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/cdefs.h>
28 __FBSDID("$FreeBSD: src/sys/amd64/amd64/dump_machdep.c,v 1.17 2008/10/31 10:11:35 kib Exp $");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/conf.h>
33 #include <sys/cons.h>
34 #include <sys/sysctl.h>
35 #include <sys/kernel.h>
36 #include <sys/kerneldump.h>
37 #include <sys/vimage.h>
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 #include <machine/elf.h>
41 #include <machine/md_var.h>
42
43 CTASSERT(sizeof(struct kerneldumpheader) == 512);
44
45 int do_minidump = 1;
46 TUNABLE_INT("debug.minidump", &do_minidump);
47 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0,
48 "Enable mini crash dumps");
49
50 /*
51 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
52 * is to protect us from metadata and to protect metadata from us.
53 */
54 #define SIZEOF_METADATA (64*1024)
55
56 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
57 #define DEV_ALIGN(x) (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
58
59 struct md_pa {
60 vm_paddr_t md_start;
61 vm_paddr_t md_size;
62 };
63
64 typedef int callback_t(struct md_pa *, int, void *);
65
66 static struct kerneldumpheader kdh;
67 static off_t dumplo, fileofs;
68
69 /* Handle buffered writes. */
70 static char buffer[DEV_BSIZE];
71 static size_t fragsz;
72
73 /* 20 phys_avail entry pairs correspond to 10 md_pa's */
74 static struct md_pa dump_map[10];
75
76 static void
77 md_pa_init(void)
78 {
79 int n, idx;
80
81 bzero(dump_map, sizeof(dump_map));
82 for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) {
83 idx = n * 2;
84 if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
85 break;
86 dump_map[n].md_start = dump_avail[idx];
87 dump_map[n].md_size = dump_avail[idx + 1] - dump_avail[idx];
88 }
89 }
90
91 static struct md_pa *
92 md_pa_first(void)
93 {
94
95 return (&dump_map[0]);
96 }
97
98 static struct md_pa *
99 md_pa_next(struct md_pa *mdp)
100 {
101
102 mdp++;
103 if (mdp->md_size == 0)
104 mdp = NULL;
105 return (mdp);
106 }
107
108 static int
109 buf_write(struct dumperinfo *di, char *ptr, size_t sz)
110 {
111 size_t len;
112 int error;
113
114 while (sz) {
115 len = DEV_BSIZE - fragsz;
116 if (len > sz)
117 len = sz;
118 bcopy(ptr, buffer + fragsz, len);
119 fragsz += len;
120 ptr += len;
121 sz -= len;
122 if (fragsz == DEV_BSIZE) {
123 error = dump_write(di, buffer, 0, dumplo,
124 DEV_BSIZE);
125 if (error)
126 return error;
127 dumplo += DEV_BSIZE;
128 fragsz = 0;
129 }
130 }
131
132 return (0);
133 }
134
135 static int
136 buf_flush(struct dumperinfo *di)
137 {
138 int error;
139
140 if (fragsz == 0)
141 return (0);
142
143 error = dump_write(di, buffer, 0, dumplo, DEV_BSIZE);
144 dumplo += DEV_BSIZE;
145 fragsz = 0;
146 return (error);
147 }
148
149 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8)
150
151 static int
152 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg)
153 {
154 struct dumperinfo *di = (struct dumperinfo*)arg;
155 vm_paddr_t a, pa;
156 void *va;
157 uint64_t pgs;
158 size_t counter, sz, chunk;
159 int i, c, error, twiddle;
160 u_int maxdumppgs;
161
162 error = 0; /* catch case in which chunk size is 0 */
163 counter = 0; /* Update twiddle every 16MB */
164 twiddle = 0;
165 va = 0;
166 pgs = mdp->md_size / PAGE_SIZE;
167 pa = mdp->md_start;
168 maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
169 if (maxdumppgs == 0) /* seatbelt */
170 maxdumppgs = 1;
171
172 printf(" chunk %d: %ldMB (%ld pages)", seqnr, PG2MB(pgs), pgs);
173
174 while (pgs) {
175 chunk = pgs;
176 if (chunk > maxdumppgs)
177 chunk = maxdumppgs;
178 sz = chunk << PAGE_SHIFT;
179 counter += sz;
180 if (counter >> 24) {
181 printf(" %ld", PG2MB(pgs));
182 counter &= (1<<24) - 1;
183 }
184 for (i = 0; i < chunk; i++) {
185 a = pa + i * PAGE_SIZE;
186 va = pmap_kenter_temporary(trunc_page(a), i);
187 }
188 error = dump_write(di, va, 0, dumplo, sz);
189 if (error)
190 break;
191 dumplo += sz;
192 pgs -= chunk;
193 pa += sz;
194
195 /* Check for user abort. */
196 c = cncheckc();
197 if (c == 0x03)
198 return (ECANCELED);
199 if (c != -1)
200 printf(" (CTRL-C to abort) ");
201 }
202 printf(" ... %s\n", (error) ? "fail" : "ok");
203 return (error);
204 }
205
206 static int
