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 * $FreeBSD: src/sys/amd64/amd64/dump_machdep.c,v 1.18 2009/05/29 21:27:12 jamie Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/conf.h> 32 #include <sys/cons.h> 33 #include <sys/sysctl.h> 34 #include <sys/device.h> 35 #include <sys/kernel.h> 36 #include <sys/kerneldump.h> 37 #include <vm/vm.h> 38 #include <vm/pmap.h> 39 #include <machine/elf.h> 40 #include <machine/md_var.h> 41 #include <machine/thread.h> 42 #include <sys/thread2.h> 43 44 CTASSERT(sizeof(struct kerneldumpheader) == 512); 45 46 int do_minidump = 1; 47 TUNABLE_INT("debug.minidump", &do_minidump); 48 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0, 49 "Enable mini crash dumps"); 50 51 /* 52 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This 53 * is to protect us from metadata and to protect metadata from us. 54 */ 55 #define SIZEOF_METADATA (64*1024) 56 57 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK) 58 #define DEV_ALIGN(x) (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1)) 59 60 struct md_pa { 61 vm_paddr_t md_start; 62 vm_paddr_t md_size; 63 }; 64 65 typedef int callback_t(struct md_pa *, int, void *); 66 67 static struct kerneldumpheader kdh; 68 static off_t dumplo, fileofs; 69 70 /* Handle buffered writes. */ 71 static char buffer[DEV_BSIZE]; 72 static size_t fragsz; 73 74 /* 20 phys_avail entry pairs correspond to 10 md_pa's */ 75 static struct md_pa dump_map[10]; 76 77 static void 78 md_pa_init(void) 79 { 80 int n, idx; 81 82 bzero(dump_map, sizeof(dump_map)); 83 for (n = 0; n < sizeof(dump_map) / sizeof(dump_map[0]); n++) { 84 idx = n * 2; 85 if (dump_avail[idx] == 0 && dump_avail[idx + 1] == 0) 86 break; 87 dump_map[n].md_start = dump_avail[idx]; 88 dump_map[n].md_size = dump_avail[idx + 1] - dump_avail[idx]; 89 } 90 } 91 92 static struct md_pa * 93 md_pa_first(void) 94 { 95 96 return (&dump_map[0]); 97 } 98 99 static struct md_pa * 100 md_pa_next(struct md_pa *mdp) 101 { 102 103 mdp++; 104 if (mdp->md_size == 0) 105 mdp = NULL; 106 return (mdp); 107 } 108 109 static int 110 buf_write(struct dumperinfo *di, char *ptr, size_t sz) 111 { 112 size_t len; 113 int error; 114 115 while (sz) { 116 len = DEV_BSIZE - fragsz; 117 if (len > sz) 118 len = sz; 119 bcopy(ptr, buffer + fragsz, len); 120 fragsz += len; 121 ptr += len; 122 sz -= len; 123 if (fragsz == DEV_BSIZE) { 124 error = dev_ddump(di->priv, buffer, 0, dumplo, 125 DEV_BSIZE); 126 if (error) 127 return error; 128 dumplo += DEV_BSIZE; 129 fragsz = 0; 130 } 131 } 132 133 return (0); 134 } 135 136 static int 137 buf_flush(struct dumperinfo *di) 138 { 139 int error; 140 141 if (fragsz == 0) 142 return (0); 143 144 error = dev_ddump(di->priv, buffer, 0, dumplo, DEV_BSIZE); 145 dumplo += DEV_BSIZE; 146 fragsz = 0; 147 return (error); 148 } 149 150 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8) 151 152 static int 153 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg) 154 { 155 struct dumperinfo *di = (struct dumperinfo*)arg; 156 vm_paddr_t a, pa; 157 void *va; 158 uint64_t pgs; 159 size_t counter, sz, chunk; 160 int i, c, error; 161 162 error = 0; /* catch case in which chunk size is 0 */ 163 counter = 0; /* Update twiddle every 16MB */ 164 va = 0; 165 pgs = mdp->md_size / PAGE_SIZE; 166 pa = mdp->md_start; 167 168 kprintf(" chunk %d: %ldMB (%ld pages)", seqnr, PG2MB(pgs), pgs); 169 170 while (pgs) { 171 chunk = pgs; 172 if (chunk > MAXDUMPPGS) 173 chunk = MAXDUMPPGS; 174 sz = chunk << PAGE_SHIFT; 175 counter += sz; 176 if (counter >> 24) { 177 kprintf(" %ld", PG2MB(pgs)); 178 counter &= (1<<24) - 1; 179 } 180 for (i = 0; i < chunk; i++) { 181 a = pa + i * PAGE_SIZE; 182 va = pmap_kenter_temporary(trunc_page(a), i); 183 } 184 error = dev_ddump(di->priv, va, 0, dumplo, sz); 185 if (error) 186 break; 187 dumplo += sz; 188 pgs -= chunk; 189 pa += sz; 190 191 /* Check for user abort. */ 192 c = cncheckc(); 193 if (c == 0x03) 194 return (ECANCELED); 195 if (c != -1) 196 kprintf(" (CTRL-C to abort) "); 197 } 198 kprintf(" ... %s\n", (error) ? "fail" : "ok"); 199 return (error); 200 } 201 202 static int 203 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg) 