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 * $FreeBSD: src/sys/amd64/amd64/dump_machdep.c,v 1.18 2009/05/29 21:27:12 jamie Exp $
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/conf.h>
32 #include <sys/cons.h>
33 #include <sys/sysctl.h>
34 #include <sys/device.h>
35 #include <sys/kernel.h>
36 #include <sys/kerneldump.h>
37 #include <sys/kbio.h>
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 #include <machine/elf.h>
41 #include <machine/md_var.h>
42 #include <machine/thread.h>
43 #include <machine/vmparam.h>
44
45 CTASSERT(sizeof(struct kerneldumpheader) == 512);
46
47 static int do_minidump = 1;
48 TUNABLE_INT("debug.minidump", &do_minidump);
49 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0,
50 "Enable mini crash dumps");
51
52 /*
53 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
54 * is to protect us from metadata and to protect metadata from us.
55 */
56 #define SIZEOF_METADATA (64*1024)
57
58 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
59 #define DEV_ALIGN(x) roundup2((off_t)(x), DEV_BSIZE)
60
61 struct md_pa {
62 vm_paddr_t md_start;
63 vm_paddr_t md_size;
64 };
65
66 typedef int callback_t(struct md_pa *, int, void *);
67
68 static struct kerneldumpheader kdh;
69 static off_t dumplo, fileofs;
70
71 /* Handle buffered writes. */
72 static char buffer[DEV_BSIZE];
73 static size_t fragsz;
74
75 static struct md_pa dump_map[VM_PHYSSEG_MAX+1];
76
77 static void
md_pa_init(void)78 md_pa_init(void)
79 {
80 int n;
81
82 bzero(dump_map, sizeof(dump_map));
83 for (n = 0; n < NELEM(dump_map); n++) {
84 if (dump_avail[n].phys_beg == 0 && dump_avail[n].phys_end == 0)
85 break;
86 dump_map[n].md_start = dump_avail[n].phys_beg;
87 dump_map[n].md_size = dump_avail[n].phys_end -
88 dump_avail[n].phys_beg;
89 }
90 }
91
92 static struct md_pa *
md_pa_first(void)93 md_pa_first(void)
94 {
95
96 return (&dump_map[0]);
97 }
98
99 static struct md_pa *
md_pa_next(struct md_pa * mdp)100 md_pa_next(struct md_pa *mdp)
101 {
102
103 mdp++;
104 if (mdp->md_size == 0)
105 mdp = NULL;
106 return (mdp);
107 }
108
109 static int
buf_write(struct dumperinfo * di,char * ptr,size_t sz)110 buf_write(struct dumperinfo *di, char *ptr, size_t sz)
111 {
112 size_t len;
113 int error;
114
115 while (sz) {
116 len = DEV_BSIZE - fragsz;
117 if (len > sz)
118 len = sz;
119 bcopy(ptr, buffer + fragsz, len);
120 fragsz += len;
121 ptr += len;
122 sz -= len;
123 if (fragsz == DEV_BSIZE) {
124 error = dev_ddump(di->priv, buffer, 0, dumplo,
125 DEV_BSIZE);
126 if (error)
127 return error;
128 dumplo += DEV_BSIZE;
129 fragsz = 0;
130 }
131 }
132
133 return (0);
134 }
135
136 static int
buf_flush(struct dumperinfo * di)137 buf_flush(struct dumperinfo *di)
138 {
139 int error;
140
141 if (fragsz == 0)
142 return (0);
143
144 error = dev_ddump(di->priv, buffer, 0, dumplo, DEV_BSIZE);
145 dumplo += DEV_BSIZE;
146 fragsz = 0;
147 return (error);
148 }
149
150 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8)
151
152 static int
cb_dumpdata(struct md_pa * mdp,int seqnr,void * arg)153 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg)
154 {
155 struct dumperinfo *di = (struct dumperinfo*)arg;
156 vm_paddr_t a, pa;
157 void *va;
158 uint64_t pgs;
159 size_t counter, sz, chunk;
160 int i, c, error;
161 int max_iosize;
162
163 error = 0; /* catch case in which chunk size is 0 */
164 counter = 0; /* Update twiddle every 16MB */
165 va = NULL;
166 pgs = mdp->md_size / PAGE_SIZE;
167 pa = mdp->md_start;
168 max_iosize = min(MAXPHYS, di->maxiosize);
169
170 kprintf(" chunk %d: %ldMB (%ld pages)", seqnr, PG2MB(pgs), pgs);
171
172 cnpoll(TRUE);
173 while (pgs) {
174 chunk = pgs;
175 if (chunk > (max_iosize/PAGE_SIZE))
176 chunk = max_iosize/PAGE_SIZE;
177 sz = chunk << PAGE_SHIFT;
178 counter += sz;
179 if (counter >> 24) {
180 kprintf(" %ld", PG2MB(pgs));
181 counter &= (1<<24) - 1;
182 }
183 for (i = 0; i < chunk; i++) {
184 a = pa + i * PAGE_SIZE;
185 va = pmap_kenter_temporary(trunc_page(a), i);
186 }
187 smp_invltlb();
188 error = dev_ddump(di->priv, 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 error = ECANCELED;
199 goto done;
200 }
201 if (c != -1 && c != NOKEY)
202 kprintf(" (CTRL-C to abort) ");
203 }
204 kprintf(" ... %s\n", (error) ? "fail" : "ok");
205 done:
206 cnpoll(FALSE);
207 return (error);
208 }
209
210 static int
cb_dumphdr(struct md_pa * mdp,int seqnr,void * arg)211 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg)
