xref: /qemu/dump/dump.c (revision d45c8332)
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 uint16_t cpu_to_dump16(DumpState *s, uint16_t val)
58 {
59     if (s->dump_info.d_endian == ELFDATA2LSB) {
60         val = cpu_to_le16(val);
61     } else {
62         val = cpu_to_be16(val);
63     }
64 
65     return val;
66 }
67 
68 uint32_t cpu_to_dump32(DumpState *s, uint32_t val)
69 {
70     if (s->dump_info.d_endian == ELFDATA2LSB) {
71         val = cpu_to_le32(val);
72     } else {
73         val = cpu_to_be32(val);
74     }
75 
76     return val;
77 }
78 
79 uint64_t cpu_to_dump64(DumpState *s, uint64_t val)
80 {
81     if (s->dump_info.d_endian == ELFDATA2LSB) {
82         val = cpu_to_le64(val);
83     } else {
84         val = cpu_to_be64(val);
85     }
86 
87     return val;
88 }
89 
90 static int dump_cleanup(DumpState *s)
91 {
92     guest_phys_blocks_free(&s->guest_phys_blocks);
93     memory_mapping_list_free(&s->list);
94     close(s->fd);
95     g_free(s->guest_note);
96     s->guest_note = NULL;
97     if (s->resume) {
98         if (s->detached) {
99             qemu_mutex_lock_iothread();
100         }
101         vm_start();
102         if (s->detached) {
103             qemu_mutex_unlock_iothread();
104         }
105     }
106     migrate_del_blocker(dump_migration_blocker);
107 
108     return 0;
109 }
110 
111 static int fd_write_vmcore(const void *buf, size_t size, void *opaque)
112 {
113     DumpState *s = opaque;
114     size_t written_size;
115 
116     written_size = qemu_write_full(s->fd, buf, size);
117     if (written_size != size) {
118         return -errno;
119     }
120 
121     return 0;
122 }
123 
124 static void write_elf64_header(DumpState *s, Error **errp)
125 {
126     Elf64_Ehdr elf_header;
127     int ret;
128 
129     memset(&elf_header, 0, sizeof(Elf64_Ehdr));
130     memcpy(&elf_header, ELFMAG, SELFMAG);
131     elf_header.e_ident[EI_CLASS] = ELFCLASS64;
132     elf_header.e_ident[EI_DATA] = s->dump_info.d_endian;
133     elf_header.e_ident[EI_VERSION] = EV_CURRENT;
134     elf_header.e_type = cpu_to_dump16(s, ET_CORE);
135     elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
136     elf_header.e_version = cpu_to_dump32(s, EV_CURRENT);
137     elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
138     elf_header.e_phoff = cpu_to_dump64(s, sizeof(Elf64_Ehdr));
139     elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr));
140     elf_header.e_phnum = cpu_to_dump16(s, s->phdr_num);
141     if (s->have_section) {
142         uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->sh_info;
143 
144         elf_header.e_shoff = cpu_to_dump64(s, shoff);
145         elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr));
146         elf_header.e_shnum = cpu_to_dump16(s, 1);
147     }
148 
149     ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
150     if (ret < 0) {
151         error_setg_errno(errp, -ret, "dump: failed to write elf header");
152     }
153 }
154 
155 static void write_elf32_header(DumpState *s, Error **errp)
156 {
157     Elf32_Ehdr elf_header;
158     int ret;
159 
160     memset(&elf_header, 0, sizeof(Elf32_Ehdr));
161     memcpy(&elf_header, ELFMAG, SELFMAG);
162     elf_header.e_ident[EI_CLASS] = ELFCLASS32;
163     elf_header.e_ident[EI_DATA] = s->dump_info.d_endian;
164     elf_header.e_ident[EI_VERSION] = EV_CURRENT;
165     elf_header.e_type = cpu_to_dump16(s, ET_CORE);
166     elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
167     elf_header.e_version = cpu_to_dump32(s, EV_CURRENT);
168     elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
169     elf_header.e_phoff = cpu_to_dump32(s, sizeof(Elf32_Ehdr));
170     elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr));
171     elf_header.e_phnum = cpu_to_dump16(s, s->phdr_num);
172     if (s->have_section) {
173         uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->sh_info;
174 
175         elf_header.e_shoff = cpu_to_dump32(s, shoff);
176         elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr));
177         elf_header.e_shnum = cpu_to_dump16(s, 1);
178     }
179 
180     ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
181     if (ret < 0) {
182         error_setg_errno(errp, -ret, "dump: failed to write elf header");
183     }
184 }
185 
186 static void write_elf64_load(DumpState *s, MemoryMapping *memory_mapping,
187                              int phdr_index, hwaddr offset,
188                              hwaddr filesz, Error **errp)
189 {
190     Elf64_Phdr phdr;
191     int ret;
192 
193     memset(&phdr, 0, sizeof(Elf64_Phdr));
194     phdr.p_type = cpu_to_dump32(s, PT_LOAD);
195     phdr.p_offset = cpu_to_dump64(s, offset);
196     phdr.p_paddr = cpu_to_dump64(s, memory_mapping->phys_addr);
197     phdr.p_filesz = cpu_to_dump64(s, filesz);
198     phdr.p_memsz = cpu_to_dump64(s, memory_mapping->length);
199     phdr.p_vaddr = cpu_to_dump64(s, memory_mapping->virt_addr) ?: phdr.p_paddr;
200 
201     assert(memory_mapping->length >= filesz);
202 
203     ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s);
204     if (ret < 0) {
205         error_setg_errno(errp, -ret,
206                          "dump: failed to write program header table");
207     }
208 }
209 
210 static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping,
211                              int phdr_index, hwaddr offset,
212                              hwaddr filesz, Error **errp)
213 {
214     Elf32_Phdr phdr;
215     int ret;
216 
217     memset(&phdr, 0, sizeof(Elf32_Phdr));
218     phdr.p_type = cpu_to_dump32(s, PT_LOAD);
219     phdr.p_offset = cpu_to_dump32(s, offset);
220     phdr.p_paddr = cpu_to_dump32(s, memory_mapping->phys_addr);
221     phdr.p_filesz = cpu_to_dump32(s, filesz);
222     phdr.p_memsz = cpu_to_dump32(s, memory_mapping->length);
223     phdr.p_vaddr =
224         cpu_to_dump32(s, memory_mapping->virt_addr) ?: phdr.p_paddr;
225 
226     assert(memory_mapping->length >= filesz);
227 
228     ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s);
229     if (ret < 0) {
230         error_setg_errno(errp, -ret,
231                          "dump: failed to write program header table");
232     }
233 }
234 
235 static void write_elf64_note(DumpState *s, Error **errp)
236 {
237     Elf64_Phdr phdr;
238     hwaddr begin = s->memory_offset - s->note_size;
239     int ret;
240 
241     memset(&phdr, 0, sizeof(Elf64_Phdr));
242     phdr.p_type = cpu_to_dump32(s, PT_NOTE);
243     phdr.p_offset = cpu_to_dump64(s, begin);
244     phdr.p_paddr = 0;
245     phdr.p_filesz = cpu_to_dump64(s, s->note_size);
246     phdr.p_memsz = cpu_to_dump64(s, s->note_size);
247     phdr.p_vaddr = 0;
248 
249     ret = fd_write_vmcore(&phdr, sizeof(Elf64_Phdr), s);
250     if (ret < 0) {
251         error_setg_errno(errp, -ret,
252                          "dump: failed to write program header table");
253     }
254 }
255 
256 static inline int cpu_index(CPUState *cpu)
257 {
258     return cpu->cpu_index + 1;
259 }
260 
261 static void write_guest_note(WriteCoreDumpFunction f, DumpState *s,
262                              Error **errp)
263 {
264     int ret;
265 
266     if (s->guest_note) {
267         ret = f(s->guest_note, s->guest_note_size, s);
268         if (ret < 0) {
269             error_setg(errp, "dump: failed to write guest note");
270         }
271     }
272 }
273 
274 static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s,
275                               Error **errp)
276 {
277     CPUState *cpu;
278     int ret;
279     int id;
280 
281     CPU_FOREACH(cpu) {
282         id = cpu_index(cpu);
283         ret = cpu_write_elf64_note(f, cpu, id, s);
284         if (ret < 0) {
285             error_setg(errp, "dump: failed to write elf notes");
286             return;
287         }
288     }
289 
290     CPU_FOREACH(cpu) {
291         ret = cpu_write_elf64_qemunote(f, cpu, s);
292         if (ret < 0) {
293             error_setg(errp, "dump: failed to write CPU status");
