linux-sg2042/include/asm-blackfin/mmu_context.h

130 lines
3.3 KiB
C

/*
* File: include/asm-blackfin/mmu_context.h
* Based on:
* Author:
*
* Created:
* Description:
*
* Modified:
* Copyright 2004-2006 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __BLACKFIN_MMU_CONTEXT_H__
#define __BLACKFIN_MMU_CONTEXT_H__
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
extern void *current_l1_stack_save;
extern int nr_l1stack_tasks;
extern void *l1_stack_base;
extern unsigned long l1_stack_len;
extern int l1sram_free(const void*);
extern void *l1sram_alloc_max(void*);
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
/* Called when creating a new context during fork() or execve(). */
static inline int
init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
return 0;
}
static inline void free_l1stack(void)
{
nr_l1stack_tasks--;
if (nr_l1stack_tasks == 0)
l1sram_free(l1_stack_base);
}
static inline void destroy_context(struct mm_struct *mm)
{
struct sram_list_struct *tmp;
if (current_l1_stack_save == mm->context.l1_stack_save)
current_l1_stack_save = 0;
if (mm->context.l1_stack_save)
free_l1stack();
while ((tmp = mm->context.sram_list)) {
mm->context.sram_list = tmp->next;
sram_free(tmp->addr);
kfree(tmp);
}
}
static inline unsigned long
alloc_l1stack(unsigned long length, unsigned long *stack_base)
{
if (nr_l1stack_tasks == 0) {
l1_stack_base = l1sram_alloc_max(&l1_stack_len);
if (!l1_stack_base)
return 0;
}
if (l1_stack_len < length) {
if (nr_l1stack_tasks == 0)
l1sram_free(l1_stack_base);
return 0;
}
*stack_base = (unsigned long)l1_stack_base;
nr_l1stack_tasks++;
return l1_stack_len;
}
static inline int
activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
{
if (current_l1_stack_save)
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
return 1;
}
#define deactivate_mm(tsk,mm) do { } while (0)
static inline void activate_mm(struct mm_struct *prev_mm,
struct mm_struct *next_mm)
{
if (!next_mm->context.l1_stack_save)
return;
if (next_mm->context.l1_stack_save == current_l1_stack_save)
return;
if (current_l1_stack_save) {
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
}
current_l1_stack_save = next_mm->context.l1_stack_save;
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
activate_mm(prev, next);
}
#endif