/*
* 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.
*/
/** @addtogroup kernel_genarch_mm
* @{
*/
/**
* @file
* @brief Address space functions for global page hash table.
*/
#include <arch/mm/as.h>
#include <genarch/mm/as_ht.h>
#include <genarch/mm/page_ht.h>
#include <mm/as.h>
#include <mm/frame.h>
#include <mm/slab.h>
#include <typedefs.h>
#include <adt/hash_table.h>
#include <synch/mutex.h>
static pte_t *ht_create(unsigned int);
static void ht_destroy(pte_t *);
static void ht_lock(as_t *, bool);
static void ht_unlock(as_t *, bool);
static bool ht_locked(as_t *);
const as_operations_t as_ht_operations = {
.page_table_create = ht_create,
.page_table_destroy = ht_destroy,
.page_table_lock = ht_lock,
.page_table_unlock = ht_unlock,
.page_table_locked = ht_locked,
};
/** Page hash table create.
*
* The page hash table will be created only once
* and will be shared by all address spaces.
*
* @param flags Ignored.
*
* @return Returns NULL.
*
*/
pte_t *ht_create(unsigned int flags)
{
if (flags & FLAG_AS_KERNEL) {
hash_table_create(&page_ht, 0, 0, &ht_ops);
pte_cache = slab_cache_create("pte_t", sizeof(pte_t), 0,
NULL, NULL, SLAB_CACHE_MAGDEFERRED);
}
return NULL;
}
/** Destroy page table.
*
* Actually do nothing as the global page hash table is used.
*
* @param page_table This parameter is ignored.
*
*/
void ht_destroy(pte_t *page_table)
{
/* No-op. */
}
/** Lock page table.
*
* Lock address space.
* Interrupts must be disabled.
*
* @param as Address space.
* @param lock If false, do not attempt to lock the address space.
*
*/
void ht_lock(as_t *as, bool lock)
{
if (lock)
mutex_lock(&as->lock);
}
/** Unlock page table.
*
* Unlock address space.
* Interrupts must be disabled.
*
* @param as Address space.
* @param unlock If false, do not attempt to lock the address space.
*
*/
void ht_unlock(as_t *as, bool unlock)
{
if (unlock)
mutex_unlock(&as->lock);
}
/** Test whether page tables are locked.
*
* @param as Address space where the page tables belong.
*
* @return True if the page tables belonging to the address soace
* are locked, otherwise false.
*/
bool ht_locked(as_t *as)
{
return mutex_locked(&as->lock);
}
/** @}
*/