sys/platform/pc64/x86_64/minidump_machdep.c

   1 /*-
   2  * Copyright (c) 2006 Peter Wemm
   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/minidump_machdep.c,v 1.10 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/device.h>
  34 #include <sys/globaldata.h>
  35 #include <sys/kernel.h>
  36 #include <sys/kerneldump.h>
  37 #include <sys/msgbuf.h>
  38 #include <vm/vm.h>
  39 #include <vm/vm_kern.h>
  40 #include <vm/pmap.h>
  41 #include <machine/atomic.h>
  42 #include <machine/elf.h>
  43 #include <machine/globaldata.h>
  44 #include <machine/md_var.h>
  45 #include <machine/vmparam.h>
  46 #include <machine/minidump.h>
  47
  48 CTASSERT(sizeof(struct kerneldumpheader) == 512);
  49
  50 /*
  51  * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
  52  * is to protect us from metadata and to protect metadata from us.
  53  */
  54 #define SIZEOF_METADATA         (64*1024)
  55
  56 #define MD_ALIGN(x)     (((off_t)(x) + PAGE_MASK) & ~PAGE_MASK)
  57 #define DEV_ALIGN(x)    (((off_t)(x) + (DEV_BSIZE-1)) & ~(DEV_BSIZE-1))
  58
  59 extern uint64_t KPDPphys;
  60
  61 uint64_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;
  69 static void *dump_va;
  70 static size_t counter, progress;
  71
  72 CTASSERT(sizeof(*vm_page_dump) == 8);
  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 = dev_ddump(di->priv, dump_va, 0, dumplo, fragsz);
  97         dumplo += fragsz;
  98         fragsz = 0;
  99         return (error);
 100 }
 101
 102 static int
 103 blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz)
 104 {
 105         size_t len;
 106         int error, i, c;
 107
 108         error = 0;
 109         if ((sz % PAGE_SIZE) != 0) {
 110                 kprintf("size not page aligned\n");
 111                 return (EINVAL);
 112         }
 113         if (ptr != NULL && pa != 0) {
 114                 kprintf("can't have both va and pa!\n");
 115                 return (EINVAL);
 116         }
 117         if (pa != 0 && (((uintptr_t)ptr) % PAGE_SIZE) != 0) {
 118                 kprintf("address not page aligned\n");
 119                 return (EINVAL);
 120         }
 121         if (ptr != NULL) {
 122                 /* If we're doing a virtual dump, flush any pre-existing pa pages */
 123                 error = blk_flush(di);
 124                 if (error)
 125                         return (error);
 126         }
 127         while (sz) {
 128                 len = (MAXDUMPPGS * PAGE_SIZE) - fragsz;
 129                 if (len > sz)
 130                         len = sz;
 131                 counter += len;
 132                 progress -= len;
 133                 if (counter >> 24) {
 134                         kprintf(" %ld", PG2MB(progress >> PAGE_SHIFT));
 135                         counter &= (1<<24) - 1;
 136                 }
 137                 if (ptr) {
 138                         error = dev_ddump(di->priv, ptr, 0, dumplo, len);
 139                         if (error)
 140                                 return (error);
 141                         dumplo += len;
 142                         ptr += len;
 143                         sz -= len;
 144                 } else {
 145                         for (i = 0; i < len; i += PAGE_SIZE)
 146                                 dump_va = pmap_kenter_temporary(pa + i, (i + fragsz) >> PAGE_SHIFT);
 147                         fragsz += len;
 148                         pa += len;
 149                         sz -= len;
 150                         if (fragsz == (MAXDUMPPGS * PAGE_SIZE)) {
 151                                 error = blk_flush(di);
 152                                 if (error)
 153                                         return (error);
 154                         }
 155                 }
 156
 157                 /* Check for user abort. */
 158                 c = cncheckc();
 159                 if (c == 0x03)
 160                         return (ECANCELED);
 161                 if (c != -1)
 162                         kprintf(" (CTRL-C to abort) ");
 163         }
 164
 165         return (0);
 166 }
 167
 168 /* A fake page table page, to avoid having to handle both 4K and 2M pages */
 169 static pt_entry_t fakept[NPTEPG];
 170
 171 void
 172 minidumpsys(struct dumperinfo *di)
 173 {
 174         uint64_t dumpsize;
 175         uint32_t ptesize;
 176         vm_offset_t va;
 177         vm_offset_t kern_end;
 178         int error;
 179         uint64_t bits;
 180         uint64_t *pdp, *pd, *pt, pa;
 181         int i, j, k, bit;
 182         struct minidumphdr mdhdr;
 183         struct mdglobaldata *md;
 184
 185         counter = 0;
 186         /*
 187          * Walk page table pages, set bits in vm_page_dump.
 188          *
 189          * NOTE: kernel_vm_end can actually be below KERNBASE.
