xref: /freebsd/sys/powerpc/powerpc/dump_machdep.c (revision 195ebc7e9e4b129de810833791a19dfb4349d6a9)
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/kerneldump.h>
36 #include <sys/sysctl.h>
37 #include <vm/vm.h>
38 #include <vm/pmap.h>
39 #include <machine/elf.h>
40 #include <machine/md_var.h>
41 
42 CTASSERT(sizeof(struct kerneldumpheader) == 512);
43 
44 /*
45  * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
46  * is to protect us from metadata and to protect metadata from us.
47  */
48 #define	SIZEOF_METADATA		(64*1024)
49 
50 #define	MD_ALIGN(x)	(((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
51 #define	DEV_ALIGN(x)	(((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
52 
53 typedef int callback_t(struct pmap_md *, int, void *);
54 
55 static struct kerneldumpheader kdh;
56 static off_t dumplo, fileofs;
57 
58 /* Handle buffered writes. */
59 static char buffer[DEV_BSIZE];
60 static size_t fragsz;
61 
62 int dumpsys_minidump = 1;
63 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RD, &dumpsys_minidump, 0,
64     "Kernel makes compressed crash dumps");
65 
66 static int
67 buf_write(struct dumperinfo *di, char *ptr, size_t sz)
68 {
69 	size_t len;
70 	int error;
71 
72 	while (sz) {
73 		len = DEV_BSIZE - fragsz;
74 		if (len > sz)
75 			len = sz;
76 		bcopy(ptr, buffer + fragsz, len);
77 		fragsz += len;
78 		ptr += len;
79 		sz -= len;
80 		if (fragsz == DEV_BSIZE) {
81 			error = di->dumper(di->priv, buffer, 0, dumplo,
82 			    DEV_BSIZE);
83 			if (error)
84 				return error;
85 			dumplo += DEV_BSIZE;
86 			fragsz = 0;
87 		}
88 	}
89 
90 	return (0);
91 }
92 
93 static int
94 buf_flush(struct dumperinfo *di)
95 {
96 	int error;
97 
98 	if (fragsz == 0)
99 		return (0);
100 
101 	error = di->dumper(di->priv, buffer, 0, dumplo, DEV_BSIZE);
102 	dumplo += DEV_BSIZE;
103 	fragsz = 0;
104 	return (error);
105 }
106 
107 static int
108 cb_dumpdata(struct pmap_md *md, int seqnr, void *arg)
109 {
110 	struct dumperinfo *di = (struct dumperinfo*)arg;
111 	vm_offset_t va;
112 	size_t counter, ofs, resid, sz;
113 	int c, error, twiddle;
114 
115 	error = 0;
116 	counter = 0;	/* Update twiddle every 16MB */
117 	twiddle = 0;
118 
119 	ofs = 0;	/* Logical offset within the chunk */
120 	resid = md->md_size;
121 
122 	printf("  chunk %d: %lu bytes ", seqnr, (u_long)resid);
123 
124 	while (resid) {
125 		sz = (resid > DFLTPHYS) ? DFLTPHYS : resid;
126 		va = pmap_dumpsys_map(md, ofs, &sz);
127 		counter += sz;
128 		if (counter >> 24) {
129 			printf("%c\b", "|/-\\"[twiddle++ & 3]);
130 			counter &= (1<<24) - 1;
131 		}
132 		error = di->dumper(di->priv, (void*)va, 0, dumplo, sz);
133 		pmap_dumpsys_unmap(md, ofs, va);
134 		if (error)
135 			break;
136 		dumplo += sz;
137 		resid -= sz;
138 		ofs += sz;
139 
140 		/* Check for user abort. */
141 		c = cncheckc();
142 		if (c == 0x03)
143 			return (ECANCELED);
144 		if (c != -1)
145 			printf("(CTRL-C to abort)  ");
146 	}
147 	printf("... %s\n", (error) ? "fail" : "ok");
148 	return (error);
149 }
150 
151 static int
152 cb_dumphdr(struct pmap_md *md, int seqnr, void *arg)
153 {
154 	struct dumperinfo *di = (struct dumperinfo*)arg;
155 	Elf32_Phdr phdr;
156 	int error;
157 
158 	bzero(&phdr, sizeof(phdr));
159 	phdr.p_type = PT_LOAD;
160 	phdr.p_flags = PF_R;			/* XXX */
161 	phdr.p_offset = fileofs;
162 	phdr.p_vaddr = md->md_vaddr;
163 	phdr.p_paddr = md->md_paddr;
164 	phdr.p_filesz = md->md_size;
165 	phdr.p_memsz = md->md_size;
166 	phdr.p_align = PAGE_SIZE;
167 
168 	error = buf_write(di, (char*)&phdr, sizeof(phdr));
169 	fileofs += phdr.p_filesz;
170 	return (error);
171 }
172 
173 static int
