xref: /freebsd/sys/kern/kern_dump.c (revision 6be3386466ab79a84b48429ae66244f21526d3df)
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/vm_dumpset.h>
43 #include <vm/pmap.h>
44 #include <machine/dump.h>
45 #include <machine/elf.h>
46 #include <machine/md_var.h>
47 #include <machine/pcb.h>
48 
49 CTASSERT(sizeof(struct kerneldumpheader) == 512);
50 
51 #define	MD_ALIGN(x)	roundup2((off_t)(x), PAGE_SIZE)
52 
53 /* Handle buffered writes. */
54 static size_t fragsz;
55 
56 struct dump_pa dump_map[DUMPSYS_MD_PA_NPAIRS];
57 
58 #if !defined(__powerpc__)
59 void
60 dumpsys_gen_pa_init(void)
61 {
62 	int n, idx;
63 
64 	bzero(dump_map, sizeof(dump_map));
65 	for (n = 0; n < nitems(dump_map); n++) {
66 		idx = n * 2;
67 		if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0)
68 			break;
69 		dump_map[n].pa_start = dump_avail[idx];
70 		dump_map[n].pa_size = dump_avail[idx + 1] - dump_avail[idx];
71 	}
72 }
73 #endif
74 
75 struct dump_pa *
76 dumpsys_gen_pa_next(struct dump_pa *mdp)
77 {
78 
79 	if (mdp == NULL)
80 		return (&dump_map[0]);
81 
82 	mdp++;
83 	if (mdp->pa_size == 0)
84 		mdp = NULL;
85 	return (mdp);
86 }
87 
88 void
89 dumpsys_gen_wbinv_all(void)
90 {
91 
92 }
93 
94 void
95 dumpsys_gen_unmap_chunk(vm_paddr_t pa __unused, size_t chunk __unused,
96     void *va __unused)
97 {
98 
99 }
100 
101 int
102 dumpsys_gen_write_aux_headers(struct dumperinfo *di)
103 {
104 
105 	return (0);
106 }
107 
108 int
109 dumpsys_buf_seek(struct dumperinfo *di, size_t sz)
110 {
111 	static uint8_t buf[DEV_BSIZE];
112 	size_t nbytes;
113 	int error;
114 
115 	bzero(buf, sizeof(buf));
116 
117 	while (sz > 0) {
118 		nbytes = MIN(sz, sizeof(buf));
119 
120 		error = dump_append(di, buf, 0, nbytes);
121 		if (error)
122 			return (error);
123 		sz -= nbytes;
124 	}
125 
126 	return (0);
127 }
128 
129 int
130 dumpsys_buf_write(struct dumperinfo *di, char *ptr, size_t sz)
131 {
132 	size_t len;
133 	int error;
134 
135 	while (sz) {
136 		len = di->blocksize - fragsz;
137 		if (len > sz)
138 			len = sz;
139 		memcpy((char *)di->blockbuf + fragsz, ptr, len);
140 		fragsz += len;
141 		ptr += len;
142 		sz -= len;
143 		if (fragsz == di->blocksize) {
144 			error = dump_append(di, di->blockbuf, 0, di->blocksize);
145 			if (error)
146 				return (error);
147 			fragsz = 0;
148 		}
149 	}
150 	return (0);
151 }
152 
153 int
154 dumpsys_buf_flush(struct dumperinfo *di)
155 {
156 	int error;
157 
158 	if (fragsz == 0)
159 		return (0);
160 
161 	error = dump_append(di, di->blockbuf, 0, di->blocksize);
162 	fragsz = 0;
163 	return (error);
164 }
165 
166 CTASSERT(PAGE_SHIFT < 20);
167 #define PG2MB(pgs) ((pgs + (1 << (20 - PAGE_SHIFT)) - 1) >> (20 - PAGE_SHIFT))
168 
169 int
170 dumpsys_cb_dumpdata(struct dump_pa *mdp, int seqnr, void *arg)
171 {
172 	struct dumperinfo *di = (struct dumperinfo*)arg;
173 	vm_paddr_t pa;
