xref: /freebsd/sys/kern/kern_dump.c (revision 41059135ce931c0f1014a999ffabc6bc470ce856)
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("$FreeBSD$");
29 
30 #include "opt_watchdog.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/conf.h>
35 #include <sys/cons.h>
36 #include <sys/kernel.h>
37 #include <sys/proc.h>
38 #include <sys/kerneldump.h>
39 #ifdef SW_WATCHDOG
40 #include <sys/watchdog.h>
41 #endif
42 #include <vm/vm.h>
43 #include <vm/vm_param.h>
44 #include <vm/pmap.h>
45 #include <machine/dump.h>
46 #include <machine/elf.h>
47 #include <machine/md_var.h>
48 #include <machine/pcb.h>
49 
50 CTASSERT(sizeof(struct kerneldumpheader) == 512);
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)	roundup2((off_t)(x), PAGE_SIZE)
59 
60 off_t dumplo;
61 
62 /* Handle buffered writes. */
63 static size_t fragsz;
64 
65 struct dump_pa dump_map[DUMPSYS_MD_PA_NPAIRS];
66 
67 #if !defined(__powerpc__) && !defined(__sparc__)
68 void
69 dumpsys_gen_pa_init(void)
70 {
71 	int n, idx;
72 
73 	bzero(dump_map, sizeof(dump_map));
74 	for (n = 0; n < nitems(dump_map); n++) {
75 		idx = n * 2;
76 		if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
77 			break;
78 		dump_map[n].pa_start = dump_avail[idx];
79 		dump_map[n].pa_size = dump_avail[idx + 1] - dump_avail[idx];
80 	}
81 }
82 #endif
83 
84 struct dump_pa *
85 dumpsys_gen_pa_next(struct dump_pa *mdp)
86 {
87 
88 	if (mdp == NULL)
89 		return (&dump_map[0]);
90 
91 	mdp++;
92 	if (mdp->pa_size == 0)
93 		mdp = NULL;
94 	return (mdp);
95 }
96 
97 void
98 dumpsys_gen_wbinv_all(void)
99 {
100 
101 }
102 
103 void
104 dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused, size_t chunk __unused,
105     void *va __unused)
106 {
107 
108 }
109 
110 #if !defined(__sparc__)
111 int
112 dumpsys_gen_write_aux_headers(struct dumperinfo *di)
113 {
114 
115 	return (0);
116 }
117 #endif
118 
119 int
120 dumpsys_buf_seek(struct dumperinfo *di, size_t sz)
121 {
122 	static uint8_t buf[DEV_BSIZE];
123 	size_t nbytes;
124 	int error;
125 
126 	bzero(buf, sizeof(buf));
127 
128 	while (sz > 0) {
129 		nbytes = MIN(sz, sizeof(buf));
130 
131 		error = dump_write(di, buf, 0, dumplo, nbytes);
132 		if (error)
133 			return (error);
134 		dumplo += nbytes;
135 
136 		sz -= nbytes;
137 	}
138 
139 	return (0);
140 }
141 
142 int
143 dumpsys_buf_write(struct dumperinfo *di, char *ptr, size_t sz)
144 {
145 	size_t len;
146 	int error;
147 
148 	while (sz) {
149 		len = di->blocksize - fragsz;
150 		if (len > sz)
151 			len = sz;
152 		memcpy((char *)di->blockbuf + fragsz, ptr, len);
153 		fragsz += len;
154 		ptr += len;
155 		sz -= len;
156 		if (fragsz == di->blocksize) {
157 			error = dump_write(di, di->blockbuf, 0, dumplo,
158 			    di->blocksize);
159 			if (error)
160 				return (error);
161 			dumplo += di->blocksize;
162 			fragsz = 0;
163 		}
164 	}
165 	return (0);
166 }
167 
168 int
169 dumpsys_buf_flush(struct dumperinfo *di)
170 {
171 	int error;
172 
173 	if (fragsz == 0)
174 		return (0);
175 
176 	error = dump_write(di, di->blockbuf, 0, dumplo, di->blocksize);
177 	dumplo += di->blocksize;
178 	fragsz = 0;
179 	return (error);
180 }
181 
182 CTASSERT(PAGE_SHIFT < 20);
183 #define PG2MB(pgs) ((pgs + (1 << (20 - PAGE_SHIFT)) - 1) >> (20 - PAGE_SHIFT))
184 
185 int
186 dumpsys_cb_dumpdata(struct dump_pa *mdp, int seqnr, void *arg)
187 {
188 	struct dumperinfo *di = (struct dumperinfo*)arg;
189 	vm_paddr_t pa;
