1 /*-
2 * Copyright (c) 2002 Marcel Moolenaar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/conf.h>
30 #include <sys/cons.h>
31 #include <sys/kdb.h>
32 #include <sys/kernel.h>
33 #include <sys/kerneldump.h>
34 #include <sys/malloc.h>
35 #include <sys/msgbuf.h>
36 #include <sys/proc.h>
37 #include <sys/watchdog.h>
38
39 #include <vm/vm.h>
40 #include <vm/vm_param.h>
41 #include <vm/vm_page.h>
42 #include <vm/vm_phys.h>
43 #include <vm/vm_dumpset.h>
44 #include <vm/pmap.h>
45
46 #include <machine/dump.h>
47 #include <machine/elf.h>
48 #include <machine/md_var.h>
49 #include <machine/pcb.h>
50
51 CTASSERT(sizeof(struct kerneldumpheader) == 512);
52
53 #define MD_ALIGN(x) roundup2((off_t)(x), PAGE_SIZE)
54
55 /* Handle buffered writes. */
56 static size_t fragsz;
57
58 struct dump_pa dump_map[DUMPSYS_MD_PA_NPAIRS];
59
60 #if !defined(__powerpc__)
61 void
dumpsys_gen_pa_init(void)62 dumpsys_gen_pa_init(void)
63 {
64 int n, idx;
65
66 bzero(dump_map, sizeof(dump_map));
67 for (n = 0; n < nitems(dump_map); n++) {
68 idx = n * 2;
69 if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
70 break;
71 dump_map[n].pa_start = dump_avail[idx];
72 dump_map[n].pa_size = dump_avail[idx + 1] - dump_avail[idx];
73 }
74 }
75 #endif
76
77 struct dump_pa *
dumpsys_gen_pa_next(struct dump_pa * mdp)78 dumpsys_gen_pa_next(struct dump_pa *mdp)
79 {
80
81 if (mdp == NULL)
82 return (&dump_map[0]);
83
84 mdp++;
85 if (mdp - dump_map >= nitems(dump_map) ||
86 (mdp->pa_start == 0 && mdp->pa_size == 0))
87 mdp = NULL;
88 return (mdp);
89 }
90
91 void
dumpsys_gen_wbinv_all(void)92 dumpsys_gen_wbinv_all(void)
93 {
94
95 }
96
97 void
dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused,size_t chunk __unused,void * va __unused)98 dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused, size_t chunk __unused,
99 void *va __unused)
100 {
101
102 }
103
104 int
dumpsys_gen_write_aux_headers(struct dumperinfo * di)105 dumpsys_gen_write_aux_headers(struct dumperinfo *di)
106 {
107
108 return (0);
109 }
110
111 int
dumpsys_buf_seek(struct dumperinfo * di,size_t sz)112 dumpsys_buf_seek(struct dumperinfo *di, size_t sz)
113 {
114 static uint8_t buf[DEV_BSIZE];
115 size_t nbytes;
116 int error;
117
118 bzero(buf, sizeof(buf));
119
120 while (sz > 0) {
121 nbytes = MIN(sz, sizeof(buf));
122
123 error = dump_append(di, buf, nbytes);
124 if (error)
125 return (error);
126 sz -= nbytes;
127 }
128
129 return (0);
130 }
131
132 int
dumpsys_buf_write(struct dumperinfo * di,char * ptr,size_t sz)133 dumpsys_buf_write(struct dumperinfo *di, char *ptr, size_t sz)
134 {
135 size_t len;
136 int error;
137
138 while (sz) {
139 len = di->blocksize - fragsz;
140 if (len > sz)
141 len = sz;
142 memcpy((char *)di->blockbuf + fragsz, ptr, len);
143 fragsz += len;
144 ptr += len;
145 sz -= len;
146 if (fragsz == di->blocksize) {
147 error = dump_append(di, di->blockbuf, di->blocksize);
148 if (error)
149 return (error);
150 fragsz = 0;
151 }
152 }
153 return (0);
154 }
155
156 int
dumpsys_buf_flush(struct dumperinfo * di)157 dumpsys_buf_flush(struct dumperinfo *di)
158 {
159 int error;
160
161 if (fragsz == 0)
162 return (0);
163
164 error = dump_append(di, di->blockbuf, di->blocksize);
165 fragsz = 0;
166 return (error);
167 }
168
169 CTASSERT(PAGE_SHIFT < 20);
170 #define PG2MB(pgs) ((pgs + (1 << (20 - PAGE_SHIFT)) - 1) >> (20 - PAGE_SHIFT))
171
172 int