174 	void *va;
175 	uint64_t pgs;
176 	size_t counter, sz, chunk;
177 	int c, error;
178 	u_int maxdumppgs;
179 
180 	error = 0;	/* catch case in which chunk size is 0 */
181 	counter = 0;	/* Update twiddle every 16MB */
182 	va = NULL;
183 	pgs = mdp->pa_size / PAGE_SIZE;
184 	pa = mdp->pa_start;
185 	maxdumppgs = min(di->maxiosize / PAGE_SIZE, MAXDUMPPGS);
186 	if (maxdumppgs == 0)	/* seatbelt */
187 		maxdumppgs = 1;
188 
189 	printf("  chunk %d: %juMB (%ju pages)", seqnr, (uintmax_t)PG2MB(pgs),
190 	    (uintmax_t)pgs);
191 
192 	dumpsys_wbinv_all();
193 	while (pgs) {
194 		chunk = pgs;
195 		if (chunk > maxdumppgs)
196 			chunk = maxdumppgs;
197 		sz = chunk << PAGE_SHIFT;
198 		counter += sz;
199 		if (counter >> 24) {
200 			printf(" %ju", (uintmax_t)PG2MB(pgs));
201 			counter &= (1 << 24) - 1;
202 		}
203 
204 		dumpsys_map_chunk(pa, chunk, &va);
205 		wdog_kern_pat(WD_LASTVAL);
206 
207 		error = dump_append(di, va, 0, sz);
208 		dumpsys_unmap_chunk(pa, chunk, va);
209 		if (error)
210 			break;
211 		pgs -= chunk;
212 		pa += sz;
213 
214 		/* Check for user abort. */
215 		c = cncheckc();
216 		if (c == 0x03)
217 			return (ECANCELED);
218 		if (c != -1)
219 			printf(" (CTRL-C to abort) ");
220 	}
221 	printf(" ... %s\n", (error) ? "fail" : "ok");
222 	return (error);
223 }
224 
225 int
226 dumpsys_foreach_chunk(dumpsys_callback_t cb, void *arg)
227 {
228 	struct dump_pa *mdp;
229 	int error, seqnr;
230 
231 	seqnr = 0;
232 	mdp = dumpsys_pa_next(NULL);
233 	while (mdp != NULL) {
234 		error = (*cb)(mdp, seqnr++, arg);
235 		if (error)
236 			return (-error);
237 		mdp = dumpsys_pa_next(mdp);
238 	}
239 	return (seqnr);
240 }
241 
242 static off_t fileofs;
243 
244 static int
245 cb_dumphdr(struct dump_pa *mdp, int seqnr, void *arg)
246 {
247 	struct dumperinfo *di = (struct dumperinfo*)arg;
248 	Elf_Phdr phdr;
249 	uint64_t size;
250 	int error;
251 
252 	size = mdp->pa_size;
253 	bzero(&phdr, sizeof(phdr));
254 	phdr.p_type = PT_LOAD;
255 	phdr.p_flags = PF_R;			/* XXX */
256 	phdr.p_offset = fileofs;
257 #ifdef __powerpc__
258 	phdr.p_vaddr = (do_minidump? mdp->pa_start : ~0L);
259 	phdr.p_paddr = (do_minidump? ~0L : mdp->pa_start);
260 #else
261 	phdr.p_vaddr = mdp->pa_start;
262 	phdr.p_paddr = mdp->pa_start;
263 #endif
264 	phdr.p_filesz = size;
265 	phdr.p_memsz = size;
266 	phdr.p_align = PAGE_SIZE;
267 
268 	error = dumpsys_buf_write(di, (char*)&phdr, sizeof(phdr));
269 	fileofs += phdr.p_filesz;
270 	return (error);
271 }
272 
273 static int
274 cb_size(struct dump_pa *mdp, int seqnr, void *arg)
275 {
276 	uint64_t *sz;
277 
278 	sz = (uint64_t *)arg;
279 	*sz += (uint64_t)mdp->pa_size;
280 	return (0);
281 }
282 
283 int
284 dumpsys_generic(struct dumperinfo *di)
285 {
286 	static struct kerneldumpheader kdh;
287 	Elf_Ehdr ehdr;
288 	uint64_t dumpsize;
289 	off_t hdrgap;
290 	size_t hdrsz;
