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