294             return;
295         }
296     }
297 
298     write_guest_note(f, s, errp);
299 }
300 
301 static void write_elf32_note(DumpState *s, Error **errp)
302 {
303     hwaddr begin = s->memory_offset - s->note_size;
304     Elf32_Phdr phdr;
305     int ret;
306 
307     memset(&phdr, 0, sizeof(Elf32_Phdr));
308     phdr.p_type = cpu_to_dump32(s, PT_NOTE);
309     phdr.p_offset = cpu_to_dump32(s, begin);
310     phdr.p_paddr = 0;
311     phdr.p_filesz = cpu_to_dump32(s, s->note_size);
312     phdr.p_memsz = cpu_to_dump32(s, s->note_size);
313     phdr.p_vaddr = 0;
314 
315     ret = fd_write_vmcore(&phdr, sizeof(Elf32_Phdr), s);
316     if (ret < 0) {
317         error_setg_errno(errp, -ret,
318                          "dump: failed to write program header table");
319     }
320 }
321 
322 static void write_elf32_notes(WriteCoreDumpFunction f, DumpState *s,
323                               Error **errp)
324 {
325     CPUState *cpu;
326     int ret;
327     int id;
328 
329     CPU_FOREACH(cpu) {
330         id = cpu_index(cpu);
331         ret = cpu_write_elf32_note(f, cpu, id, s);
332         if (ret < 0) {
333             error_setg(errp, "dump: failed to write elf notes");
334             return;
335         }
336     }
337 
338     CPU_FOREACH(cpu) {
339         ret = cpu_write_elf32_qemunote(f, cpu, s);
340         if (ret < 0) {
341             error_setg(errp, "dump: failed to write CPU status");
342             return;
343         }
344     }
345 
346     write_guest_note(f, s, errp);
347 }
348 
349 static void write_elf_section(DumpState *s, int type, Error **errp)
350 {
351     Elf32_Shdr shdr32;
352     Elf64_Shdr shdr64;
353     int shdr_size;
354     void *shdr;
355     int ret;
356 
357     if (type == 0) {
358         shdr_size = sizeof(Elf32_Shdr);
359         memset(&shdr32, 0, shdr_size);
360         shdr32.sh_info = cpu_to_dump32(s, s->sh_info);
361         shdr = &shdr32;
362     } else {
363         shdr_size = sizeof(Elf64_Shdr);
364         memset(&shdr64, 0, shdr_size);
365         shdr64.sh_info = cpu_to_dump32(s, s->sh_info);
366         shdr = &shdr64;
367     }
368 
369     ret = fd_write_vmcore(shdr, shdr_size, s);
370     if (ret < 0) {
371         error_setg_errno(errp, -ret,
372                          "dump: failed to write section header table");
373     }
374 }
375 
376 static void write_data(DumpState *s, void *buf, int length, Error **errp)
377 {
378     int ret;
379 
380     ret = fd_write_vmcore(buf, length, s);
381     if (ret < 0) {
382         error_setg_errno(errp, -ret, "dump: failed to save memory");
383     } else {
384         s->written_size += length;
385     }
386 }
387 
388 /* write the memory to vmcore. 1 page per I/O. */
389 static void write_memory(DumpState *s, GuestPhysBlock *block, ram_addr_t start,
390                          int64_t size, Error **errp)
391 {
392     int64_t i;
393     Error *local_err = NULL;
394 
395     for (i = 0; i < size / s->dump_info.page_size; i++) {
396         write_data(s, block->host_addr + start + i * s->dump_info.page_size,
397                    s->dump_info.page_size, &local_err);
398         if (local_err) {
399             error_propagate(errp, local_err);
400             return;
401         }
402     }
403 
404     if ((size % s->dump_info.page_size) != 0) {
405         write_data(s, block->host_addr + start + i * s->dump_info.page_size,
406                    size % s->dump_info.page_size, &local_err);
407         if (local_err) {
408             error_propagate(errp, local_err);
409             return;
410         }
411     }
412 }
413 
414 /* get the memory's offset and size in the vmcore */
415 static void get_offset_range(hwaddr phys_addr,
416                              ram_addr_t mapping_length,
417                              DumpState *s,
418                              hwaddr *p_offset,
419                              hwaddr *p_filesz)
420 {
421     GuestPhysBlock *block;
422     hwaddr offset = s->memory_offset;
423     int64_t size_in_block, start;
424 
425     /* When the memory is not stored into vmcore, offset will be -1 */
426     *p_offset = -1;
427     *p_filesz = 0;
428 
429     if (s->has_filter) {
430         if (phys_addr < s->begin || phys_addr >= s->begin + s->length) {
431             return;
432         }
433     }
434 
435     QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
436         if (s->has_filter) {
437             if (block->target_start >= s->begin + s->length ||
438                 block->target_end <= s->begin) {
439                 /* This block is out of the range */
440                 continue;
441             }
442 
443             if (s->begin <= block->target_start) {
444                 start = block->target_start;
445             } else {
446                 start = s->begin;
447             }
448 
449             size_in_block = block->target_end - start;
450             if (s->begin + s->length < block->target_end) {
451                 size_in_block -= block->target_end - (s->begin + s->length);
452             }
453         } else {
454             start = block->target_start;
455             size_in_block = block->target_end - block->target_start;
456         }
457 
458         if (phys_addr >= start && phys_addr < start + size_in_block) {
459             *p_offset = phys_addr - start + offset;
460 
461             /* The offset range mapped from the vmcore file must not spill over
462              * the GuestPhysBlock, clamp it. The rest of the mapping will be
463              * zero-filled in memory at load time; see
464              * <http://refspecs.linuxbase.org/elf/gabi4+/ch5.pheader.html>.
465              */
466             *p_filesz = phys_addr + mapping_length <= start + size_in_block ?
467                         mapping_length :
468                         size_in_block - (phys_addr - start);
469             return;
470         }
471 
472         offset += size_in_block;
473     }
474 }
475 
476 static void write_elf_loads(DumpState *s, Error **errp)
477 {
478     hwaddr offset, filesz;
479     MemoryMapping *memory_mapping;
480     uint32_t phdr_index = 1;
481     uint32_t max_index;
482     Error *local_err = NULL;
483 
484     if (s->have_section) {
485         max_index = s->sh_info;
486     } else {
487         max_index = s->phdr_num;
488     }
489 
490     QTAILQ_FOREACH(memory_mapping, &s->list.head, next) {
491         get_offset_range(memory_mapping->phys_addr,
492                          memory_mapping->length,
493                          s, &offset, &filesz);
494         if (s->dump_info.d_class == ELFCLASS64) {
495             write_elf64_load(s, memory_mapping, phdr_index++, offset,
496                              filesz, &local_err);
497         } else {
498             write_elf32_load(s, memory_mapping, phdr_index++, offset,
499                              filesz, &local_err);
500         }
501 
502         if (local_err) {
503             error_propagate(errp, local_err);
504             return;
505         }
506 
507         if (phdr_index >= max_index) {
508             break;
509         }
510     }
511 }
512 
513 /* write elf header, PT_NOTE and elf note to vmcore. */
514 static void dump_begin(DumpState *s, Error **errp)
515 {
516     Error *local_err = NULL;
517 
518     /*
519      * the vmcore's format is:
520      *   --------------
521      *   |  elf header |
522      *   --------------
523      *   |  PT_NOTE    |
524      *   --------------
525      *   |  PT_LOAD    |
526      *   --------------
527      *   |  ......     |
528      *   --------------
529      *   |  PT_LOAD    |
530      *   --------------
531      *   |  sec_hdr    |
532      *   --------------
533      *   |  elf note   |
534      *   --------------
535      *   |  memory     |
536      *   --------------
537      *
538      * we only know where the memory is saved after we write elf note into
539      * vmcore.