 190          *       Just use KvaEnd.  Also note that loops which go
 191          *       all the way to the end of the address space might
 192          *       overflow the loop variable.
 193          */
 194         ptesize = 0;
 195
 196         md = (struct mdglobaldata *)globaldata_find(0);
 197
 198         kern_end = KvaEnd;
 199         if (kern_end < (vm_offset_t)&(md[ncpus]))
 200                 kern_end = (vm_offset_t)&(md[ncpus]);
 201
 202         pdp = (uint64_t *)PHYS_TO_DMAP(KPDPphys);
 203         for (va = VM_MIN_KERNEL_ADDRESS; va < kern_end; va += NBPDR) {
 204                 /*
 205                  * The loop probably overflows a 64-bit int due to NBPDR.
 206                  */
 207                 if (va < VM_MIN_KERNEL_ADDRESS)
 208                         break;
 209
 210                 /*
 211                  * We always write a page, even if it is zero. Each
 212                  * page written corresponds to 2MB of space
 213                  */
 214                 i = (va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1);
 215                 ptesize += PAGE_SIZE;
 216                 if ((pdp[i] & PG_V) == 0)
 217                         continue;
 218                 pd = (uint64_t *)PHYS_TO_DMAP(pdp[i] & PG_FRAME);
 219                 j = ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
 220                 if ((pd[j] & (PG_PS | PG_V)) == (PG_PS | PG_V))  {
 221                         /* This is an entire 2M page. */
 222                         pa = pd[j] & PG_PS_FRAME;
 223                         for (k = 0; k < NPTEPG; k++) {
 224                                 if (is_dumpable(pa))
 225                                         dump_add_page(pa);
 226                                 pa += PAGE_SIZE;
 227                         }
 228                         continue;
 229                 }
 230                 if ((pd[j] & PG_V) == PG_V) {
 231                         /* set bit for each valid page in this 2MB block */
 232                         pt = (uint64_t *)PHYS_TO_DMAP(pd[j] & PG_FRAME);
 233                         for (k = 0; k < NPTEPG; k++) {
 234                                 if ((pt[k] & PG_V) == PG_V) {
 235                                         pa = pt[k] & PG_FRAME;
 236                                         if (is_dumpable(pa))
 237                                                 dump_add_page(pa);
 238                                 }
 239                         }
 240                 } else {
 241                         /* nothing, we're going to dump a null page */
 242                 }
 243         }
 244
 245         /* Calculate dump size. */
 246         dumpsize = ptesize;
 247         dumpsize += round_page(msgbufp->msg_size);
 248         dumpsize += round_page(vm_page_dump_size);
 249         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
 250                 bits = vm_page_dump[i];
 251                 while (bits) {
 252                         bit = bsfq(bits);
 253                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE;
 254                         /* Clear out undumpable pages now if needed */
 255                         if (is_dumpable(pa)) {
 256                                 dumpsize += PAGE_SIZE;
 257                         } else {
 258                                 dump_drop_page(pa);
 259                         }
 260                         bits &= ~(1ul << bit);
 261                 }
 262         }
 263         dumpsize += PAGE_SIZE;
 264
 265         /* Determine dump offset on device. */
 266         if (di->mediasize < SIZEOF_METADATA + dumpsize + sizeof(kdh) * 2) {
 267                 error = ENOSPC;
 268                 goto fail;
 269         }
 270         dumplo = di->mediaoffset + di->mediasize - dumpsize;
 271         dumplo -= sizeof(kdh) * 2;
 272         progress = dumpsize;
 273
 274         /* Initialize mdhdr */
 275         bzero(&mdhdr, sizeof(mdhdr));
 276         strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 277         mdhdr.version = MINIDUMP_VERSION;
 278         mdhdr.msgbufsize = msgbufp->msg_size;
 279         mdhdr.bitmapsize = vm_page_dump_size;
 280         mdhdr.ptesize = ptesize;
 281         mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
 282         mdhdr.dmapbase = DMAP_MIN_ADDRESS;
 283         mdhdr.dmapend = DMAP_MAX_ADDRESS;
 284
 285         mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION,
 286             dumpsize, di->blocksize);
 287
 288         kprintf("Physical memory: %jd MB\n", (intmax_t)ptoa(physmem) / 1048576);
 289         kprintf("Dumping %jd MB:", (intmax_t)dumpsize >> 20);
 290
 291         /* Dump leader */
 292         error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh));
 293         if (error)
 294                 goto fail;
 295         dumplo += sizeof(kdh);
 296
 297         /* Dump my header */
 298         bzero(&fakept, sizeof(fakept));
 299         bcopy(&mdhdr, &fakept, sizeof(mdhdr));
 300         error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
 301         if (error)
 302                 goto fail;
 303
 304         /* Dump msgbuf up front */
 305         error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
 306         if (error)
 307                 goto fail;
 308
 309         /* Dump bitmap */
 310         error = blk_write(di, (char *)vm_page_dump, 0, round_page(vm_page_dump_size));
 311         if (error)
 312                 goto fail;
 313
 314         /* Dump kernel page table pages */
 315         pdp = (uint64_t *)PHYS_TO_DMAP(KPDPphys);
 316         for (va = VM_MIN_KERNEL_ADDRESS; va < kern_end; va += NBPDR) {
 317                 /*
 318                  * The loop probably overflows a 64-bit int due to NBPDR.
