/*
Copyright 2025 Kamil Kowalczyk

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 copyright holder 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
HOLDER 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_MM_H
#define _SYS_MM_H

#include <libk/util.h>
#include <libk/types.h>
#include <libk/compiler.h>
#include <sync/spinlock.h>

#define VIRT_BASE   0xC0000000

#define PAGE_SIZE 0x1000

#define PF_PRESENT    (1<<0)
#define PF_WRITABLE   (1<<1)
#define PF_USER       (1<<2)
#define PF_LOCK       (1<<31) /* Special flag for internal usage that doesn't exist in x86.
                                 I use this here, because when (un)mapping an entire page range
                                 it would be inefficient to constantly (un)lock. */

#define KERNEL_HEAP_START       0xF0000000

struct page_dir {
  volatile uint32_t *pd;
  uint16_t pt_refcount[1024];
  struct spinlock sl;
};

void mm_init(void);

void mm_map_page(struct page_dir *pd, uptr_t vaddr, uptr_t paddr, uint32_t flags);
void mm_unmap_page(struct page_dir *pd, uptr_t vaddr, uint32_t flags);
uptr_t mm_translate_v2p(struct page_dir *pd, uptr_t vaddr, uint32_t flags);
uptr_t mm_translate_p2v(struct page_dir *pd, uptr_t paddr, uint32_t flags);
void mm_load_pd(struct page_dir *pd);
struct page_dir *mm_get_kernel_pd(void);

#endif // _SYS_MM_H