LXR linux/arch/hexagon/include/asm/mmu

   1/*
   2 * MM context support for the Hexagon architecture
   3 *
   4 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 and
   8 * only version 2 as published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write to the Free Software
  17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18 * 02110-1301, USA.
  19 */
  20
  21#ifndef _ASM_MMU_CONTEXT_H
  22#define _ASM_MMU_CONTEXT_H
  23
  24#include <asm/setup.h>
  25#include <asm/page.h>
  26#include <asm/pgalloc.h>
  27#include <asm/mem-layout.h>
  28
  29static inline void destroy_context(struct mm_struct *mm)
  30{
  31}
  32
  33/*
  34 * VM port hides all TLB management, so "lazy TLB" isn't very
  35 * meaningful.  Even for ports to architectures with visble TLBs,
  36 * this is almost invariably a null function.
  37 */
  38static inline void enter_lazy_tlb(struct mm_struct *mm,
  39        struct task_struct *tsk)
  40{
  41}
  42
  43/*
  44 * Architecture-specific actions, if any, for memory map deactivation.
  45 */
  46static inline void deactivate_mm(struct task_struct *tsk,
  47        struct mm_struct *mm)
  48{
  49}
  50
  51/**
  52 * init_new_context - initialize context related info for new mm_struct instance
  53 * @tsk: pointer to a task struct
  54 * @mm: pointer to a new mm struct
  55 */
  56static inline int init_new_context(struct task_struct *tsk,
  57                                        struct mm_struct *mm)
  58{
  59        /* mm->context is set up by pgd_alloc */
  60        return 0;
  61}
  62
  63/*
  64 *  Switch active mm context
  65 */
  66static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  67                                struct task_struct *tsk)
  68{
  69        int l1;
  70
  71        /*
  72         * For virtual machine, we have to update system map if it's been
  73         * touched.
  74         */
  75        if (next->context.generation < prev->context.generation) {
  76                for (l1 = MIN_KERNEL_SEG; l1 <= max_kernel_seg; l1++)
  77                        next->pgd[l1] = init_mm.pgd[l1];
  78
  79                next->context.generation = prev->context.generation;
  80        }
  81
  82        __vmnewmap((void *)next->context.ptbase);
  83}
  84
  85/*
  86 *  Activate new memory map for task
  87 */
  88static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
  89{
  90        unsigned long flags;
  91
  92        local_irq_save(flags);
  93        switch_mm(prev, next, current_thread_info()->task);
  94        local_irq_restore(flags);
  95}
  96
  97/*  Generic hooks for arch_dup_mmap and arch_exit_mmap  */
  98#include <asm-generic/mm_hooks.h>
  99
 100#endif
 101