minidump_machdep.c revision 305780
1/*- 2 * Copyright (c) 2006 Peter Wemm 3 * Copyright (c) 2008 Semihalf, Grzegorz Bernacki 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * from: FreeBSD: src/sys/i386/i386/minidump_machdep.c,v 1.6 2008/08/17 23:27:27 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD: stable/11/sys/arm/arm/minidump_machdep.c 305780 2016-09-13 19:56:34Z markj $"); 32 33#include "opt_watchdog.h" 34 35#include <sys/param.h> 36#include <sys/systm.h> 37#include <sys/conf.h> 38#include <sys/cons.h> 39#include <sys/kernel.h> 40#include <sys/kerneldump.h> 41#include <sys/msgbuf.h> 42#ifdef SW_WATCHDOG 43#include <sys/watchdog.h> 44#endif 45#include <vm/vm.h> 46#include <vm/pmap.h> 47#include <machine/atomic.h> 48#include <machine/cpu.h> 49#include <machine/elf.h> 50#include <machine/md_var.h> 51#include <machine/minidump.h> 52#include <machine/vmparam.h> 53 54CTASSERT(sizeof(struct kerneldumpheader) == 512); 55 56/* 57 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This 58 * is to protect us from metadata and to protect metadata from us. 59 */ 60#define SIZEOF_METADATA (64*1024) 61 62uint32_t *vm_page_dump; 63int vm_page_dump_size; 64 65static struct kerneldumpheader kdh; 66 67static off_t dumplo; 68 69/* Handle chunked writes. */ 70static size_t fragsz; 71static void *dump_va; 72static uint64_t counter, progress; 73 74CTASSERT(sizeof(*vm_page_dump) == 4); 75 76static int 77is_dumpable(vm_paddr_t pa) 78{ 79 int i; 80 81 for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) { 82 if (pa >= dump_avail[i] && pa < dump_avail[i + 1]) 83 return (1); 84 } 85 return (0); 86} 87 88#define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8) 89 90static int 91blk_flush(struct dumperinfo *di) 92{ 93 int error; 94 95 if (fragsz == 0) 96 return (0); 97 98 error = dump_write(di, dump_va, 0, dumplo, fragsz); 99 dumplo += fragsz; 100 fragsz = 0; 101 return (error); 102} 103 104static int 105blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz) 106{ 107 size_t len; 108 int error, i, c; 109 u_int maxdumpsz; 110 111 maxdumpsz = min(di->maxiosize, MAXDUMPPGS * PAGE_SIZE); 112 if (maxdumpsz == 0) /* seatbelt */ 113 maxdumpsz = PAGE_SIZE; 114 error = 0; 115 if (ptr != NULL && pa != 0) { 116 printf("cant have both va and pa!\n"); 117 return (EINVAL); 118 } 119 if (pa != 0) { 120 if ((sz % PAGE_SIZE) != 0) { 121 printf("size not page aligned\n"); 122 return (EINVAL); 123 } 124 if ((pa & PAGE_MASK) != 0) { 125 printf("address not page aligned\n"); 126 return (EINVAL); 127 } 128 } 129 if (ptr != NULL) { 130 /* Flush any pre-existing pa pages before a virtual dump. */ 131 error = blk_flush(di); 132 if (error) 133 return (error); 134 } 135 while (sz) { 136 len = maxdumpsz - fragsz; 137 if (len > sz) 138 len = sz; 139 counter += len; 140 progress -= len; 141 if (counter >> 22) { 142 printf(" %lld", PG2MB(progress >> PAGE_SHIFT)); 143 counter &= (1<<22) - 1; 144 } 145 146#ifdef SW_WATCHDOG 147 wdog_kern_pat(WD_LASTVAL); 148#endif 149 if (ptr) { 150 error = dump_write(di, ptr, 0, dumplo, len); 151 if (error) 152 return (error); 153 