xref: /freebsd/sys/kern/kern_dump.c (revision d65c432aa693043a241e9061d040c4d2b3e86d96)
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 <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/conf.h>
33 #include <sys/cons.h>
34 #include <sys/kernel.h>
35 #include <sys/proc.h>
36 #include <sys/kerneldump.h>
37 #include <sys/watchdog.h>
38 #include <vm/vm.h>
39 #include <vm/vm_param.h>
40 #include <vm/vm_page.h>
41 #include <vm/vm_phys.h>
42 #include <vm/pmap.h>
43 #include <machine/dump.h>
44 #include <machine/elf.h>
45 #include <machine/md_var.h>
46 #include <machine/pcb.h>
47 
48 CTASSERT(sizeof(struct kerneldumpheader) == 512);
49 
50 #define	MD_ALIGN(x)	roundup2((off_t)(x), PAGE_SIZE)
51 
52 /* Handle buffered writes. */
53 static size_t fragsz;
54 
55 struct dump_pa dump_map[DUMPSYS_MD_PA_NPAIRS];
56 
57 #if !defined(__powerpc__) && !defined(__sparc__)
58 void
59 dumpsys_gen_pa_init(void)
60 {
61 	int n, idx;
62 
63 	bzero(dump_map, sizeof(dump_map));
64 	for (n = 0; n < nitems(dump_map); n++) {
65 		idx = n * 2;
66 		if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
67 			break;
68 		dump_map[n].pa_start = dump_avail[idx];
69 		dump_map[n].pa_size = dump_avail[idx + 1] - dump_avail[idx];
70 	}
71 }
72 #endif
73 
74 struct dump_pa *
75 dumpsys_gen_pa_next(struct dump_pa *mdp)
76 {
77 
78 	if (mdp == NULL)
79 		return (&dump_map[0]);
80 
81 	mdp++;
82 	if (mdp->pa_size == 0)
83 		mdp = NULL;
84 	return (mdp);
85 }
86 
87 void
88 dumpsys_gen_wbinv_all(void)
89 {
90 
91 }
92 
93 void
94 dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused, size_t chunk __unused,
95     void *va __unused)
96 {
97 
98 }
99 
100 #if !defined(__sparc__)
101 int
102 dumpsys_gen_write_aux_headers(struct dumperinfo *di)
103 {
104 
105 	return (0);
106 }
107 #endif
108 
109 int
110 dumpsys_buf_seek(struct dumperinfo *di, size_t sz)
111 {
112 	static uint8_t buf[DEV_BSIZE];
113 	size_t nbytes;
114 	int error;
115 
116 	bzero(buf, sizeof(buf));
117 
118 	while (sz > 0) {
119 		nbytes = MIN(sz, sizeof(buf));
120 
121 		error = dump_append(di, buf, 0, nbytes);
122 		if (error)
123 			return (error);
124 		sz -= nbytes;
125 	}
126 
127 	return (0);
128 }
129 
130 int
131 dumpsys_buf_write(struct dumperinfo *di, char *ptr, size_t sz)
132 {
133 	size_t len;
134 	int error;
135 
136 	while (sz) {
137 		len = di->blocksize - fragsz;
138 		if (len > sz)
139 			len = sz;
140 		memcpy((char *)di->blockbuf + fragsz, ptr, len);
141 		fragsz += len;
142 		ptr += len;
143 		sz -= len;
144 		if (fragsz == di->blocksize) {
145 			error = dump_append(di, di->blockbuf, 0, di->blocksize);
146 			if (error)
147 				return (error);
148 			fragsz = 0;
149 		}
150 	}
151 	return (0);
152 }
153 
154 int
155 dumpsys_buf_flush(struct dumperinfo *di)
156 {
157 	int error;
158 
159 	if (fragsz == 0)
160 		return (0);
161 
162 	error = dump_append(di, di->blockbuf, 0, di->blocksize);
163 	fragsz = 0;
164 	return (error);
165 }
166 
167 CTASSERT(PAGE_SHIFT < 20);