207 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg)
208 {
209 struct dumperinfo *di = (struct dumperinfo*)arg;
210 Elf_Phdr phdr;
211 uint64_t size;
212 int error;
213
214 size = mdp->md_size;
215 bzero(&phdr, sizeof(phdr));
216 phdr.p_type = PT_LOAD;
217 phdr.p_flags = PF_R; /* XXX */
218 phdr.p_offset = fileofs;
219 phdr.p_vaddr = mdp->md_start;
220 phdr.p_paddr = mdp->md_start;
221 phdr.p_filesz = size;
222 phdr.p_memsz = size;
223 phdr.p_align = PAGE_SIZE;
224
225 error = buf_write(di, (char*)&phdr, sizeof(phdr));
226 fileofs += phdr.p_filesz;
227 return (error);
228 }
229
230 static int
231 cb_size(struct md_pa *mdp, int seqnr, void *arg)
232 {
233 uint64_t *sz = (uint64_t*)arg;
234
235 *sz += (uint64_t)mdp->md_size;
236 return (0);
237 }
238
239 static int
240 foreach_chunk(callback_t cb, void *arg)
241 {
242 struct md_pa *mdp;
243 int error, seqnr;
244
245 seqnr = 0;
246 mdp = md_pa_first();
247 while (mdp != NULL) {
248 error = (*cb)(mdp, seqnr++, arg);
249 if (error)
250 return (-error);
251 mdp = md_pa_next(mdp);
252 }
253 return (seqnr);
254 }
255
256 void
257 dumpsys(struct dumperinfo *di)
258 {
259 Elf_Ehdr ehdr;
260 uint64_t dumpsize;
261 off_t hdrgap;
262 size_t hdrsz;
263 int error;
264
265 if (do_minidump) {
266 minidumpsys(di);
267 return;
268 }
269 bzero(&ehdr, sizeof(ehdr));
270 ehdr.e_ident[EI_MAG0] = ELFMAG0;
271 ehdr.e_ident[EI_MAG1] = ELFMAG1;
272 ehdr.e_ident[EI_MAG2] = ELFMAG2;
273 ehdr.e_ident[EI_MAG3] = ELFMAG3;
274 ehdr.e_ident[EI_CLASS] = ELF_CLASS;
275 #if BYTE_ORDER == LITTLE_ENDIAN
276 ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
277 #else
278 ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
279 #endif
280 ehdr.e_ident[EI_VERSION] = EV_CURRENT;
281 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */
282 ehdr.e_type = ET_CORE;
283 ehdr.e_machine = EM_X86_64;
284 ehdr.e_phoff = sizeof(ehdr);
285 ehdr.e_flags = 0;
286 ehdr.e_ehsize = sizeof(ehdr);
287 ehdr.e_phentsize = sizeof(Elf_Phdr);
288 ehdr.e_shentsize = sizeof(Elf_Shdr);
289
290 md_pa_init();
291
292 /* Calculate dump size. */
293 dumpsize = 0L;
294 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize);
295 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
296 fileofs = MD_ALIGN(hdrsz);
297 dumpsize += fileofs;
298 hdrgap = fileofs - DEV_ALIGN(hdrsz);
299
300 /* Determine dump offset on device. */
301 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
302 error = ENOSPC;
303 goto fail;
304 }
305 dumplo = di->mediaoffset + di->mediasize - dumpsize;
306 dumplo -= sizeof(kdh) * 2;
307
308 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION, dumpsize, di->blocksize);
309
310 printf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20,
311 ehdr.e_phnum);
312
313 /* Dump leader */
314 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
315 if (error)
316 goto fail;
317 dumplo += sizeof(kdh);
318
319 /* Dump ELF header */
320 error = buf_write(di, (char*)&ehdr, sizeof(ehdr));
321 if (error)
322 goto fail;
323
324 /* Dump program headers */
325 error = foreach_chunk(cb_dumphdr, di);
326 if (error < 0)
327 goto fail;
328 buf_flush(di);
329
330 /*
331 * All headers are written using blocked I/O, so we know the
332 * current offset is (still) block aligned. Skip the alignement
333 * in the file to have the segment contents aligned at page
334 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
335 * care and may very well be unaligned within the dump device.
336 */
337 dumplo += hdrgap;
338
339 /* Dump memory chunks (updates dumplo) */
340 error = foreach_chunk(cb_dumpdata, di);
341 if (error < 0)
342 goto fail;
343
344 /* Dump trailer */
345 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
346 if (error)
347 goto fail;
348
349 /* Signal completion, signoff and exit stage left. */
350 dump_write(di, NULL, 0, 0, 0);
351 printf("\nDump complete\n");
352 return;
353
354 fail:
355 if (error < 0)
356 error = -error;
357
358 if (error == ECANCELED)
359 printf("\nDump aborted\n");
360 else if (error == ENOSPC)
361 printf("\nDump failed. Partition too small.\n");
362 else
363 printf("\n** DUMP FAILED (ERROR %d) **\n", error);
364 }
365 Cache object: a2964972640f11b0ed96153cb2e1f617
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