dumplo += len; 154 ptr += len; 155 sz -= len; 156 } else { 157 for (i = 0; i < len; i += PAGE_SIZE) 158 dump_va = pmap_kenter_temporary(pa + i, 159 (i + fragsz) >> PAGE_SHIFT); 160 fragsz += len; 161 pa += len; 162 sz -= len; 163 if (fragsz == maxdumpsz) { 164 error = blk_flush(di); 165 if (error) 166 return (error); 167 } 168 } 169 170 /* Check for user abort. */ 171 c = cncheckc(); 172 if (c == 0x03) 173 return (ECANCELED); 174 if (c != -1) 175 printf(" (CTRL-C to abort) "); 176 } 177 178 return (0); 179} 180 181/* A buffer for general use. Its size must be one page at least. */ 182static char dumpbuf[PAGE_SIZE]; 183CTASSERT(sizeof(dumpbuf) % sizeof(pt2_entry_t) == 0); 184 185int 186minidumpsys(struct dumperinfo *di) 187{ 188 struct minidumphdr mdhdr; 189 uint64_t dumpsize; 190 uint32_t ptesize; 191 uint32_t bits; 192 uint32_t pa, prev_pa = 0, count = 0; 193 vm_offset_t va; 194 int i, bit, error; 195 char *addr; 196 197 /* 198 * Flush caches. Note that in the SMP case this operates only on the 199 * current CPU's L1 cache. Before we reach this point, code in either 200 * the system shutdown or kernel debugger has called stop_cpus() to stop 201 * all cores other than this one. Part of the ARM handling of 202 * stop_cpus() is to call wbinv_all() on that core's local L1 cache. So 203 * by time we get to here, all that remains is to flush the L1 for the 204 * current CPU, then the L2. 205 */ 206 dcache_wbinv_poc_all(); 207 208 counter = 0; 209 /* Walk page table pages, set bits in vm_page_dump */ 210 ptesize = 0; 211 for (va = KERNBASE; va < kernel_vm_end; va += PAGE_SIZE) { 212 pa = pmap_dump_kextract(va, NULL); 213 if (pa != 0 && is_dumpable(pa)) 214 dump_add_page(pa); 215 ptesize += sizeof(pt2_entry_t); 216 } 217 218 /* Calculate dump size. */ 219 dumpsize = ptesize; 220 dumpsize += round_page(msgbufp->msg_size); 221 dumpsize += round_page(vm_page_dump_size); 222 223 for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) { 224 bits = vm_page_dump[i]; 225 while (bits) { 226 bit = ffs(bits) - 1; 227 pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + 228 bit) * PAGE_SIZE; 229 /* Clear out undumpable pages now if needed */ 230 if (is_dumpable(pa)) 231 dumpsize += PAGE_SIZE; 232 else 233 dump_drop_page(pa); 234 bits &= ~(1ul << bit); 235 } 236 } 237 238 dumpsize += PAGE_SIZE; 239 240 /* Determine dump offset on device. */ 241 if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) { 242 error = ENOSPC; 243 goto fail; 244 } 245 246 dumplo = di->mediaoffset + di->mediasize - dumpsize; 247 dumplo -= sizeof(kdh) * 2; 248 progress = dumpsize; 249 250 /* Initialize mdhdr */ 251 bzero(&mdhdr, sizeof(mdhdr)); 252 strcpy(mdhdr.magic, MINIDUMP_MAGIC); 253 mdhdr.version = MINIDUMP_VERSION; 254 mdhdr.msgbufsize = msgbufp->msg_size; 255 mdhdr.bitmapsize = vm_page_dump_size; 256 mdhdr.ptesize = ptesize; 257 mdhdr.kernbase = KERNBASE; 258 mdhdr.arch = __ARM_ARCH; 259#if __ARM_ARCH >= 6 260 mdhdr.mmuformat = MINIDUMP_MMU_FORMAT_V6; 261#else 262 mdhdr.mmuformat = MINIDUMP_MMU_FORMAT_V4; 263#endif 264 mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_ARM_VERSION, dumpsize, 