540      */
541 
542     /* write elf header to vmcore */
543     if (s->dump_info.d_class == ELFCLASS64) {
544         write_elf64_header(s, &local_err);
545     } else {
546         write_elf32_header(s, &local_err);
547     }
548     if (local_err) {
549         error_propagate(errp, local_err);
550         return;
551     }
552 
553     if (s->dump_info.d_class == ELFCLASS64) {
554         /* write PT_NOTE to vmcore */
555         write_elf64_note(s, &local_err);
556         if (local_err) {
557             error_propagate(errp, local_err);
558             return;
559         }
560 
561         /* write all PT_LOAD to vmcore */
562         write_elf_loads(s, &local_err);
563         if (local_err) {
564             error_propagate(errp, local_err);
565             return;
566         }
567 
568         /* write section to vmcore */
569         if (s->have_section) {
570             write_elf_section(s, 1, &local_err);
571             if (local_err) {
572                 error_propagate(errp, local_err);
573                 return;
574             }
575         }
576 
577         /* write notes to vmcore */
578         write_elf64_notes(fd_write_vmcore, s, &local_err);
579         if (local_err) {
580             error_propagate(errp, local_err);
581             return;
582         }
583     } else {
584         /* write PT_NOTE to vmcore */
585         write_elf32_note(s, &local_err);
586         if (local_err) {
587             error_propagate(errp, local_err);
588             return;
589         }
590 
591         /* write all PT_LOAD to vmcore */
592         write_elf_loads(s, &local_err);
593         if (local_err) {
594             error_propagate(errp, local_err);
595             return;
596         }
597 
598         /* write section to vmcore */
599         if (s->have_section) {
600             write_elf_section(s, 0, &local_err);
601             if (local_err) {
602                 error_propagate(errp, local_err);
603                 return;
604             }
605         }
606 
607         /* write notes to vmcore */
608         write_elf32_notes(fd_write_vmcore, s, &local_err);
609         if (local_err) {
610             error_propagate(errp, local_err);
611             return;
612         }
613     }
614 }
615 
616 static int get_next_block(DumpState *s, GuestPhysBlock *block)
617 {
618     while (1) {
619         block = QTAILQ_NEXT(block, next);
620         if (!block) {
621             /* no more block */
622             return 1;
623         }
624 
625         s->start = 0;
626         s->next_block = block;
627         if (s->has_filter) {
628             if (block->target_start >= s->begin + s->length ||
629                 block->target_end <= s->begin) {
630                 /* This block is out of the range */
631                 continue;
632             }
633 
634             if (s->begin > block->target_start) {
635                 s->start = s->begin - block->target_start;
636             }
637         }
638 
639         return 0;
640     }
641 }
642 
643 /* write all memory to vmcore */
644 static void dump_iterate(DumpState *s, Error **errp)
645 {
646     GuestPhysBlock *block;
647     int64_t size;
648     Error *local_err = NULL;
649 
650     do {
651         block = s->next_block;
652 
653         size = block->target_end - block->target_start;
654         if (s->has_filter) {
655             size -= s->start;
656             if (s->begin + s->length < block->target_end) {
657                 size -= block->target_end - (s->begin + s->length);
658             }
659         }
660         write_memory(s, block, s->start, size, &local_err);
661         if (local_err) {
662             error_propagate(errp, local_err);
663             return;
664         }
665 
666     } while (!get_next_block(s, block));
667 }
668 
669 static void create_vmcore(DumpState *s, Error **errp)
670 {
671     Error *local_err = NULL;
672 
673     dump_begin(s, &local_err);
674     if (local_err) {
675         error_propagate(errp, local_err);
676         return;
677     }
678 
679     dump_iterate(s, errp);
680 }
681 
682 static int write_start_flat_header(int fd)
683 {
684     MakedumpfileHeader *mh;
685     int ret = 0;
686 
687     QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER);
688     mh = g_malloc0(MAX_SIZE_MDF_HEADER);
689 
690     memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE,
691            MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE));
692 
693     mh->type = cpu_to_be64(TYPE_FLAT_HEADER);
694     mh->version = cpu_to_be64(VERSION_FLAT_HEADER);
695 
696     size_t written_size;
697     written_size = qemu_write_full(fd, mh, MAX_SIZE_MDF_HEADER);
698     if (written_size != MAX_SIZE_MDF_HEADER) {
699         ret = -1;
700     }
701 
702     g_free(mh);
703     return ret;
704 }
705 
706 static int write_end_flat_header(int fd)
707 {
708     MakedumpfileDataHeader mdh;
709 
710     mdh.offset = END_FLAG_FLAT_HEADER;
711     mdh.buf_size = END_FLAG_FLAT_HEADER;
712 
713     size_t written_size;
714     written_size = qemu_write_full(fd, &mdh, sizeof(mdh));
715     if (written_size != sizeof(mdh)) {
716         return -1;
717     }
718 
719     return 0;
720 }
721 
722 static int write_buffer(int fd, off_t offset, const void *buf, size_t size)
723 {
724     size_t written_size;
725     MakedumpfileDataHeader mdh;
726 
727     mdh.offset = cpu_to_be64(offset);
728     mdh.buf_size = cpu_to_be64(size);
729 
730     written_size = qemu_write_full(fd, &mdh, sizeof(mdh));
731     if (written_size != sizeof(mdh)) {
732         return -1;
733     }
734 
735     written_size = qemu_write_full(fd, buf, size);
736     if (written_size != size) {
737         return -1;
738     }
739 
740     return 0;
741 }
742 
743 static int buf_write_note(const void *buf, size_t size, void *opaque)
744 {
745     DumpState *s = opaque;
746 
747     /* note_buf is not enough */
748     if (s->note_buf_offset + size > s->note_size) {
749         return -1;
750     }
751 
752     memcpy(s->note_buf + s->note_buf_offset, buf, size);
753 
754     s->note_buf_offset += size;
755 
756     return 0;
757 }
758 
759 /*
760  * This function retrieves various sizes from an elf header.
761  *
762  * @note has to be a valid ELF note. The return sizes are unmodified
763  * (not padded or rounded up to be multiple of 4).
764  */
765 static void get_note_sizes(DumpState *s, const void *note,
766                            uint64_t *note_head_size,
767                            uint64_t *name_size,
768                            uint64_t *desc_size)
769 {
770     uint64_t note_head_sz;
771     uint64_t name_sz;
772     uint64_t desc_sz;
773 
774     if (s->dump_info.d_class == ELFCLASS64) {
775         const Elf64_Nhdr *hdr = note;
776         note_head_sz = sizeof(Elf64_Nhdr);
777         name_sz = tswap64(hdr->n_namesz);
778         desc_sz = tswap64(hdr->n_descsz);
779     } else {
780         const Elf32_Nhdr *hdr = note;
781         note_head_sz = sizeof(Elf32_Nhdr);
782         name_sz = tswap32(hdr->n_namesz);
783         desc_sz = tswap32(hdr->n_descsz);
784     }
785 
786     if (note_head_size) {
787         *note_head_size = note_head_sz;
788     }
789     if (name_size) {
790         *name_size = name_sz;
791     }
792     if (desc_size) {
793         *desc_size = desc_sz;
794     }
795 }
796 
797 static bool note_name_equal(DumpState *s,
798                             const uint8_t *note, const char *name)
799 {
800     int len = strlen(name) + 1;
801     uint64_t head_size, name_size;
802 
803     get_note_sizes(s, note, &head_size, &name_size, NULL);
804     head_size = ROUND_UP(head_size, 4);
805 
806     return name_size == len && memcmp(note + head_size, name, len) == 0;
807 }
808 
809 /* write common header, sub header and elf note to vmcore */
810 static void create_header32(DumpState *s, Error **errp)
811 {
812     DiskDumpHeader32 *dh = NULL;
813     KdumpSubHeader32 *kh = NULL;
814     size_t size;
815     uint32_t block_size;
816     uint32_t sub_hdr_size;
817     uint32_t bitmap_blocks;
818     uint32_t status = 0;
819     uint64_t offset_note;
820     Error *local_err = NULL;
821 
822     /* write common header, the version of kdump-compressed format is 6th */
823     size = sizeof(DiskDumpHeader32);
824     dh = g_malloc0(size);
825 
826     memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN);
827     dh->header_version = cpu_to_dump32(s, 6);
828     block_size = s->dump_info.page_size;
829     dh->block_size = cpu_to_dump32(s, block_size);
830     sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size;
831     sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
832     dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size);
833     /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */
834     dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX));
835     dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus);
836     bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2;
837     dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks);
838     strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine));
839 
840     if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) {
841         status |= DUMP_DH_COMPRESSED_ZLIB;
842     }
843 #ifdef CONFIG_LZO
844     if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) {
845         status |= DUMP_DH_COMPRESSED_LZO;
846     }
847 #endif
848 #ifdef CONFIG_SNAPPY
849     if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) {
850         status |= DUMP_DH_COMPRESSED_SNAPPY;
851     }
852 #endif
853     dh->status = cpu_to_dump32(s, status);
854 
855     if (write_buffer(s->fd, 0, dh, size) < 0) {
856         error_setg(errp, "dump: failed to write disk dump header");
857         goto out;
858     }
859 
860     /* write sub header */
861     size = sizeof(KdumpSubHeader32);
