freebsd-skq/lib/libkvm/kvm_minidump_mips.c
John Baldwin 7f911abe54 Add support to libkvm for reading vmcores from other architectures.
- Add a kvaddr_type to represent kernel virtual addresses instead of
  unsigned long.
- Add a struct kvm_nlist which is a stripped down version of struct nlist
  that uses kvaddr_t for n_value.
- Add a kvm_native() routine that returns true if an open kvm descriptor
  is for a native kernel and memory image.
- Add a kvm_open2() function similar to kvm_openfiles().  It drops the
  unused 'swapfile' argument and adds a new function pointer argument for
  a symbol resolving function.  Native kernels still use _fdnlist() from
  libc to resolve symbols if a resolver function is not supplied, but cross
  kernels require a resolver.
- Add a kvm_nlist2() function similar to kvm_nlist() except that it uses
  struct kvm_nlist instead of struct nlist.
- Add a kvm_read2() function similar to kvm_read() except that it uses
  kvaddr_t instead of unsigned long for the kernel virtual address.
- Add a new kvm_arch switch of routines needed by a vmcore backend.
  Each backend is responsible for implementing kvm_read2() for a given
  vmcore format.
- Use libelf to read headers from ELF kernels and cores (except for
  powerpc cores).
- Add internal helper routines for the common page offset hash table used
  by the minidump backends.
- Port all of the existing kvm backends to implement a kvm_arch switch and
  to be cross-friendly by using private constants instead of ones that
  vary by platform (e.g. PAGE_SIZE).  Static assertions are present when
  a given backend is compiled natively to ensure the private constants
  match the real ones.
- Enable all of the existing vmcore backends on all platforms.  This means
  that libkvm on any platform should be able to perform KVA translation
  and read data from a vmcore of any platform.

Tested on:	amd64, i386, sparc64 (marius)
Differential Revision:	https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00

