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 <sys/kbio.h> 38 #include <vm/vm.h> 39 #include <vm/pmap.h> 40 #include <machine/elf.h> 41 #include <machine/md_var.h> 42 #include <machine/thread.h> 43 #include <machine/vmparam.h> 44 #include <sys/thread2.h> 45 46 CTASSERT(sizeof(struct kerneldumpheader) == 512); 47 48 int do_minidump = 1; 49 TUNABLE_INT("debug.minidump", &do_minidump); 50 SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RW, &do_minidump, 0, 51 "Enable mini crash dumps"); 52 53 /* 54 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This 55 * is to protect us from metadata and to protect metadata from us. 56 */ 57 #define SIZEOF_METADATA (64*1024) 58 59 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK) 60 #define DEV_ALIGN(x) roundup2((off_t)(x), DEV_BSIZE) 61 62 struct md_pa { 63 vm_paddr_t md_start; 64 vm_paddr_t md_size; 65 }; 66 67 typedef int callback_t(struct md_pa *, int, void *); 68 69 static struct kerneldumpheader kdh; 70 static off_t dumplo, fileofs; 71 72 /* Handle buffered writes. */ 73 static char buffer[DEV_BSIZE]; 74 static size_t fragsz; 75 76 static struct md_pa dump_map[VM_PHYSSEG_MAX+1]; 77 78 static void 79 md_pa_init(void) 80 { 81 int n; 82 83 bzero(dump_map, sizeof(dump_map)); 84 for (n = 0; n < NELEM(dump_map); n++) { 85 if (dump_avail[n].phys_beg == 0 && dump_avail[n].phys_end == 0) 86 break; 87 dump_map[n].md_start = dump_avail[n].phys_beg; 88 dump_map[n].md_size = dump_avail[n].phys_end - 89 dump_avail[n].phys_beg; 90 } 91 } 92 93 static struct md_pa * 94 md_pa_first(void) 95 { 96 97 return (&dump_map[0]); 98 } 99 100 static struct md_pa * 101 md_pa_next(struct md_pa *mdp) 102 { 103 104 mdp++; 105 if (mdp->md_size == 0) 106 mdp = NULL; 107 return (mdp); 108 } 109 110 static int 111 buf_write(struct dumperinfo *di, char *ptr, size_t sz) 112 { 113 size_t len; 114 int error; 115 116 while (sz) { 117 len = DEV_BSIZE - fragsz; 118 if (len > sz) 119 len = sz; 120 bcopy(ptr, buffer + fragsz, len); 121 fragsz += len; 122 ptr += len; 123 sz -= len; 124 if (fragsz == DEV_BSIZE) { 125 error = dev_ddump(di->priv, buffer, 0, dumplo, 126 DEV_BSIZE); 127 if (error) 128 return error; 129 dumplo += DEV_BSIZE; 130 fragsz = 0; 131 } 132 } 133 134 return (0); 135 } 136 137 static int 138 buf_flush(struct dumperinfo *di) 139 { 140 int error; 141 142 if (fragsz == 0) 143 return (0); 144 145 error = dev_ddump(di->priv, buffer, 0, dumplo, DEV_BSIZE); 146 dumplo += DEV_BSIZE; 147 fragsz = 0; 148 return (error); 149 } 150 151 #define PG2MB(pgs) ((pgs + (1 << 8) - 1) >> 8) 152 153 static int 154 cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg) 155 { 156 struct dumperinfo *di = (struct dumperinfo*)arg; 157 vm_paddr_t a, pa; 158 void *va; 159 uint64_t pgs; 160 size_t counter, sz, chunk; 161 int i, c, error; 162 int max_iosize; 163 164 error = 0; /* catch case in which chunk size is 0 */ 165 counter = 0; /* Update twiddle every 16MB */ 166 va = NULL; 167 pgs = mdp->md_size / PAGE_SIZE; 168 pa = mdp->md_start; 169 max_iosize = min(MAXPHYS, di->maxiosize); 170 171 kprintf(" chunk %d: %ldMB (%ld pages)", seqnr, PG2MB(pgs), pgs); 172 173 cnpoll(TRUE); 174 while (pgs) { 175 chunk = pgs; 176 if (chunk > (max_iosize/PAGE_SIZE)) 177 chunk = max_iosize/PAGE_SIZE; 178 sz = chunk << PAGE_SHIFT; 179 counter += sz; 180 if (counter >> 24) { 181 kprintf(" %ld", PG2MB(pgs)); 182 counter &= (1<<24) - 1; 183 } 184 for (i = 0; i < chunk; i++) { 185 a = pa + i * PAGE_SIZE; 186 va = pmap_kenter_temporary(trunc_page(a), i); 187 } 188 smp_invltlb(); 189 error = dev_ddump(di->priv, va, 0, dumplo, sz); 190 if (error) 191 break; 192 dumplo += sz; 193 pgs -= chunk; 194 pa += sz; 195 196 /* Check for user abort. */ 197 c = cncheckc(); 198 if (c == 0x03) { 199 error = ECANCELED; 200 goto done; 201 } 202 if (c != -1 && c != NOKEY) 203 kprintf(" (CTRL-C to abort) "); 204 } 205 kprintf(" ... %s\n", (error) ? "fail" : "ok"); 206 done: 207 cnpoll(FALSE); 208 return (error); 209 } 210 211 static int 212 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg) 213 { 214 struct dumperinfo *di = (struct dumperinfo*)arg; 215 Elf_Phdr phdr; 216 uint64_t