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 < NELEM(dump_map); 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 smp_invltlb(); 185 error = dev_ddump(di->priv, va, 0, dumplo, sz); 186 if (error) 187 break; 188 dumplo += sz; 189 pgs -= chunk; 190 pa += sz; 191 192 /* Check for user abort. */ 193 c = cncheckc(); 194 if (c == 0x03) 195 return (ECANCELED); 196 if (c != -1) 197 kprintf(" (CTRL-C to abort) "); 198 } 199 kprintf(" ... %s\n", (error) ? "fail" : "ok"); 200 return (error); 201 } 202 203 static int 204 cb_dumphdr(struct md_pa *mdp, int seqnr, void *arg) 205 { 206 struct dumperinfo *di = (struct dumperinfo*)arg; 207 Elf_Phdr phdr; 208 uint64_t size; 209 int error; 210 211 size = mdp->md_size; 212 bzero(&phdr, sizeof(phdr)); 213 phdr.p_type = PT_LOAD; 214 phdr.p_flags = PF_R; /* XXX */ 215 phdr.p_offset = fileofs; 216 phdr.p_vaddr = mdp->md_start; 217 phdr.p_paddr = mdp->md_start; 218 phdr.p_filesz = size; 219 phdr.p_memsz = size; 220 phdr.p_align = PAGE_SIZE; 221 222 error = buf_write(di, (char*)&phdr, sizeof(phdr)); 223 fileofs += phdr.p_filesz; 224 return (error); 225 } 226 227 static int 228 cb_size(struct md_pa *mdp, int seqnr, void *arg) 229 { 230 uint64_t *sz = (uint64_t*)arg; 231 232 *sz += (uint64_t)mdp->md_size; 233 return (0); 234 } 235 236 static int 237 foreach_chunk(callback_t cb, void *arg) 238 { 239 struct md_pa *mdp; 240 int error, seqnr; 241 242 seqnr = 0; 243 mdp = md_pa_first(); 244 while (mdp != NULL) { 245 error = (*cb)(mdp, seqnr++, arg); 246 if (error) 247 return (-error); 248 mdp = md_pa_next(mdp); 249 } 250 return (seqnr); 251 } 252 253 void 254 md_dumpsys(struct dumperinfo *di) 255 { 256 Elf_Ehdr ehdr; 257 uint64_t dumpsize; 258 off_t hdrgap; 259 size_t hdrsz; 260 int error; 261 262 savectx(&dumppcb); 263 dumpthread = curthread; 264 265 if (do_minidump) { 266 minidumpsys(di); 267 return; 268 } 269 bzero(&ehdr, sizeof(ehdr)); 270 ehdr.e_ident[EI_MAG0] = ELFMAG0; 271 ehdr.e_ident[EI_MAG1] = ELFMAG1; 272 ehdr.e_ident[EI_MAG2] = ELFMAG2; 273 ehdr.e_ident[EI_MAG3] = ELFMAG3; 274 ehdr.e_ident[EI_CLASS] = ELF_CLASS; 275 #if BYTE_ORDER == LITTLE_ENDIAN 276 ehdr.e_ident[EI_DATA] = ELFDATA2LSB; 277 #else 278 ehdr.e_ident[EI_DATA] = ELFDATA2MSB; 279 #endif 280 ehdr.e_ident[EI_VERSION] = EV_CURRENT; 281 ehdr.e_ident[EI_OSABI] = ELFOSABI_STANDALONE; /* XXX big picture? */ 282 ehdr.e_type = ET_CORE; 283 ehdr.e_machine = EM_X86_64; 284 ehdr.e_phoff = sizeof(ehdr); 285 ehdr.e_flags = 0; 286 ehdr.e_ehsize = sizeof(ehdr); 287 ehdr.e_phentsize = sizeof(Elf_Phdr); 288 ehdr.e_shentsize = sizeof(Elf_Shdr); 289 290 md_pa_init(); 291 292 /* Calculate dump size. */ 293 dumpsize = 0L; 294 ehdr.e_phnum = foreach_chunk(cb_size, &dumpsize); 295 hdrsz = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize; 296 fileofs = MD_ALIGN(hdrsz); 297 dumpsize += fileofs; 298 hdrgap = fileofs - DEV_ALIGN(hdrsz); 299 300 /* Determine dump offset on device. */ 301 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) { 302 error = ENOSPC; 303 goto fail; 304 } 305 dumplo = di->mediaoffset + di->mediasize - dumpsize; 306 dumplo -= sizeof(kdh) * 2; 307 308 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION, 309 dumpsize, di->blocksize); 310 311 kprintf("Dumping %llu MB (%d chunks)\n", (long long)dumpsize >> 20, 312 ehdr.e_phnum); 313 314 /* Dump leader */ 315 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 316 if (error) 317 goto fail; 318 dumplo += sizeof(kdh); 319 320 /* Dump ELF header */ 321 error = buf_write(di, (char*)&ehdr, sizeof(ehdr)); 322 if (error) 323 goto fail; 324 325 /* Dump program headers */ 326 error = foreach_chunk(cb_dumphdr, di); 327 if (error < 0) 328 goto fail; 329 buf_flush(di); 330 331 /* 332 * All headers are written using blocked I/O, so we know the 333 * current offset is (still) block aligned. Skip the alignement 334 * in the file to have the segment contents aligned at page 335 * boundary. We cannot use MD_ALIGN on dumplo, because we don't 336 * care and may very well be unaligned within the dump device. 337 */ 338 dumplo += hdrgap; 339 340 /* Dump memory chunks (updates dumplo) */ 341 error = foreach_chunk(cb_dumpdata, di); 342 if (error < 0) 343 goto fail; 344 345 /* Dump trailer */ 346 error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh)); 347 if (error) 348 goto fail; 349 350 /* Signal completion, signoff and exit stage left. */ 351 dev_ddump(di->priv, NULL, 0, 0, 0); 352 kprintf("\nDump complete\n"); 353 return; 354 355 fail: 356 if (error < 0) 357 error = -error; 358 359 if (error == ECANCELED) 360 kprintf("\nDump aborted\n"); 361 else if (error == ENOSPC) 362 kprintf("\nDump failed. Partition too small.\n"); 363 else 364 kprintf("\n** DUMP FAILED (ERROR %d) **\n", error); 365 } 366