The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/minidump_machdep.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    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 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD: releng/11.1/sys/amd64/amd64/minidump_machdep.c 306365 2016-09-27 10:26:39Z kib $");
   29 
   30 #include "opt_pmap.h"
   31 #include "opt_watchdog.h"
   32 
   33 #include <sys/param.h>
   34 #include <sys/systm.h>
   35 #include <sys/conf.h>
   36 #include <sys/cons.h>
   37 #include <sys/kernel.h>
   38 #include <sys/kerneldump.h>
   39 #include <sys/msgbuf.h>
   40 #include <sys/watchdog.h>
   41 #include <vm/vm.h>
   42 #include <vm/vm_param.h>
   43 #include <vm/vm_page.h>
   44 #include <vm/vm_phys.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/minidump.h>
   50 
   51 CTASSERT(sizeof(struct kerneldumpheader) == 512);
   52 
   53 /*
   54  * Don't touch the first SIZEOF_METADATA bytes on the dump device. This
   55  * is to protect us from metadata and to protect metadata from us.
   56  */
   57 #define SIZEOF_METADATA         (64*1024)
   58 
   59 uint64_t *vm_page_dump;
   60 int vm_page_dump_size;
   61 
   62 static struct kerneldumpheader kdh;
   63 static off_t dumplo;
   64 
   65 /* Handle chunked writes. */
   66 static size_t fragsz;
   67 static void *dump_va;
   68 static size_t counter, progress, dumpsize;
   69 
   70 CTASSERT(sizeof(*vm_page_dump) == 8);
   71 
   72 static int
   73 is_dumpable(vm_paddr_t pa)
   74 {
   75         vm_page_t m;
   76         int i;
   77 
   78         if ((m = vm_phys_paddr_to_vm_page(pa)) != NULL)
   79                 return ((m->flags & PG_NODUMP) == 0);
   80         for (i = 0; dump_avail[i] != 0 || dump_avail[i + 1] != 0; i += 2) {
   81                 if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
   82                         return (1);
   83         }
   84         return (0);
   85 }
   86 
   87 #define PG2MB(pgs) (((pgs) + (1 << 8) - 1) >> 8)
   88 
   89 static int
   90 blk_flush(struct dumperinfo *di)
   91 {
   92         int error;
   93 
   94         if (fragsz == 0)
   95                 return (0);
   96 
   97         error = dump_write(di, dump_va, 0, dumplo, fragsz);
   98         dumplo += fragsz;
   99         fragsz = 0;
  100         return (error);
  101 }
  102 
  103 static struct {
  104         int min_per;
  105         int max_per;
  106         int visited;
  107 } progress_track[10] = {
  108         {  0,  10, 0},
  109         { 10,  20, 0},
  110         { 20,  30, 0},
  111         { 30,  40, 0},
  112         { 40,  50, 0},
  113         { 50,  60, 0},
  114         { 60,  70, 0},
  115         { 70,  80, 0},
  116         { 80,  90, 0},
  117         { 90, 100, 0}
  118 };
  119 
  120 static void
  121 report_progress(size_t progress, size_t dumpsize)
  122 {
  123         int sofar, i;
  124 
  125         sofar = 100 - ((progress * 100) / dumpsize);
  126         for (i = 0; i < nitems(progress_track); i++) {
  127                 if (sofar < progress_track[i].min_per ||
  128                     sofar > progress_track[i].max_per)
  129                         continue;
  130                 if (progress_track[i].visited)
  131                         return;
  132                 progress_track[i].visited = 1;
  133                 printf("..%d%%", sofar);
  134                 return;
  135         }
  136 }
  137 
  138 static int
  139 blk_write(struct dumperinfo *di, char *ptr, vm_paddr_t pa, size_t sz)
  140 {
  141         size_t len;
  142         int error, i, c;
  143         u_int maxdumpsz;
  144 
  145         maxdumpsz = min(di->maxiosize, MAXDUMPPGS * PAGE_SIZE);
  146         if (maxdumpsz == 0)     /* seatbelt */
  147                 maxdumpsz = PAGE_SIZE;
  148         error = 0;
  149         if ((sz % PAGE_SIZE) != 0) {
  150                 printf("size not page aligned\n");
  151                 return (EINVAL);
  152         }
  153         if (ptr != NULL && pa != 0) {
