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-rw-r--r--lib/libkvm/kvm_i386.c454
1 files changed, 454 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_i386.c b/lib/libkvm/kvm_i386.c
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+++ b/lib/libkvm/kvm_i386.c
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+/*-
+ * Copyright (c) 1989, 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software developed by the Computer Systems
+ * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
+ * BG 91-66 and contributed to Berkeley.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#if defined(LIBC_SCCS) && !defined(lint)
+#if 0
+static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * i386 machine dependent routines for kvm. Hopefully, the forthcoming
+ * vm code will one day obsolete this module.
+ */
+
+#include <sys/param.h>
+#include <sys/user.h>
+#include <sys/proc.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <nlist.h>
+#include <kvm.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+
+#include <machine/elf.h>
+
+#include <limits.h>
+
+#include "kvm_private.h"
+
+#ifndef btop
+#define btop(x) (i386_btop(x))
+#define ptob(x) (i386_ptob(x))
+#endif
+
+#define PG_FRAME_PAE (~((uint64_t)PAGE_MASK))
+#define PDRSHIFT_PAE 21
+#define NPTEPG_PAE (PAGE_SIZE/sizeof(uint64_t))
+#define NBPDR_PAE (1<<PDRSHIFT_PAE)
+
+/* minidump must be the first item! */
+struct vmstate {
+ int minidump; /* 1 = minidump mode */
+ void *mmapbase;
+ size_t mmapsize;
+ void *PTD;
+ int pae;
+};
+
+/*
+ * Map the ELF headers into the process' address space. We do this in two
+ * steps: first the ELF header itself and using that information the whole
+ * set of headers. (Taken from kvm_ia64.c)
+ */
+static int
+_kvm_maphdrs(kvm_t *kd, size_t sz)
+{
+ struct vmstate *vm = kd->vmst;
+
+ /* munmap() previous mmap(). */
+ if (vm->mmapbase != NULL) {
+ munmap(vm->mmapbase, vm->mmapsize);
+ vm->mmapbase = NULL;
+ }
+
+ vm->mmapsize = sz;
+ vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
+ if (vm->mmapbase == MAP_FAILED) {
+ _kvm_err(kd, kd->program, "cannot mmap corefile");
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * Translate a physical memory address to a file-offset in the crash-dump.
+ * (Taken from kvm_ia64.c)
+ */
+static size_t
+_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs)
+{
+ Elf_Ehdr *e = kd->vmst->mmapbase;
+ Elf_Phdr *p;
+ int n;
+
+ if (kd->rawdump) {
+ *ofs = pa;
+ return (PAGE_SIZE - ((size_t)pa & PAGE_MASK));
+ }
+
+ p = (Elf_Phdr*)((char*)e + e->e_phoff);
+ n = e->e_phnum;
+ while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
+ p++, n--;
+ if (n == 0)
+ return (0);
+ *ofs = (pa - p->p_paddr) + p->p_offset;
+ return (PAGE_SIZE - ((size_t)pa & PAGE_MASK));
+}
+
+void
+_kvm_freevtop(kvm_t *kd)
+{
+ struct vmstate *vm = kd->vmst;
+
+ if (kd->vmst->minidump)
+ return (_kvm_minidump_freevtop(kd));
+ if (vm->mmapbase != NULL)
+ munmap(vm->mmapbase, vm->mmapsize);
+ if (vm->PTD)
+ free(vm->PTD);
+ free(vm);
+ kd->vmst = NULL;
+}
+
+int
+_kvm_initvtop(kvm_t *kd)
+{
+ struct nlist nl[2];
+ u_long pa;
