xref: /freebsd/sys/kern/kern_dump.c (revision 15c433351f54e7cd5bec8d36c8e89e6a7fa55b26)
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)	(((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
59 #define	DEV_ALIGN(x)	(((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
60 
61 off_t dumplo;
62 
63 /* Handle buffered writes. */
64 static char buffer[DEV_BSIZE];
65 static size_t fragsz;
66 
67 struct dump_pa dump_map[DUMPSYS_MD_PA_NPAIRS];
68 
69 #if !defined(__powerpc__) && !defined(__sparc__)
70 void
71 dumpsys_gen_pa_init(void)
72 {
73 	int n, idx;
74 
75 	bzero(dump_map, sizeof(dump_map));
76 	for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) {
77 		idx = n * 2;
78 		if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
79 			break;
80 		dump_map[n].pa_start = dump_avail[idx];
81 		dump_map[n].pa_size = dump_avail[idx + 1] - dump_avail[idx];
82 	}
83 }
84 #endif
85 
86 struct dump_pa *
87 dumpsys_gen_pa_next(struct dump_pa *mdp)
88 {
89 
90 	if (mdp == NULL)
91 		return (&dump_map[0]);
92 
93 	mdp++;
94 	if (mdp->pa_size == 0)
95 		mdp = NULL;
96 	return (mdp);
97 }
98 
99 void
100 dumpsys_gen_wbinv_all(void)
101 {
102 
103 }
104 
105 void
106 dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused, size_t chunk __unused,
107     void *va __unused)
108 {
109 
110 }
111 
112 #if !defined(__sparc__)
113 int
114 dumpsys_gen_write_aux_headers(struct dumperinfo *di)
115 {
116 
117 	return (0);
118 }
119 #endif
120 
121 int
122 dumpsys_buf_write(struct dumperinfo *di, char *ptr, size_t sz)
123 {
124 	size_t len;
125 	int error;
126 
127 	while (sz) {
128 		len = DEV_BSIZE - fragsz;
129 		if (len > sz)
130 			len = sz;
131 		bcopy(ptr, buffer + fragsz, len);
132 		fragsz += len;
133 		ptr += len;
134 		sz -= len;
135 		if (fragsz == DEV_BSIZE) {
136 			error = dump_write(di, buffer, 0, dumplo,
137 			    DEV_BSIZE);
138 			if (error)
139 				return (error);
140 			dumplo += DEV_BSIZE;
141 			fragsz = 0;
142 		}
143 	}
144 	return (0);
145 }
146 
147 int
148 dumpsys_buf_flush(struct dumperinfo *di)
149 {
150 	int error;
151 
152 	if (fragsz == 0)
153 		return (0);
154 
155 	error = dump_write(di, buffer, 0, dumplo, DEV_BSIZE);
156 	dumplo += DEV_BSIZE;
157 	fragsz = 0;
158 	return (error);
159 }
160 
161 CTASSERT(PAGE_SHIFT < 20);
162 #define PG2MB(pgs) ((pgs + (1 << (20 - PAGE_SHIFT)) - 1) >> (20 - PAGE_SHIFT))
163 
164 int
165 dumpsys_cb_dumpdata(struct dump_pa *mdp, int seqnr, void *arg)
166 {
167 	struct dumperinfo *di = (struct dumperinfo*)arg;
168 	vm_paddr_t pa;
169 	void *va;
170 	uint64_t pgs;
171 	size_t counter, sz, chunk;
172 	int c, error;
173 	u_int maxdumppgs;
174 
175 	error = 0;	/* catch case in which chunk size is 0 */
176 	counter = 0;	/* Update twiddle every 16MB */
177 	va = 0;
178 	pgs = mdp->pa_size / PAGE_SIZE;
179 	pa = mdp->pa_start;
180 	maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
181 	if (maxdumppgs == 0)	/* seatbelt */
182 		maxdumppgs = 1;