  154                 printf("cant have both va and pa!\n");
  155                 return (EINVAL);
  156         }
  157         if ((((uintptr_t)pa) % PAGE_SIZE) != 0) {
  158                 printf("address not page aligned %p\n", ptr);
  159                 return (EINVAL);
  160         }
  161         if (ptr != NULL) {
  162                 /* If we're doing a virtual dump, flush any pre-existing pa pages */
  163                 error = blk_flush(di);
  164                 if (error)
  165                         return (error);
  166         }
  167         while (sz) {
  168                 len = maxdumpsz - fragsz;
  169                 if (len > sz)
  170                         len = sz;
  171                 counter += len;
  172                 progress -= len;
  173                 if (counter >> 24) {
  174                         report_progress(progress, dumpsize);
  175                         counter &= (1<<24) - 1;
  176                 }
  177 
  178                 wdog_kern_pat(WD_LASTVAL);
  179 
  180                 if (ptr) {
  181                         error = dump_write(di, ptr, 0, dumplo, len);
  182                         if (error)
  183                                 return (error);
  184                         dumplo += len;
  185                         ptr += len;
  186                         sz -= len;
  187                 } else {
  188                         for (i = 0; i < len; i += PAGE_SIZE)
  189                                 dump_va = pmap_kenter_temporary(pa + i, (i + fragsz) >> PAGE_SHIFT);
  190                         fragsz += len;
  191                         pa += len;
  192                         sz -= len;
  193                         if (fragsz == maxdumpsz) {
  194                                 error = blk_flush(di);
  195                                 if (error)
  196                                         return (error);
  197                         }
  198                 }
  199 
  200                 /* Check for user abort. */
  201                 c = cncheckc();
  202                 if (c == 0x03)
  203                         return (ECANCELED);
  204                 if (c != -1)
  205                         printf(" (CTRL-C to abort) ");
  206         }
  207 
  208         return (0);
  209 }
  210 
  211 /* A fake page table page, to avoid having to handle both 4K and 2M pages */
  212 static pd_entry_t fakepd[NPDEPG];
  213 
  214 int
  215 minidumpsys(struct dumperinfo *di)
  216 {
  217         uint32_t pmapsize;
  218         vm_offset_t va;
  219         int error;
  220         uint64_t bits;
  221         uint64_t *pml4, *pdp, *pd, *pt, pa;
  222         size_t size;
  223         int i, ii, j, k, n, bit;
  224         int retry_count;
  225         struct minidumphdr mdhdr;
  226 
  227         retry_count = 0;
  228  retry:
  229         retry_count++;
  230         counter = 0;
  231         for (i = 0; i < nitems(progress_track); i++)
  232                 progress_track[i].visited = 0;
  233         /* Walk page table pages, set bits in vm_page_dump */
  234         pmapsize = 0;
  235         for (va = VM_MIN_KERNEL_ADDRESS; va < MAX(KERNBASE + nkpt * NBPDR,
  236             kernel_vm_end); ) {
  237                 /*
  238                  * We always write a page, even if it is zero. Each
  239                  * page written corresponds to 1GB of space
  240                  */
  241                 pmapsize += PAGE_SIZE;
  242                 ii = pmap_pml4e_index(va);
  243                 pml4 = (uint64_t *)PHYS_TO_DMAP(KPML4phys) + ii;
  244                 pdp = (uint64_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
  245                 i = pmap_pdpe_index(va);
  246                 if ((pdp[i] & PG_V) == 0) {
  247                         va += NBPDP;
  248                         continue;
  249                 }
  250 
  251                 /*
  252                  * 1GB page is represented as 512 2MB pages in a dump.
