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

 1/* SPDX-License-Identifier: GPL-2.0-only */
 2/*
 3 * MM context support for the Hexagon architecture
 4 *
 5 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 6 */
 7
 8#ifndef _ASM_MMU_CONTEXT_H
 9#define _ASM_MMU_CONTEXT_H
10
11#include <linux/mm_types.h>
12
13#include <asm/setup.h>
14#include <asm/page.h>
15#include <asm/pgalloc.h>
16#include <asm/mem-layout.h>
17
18static inline void destroy_context(struct mm_struct *mm)
19{
20}
21
22/*
23 * VM port hides all TLB management, so "lazy TLB" isn't very
24 * meaningful.  Even for ports to architectures with visble TLBs,
25 * this is almost invariably a null function.
26 */
27static inline void enter_lazy_tlb(struct mm_struct *mm,
28	struct task_struct *tsk)
29{
30}
31
32/*
33 * Architecture-specific actions, if any, for memory map deactivation.
34 */
35static inline void deactivate_mm(struct task_struct *tsk,
36	struct mm_struct *mm)
37{
38}
39
40/**
41 * init_new_context - initialize context related info for new mm_struct instance
42 * @tsk: pointer to a task struct
43 * @mm: pointer to a new mm struct
44 */
45static inline int init_new_context(struct task_struct *tsk,
46					struct mm_struct *mm)
47{
48	/* mm->context is set up by pgd_alloc */
49	return 0;
50}
51
52/*
53 *  Switch active mm context
54 */
55static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
56				struct task_struct *tsk)
57{
58	int l1;
59
60	/*
61	 * For virtual machine, we have to update system map if it's been
62	 * touched.
63	 */
64	if (next->context.generation < prev->context.generation) {
65		for (l1 = MIN_KERNEL_SEG; l1 <= max_kernel_seg; l1++)
66			next->pgd[l1] = init_mm.pgd[l1];
67
68		next->context.generation = prev->context.generation;
69	}
70
71	__vmnewmap((void *)next->context.ptbase);
72}
73
74/*
75 *  Activate new memory map for task
76 */
77static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
78{
79	unsigned long flags;
80
81	local_irq_save(flags);
82	switch_mm(prev, next, current_thread_info()->task);
83	local_irq_restore(flags);
84}
85
86/*  Generic hooks for arch_dup_mmap and arch_exit_mmap  */
87#include <asm-generic/mm_hooks.h>
88
89#endif