default:
1950              s->flag_compress = 0;
1951          }
1952  
1953          return;
1954      }
1955  
1956      if (dump_has_filter(s)) {
1957          memory_mapping_filter(&s->list, s->filter_area_begin, s->filter_area_length);
1958      }
1959  
1960      /*
1961       * The first section header is always a special one in which most
1962       * fields are 0. The section header string table is also always
1963       * set.
1964       */
1965      s->shdr_num = 2;
1966  
1967      /*
1968       * Adds the number of architecture sections to shdr_num and sets
1969       * elf_section_data_size so we know the offsets and sizes of all
1970       * parts.
1971       */
1972      if (s->dump_info.arch_sections_add_fn) {
1973          s->dump_info.arch_sections_add_fn(s);
1974      }
1975  
1976      /*
1977       * calculate shdr_num so we know the offsets and sizes of all
1978       * parts.
1979       * Calculate phdr_num
1980       *
1981       * The absolute maximum amount of phdrs is UINT32_MAX - 1 as
1982       * sh_info is 32 bit. There's special handling once we go over
1983       * UINT16_MAX - 1 but that is handled in the ehdr and section
1984       * code.
1985       */
1986      s->phdr_num = 1; /* Reserve PT_NOTE */
1987      if (s->list.num <= UINT32_MAX - 1) {
1988          s->phdr_num += s->list.num;
1989      } else {
1990          s->phdr_num = UINT32_MAX;
1991      }
1992  
1993      /*
1994       * Now that the number of section and program headers is known we
1995       * can calculate the offsets of the headers and data.
1996       */
1997      if (dump_is_64bit(s)) {
1998          s->shdr_offset = sizeof(Elf64_Ehdr);
1999          s->phdr_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num;
2000          s->note_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num;
2001      } else {
2002          s->shdr_offset = sizeof(Elf32_Ehdr);
2003          s->phdr_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num;
2004          s->note_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num;
2005      }
2006      s->memory_offset = s->note_offset + s->note_size;
2007      s->section_offset = s->memory_offset + s->total_size;
2008  
2009      return;
2010  
2011  cleanup:
2012      dump_cleanup(s);
2013  }
2014  
2015  /* this operation might be time consuming. */
2016  static void dump_process(DumpState *s, Error **errp)
2017  {
2018      ERRP_GUARD();
2019      DumpQueryResult *result = NULL;
2020  
2021      if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) {
2022          create_win_dump(s, errp);
2023      } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
2024          create_kdump_vmcore(s, errp);
2025      } else {
2026          create_vmcore(s, errp);
2027      }
2028  
2029      /* make sure status is written after written_size updates */
2030      smp_wmb();
2031      qatomic_set(&s->status,
2032                 (*errp ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED));
2033  
2034      /* send DUMP_COMPLETED message (unconditionally) */
2035      result = qmp_query_dump(NULL);
2036      /* should never fail */
2037      assert(result);
2038      qapi_event_send_dump_completed(result,
2039                                     *errp ? error_get_pretty(*errp) : NULL);
2040      qapi_free_DumpQueryResult(result);
2041  
2042      dump_cleanup(s);
2043  }
2044  
2045  static void *dump_thread(void *data)
2046  {
2047      DumpState *s = (DumpState *)data;
2048      dump_process(s, NULL);
2049      return NULL;
2050  }
2051  
2052  DumpQueryResult *qmp_query_dump(Error **errp)
2053  {
2054      DumpQueryResult *result = g_new(DumpQueryResult, 1);
2055      DumpState *state = &dump_state_global;
2056      result->status = qatomic_read(&state->status);
2057      /* make sure we are reading status and written_size in order */
2058      smp_rmb();
2059      result->completed = state->written_size;
2060      result->total = state->total_size;
2061      return result;
2062  }
2063  
2064  void qmp_dump_guest_memory(bool paging, const char *file,
2065                             bool has_detach, bool detach,
2066                             bool has_begin, int64_t begin, bool has_length,
2067                             int64_t length, bool has_format,
2068                             DumpGuestMemoryFormat format, Error **errp)
2069  {
2070      ERRP_GUARD();
2071      const char *p;
2072      int fd = -1;
2073      DumpState *s;
2074      bool detach_p = false;
2075  
2076      if (runstate_check(RUN_STATE_INMIGRATE)) {
2077          error_setg(errp, "Dump not allowed during incoming migration.");
2078          return;
2079      }
2080  
2081      /* if there is a dump in background, we should wait until the dump
2082       * finished */
2083      if (qemu_system_dump_in_progress()) {
2084          error_setg(errp, "There is a dump in process, please wait.");
2085          return;
2086      }
2087  
2088      /*
2089       * kdump-compressed format need the whole memory dumped, so paging or
2090       * filter is not supported here.