174 cb_size(struct pmap_md *md, int seqnr, void *arg)
175 {
176 	uint32_t *sz = (uint32_t*)arg;
177 
178 	*sz += md->md_size;
179 	return (0);
180 }
181 
182 static int
183 foreach_chunk(callback_t cb, void *arg)
184 {
185 	struct pmap_md *md;
186 	int error, seqnr;
187 
188 	seqnr = 0;
189 	md = pmap_scan_md(NULL);
190 	while (md != NULL) {
191 		error = (*cb)(md, seqnr++, arg);
192 		if (error)
193 			return (-error);
194 		md = pmap_scan_md(md);
195 	}
196 	return (seqnr);
197 }
198 
199 void
200 dumpsys(struct dumperinfo *di)
201 {
202 	Elf32_Ehdr ehdr;
203 	uint32_t dumpsize;
204 	off_t hdrgap;
205 	size_t hdrsz;
206 	int error;
207 
208 	bzero(&ehdr, sizeof(ehdr));
209 	ehdr.e_ident[EI_MAG0] = ELFMAG0;
210 	ehdr.e_ident[EI_MAG1] = ELFMAG1;
211 	ehdr.e_ident[EI_MAG2] = ELFMAG2;
212 	ehdr.e_ident[EI_MAG3] = ELFMAG3;
213 	ehdr.e_ident[EI_CLASS] = ELFCLASS32;
214 #if BYTE_ORDER == LITTLE_ENDIAN
215 	ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
216 #else
217 	ehdr.e_ident[EI_DATA] = ELFDATA2MSB;
218 #endif
219 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
220 	ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE;	/* XXX big picture? */
221 	ehdr.e_type = ET_CORE;
222 	ehdr.e_machine = EM_PPC;
223 	ehdr.e_phoff = sizeof(ehdr);
224 	ehdr.e_ehsize = sizeof(ehdr);
225 	ehdr.e_phentsize = sizeof(Elf32_Phdr);
226 	ehdr.e_shentsize = sizeof(Elf32_Shdr);
227 
228 	/* Calculate dump size. */
229 	dumpsize = 0L;
230 	ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize);
231 	hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
232 	fileofs = MD_ALIGN(hdrsz);
233 	dumpsize += fileofs;
234 	hdrgap = fileofs - DEV_ALIGN(hdrsz);
235 
236 	/* For block devices, determine the dump offset on the device. */
237 	if (di->mediasize > 0) {
238 		if (di->mediasize <
239 		    SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
240 			error = ENOSPC;
241 			goto fail;
242 		}
243 		dumplo = di->mediaoffset + di->mediasize - dumpsize;
244 		dumplo -= sizeof(kdh) * 2;
245 	} else
246 		dumplo = 0;
247 
248 	mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_POWERPC_VERSION, dumpsize,
249 	    di->blocksize);
250 
251 	printf("Dumping %u MB (%d chunks)\n", dumpsize >> 20,
252 	    ehdr.e_phnum);
253 
254 	/* Dump leader */
255 	error = di->dumper(di->priv, &kdh, 0, dumplo, sizeof(kdh));
256 	if (error)
257 		goto fail;
258 	dumplo += sizeof(kdh);
259 
260 	/* Dump ELF header */
261 	error = buf_write(di, (char*)&ehdr, sizeof(ehdr));
262 	if (error)
263 		goto fail;
264 
265 	/* Dump program headers */
266 	error = foreach_chunk(cb_dumphdr, di);
267 	if (error < 0)
268 		goto fail;
269 	buf_flush(di);
270 
271 	/*
272 	 * All headers are written using blocked I/O, so we know the
273 	 * current offset is (still) block aligned. Skip the alignement
274 	 * in the file to have the segment contents aligned at page
275 	 * boundary. We cannot use MD_ALIGN on dumplo, because we don't
276 	 * care and may very well be unaligned within the dump device.
277 	 */
278 	dumplo += hdrgap;
279 
280 	/* Dump memory chunks (updates dumplo) */
281 	error = foreach_chunk(cb_dumpdata, di);
282 	if (error < 0)
283 		goto fail;
284 
285 	/* Dump trailer */
286 	error = di->dumper(di->priv, &kdh, 0, dumplo, sizeof(kdh));
287 	if (error)
288 		goto fail;
289 
290 	/* Signal completion, signoff and exit stage left. */
291 	di->dumper(di->priv, NULL, 0, 0, 0);
292 	printf("\nDump complete\n");
293 	return;
294 
295  fail:
296 	if (error < 0)
297 		error = -error;
298 
299 	if (error == ECANCELED)
300 		printf("\nDump aborted\n");
301 	else
302 		printf("\n** DUMP FAILED (ERROR %d) **\n", error);
303 }
304