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/* $FreeBSD$ */
/* $NetBSD: kvm_alpha.c,v 1.7.2.1 1997/11/02 20:34:26 mellon Exp $ */
/*
* Copyright (c) 1994, 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Chris G. Demetriou
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <sys/types.h>
#include <sys/elf64.h>
#include <sys/mman.h>
#include <machine/pte.h>
#include <kvm.h>
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include "kvm_private.h"
#define REGION_BASE(n) (((uint64_t)(n)) << 61)
#define REGION_ADDR(x) ((x) & ((1LL<<61)-1LL))
#define NKPTEPG(ps) ((ps) / sizeof(struct ia64_lpte))
#define KPTE_PTE_INDEX(va,ps) (((va)/(ps)) % NKPTEPG(ps))
#define KPTE_DIR_INDEX(va,ps) (((va)/(ps)) / NKPTEPG(ps))
struct vmstate {
void *mmapbase;
size_t mmapsize;
size_t pagesize;
u_long kptdir;
};
/*
* 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.
*/
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.
*/
static size_t
_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs, size_t pgsz)
{
Elf64_Ehdr *e = kd->vmst->mmapbase;
Elf64_Phdr *p = (Elf64_Phdr*)((char*)e + e->e_phoff);
int n = e->e_phnum;
if (pa != REGION_ADDR(pa)) {
_kvm_err(kd, kd->program, "internal error");
return (0);
}
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;
if (pgsz == 0)
return (p->p_memsz - (pa - p->p_paddr));
return (pgsz - ((size_t)pa & (pgsz - 1)));
}
void
_kvm_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm->mmapbase != NULL)
munmap(vm->mmapbase, vm->mmapsize);
free(vm);
kd->vmst = NULL;
}
int
_kvm_initvtop(kvm_t *kd)
{
struct nlist nlist[2];
uint64_t va;
Elf64_Ehdr *ehdr;
size_t hdrsz;
kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
if (kd->vmst == NULL) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
kd->vmst->pagesize = getpagesize();
if (_kvm_maphdrs(kd, sizeof(Elf64_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);
/*
* At this point we've got enough information to use kvm_read() for
* direct mapped (ie region 6 and region 7) address, such as symbol
* addresses/values.
*/
nlist[0].n_name = "ia64_kptdir";
nlist[1].n_name = 0;
if (kvm_nlist(kd, nlist) != 0) {
_kvm_err(kd, kd->program, "bad namelist");
return (-1);
}
if (kvm_read(kd, (nlist[0].n_value), &va, sizeof(va)) != sizeof(va)) {
_kvm_err(kd, kd->program, "cannot read kptdir");
return (-1);
}
if (va < REGION_BASE(6)) {
_kvm_err(kd, kd->program, "kptdir is itself virtual");
return (-1);
}
kd->vmst->kptdir = va;
return (0);
}
int
_kvm_kvatop(kvm_t *kd, u_long va, off_t *pa)
{
struct ia64_lpte pte;
uint64_t pgaddr, ptaddr;
size_t pgno, pgsz, ptno;
if (va >= REGION_BASE(6)) {
/* Regions 6 and 7: direct mapped. */
return (_kvm_pa2off(kd, REGION_ADDR(va), pa, 0));
} else if (va >= REGION_BASE(5)) {
/* Region 5: virtual. */
va = REGION_ADDR(va);
pgsz = kd->vmst->pagesize;
ptno = KPTE_DIR_INDEX(va, pgsz);
pgno = KPTE_PTE_INDEX(va, pgsz);
if (ptno >= (pgsz >> 3))
goto fail;
ptaddr = kd->vmst->kptdir + (ptno << 3);
if (kvm_read(kd, ptaddr, &pgaddr, 8) != 8)
goto fail;
if (pgaddr == 0)
goto fail;
pgaddr += (pgno * sizeof(pte));
if (kvm_read(kd, pgaddr, &pte, sizeof(pte)) != sizeof(pte))
goto fail;
if (!(pte.pte & PTE_PRESENT))
goto fail;
va = (pte.pte & PTE_PPN_MASK) + (va & (pgsz - 1));
return (_kvm_pa2off(kd, va, pa, pgsz));
}
fail:
_kvm_err(kd, kd->program, "invalid kernel virtual address");
*pa = ~0UL;
return (0);
}
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