sys/arm/arm/minidump_machdep.c

   1 /*-
   2  * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
   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  * from: FreeBSD: src/sys/i386/i386/minidump_machdep.c,v 1.6 2008/08/17 23:27:27
  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 #ifdef SW_WATCHDOG
  42 #include <sys/watchdog.h>
  43 #endif
  44 #include <vm/vm.h>
  45 #include <vm/pmap.h>
  46 #include <machine/atomic.h>
  47 #include <machine/elf.h>
  48 #include <machine/md_var.h>
  49 #include <machine/vmparam.h>
  50 #include <machine/minidump.h>
  51 #include <machine/cpufunc.h>
  52
  53 CTASSERT(sizeof(struct kerneldumpheader) == 512);
  54
  55 /*
  56  * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
  57  * is to protect us from metadata and to protect metadata from us.
  58  */
  59 #define SIZEOF_METADATA         (64*1024)
  60
  61 uint32_t *vm_page_dump;
  62 int vm_page_dump_size;
  63
  64 static struct kerneldumpheader kdh;
  65 static off_t dumplo;
  66
  67 /* Handle chunked writes. */
  68 static size_t fragsz, offset;
  69 static void *dump_va;
  70 static uint64_t counter, progress;
  71
  72 CTASSERT(sizeof(*vm_page_dump) == 4);
  73
  74 static int
  75 is_dumpable(vm_paddr_t pa)
  76 {
  77         int i;
  78
  79         for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
  80                 if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
  81                         return (1);
  82         }
  83         return (0);
  84 }
  85
  86 #define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8)
  87
  88 static int
  89 blk_flush(struct dumperinfo *di)
  90 {
  91         int error;
  92
  93         if (fragsz == 0)
  94                 return (0);
  95
  96         error = dump_write(di, (char*)dump_va + offset, 0, dumplo, fragsz - offset);
  97         dumplo += (fragsz - offset);
  98         fragsz = 0;
  99         offset = 0;
 100         return (error);
 101 }
 102
 103 static int
 104 blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz)
 105 {
 106         size_t len;
 107         int error, i, c;
 108         u_int maxdumpsz;
 109
 110         maxdumpsz = di->maxiosize;
 111
 112         if (maxdumpsz == 0)     /* seatbelt */
 113                 maxdumpsz = PAGE_SIZE;
 114
 115         error = 0;
 116
 117         if (ptr != NULL && pa != 0) {
 118                 printf("cant have both va and pa!\n");
 119                 return (EINVAL);
 120         }
 121
 122         if (ptr != NULL) {
 123                 /* If we're doing a virtual dump, flush any pre-existing pa pages */
 124                 error = blk_flush(di);
 125                 if (error)
 126                         return (error);
 127         }
 128
 129         while (sz) {
 130                 if (fragsz == 0) {
 131                         offset = pa & PAGE_MASK;
 132                         fragsz += offset;
 133                 }
 134                 len = maxdumpsz - fragsz;
 135                 if (len > sz)
 136                         len = sz;
 137                 counter += len;
 138                 progress -= len;
 139
 140                 if (counter >> 22) {
 141                         printf(" %lld", PG2MB(progress >> PAGE_SHIFT));
 142                         counter &= (1<<22) - 1;
 143                 }
 144
 145 #ifdef SW_WATCHDOG
 146                 wdog_kern_pat(WD_LASTVAL);
 147 #endif
 148                 if (ptr) {
 149                         error = dump_write(di, ptr, 0, dumplo, len);
 150                         if (error)
 151                                 return (error);
 152                         dumplo += len;
 153                         ptr += len;
 154                         sz -= len;
 155                 } else {
 156                         for (i = 0; i < len; i += PAGE_SIZE)
 157                                 dump_va = pmap_kenter_temporary(pa + i,
 158                                     (i + fragsz) >> PAGE_SHIFT);
 159                         fragsz += len;
 160                         pa += len;
 161                         sz -= len;
 162                         if (fragsz == maxdumpsz) {
 163                                 error = blk_flush(di);
 164                                 if (error)
 165                                         return (error);
 166                         }
 167                 }
 168
 169                 /* Check for user abort. */
 170                 c = cncheckc();
 171                 if (c == 0x03)
 172                         return (ECANCELED);
 173                 if (c != -1)
 174                         printf(" (CTRL-C to abort) ");
