diff options
Diffstat (limited to 'lib/libkvm/kvm_i386.c')
| -rw-r--r-- | lib/libkvm/kvm_i386.c | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_i386.c b/lib/libkvm/kvm_i386.c new file mode 100644 index 000000000000..776c486579a1 --- /dev/null +++ b/lib/libkvm/kvm_i386.c @@ -0,0 +1,425 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * 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. + * 3. 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. + */ + + +/* + * i386 machine dependent routines for kvm. Hopefully, the forthcoming + * vm code will one day obsolete this module. + */ + +#include <sys/param.h> +#include <sys/endian.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <vm/vm.h> +#include <kvm.h> + +#ifdef __i386__ +#include <machine/vmparam.h> /* For KERNBASE. */ +#endif + +#include <limits.h> + +#include "kvm_private.h" +#include "kvm_i386.h" + +struct vmstate { + void *PTD; + int pae; + size_t phnum; + GElf_Phdr *phdr; +}; + +/* + * Translate a physical memory address to a file-offset in the crash-dump. + */ +static size_t +_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs) +{ + struct vmstate *vm = kd->vmst; + GElf_Phdr *p; + size_t n; + + if (kd->rawdump) { + *ofs = pa; + return (I386_PAGE_SIZE - (pa & I386_PAGE_MASK)); + } + + p = vm->phdr; + n = vm->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 (I386_PAGE_SIZE - (pa & I386_PAGE_MASK)); +} + +static void +_i386_freevtop(kvm_t *kd) +{ + struct vmstate *vm = kd->vmst; + + if (vm->PTD) + free(vm->PTD); + free(vm->phdr); + free(vm); + kd->vmst = NULL; +} + +static int +_i386_probe(kvm_t *kd) +{ + + return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_386) && + !_kvm_is_minidump(kd)); +} + +static int +_i386_initvtop(kvm_t *kd) +{ + struct kvm_nlist nl[2]; + i386_physaddr_t pa; + kvaddr_t kernbase; + char *PTD; + int i; + + kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(struct vmstate)); + if (kd->vmst == NULL) { + _kvm_err(kd, kd->program, "cannot allocate vm"); + return (-1); + } + kd->vmst->PTD = 0; + + if (kd->rawdump == 0) { + if (_kvm_read_core_phdrs(kd, &kd->vmst->phnum, + &kd->vmst->phdr) == -1) + return (-1); + } + + nl[0].n_name = "kernbase"; + nl[1].n_name = 0; + + if (kvm_nlist2(kd, nl) != 0) { +#ifdef __i386__ + kernbase = KERNBASE; /* for old kernels */ +#else + _kvm_err(kd, kd->program, "cannot resolve kernbase"); + return (-1); +#endif + } else + kernbase = nl[0].n_value; + + nl[0].n_name = "IdlePDPT"; + nl[1].n_name = 0; + + if (kvm_nlist2(kd, nl) == 0) { + i386_physaddr_pae_t pa64; + + if (kvm_read2(kd, (nl[0].n_value - kernbase), &pa, + sizeof(pa)) != sizeof(pa)) { + _kvm_err(kd, kd->program, "cannot read IdlePDPT"); + return (-1); + } + pa = le32toh(pa); + PTD = _kvm_malloc(kd, 4 * I386_PAGE_SIZE); + if (PTD == NULL) { + _kvm_err(kd, kd->program, "cannot allocate PTD"); + return (-1); + } + for (i = 0; i < 4; i++) { + if (kvm_read2(kd, pa + (i * sizeof(pa64)), &pa64, + sizeof(pa64)) != sizeof(pa64)) { + _kvm_err(kd, kd->program, "Cannot read PDPT"); + free(PTD); + return (-1); + } + pa64 = le64toh(pa64); + if (kvm_read2(kd, pa64 & I386_PG_FRAME_PAE, + PTD + (i * I386_PAGE_SIZE), I386_PAGE_SIZE) != + I386_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_nlist2(kd, nl) != 0) { + _kvm_err(kd, kd->program, "bad namelist"); + return (-1); + } + if (kvm_read2(kd, (nl[0].n_value - kernbase), &pa, + sizeof(pa)) != sizeof(pa)) { + _kvm_err(kd, kd->program, "cannot read IdlePTD"); + return (-1); + } + pa = le32toh(pa); + PTD = _kvm_malloc(kd, I386_PAGE_SIZE); + if (PTD == NULL) { + _kvm_err(kd, kd->program, "cannot allocate PTD"); + return (-1); + } + if (kvm_read2(kd, pa, PTD, I386_PAGE_SIZE) != I386_PAGE_SIZE) { + _kvm_err(kd, kd->program, "cannot read PTD"); + return (-1); + } + kd->vmst->PTD = PTD; + kd->vmst->pae = 0; + } + return (0); +} + +static int +_i386_vatop(kvm_t *kd, kvaddr_t va, off_t *pa) +{ + struct vmstate *vm; + i386_physaddr_t offset; + i386_physaddr_t pte_pa; + i386_pde_t pde; + i386_pte_t pte; + kvaddr_t pdeindex; + kvaddr_t pteindex; + size_t s; + i386_physaddr_t a; + off_t ofs; + i386_pde_t *PTD; + + vm = kd->vmst; + PTD = (i386_pde_t *)vm->PTD; + offset = va & I386_PAGE_MASK; + + /* + * If we are initializing (kernel page table descriptor pointer + * not yet set) then return pa == va to avoid infinite recursion. + */ + if (PTD == NULL) { + s = _kvm_pa2off(kd, va, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_i386_vatop: bootstrap data not in dump"); + goto invalid; + } else + return (I386_PAGE_SIZE - offset); + } + + pdeindex = va >> I386_PDRSHIFT; + pde = le32toh(PTD[pdeindex]); + if ((pde & I386_PG_V) == 0) { + _kvm_err(kd, kd->program, "_i386_vatop: pde not valid"); + goto invalid; + } + + if (pde & I386_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). + */ + offset = va & I386_PAGE_PS_MASK; + a = (pde & I386_PG_PS_FRAME) + offset; + s = _kvm_pa2off(kd, a, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_i386_vatop: 4MB page address not in dump"); + goto invalid; + } + return (I386_NBPDR - offset); + } + + pteindex = (va >> I386_PAGE_SHIFT) & (I386_NPTEPG - 1); + pte_pa = (pde & I386_PG_FRAME) + (pteindex * sizeof(pte)); + + s = _kvm_pa2off(kd, pte_pa, &ofs); + if (s < sizeof(pte)) { + _kvm_err(kd, kd->program, "_i386_vatop: pte_pa not found"); + goto invalid; + } + + /* XXX This has to be a physical address read, kvm_read is virtual */ + if (pread(kd->pmfd, &pte, sizeof(pte), ofs) != sizeof(pte)) { + _kvm_syserr(kd, kd->program, "_i386_vatop: pread"); + goto invalid; + } + pte = le32toh(pte); + if ((pte & I386_PG_V) == 0) { + _kvm_err(kd, kd->program, "_kvm_kvatop: pte not valid"); + goto invalid; + } + + a = (pte & I386_PG_FRAME) + offset; + s = _kvm_pa2off(kd, a, pa); + if (s == 0) { + _kvm_err(kd, kd->program, "_i386_vatop: address not in dump"); + goto invalid; + } else + return (I386_PAGE_SIZE - offset); + +invalid: + _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); + return (0); +} + +static int +_i386_vatop_pae(kvm_t *kd, kvaddr_t va, off_t *pa) +{ + struct vmstate *vm; + i386_physaddr_pae_t offset; + i386_physaddr_pae_t pte_pa; + i386_pde_pae_t pde; + i386_pte_pae_t pte; + kvaddr_t pdeindex; + kvaddr_t pteindex; + size_t s; + i386_physaddr_pae_t a; + off_t ofs; + i386_pde_pae_t *PTD; + + vm = kd->vmst; + PTD = (i386_pde_pae_t *)vm->PTD; + offset = va & I386_PAGE_MASK; + + /* + * If we are initializing (kernel page table descriptor pointer + * not yet set) then return pa == va to avoid infinite recursion. + */ + if (PTD == NULL) { + s = _kvm_pa2off(kd, va, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_i386_vatop_pae: bootstrap data not in dump"); + goto invalid; + } else + return (I386_PAGE_SIZE - offset); + } + + pdeindex = va >> I386_PDRSHIFT_PAE; + pde = le64toh(PTD[pdeindex]); + if ((pde & I386_PG_V) == 0) { + _kvm_err(kd, kd->program, "_kvm_kvatop_pae: pde not valid"); + goto invalid; + } + + if (pde & I386_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). + */ + offset = va & I386_PAGE_PS_MASK_PAE; + a = (pde & I386_PG_PS_FRAME_PAE) + offset; + s = _kvm_pa2off(kd, a, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_i386_vatop: 2MB page address not in dump"); + goto invalid; + } + return (I386_NBPDR_PAE - offset); + } + + pteindex = (va >> I386_PAGE_SHIFT) & (I386_NPTEPG_PAE - 1); + pte_pa = (pde & I386_PG_FRAME_PAE) + (pteindex * sizeof(pde)); + + s = _kvm_pa2off(kd, pte_pa, &ofs); + if (s < sizeof(pte)) { + _kvm_err(kd, kd->program, "_i386_vatop_pae: pdpe_pa not found"); + goto invalid; + } + + /* XXX This has to be a physical address read, kvm_read is virtual */ + if (pread(kd->pmfd, &pte, sizeof(pte), ofs) != sizeof(pte)) { + _kvm_syserr(kd, kd->program, "_i386_vatop_pae: read"); + goto invalid; + } + pte = le64toh(pte); + if ((pte & I386_PG_V) == 0) { + _kvm_err(kd, kd->program, "_i386_vatop_pae: pte not valid"); + goto invalid; + } + + a = (pte & I386_PG_FRAME_PAE) + offset; + s = _kvm_pa2off(kd, a, pa); + if (s == 0) { + _kvm_err(kd, kd->program, + "_i386_vatop_pae: address not in dump"); + goto invalid; + } else + return (I386_PAGE_SIZE - offset); + +invalid: + _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); + return (0); +} + +static int +_i386_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa) +{ + + if (ISALIVE(kd)) { + _kvm_err(kd, 0, "vatop called in live kernel!"); + return (0); + } + if (kd->vmst->pae) + return (_i386_vatop_pae(kd, va, pa)); + else + return (_i386_vatop(kd, va, pa)); +} + +int +_i386_native(kvm_t *kd __unused) +{ + +#ifdef __i386__ + return (1); +#else + return (0); +#endif +} + +static struct kvm_arch kvm_i386 = { + .ka_probe = _i386_probe, + .ka_initvtop = _i386_initvtop, + .ka_freevtop = _i386_freevtop, + .ka_kvatop = _i386_kvatop, + .ka_native = _i386_native, +}; + +KVM_ARCH(kvm_i386); |