2091       */
2092      if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) &&
2093          (paging || has_begin || has_length)) {
2094          error_setg(errp, "kdump-compressed format doesn't support paging or "
2095                           "filter");
2096          return;
2097      }
2098      if (has_begin && !has_length) {
2099          error_setg(errp, QERR_MISSING_PARAMETER, "length");
2100          return;
2101      }
2102      if (!has_begin && has_length) {
2103          error_setg(errp, QERR_MISSING_PARAMETER, "begin");
2104          return;
2105      }
2106      if (has_detach) {
2107          detach_p = detach;
2108      }
2109  
2110      /* check whether lzo/snappy is supported */
2111  #ifndef CONFIG_LZO
2112      if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) {
2113          error_setg(errp, "kdump-lzo is not available now");
2114          return;
2115      }
2116  #endif
2117  
2118  #ifndef CONFIG_SNAPPY
2119      if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) {
2120          error_setg(errp, "kdump-snappy is not available now");
2121          return;
2122      }
2123  #endif
2124  
2125      if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP
2126          && !win_dump_available(errp)) {
2127          return;
2128      }
2129  
2130  #if !defined(WIN32)
2131      if (strstart(file, "fd:", &p)) {
2132          fd = monitor_get_fd(monitor_cur(), p, errp);
2133          if (fd == -1) {
2134              return;
2135          }
2136      }
2137  #endif
2138  
2139      if  (strstart(file, "file:", &p)) {
2140          fd = qemu_open_old(p, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR);
2141          if (fd < 0) {
2142              error_setg_file_open(errp, errno, p);
2143              return;
2144          }
2145      }
2146  
2147      if (fd == -1) {
2148          error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
2149          return;
2150      }
2151  
2152      if (!dump_migration_blocker) {
2153          error_setg(&dump_migration_blocker,
2154                     "Live migration disabled: dump-guest-memory in progress");
2155      }
2156  
2157      /*
2158       * Allows even for -only-migratable, but forbid migration during the
2159       * process of dump guest memory.
2160       */
2161      if (migrate_add_blocker_internal(dump_migration_blocker, errp)) {
2162          /* Remember to release the fd before passing it over to dump state */
2163          close(fd);
2164          return;
2165      }
2166  
2167      s = &dump_state_global;
2168      dump_state_prepare(s);
2169  
2170      dump_init(s, fd, has_format, format, paging, has_begin,
2171                begin, length, errp);
2172      if (*errp) {
2173          qatomic_set(&s->status, DUMP_STATUS_FAILED);
2174          return;
2175      }
2176  
2177      if (detach_p) {
2178          /* detached dump */
2179          s->detached = true;
2180          qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread,
2181                             s, QEMU_THREAD_DETACHED);
2182      } else {
2183          /* sync dump */
2184          dump_process(s, errp);
2185      }
2186  }
2187  
2188  DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp)
2189  {
2190      DumpGuestMemoryCapability *cap =
2191                                    g_new0(DumpGuestMemoryCapability, 1);
2192      DumpGuestMemoryFormatList **tail = &cap->formats;
2193  
2194      /* elf is always available */
2195      QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF);
2196  
2197      /* kdump-zlib is always available */
2198      QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB);
2199  
2200      /* add new item if kdump-lzo is available */
2201  #ifdef CONFIG_LZO
2202      QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO);
2203  #endif
2204  
2205      /* add new item if kdump-snappy is available */
2206  #ifdef CONFIG_SNAPPY
2207      QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY);
2208  #endif
2209  
2210      if (win_dump_available(NULL)) {
2211          QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP);
2212      }
2213  
2214      return cap;
2215  }
2216