| Current Path : /usr/src/lib/libkvm/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libkvm/kvm_i386.c |
/*-
* 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: release/9.1.0/lib/libkvm/kvm_i386.c 217744 2011-01-23 11:08:28Z uqs $");
#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));
}