 175         }
 176
 177         return (0);
 178 }
 179
 180 static int
 181 blk_write_cont(struct dumperinfo *di, vm_paddr_t pa, size_t sz)
 182 {
 183         int error;
 184
 185         error = blk_write(di, 0, pa, sz);
 186         if (error)
 187                 return (error);
 188
 189         error = blk_flush(di);
 190         if (error)
 191                 return (error);
 192
 193         return (0);
 194 }
 195
 196 /* A fake page table page, to avoid having to handle both 4K and 2M pages */
 197 static pt_entry_t fakept[NPTEPG];
 198
 199 void
 200 minidumpsys(struct dumperinfo *di)
 201 {
 202         struct minidumphdr mdhdr;
 203         uint64_t dumpsize;
 204         uint32_t ptesize;
 205         uint32_t bits;
 206         uint32_t pa, prev_pa = 0, count = 0;
 207         vm_offset_t va;
 208         pd_entry_t *pdp;
 209         pt_entry_t *pt, *ptp;
 210         int i, k, bit, error;
 211         char *addr;
 212
 213         /*
 214          * Flush caches.  Note that in the SMP case this operates only on the
 215          * current CPU's L1 cache.  Before we reach this point, code in either
 216          * the system shutdown or kernel debugger has called stop_cpus() to stop
 217          * all cores other than this one.  Part of the ARM handling of
 218          * stop_cpus() is to call wbinv_all() on that core's local L1 cache.  So
 219          * by time we get to here, all that remains is to flush the L1 for the
 220          * current CPU, then the L2.
 221          */
 222         cpu_idcache_wbinv_all();
 223         cpu_l2cache_wbinv_all();
 224
 225         counter = 0;
 226         /* Walk page table pages, set bits in vm_page_dump */
 227         ptesize = 0;
 228         for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) {
 229                 /*
 230                  * We always write a page, even if it is zero. Each
 231                  * page written corresponds to 2MB of space
 232                  */
 233                 ptesize += L2_TABLE_SIZE_REAL;
 234                 pmap_get_pde_pte(pmap_kernel(), va, &pdp, &ptp);
 235                 if (pmap_pde_v(pdp) && pmap_pde_section(pdp)) {
 236                         /* This is a section mapping 1M page. */
 237                         pa = (*pdp & L1_S_ADDR_MASK) | (va & ~L1_S_ADDR_MASK);
 238                         for (k = 0; k < (L1_S_SIZE / PAGE_SIZE); k++) {
 239                                 if (is_dumpable(pa))
 240                                         dump_add_page(pa);
 241                                 pa += PAGE_SIZE;
 242                         }
 243                         continue;
 244                 }
 245                 if (pmap_pde_v(pdp) && pmap_pde_page(pdp)) {
 246                         /* Set bit for each valid page in this 1MB block */
 247                         addr = pmap_kenter_temporary(*pdp & L1_C_ADDR_MASK, 0);
 248                         pt = (pt_entry_t*)(addr +
 249                             (((uint32_t)*pdp  & L1_C_ADDR_MASK) & PAGE_MASK));
 250                         for (k = 0; k < 256; k++) {
 251                                 if ((pt[k] & L2_TYPE_MASK) == L2_TYPE_L) {
 252                                         pa = (pt[k] & L2_L_FRAME) |
 253                                             (va & L2_L_OFFSET);
 254                                         for (i = 0; i < 16; i++) {
 255                                                 if (is_dumpable(pa))
 256                                                         dump_add_page(pa);
 257                                                 k++;
 258                                                 pa += PAGE_SIZE;
 259                                         }
 260                                 } else if ((pt[k] & L2_TYPE_MASK) == L2_TYPE_S) {
 261                                         pa = (pt[k] & L2_S_FRAME) |
 262                                             (va & L2_S_OFFSET);
 263                                         if (is_dumpable(pa))
 264                                                 dump_add_page(pa);
 265                                 }
 266                         }
 267                 } else {
 268                         /* Nothing, we're going to dump a null page */
 269                 }
 270         }
 271
 272         /* Calculate dump size. */
 273         dumpsize = ptesize;
 274         dumpsize += round_page(msgbufp->msg_size);
 275         dumpsize += round_page(vm_page_dump_size);
 276
 277         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
 278                 bits = vm_page_dump[i];
