diff options
Diffstat (limited to 'lib/libkvm/kvm_amd64.c')
| -rw-r--r-- | lib/libkvm/kvm_amd64.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_amd64.c b/lib/libkvm/kvm_amd64.c new file mode 100644 index 0000000..65d697c --- /dev/null +++ b/lib/libkvm/kvm_amd64.c @@ -0,0 +1,357 @@ +/*- + * 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 */ + +/* + * AMD64 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) (amd64_btop(x)) +#define ptob(x) (amd64_ptob(x)) +#endif + +/* minidump must be the first item! */ +struct vmstate { + int minidump; /* 1 = minidump mode */ + void *mmapbase; + size_t mmapsize; + pml4_entry_t *PML4; +}; + +/* + * 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->PML4) + free(vm->PML4); + free(vm); + kd->vmst = NULL; +} + +int +_kvm_initvtop(kvm_t *kd) +{ + struct nlist nl[2]; + u_long pa; + u_long kernbase; + pml4_entry_t *PML4; + Elf_Ehdr *ehdr; + size_t hdrsz; + 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->PML4 = 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) { + _kvm_err(kd, kd->program, "bad namelist - no kernbase"); + return (-1); + } + kernbase = nl[0].n_value; + + nl[0].n_name = "KPML4phys"; + nl[1].n_name = 0; + + if (kvm_nlist(kd, nl) != 0) { + _kvm_err(kd, kd->program, "bad namelist - no KPML4phys"); + return (-1); + } + if (kvm_read(kd, (nl[0].n_value - kernbase), &pa, sizeof(pa)) != + sizeof(pa)) { + _kvm_err(kd, kd->program, "cannot read KPML4phys"); + return (-1); + } + PML4 = _kvm_malloc(kd, PAGE_SIZE); + if (kvm_read(kd, pa, PML4, PAGE_SIZE) != PAGE_SIZE) { + _kvm_err(kd, kd->program, "cannot read KPML4phys"); + return (-1); + } + kd->vmst->PML4 = PML4; + return (0); +} + +static int +_kvm_vatop(kvm_t *kd, u_long va, off_t *pa) +{ + struct vmstate *vm; + u_long offset; + u_long pdpe_pa; + u_long pde_pa; + u_long pte_pa; + pml4_entry_t pml4e; + pdp_entry_t pdpe; + pd_entry_t pde; + pt_entry_t pte; + u_long pml4eindex; + u_long pdpeindex; + u_long pdeindex; + u_long pteindex; + u_long a; + off_t ofs; + size_t s; + + vm = kd->vmst; + 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 (vm->PML4 == 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); + } + + pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1); + pml4e = vm->PML4[pml4eindex]; + if (((u_long)pml4e & PG_V) == 0) { + _kvm_err(kd, kd->program, "_kvm_vatop: pml4e not valid"); + goto invalid; + } + + pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1); + pdpe_pa = ((u_long)pml4e & PG_FRAME) + + (pdpeindex * sizeof(pdp_entry_t)); + + s = _kvm_pa2off(kd, pdpe_pa, &ofs); + if (s < sizeof pdpe) { + _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found"); + goto invalid; + } + if (lseek(kd->pmfd, ofs, 0) == -1) { + _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa"); + goto invalid; + } + if (read(kd->pmfd, &pdpe, sizeof pdpe) != sizeof pdpe) { + _kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe"); + goto invalid; + } + if (((u_long)pdpe & PG_V) == 0) { + _kvm_err(kd, kd->program, "_kvm_vatop: pdpe not valid"); + goto invalid; + } + + pdeindex = (va >> PDRSHIFT) & (NPDEPG-1); + pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t)); + + s = _kvm_pa2off(kd, pde_pa, &ofs); + if (s < sizeof pde) { + _kvm_syserr(kd, kd->program, "_kvm_vatop: pde_pa not found"); + goto invalid; + } + if (lseek(kd->pmfd, ofs, 0) == -1) { + _kvm_err(kd, kd->program, "_kvm_vatop: lseek pde_pa"); + goto invalid; + } + if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) { + _kvm_syserr(kd, kd->program, "_kvm_vatop: read pde"); + goto invalid; + } + 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 final-level page table; ptd describes one 2MB page. + */ +#define PAGE2M_MASK (NBPDR - 1) +#define PG_FRAME2M (~PAGE2M_MASK) + a = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK); + s = _kvm_pa2off(kd, a, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_kvm_vatop: 2MB page address not in dump"); + goto invalid; + } else + return (NBPDR - (va & PAGE2M_MASK)); + } + + pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1); + pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t)); + + s = _kvm_pa2off(kd, pte_pa, &ofs); + if (s < sizeof pte) { + _kvm_err(kd, kd->program, "_kvm_vatop: pte_pa not found"); + goto invalid; + } + 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_vatop: 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); +} + +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, "kvm_kvatop called in live kernel!"); + return (0); + } + return (_kvm_vatop(kd, va, pa)); +} |
