2 * Copyright (c) 2002 Marcel Moolenaar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include "opt_watchdog.h"
32 #include <sys/param.h>
33 #include <sys/systm.h>
36 #include <sys/sysctl.h>
37 #include <sys/kernel.h>
38 #include <sys/kerneldump.h>
40 #include <sys/watchdog.h>
44 #include <machine/elf.h>
45 #include <machine/md_var.h>
48 #define KERNELDUMP_VERSION KERNELDUMP_AMD64_VERSION
49 #define EM_VALUE EM_X86_64
51 #define KERNELDUMP_VERSION KERNELDUMP_I386_VERSION
52 #define EM_VALUE EM_386
55 CTASSERT(sizeof(struct kerneldumpheader) == 512);
58 TUNABLE_INT("debug.minidump", &do_minidump);
59 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0,
60 "Enable mini crash dumps");
63 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
64 * is to protect us from metadata and to protect metadata from us.
66 #define SIZEOF_METADATA (64*1024)
68 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
69 #define DEV_ALIGN(x) (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
76 typedef int callback_t(struct md_pa *, int, void *);
78 static struct kerneldumpheader kdh;
79 static off_t dumplo, fileofs;
81 /* Handle buffered writes. */
82 static char buffer[DEV_BSIZE];
85 /* 20 phys_avail entry pairs correspond to 10 md_pa's */
86 static struct md_pa dump_map[10];
93 bzero(dump_map, sizeof(dump_map));
94 for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) {
96 if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
98 dump_map[n].md_start = dump_avail[idx];
99 dump_map[n].md_size = dump_avail[idx + 1] - dump_avail[idx];
103 static struct md_pa *
107 return (&dump_map[0]);
110 static struct md_pa *
111 md_pa_next(struct md_pa *mdp)
115 if (mdp->md_size == 0)
121 buf_write(struct dumperinfo *di, char *ptr, size_t sz)
127 len = DEV_BSIZE - fragsz;
130 bcopy(ptr, buffer + fragsz, len);
134 if (fragsz == DEV_BSIZE) {
135 error = dump_write(di, buffer, 0, dumplo,
148 buf_flush(struct dumperinfo *di)
155 error = dump_write(di, buffer, 0, dumplo, DEV_BSIZE);
161 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8)
164 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg)
166 struct dumperinfo *di = (struct dumperinfo*)arg;
170 size_t counter, sz, chunk;
171 int i, c, error, twiddle;
174 error = 0; /* catch case in which chunk size is 0 */
175 counter = 0; /* Update twiddle every 16MB */
178 pgs = mdp->md_size / PAGE_SIZE;
180 maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
181 if (maxdumppgs == 0) /* seatbelt */
184 printf(" chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
189 if (chunk > maxdumppgs)
191 sz = chunk << PAGE_SHIFT;
194 printf(" %ju", (uintmax_t)PG2MB(pgs));
195 counter &= (1<<24) - 1;
197 for (i = 0; i < chunk; i++) {
198 a = pa + i * PAGE_SIZE;
199 va = pmap_kenter_temporary(trunc_page(a), i);
202 wdog_kern_pat(WD_LASTVAL);
204 error = dump_write(di, va, 0, dumplo, sz);
211 /* Check for user abort. */
216 printf(" (CTRL-C to abort) ");
218 printf(" ... %s\n", (error) ? "fail" : "ok");
223 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg)
225 struct dumperinfo *di = (struct dumperinfo*)arg;
231 bzero(&phdr, sizeof(phdr));
232 phdr.p_type = PT_LOAD;
233 phdr.p_flags = PF_R; /* XXX */
234 phdr.p_offset = fileofs;
235 phdr.p_vaddr = mdp->md_start;
236 phdr.p_paddr = mdp->md_start;
237 phdr.p_filesz = size;
239 phdr.p_align = PAGE_SIZE;
241 error = buf_write(di, (char*)&phdr, sizeof(phdr));
242 fileofs += phdr.p_filesz;
247 cb_size(struct md_pa *mdp, int seqnr, void *arg)
249 uint64_t *sz = (uint64_t*)arg;
251 *sz += (uint64_t)mdp->md_size;
256 foreach_chunk(callback_t cb, void *arg)
263 while (mdp != NULL) {
264 error = (*cb)(mdp, seqnr++, arg);
267 mdp = md_pa_next(mdp);
273 dumpsys(struct dumperinfo *di)
285 bzero(&ehdr, sizeof(ehdr));
286 ehdr.e_ident[EI_MAG0] = ELFMAG0;
287 ehdr.e_ident[EI_MAG1] = ELFMAG1;
288 ehdr.e_ident[EI_MAG2] = ELFMAG2;
289 ehdr.e_ident[EI_MAG3] = ELFMAG3;
290 ehdr.e_ident[EI_CLASS] = ELF_CLASS;
291 #if BYTE_ORDER == LITTLE_ENDIAN
292 ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
294 ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
296 ehdr.e_ident[EI_VERSION] = EV_CURRENT;
297 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */
298 ehdr.e_type = ET_CORE;
299 ehdr.e_machine = EM_VALUE;
300 ehdr.e_phoff = sizeof(ehdr);
302 ehdr.e_ehsize = sizeof(ehdr);
303 ehdr.e_phentsize = sizeof(Elf_Phdr);
304 ehdr.e_shentsize = sizeof(Elf_Shdr);
308 /* Calculate dump size. */
310 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize);
311 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
312 fileofs = MD_ALIGN(hdrsz);
314 hdrgap = fileofs - DEV_ALIGN(hdrsz);
316 /* Determine dump offset on device. */
317 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
321 dumplo = di->mediaoffset + di->mediasize - dumpsize;
322 dumplo -= sizeof(kdh) * 2;
324 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_VERSION, dumpsize,
327 printf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20,
331 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
334 dumplo += sizeof(kdh);
336 /* Dump ELF header */
337 error = buf_write(di, (char*)&ehdr, sizeof(ehdr));
341 /* Dump program headers */
342 error = foreach_chunk(cb_dumphdr, di);
348 * All headers are written using blocked I/O, so we know the
349 * current offset is (still) block aligned. Skip the alignement
350 * in the file to have the segment contents aligned at page
351 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
352 * care and may very well be unaligned within the dump device.
356 /* Dump memory chunks (updates dumplo) */
357 error = foreach_chunk(cb_dumpdata, di);
362 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
366 /* Signal completion, signoff and exit stage left. */
367 dump_write(di, NULL, 0, 0, 0);
368 printf("\nDump complete\n");
375 if (error == ECANCELED)
376 printf("\nDump aborted\n");
377 else if (error == ENOSPC)
378 printf("\nDump failed. Partition too small.\n");
380 printf("\n** DUMP FAILED (ERROR %d) **\n", error);