 319                  */
 320                 if (va < VM_MIN_KERNEL_ADDRESS)
 321                         break;
 322
 323                 /*
 324                  * We always write a page, even if it is zero
 325                  */
 326                 i = (va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1);
 327                 if ((pdp[i] & PG_V) == 0) {
 328                         bzero(fakept, sizeof(fakept));
 329                         error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
 330                         if (error)
 331                                 goto fail;
 332                         /* flush, in case we reuse fakept in the same block */
 333                         error = blk_flush(di);
 334                         if (error)
 335                                 goto fail;
 336                         continue;
 337                 }
 338                 pd = (uint64_t *)PHYS_TO_DMAP(pdp[i] & PG_FRAME);
 339                 j = ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
 340                 if ((pd[j] & (PG_PS | PG_V)) == (PG_PS | PG_V))  {
 341                         /* This is a single 2M block. Generate a fake PTP */
 342                         pa = pd[j] & PG_PS_FRAME;
 343                         for (k = 0; k < NPTEPG; k++) {
 344                                 fakept[k] = (pa + (k * PAGE_SIZE)) | PG_V | PG_RW | PG_A | PG_M;
 345                         }
 346                         error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
 347                         if (error)
 348                                 goto fail;
 349                         /* flush, in case we reuse fakept in the same block */
 350                         error = blk_flush(di);
 351                         if (error)
 352                                 goto fail;
 353                         continue;
 354                 }
 355                 if ((pd[j] & PG_V) == PG_V) {
 356                         pt = (uint64_t *)PHYS_TO_DMAP(pd[j] & PG_FRAME);
 357                         error = blk_write(di, (char *)pt, 0, PAGE_SIZE);
 358                         if (error)
 359                                 goto fail;
 360                 } else {
 361                         bzero(fakept, sizeof(fakept));
 362                         error = blk_write(di, (char *)&fakept, 0, PAGE_SIZE);
 363                         if (error)
 364                                 goto fail;
 365                         /* flush, in case we reuse fakept in the same block */
 366                         error = blk_flush(di);
 367                         if (error)
 368                                 goto fail;
 369                 }
 370         }
 371
 372         /* Dump memory chunks */
 373         /* XXX cluster it up and use blk_dump() */
 374         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
 375                 bits = vm_page_dump[i];
 376                 while (bits) {
 377                         bit = bsfq(bits);
 378                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE;
 379                         error = blk_write(di, 0, pa, PAGE_SIZE);
 380                         if (error)
 381                                 goto fail;
 382                         bits &= ~(1ul << bit);
 383                 }
 384         }
 385
 386         error = blk_flush(di);
 387         if (error)
 388                 goto fail;
 389
 390         /* Dump trailer */
 391         error = dev_ddump(di->priv, &kdh, 0, dumplo, sizeof(kdh));
 392         if (error)
 393                 goto fail;
 394         dumplo += sizeof(kdh);
 395
 396         /* Signal completion, signoff and exit stage left. */
 397         dev_ddump(di->priv, NULL, 0, 0, 0);
 398         kprintf("\nDump complete\n");
 399         return;
 400
 401  fail:
 402         if (error < 0)
 403                 error = -error;
 404
 405         if (error == ECANCELED)
 406                 kprintf("\nDump aborted\n");
 407         else if (error == ENOSPC)
 408                 kprintf("\nDump failed. Partition too small.\n");
 409         else
 410                 kprintf("\n** DUMP FAILED (ERROR %d) **\n", error);
 411 }
 412
 413 void
 414 dump_add_page(vm_paddr_t pa)
 415 {
 416         int idx, bit;
 417
 418         pa >>= PAGE_SHIFT;
 419         idx = pa >> 6;          /* 2^6 = 64 */
 420         bit = pa & 63;
 421         atomic_set_long(&vm_page_dump[idx], 1ul << bit);
 422 }
 423
 424 void
 425 dump_drop_page(vm_paddr_t pa)
 426 {
 427         int idx, bit;
 428
 429         pa >>= PAGE_SHIFT;
 430         idx = pa >> 6;          /* 2^6 = 64 */
 431         bit = pa & 63;
 432         atomic_clear_long(&vm_page_dump[idx], 1ul << bit);
 433 }