  253                  */
  254                 if ((pdp[i] & PG_PS) != 0) {
  255                         va += NBPDP;
  256                         pa = pdp[i] & PG_PS_FRAME;
  257                         for (n = 0; n < NPDEPG * NPTEPG; n++) {
  258                                 if (is_dumpable(pa))
  259                                         dump_add_page(pa);
  260                                 pa += PAGE_SIZE;
  261                         }
  262                         continue;
  263                 }
  264 
  265                 pd = (uint64_t *)PHYS_TO_DMAP(pdp[i] & PG_FRAME);
  266                 for (n = 0; n < NPDEPG; n++, va += NBPDR) {
  267                         j = pmap_pde_index(va);
  268 
  269                         if ((pd[j] & PG_V) == 0)
  270                                 continue;
  271 
  272                         if ((pd[j] & PG_PS) != 0) {
  273                                 /* This is an entire 2M page. */
  274                                 pa = pd[j] & PG_PS_FRAME;
  275                                 for (k = 0; k < NPTEPG; k++) {
  276                                         if (is_dumpable(pa))
  277                                                 dump_add_page(pa);
  278                                         pa += PAGE_SIZE;
  279                                 }
  280                                 continue;
  281                         }
  282 
  283                         pa = pd[j] & PG_FRAME;
  284                         /* set bit for this PTE page */
  285                         if (is_dumpable(pa))
  286                                 dump_add_page(pa);
  287                         /* and for each valid page in this 2MB block */
  288                         pt = (uint64_t *)PHYS_TO_DMAP(pd[j] & PG_FRAME);
  289                         for (k = 0; k < NPTEPG; k++) {
  290                                 if ((pt[k] & PG_V) == 0)
  291                                         continue;
  292                                 pa = pt[k] & PG_FRAME;
  293                                 if (is_dumpable(pa))
  294                                         dump_add_page(pa);
  295                         }
  296                 }
  297         }
  298 
  299         /* Calculate dump size. */
  300         dumpsize = pmapsize;
  301         dumpsize += round_page(msgbufp->msg_size);
  302         dumpsize += round_page(vm_page_dump_size);
  303         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
  304                 bits = vm_page_dump[i];
  305                 while (bits) {
  306                         bit = bsfq(bits);
  307                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE;
  308                         /* Clear out undumpable pages now if needed */
  309                         if (is_dumpable(pa)) {
  310                                 dumpsize += PAGE_SIZE;
  311                         } else {
  312                                 dump_drop_page(pa);
  313                         }
  314                         bits &= ~(1ul << bit);
  315                 }
  316         }
  317         dumpsize += PAGE_SIZE;
  318 
  319         /* Determine dump offset on device. */
  320         if (di->mediasize < SIZEOF_METADATA + dumpsize + di->blocksize * 2) {
  321                 error = E2BIG;
  322                 goto fail;
  323         }
  324         dumplo = di->mediaoffset + di->mediasize - dumpsize;
  325         dumplo -= di->blocksize * 2;
  326         progress = dumpsize;
  327 
  328         /* Initialize mdhdr */
  329         bzero(&mdhdr, sizeof(mdhdr));
  330         strcpy(mdhdr.magic, MINIDUMP_MAGIC);
  331         mdhdr.version = MINIDUMP_VERSION;
  332         mdhdr.msgbufsize = msgbufp->msg_size;
  333         mdhdr.bitmapsize = vm_page_dump_size;
  334         mdhdr.pmapsize = pmapsize;
  335         mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
  336         mdhdr.dmapbase = DMAP_MIN_ADDRESS;
  337         mdhdr.dmapend = DMAP_MAX_ADDRESS;
  338 
  339         mkdumpheader(&kdh, KERNELDUMPMAGIC, KERNELDUMP_AMD64_VERSION, dumpsize, di->blocksize);
  340 
  341         printf("Dumping %llu out of %ju MB:", (long long)dumpsize >> 20,
  342             ptoa((uintmax_t)physmem) / 1048576);
  343 
  344         /* Dump leader */
  345         error = dump_write_pad(di, &kdh, 0, dumplo, sizeof(kdh), &size);
  346         if (error)
  347                 goto fail;
  348         dumplo += size;
  349 
  350         /* Dump my header */
  351         bzero(&fakepd, sizeof(fakepd));
  352         bcopy(&mdhdr, &fakepd, sizeof(mdhdr));
  353         error = blk_write(di, (char *)&fakepd, 0, PAGE_SIZE);
  354         if (error)
  355                 goto fail;
  356 
  357         /* Dump msgbuf up front */
  358         error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
  359         if (error)
  360                 goto fail;
  361 
  362         /* Dump bitmap */
  363         error = blk_write(di, (char *)vm_page_dump, 0, round_page(vm_page_dump_size));