862     kh = g_malloc0(size);
863 
864     /* 64bit max_mapnr_64 */
865     kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr);
866     kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base);
867     kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
868 
869     offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
870     if (s->guest_note &&
871         note_name_equal(s, s->guest_note, "VMCOREINFO")) {
872         uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo;
873 
874         get_note_sizes(s, s->guest_note,
875                        &hsize, &name_size, &size_vmcoreinfo_desc);
876         offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size +
877             (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
878         kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
879         kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo_desc);
880     }
881 
882     kh->offset_note = cpu_to_dump64(s, offset_note);
883     kh->note_size = cpu_to_dump32(s, s->note_size);
884 
885     if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS *
886                      block_size, kh, size) < 0) {
887         error_setg(errp, "dump: failed to write kdump sub header");
888         goto out;
889     }
890 
891     /* write note */
892     s->note_buf = g_malloc0(s->note_size);
893     s->note_buf_offset = 0;
894 
895     /* use s->note_buf to store notes temporarily */
896     write_elf32_notes(buf_write_note, s, &local_err);
897     if (local_err) {
898         error_propagate(errp, local_err);
899         goto out;
900     }
901     if (write_buffer(s->fd, offset_note, s->note_buf,
902                      s->note_size) < 0) {
903         error_setg(errp, "dump: failed to write notes");
904         goto out;
905     }
906 
907     /* get offset of dump_bitmap */
908     s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) *
909                              block_size;
910 
911     /* get offset of page */
912     s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) *
913                      block_size;
914 
915 out:
916     g_free(dh);
917     g_free(kh);
918     g_free(s->note_buf);
919 }
920 
921 /* write common header, sub header and elf note to vmcore */
922 static void create_header64(DumpState *s, Error **errp)
923 {
924     DiskDumpHeader64 *dh = NULL;
925     KdumpSubHeader64 *kh = NULL;
926     size_t size;
927     uint32_t block_size;
928     uint32_t sub_hdr_size;
929     uint32_t bitmap_blocks;
930     uint32_t status = 0;
931     uint64_t offset_note;
932     Error *local_err = NULL;
933 
934     /* write common header, the version of kdump-compressed format is 6th */
935     size = sizeof(DiskDumpHeader64);
936     dh = g_malloc0(size);
937 
938     memcpy(dh->signature, KDUMP_SIGNATURE, SIG_LEN);
939     dh->header_version = cpu_to_dump32(s, 6);
940     block_size = s->dump_info.page_size;
941     dh->block_size = cpu_to_dump32(s, block_size);
942     sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size;
943     sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
944     dh->sub_hdr_size = cpu_to_dump32(s, sub_hdr_size);
945     /* dh->max_mapnr may be truncated, full 64bit is in kh.max_mapnr_64 */
946     dh->max_mapnr = cpu_to_dump32(s, MIN(s->max_mapnr, UINT_MAX));
947     dh->nr_cpus = cpu_to_dump32(s, s->nr_cpus);
948     bitmap_blocks = DIV_ROUND_UP(s->len_dump_bitmap, block_size) * 2;
949     dh->bitmap_blocks = cpu_to_dump32(s, bitmap_blocks);
950     strncpy(dh->utsname.machine, ELF_MACHINE_UNAME, sizeof(dh->utsname.machine));
951 
952     if (s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) {
953         status |= DUMP_DH_COMPRESSED_ZLIB;
954     }
955 #ifdef CONFIG_LZO
956     if (s->flag_compress & DUMP_DH_COMPRESSED_LZO) {
957         status |= DUMP_DH_COMPRESSED_LZO;
958     }
959 #endif
960 #ifdef CONFIG_SNAPPY
961     if (s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) {
962         status |= DUMP_DH_COMPRESSED_SNAPPY;
963     }
964 #endif
965     dh->status = cpu_to_dump32(s, status);
966 
967     if (write_buffer(s->fd, 0, dh, size) < 0) {
968         error_setg(errp, "dump: failed to write disk dump header");
969         goto out;
970     }
971 
972     /* write sub header */
973     size = sizeof(KdumpSubHeader64);
974     kh = g_malloc0(size);
975 
976     /* 64bit max_mapnr_64 */
977     kh->max_mapnr_64 = cpu_to_dump64(s, s->max_mapnr);
978     kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base);
979     kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
980 
981     offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
982     if (s->guest_note &&
983         note_name_equal(s, s->guest_note, "VMCOREINFO")) {
984         uint64_t hsize, name_size, size_vmcoreinfo_desc, offset_vmcoreinfo;
985 
986         get_note_sizes(s, s->guest_note,
987                        &hsize, &name_size, &size_vmcoreinfo_desc);
988         offset_vmcoreinfo = offset_note + s->note_size - s->guest_note_size +
989             (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
990         kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
991         kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo_desc);
992     }
993 
994     kh->offset_note = cpu_to_dump64(s, offset_note);
995     kh->note_size = cpu_to_dump64(s, s->note_size);
996 
997     if (write_buffer(s->fd, DISKDUMP_HEADER_BLOCKS *
998                      block_size, kh, size) < 0) {
999         error_setg(errp, "dump: failed to write kdump sub header");
1000         goto out;
1001     }
1002 
1003     /* write note */
1004     s->note_buf = g_malloc0(s->note_size);
1005     s->note_buf_offset = 0;
1006 
1007     /* use s->note_buf to store notes temporarily */
1008     write_elf64_notes(buf_write_note, s, &local_err);
1009     if (local_err) {
1010         error_propagate(errp, local_err);
1011         goto out;
1012     }
1013 
1014     if (write_buffer(s->fd, offset_note, s->note_buf,
1015                      s->note_size) < 0) {
1016         error_setg(errp, "dump: failed to write notes");
1017         goto out;
1018     }
1019 
1020     /* get offset of dump_bitmap */
1021     s->offset_dump_bitmap = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size) *
1022                              block_size;
1023 
1024     /* get offset of page */
1025     s->offset_page = (DISKDUMP_HEADER_BLOCKS + sub_hdr_size + bitmap_blocks) *
1026                      block_size;
1027 
1028 out:
1029     g_free(dh);
1030     g_free(kh);
1031     g_free(s->note_buf);
1032 }
1033 
1034 static void write_dump_header(DumpState *s, Error **errp)
1035 {
1036     if (s->dump_info.d_class == ELFCLASS32) {
1037         create_header32(s, errp);
1038     } else {
1039         create_header64(s, errp);
1040     }
1041 }
1042 
1043 static size_t dump_bitmap_get_bufsize(DumpState *s)
1044 {
1045     return s->dump_info.page_size;
1046 }
1047 
1048 /*
1049  * set dump_bitmap sequencely. the bit before last_pfn is not allowed to be
1050  * rewritten, so if need to set the first bit, set last_pfn and pfn to 0.
1051  * set_dump_bitmap will always leave the recently set bit un-sync. And setting
1052  * (last bit + sizeof(buf) * 8) to 0 will do flushing the content in buf into
1053  * vmcore, ie. synchronizing un-sync bit into vmcore.
1054  */
1055 static int set_dump_bitmap(uint64_t last_pfn, uint64_t pfn, bool value,
1056                            uint8_t *buf, DumpState *s)
1057 {
1058     off_t old_offset, new_offset;
1059     off_t offset_bitmap1, offset_bitmap2;
1060     uint32_t byte, bit;
1061     size_t bitmap_bufsize = dump_bitmap_get_bufsize(s);
1062     size_t bits_per_buf = bitmap_bufsize * CHAR_BIT;
1063 
1064     /* should not set the previous place */
1065     assert(last_pfn <= pfn);
1066 
1067     /*
1068      * if the bit needed to be set is not cached in buf, flush the data in buf
1069      * to vmcore firstly.
1070      * making new_offset be bigger than old_offset can also sync remained data
1071      * into vmcore.
1072      */
1073     old_offset = bitmap_bufsize * (last_pfn / bits_per_buf);
1074     new_offset = bitmap_bufsize * (pfn / bits_per_buf);
1075 
1076     while (old_offset < new_offset) {
1077         /* calculate the offset and write dump_bitmap */
1078         offset_bitmap1 = s->offset_dump_bitmap + old_offset;
1079         if (write_buffer(s->fd, offset_bitmap1, buf,
1080                          bitmap_bufsize) < 0) {
1081             return -1;
1082         }
1083 
1084         /* dump level 1 is chosen, so 1st and 2nd bitmap are same */
1085         offset_bitmap2 = s->offset_dump_bitmap + s->len_dump_bitmap +
1086                          old_offset;
1087         if (write_buffer(s->fd, offset_bitmap2, buf,
1088                          bitmap_bufsize) < 0) {
1089             return -1;
1090         }
1091 
1092         memset(buf, 0, bitmap_bufsize);
1093         old_offset += bitmap_bufsize;
1094     }
1095 
1096     /* get the exact place of the bit in the buf, and set it */
1097     byte = (pfn % bits_per_buf) / CHAR_BIT;
1098     bit = (pfn % bits_per_buf) % CHAR_BIT;
1099     if (value) {
1100         buf[byte] |= 1u << bit;
1101     } else {
1102         buf[byte] &= ~(1u << bit);
1103     }
1104 
1105     return 0;
1106 }
1107 
1108 static uint64_t dump_paddr_to_pfn(DumpState *s, uint64_t addr)
1109 {
1110     int target_page_shift = ctz32(s->dump_info.page_size);
1111 
1112     return (addr >> target_page_shift) - ARCH_PFN_OFFSET;
1113 }
1114 
1115 static uint64_t dump_pfn_to_paddr(DumpState *s, uint64_t pfn)
1116 {
1117     int target_page_shift = ctz32(s->dump_info.page_size);
1118 
1119     return (pfn + ARCH_PFN_OFFSET) << target_page_shift;
1120 }
1121 
1122 /*
1123  * exam every page and return the page frame number and the address of the page.