265 di->blocksize); 266 267 printf("Physical memory: %u MB\n", ptoa((uintmax_t)physmem) / 1048576); 268 printf("Dumping %llu MB:", (long long)dumpsize >> 20); 269 270 /* Dump leader */ 271 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh)); 272 if (error) 273 goto fail; 274 dumplo += sizeof(kdh); 275 276 /* Dump my header */ 277 bzero(dumpbuf, sizeof(dumpbuf)); 278 bcopy(&mdhdr, dumpbuf, sizeof(mdhdr)); 279 error = blk_write(di, dumpbuf, 0, PAGE_SIZE); 280 if (error) 281 goto fail; 282 283 /* Dump msgbuf up front */ 284 error = blk_write(di, (char *)msgbufp->msg_ptr, 0, 285 round_page(msgbufp->msg_size)); 286 if (error) 287 goto fail; 288 289 /* Dump bitmap */ 290 error = blk_write(di, (char *)vm_page_dump, 0, 291 round_page(vm_page_dump_size)); 292 if (error) 293 goto fail; 294 295 /* Dump kernel page table pages */ 296 addr = dumpbuf; 297 for (va = KERNBASE; va < kernel_vm_end; va += PAGE_SIZE) { 298 pmap_dump_kextract(va, (pt2_entry_t *)addr); 299 addr += sizeof(pt2_entry_t); 300 if (addr == dumpbuf + sizeof(dumpbuf)) { 301 error = blk_write(di, dumpbuf, 0, sizeof(dumpbuf)); 302 if (error != 0) 303 goto fail; 304 addr = dumpbuf; 305 } 306 } 307 if (addr != dumpbuf) { 308 error = blk_write(di, dumpbuf, 0, addr - dumpbuf); 309 if (error != 0) 310 goto fail; 311 } 312 313 /* Dump memory chunks */ 314 for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) { 315 bits = vm_page_dump[i]; 316 while (bits) { 317 bit = ffs(bits) - 1; 318 pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + 319 bit) * PAGE_SIZE; 320 if (!count) { 321 prev_pa = pa; 322 count++; 323 } else { 324 if (pa == (prev_pa + count * PAGE_SIZE)) 325 count++; 326 else { 327 error = blk_write(di, NULL, prev_pa, 328 count * PAGE_SIZE); 329 if (error) 330 goto fail; 331 count = 1; 332 prev_pa = pa; 333 } 334 } 335 bits &= ~(1ul << bit); 336 } 337 } 338 if (count) { 339 error = blk_write(di, NULL, prev_pa, count * PAGE_SIZE); 340 if (error) 341 goto fail; 342 count = 0; 343 prev_pa = 0; 344 } 345 346 error = blk_flush(di); 347 if (error) 348 goto fail; 349 350 /* Dump trailer */ 351 error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh)); 352 if (error) 353 goto fail; 354 dumplo += sizeof(kdh); 355 356 /* Signal completion, signoff and exit stage left. */ 357 dump_write(di, NULL, 0, 0, 0); 358 printf("\nDump complete\n"); 359 return (0); 360 361fail: 362 if (error < 0) 363 error = -error; 364 365 if (error == ECANCELED) 366 printf("\nDump aborted\n"); 367 else if (error == ENOSPC) 368 printf("\nDump failed. Partition too small.\n"); 369 else 370 printf("\n** DUMP FAILED (ERROR %d) **\n", error); 371 return (error); 372} 373 374void 375dump_add_page(vm_paddr_t pa) 376{ 377 int idx, bit; 378 379 pa >>= PAGE_SHIFT; 380 idx = pa >> 5; /* 2^5 = 32 */ 381 bit = pa & 31; 382 atomic_set_int(&vm_page_dump[idx], 1ul << bit); 383} 384 385void 386dump_drop_page(vm_paddr_t pa) 387{ 388 int idx, bit; 389 390 pa >>= PAGE_SHIFT; 391 idx = pa >> 5; /* 2^5 = 32 */ 392 bit = pa & 31; 393 atomic_clear_int(&vm_page_dump[idx], 1ul << bit); 394} 395