size; 217 int error; 218 219 size = mdp->md_size; 220 bzero(&phdr, sizeof(phdr)); 221 phdr.p_type = PT_LOAD; 222 phdr.p_flags = PF_R; /* XXX */ 223 phdr.p_offset = fileofs; 224 phdr.p_vaddr = mdp->md_start; 225 phdr.p_paddr = mdp->md_start; 226 phdr.p_filesz = size; 227 phdr.p_memsz = size; 228 phdr.p_align = PAGE_SIZE; 229 230 error = buf_write(di, (char*)&phdr, sizeof(phdr)); 231 fileofs += phdr.p_filesz; 232 return (error); 233 } 234 235 static int 236 cb_size(struct md_pa *mdp, int seqnr, void *arg) 237 { 238 uint64_t *sz = (uint64_t*)arg; 239 240 *sz += (uint64_t)mdp->md_size; 241 return (0); 242 } 243 244 static int 245 foreach_chunk(callback_t cb, void *arg) 246 { 247 struct md_pa *mdp; 248 int error, seqnr; 249 250 seqnr = 0; 251 mdp = md_pa_first(); 252 while (mdp != NULL) { 253 error = (*cb)(mdp, seqnr++, arg); 254 if (error) 255 return (-error); 256 mdp = md_pa_next(mdp); 257 } 258 return (seqnr); 259 } 260 261 void 262 md_dumpsys(struct dumperinfo *di) 263 { 264 Elf_Ehdr ehdr; 265 uint64_t dumpsize; 266 off_t hdrgap; 267 size_t hdrsz; 268 int error; 269 270 /* 271 * Save context if dump called without panic. 272 */ 273 if (dumpthread == NULL) { 274 savectx(&dumppcb); 275 dumpthread = curthread; 276 } 277 278 if (do_minidump) { 279 minidumpsys(di); 280 return; 281 } 282 bzero(&ehdr, sizeof(ehdr)); 283 ehdr.e_ident[EI_MAG0] = ELFMAG0; 284 ehdr.e_ident[EI_MAG1] = ELFMAG1; 285 ehdr.e_ident[EI_MAG2] = ELFMAG2; 286 ehdr.e_ident[EI_MAG3] = ELFMAG3; 287 ehdr.e_ident[EI_CLASS] = ELF_CLASS; 288 #if BYTE_ORDER == LITTLE_ENDIAN 289 ehdr.e_ident[EI_DATA] = ELFDATA2LSB; 290 #else 291 ehdr.e_ident[EI_DATA] = ELFDATA2MSB; 292 #endif 293 ehdr.e_ident[EI_VERSION] = EV_CURRENT; 294 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */ 295 ehdr.e_type = ET_CORE; 296 ehdr.e_machine = EM_X86_64; 297 ehdr.e_phoff = sizeof(ehdr); 298 ehdr.e_flags = 0; 299 ehdr.e_ehsize = sizeof(ehdr); 300 ehdr.e_phentsize = sizeof(Elf_Phdr); 301 ehdr.e_shentsize = sizeof(Elf_Shdr); 302 303 md_pa_init(); 304 305 /* Calculate dump size. */ 306 dumpsize = 0L; 307 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize); 308 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize; 309 fileofs = MD_ALIGN(hdrsz); 310 dumpsize += fileofs; 311 hdrgap = fileofs - DEV_ALIGN(hdrsz); 312 313 /* Determine dump offset on device. */ 314 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) { 315 error = ENOSPC; 316 goto fail; 317 } 318 dumplo = di->mediaoffset + di->mediasize - dumpsize; 319 dumplo -= sizeof(kdh) * 2; 320 321 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION, 322 dumpsize, di->blocksize); 323 324 kprintf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20, 325 ehdr.e_phnum); 326 327 /* Dump leader */ 328 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 329 if (error) 330 goto fail; 331 dumplo += sizeof(kdh); 332 333 /* Dump ELF header */ 334 error = buf_write(di, (char*)&ehdr, sizeof(ehdr)); 335 if (error) 336 goto fail; 337 338 /* Dump program headers */ 339 error = foreach_chunk(cb_dumphdr, di); 340 if (error < 0) 341 goto fail; 342 buf_flush(di); 343 344 /* 345 * All headers are written using blocked I/O, so we know the 346 * current offset is (still) block aligned. Skip the alignement 347 * in the file to have the segment contents aligned at page 348 * boundary. We cannot use MD_ALIGN on dumplo, because we don't 349 * care and may very well be unaligned within the dump device. 350 */ 351 dumplo += hdrgap; 352 353 /* Dump memory chunks (updates dumplo) */ 354 error = foreach_chunk(cb_dumpdata, di); 355 if (error < 0) 356 goto fail; 357 358 /* Dump trailer */ 359 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 360 if (error) 361 goto fail; 362 363 /* Signal completion, signoff and exit stage left. */ 364 dev_ddump(di->priv, NULL, 0, 0, 0); 365 kprintf("\nDump complete\n"); 366 return; 367 368 fail: 369 if (error < 0) 370 error = -error; 371 372 if (error == ECANCELED) 373 kprintf("\nDump aborted\n"); 374 else if (error == ENOSPC) 375 kprintf("\nDump failed. Partition too small.\n"); 376 else 377 kprintf("\n** DUMP FAILED (ERROR %d) **\n", error); 378 } 379