1124  * bufptr can be NULL. note: the blocks here is supposed to reflect guest-phys
1125  * blocks, so block->target_start and block->target_end should be interal
1126  * multiples of the target page size.
1127  */
1128 static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
1129                           uint8_t **bufptr, DumpState *s)
1130 {
1131     GuestPhysBlock *block = *blockptr;
1132     hwaddr addr, target_page_mask = ~((hwaddr)s->dump_info.page_size - 1);
1133     uint8_t *buf;
1134 
1135     /* block == NULL means the start of the iteration */
1136     if (!block) {
1137         block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
1138         *blockptr = block;
1139         assert((block->target_start & ~target_page_mask) == 0);
1140         assert((block->target_end & ~target_page_mask) == 0);
1141         *pfnptr = dump_paddr_to_pfn(s, block->target_start);
1142         if (bufptr) {
1143             *bufptr = block->host_addr;
1144         }
1145         return true;
1146     }
1147 
1148     *pfnptr = *pfnptr + 1;
1149     addr = dump_pfn_to_paddr(s, *pfnptr);
1150 
1151     if ((addr >= block->target_start) &&
1152         (addr + s->dump_info.page_size <= block->target_end)) {
1153         buf = block->host_addr + (addr - block->target_start);
1154     } else {
1155         /* the next page is in the next block */
1156         block = QTAILQ_NEXT(block, next);
1157         *blockptr = block;
1158         if (!block) {
1159             return false;
1160         }
1161         assert((block->target_start & ~target_page_mask) == 0);
1162         assert((block->target_end & ~target_page_mask) == 0);
1163         *pfnptr = dump_paddr_to_pfn(s, block->target_start);
1164         buf = block->host_addr;
1165     }
1166 
1167     if (bufptr) {
1168         *bufptr = buf;
1169     }
1170 
1171     return true;
1172 }
1173 
1174 static void write_dump_bitmap(DumpState *s, Error **errp)
1175 {
1176     int ret = 0;
1177     uint64_t last_pfn, pfn;
1178     void *dump_bitmap_buf;
1179     size_t num_dumpable;
1180     GuestPhysBlock *block_iter = NULL;
1181     size_t bitmap_bufsize = dump_bitmap_get_bufsize(s);
1182     size_t bits_per_buf = bitmap_bufsize * CHAR_BIT;
1183 
1184     /* dump_bitmap_buf is used to store dump_bitmap temporarily */
1185     dump_bitmap_buf = g_malloc0(bitmap_bufsize);
1186 
1187     num_dumpable = 0;
1188     last_pfn = 0;
1189 
1190     /*
1191      * exam memory page by page, and set the bit in dump_bitmap corresponded
1192      * to the existing page.
1193      */
1194     while (get_next_page(&block_iter, &pfn, NULL, s)) {
1195         ret = set_dump_bitmap(last_pfn, pfn, true, dump_bitmap_buf, s);
1196         if (ret < 0) {
1197             error_setg(errp, "dump: failed to set dump_bitmap");
1198             goto out;
1199         }
1200 
1201         last_pfn = pfn;
1202         num_dumpable++;
1203     }
1204 
1205     /*
1206      * set_dump_bitmap will always leave the recently set bit un-sync. Here we
1207      * set the remaining bits from last_pfn to the end of the bitmap buffer to
1208      * 0. With those set, the un-sync bit will be synchronized into the vmcore.
1209      */
1210     if (num_dumpable > 0) {
1211         ret = set_dump_bitmap(last_pfn, last_pfn + bits_per_buf, false,
1212                               dump_bitmap_buf, s);
1213         if (ret < 0) {
1214             error_setg(errp, "dump: failed to sync dump_bitmap");
1215             goto out;
1216         }
1217     }
1218 
1219     /* number of dumpable pages that will be dumped later */
1220     s->num_dumpable = num_dumpable;
1221 
1222 out:
1223     g_free(dump_bitmap_buf);
1224 }
1225 
1226 static void prepare_data_cache(DataCache *data_cache, DumpState *s,
1227                                off_t offset)
1228 {
1229     data_cache->fd = s->fd;
1230     data_cache->data_size = 0;
1231     data_cache->buf_size = 4 * dump_bitmap_get_bufsize(s);
1232     data_cache->buf = g_malloc0(data_cache->buf_size);
1233     data_cache->offset = offset;
1234 }
1235 
1236 static int write_cache(DataCache *dc, const void *buf, size_t size,
1237                        bool flag_sync)
1238 {
1239     /*
1240      * dc->buf_size should not be less than size, otherwise dc will never be
1241      * enough
1242      */
1243     assert(size <= dc->buf_size);
1244 
1245     /*
1246      * if flag_sync is set, synchronize data in dc->buf into vmcore.
1247      * otherwise check if the space is enough for caching data in buf, if not,
1248      * write the data in dc->buf to dc->fd and reset dc->buf
1249      */
1250     if ((!flag_sync && dc->data_size + size > dc->buf_size) ||
1251         (flag_sync && dc->data_size > 0)) {
1252         if (write_buffer(dc->fd, dc->offset, dc->buf, dc->data_size) < 0) {
1253             return -1;
1254         }
1255 
1256         dc->offset += dc->data_size;
1257         dc->data_size = 0;
1258     }
1259 
1260     if (!flag_sync) {
1261         memcpy(dc->buf + dc->data_size, buf, size);
1262         dc->data_size += size;
1263     }
1264 
1265     return 0;
1266 }
1267 
1268 static void free_data_cache(DataCache *data_cache)
1269 {
1270     g_free(data_cache->buf);
1271 }
1272 
1273 static size_t get_len_buf_out(size_t page_size, uint32_t flag_compress)
1274 {
1275     switch (flag_compress) {
1276     case DUMP_DH_COMPRESSED_ZLIB:
1277         return compressBound(page_size);
1278 
1279     case DUMP_DH_COMPRESSED_LZO:
1280         /*
1281          * LZO will expand incompressible data by a little amount. Please check
1282          * the following URL to see the expansion calculation:
1283          * http://www.oberhumer.com/opensource/lzo/lzofaq.php
1284          */
1285         return page_size + page_size / 16 + 64 + 3;
1286 
1287 #ifdef CONFIG_SNAPPY
1288     case DUMP_DH_COMPRESSED_SNAPPY:
1289         return snappy_max_compressed_length(page_size);
1290 #endif
1291     }
1292     return 0;
1293 }
1294 
1295 static void write_dump_pages(DumpState *s, Error **errp)
1296 {
1297     int ret = 0;
1298     DataCache page_desc, page_data;
1299     size_t len_buf_out, size_out;
1300 #ifdef CONFIG_LZO
1301     lzo_bytep wrkmem = NULL;
1302 #endif
1303     uint8_t *buf_out = NULL;
1304     off_t offset_desc, offset_data;
1305     PageDescriptor pd, pd_zero;
1306     uint8_t *buf;
1307     GuestPhysBlock *block_iter = NULL;
1308     uint64_t pfn_iter;
1309 
1310     /* get offset of page_desc and page_data in dump file */
1311     offset_desc = s->offset_page;
1312     offset_data = offset_desc + sizeof(PageDescriptor) * s->num_dumpable;
1313 
1314     prepare_data_cache(&page_desc, s, offset_desc);
1315     prepare_data_cache(&page_data, s, offset_data);
1316 
1317     /* prepare buffer to store compressed data */
1318     len_buf_out = get_len_buf_out(s->dump_info.page_size, s->flag_compress);
1319     assert(len_buf_out != 0);
1320 
1321 #ifdef CONFIG_LZO
1322     wrkmem = g_malloc(LZO1X_1_MEM_COMPRESS);
1323 #endif
1324 
1325     buf_out = g_malloc(len_buf_out);
1326 
1327     /*
1328      * init zero page's page_desc and page_data, because every zero page
1329      * uses the same page_data
1330      */
1331     pd_zero.size = cpu_to_dump32(s, s->dump_info.page_size);
1332     pd_zero.flags = cpu_to_dump32(s, 0);
1333     pd_zero.offset = cpu_to_dump64(s, offset_data);
1334     pd_zero.page_flags = cpu_to_dump64(s, 0);
1335     buf = g_malloc0(s->dump_info.page_size);
1336     ret = write_cache(&page_data, buf, s->dump_info.page_size, false);
1337     g_free(buf);
1338     if (ret < 0) {
1339         error_setg(errp, "dump: failed to write page data (zero page)");
1340         goto out;
1341     }
1342 
1343     offset_data += s->dump_info.page_size;
1344 
1345     /*
1346      * dump memory to vmcore page by page. zero page will all be resided in the
1347      * first page of page section
1348      */
1349     while (get_next_page(&block_iter, &pfn_iter, &buf, s)) {
1350         /* check zero page */
1351         if (buffer_is_zero(buf, s->dump_info.page_size)) {
1352             ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor),
1353                               false);
1354             if (ret < 0) {
1355                 error_setg(errp, "dump: failed to write page desc");
1356                 goto out;
1357             }
1358         } else {
1359             /*
1360              * not zero page, then:
1361              * 1. compress the page
1362              * 2. write the compressed page into the cache of page_data
1363              * 3. get page desc of the compressed page and write it into the
1364              *    cache of page_desc
1365              *
1366              * only one compression format will be used here, for
1367              * s->flag_compress is set. But when compression fails to work,
1368              * we fall back to save in plaintext.