168 #define PG2MB(pgs) ((pgs + (1 << (20 - PAGE_SHIFT)) - 1) >> (20 - PAGE_SHIFT))
169 
170 int
171 dumpsys_cb_dumpdata(struct dump_pa *mdp, int seqnr, void *arg)
172 {
173 	struct dumperinfo *di = (struct dumperinfo*)arg;
174 	vm_paddr_t pa;
175 	void *va;
176 	uint64_t pgs;
177 	size_t counter, sz, chunk;
178 	int c, error;
179 	u_int maxdumppgs;
180 
181 	error = 0;	/* catch case in which chunk size is 0 */
182 	counter = 0;	/* Update twiddle every 16MB */
183 	va = NULL;
184 	pgs = mdp->pa_size / PAGE_SIZE;
185 	pa = mdp->pa_start;
186 	maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
187 	if (maxdumppgs == 0)	/* seatbelt */
188 		maxdumppgs = 1;
189 
190 	printf("  chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
191 	    (uintmax_t)pgs);
192 
193 	dumpsys_wbinv_all();
194 	while (pgs) {
195 		chunk = pgs;
196 		if (chunk > maxdumppgs)
197 			chunk = maxdumppgs;
198 		sz = chunk << PAGE_SHIFT;
199 		counter += sz;
200 		if (counter >> 24) {
201 			printf(" %ju", (uintmax_t)PG2MB(pgs));
202 			counter &= (1 << 24) - 1;
203 		}
204 
205 		dumpsys_map_chunk(pa, chunk, &va);
206 		wdog_kern_pat(WD_LASTVAL);
207 
208 		error = dump_append(di, va, 0, sz);
209 		dumpsys_unmap_chunk(pa, chunk, va);
210 		if (error)
211 			break;
212 		pgs -= chunk;
213 		pa += sz;
214 
215 		/* Check for user abort. */
216 		c = cncheckc();
217 		if (c == 0x03)
218 			return (ECANCELED);
219 		if (c != -1)
220 			printf(" (CTRL-C to abort) ");
221 	}
222 	printf(" ... %s\n", (error) ? "fail" : "ok");
223 	return (error);
224 }
225 
226 int
227 dumpsys_foreach_chunk(dumpsys_callback_t cb, void *arg)
228 {
229 	struct dump_pa *mdp;
230 	int error, seqnr;
231 
232 	seqnr = 0;
233 	mdp = dumpsys_pa_next(NULL);
234 	while (mdp != NULL) {
235 		error = (*cb)(mdp, seqnr++, arg);
236 		if (error)
237 			return (-error);
238 		mdp = dumpsys_pa_next(mdp);
239 	}
240 	return (seqnr);
241 }
242 
243 #if !defined(__sparc__)
244 static off_t fileofs;
245 
246 static int
247 cb_dumphdr(struct dump_pa *mdp, int seqnr, void *arg)
248 {
249 	struct dumperinfo *di = (struct dumperinfo*)arg;
250 	Elf_Phdr phdr;
251 	uint64_t size;
252 	int error;
253 
254 	size = mdp->pa_size;
255 	bzero(&phdr, sizeof(phdr));
256 	phdr.p_type = PT_LOAD;
257 	phdr.p_flags = PF_R;			/* XXX */
258 	phdr.p_offset = fileofs;
259 #ifdef __powerpc__
260 	phdr.p_vaddr = (do_minidump? mdp->pa_start : ~0L);
261 	phdr.p_paddr = (do_minidump? ~0L : mdp->pa_start);
262 #else
263 	phdr.p_vaddr = mdp->pa_start;
264 	phdr.p_paddr = mdp->pa_start;
265 #endif
266 	phdr.p_filesz = size;
267 	phdr.p_memsz = size;
268 	phdr.p_align = PAGE_SIZE;
269 
270 	error = dumpsys_buf_write(di, (char*)&phdr, sizeof(phdr));
271 	fileofs += phdr.p_filesz;
272 	return (error);
273 }
274 
275 static int
276 cb_size(struct dump_pa *mdp, int seqnr, void *arg)
277 {
278 	uint64_t *sz;
279 
280 	sz = (uint64_t *)arg;
281 	*sz += (uint64_t)mdp->pa_size;
282 	return (0);
283 }
284 
285 int
286 dumpsys_generic(struct dumperinfo *di)
287 {