190 	void *va;
191 	uint64_t pgs;
192 	size_t counter, sz, chunk;
193 	int c, error;
194 	u_int maxdumppgs;
195 
196 	error = 0;	/* catch case in which chunk size is 0 */
197 	counter = 0;	/* Update twiddle every 16MB */
198 	va = NULL;
199 	pgs = mdp->pa_size / PAGE_SIZE;
200 	pa = mdp->pa_start;
201 	maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
202 	if (maxdumppgs == 0)	/* seatbelt */
203 		maxdumppgs = 1;
204 
205 	printf("  chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
206 	    (uintmax_t)pgs);
207 
208 	dumpsys_wbinv_all();
209 	while (pgs) {
210 		chunk = pgs;
211 		if (chunk > maxdumppgs)
212 			chunk = maxdumppgs;
213 		sz = chunk << PAGE_SHIFT;
214 		counter += sz;
215 		if (counter >> 24) {
216 			printf(" %ju", (uintmax_t)PG2MB(pgs));
217 			counter &= (1 << 24) - 1;
218 		}
219 
220 		dumpsys_map_chunk(pa, chunk, &va);
221 #ifdef SW_WATCHDOG
222 		wdog_kern_pat(WD_LASTVAL);
223 #endif
224 
225 		error = dump_write(di, va, 0, dumplo, sz);
226 		dumpsys_unmap_chunk(pa, chunk, va);
227 		if (error)
228 			break;
229 		dumplo += sz;
230 		pgs -= chunk;
231 		pa += sz;
232 
233 		/* Check for user abort. */
234 		c = cncheckc();
235 		if (c == 0x03)
236 			return (ECANCELED);
237 		if (c != -1)
238 			printf(" (CTRL-C to abort) ");
239 	}
240 	printf(" ... %s\n", (error) ? "fail" : "ok");
241 	return (error);
242 }
243 
244 int
245 dumpsys_foreach_chunk(dumpsys_callback_t cb, void *arg)
246 {
247 	struct dump_pa *mdp;
248 	int error, seqnr;
249 
250 	seqnr = 0;
251 	mdp = dumpsys_pa_next(NULL);
252 	while (mdp != NULL) {
253 		error = (*cb)(mdp, seqnr++, arg);
254 		if (error)
255 			return (-error);
256 		mdp = dumpsys_pa_next(mdp);
257 	}
258 	return (seqnr);
259 }
260 
261 #if !defined(__sparc__)
262 static off_t fileofs;
263 
264 static int
265 cb_dumphdr(struct dump_pa *mdp, int seqnr, void *arg)
266 {
267 	struct dumperinfo *di = (struct dumperinfo*)arg;
268 	Elf_Phdr phdr;
269 	uint64_t size;
270 	int error;
271 
272 	size = mdp->pa_size;
273 	bzero(&phdr, sizeof(phdr));
274 	phdr.p_type = PT_LOAD;
275 	phdr.p_flags = PF_R;			/* XXX */
276 	phdr.p_offset = fileofs;
277 #ifdef __powerpc__
278 	phdr.p_vaddr = (do_minidump? mdp->pa_start : ~0L);
279 	phdr.p_paddr = (do_minidump? ~0L : mdp->pa_start);
280 #else
281 	phdr.p_vaddr = mdp->pa_start;
282 	phdr.p_paddr = mdp->pa_start;
283 #endif
284 	phdr.p_filesz = size;
285 	phdr.p_memsz = size;
286 	phdr.p_align = PAGE_SIZE;
287 
288 	error = dumpsys_buf_write(di, (char*)&phdr, sizeof(phdr));
289 	fileofs += phdr.p_filesz;
290 	return (error);
291 }
292 
293 static int
294 cb_size(struct dump_pa *mdp, int seqnr, void *arg)
295 {
296 	uint64_t *sz;
297 
298 	sz = (uint64_t *)arg;
299 	*sz += (uint64_t)mdp->pa_size;
300 	return (0);
301 }
302 
303 int
304 dumpsys_generic(struct dumperinfo *di)
305 {
306 	static struct kerneldumpheader kdh;
307 	Elf_Ehdr ehdr;
308 	uint64_t dumpsize;
309 	off_t hdrgap;
310 	size_t hdrsz;
311 	int error;
312 
313 #ifndef __powerpc__
314 	if (do_minidump)
315 		return (minidumpsys(di));
316 #endif
317 
318 	bzero(&ehdr, sizeof(ehdr));
319 	ehdr.e_ident[EI_MAG0] = ELFMAG0;
320 	ehdr.e_ident[EI_MAG1] = ELFMAG1;
321 	ehdr.e_ident[EI_MAG2] = ELFMAG2;
322 	ehdr.e_ident[EI_MAG3] = ELFMAG3;
323 	ehdr.e_ident[EI_CLASS] = ELF_CLASS;
324 #if BYTE_ORDER == LITTLE_ENDIAN
325 	ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
326 #else