 279                 while (bits) {
 280                         bit = ffs(bits) - 1;
 281                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
 282                             bit) * PAGE_SIZE;
 283                         /* Clear out undumpable pages now if needed */
 284                         if (is_dumpable(pa))
 285                                 dumpsize += PAGE_SIZE;
 286                         else
 287                                 dump_drop_page(pa);
 288                         bits &= ~(1ul << bit);
 289                 }
 290         }
 291
 292         dumpsize += PAGE_SIZE;
 293
 294         /* Determine dump offset on device. */
 295         if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
 296                 error = ENOSPC;
 297                 goto fail;
 298         }
 299
 300         dumplo = di->mediaoffset + di->mediasize - dumpsize;
 301         dumplo -= sizeof(kdh) * 2;
 302         progress = dumpsize;
 303
 304         /* Initialize mdhdr */
 305         bzero(&mdhdr, sizeof(mdhdr));
 306         strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 307         mdhdr.version = MINIDUMP_VERSION;
 308         mdhdr.msgbufsize = msgbufp->msg_size;
 309         mdhdr.bitmapsize = vm_page_dump_size;
 310         mdhdr.ptesize = ptesize;
 311         mdhdr.kernbase = KERNBASE;
 312
 313         mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_ARM_VERSION, dumpsize,
 314             di->blocksize);
 315
 316         printf("Physical memory: %u MB\n", ptoa((uintmax_t)physmem) / 1048576);
 317         printf("Dumping %llu MB:", (long long)dumpsize >> 20);
 318
 319         /* Dump leader */
 320         error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
 321         if (error)
 322                 goto fail;
 323         dumplo += sizeof(kdh);
 324
 325         /* Dump my header */
 326         bzero(&fakept, sizeof(fakept));
 327         bcopy(&mdhdr, &fakept, sizeof(mdhdr));
 328         error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
 329         if (error)
 330                 goto fail;
 331
 332         /* Dump msgbuf up front */
 333         error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
 334         if (error)
 335                 goto fail;
 336
 337         /* Dump bitmap */
 338         error = blk_write(di, (char *)vm_page_dump, 0,
 339             round_page(vm_page_dump_size));
 340         if (error)
 341                 goto fail;
 342
 343         /* Dump kernel page table pages */
 344         for (va = KERNBASE; va < kernel_vm_end; va += NBPDR) {
 345                 /* We always write a page, even if it is zero */
 346                 pmap_get_pde_pte(pmap_kernel(), va, &pdp, &ptp);
 347
 348                 if (pmap_pde_v(pdp) && pmap_pde_section(pdp))  {
 349                         if (count) {
 350                                 error = blk_write_cont(di, prev_pa,
 351                                     count * L2_TABLE_SIZE_REAL);
 352                                 if (error)
 353                                         goto fail;
 354                                 count = 0;
 355                                 prev_pa = 0;
 356                         }
 357                         /* This is a single 2M block. Generate a fake PTP */
 358                         pa = (*pdp & L1_S_ADDR_MASK) | (va & ~L1_S_ADDR_MASK);
 359                         for (k = 0; k < (L1_S_SIZE / PAGE_SIZE); k++) {
 360                                 fakept[k] = L2_S_PROTO | (pa + (k * PAGE_SIZE)) |
 361                                     L2_S_PROT(PTE_KERNEL,
 362                                     VM_PROT_READ | VM_PROT_WRITE);
 363                         }
 364                         error = blk_write(di, (char *)&fakept, 0,
 365                             L2_TABLE_SIZE_REAL);
 366                         if (error)
 367                                 goto fail;
 368                         /* Flush, in case we reuse fakept in the same block */
 369                         error = blk_flush(di);
 370                         if (error)
 371                                 goto fail;
 372                         continue;
 373                 }
 374                 if (pmap_pde_v(pdp) && pmap_pde_page(pdp)) {
 375                         pa = *pdp & L1_C_ADDR_MASK;
 376                         if (!count) {
 377                                 prev_pa = pa;
 378                                 count++;
 379                         }
 380                         else {
 381                                 if (pa == (prev_pa + count * L2_TABLE_SIZE_REAL))
