1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2006 Peter Wemm 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_watchdog.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/conf.h> 37 #include <sys/cons.h> 38 #include <sys/kernel.h> 39 #include <sys/kerneldump.h> 40 #include <sys/msgbuf.h> 41 #include <sys/watchdog.h> 42 #include <vm/vm.h> 43 #include <vm/vm_param.h> 44 #include <vm/vm_page.h> 45 #include <vm/vm_phys.h> 46 #include <vm/pmap.h> 47 #include <machine/atomic.h> 48 #include <machine/elf.h> 49 #include <machine/md_var.h> 50 #include <machine/vmparam.h> 51 #include <machine/minidump.h> 52 53 CTASSERT(sizeof(struct kerneldumpheader) == 512); 54 55 #define MD_ALIGN(x) (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK) 56 #define DEV_ALIGN(x) roundup2((off_t)(x), DEV_BSIZE) 57 58 static struct kerneldumpheader kdh; 59 60 /* Handle chunked writes. */ 61 static size_t fragsz; 62 static void *dump_va; 63 static uint64_t counter, progress; 64 65 CTASSERT(sizeof(*vm_page_dump) == 4); 66 67 static int 68 is_dumpable(vm_paddr_t pa) 69 { 70 int i; 71 72 for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) { 73 if (pa >= dump_avail[i] && pa < dump_avail[i + 1]) 74 return (1); 75 } 76 return (0); 77 } 78 79 #define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8) 80 81 static int 82 blk_flush(struct dumperinfo *di) 83 { 84 int error; 85 86 if (fragsz == 0) 87 return (0); 88 89 error = dump_append(di, dump_va, 0, fragsz); 90 fragsz = 0; 91 return (error); 92 } 93 94 static int 95 blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz) 96 { 97 size_t len; 98 int error, i, c; 99 u_int maxdumpsz; 100 101 maxdumpsz = min(di->maxiosize, MAXDUMPPGS * PAGE_SIZE); 102 if (maxdumpsz == 0) /* seatbelt */ 103 maxdumpsz = PAGE_SIZE; 104 error = 0; 105 if ((sz % PAGE_SIZE) != 0) { 106 printf("size not page aligned\n"); 107 return (EINVAL); 108 } 109 if (ptr != NULL && pa != 0) { 110 printf("cant have both va and pa!\n"); 111 return (EINVAL); 112 } 113 if (pa != 0 && (((uintptr_t)ptr) % PAGE_SIZE) != 0) { 114 printf("address not page aligned\n"); 115 return (EINVAL); 116 } 117 if (ptr != NULL) { 118 /* If we're doing a virtual dump, flush any pre-existing pa pages */ 119 error = blk_flush(di); 120 if (error) 121 return (error); 122 } 123 while (sz) { 124 len = maxdumpsz - fragsz; 125 if (len > sz) 126 len = sz; 127 counter += len; 128 progress -= len; 129 if (counter >> 24) { 130 printf(" %lld", PG2MB(progress >> PAGE_SHIFT)); 131 counter &= (1<<24) - 1; 132 } 133 134 wdog_kern_pat(WD_LASTVAL); 135 136 if (ptr) { 137 error = dump_append(di, ptr, 0, len); 138 if (error) 139 return (error); 140 ptr += len; 141 sz -= len; 142 } else { 143 for (i = 0; i < len; i += PAGE_SIZE) 144 dump_va = pmap_kenter_temporary(pa + i, (i + fragsz) >> PAGE_SHIFT); 145 fragsz += len; 146 pa += len; 147 sz -= len; 148 if (fragsz == maxdumpsz) { 149 error = blk_flush(di); 150 if (error) 151 return (error); 152 } 153 } 154 155 /* Check for user abort. */ 156 c = cncheckc(); 157 if (c == 0x03) 158 return (ECANCELED); 159 if (c != -1) 160 printf(" (CTRL-C to abort) "); 161 } 162 163 return (0); 164 } 165 166 /* A fake page table page, to avoid having to handle both 4K and 2M pages */ 167 static pt_entry_t fakept[NPTEPG]; 168 169 #ifdef PMAP_PAE_COMP 170 #define minidumpsys minidumpsys_pae 171 #define IdlePTD IdlePTD_pae 172 #else 173 #define minidumpsys minidumpsys_nopae 174 #define IdlePTD IdlePTD_nopae 175 #endif 176 177 int 178 minidumpsys(struct dumperinfo *di) 179 { 180 uint64_t dumpsize; 181 uint32_t ptesize; 182 vm_offset_t va; 183 int error; 184 uint32_t bits; 185 uint64_t pa; 186 pd_entry_t *pd; 187 pt_entry_t *pt; 188 int i, j, k, bit; 189 struct minidumphdr mdhdr; 190 191 counter = 0; 192 /* Walk page table pages, set bits in vm_page_dump */ 193 ptesize = 0; 194 for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) { 195 /* 196 * We always write a page, even if it is zero. Each 197 * page written corresponds to 2MB of space 198 */ 199 ptesize += PAGE_SIZE; 200 pd = IdlePTD; /* always mapped! */ 201 j = va >> PDRSHIFT; 202 if ((pd[j] & (PG_PS | PG_V)) == (PG_PS | PG_V)) { 203 /* This is an entire 2M page. */ 204 pa = pd[j] & PG_PS_FRAME; 205 