1369              */
1370              size_out = len_buf_out;
1371              if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) &&
1372                     (compress2(buf_out, (uLongf *)&size_out, buf,
1373                                s->dump_info.page_size, Z_BEST_SPEED) == Z_OK) &&
1374                     (size_out < s->dump_info.page_size)) {
1375                 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_ZLIB);
1376                 pd.size  = cpu_to_dump32(s, size_out);
1377 
1378                 ret = write_cache(&page_data, buf_out, size_out, false);
1379                 if (ret < 0) {
1380                     error_setg(errp, "dump: failed to write page data");
1381                     goto out;
1382                 }
1383 #ifdef CONFIG_LZO
1384             } else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) &&
1385                     (lzo1x_1_compress(buf, s->dump_info.page_size, buf_out,
1386                     (lzo_uint *)&size_out, wrkmem) == LZO_E_OK) &&
1387                     (size_out < s->dump_info.page_size)) {
1388                 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_LZO);
1389                 pd.size  = cpu_to_dump32(s, size_out);
1390 
1391                 ret = write_cache(&page_data, buf_out, size_out, false);
1392                 if (ret < 0) {
1393                     error_setg(errp, "dump: failed to write page data");
1394                     goto out;
1395                 }
1396 #endif
1397 #ifdef CONFIG_SNAPPY
1398             } else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) &&
1399                     (snappy_compress((char *)buf, s->dump_info.page_size,
1400                     (char *)buf_out, &size_out) == SNAPPY_OK) &&
1401                     (size_out < s->dump_info.page_size)) {
1402                 pd.flags = cpu_to_dump32(s, DUMP_DH_COMPRESSED_SNAPPY);
1403                 pd.size  = cpu_to_dump32(s, size_out);
1404 
1405                 ret = write_cache(&page_data, buf_out, size_out, false);
1406                 if (ret < 0) {
1407                     error_setg(errp, "dump: failed to write page data");
1408                     goto out;
1409                 }
1410 #endif
1411             } else {
1412                 /*
1413                  * fall back to save in plaintext, size_out should be
1414                  * assigned the target's page size
1415                  */
1416                 pd.flags = cpu_to_dump32(s, 0);
1417                 size_out = s->dump_info.page_size;
1418                 pd.size = cpu_to_dump32(s, size_out);
1419 
1420                 ret = write_cache(&page_data, buf,
1421                                   s->dump_info.page_size, false);
1422                 if (ret < 0) {
1423                     error_setg(errp, "dump: failed to write page data");
1424                     goto out;
1425                 }
1426             }
1427 
1428             /* get and write page desc here */
1429             pd.page_flags = cpu_to_dump64(s, 0);
1430             pd.offset = cpu_to_dump64(s, offset_data);
1431             offset_data += size_out;
1432 
1433             ret = write_cache(&page_desc, &pd, sizeof(PageDescriptor), false);
1434             if (ret < 0) {
1435                 error_setg(errp, "dump: failed to write page desc");
1436                 goto out;
1437             }
1438         }
1439         s->written_size += s->dump_info.page_size;
1440     }
1441 
1442     ret = write_cache(&page_desc, NULL, 0, true);
1443     if (ret < 0) {
1444         error_setg(errp, "dump: failed to sync cache for page_desc");
1445         goto out;
1446     }
1447     ret = write_cache(&page_data, NULL, 0, true);
1448     if (ret < 0) {
1449         error_setg(errp, "dump: failed to sync cache for page_data");
1450         goto out;
1451     }
1452 
1453 out:
1454     free_data_cache(&page_desc);
1455     free_data_cache(&page_data);
1456 
1457 #ifdef CONFIG_LZO
1458     g_free(wrkmem);
1459 #endif
1460 
1461     g_free(buf_out);
1462 }
1463 
1464 static void create_kdump_vmcore(DumpState *s, Error **errp)
1465 {
1466     int ret;
1467     Error *local_err = NULL;
1468 
1469     /*
1470      * the kdump-compressed format is:
1471      *                                               File offset
1472      *  +------------------------------------------+ 0x0
1473      *  |    main header (struct disk_dump_header) |
1474      *  |------------------------------------------+ block 1
1475      *  |    sub header (struct kdump_sub_header)  |
1476      *  |------------------------------------------+ block 2
1477      *  |            1st-dump_bitmap               |
1478      *  |------------------------------------------+ block 2 + X blocks
1479      *  |            2nd-dump_bitmap               | (aligned by block)
1480      *  |------------------------------------------+ block 2 + 2 * X blocks
1481      *  |  page desc for pfn 0 (struct page_desc)  | (aligned by block)
1482      *  |  page desc for pfn 1 (struct page_desc)  |
1483      *  |                    :                     |
1484      *  |------------------------------------------| (not aligned by block)
1485      *  |         page data (pfn 0)                |
1486      *  |         page data (pfn 1)                |
1487      *  |                    :                     |
1488      *  +------------------------------------------+
1489      */
1490 
1491     ret = write_start_flat_header(s->fd);
1492     if (ret < 0) {
1493         error_setg(errp, "dump: failed to write start flat header");
1494         return;
1495     }
1496 
1497     write_dump_header(s, &local_err);
1498     if (local_err) {
1499         error_propagate(errp, local_err);
1500         return;
1501     }
1502 
1503     write_dump_bitmap(s, &local_err);
1504     if (local_err) {
1505         error_propagate(errp, local_err);
1506         return;
1507     }
1508 
1509     write_dump_pages(s, &local_err);
1510     if (local_err) {
1511         error_propagate(errp, local_err);
1512         return;
1513     }
1514 
1515     ret = write_end_flat_header(s->fd);
1516     if (ret < 0) {
1517         error_setg(errp, "dump: failed to write end flat header");
1518         return;
1519     }
1520 }
1521 
1522 static ram_addr_t get_start_block(DumpState *s)
1523 {
1524     GuestPhysBlock *block;
1525 
1526     if (!s->has_filter) {
1527         s->next_block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
1528         return 0;
1529     }
1530 
1531     QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
1532         if (block->target_start >= s->begin + s->length ||
1533             block->target_end <= s->begin) {
1534             /* This block is out of the range */
1535             continue;
1536         }
1537 
1538         s->next_block = block;
1539         if (s->begin > block->target_start) {
1540             s->start = s->begin - block->target_start;
1541         } else {
1542             s->start = 0;
1543         }
1544         return s->start;
1545     }
1546 
1547     return -1;
1548 }
1549 
1550 static void get_max_mapnr(DumpState *s)
1551 {
1552     GuestPhysBlock *last_block;
1553 
1554     last_block = QTAILQ_LAST(&s->guest_phys_blocks.head);
1555     s->max_mapnr = dump_paddr_to_pfn(s, last_block->target_end);
1556 }
1557 
1558 static DumpState dump_state_global = { .status = DUMP_STATUS_NONE };
1559 
1560 static void dump_state_prepare(DumpState *s)
1561 {
1562     /* zero the struct, setting status to active */
1563     *s = (DumpState) { .status = DUMP_STATUS_ACTIVE };
1564 }
1565 
1566 bool qemu_system_dump_in_progress(void)
1567 {
1568     DumpState *state = &dump_state_global;
1569     return (qatomic_read(&state->status) == DUMP_STATUS_ACTIVE);
1570 }
1571 
1572 /* calculate total size of memory to be dumped (taking filter into
1573  * acoount.) */
1574 static int64_t dump_calculate_size(DumpState *s)
1575 {
1576     GuestPhysBlock *block;
1577     int64_t size = 0, total = 0, left = 0, right = 0;
1578 
1579     QTAILQ_FOREACH(block, &s->guest_phys_blocks.head, next) {
1580         if (s->has_filter) {
1581             /* calculate the overlapped region. */
1582             left = MAX(s->begin, block->target_start);
1583             right = MIN(s->begin + s->length, block->target_end);
1584             size = right - left;
1585             size = size > 0 ? size : 0;
1586         } else {
