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/*

 * Copyright (C) 2001-2004 Jakub Jermar

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * - Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * - 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.

 * - The name of the author may not 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.

 */

 /** @addtogroup ia32mm	

 * @{

 */

/** @file

 */

#ifndef __ia32_PAGE_H__

#define __ia32_PAGE_H__

#include <arch/mm/frame.h>

#define PAGE_WIDTH	FRAME_WIDTH

#define PAGE_SIZE	FRAME_SIZE

#ifdef KERNEL

#ifndef __ASM__

#	define KA2PA(x)	(((uintptr_t) (x)) - 0x80000000)

#	define PA2KA(x)	(((uintptr_t) (x)) + 0x80000000)

#else

#	define KA2PA(x)	((x) - 0x80000000)

#	define PA2KA(x)	((x) + 0x80000000)

#endif

/*

 * Implementation of generic 4-level page table interface.

 * IA-32 has 2-level page tables, so PTL1 and PTL2 are left out.

 */

#define PTL0_ENTRIES_ARCH	1024

#define PTL1_ENTRIES_ARCH	0

#define PTL2_ENTRIES_ARCH	0

#define PTL3_ENTRIES_ARCH	1024

#define PTL0_INDEX_ARCH(vaddr)	(((vaddr)>>22)&0x3ff)

#define PTL1_INDEX_ARCH(vaddr)	0

#define PTL2_INDEX_ARCH(vaddr)	0

#define PTL3_INDEX_ARCH(vaddr)	(((vaddr)>>12)&0x3ff)

#define GET_PTL1_ADDRESS_ARCH(ptl0, i)		((pte_t *)((((pte_t *)(ptl0))[(i)].frame_address)<<12))

#define GET_PTL2_ADDRESS_ARCH(ptl1, i)		(ptl1)

#define GET_PTL3_ADDRESS_ARCH(ptl2, i)		(ptl2)

#define GET_FRAME_ADDRESS_ARCH(ptl3, i)		((uintptr_t)((((pte_t *)(ptl3))[(i)].frame_address)<<12))

#define SET_PTL0_ADDRESS_ARCH(ptl0)		(write_cr3((uintptr_t) (ptl0)))

#define SET_PTL1_ADDRESS_ARCH(ptl0, i, a)	(((pte_t *)(ptl0))[(i)].frame_address = (a)>>12)

#define SET_PTL2_ADDRESS_ARCH(ptl1, i, a)

#define SET_PTL3_ADDRESS_ARCH(ptl2, i, a)

#define SET_FRAME_ADDRESS_ARCH(ptl3, i, a)	(((pte_t *)(ptl3))[(i)].frame_address = (a)>>12)

#define GET_PTL1_FLAGS_ARCH(ptl0, i)		get_pt_flags((pte_t *)(ptl0), (index_t)(i))

#define GET_PTL2_FLAGS_ARCH(ptl1, i)		PAGE_PRESENT

#define GET_PTL3_FLAGS_ARCH(ptl2, i)		PAGE_PRESENT

#define GET_FRAME_FLAGS_ARCH(ptl3, i)		get_pt_flags((pte_t *)(ptl3), (index_t)(i))

#define SET_PTL1_FLAGS_ARCH(ptl0, i, x)		set_pt_flags((pte_t *)(ptl0), (index_t)(i), (x))

#define SET_PTL2_FLAGS_ARCH(ptl1, i, x)

#define SET_PTL3_FLAGS_ARCH(ptl2, i, x)

#define SET_FRAME_FLAGS_ARCH(ptl3, i, x)	set_pt_flags((pte_t *)(ptl3), (index_t)(i), (x))

#define PTE_VALID_ARCH(p)			(*((uint32_t *) (p)) != 0)

#define PTE_PRESENT_ARCH(p)			((p)->present != 0)

#define PTE_GET_FRAME_ARCH(p)			((p)->frame_address<<FRAME_WIDTH)

#define PTE_WRITABLE_ARCH(p)			((p)->writeable != 0)

#define PTE_EXECUTABLE_ARCH(p)			1

#ifndef __ASM__

#include <mm/page.h>

#include <arch/types.h>

#include <arch/mm/frame.h>

#include <typedefs.h>

/* Page fault error codes. */

/** When bit on this position is 0, the page fault was caused by a not-present page. */

#define PFERR_CODE_P		(1<<0)

/** When bit on this position is 1, the page fault was caused by a write. */

#define PFERR_CODE_RW		(1<<1)

/** When bit on this position is 1, the page fault was caused in user mode. */

#define PFERR_CODE_US		(1<<2)

/** When bit on this position is 1, a reserved bit was set in page directory. */ 

#define PFERR_CODE_RSVD		(1<<3)	

/** Page Table Entry. */

struct page_specifier {

	unsigned present : 1;

	unsigned writeable : 1;

	unsigned uaccessible : 1;

	unsigned page_write_through : 1;

	unsigned page_cache_disable : 1;

	unsigned accessed : 1;

	unsigned dirty : 1;

	unsigned pat : 1;

	unsigned global : 1;

	unsigned soft_valid : 1;	/**< Valid content even if the present bit is not set. */

	unsigned avl : 2;

	unsigned frame_address : 20;

} __attribute__ ((packed));

static inline int get_pt_flags(pte_t *pt, index_t i)

{

	pte_t *p = &pt[i];

	return (

		(!p->page_cache_disable)<<PAGE_CACHEABLE_SHIFT |

		(!p->present)<<PAGE_PRESENT_SHIFT |

		p->uaccessible<<PAGE_USER_SHIFT |

		1<<PAGE_READ_SHIFT |

		p->writeable<<PAGE_WRITE_SHIFT |

		1<<PAGE_EXEC_SHIFT |

		p->global<<PAGE_GLOBAL_SHIFT

	);

}

static inline void set_pt_flags(pte_t *pt, index_t i, int flags)

{

	pte_t *p = &pt[i];

	p->page_cache_disable = !(flags & PAGE_CACHEABLE);

	p->present = !(flags & PAGE_NOT_PRESENT);

	p->uaccessible = (flags & PAGE_USER) != 0;

	p->writeable = (flags & PAGE_WRITE) != 0;

	p->global = (flags & PAGE_GLOBAL) != 0;

	/*

	 * Ensure that there is at least one bit set even if the present bit is cleared.

	 */

	p->soft_valid = true;

}

extern void page_arch_init(void);

extern void page_fault(int n, istate_t *istate);

#endif /* __ASM__ */

#endif /* KERNEL */

#endif

 /** @}

 */