+ u_long kernbase;
+ char *PTD;
+ Elf_Ehdr *ehdr;
+ size_t hdrsz;
+ int i;
+ char minihdr[8];
+
+ if (!kd->rawdump && pread(kd->pmfd, &minihdr, 8, 0) == 8)
+ if (memcmp(&minihdr, "minidump", 8) == 0)
+ return (_kvm_minidump_initvtop(kd));
+
+ kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
+ if (kd->vmst == 0) {
+ _kvm_err(kd, kd->program, "cannot allocate vm");
+ return (-1);
+ }
+ kd->vmst->PTD = 0;
+
+ if (kd->rawdump == 0) {
+ if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1)
+ return (-1);
+
+ ehdr = kd->vmst->mmapbase;
+ hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum;
+ if (_kvm_maphdrs(kd, hdrsz) == -1)
+ return (-1);
+ }
+
+ nl[0].n_name = "kernbase";
+ nl[1].n_name = 0;
+
+ if (kvm_nlist(kd, nl) != 0)
+ kernbase = KERNBASE; /* for old kernels */
+ else
+ kernbase = nl[0].n_value;
+
+ nl[0].n_name = "IdlePDPT";
+ nl[1].n_name = 0;
+
+ if (kvm_nlist(kd, nl) == 0) {
+ uint64_t pa64;
+
+ if (kvm_read(kd, (nl[0].n_value - kernbase), &pa,
+ sizeof(pa)) != sizeof(pa)) {
+ _kvm_err(kd, kd->program, "cannot read IdlePDPT");
+ return (-1);
+ }
+ PTD = _kvm_malloc(kd, 4 * PAGE_SIZE);
+ for (i = 0; i < 4; i++) {
+ if (kvm_read(kd, pa + (i * sizeof(pa64)), &pa64,
+ sizeof(pa64)) != sizeof(pa64)) {
+ _kvm_err(kd, kd->program, "Cannot read PDPT");
+ free(PTD);
+ return (-1);
+ }
+ if (kvm_read(kd, pa64 & PG_FRAME_PAE,
+ PTD + (i * PAGE_SIZE), PAGE_SIZE) != (PAGE_SIZE)) {
+ _kvm_err(kd, kd->program, "cannot read PDPT");
+ free(PTD);
+ return (-1);
+ }
+ }
+ kd->vmst->PTD = PTD;
+ kd->vmst->pae = 1;
+ } else {
+ nl[0].n_name = "IdlePTD";
+ nl[1].n_name = 0;
+
+ if (kvm_nlist(kd, nl) != 0) {
+ _kvm_err(kd, kd->program, "bad namelist");
+ return (-1);
+ }
+ if (kvm_read(kd, (nl[0].n_value - kernbase), &pa,
+ sizeof(pa)) != sizeof(pa)) {
+ _kvm_err(kd, kd->program, "cannot read IdlePTD");
+ return (-1);
+ }
+ PTD = _kvm_malloc(kd, PAGE_SIZE);
+ if (kvm_read(kd, pa, PTD, PAGE_SIZE) != PAGE_SIZE) {
+ _kvm_err(kd, kd->program, "cannot read PTD");
+ return (-1);
+ }
+ kd->vmst->PTD = PTD;
+ return (0);
+ kd->vmst->pae = 0;
+ }
+ return (0);
+}
+
+static int
+_kvm_vatop(kvm_t *kd, u_long va, off_t *pa)
+{
+ struct vmstate *vm;
+ u_long offset;
+ u_long pte_pa;
+ u_long pde_pa;
+ pd_entry_t pde;
+ pt_entry_t pte;
+ u_long pdeindex;
+ u_long pteindex;
+ size_t s;
+ u_long a;
+ off_t ofs;
+ uint32_t *PTD;
+
+ vm = kd->vmst;
+ PTD = (uint32_t *)vm->PTD;
+ offset = va & (PAGE_SIZE - 1);
+
+ /*
+ * If we are initializing (kernel page table descriptor pointer
+ * not yet set) then return pa == va to avoid infinite recursion.
+ */
+ if (PTD == 0) {
+ s = _kvm_pa2off(kd, va, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop: bootstrap data not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
+ }
+
+ pdeindex = va >> PDRSHIFT;
+ pde = PTD[pdeindex];
+ if (((u_long)pde & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pde not valid");
+ goto invalid;
+ }
+
+ if ((u_long)pde & PG_PS) {
+ /*
+ * No second-level page table; ptd describes one 4MB page.
+ * (We assume that the kernel wouldn't set PG_PS without enabling
+ * it cr0).