291 	int error;
292 
293 #if MINIDUMP_PAGE_TRACKING == 1
294 	if (do_minidump)
295 		return (minidumpsys(di));
296 #endif
297 
298 	bzero(&ehdr, sizeof(ehdr));
299 	ehdr.e_ident[EI_MAG0] = ELFMAG0;
300 	ehdr.e_ident[EI_MAG1] = ELFMAG1;
301 	ehdr.e_ident[EI_MAG2] = ELFMAG2;
302 	ehdr.e_ident[EI_MAG3] = ELFMAG3;
303 	ehdr.e_ident[EI_CLASS] = ELF_CLASS;
304 #if BYTE_ORDER == LITTLE_ENDIAN
305 	ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
306 #else
307 	ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
308 #endif
309 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
310 	ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE;	/* XXX big picture? */
311 	ehdr.e_type = ET_CORE;
312 	ehdr.e_machine = EM_VALUE;
313 	ehdr.e_phoff = sizeof(ehdr);
314 	ehdr.e_flags = 0;
315 	ehdr.e_ehsize = sizeof(ehdr);
316 	ehdr.e_phentsize = sizeof(Elf_Phdr);
317 	ehdr.e_shentsize = sizeof(Elf_Shdr);
318 
319 	dumpsys_pa_init();
320 
321 	/* Calculate dump size. */
322 	dumpsize = 0L;
323 	ehdr.e_phnum = dumpsys_foreach_chunk(cb_size, &dumpsize) +
324 	    DUMPSYS_NUM_AUX_HDRS;
325 	hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
326 	fileofs = MD_ALIGN(hdrsz);
327 	dumpsize += fileofs;
328 	hdrgap = fileofs - roundup2((off_t)hdrsz, di->blocksize);
329 
330 	dump_init_header(di, &kdh, KERNELDUMPMAGIC, KERNELDUMP_ARCH_VERSION,
331 	    dumpsize);
332 
333 	error = dump_start(di, &kdh);
334 	if (error != 0)
335 		goto fail;
336 
337 	printf("Dumping %ju MB (%d chunks)\n", (uintmax_t)dumpsize >> 20,
338 	    ehdr.e_phnum - DUMPSYS_NUM_AUX_HDRS);
339 
340 	/* Dump ELF header */
341 	error = dumpsys_buf_write(di, (char*)&ehdr, sizeof(ehdr));
342 	if (error)
343 		goto fail;
344 
345 	/* Dump program headers */
346 	error = dumpsys_foreach_chunk(cb_dumphdr, di);
347 	if (error < 0)
348 		goto fail;
349 	error = dumpsys_write_aux_headers(di);
350 	if (error < 0)
351 		goto fail;
352 	dumpsys_buf_flush(di);
353 
354 	/*
355 	 * All headers are written using blocked I/O, so we know the
356 	 * current offset is (still) block aligned. Skip the alignement
357 	 * in the file to have the segment contents aligned at page
358 	 * boundary.
359 	 */
360 	error = dumpsys_buf_seek(di, (size_t)hdrgap);
361 	if (error)
362 		goto fail;
363 
364 	/* Dump memory chunks. */
365 	error = dumpsys_foreach_chunk(dumpsys_cb_dumpdata, di);
366 	if (error < 0)
367 		goto fail;
368 
369 	error = dump_finish(di, &kdh);
370 	if (error != 0)
371 		goto fail;
372 
373 	printf("\nDump complete\n");
374 	return (0);
375 
376  fail:
377 	if (error < 0)
378 		error = -error;
379 
380 	if (error == ECANCELED)
381 		printf("\nDump aborted\n");
382 	else if (error == E2BIG || error == ENOSPC)
383 		printf("\nDump failed. Partition too small.\n");
384 	else
385 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
386 	return (error);
387 }
388