 382                                         count++;
 383                                 else {
 384                                         error = blk_write_cont(di, prev_pa,
 385                                             count * L2_TABLE_SIZE_REAL);
 386                                         if (error)
 387                                                 goto fail;
 388                                         count = 1;
 389                                         prev_pa = pa;
 390                                 }
 391                         }
 392                 } else {
 393                         if (count) {
 394                                 error = blk_write_cont(di, prev_pa,
 395                                     count * L2_TABLE_SIZE_REAL);
 396                                 if (error)
 397                                         goto fail;
 398                                 count = 0;
 399                                 prev_pa = 0;
 400                         }
 401                         bzero(fakept, sizeof(fakept));
 402                         error = blk_write(di, (char *)&fakept, 0,
 403                             L2_TABLE_SIZE_REAL);
 404                         if (error)
 405                                 goto fail;
 406                         /* Flush, in case we reuse fakept in the same block */
 407                         error = blk_flush(di);
 408                         if (error)
 409                                 goto fail;
 410                 }
 411         }
 412
 413         if (count) {
 414                 error = blk_write_cont(di, prev_pa, count * L2_TABLE_SIZE_REAL);
 415                 if (error)
 416                         goto fail;
 417                 count = 0;
 418                 prev_pa = 0;
 419         }
 420
 421         /* Dump memory chunks */
 422         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
 423                 bits = vm_page_dump[i];
 424                 while (bits) {
 425                         bit = ffs(bits) - 1;
 426                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) +
 427                             bit) * PAGE_SIZE;
 428                         if (!count) {
 429                                 prev_pa = pa;
 430                                 count++;
 431                         } else {
 432                                 if (pa == (prev_pa + count * PAGE_SIZE))
 433                                         count++;
 434                                 else {
 435                                         error = blk_write_cont(di, prev_pa,
 436                                             count * PAGE_SIZE);
 437                                         if (error)
 438                                                 goto fail;
 439                                         count = 1;
 440                                         prev_pa = pa;
 441                                 }
 442                         }
 443                         bits &= ~(1ul << bit);
 444                 }
 445         }
 446         if (count) {
 447                 error = blk_write_cont(di, prev_pa, count * PAGE_SIZE);
 448                 if (error)
 449                         goto fail;
 450                 count = 0;
 451                 prev_pa = 0;
 452         }
 453
 454         /* Dump trailer */
 455         error = dump_write(di, &kdh, 0, dumplo, sizeof(kdh));
 456         if (error)
 457                 goto fail;
 458         dumplo += sizeof(kdh);
 459
 460         /* Signal completion, signoff and exit stage left. */
 461         dump_write(di, NULL, 0, 0, 0);
 462         printf("\nDump complete\n");
 463         return;
 464
 465 fail:
 466         if (error < 0)
 467                 error = -error;
 468
 469         if (error == ECANCELED)
 470                 printf("\nDump aborted\n");
 471         else if (error == ENOSPC)
 472                 printf("\nDump failed. Partition too small.\n");
 473         else
 474                 printf("\n** DUMP FAILED (ERROR %d) **\n", error);
 475 }
 476
 477 void
 478 dump_add_page(vm_paddr_t pa)
 479 {
 480         int idx, bit;
 481
 482         pa >>= PAGE_SHIFT;
 483         idx = pa >> 5;          /* 2^5 = 32 */
 484         bit = pa & 31;
 485         atomic_set_int(&vm_page_dump[idx], 1ul << bit);
 486 }
 487
 488 void
 489 dump_drop_page(vm_paddr_t pa)
 490 {
 491         int idx, bit;
 492
 493         pa >>= PAGE_SHIFT;
 494         idx = pa >> 5;          /* 2^5 = 32 */
 495         bit = pa & 31;
 496         atomic_clear_int(&vm_page_dump[idx], 1ul << bit);
 497 }