204 { 205 struct dumperinfo *di = (struct dumperinfo*)arg; 206 Elf_Phdr phdr; 207 uint64_t size; 208 int error; 209 210 size = mdp->md_size; 211 bzero(&phdr, sizeof(phdr)); 212 phdr.p_type = PT_LOAD; 213 phdr.p_flags = PF_R; /* XXX */ 214 phdr.p_offset = fileofs; 215 phdr.p_vaddr = mdp->md_start; 216 phdr.p_paddr = mdp->md_start; 217 phdr.p_filesz = size; 218 phdr.p_memsz = size; 219 phdr.p_align = PAGE_SIZE; 220 221 error = buf_write(di, (char*)&phdr, sizeof(phdr)); 222 fileofs += phdr.p_filesz; 223 return (error); 224 } 225 226 static int 227 cb_size(struct md_pa *mdp, int seqnr, void *arg) 228 { 229 uint64_t *sz = (uint64_t*)arg; 230 231 *sz += (uint64_t)mdp->md_size; 232 return (0); 233 } 234 235 static int 236 foreach_chunk(callback_t cb, void *arg) 237 { 238 struct md_pa *mdp; 239 int error, seqnr; 240 241 seqnr = 0; 242 mdp = md_pa_first(); 243 while (mdp != NULL) { 244 error = (*cb)(mdp, seqnr++, arg); 245 if (error) 246 return (-error); 247 mdp = md_pa_next(mdp); 248 } 249 return (seqnr); 250 } 251 252 void 253 md_dumpsys(struct dumperinfo *di) 254 { 255 Elf_Ehdr ehdr; 256 uint64_t dumpsize; 257 off_t hdrgap; 258 size_t hdrsz; 259 int error; 260 261 savectx(&dumppcb); 262 dumpthread = curthread; 263 264 if (do_minidump) { 265 minidumpsys(di); 266 return; 267 } 268 bzero(&ehdr, sizeof(ehdr)); 269 ehdr.e_ident[EI_MAG0] = ELFMAG0; 270 ehdr.e_ident[EI_MAG1] = ELFMAG1; 271 ehdr.e_ident[EI_MAG2] = ELFMAG2; 272 ehdr.e_ident[EI_MAG3] = ELFMAG3; 273 ehdr.e_ident[EI_CLASS] = ELF_CLASS; 274 #if BYTE_ORDER == LITTLE_ENDIAN 275 ehdr.e_ident[EI_DATA] = ELFDATA2LSB; 276 #else 277 ehdr.e_ident[EI_DATA] = ELFDATA2MSB; 278 #endif 279 ehdr.e_ident[EI_VERSION] = EV_CURRENT; 280 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */ 281 ehdr.e_type = ET_CORE; 282 ehdr.e_machine = EM_X86_64; 283 ehdr.e_phoff = sizeof(ehdr); 284 ehdr.e_flags = 0; 285 ehdr.e_ehsize = sizeof(ehdr); 286 ehdr.e_phentsize = sizeof(Elf_Phdr); 287 ehdr.e_shentsize = sizeof(Elf_Shdr); 288 289 md_pa_init(); 290 291 /* Calculate dump size. */ 292 dumpsize = 0L; 293 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize); 294 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize; 295 fileofs = MD_ALIGN(hdrsz); 296 dumpsize += fileofs; 297 hdrgap = fileofs - DEV_ALIGN(hdrsz); 298 299 /* Determine dump offset on device. */ 300 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) { 301 error = ENOSPC; 302 goto fail; 303 } 304 dumplo = di->mediaoffset + di->mediasize - dumpsize; 305 dumplo -= sizeof(kdh) * 2; 306 307 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION, 308 dumpsize, di->blocksize); 309 310 kprintf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20, 311 ehdr.e_phnum); 312 313 /* Dump leader */ 314 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 315 if (error) 316 goto fail; 317 dumplo += sizeof(kdh); 318 319 /* Dump ELF header */ 320 error = buf_write(di, (char*)&ehdr, sizeof(ehdr)); 321 if (error) 322 goto fail; 323 324 /* Dump program headers */ 325 error = foreach_chunk(cb_dumphdr, di); 326 if (error < 0) 327 goto fail; 328 buf_flush(di); 329 330 /* 331 * All headers are written using blocked I/O, so we know the 332 * current offset is (still) block aligned. Skip the alignement 333 * in the file to have the segment contents aligned at page 334 * boundary. We cannot use MD_ALIGN on dumplo, because we don't 335 * care and may very well be unaligned within the dump device. 336 */ 337 dumplo += hdrgap; 338 339 /* Dump memory chunks (updates dumplo) */ 340 error = foreach_chunk(cb_dumpdata, di); 341 if (error < 0) 342 goto fail; 343 344 /* Dump trailer */ 345 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 346 if (error) 347 goto fail; 348 349 /* Signal completion, signoff and exit stage left. */ 350 dev_ddump(di->priv, NULL, 0, 0, 0); 351 kprintf("\nDump complete\n"); 352 return; 353 354 fail: 355 if (error < 0) 356 error = -error; 357 358 if (error == ECANCELED) 359 kprintf("\nDump aborted\n"); 360 else if (error == ENOSPC) 361 kprintf("\nDump failed. Partition too small.\n"); 362 else 363 kprintf("\n** DUMP FAILED (ERROR %d) **\n", error); 364 } 365