183 
184 	printf("  chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
185 	    (uintmax_t)pgs);
186 
187 	dumpsys_wbinv_all();
188 	while (pgs) {
189 		chunk = pgs;
190 		if (chunk > maxdumppgs)
191 			chunk = maxdumppgs;
192 		sz = chunk << PAGE_SHIFT;
193 		counter += sz;
194 		if (counter >> 24) {
195 			printf(" %ju", (uintmax_t)PG2MB(pgs));
196 			counter &= (1 << 24) - 1;
197 		}
198 
199 		dumpsys_map_chunk(pa, chunk, &va);
200 #ifdef SW_WATCHDOG
201 		wdog_kern_pat(WD_LASTVAL);
202 #endif
203 
204 		error = dump_write(di, va, 0, dumplo, sz);
205 		dumpsys_unmap_chunk(pa, chunk, va);
206 		if (error)
207 			break;
208 		dumplo += sz;
209 		pgs -= chunk;
210 		pa += sz;
211 
212 		/* Check for user abort. */
213 		c = cncheckc();
214 		if (c == 0x03)
215 			return (ECANCELED);
216 		if (c != -1)
217 			printf(" (CTRL-C to abort) ");
218 	}
219 	printf(" ... %s\n", (error) ? "fail" : "ok");
220 	return (error);
221 }
222 
223 int
224 dumpsys_foreach_chunk(dumpsys_callback_t cb, void *arg)
225 {
226 	struct dump_pa *mdp;
227 	int error, seqnr;
228 
229 	seqnr = 0;
230 	mdp = dumpsys_pa_next(NULL);
231 	while (mdp != NULL) {
232 		error = (*cb)(mdp, seqnr++, arg);
233 		if (error)
234 			return (-error);
235 		mdp = dumpsys_pa_next(mdp);
236 	}
237 	return (seqnr);
238 }
239 
240 #if !defined(__sparc__)
241 static off_t fileofs;
242 
243 static int
244 cb_dumphdr(struct dump_pa *mdp, int seqnr, void *arg)
245 {
246 	struct dumperinfo *di = (struct dumperinfo*)arg;
247 	Elf_Phdr phdr;
248 	uint64_t size;
249 	int error;
250 
251 	size = mdp->pa_size;
252 	bzero(&phdr, sizeof(phdr));
253 	phdr.p_type = PT_LOAD;
254 	phdr.p_flags = PF_R;			/* XXX */
255 	phdr.p_offset = fileofs;
256 #ifdef __powerpc__
257 	phdr.p_vaddr = (do_minidump? mdp->pa_start : ~0L);
258 	phdr.p_paddr = (do_minidump? ~0L : mdp->pa_start);
259 #else
260 	phdr.p_vaddr = mdp->pa_start;
261 	phdr.p_paddr = mdp->pa_start;
262 #endif
263 	phdr.p_filesz = size;
264 	phdr.p_memsz = size;
265 	phdr.p_align = PAGE_SIZE;
266 
267 	error = dumpsys_buf_write(di, (char*)&phdr, sizeof(phdr));
268 	fileofs += phdr.p_filesz;
269 	return (error);
270 }
271 
272 static int
273 cb_size(struct dump_pa *mdp, int seqnr, void *arg)
274 {
275 	uint64_t *sz;
276 
277 	sz = (uint64_t *)arg;
278 	*sz += (uint64_t)mdp->pa_size;
279 	return (0);
280 }
281 
282 int
283 dumpsys_generic(struct dumperinfo *di)
284 {
285 	static struct kerneldumpheader kdh;
286 	Elf_Ehdr ehdr;
287 	uint64_t dumpsize;
288 	off_t hdrgap;
289 	size_t hdrsz;
290 	int error;
291 
292 #ifndef __powerpc__
293 	if (do_minidump)
294 		return (minidumpsys(di));
295 #endif
296 
297 	bzero(&ehdr, sizeof(ehdr));
298 	ehdr.e_ident[EI_MAG0] = ELFMAG0;
299 	ehdr.e_ident[EI_MAG1] = ELFMAG1;
300 	ehdr.e_ident[EI_MAG2] = ELFMAG2;
301 	ehdr.e_ident[EI_MAG3] = ELFMAG3;
302 	ehdr.e_ident[EI_CLASS] = ELF_CLASS;
303 #if BYTE_ORDER == LITTLE_ENDIAN
304 	ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