for (k = 0; k < NPTEPG; k++) { 206 if (is_dumpable(pa)) 207 dump_add_page(pa); 208 pa += PAGE_SIZE; 209 } 210 continue; 211 } 212 if ((pd[j] & PG_V) == PG_V) { 213 /* set bit for each valid page in this 2MB block */ 214 pt = pmap_kenter_temporary(pd[j] & PG_FRAME, 0); 215 for (k = 0; k < NPTEPG; k++) { 216 if ((pt[k] & PG_V) == PG_V) { 217 pa = pt[k] & PG_FRAME; 218 if (is_dumpable(pa)) 219 dump_add_page(pa); 220 } 221 } 222 } else { 223 /* nothing, we're going to dump a null page */ 224 } 225 } 226 227 /* Calculate dump size. */ 228 dumpsize = ptesize; 229 dumpsize += round_page(msgbufp->msg_size); 230 dumpsize += round_page(vm_page_dump_size); 231 for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) { 232 bits = vm_page_dump[i]; 233 while (bits) { 234 bit = bsfl(bits); 235 pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE; 236 /* Clear out undumpable pages now if needed */ 237 if (is_dumpable(pa)) { 238 dumpsize += PAGE_SIZE; 239 } else { 240 dump_drop_page(pa); 241 } 242 bits &= ~(1ul << bit); 243 } 244 } 245 dumpsize += PAGE_SIZE; 246 247 progress = dumpsize; 248 249 /* Initialize mdhdr */ 250 bzero(&mdhdr, sizeof(mdhdr)); 251 strcpy(mdhdr.magic, MINIDUMP_MAGIC); 252 mdhdr.version = MINIDUMP_VERSION; 253 mdhdr.msgbufsize = msgbufp->msg_size; 254 mdhdr.bitmapsize = vm_page_dump_size; 255 mdhdr.ptesize = ptesize; 256 mdhdr.kernbase = KERNBASE; 257 mdhdr.paemode = pae_mode; 258 259 dump_init_header(di, &kdh, KERNELDUMPMAGIC, KERNELDUMP_I386_VERSION, 260 dumpsize); 261 262 error = dump_start(di, &kdh); 263 if (error != 0) 264 goto fail; 265 266 printf("Physical memory: %ju MB\n", ptoa((uintmax_t)physmem) / 1048576); 267 printf("Dumping %llu MB:", (long long)dumpsize >> 20); 268 269 /* Dump my header */ 270 bzero(&fakept, sizeof(fakept)); 271 bcopy(&mdhdr, &fakept, sizeof(mdhdr)); 272 error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE); 273 if (error) 274 goto fail; 275 276 /* Dump msgbuf up front */ 277 error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size)); 278 if (error) 279 goto fail; 280 281 /* Dump bitmap */ 282 error = blk_write(di, (char *)vm_page_dump, 0, round_page(vm_page_dump_size)); 283 if (error) 284 goto fail; 285 286 /* Dump kernel page table pages */ 287 for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) { 288 /* We always write a page, even if it is zero */ 289 pd = IdlePTD; /* always mapped! */ 290 j = va >> PDRSHIFT; 291 if ((pd[j] & (PG_PS | PG_V)) == (PG_PS | PG_V)) { 292 /* This is a single 2M block. Generate a fake PTP */ 293 pa = pd[j] & PG_PS_FRAME; 294 for (k = 0; k < NPTEPG; k++) { 295 fakept[k] = (pa + (k * PAGE_SIZE)) | PG_V | PG_RW | PG_A | PG_M; 296 } 297 error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE); 298 if (error) 299 goto fail; 300 /* flush, in case we reuse fakept in the same block */ 301 error = blk_flush(di); 302 if (error) 303 goto fail; 304 continue; 305 } 306 if ((pd[j] & PG_V) == PG_V) { 307 pa = pd[j] & PG_FRAME; 308 error = blk_write(di, 0, pa, PAGE_SIZE); 309 if (error) 310 goto fail; 311 } else { 312 bzero(fakept, sizeof(fakept)); 313 error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE); 314 if (error) 315 goto fail; 316 /* flush, in case we reuse fakept in the same block */ 317 error = blk_flush(di); 318 if (error) 319 goto fail; 320 } 321 } 322 323 /* Dump memory chunks */ 324 for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) { 325 bits = vm_page_dump[i]; 326 while (bits) { 327 bit = bsfl(bits); 328 pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE; 329 error = blk_write(di, 0, pa, PAGE_SIZE); 330 if (error) 331 goto fail; 332 bits &= ~(1ul << bit); 333 } 334 } 335 336 error = blk_flush(di); 337 if (error) 338 goto fail; 339 340 error = dump_finish(di, &kdh); 341 if (error != 0) 342 goto fail; 343 344 printf("\nDump complete\n"); 345 return (0); 346 347 fail: 348 if (error < 0) 349 error = -error; 350 351 if (error == ECANCELED) 352 printf("\nDump aborted\n"); 353 else if (error == E2BIG || error == ENOSPC) { 354 printf("\nDump failed. Partition too small (about %lluMB were " 355 "needed this time).\n", (long long)dumpsize >> 20); 356 } else 357 printf("\n** DUMP FAILED (ERROR %d) **\n", error); 358 return (error); 359 } 360