dumpsys_cb_dumpdata(struct dump_pa * mdp,int seqnr,void * arg)173 dumpsys_cb_dumpdata(struct dump_pa *mdp, int seqnr, void *arg)
174 {
175 struct dumperinfo *di = (struct dumperinfo*)arg;
176 vm_paddr_t pa;
177 void *va;
178 uint64_t pgs;
179 size_t counter, sz, chunk;
180 int c, error;
181 u_int maxdumppgs;
182
183 error = 0; /* catch case in which chunk size is 0 */
184 counter = 0; /* Update twiddle every 16MB */
185 va = NULL;
186 pgs = mdp->pa_size / PAGE_SIZE;
187 pa = mdp->pa_start;
188 maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
189 if (maxdumppgs == 0) /* seatbelt */
190 maxdumppgs = 1;
191
192 printf(" chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
193 (uintmax_t)pgs);
194
195 dumpsys_wbinv_all();
196 while (pgs) {
197 chunk = pgs;
198 if (chunk > maxdumppgs)
199 chunk = maxdumppgs;
200 sz = chunk << PAGE_SHIFT;
201 counter += sz;
202 if (counter >> 24) {
203 printf(" %ju", (uintmax_t)PG2MB(pgs));
204 counter &= (1 << 24) - 1;
205 }
206
207 dumpsys_map_chunk(pa, chunk, &va);
208 wdog_kern_pat(WD_LASTVAL);
209
210 error = dump_append(di, va, sz);
211 dumpsys_unmap_chunk(pa, chunk, va);
212 if (error)
213 break;
214 pgs -= chunk;
215 pa += sz;
216
217 /* Check for user abort. */
218 c = cncheckc();
219 if (c == 0x03)
220 return (ECANCELED);
221 if (c != -1)
222 printf(" (CTRL-C to abort) ");
223 }
224 printf(" ... %s\n", (error) ? "fail" : "ok");
225 return (error);
226 }
227
228 int
dumpsys_foreach_chunk(dumpsys_callback_t cb,void * arg)229 dumpsys_foreach_chunk(dumpsys_callback_t cb, void *arg)
230 {
231 struct dump_pa *mdp;
232 int error, seqnr;
233
234 seqnr = 0;
235 mdp = dumpsys_pa_next(NULL);
236 while (mdp != NULL) {
237 error = (*cb)(mdp, seqnr++, arg);
238 if (error)
239 return (-error);
240 mdp = dumpsys_pa_next(mdp);
241 }
242 return (seqnr);
243 }
244
245 static off_t fileofs;
246
247 static int
cb_dumphdr(struct dump_pa * mdp,int seqnr,void * arg)248 cb_dumphdr(struct dump_pa *mdp, int seqnr, void *arg)
249 {
250 struct dumperinfo *di = (struct dumperinfo*)arg;
251 Elf_Phdr phdr;
252 uint64_t size;
253 int error;
254
255 size = mdp->pa_size;
256 bzero(&phdr, sizeof(phdr));
257 phdr.p_type = PT_LOAD;
258 phdr.p_flags = PF_R; /* XXX */
259 phdr.p_offset = fileofs;
260 #ifdef __powerpc__
261 phdr.p_vaddr = (do_minidump? mdp->pa_start : ~0L);
262 phdr.p_paddr = (do_minidump? ~0L : mdp->pa_start);
263 #else
264 phdr.p_vaddr = mdp->pa_start;
265 phdr.p_paddr = mdp->pa_start;
266 #endif
267 phdr.p_filesz = size;
268 phdr.p_memsz = size;
269 phdr.p_align = PAGE_SIZE;
270
271 error = dumpsys_buf_write(di, (char*)&phdr, sizeof(phdr));
272 fileofs += phdr.p_filesz;
273 return (error);
274 }
275
276 static int
cb_size(struct dump_pa * mdp,int seqnr,void * arg)277 cb_size(struct dump_pa *mdp, int seqnr, void *arg)
278 {
279 uint64_t *sz;
280
281 sz = (uint64_t *)arg;
282 *sz += (uint64_t)mdp->pa_size;
283 return (0);
284 }
285
286 int
dumpsys_generic(struct dumperinfo * di)287 dumpsys_generic(struct dumperinfo *di)
288 {
289 static struct kerneldumpheader kdh;
290 Elf_Ehdr ehdr;
291 uint64_t dumpsize;
292 off_t hdrgap;
293 size_t hdrsz;
294 int error;
295
296 #if MINIDUMP_PAGE_TRACKING == 1
297 if (do_minidump)
298 return (minidumpsys(di, false));
299 #endif
300
301 bzero(&ehdr, sizeof(ehdr));
302 ehdr.e_ident[EI_MAG0] = ELFMAG0;
303 ehdr.e_ident[EI_MAG1] = ELFMAG1;
304 ehdr.e_ident[EI_MAG2] = ELFMAG2;
