/*
* 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.
*/
#include <mm/page.h>
#include <mm/frame.h>
#include <arch/mm/page.h>
#include <arch/types.h>
#include <typedefs.h>
#include <arch/asm.h>
#include <memstr.h>
void page_init(void)
{
page_arch_init();
page_mapping_insert(0x0, 0x0, PAGE_NOT_PRESENT, 0);
}
/** Map memory structure
*
* Identity-map memory structure
* considering possible crossings
* of page boundaries.
*
* @param s Address of the structure.
* @param size Size of the structure.
*/
void map_structure(__address s, size_t size)
{
int i, cnt, length;
length = size + (s - (s & ~(PAGE_SIZE-1)));
cnt = length/PAGE_SIZE + (length%PAGE_SIZE>0);
for (i = 0; i < cnt; i++)
page_mapping_insert(s + i*PAGE_SIZE, s + i*PAGE_SIZE, PAGE_NOT_CACHEABLE, 0);
}
/** Map page to frame
*
* Map virtual address 'page' to physical address 'frame'
* using 'flags'. Allocate and setup any missing page tables.
*
* @param page Virtual address of the page to be mapped.
* @param frame Physical address of memory frame to which the mapping is done.
* @param flags Flags to be used for mapping.
* @param root Explicit PTL0 address.
*/
void page_mapping_insert(__address page, __address frame, int flags, __address root)
{
pte_t *ptl0, *ptl1, *ptl2, *ptl3;
__address newpt;
ptl0 = (pte_t *) PA2KA(root ? root : (__address) GET_PTL0_ADDRESS());
if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {
newpt = frame_alloc(FRAME_KA, ONE_FRAME);
memsetb(newpt, PAGE_SIZE, 0);
SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));
SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE);
}
ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {
newpt = frame_alloc(FRAME_KA, ONE_FRAME);
memsetb(newpt, PAGE_SIZE, 0);
SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));
SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE);
}
ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {
newpt = frame_alloc(FRAME_KA, ONE_FRAME);
memsetb(newpt, PAGE_SIZE, 0);
SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));
SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE);
}
ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
SET_FRAME_ADDRESS(ptl3, PTL3_INDEX(page), frame);
SET_FRAME_FLAGS(ptl3, PTL3_INDEX(page), flags);
}
/** Find mapping for virtual page
*
* Find mapping for virtual page.
*
* @param page Virtual page.
* @param root PTL0 address if non-zero.
*
* @return NULL if there is no such mapping; entry from PTL3 describing the mapping otherwise.
*/
pte_t *page_mapping_find(__address page, __address root)
{
pte_t *ptl0, *ptl1, *ptl2, *ptl3;
ptl0 = (pte_t *) PA2KA(root ? root : (__address) GET_PTL0_ADDRESS());
if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT)
return NULL;
ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT)
return NULL;
ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT)
return NULL;
ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
return &ptl3[PTL3_INDEX(page)];
}