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
destroy_context(struct mm_struct * mm)31 static 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 */
enter_lazy_tlb(struct mm_struct * mm,struct task_struct * tsk)40 static 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 */
deactivate_mm(struct task_struct * tsk,struct mm_struct * mm)48 static 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 */
init_new_context(struct task_struct * tsk,struct mm_struct * mm)58 static 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 */
switch_mm(struct mm_struct * prev,struct mm_struct * next,struct task_struct * tsk)68 static 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 */
activate_mm(struct mm_struct * prev,struct mm_struct * next)90 static 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
103