1587             /* count the whole region in */
1588             size = (block->target_end - block->target_start);
1589         }
1590         total += size;
1591     }
1592 
1593     return total;
1594 }
1595 
1596 static void vmcoreinfo_update_phys_base(DumpState *s)
1597 {
1598     uint64_t size, note_head_size, name_size, phys_base;
1599     char **lines;
1600     uint8_t *vmci;
1601     size_t i;
1602 
1603     if (!note_name_equal(s, s->guest_note, "VMCOREINFO")) {
1604         return;
1605     }
1606 
1607     get_note_sizes(s, s->guest_note, &note_head_size, &name_size, &size);
1608     note_head_size = ROUND_UP(note_head_size, 4);
1609 
1610     vmci = s->guest_note + note_head_size + ROUND_UP(name_size, 4);
1611     *(vmci + size) = '\0';
1612 
1613     lines = g_strsplit((char *)vmci, "\n", -1);
1614     for (i = 0; lines[i]; i++) {
1615         const char *prefix = NULL;
1616 
1617         if (s->dump_info.d_machine == EM_X86_64) {
1618             prefix = "NUMBER(phys_base)=";
1619         } else if (s->dump_info.d_machine == EM_AARCH64) {
1620             prefix = "NUMBER(PHYS_OFFSET)=";
1621         }
1622 
1623         if (prefix && g_str_has_prefix(lines[i], prefix)) {
1624             if (qemu_strtou64(lines[i] + strlen(prefix), NULL, 16,
1625                               &phys_base) < 0) {
1626                 warn_report("Failed to read %s", prefix);
1627             } else {
1628                 s->dump_info.phys_base = phys_base;
1629             }
1630             break;
1631         }
1632     }
1633 
1634     g_strfreev(lines);
1635 }
1636 
1637 static void dump_init(DumpState *s, int fd, bool has_format,
1638                       DumpGuestMemoryFormat format, bool paging, bool has_filter,
1639                       int64_t begin, int64_t length, Error **errp)
1640 {
1641     VMCoreInfoState *vmci = vmcoreinfo_find();
1642     CPUState *cpu;
1643     int nr_cpus;
1644     Error *err = NULL;
1645     int ret;
1646 
1647     s->has_format = has_format;
1648     s->format = format;
1649     s->written_size = 0;
1650 
1651     /* kdump-compressed is conflict with paging and filter */
1652     if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
1653         assert(!paging && !has_filter);
1654     }
1655 
1656     if (runstate_is_running()) {
1657         vm_stop(RUN_STATE_SAVE_VM);
1658         s->resume = true;
1659     } else {
1660         s->resume = false;
1661     }
1662 
1663     /* If we use KVM, we should synchronize the registers before we get dump
1664      * info or physmap info.
1665      */
1666     cpu_synchronize_all_states();
1667     nr_cpus = 0;
1668     CPU_FOREACH(cpu) {
1669         nr_cpus++;
1670     }
1671 
1672     s->fd = fd;
1673     s->has_filter = has_filter;
1674     s->begin = begin;
1675     s->length = length;
1676 
1677     memory_mapping_list_init(&s->list);
1678 
1679     guest_phys_blocks_init(&s->guest_phys_blocks);
1680     guest_phys_blocks_append(&s->guest_phys_blocks);
1681     s->total_size = dump_calculate_size(s);
1682 #ifdef DEBUG_DUMP_GUEST_MEMORY
1683     fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size);
1684 #endif
1685 
1686     /* it does not make sense to dump non-existent memory */
1687     if (!s->total_size) {
1688         error_setg(errp, "dump: no guest memory to dump");
1689         goto cleanup;
1690     }
1691 
1692     s->start = get_start_block(s);
1693     if (s->start == -1) {
1694         error_setg(errp, QERR_INVALID_PARAMETER, "begin");
1695         goto cleanup;
1696     }
1697 
1698     /* get dump info: endian, class and architecture.
1699      * If the target architecture is not supported, cpu_get_dump_info() will
1700      * return -1.
1701      */
1702     ret = cpu_get_dump_info(&s->dump_info, &s->guest_phys_blocks);
1703     if (ret < 0) {
1704         error_setg(errp, QERR_UNSUPPORTED);
1705         goto cleanup;
1706     }
1707 
1708     if (!s->dump_info.page_size) {
1709         s->dump_info.page_size = TARGET_PAGE_SIZE;
1710     }
1711 
1712     s->note_size = cpu_get_note_size(s->dump_info.d_class,
1713                                      s->dump_info.d_machine, nr_cpus);
1714     if (s->note_size < 0) {
1715         error_setg(errp, QERR_UNSUPPORTED);
1716         goto cleanup;
1717     }
1718 
1719     /*
1720      * The goal of this block is to (a) update the previously guessed
1721      * phys_base, (b) copy the guest note out of the guest.
1722      * Failure to do so is not fatal for dumping.
1723      */
1724     if (vmci) {
1725         uint64_t addr, note_head_size, name_size, desc_size;
1726         uint32_t size;
1727         uint16_t format;
1728 
1729         note_head_size = s->dump_info.d_class == ELFCLASS32 ?
1730             sizeof(Elf32_Nhdr) : sizeof(Elf64_Nhdr);
1731 
1732         format = le16_to_cpu(vmci->vmcoreinfo.guest_format);
1733         size = le32_to_cpu(vmci->vmcoreinfo.size);
1734         addr = le64_to_cpu(vmci->vmcoreinfo.paddr);
1735         if (!vmci->has_vmcoreinfo) {
1736             warn_report("guest note is not present");
1737         } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) {
1738             warn_report("guest note size is invalid: %" PRIu32, size);
1739         } else if (format != FW_CFG_VMCOREINFO_FORMAT_ELF) {
1740             warn_report("guest note format is unsupported: %" PRIu16, format);
1741         } else {
1742             s->guest_note = g_malloc(size + 1); /* +1 for adding \0 */
1743             cpu_physical_memory_read(addr, s->guest_note, size);
1744 
1745             get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size);
1746             s->guest_note_size = ELF_NOTE_SIZE(note_head_size, name_size,
1747                                                desc_size);
1748             if (name_size > MAX_GUEST_NOTE_SIZE ||
1749                 desc_size > MAX_GUEST_NOTE_SIZE ||
1750                 s->guest_note_size > size) {
1751                 warn_report("Invalid guest note header");
1752                 g_free(s->guest_note);
1753                 s->guest_note = NULL;
1754             } else {
1755                 vmcoreinfo_update_phys_base(s);
1756                 s->note_size += s->guest_note_size;
1757             }
1758         }
1759     }
1760 
1761     /* get memory mapping */
1762     if (paging) {
1763         qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, &err);
1764         if (err != NULL) {
1765             error_propagate(errp, err);
1766             goto cleanup;
1767         }
1768     } else {
1769         qemu_get_guest_simple_memory_mapping(&s->list, &s->guest_phys_blocks);
1770     }
1771 
1772     s->nr_cpus = nr_cpus;
1773 
1774     get_max_mapnr(s);
1775 
1776     uint64_t tmp;
1777     tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT),
1778                        s->dump_info.page_size);
1779     s->len_dump_bitmap = tmp * s->dump_info.page_size;
1780 
1781     /* init for kdump-compressed format */
1782     if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
1783         switch (format) {
1784         case DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB:
1785             s->flag_compress = DUMP_DH_COMPRESSED_ZLIB;
1786             break;
1787 
1788         case DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO:
1789 #ifdef CONFIG_LZO
1790             if (lzo_init() != LZO_E_OK) {
1791                 error_setg(errp, "failed to initialize the LZO library");
1792                 goto cleanup;
1793             }
1794 #endif
1795             s->flag_compress = DUMP_DH_COMPRESSED_LZO;
1796             break;
1797 
1798         case DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY:
1799             s->flag_compress = DUMP_DH_COMPRESSED_SNAPPY;
1800             break;
1801 
1802         default:
1803             s->flag_compress = 0;
1804         }
1805 
1806         return;
1807     }
1808 
1809     if (s->has_filter) {
1810         memory_mapping_filter(&s->list, s->begin, s->length);
1811     }
1812 
1813     /*
1814      * calculate phdr_num
1815      *
1816      * the type of ehdr->e_phnum is uint16_t, so we should avoid overflow
1817      */
1818     s->phdr_num = 1; /* PT_NOTE */
1819     if (s->list.num < UINT16_MAX - 2) {
1820         s->phdr_num += s->list.num;
1821         s->have_section = false;
1822     } else {
1823         s->have_section = true;
1824         s->phdr_num = PN_XNUM;
1825         s->sh_info = 1; /* PT_NOTE */