296 lines
7.6 KiB
C

/*-
* Copyright (c) 2010 Oleksandr Tymoshenko
* Copyright (c) 2008 Semihalf, Grzegorz Bernacki
* Copyright (c) 2006 Peter Wemm
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* From: FreeBSD: src/lib/libkvm/kvm_minidump_arm.c r214223
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* MIPS machine dependent routines for kvm and minidumps.
*/
#include <sys/param.h>
#include <kvm.h>
#include <limits.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "../../sys/mips/include/cpuregs.h"
#include "../../sys/mips/include/minidump.h"
#include "kvm_private.h"
#include "kvm_mips.h"
#define mips_round_page(x) roundup2((kvaddr_t)(x), MIPS_PAGE_SIZE)
struct vmstate {
struct minidumphdr hdr;
struct hpt hpt;
void *ptemap;
int pte_size;
};
static int
_mips_minidump_probe(kvm_t *kd)
{
if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS32 &&
kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS64)
return (0);
if (kd->nlehdr.e_machine != EM_MIPS)
return (0);
return (_kvm_is_minidump(kd));
}
static void
_mips_minidump_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
_kvm_hpt_free(&vm->hpt);
if (vm->ptemap)
free(vm->ptemap);
free(vm);
kd->vmst = NULL;
}
static int
_mips_minidump_initvtop(kvm_t *kd)
{
struct vmstate *vmst;
uint32_t *bitmap;
off_t off;
vmst = _kvm_malloc(kd, sizeof(*vmst));
if (vmst == 0) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
kd->vmst = vmst;
if (kd->nlehdr.e_ident[EI_CLASS] == ELFCLASS64 ||
kd->nlehdr.e_flags & EF_MIPS_ABI2)
vmst->pte_size = 64;
else
vmst->pte_size = 32;
if (pread(kd->pmfd, &vmst->hdr,
sizeof(vmst->hdr), 0) != sizeof(vmst->hdr)) {
_kvm_err(kd, kd->program, "cannot read dump header");
return (-1);
}
if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
sizeof(vmst->hdr.magic)) != 0) {
_kvm_err(kd, kd->program, "not a minidump for this platform");
return (-1);
}
vmst->hdr.version = _kvm32toh(kd, vmst->hdr.version);
if (vmst->hdr.version != MINIDUMP_VERSION) {
_kvm_err(kd, kd->program, "wrong minidump version. "
"Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
return (-1);
}
vmst->hdr.msgbufsize = _kvm32toh(kd, vmst->hdr.msgbufsize);
vmst->hdr.bitmapsize = _kvm32toh(kd, vmst->hdr.bitmapsize);
vmst->hdr.ptesize = _kvm32toh(kd, vmst->hdr.ptesize);
vmst->hdr.kernbase = _kvm64toh(kd, vmst->hdr.kernbase);
vmst->hdr.dmapbase = _kvm64toh(kd, vmst->hdr.dmapbase);
vmst->hdr.dmapend = _kvm64toh(kd, vmst->hdr.dmapend);
/* Skip header and msgbuf */
off = MIPS_PAGE_SIZE + mips_round_page(vmst->hdr.msgbufsize);
bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
if (bitmap == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for "
"bitmap", vmst->hdr.bitmapsize);
return (-1);
}
if (pread(kd->pmfd, bitmap, vmst->hdr.bitmapsize, off) !=
(ssize_t)vmst->hdr.bitmapsize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap",
vmst->hdr.bitmapsize);
free(bitmap);
return (-1);
}
off += mips_round_page(vmst->hdr.bitmapsize);
vmst->ptemap = _kvm_malloc(kd, vmst->hdr.ptesize);
if (vmst->ptemap == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for "
"ptemap", vmst->hdr.ptesize);
free(bitmap);
return (-1);
}
if (pread(kd->pmfd, vmst->ptemap, vmst->hdr.ptesize, off) !=
(ssize_t)vmst->hdr.ptesize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for ptemap",
vmst->hdr.ptesize);
free(bitmap);
return (-1);
}
off += vmst->hdr.ptesize;
/* Build physical address hash table for sparse pages */
_kvm_hpt_init(kd, &vmst->hpt, bitmap, vmst->hdr.bitmapsize, off,
MIPS_PAGE_SIZE, sizeof(*bitmap));
free(bitmap);
return (0);
}
static int
_mips_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
struct vmstate *vm;
uint64_t pte;
mips_physaddr_t offset, a;
kvaddr_t pteindex;
off_t ofs;
uint32_t *ptemap32;
uint64_t *ptemap64;
if (ISALIVE(kd)) {
_kvm_err(kd, 0, "_mips_minidump_kvatop called in live kernel!");
return (0);
}
offset = va & MIPS_PAGE_MASK;
/* Operate with page-aligned address */
va &= ~MIPS_PAGE_MASK;
vm = kd->vmst;
ptemap32 = vm->ptemap;
ptemap64 = vm->ptemap;
if (kd->nlehdr.e_ident[EI_CLASS] == ELFCLASS64) {
if (va >= MIPS_XKPHYS_START && va < MIPS_XKPHYS_END) {
a = va & MIPS_XKPHYS_PHYS_MASK;
goto found;
}
if (va >= MIPS64_KSEG0_START && va < MIPS64_KSEG0_END) {
a = va & MIPS_KSEG0_PHYS_MASK;
goto found;
}
if (va >= MIPS64_KSEG1_START && va < MIPS64_KSEG1_END) {
a = va & MIPS_KSEG0_PHYS_MASK;
goto found;
}
} else {
if (va >= MIPS32_KSEG0_START && va < MIPS32_KSEG0_END) {
a = va & MIPS_KSEG0_PHYS_MASK;
goto found;
}
if (va >= MIPS32_KSEG1_START && va < MIPS32_KSEG1_END) {
a = va & MIPS_KSEG0_PHYS_MASK;
goto found;
}
}
if (va >= vm->hdr.kernbase) {
pteindex = (va - vm->hdr.kernbase) >> MIPS_PAGE_SHIFT;
if (vm->pte_size == 64) {
pte = _kvm64toh(kd, ptemap64[pteindex]);
a = MIPS64_PTE_TO_PA(pte);
} else {
pte = _kvm32toh(kd, ptemap32[pteindex]);
a = MIPS32_PTE_TO_PA(pte);
}
if (!pte) {
_kvm_err(kd, kd->program, "_mips_minidump_kvatop: pte "
"not valid");
goto invalid;
}
} else {
_kvm_err(kd, kd->program, "_mips_minidump_kvatop: virtual "
"address 0x%jx not minidumped", (uintmax_t)va);
return (0);
}
found:
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_mips_minidump_kvatop: physical "
"address 0x%jx not in minidump", (uintmax_t)a);
goto invalid;
}
*pa = ofs + offset;
return (MIPS_PAGE_SIZE - offset);
invalid:
_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
return (0);
}
static int
_mips_native(kvm_t *kd)
{
#ifdef __mips__
#ifdef __mips_n64
if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS64)
return (0);
#else
if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS32)
return (0);
#ifdef __mips_n32
if (!(kd->nlehdr.e_flags & EF_MIPS_ABI2))
return (0);
#else
if (kd->nlehdr.e_flags & EF_MIPS_ABI2)
return (0);
#endif
#endif
#if _BYTE_ORDER == _LITTLE_ENDIAN
return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB);
#else
return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB);
#endif
#else
return (0);
#endif
}
struct kvm_arch kvm_mips_minidump = {
.ka_probe = _mips_minidump_probe,
.ka_initvtop = _mips_minidump_initvtop,
.ka_freevtop = _mips_minidump_freevtop,
.ka_kvatop = _mips_minidump_kvatop,
.ka_native = _mips_native,
};
KVM_ARCH(kvm_mips_minidump);