/*-
 * 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: stable/11/lib/libkvm/kvm_minidump_mips.c 316126 2017-03-29 07:30:59Z ngie $");

/*
 * 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 == NULL) {
		_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
#ifdef __mips__
_mips_native(kvm_t *kd)
#else
_mips_native(kvm_t *kd __unused)
#endif
{

#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
}

static 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);