freebsd-skq/lib/libkvm/kvm_powerpc.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

238 lines
6.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2008, Juniper Networks, Inc.
* All rights reserved.
*
* 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 author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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("$FreeBSD$");
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/kerneldump.h>
#include <sys/mman.h>
#include <elf.h>
#include <kvm.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include "kvm_private.h"
struct vmstate {
void *map;
size_t mapsz;
size_t dmphdrsz;
Elf32_Ehdr *eh;
Elf32_Phdr *ph;
};
static int
valid_elf_header(Elf32_Ehdr *eh)
{
if (!IS_ELF(*eh))
return (0);
if (eh->e_ident[EI_CLASS] != ELFCLASS32)
return (0);
if (eh->e_ident[EI_DATA] != ELFDATA2MSB)
return (0);
if (eh->e_ident[EI_VERSION] != EV_CURRENT)
return (0);
if (eh->e_ident[EI_OSABI] != ELFOSABI_STANDALONE)
return (0);
if (be16toh(eh->e_type) != ET_CORE)
return (0);
if (be16toh(eh->e_machine) != EM_PPC)
return (0);
/* Can't think of anything else to check... */
return (1);
}
static size_t
dump_header_size(struct kerneldumpheader *dh)
{
if (strcmp(dh->magic, KERNELDUMPMAGIC) != 0)
return (0);
if (strcmp(dh->architecture, "powerpc") != 0)
return (0);
/* That should do it... */
return (sizeof(*dh));
}
/*
* 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
powerpc_maphdrs(kvm_t *kd)
{
struct vmstate *vm;
size_t mapsz;
vm = kd->vmst;
vm->mapsz = sizeof(*vm->eh) + sizeof(struct kerneldumpheader);
vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
if (vm->map == MAP_FAILED) {
_kvm_err(kd, kd->program, "cannot map corefile");
return (-1);
}
vm->dmphdrsz = 0;
vm->eh = vm->map;
if (!valid_elf_header(vm->eh)) {
/*
* Hmmm, no ELF header. Maybe we still have a dump header.
* This is normal when the core file wasn't created by
* savecore(8), but instead was dumped over TFTP. We can
* easily skip the dump header...
*/
vm->dmphdrsz = dump_header_size(vm->map);
if (vm->dmphdrsz == 0)
goto inval;
vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz);
if (!valid_elf_header(vm->eh))
goto inval;
}
mapsz = be16toh(vm->eh->e_phentsize) * be16toh(vm->eh->e_phnum) +
be32toh(vm->eh->e_phoff);
munmap(vm->map, vm->mapsz);
/* Map all headers. */
vm->mapsz = vm->dmphdrsz + mapsz;
vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
if (vm->map == MAP_FAILED) {
_kvm_err(kd, kd->program, "cannot map corefile headers");
return (-1);
}
vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz);
vm->ph = (void *)((uintptr_t)vm->eh + be32toh(vm->eh->e_phoff));
return (0);
inval:
_kvm_err(kd, kd->program, "invalid corefile");
return (-1);
}
/*
* Determine the offset within the corefile corresponding the virtual
* address. Return the number of contiguous bytes in the corefile or
* 0 when the virtual address is invalid.
*/
static size_t
powerpc_va2off(kvm_t *kd, kvaddr_t va, off_t *ofs)
{
struct vmstate *vm = kd->vmst;
Elf32_Phdr *ph;
int nph;
ph = vm->ph;
nph = be16toh(vm->eh->e_phnum);
while (nph && (va < be32toh(ph->p_vaddr) ||
va >= be32toh(ph->p_vaddr) + be32toh(ph->p_memsz))) {
nph--;
ph = (void *)((uintptr_t)ph + be16toh(vm->eh->e_phentsize));
}
if (nph == 0)
return (0);
/* Segment found. Return file offset and range. */
*ofs = vm->dmphdrsz + be32toh(ph->p_offset) +
(va - be32toh(ph->p_vaddr));
return (be32toh(ph->p_memsz) - (va - be32toh(ph->p_vaddr)));
}
static void
_powerpc_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm->eh != MAP_FAILED)
munmap(vm->eh, vm->mapsz);
free(vm);
kd->vmst = NULL;
}
static int
_powerpc_probe(kvm_t *kd)
{
return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_PPC) &&
kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB);
}
static int
_powerpc_initvtop(kvm_t *kd)
{
kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
if (kd->vmst == NULL)
return (-1);
if (powerpc_maphdrs(kd) == -1)
return (-1);
return (0);
}
static int
_powerpc_kvatop(kvm_t *kd, kvaddr_t va, off_t *ofs)
{
struct vmstate *vm;
vm = kd->vmst;
if (be32toh(vm->ph->p_paddr) == 0xffffffff)
return ((int)powerpc_va2off(kd, va, ofs));
_kvm_err(kd, kd->program, "Raw corefile not supported");
return (0);
}
static int
_powerpc_native(kvm_t *kd __unused)
{
#if defined(__powerpc__) && !defined(__powerpc64__)
return (1);
#else
return (0);
#endif
}
static struct kvm_arch kvm_powerpc = {
.ka_probe = _powerpc_probe,
.ka_initvtop = _powerpc_initvtop,
.ka_freevtop = _powerpc_freevtop,
.ka_kvatop = _powerpc_kvatop,
.ka_native = _powerpc_native,
};
KVM_ARCH(kvm_powerpc);