1826 
1827         /* the type of shdr->sh_info is uint32_t, so we should avoid overflow */
1828         if (s->list.num <= UINT32_MAX - 1) {
1829             s->sh_info += s->list.num;
1830         } else {
1831             s->sh_info = UINT32_MAX;
1832         }
1833     }
1834 
1835     if (s->dump_info.d_class == ELFCLASS64) {
1836         if (s->have_section) {
1837             s->memory_offset = sizeof(Elf64_Ehdr) +
1838                                sizeof(Elf64_Phdr) * s->sh_info +
1839                                sizeof(Elf64_Shdr) + s->note_size;
1840         } else {
1841             s->memory_offset = sizeof(Elf64_Ehdr) +
1842                                sizeof(Elf64_Phdr) * s->phdr_num + s->note_size;
1843         }
1844     } else {
1845         if (s->have_section) {
1846             s->memory_offset = sizeof(Elf32_Ehdr) +
1847                                sizeof(Elf32_Phdr) * s->sh_info +
1848                                sizeof(Elf32_Shdr) + s->note_size;
1849         } else {
1850             s->memory_offset = sizeof(Elf32_Ehdr) +
1851                                sizeof(Elf32_Phdr) * s->phdr_num + s->note_size;
1852         }
1853     }
1854 
1855     return;
1856 
1857 cleanup:
1858     dump_cleanup(s);
1859 }
1860 
1861 /* this operation might be time consuming. */
1862 static void dump_process(DumpState *s, Error **errp)
1863 {
1864     Error *local_err = NULL;
1865     DumpQueryResult *result = NULL;
1866 
1867     if (s->has_format && s->format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) {
1868 #ifdef TARGET_X86_64
1869         create_win_dump(s, &local_err);
1870 #endif
1871     } else if (s->has_format && s->format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
1872         create_kdump_vmcore(s, &local_err);
1873     } else {
1874         create_vmcore(s, &local_err);
1875     }
1876 
1877     /* make sure status is written after written_size updates */
1878     smp_wmb();
1879     qatomic_set(&s->status,
1880                (local_err ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED));
1881 
1882     /* send DUMP_COMPLETED message (unconditionally) */
1883     result = qmp_query_dump(NULL);
1884     /* should never fail */
1885     assert(result);
1886     qapi_event_send_dump_completed(result, !!local_err, (local_err ?
1887                                    error_get_pretty(local_err) : NULL));
1888     qapi_free_DumpQueryResult(result);
1889 
1890     error_propagate(errp, local_err);
1891     dump_cleanup(s);
1892 }
1893 
1894 static void *dump_thread(void *data)
1895 {
1896     DumpState *s = (DumpState *)data;
1897     dump_process(s, NULL);
1898     return NULL;
1899 }
1900 
1901 DumpQueryResult *qmp_query_dump(Error **errp)
1902 {
1903     DumpQueryResult *result = g_new(DumpQueryResult, 1);
1904     DumpState *state = &dump_state_global;
1905     result->status = qatomic_read(&state->status);
1906     /* make sure we are reading status and written_size in order */
1907     smp_rmb();
1908     result->completed = state->written_size;
1909     result->total = state->total_size;
1910     return result;
1911 }
1912 
1913 void qmp_dump_guest_memory(bool paging, const char *file,
1914                            bool has_detach, bool detach,
1915                            bool has_begin, int64_t begin, bool has_length,
1916                            int64_t length, bool has_format,
1917                            DumpGuestMemoryFormat format, Error **errp)
1918 {
1919     const char *p;
1920     int fd = -1;
1921     DumpState *s;
1922     Error *local_err = NULL;
1923     bool detach_p = false;
1924 
1925     if (runstate_check(RUN_STATE_INMIGRATE)) {
1926         error_setg(errp, "Dump not allowed during incoming migration.");
1927         return;
1928     }
1929 
1930     /* if there is a dump in background, we should wait until the dump
1931      * finished */
1932     if (qemu_system_dump_in_progress()) {
1933         error_setg(errp, "There is a dump in process, please wait.");
1934         return;
1935     }
1936 
1937     /*
1938      * kdump-compressed format need the whole memory dumped, so paging or
1939      * filter is not supported here.
1940      */
1941     if ((has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) &&
1942         (paging || has_begin || has_length)) {
1943         error_setg(errp, "kdump-compressed format doesn't support paging or "
1944                          "filter");
1945         return;
1946     }
1947     if (has_begin && !has_length) {
1948         error_setg(errp, QERR_MISSING_PARAMETER, "length");
1949         return;
1950     }
1951     if (!has_begin && has_length) {
1952         error_setg(errp, QERR_MISSING_PARAMETER, "begin");
1953         return;
1954     }
1955     if (has_detach) {
1956         detach_p = detach;
1957     }
1958 
1959     /* check whether lzo/snappy is supported */
1960 #ifndef CONFIG_LZO
1961     if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO) {
1962         error_setg(errp, "kdump-lzo is not available now");
1963         return;
1964     }
1965 #endif
1966 
1967 #ifndef CONFIG_SNAPPY
1968     if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY) {
1969         error_setg(errp, "kdump-snappy is not available now");
1970         return;
1971     }
1972 #endif
1973 
1974 #ifndef TARGET_X86_64
1975     if (has_format && format == DUMP_GUEST_MEMORY_FORMAT_WIN_DMP) {
1976         error_setg(errp, "Windows dump is only available for x86-64");
1977         return;
1978     }
1979 #endif
1980 
1981 #if !defined(WIN32)
1982     if (strstart(file, "fd:", &p)) {
1983         fd = monitor_get_fd(monitor_cur(), p, errp);
1984         if (fd == -1) {
1985             return;
1986         }
1987     }
1988 #endif
1989 
1990     if  (strstart(file, "file:", &p)) {
1991         fd = qemu_open_old(p, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR);
1992         if (fd < 0) {
1993             error_setg_file_open(errp, errno, p);
1994             return;
1995         }
1996     }
1997 
1998     if (fd == -1) {
1999         error_setg(errp, QERR_INVALID_PARAMETER, "protocol");
2000         return;
2001     }
2002 
2003     if (!dump_migration_blocker) {
2004         error_setg(&dump_migration_blocker,
2005                    "Live migration disabled: dump-guest-memory in progress");
2006     }
2007 
2008     /*
2009      * Allows even for -only-migratable, but forbid migration during the
2010      * process of dump guest memory.
2011      */
2012     if (migrate_add_blocker_internal(dump_migration_blocker, errp)) {
2013         /* Remember to release the fd before passing it over to dump state */
2014         close(fd);
2015         return;
2016     }
2017 
2018     s = &dump_state_global;
2019     dump_state_prepare(s);
2020 
2021     dump_init(s, fd, has_format, format, paging, has_begin,
2022               begin, length, &local_err);
2023     if (local_err) {
2024         error_propagate(errp, local_err);
2025         qatomic_set(&s->status, DUMP_STATUS_FAILED);
2026         return;
2027     }
2028 
2029     if (detach_p) {
2030         /* detached dump */
2031         s->detached = true;
2032         qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread,
2033                            s, QEMU_THREAD_DETACHED);
2034     } else {
2035         /* sync dump */
2036         dump_process(s, errp);
2037     }
2038 }
2039 
2040 DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp)
2041 {
2042     DumpGuestMemoryCapability *cap =
2043                                   g_new0(DumpGuestMemoryCapability, 1);
2044     DumpGuestMemoryFormatList **tail = &cap->formats;
2045 
2046     /* elf is always available */
2047     QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_ELF);
2048 
2049     /* kdump-zlib is always available */
2050     QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB);
2051 
2052     /* add new item if kdump-lzo is available */
2053 #ifdef CONFIG_LZO
2054     QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO);
2055 #endif
2056 
2057     /* add new item if kdump-snappy is available */
2058 #ifdef CONFIG_SNAPPY
2059     QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY);
2060 #endif
2061 
2062     /* Windows dump is available only if target is x86_64 */
2063 #ifdef TARGET_X86_64
2064     QAPI_LIST_APPEND(tail, DUMP_GUEST_MEMORY_FORMAT_WIN_DMP);
2065 #endif
2066 
2067     return cap;
2068 }
2069