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 <sys/param.h>
31 #include <sys/systm.h>
34 #include <sys/sysctl.h>
35 #include <sys/kernel.h>
36 #include <sys/kerneldump.h>
39 #include <machine/elf.h>
40 #include <machine/md_var.h>
43 #define KERNELDUMP_VERSION KERNELDUMP_AMD64_VERSION
44 #define EM_VALUE EM_X86_64
46 #define KERNELDUMP_VERSION KERNELDUMP_I386_VERSION
47 #define EM_VALUE EM_386
50 CTASSERT(sizeof(struct kerneldumpheader) == 512);
53 TUNABLE_INT("debug.minidump", &do_minidump);
54 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0,
55 "Enable mini crash dumps");
58 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
59 * is to protect us from metadata and to protect metadata from us.
61 #define SIZEOF_METADATA (64*1024)
63 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
64 #define DEV_ALIGN(x) (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
71 typedef int callback_t(struct md_pa *, int, void *);
73 static struct kerneldumpheader kdh;
74 static off_t dumplo, fileofs;
76 /* Handle buffered writes. */
77 static char buffer[DEV_BSIZE];
80 /* 20 phys_avail entry pairs correspond to 10 md_pa's */
81 static struct md_pa dump_map[10];
88 bzero(dump_map, sizeof(dump_map));
89 for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) {
91 if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
93 dump_map[n].md_start = dump_avail[idx];
94 dump_map[n].md_size = dump_avail[idx + 1] - dump_avail[idx];
102 return (&dump_map[0]);
105 static struct md_pa *
106 md_pa_next(struct md_pa *mdp)
110 if (mdp->md_size == 0)
116 buf_write(struct dumperinfo *di, char *ptr, size_t sz)
122 len = DEV_BSIZE - fragsz;
125 bcopy(ptr, buffer + fragsz, len);
129 if (fragsz == DEV_BSIZE) {
130 error = dump_write(di, buffer, 0, dumplo,
143 buf_flush(struct dumperinfo *di)
150 error = dump_write(di, buffer, 0, dumplo, DEV_BSIZE);
156 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8)
159 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg)
161 struct dumperinfo *di = (struct dumperinfo*)arg;
165 size_t counter, sz, chunk;
166 int i, c, error, twiddle;
169 error = 0; /* catch case in which chunk size is 0 */
170 counter = 0; /* Update twiddle every 16MB */
173 pgs = mdp->md_size / PAGE_SIZE;
175 maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
176 if (maxdumppgs == 0) /* seatbelt */
179 printf(" chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
184 if (chunk > maxdumppgs)
186 sz = chunk << PAGE_SHIFT;
189 printf(" %ju", (uintmax_t)PG2MB(pgs));
190 counter &= (1<<24) - 1;
192 for (i = 0; i < chunk; i++) {
193 a = pa + i * PAGE_SIZE;
194 va = pmap_kenter_temporary(trunc_page(a), i);
196 error = dump_write(di, va, 0, dumplo, sz);
203 /* Check for user abort. */
208 printf(" (CTRL-C to abort) ");
210 printf(" ... %s\n", (error) ? "fail" : "ok");
215 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg)
217 struct dumperinfo *di = (struct dumperinfo*)arg;
223 bzero(&phdr, sizeof(phdr));
224 phdr.p_type = PT_LOAD;
225 phdr.p_flags = PF_R; /* XXX */
226 phdr.p_offset = fileofs;
227 phdr.p_vaddr = mdp->md_start;
228 phdr.p_paddr = mdp->md_start;
229 phdr.p_filesz = size;
231 phdr.p_align = PAGE_SIZE;
233 error = buf_write(di, (char*)&phdr, sizeof(phdr));
234 fileofs += phdr.p_filesz;
239 cb_size(struct md_pa *mdp, int seqnr, void *arg)
241 uint64_t *sz = (uint64_t*)arg;
243 *sz += (uint64_t)mdp->md_size;
248 foreach_chunk(callback_t cb, void *arg)
255 while (mdp != NULL) {
256 error = (*cb)(mdp, seqnr++, arg);
259 mdp = md_pa_next(mdp);
265 dumpsys(struct dumperinfo *di)
277 bzero(&ehdr, sizeof(ehdr));
278 ehdr.e_ident[EI_MAG0] = ELFMAG0;
279 ehdr.e_ident[EI_MAG1] = ELFMAG1;
280 ehdr.e_ident[EI_MAG2] = ELFMAG2;
281 ehdr.e_ident[EI_MAG3] = ELFMAG3;
282 ehdr.e_ident[EI_CLASS] = ELF_CLASS;
283 #if BYTE_ORDER == LITTLE_ENDIAN
284 ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
286 ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
288 ehdr.e_ident[EI_VERSION] = EV_CURRENT;
289 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */
290 ehdr.e_type = ET_CORE;
291 ehdr.e_machine = EM_VALUE;
292 ehdr.e_phoff = sizeof(ehdr);
294 ehdr.e_ehsize = sizeof(ehdr);
295 ehdr.e_phentsize = sizeof(Elf_Phdr);
296 ehdr.e_shentsize = sizeof(Elf_Shdr);
300 /* Calculate dump size. */
302 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize);
303 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
304 fileofs = MD_ALIGN(hdrsz);
306 hdrgap = fileofs - DEV_ALIGN(hdrsz);
308 /* Determine dump offset on device. */
309 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
313 dumplo = di->mediaoffset + di->mediasize - dumpsize;
314 dumplo -= sizeof(kdh) * 2;
316 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_VERSION, dumpsize,
319 printf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20,
323 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
326 dumplo += sizeof(kdh);
328 /* Dump ELF header */
329 error = buf_write(di, (char*)&ehdr, sizeof(ehdr));
333 /* Dump program headers */
334 error = foreach_chunk(cb_dumphdr, di);
340 * All headers are written using blocked I/O, so we know the
341 * current offset is (still) block aligned. Skip the alignement
342 * in the file to have the segment contents aligned at page
343 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
344 * care and may very well be unaligned within the dump device.
348 /* Dump memory chunks (updates dumplo) */
349 error = foreach_chunk(cb_dumpdata, di);
354 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
358 /* Signal completion, signoff and exit stage left. */
359 dump_write(di, NULL, 0, 0, 0);
360 printf("\nDump complete\n");
367 if (error == ECANCELED)
368 printf("\nDump aborted\n");
369 else if (error == ENOSPC)
370 printf("\nDump failed. Partition too small.\n");
372 printf("\n** DUMP FAILED (ERROR %d) **\n", error);