freebsd-nq/lib/libkvm/kvm_i386.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

434 lines
10 KiB
C

/*-
* 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.
*/
#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/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);