WebSVN – HelenOS-historic – Blame – /kernel/trunk/genarch/src/mm/page_pt.c

Rev	Author	Line No.	Line
684	jermar	1	/*
		2	* Copyright (C) 2006 Jakub Jermar
		3	* All rights reserved.
		4	*
		5	* Redistribution and use in source and binary forms, with or without
		6	* modification, are permitted provided that the following conditions
		7	* are met:
		8	*
		9	* - Redistributions of source code must retain the above copyright
		10	* notice, this list of conditions and the following disclaimer.
		11	* - Redistributions in binary form must reproduce the above copyright
		12	* notice, this list of conditions and the following disclaimer in the
		13	* documentation and/or other materials provided with the distribution.
		14	* - The name of the author may not be used to endorse or promote products
		15	* derived from this software without specific prior written permission.
		16	*
		17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
		18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
		19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
		20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
		21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
		22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
		23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
		24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
		25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
		26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
		27	*/
		28
		29	#include <genarch/mm/page_pt.h>
		30	#include <mm/page.h>
		31	#include <mm/frame.h>
756	jermar	32	#include <mm/as.h>
684	jermar	33	#include <arch/mm/page.h>
755	jermar	34	#include <arch/mm/as.h>
684	jermar	35	#include <arch/types.h>
		36	#include <typedefs.h>
		37	#include <arch/asm.h>
		38	#include <memstr.h>
		39
756	jermar	40	static void pt_mapping_insert(as_t *as, __address page, __address frame, int flags);
		41	static pte_t pt_mapping_find(as_t as, __address page);
684	jermar	42
793	jermar	43	page_mapping_operations_t pt_mapping_operations = {
684	jermar	44	.mapping_insert = pt_mapping_insert,
		45	.mapping_find = pt_mapping_find
		46	};
		47
		48	/** Map page to frame using hierarchical page tables.
		49	*
		50	* Map virtual address 'page' to physical address 'frame'
		51	* using 'flags'.
		52	*
756	jermar	53	* The address space must be locked and interrupts must be disabled.
		54	*
		55	* @param as Address space to wich page belongs.
684	jermar	56	* @param page Virtual address of the page to be mapped.
		57	* @param frame Physical address of memory frame to which the mapping is done.
		58	* @param flags Flags to be used for mapping.
		59	*/
756	jermar	60	void pt_mapping_insert(as_t *as, __address page, __address frame, int flags)
684	jermar	61	{
		62	pte_t ptl0, ptl1, ptl2, ptl3;
		63	__address newpt;
		64
756	jermar	65	ptl0 = (pte_t *) PA2KA((__address) as->page_table);
684	jermar	66
		67	if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {
814	palkovsky	68	newpt = PA2KA(PFN2ADDR(frame_alloc(ONE_FRAME, FRAME_KA)));
684	jermar	69	memsetb(newpt, PAGE_SIZE, 0);
		70	SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));
		71	SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
		72	}
		73
		74	ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
		75
		76	if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {
814	palkovsky	77	newpt = PA2KA(PFN2ADDR(frame_alloc(ONE_FRAME, FRAME_KA)));
684	jermar	78	memsetb(newpt, PAGE_SIZE, 0);
		79	SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));
		80	SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
		81	}
		82
		83	ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
		84
		85	if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {
814	palkovsky	86	newpt = PA2KA(PFN2ADDR(frame_alloc(ONE_FRAME, FRAME_KA)));
684	jermar	87	memsetb(newpt, PAGE_SIZE, 0);
		88	SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));
		89	SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT \| PAGE_USER \| PAGE_EXEC \| PAGE_CACHEABLE \| PAGE_WRITE);
		90	}
		91
		92	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
		93
		94	SET_FRAME_ADDRESS(ptl3, PTL3_INDEX(page), frame);
		95	SET_FRAME_FLAGS(ptl3, PTL3_INDEX(page), flags);
		96	}
		97
		98	/** Find mapping for virtual page in hierarchical page tables.
		99	*
		100	* Find mapping for virtual page.
		101	*
756	jermar	102	* The address space must be locked and interrupts must be disabled.
		103	*
		104	* @param as Address space to which page belongs.
684	jermar	105	* @param page Virtual page.
		106	*
		107	* @return NULL if there is no such mapping; entry from PTL3 describing the mapping otherwise.
		108	*/
756	jermar	109	pte_t pt_mapping_find(as_t as, __address page)
684	jermar	110	{
		111	pte_t ptl0, ptl1, ptl2, ptl3;
		112
756	jermar	113	ptl0 = (pte_t *) PA2KA((__address) as->page_table);
684	jermar	114
		115	if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT)
		116	return NULL;
		117
		118	ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
		119
		120	if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT)
		121	return NULL;
		122
		123	ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
		124
		125	if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT)
		126	return NULL;
		127
		128	ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
		129
		130	return &ptl3[PTL3_INDEX(page)];
		131	}

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