/*
 * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
 * 
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 * 
 * 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 DragonFly Project 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 COPYRIGHT HOLDERS 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
 * COPYRIGHT HOLDERS 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.
 */

#ifndef _SYS_VKERNEL_H_
#define _SYS_VKERNEL_H_

#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
/*
 * KERNEL ONLY DEFINITIONS
 */

#ifndef _SYS_PARAM_H_
#include <sys/param.h>
#endif
#ifndef _SYS_QUEUE_H_
#include <sys/queue.h>
#endif
#ifndef _SYS_TREE_H_
#include <sys/tree.h>
#endif
#ifndef _SYS_SPINLOCK_H_
#include <sys/spinlock.h>
#endif
#ifndef _SYS_THREAD_H_
#include <sys/thread.h>
#endif
#include <machine/frame.h>
#include <machine/vframe.h>
#include <machine/limits.h>

struct vmspace_rb_tree;
struct vmspace_entry;
struct lwp;
RB_PROTOTYPE(vmspace_rb_tree, vmspace_entry, rb_entry, rb_vmspace_compare);

/*
 * Process operating as virtual kernels manage multiple VM spaces.  The
 * original VM space and trap context is saved in the process's vkernel
 * structure.
 */
#define VE_CACHE_COUNT  4               /* power of 2 */

struct vkernel_lwp {
        struct trapframe save_trapframe;        /* swapped context */
        struct vextframe save_vextframe;
        struct trapframe *user_trapframe;       /* copyback to vkernel */
        struct vextframe *user_vextframe;
        struct vmspace_entry *ve;
        struct vmspace_entry *ve_cache[VE_CACHE_COUNT];
        int     ve_cache_rover;
        int     ve_unused01;
};


struct vkernel_proc {
        RB_HEAD(vmspace_rb_tree, vmspace_entry) root;
        struct lwkt_token token;
        int refs;
        register_t vkernel_cr3;
};

struct vmspace_entry {
        void *id;
        struct vmspace *vmspace;
        uint32_t flags;
        uint32_t refs;                  /* in-use + 1(on-tree */
        uint32_t cache_refs;            /* cache count (separate) */
        RB_ENTRY(vmspace_entry) rb_entry;
};

#define VKE_REF_DELETED 0x80000000U

#ifdef _KERNEL

void vkernel_inherit(struct proc *p1, struct proc *p2);
void vkernel_exit(struct proc *p);
void vkernel_lwp_exit(struct lwp *lp);
void vkernel_trap(struct lwp *lp, struct trapframe *frame);

#endif

#else
/*
 * USER ONLY DEFINITIONS
 */

#ifndef _MACHINE_PARAM_H_
#include <machine/param.h>
#endif

#endif

/*
 * KERNEL AND USER DEFINITIONS
 *
 * WARNING: vpte_t is 64 bits.  A 4-layer page table is used.
 */
typedef u_long  vpte_t;

#if LONG_BIT == 32
#define VPTE_FRAME_END          32
#define VPTE_PAGE_BITS          10
#define VPTE_FRAME              0xFFFFF000L
#elif LONG_BIT == 64
#define VPTE_FRAME_END          48
#define VPTE_PAGE_BITS          9
#define VPTE_FRAME              0x000FFFFFFFFFF000L
#else
#error "LONG_BIT not defined"
#endif

#define VPTE_PAGE_ENTRIES       (PAGE_SIZE / sizeof(vpte_t))
#define VPTE_PAGE_MASK          ((1 << VPTE_PAGE_BITS) - 1)
#define VPTE_PAGETABLE_SIZE     PAGE_SIZE

#define VPTE_V          0x00000001      /* valid */
#define VPTE_RW         0x00000002      /* read/write */
#define VPTE_U          0x00000004      /* user access bit if managed vmspace */

#define VPTE_A          0x00000020      /* page accessed bit */
#define VPTE_M          0x00000040      /* page modified bit */
#define VPTE_PS         0x00000080      /* page directory direct mapping */

#define VPTE_G          0x00000100      /* global bit ?? */
#define VPTE_WIRED      0x00000200      /* wired */
#define VPTE_MANAGED    0x00000400      /* managed bit ?? */
#define VPTE_NX         0x00000800      /* no-execute bit */

#endif