305 #else
306 	ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
307 #endif
308 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
309 	ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE;	/* XXX big picture? */
310 	ehdr.e_type = ET_CORE;
311 	ehdr.e_machine = EM_VALUE;
312 	ehdr.e_phoff = sizeof(ehdr);
313 	ehdr.e_flags = 0;
314 	ehdr.e_ehsize = sizeof(ehdr);
315 	ehdr.e_phentsize = sizeof(Elf_Phdr);
316 	ehdr.e_shentsize = sizeof(Elf_Shdr);
317 
318 	dumpsys_pa_init();
319 
320 	/* Calculate dump size. */
321 	dumpsize = 0L;
322 	ehdr.e_phnum = dumpsys_foreach_chunk(cb_size, &dumpsize) +
323 	    DUMPSYS_NUM_AUX_HDRS;
324 	hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
325 	fileofs = MD_ALIGN(hdrsz);
326 	dumpsize += fileofs;
327 	hdrgap = fileofs - DEV_ALIGN(hdrsz);
328 
329 	/* Determine dump offset on device. */
330 	if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
331 		error = ENOSPC;
332 		goto fail;
333 	}
334 	dumplo = di->mediaoffset + di->mediasize - dumpsize;
335 	dumplo -= sizeof(kdh) * 2;
336 
337 	mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_ARCH_VERSION, dumpsize,
338 	    di->blocksize);
339 
340 	printf("Dumping %ju MB (%d chunks)\n", (uintmax_t)dumpsize >> 20,
341 	    ehdr.e_phnum - DUMPSYS_NUM_AUX_HDRS);
342 
343 	/* Dump leader */
344 	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
345 	if (error)
346 		goto fail;
347 	dumplo += sizeof(kdh);
348 
349 	/* Dump ELF header */
350 	error = dumpsys_buf_write(di, (char*)&ehdr, sizeof(ehdr));
351 	if (error)
352 		goto fail;
353 
354 	/* Dump program headers */
355 	error = dumpsys_foreach_chunk(cb_dumphdr, di);
356 	if (error < 0)
357 		goto fail;
358 	error = dumpsys_write_aux_headers(di);
359 	if (error < 0)
360 		goto fail;
361 	dumpsys_buf_flush(di);
362 
363 	/*
364 	 * All headers are written using blocked I/O, so we know the
365 	 * current offset is (still) block aligned. Skip the alignement
366 	 * in the file to have the segment contents aligned at page
367 	 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
368 	 * care and may very well be unaligned within the dump device.
369 	 */
370 	dumplo += hdrgap;
371 
372 	/* Dump memory chunks (updates dumplo) */
373 	error = dumpsys_foreach_chunk(dumpsys_cb_dumpdata, di);
374 	if (error < 0)
375 		goto fail;
376 
377 	/* Dump trailer */
378 	error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
379 	if (error)
380 		goto fail;
381 
382 	/* Signal completion, signoff and exit stage left. */
383 	dump_write(di, NULL, 0, 0, 0);
384 	printf("\nDump complete\n");
385 	return (0);
386 
387  fail:
388 	if (error < 0)
389 		error = -error;
390 
391 	if (error == ECANCELED)
392 		printf("\nDump aborted\n");
393 	else if (error == ENOSPC)
394 		printf("\nDump failed. Partition too small.\n");
395 	else
396 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
397 	return (error);
398 }
399 #endif
400