305 ehdr.e_ident[EI_MAG3] = ELFMAG3;
306 ehdr.e_ident[EI_CLASS] = ELF_CLASS;
307 #if BYTE_ORDER == LITTLE_ENDIAN
308 ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
309 #else
310 ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
311 #endif
312 ehdr.e_ident[EI_VERSION] = EV_CURRENT;
313 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */
314 ehdr.e_type = ET_CORE;
315 ehdr.e_machine = EM_VALUE;
316 ehdr.e_phoff = sizeof(ehdr);
317 ehdr.e_flags = 0;
318 ehdr.e_ehsize = sizeof(ehdr);
319 ehdr.e_phentsize = sizeof(Elf_Phdr);
320 ehdr.e_shentsize = sizeof(Elf_Shdr);
321
322 dumpsys_pa_init();
323
324 /* Calculate dump size. */
325 dumpsize = 0L;
326 ehdr.e_phnum = dumpsys_foreach_chunk(cb_size, &dumpsize) +
327 DUMPSYS_NUM_AUX_HDRS;
328 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
329 fileofs = MD_ALIGN(hdrsz);
330 dumpsize += fileofs;
331 hdrgap = fileofs - roundup2((off_t)hdrsz, di->blocksize);
332
333 dump_init_header(di, &kdh, KERNELDUMPMAGIC, KERNELDUMP_ARCH_VERSION,
334 dumpsize);
335
336 error = dump_start(di, &kdh);
337 if (error != 0)
338 goto fail;
339
340 printf("Dumping %ju MB (%d chunks)\n", (uintmax_t)dumpsize >> 20,
341 ehdr.e_phnum - DUMPSYS_NUM_AUX_HDRS);
342
343 /* Dump ELF header */
344 error = dumpsys_buf_write(di, (char*)&ehdr, sizeof(ehdr));
345 if (error)
346 goto fail;
347
348 /* Dump program headers */
349 error = dumpsys_foreach_chunk(cb_dumphdr, di);
350 if (error < 0)
351 goto fail;
352 error = dumpsys_write_aux_headers(di);
353 if (error < 0)
354 goto fail;
355 dumpsys_buf_flush(di);
356
357 /*
358 * All headers are written using blocked I/O, so we know the
359 * current offset is (still) block aligned. Skip the alignement
360 * in the file to have the segment contents aligned at page
361 * boundary.
362 */
363 error = dumpsys_buf_seek(di, (size_t)hdrgap);
364 if (error)
365 goto fail;
366
367 /* Dump memory chunks. */
368 error = dumpsys_foreach_chunk(dumpsys_cb_dumpdata, di);
369 if (error < 0)
370 goto fail;
371
372 error = dump_finish(di, &kdh);
373 if (error != 0)
374 goto fail;
375
376 printf("\nDump complete\n");
377 return (0);
378
379 fail:
380 if (error < 0)
381 error = -error;
382
383 if (error == ECANCELED)
384 printf("\nDump aborted\n");
385 else if (error == E2BIG || error == ENOSPC)
386 printf("\nDump failed. Partition too small.\n");
387 else
388 printf("\n** DUMP FAILED (ERROR %d) **\n", error);
389 return (error);
390 }
391
392 #if MINIDUMP_PAGE_TRACKING == 1
393
394 /* Minidump progress bar */
395 static struct {
396 const int min_per;
397 const int max_per;
398 bool visited;
399 } progress_track[10] = {
400 { 0, 10, false},
401 { 10, 20, false},
402 { 20, 30, false},
403 { 30, 40, false},
404 { 40, 50, false},
405 { 50, 60, false},
406 { 60, 70, false},
407 { 70, 80, false},
408 { 80, 90, false},
409 { 90, 100, false}
410 };
411
412 static uint64_t dumpsys_pb_size;
413 static uint64_t dumpsys_pb_remaining;
414 static uint64_t dumpsys_pb_check;
415
416 /* Reset the progress bar for a dump of dumpsize. */
417 void
dumpsys_pb_init(uint64_t dumpsize)418 dumpsys_pb_init(uint64_t dumpsize)
419 {
420 int i;
421
422 dumpsys_pb_size = dumpsys_pb_remaining = dumpsize;
423 dumpsys_pb_check = 0;
424
425 for (i = 0; i < nitems(progress_track); i++)
426 progress_track[i].visited = false;
427 }
428
429 /*
430 * Update the progress according to the delta bytes that were written out.