  364         if (error)
  365                 goto fail;
  366 
  367         /* Dump kernel page directory pages */
  368         bzero(fakepd, sizeof(fakepd));
  369         for (va = VM_MIN_KERNEL_ADDRESS; va < MAX(KERNBASE + nkpt * NBPDR,
  370             kernel_vm_end); va += NBPDP) {
  371                 ii = pmap_pml4e_index(va);
  372                 pml4 = (uint64_t *)PHYS_TO_DMAP(KPML4phys) + ii;
  373                 pdp = (uint64_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
  374                 i = pmap_pdpe_index(va);
  375 
  376                 /* We always write a page, even if it is zero */
  377                 if ((pdp[i] & PG_V) == 0) {
  378                         error = blk_write(di, (char *)&fakepd, 0, PAGE_SIZE);
  379                         if (error)
  380                                 goto fail;
  381                         /* flush, in case we reuse fakepd in the same block */
  382                         error = blk_flush(di);
  383                         if (error)
  384                                 goto fail;
  385                         continue;
  386                 }
  387 
  388                 /* 1GB page is represented as 512 2MB pages in a dump */
  389                 if ((pdp[i] & PG_PS) != 0) {
  390                         /* PDPE and PDP have identical layout in this case */
  391                         fakepd[0] = pdp[i];
  392                         for (j = 1; j < NPDEPG; j++)
  393                                 fakepd[j] = fakepd[j - 1] + NBPDR;
  394                         error = blk_write(di, (char *)&fakepd, 0, PAGE_SIZE);
  395                         if (error)
  396                                 goto fail;
  397                         /* flush, in case we reuse fakepd in the same block */
  398                         error = blk_flush(di);
  399                         if (error)
  400                                 goto fail;
  401                         bzero(fakepd, sizeof(fakepd));
  402                         continue;
  403                 }
  404 
  405                 pd = (uint64_t *)PHYS_TO_DMAP(pdp[i] & PG_FRAME);
  406                 error = blk_write(di, (char *)pd, 0, PAGE_SIZE);
  407                 if (error)
  408                         goto fail;
  409                 error = blk_flush(di);
  410                 if (error)
  411                         goto fail;
  412         }
  413 
  414         /* Dump memory chunks */
  415         /* XXX cluster it up and use blk_dump() */
  416         for (i = 0; i < vm_page_dump_size / sizeof(*vm_page_dump); i++) {
  417                 bits = vm_page_dump[i];
  418                 while (bits) {
  419                         bit = bsfq(bits);
  420                         pa = (((uint64_t)i * sizeof(*vm_page_dump) * NBBY) + bit) * PAGE_SIZE;
  421                         error = blk_write(di, 0, pa, PAGE_SIZE);
  422                         if (error)
  423                                 goto fail;
  424                         bits &= ~(1ul << bit);
  425                 }
  426         }
  427 
  428         error = blk_flush(di);
  429         if (error)
  430                 goto fail;
  431 
  432         /* Dump trailer */
  433         error = dump_write_pad(di, &kdh, 0, dumplo, sizeof(kdh), &size);
  434         if (error)
  435                 goto fail;
  436         dumplo += size;
  437 
  438         /* Signal completion, signoff and exit stage left. */
  439         dump_write(di, NULL, 0, 0, 0);
  440         printf("\nDump complete\n");
  441         return (0);
  442 
  443  fail:
  444         if (error < 0)
  445                 error = -error;
  446 
  447         printf("\n");
  448         if (error == ENOSPC) {
  449                 printf("Dump map grown while dumping. ");
  450                 if (retry_count < 5) {
  451                         printf("Retrying...\n");
  452                         goto retry;
  453                 }
  454                 printf("Dump failed.\n");
  455         }
  456         else if (error == ECANCELED)
  457                 printf("Dump aborted\n");
  458         else if (error == E2BIG)
  459                 printf("Dump failed. Partition too small.\n");
  460         else
  461                 printf("** DUMP FAILED (ERROR %d) **\n", error);
  462         return (error);
  463 }
  464 
  465 void
  466 dump_add_page(vm_paddr_t pa)
  467 {
  468         int idx, bit;
  469 
  470         pa >>= PAGE_SHIFT;
  471         idx = pa >> 6;          /* 2^6 = 64 */
  472         bit = pa & 63;
  473         atomic_set_long(&vm_page_dump[idx], 1ul << bit);
  474 }
  475 
  476 void
  477 dump_drop_page(vm_paddr_t pa)
  478 {
  479         int idx, bit;
  480 
  481         pa >>= PAGE_SHIFT;
  482         idx = pa >> 6;          /* 2^6 = 64 */
  483         bit = pa & 63;
  484         atomic_clear_long(&vm_page_dump[idx], 1ul << bit);
  485 }

Cache object: 5a791461750a1342e0b5e5f1afc7c047


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.