212 {
213 struct dumperinfo *di = (struct dumperinfo*)arg;
214 Elf_Phdr phdr;
215 uint64_t size;
216 int error;
217
218 size = mdp->md_size;
219 bzero(&phdr, sizeof(phdr));
220 phdr.p_type = PT_LOAD;
221 phdr.p_flags = PF_R; /* XXX */
222 phdr.p_offset = fileofs;
223 phdr.p_vaddr = mdp->md_start;
224 phdr.p_paddr = mdp->md_start;
225 phdr.p_filesz = size;
226 phdr.p_memsz = size;
227 phdr.p_align = PAGE_SIZE;
228
229 error = buf_write(di, (char*)&phdr, sizeof(phdr));
230 fileofs += phdr.p_filesz;
231 return (error);
232 }
233
234 static int
cb_size(struct md_pa * mdp,int seqnr,void * arg)235 cb_size(struct md_pa *mdp, int seqnr, void *arg)
236 {
237 uint64_t *sz = (uint64_t*)arg;
238
239 *sz += (uint64_t)mdp->md_size;
240 return (0);
241 }
242
243 static int
foreach_chunk(callback_t cb,void * arg)244 foreach_chunk(callback_t cb, void *arg)
245 {
246 struct md_pa *mdp;
247 int error, seqnr;
248
249 seqnr = 0;
250 mdp = md_pa_first();
251 while (mdp != NULL) {
252 error = (*cb)(mdp, seqnr++, arg);
253 if (error)
254 return (-error);
255 mdp = md_pa_next(mdp);
256 }
257 return (seqnr);
258 }
259
260 void
md_dumpsys(struct dumperinfo * di)261 md_dumpsys(struct dumperinfo *di)
262 {
263 Elf_Ehdr ehdr;
264 uint64_t dumpsize;
265 off_t hdrgap;
266 size_t hdrsz;
267 int error;
268
269 /*
270 * Save context if dump called without panic.
271 */
272 if (dumpthread == NULL) {
273 savectx(&dumppcb);
274 dumpthread = curthread;
275 }
276
277 if (do_minidump) {
278 minidumpsys(di);
279 return;
280 }
281 bzero(&ehdr, sizeof(ehdr));
282 ehdr.e_ident[EI_MAG0] = ELFMAG0;
283 ehdr.e_ident[EI_MAG1] = ELFMAG1;
284 ehdr.e_ident[EI_MAG2] = ELFMAG2;
285 ehdr.e_ident[EI_MAG3] = ELFMAG3;
286 ehdr.e_ident[EI_CLASS] = ELF_CLASS;
287 #if BYTE_ORDER == LITTLE_ENDIAN
288 ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
289 #else
290 ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
291 #endif
292 ehdr.e_ident[EI_VERSION] = EV_CURRENT;
293 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */
294 ehdr.e_type = ET_CORE;
295 ehdr.e_machine = EM_X86_64;
296 ehdr.e_phoff = sizeof(ehdr);
297 ehdr.e_flags = 0;
298 ehdr.e_ehsize = sizeof(ehdr);
299 ehdr.e_phentsize = sizeof(Elf_Phdr);
300 ehdr.e_shentsize = sizeof(Elf_Shdr);
301
302 md_pa_init();
303
304 /* Calculate dump size. */
305 dumpsize = 0L;
306 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize);
307 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
308 fileofs = MD_ALIGN(hdrsz);
309 dumpsize += fileofs;
310 hdrgap = fileofs - DEV_ALIGN(hdrsz);
311
312 /* Determine dump offset on device. */
313 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
314 error = ENOSPC;
315 goto fail;
316 }
317 dumplo = di->mediaoffset + di->mediasize - dumpsize;
318 dumplo -= sizeof(kdh) * 2;
319
320 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION,
321 dumpsize, di->blocksize);
322
323 kprintf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20,
324 ehdr.e_phnum);
325
326 /* Dump leader */
327 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh));
328 if (error)
329 goto fail;
330 dumplo += sizeof(kdh);
331
332 /* Dump ELF header */
333 error = buf_write(di, (char*)&ehdr, sizeof(ehdr));
334 if (error)
335 goto fail;
336
337 /* Dump program headers */
338 error = foreach_chunk(cb_dumphdr, di);
339 if (error < 0)
340 goto fail;
341 buf_flush(di);
342
343 /*
344 * All headers are written using blocked I/O, so we know the
345 * current offset is (still) block aligned. Skip the alignement
346 * in the file to have the segment contents aligned at page
347 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
348 * care and may very well be unaligned within the dump device.
349 */
350 dumplo += hdrgap;
351
352 /* Dump memory chunks (updates dumplo) */
353 error = foreach_chunk(cb_dumpdata, di);
354 if (error < 0)
355 goto fail;
356
357 /* Dump trailer */
358 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh));
359 if (error)
360 goto fail;
361
362 /* Signal completion, signoff and exit stage left. */
363 dev_ddump(di->priv, NULL, 0, 0, 0);
364 kprintf("\nDump complete\n");
365 return;
366
367 fail:
368 if (error < 0)
369 error = -error;
370
371 if (error == ECANCELED)
372 kprintf("\nDump aborted\n");
373 else if (error == ENOSPC)
374 kprintf("\nDump failed. Partition too small.\n");
375 else
376 kprintf("\n** DUMP FAILED (ERROR %d) **\n", error);
377 }
378