431 * Check and print the progress percentage.
432 */
433 void
dumpsys_pb_progress(size_t delta)434 dumpsys_pb_progress(size_t delta)
435 {
436 int sofar, i;
437
438 dumpsys_pb_remaining -= delta;
439 dumpsys_pb_check += delta;
440
441 /*
442 * To save time while dumping, only loop through progress_track
443 * occasionally.
444 */
445 if ((dumpsys_pb_check >> DUMPSYS_PB_CHECK_BITS) == 0)
446 return;
447 else
448 dumpsys_pb_check &= (1 << DUMPSYS_PB_CHECK_BITS) - 1;
449
450 sofar = 100 - ((dumpsys_pb_remaining * 100) / dumpsys_pb_size);
451 for (i = 0; i < nitems(progress_track); i++) {
452 if (sofar < progress_track[i].min_per ||
453 sofar > progress_track[i].max_per)
454 continue;
455 if (!progress_track[i].visited) {
456 progress_track[i].visited = true;
457 printf("..%d%%", sofar);
458 }
459 break;
460 }
461 }
462
463 int
minidumpsys(struct dumperinfo * di,bool livedump)464 minidumpsys(struct dumperinfo *di, bool livedump)
465 {
466 struct minidumpstate state;
467 struct msgbuf mb_copy;
468 char *msg_ptr;
469 int error;
470
471 if (livedump) {
472 KASSERT(!dumping, ("live dump invoked from incorrect context"));
473
474 /*
475 * Before invoking cpu_minidumpsys() on the live system, we
476 * must snapshot some required global state: the message
477 * buffer, and the page dump bitset. They may be modified at
478 * any moment, so for the sake of the live dump it is best to
479 * have an unchanging snapshot to work with. Both are included
480 * as part of the dump and consumed by userspace tools.
481 *
482 * Other global state important to the minidump code is the
483 * dump_avail array and the kernel's page tables, but snapshots
484 * are not taken of these. For one, dump_avail[] is expected
485 * not to change after boot. Snapshotting the kernel page
486 * tables would involve an additional walk, so this is avoided
487 * too.
488 *
489 * This means live dumps are best effort, and the result may or
490 * may not be usable; there are no guarantees about the
491 * consistency of the dump's contents. Any of the following
492 * (and likely more) may affect the live dump:
493 *
494 * - Data may be modified, freed, or remapped during the
495 * course of the dump, such that the contents written out
496 * are partially or entirely unrecognizable. This means
497 * valid references may point to destroyed/mangled objects,
498 * and vice versa.
499 *
500 * - The dumped context of any threads that ran during the
501 * dump process may be unreliable.
502 *
503 * - The set of kernel page tables included in the dump likely
504 * won't correspond exactly to the copy of the dump bitset.
505 * This means some pages will be dumped without any way to
506 * locate them, and some pages may not have been dumped
507 * despite appearing as if they should.
508 */
509 msg_ptr = malloc(msgbufsize, M_TEMP, M_WAITOK);
510 msgbuf_duplicate(msgbufp, &mb_copy, msg_ptr);
511 state.msgbufp = &mb_copy;
512
513 state.dump_bitset = BITSET_ALLOC(vm_page_dump_pages, M_TEMP,
514 M_WAITOK);
515 BIT_COPY_STORE_REL(vm_page_dump_pages, vm_page_dump,
516 state.dump_bitset);
517 } else {
518 KASSERT(dumping, ("minidump invoked outside of doadump()"));
519
520 /* Use the globals. */
521 state.msgbufp = msgbufp;
522 state.dump_bitset = vm_page_dump;
523 }
524
525 error = cpu_minidumpsys(di, &state);
526 if (livedump) {
527 free(msg_ptr, M_TEMP);
528 BITSET_FREE(state.dump_bitset, M_TEMP);
529 }
530
531 return (error);
532 }
533 #endif /* MINIDUMP_PAGE_TRACKING == 1 */
534