/*
* Copyright (C) 2006 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 <genarch/mm/page_pt.h>
#include <mm/page.h>
#include <mm/frame.h>
#include <mm/as.h>
#include <arch/mm/page.h>
#include <arch/mm/as.h>
#include <arch/types.h>
#include <typedefs.h>
#include <memstr.h>
#include <arch.h>
static pte_t *ptl0_create(int flags);
static void pt_lock(as_t *as, bool lock);
static void pt_unlock(as_t *as, bool unlock);
as_operations_t as_pt_operations = {
.page_table_create = ptl0_create,
.page_table_lock = pt_lock,
.page_table_unlock = pt_unlock
};
/** Create PTL0.
*
* PTL0 of 4-level page table will be created for each address space.
*
* @param flags Flags can specify whether ptl0 is for the kernel address space.
*
* @return New PTL0.
*/
pte_t *ptl0_create(int flags)
{
pte_t *src_ptl0, *dst_ptl0;
ipl_t ipl;
dst_ptl0 = (pte_t *) PA2KA(PFN2ADDR(frame_alloc(ONE_FRAME, FRAME_KA | FRAME_PANIC)));
if (flags & FLAG_AS_KERNEL) {
memsetb((__address) dst_ptl0, PAGE_SIZE, 0);
} else {
/*
* Copy the kernel address space portion to new PTL0.
* TODO: copy only kernel address space.
*/
ipl = interrupts_disable();
spinlock_lock(&AS_KERNEL->lock);
src_ptl0 = (pte_t *) PA2KA((__address) AS_KERNEL->page_table);
memcpy((void *) dst_ptl0
,(void *) src_ptl0
, PAGE_SIZE
);
spinlock_unlock(&AS_KERNEL->lock);
interrupts_restore(ipl);
}
return (pte_t *) KA2PA((__address) dst_ptl0);
}
/** Lock page tables.
*
* Lock only the address space.
* Interrupts must be disabled.
*
* @param as Address space.
* @param lock If false, do not attempt to lock the address space.
*/
void pt_lock(as_t *as, bool lock)
{
if (lock)
spinlock_lock(&as->lock);
}
/** Unlock page tables.
*
* Unlock the address space.
* Interrupts must be disabled.
*
* @param as Address space.
* @param unlock If false, do not attempt to unlock the address space.
*/
void pt_unlock(as_t *as, bool unlock)
{
if (unlock)
spinlock_unlock(&as->lock);
}