327 	ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
328 #endif
329 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
330 	ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE;	/* XXX big picture? */
331 	ehdr.e_type = ET_CORE;
332 	ehdr.e_machine = EM_VALUE;
333 	ehdr.e_phoff = sizeof(ehdr);
334 	ehdr.e_flags = 0;
335 	ehdr.e_ehsize = sizeof(ehdr);
336 	ehdr.e_phentsize = sizeof(Elf_Phdr);
337 	ehdr.e_shentsize = sizeof(Elf_Shdr);
338 
339 	dumpsys_pa_init();
340 
341 	/* Calculate dump size. */
342 	dumpsize = 0L;
343 	ehdr.e_phnum = dumpsys_foreach_chunk(cb_size, &dumpsize) +
344 	    DUMPSYS_NUM_AUX_HDRS;
345 	hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
346 	fileofs = MD_ALIGN(hdrsz);
347 	dumpsize += fileofs;
348 	hdrgap = fileofs - roundup2((off_t)hdrsz, di->blocksize);
349 
350 	/* Determine dump offset on device. */
351 	if (di->mediasize < SIZEOF_METADATA + dumpsize + di->blocksize * 2 +
352 	    kerneldumpcrypto_dumpkeysize(di->kdc)) {
353 		error = ENOSPC;
354 		goto fail;
355 	}
356 	dumplo = di->mediaoffset + di->mediasize - dumpsize;
357 	dumplo -= di->blocksize * 2;
358 	dumplo -= kerneldumpcrypto_dumpkeysize(di->kdc);
359 
360 	/* Initialize kernel dump crypto. */
361 	error = kerneldumpcrypto_init(di->kdc);
362 	if (error)
363 		goto fail;
364 
365 	mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_ARCH_VERSION, dumpsize,
366 	    kerneldumpcrypto_dumpkeysize(di->kdc), di->blocksize);
367 
368 	printf("Dumping %ju MB (%d chunks)\n", (uintmax_t)dumpsize >> 20,
369 	    ehdr.e_phnum - DUMPSYS_NUM_AUX_HDRS);
370 
371 	/* Dump leader */
372 	error = dump_write_header(di, &kdh, 0, dumplo);
373 	if (error)
374 		goto fail;
375 	dumplo += di->blocksize;
376 
377 	/* Dump key */
378 	error = dump_write_key(di, 0, dumplo);
379 	if (error)
380 		goto fail;
381 	dumplo += kerneldumpcrypto_dumpkeysize(di->kdc);
382 
383 	/* Dump ELF header */
384 	error = dumpsys_buf_write(di, (char*)&ehdr, sizeof(ehdr));
385 	if (error)
386 		goto fail;
387 
388 	/* Dump program headers */
389 	error = dumpsys_foreach_chunk(cb_dumphdr, di);
390 	if (error < 0)
391 		goto fail;
392 	error = dumpsys_write_aux_headers(di);
393 	if (error < 0)
394 		goto fail;
395 	dumpsys_buf_flush(di);
396 
397 	/*
398 	 * All headers are written using blocked I/O, so we know the
399 	 * current offset is (still) block aligned. Skip the alignement
400 	 * in the file to have the segment contents aligned at page
401 	 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
402 	 * care and may very well be unaligned within the dump device.
403 	 */
404 	error = dumpsys_buf_seek(di, (size_t)hdrgap);
405 	if (error)
406 		goto fail;
407 
408 	/* Dump memory chunks (updates dumplo) */
409 	error = dumpsys_foreach_chunk(dumpsys_cb_dumpdata, di);
410 	if (error < 0)
411 		goto fail;
412 
413 	/* Dump trailer */
414 	error = dump_write_header(di, &kdh, 0, dumplo);
415 	if (error)
416 		goto fail;
417 	dumplo += di->blocksize;
418 
419 	/* Signal completion, signoff and exit stage left. */
420 	dump_write(di, NULL, 0, 0, 0);
421 	printf("\nDump complete\n");
422 	return (0);
423 
424  fail:
425 	if (error < 0)
426 		error = -error;
427 
428 	if (error == ECANCELED)
429 		printf("\nDump aborted\n");
430 	else if (error == ENOSPC)
431 		printf("\nDump failed. Partition too small.\n");
432 	else
433 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
434 	return (error);
435 }
436 #endif
437