288 	static struct kerneldumpheader kdh;
289 	Elf_Ehdr ehdr;
290 	uint64_t dumpsize;
291 	off_t hdrgap;
292 	size_t hdrsz;
293 	int error;
294 
295 #if !defined(__powerpc__) || defined(__powerpc64__)
296 	if (do_minidump)
297 		return (minidumpsys(di));
298 #endif
299 
300 	bzero(&ehdr, sizeof(ehdr));
301 	ehdr.e_ident[EI_MAG0] = ELFMAG0;
302 	ehdr.e_ident[EI_MAG1] = ELFMAG1;
303 	ehdr.e_ident[EI_MAG2] = ELFMAG2;
304 	ehdr.e_ident[EI_MAG3] = ELFMAG3;
305 	ehdr.e_ident[EI_CLASS] = ELF_CLASS;
306 #if BYTE_ORDER == LITTLE_ENDIAN
307 	ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
308 #else
309 	ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
310 #endif
311 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
312 	ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE;	/* XXX big picture? */
313 	ehdr.e_type = ET_CORE;
314 	ehdr.e_machine = EM_VALUE;
315 	ehdr.e_phoff = sizeof(ehdr);
316 	ehdr.e_flags = 0;
317 	ehdr.e_ehsize = sizeof(ehdr);
318 	ehdr.e_phentsize = sizeof(Elf_Phdr);
319 	ehdr.e_shentsize = sizeof(Elf_Shdr);
320 
321 	dumpsys_pa_init();
322 
323 	/* Calculate dump size. */
324 	dumpsize = 0L;
325 	ehdr.e_phnum = dumpsys_foreach_chunk(cb_size, &dumpsize) +
326 	    DUMPSYS_NUM_AUX_HDRS;
327 	hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
328 	fileofs = MD_ALIGN(hdrsz);
329 	dumpsize += fileofs;
330 	hdrgap = fileofs - roundup2((off_t)hdrsz, di->blocksize);
331 
332 	dump_init_header(di, &kdh, KERNELDUMPMAGIC, KERNELDUMP_ARCH_VERSION,
333 	    dumpsize);
334 
335 	error = dump_start(di, &kdh);
336 	if (error != 0)
337 		goto fail;
338 
339 	printf("Dumping %ju MB (%d chunks)\n", (uintmax_t)dumpsize >> 20,
340 	    ehdr.e_phnum - DUMPSYS_NUM_AUX_HDRS);
341 
342 	/* Dump ELF header */
343 	error = dumpsys_buf_write(di, (char*)&ehdr, sizeof(ehdr));
344 	if (error)
345 		goto fail;
346 
347 	/* Dump program headers */
348 	error = dumpsys_foreach_chunk(cb_dumphdr, di);
349 	if (error < 0)
350 		goto fail;
351 	error = dumpsys_write_aux_headers(di);
352 	if (error < 0)
353 		goto fail;
354 	dumpsys_buf_flush(di);
355 
356 	/*
357 	 * All headers are written using blocked I/O, so we know the
358 	 * current offset is (still) block aligned. Skip the alignement
359 	 * in the file to have the segment contents aligned at page
360 	 * boundary.
361 	 */
362 	error = dumpsys_buf_seek(di, (size_t)hdrgap);
363 	if (error)
364 		goto fail;
365 
366 	/* Dump memory chunks. */
367 	error = dumpsys_foreach_chunk(dumpsys_cb_dumpdata, di);
368 	if (error < 0)
369 		goto fail;
370 
371 	error = dump_finish(di, &kdh);
372 	if (error != 0)
373 		goto fail;
374 
375 	printf("\nDump complete\n");
376 	return (0);
377 
378  fail:
379 	if (error < 0)
380 		error = -error;
381 
382 	if (error == ECANCELED)
383 		printf("\nDump aborted\n");
384 	else if (error == E2BIG || error == ENOSPC)
385 		printf("\nDump failed. Partition too small.\n");
386 	else
387 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
388 	return (error);
389 }
390 #endif
391