tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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 <linux/mm_types.h>
25
26#include <asm/setup.h>
27#include <asm/page.h>
28#include <asm/pgalloc.h>
29#include <asm/mem-layout.h>
30
31static inline void destroy_context(struct mm_struct *mm)
32{
33}
34
35/*
36 * VM port hides all TLB management, so "lazy TLB" isn't very
37 * meaningful. Even for ports to architectures with visble TLBs,
38 * this is almost invariably a null function.
39 */
40static inline void enter_lazy_tlb(struct mm_struct *mm,
41 struct task_struct *tsk)
42{
43}
44
45/*
46 * Architecture-specific actions, if any, for memory map deactivation.
47 */
48static inline void deactivate_mm(struct task_struct *tsk,
49 struct mm_struct *mm)
50{
51}
52
53/**
54 * init_new_context - initialize context related info for new mm_struct instance
55 * @tsk: pointer to a task struct
56 * @mm: pointer to a new mm struct
57 */
58static inline int init_new_context(struct task_struct *tsk,
59 struct mm_struct *mm)
60{
61 /* mm->context is set up by pgd_alloc */
62 return 0;
63}
64
65/*
66 * Switch active mm context
67 */
68static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
69 struct task_struct *tsk)
70{
71 int l1;
72
73 /*
74 * For virtual machine, we have to update system map if it's been
75 * touched.
76 */
77 if (next->context.generation < prev->context.generation) {
78 for (l1 = MIN_KERNEL_SEG; l1 <= max_kernel_seg; l1++)
79 next->pgd[l1] = init_mm.pgd[l1];
80
81 next->context.generation = prev->context.generation;
82 }
83
84 __vmnewmap((void *)next->context.ptbase);
85}
86
87/*
88 * Activate new memory map for task
89 */
90static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
91{
92 unsigned long flags;
93
94 local_irq_save(flags);
95 switch_mm(prev, next, current_thread_info()->task);
96 local_irq_restore(flags);
97}
98
99/* Generic hooks for arch_dup_mmap and arch_exit_mmap */
100#include <asm-generic/mm_hooks.h>
101
102#endif