+ */
+#define PAGE4M_MASK (NBPDR - 1)
+#define PG_FRAME4M (~PAGE4M_MASK)
+ pde_pa = ((u_long)pde & PG_FRAME4M) + (va & PAGE4M_MASK);
+ s = _kvm_pa2off(kd, pde_pa, &ofs);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop: 4MB page address not in dump");
+ goto invalid;
+ }
+ *pa = ofs;
+ return (NBPDR - (va & PAGE4M_MASK));
+ }
+
+ pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1);
+ pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pde));
+
+ s = _kvm_pa2off(kd, pte_pa, &ofs);
+ if (s < sizeof pte) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found");
+ goto invalid;
+ }
+
+ /* XXX This has to be a physical address read, kvm_read is virtual */
+ if (lseek(kd->pmfd, ofs, 0) == -1) {
+ _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek");
+ goto invalid;
+ }
+ if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) {
+ _kvm_syserr(kd, kd->program, "_kvm_vatop: read");
+ goto invalid;
+ }
+ if (((u_long)pte & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_kvatop: pte not valid");
+ goto invalid;
+ }
+
+ a = ((u_long)pte & PG_FRAME) + offset;
+ s =_kvm_pa2off(kd, a, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop: address not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
+
+invalid:
+ _kvm_err(kd, 0, "invalid address (0x%lx)", va);
+ return (0);
+}
+
+static int
+_kvm_vatop_pae(kvm_t *kd, u_long va, off_t *pa)
+{
+ struct vmstate *vm;
+ uint64_t offset;
+ uint64_t pte_pa;
+ uint64_t pde_pa;
+ uint64_t pde;
+ uint64_t pte;
+ u_long pdeindex;
+ u_long pteindex;
+ size_t s;
+ uint64_t a;
+ off_t ofs;
+ uint64_t *PTD;
+
+ vm = kd->vmst;
+ PTD = (uint64_t *)vm->PTD;
+ offset = va & (PAGE_SIZE - 1);
+
+ /*
+ * If we are initializing (kernel page table descriptor pointer
+ * not yet set) then return pa == va to avoid infinite recursion.
+ */
+ if (PTD == 0) {
+ s = _kvm_pa2off(kd, va, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop_pae: bootstrap data not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
+ }
+
+ pdeindex = va >> PDRSHIFT_PAE;
+ pde = PTD[pdeindex];
+ if (((u_long)pde & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_kvatop_pae: pde not valid");
+ goto invalid;
+ }
+
+ if ((u_long)pde & PG_PS) {
+ /*
+ * No second-level page table; ptd describes one 2MB page.
+ * (We assume that the kernel wouldn't set PG_PS without enabling
+ * it cr0).
+ */
+#define PAGE2M_MASK (NBPDR_PAE - 1)
+#define PG_FRAME2M (~PAGE2M_MASK)
+ pde_pa = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK);
+ s = _kvm_pa2off(kd, pde_pa, &ofs);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop: 2MB page address not in dump");
+ goto invalid;
+ }
+ *pa = ofs;
+ return (NBPDR_PAE - (va & PAGE2M_MASK));
+ }
+
+ pteindex = (va >> PAGE_SHIFT) & (NPTEPG_PAE-1);
+ pte_pa = ((uint64_t)pde & PG_FRAME_PAE) + (pteindex * sizeof(pde));
+
+ s = _kvm_pa2off(kd, pte_pa, &ofs);
+ if (s < sizeof pte) {
+ _kvm_err(kd, kd->program, "_kvm_vatop_pae: pdpe_pa not found");
+ goto invalid;
+ }
+
+ /* XXX This has to be a physical address read, kvm_read is virtual */
+ if (lseek(kd->pmfd, ofs, 0) == -1) {
+ _kvm_syserr(kd, kd->program, "_kvm_vatop_pae: lseek");
+ goto invalid;
+ }
+ if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) {
+ _kvm_syserr(kd, kd->program, "_kvm_vatop_pae: read");
+ goto invalid;
+ }
+ if (((uint64_t)pte & PG_V) == 0) {
+ _kvm_err(kd, kd->program, "_kvm_vatop_pae: pte not valid");
+ goto invalid;
+ }
+
+ a = ((uint64_t)pte & PG_FRAME_PAE) + offset;
+ s =_kvm_pa2off(kd, a, pa);
+ if (s == 0) {
+ _kvm_err(kd, kd->program,
+ "_kvm_vatop_pae: address not in dump");
+ goto invalid;
+ } else
+ return (PAGE_SIZE - offset);
+
+invalid:
+ _kvm_err(kd, 0, "invalid address (0x%lx)", va);
+ return (0);
+}
+
+int
+_kvm_kvatop(kvm_t *kd, u_long va, off_t *pa)
+{
+
+ if (kd->vmst->minidump)
+ return (_kvm_minidump_kvatop(kd, va, pa));
+ if (ISALIVE(kd)) {
+ _kvm_err(kd, 0, "vatop called in live kernel!");
+ return (0);
+ }
+ if (kd->vmst->pae)
+ return (_kvm_vatop_pae(kd, va, pa));
+ else
+ return (_kvm_vatop(kd, va, pa));
+}
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