Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Russell King | 4baa992 | 2008-08-02 10:55:55 +0100 | [diff] [blame] | 2 | * arch/arm/include/asm/mmu_context.h |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 1996 Russell King. |
| 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 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * Changelog: |
| 11 | * 27-06-1996 RMK Created |
| 12 | */ |
| 13 | #ifndef __ASM_ARM_MMU_CONTEXT_H |
| 14 | #define __ASM_ARM_MMU_CONTEXT_H |
| 15 | |
Russell King | 8dc39b8 | 2005-11-16 17:23:57 +0000 | [diff] [blame] | 16 | #include <linux/compiler.h> |
Russell King | 87c5257 | 2008-11-29 17:35:51 +0000 | [diff] [blame] | 17 | #include <linux/sched.h> |
Russell King | 4fe15ba | 2005-11-06 19:47:04 +0000 | [diff] [blame] | 18 | #include <asm/cacheflush.h> |
Russell King | 46097c7 | 2008-08-10 18:10:19 +0100 | [diff] [blame] | 19 | #include <asm/cachetype.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <asm/proc-fns.h> |
Will Deacon | 621a014 | 2013-06-12 12:25:56 +0100 | [diff] [blame] | 21 | #include <asm/smp_plat.h> |
Will Deacon | f9d4861 | 2012-01-20 12:01:13 +0100 | [diff] [blame] | 22 | #include <asm-generic/mm_hooks.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | |
Nicolas Pitre | 3e99675 | 2012-11-25 03:24:32 +0100 | [diff] [blame] | 24 | void __check_vmalloc_seq(struct mm_struct *mm); |
Russell King | ff0daca | 2006-06-29 20:17:15 +0100 | [diff] [blame] | 25 | |
Russell King | 516793c | 2007-05-17 10:19:23 +0100 | [diff] [blame] | 26 | #ifdef CONFIG_CPU_HAS_ASID |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
Will Deacon | b5466f8 | 2012-06-15 14:47:31 +0100 | [diff] [blame] | 28 | void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk); |
Will Deacon | 8a4e3a9 | 2013-02-28 17:47:36 +0100 | [diff] [blame] | 29 | #define init_new_context(tsk,mm) ({ atomic64_set(&mm->context.id, 0); 0; }) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Marc Zyngier | 0d0752b | 2013-06-21 12:07:27 +0100 | [diff] [blame] | 31 | #ifdef CONFIG_ARM_ERRATA_798181 |
| 32 | void a15_erratum_get_cpumask(int this_cpu, struct mm_struct *mm, |
| 33 | cpumask_t *mask); |
| 34 | #else /* !CONFIG_ARM_ERRATA_798181 */ |
| 35 | static inline void a15_erratum_get_cpumask(int this_cpu, struct mm_struct *mm, |
| 36 | cpumask_t *mask) |
| 37 | { |
| 38 | } |
| 39 | #endif /* CONFIG_ARM_ERRATA_798181 */ |
Catalin Marinas | 93dc688 | 2013-03-26 23:35:04 +0100 | [diff] [blame] | 40 | |
Catalin Marinas | 7fec1b5 | 2011-11-28 13:53:28 +0000 | [diff] [blame] | 41 | #else /* !CONFIG_CPU_HAS_ASID */ |
| 42 | |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 43 | #ifdef CONFIG_MMU |
| 44 | |
Catalin Marinas | 7fec1b5 | 2011-11-28 13:53:28 +0000 | [diff] [blame] | 45 | static inline void check_and_switch_context(struct mm_struct *mm, |
| 46 | struct task_struct *tsk) |
Russell King | ff0daca | 2006-06-29 20:17:15 +0100 | [diff] [blame] | 47 | { |
Nicolas Pitre | 3e99675 | 2012-11-25 03:24:32 +0100 | [diff] [blame] | 48 | if (unlikely(mm->context.vmalloc_seq != init_mm.context.vmalloc_seq)) |
| 49 | __check_vmalloc_seq(mm); |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 50 | |
| 51 | if (irqs_disabled()) |
| 52 | /* |
| 53 | * cpu_switch_mm() needs to flush the VIVT caches. To avoid |
| 54 | * high interrupt latencies, defer the call and continue |
| 55 | * running with the old mm. Since we only support UP systems |
| 56 | * on non-ASID CPUs, the old mm will remain valid until the |
| 57 | * finish_arch_post_lock_switch() call. |
| 58 | */ |
Catalin Marinas | bdae73c | 2013-07-23 16:15:36 +0100 | [diff] [blame] | 59 | mm->context.switch_pending = 1; |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 60 | else |
| 61 | cpu_switch_mm(mm->pgd, mm); |
Russell King | ff0daca | 2006-06-29 20:17:15 +0100 | [diff] [blame] | 62 | } |
| 63 | |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 64 | #define finish_arch_post_lock_switch \ |
| 65 | finish_arch_post_lock_switch |
| 66 | static inline void finish_arch_post_lock_switch(void) |
| 67 | { |
Catalin Marinas | bdae73c | 2013-07-23 16:15:36 +0100 | [diff] [blame] | 68 | struct mm_struct *mm = current->mm; |
| 69 | |
| 70 | if (mm && mm->context.switch_pending) { |
| 71 | /* |
| 72 | * Preemption must be disabled during cpu_switch_mm() as we |
| 73 | * have some stateful cache flush implementations. Check |
| 74 | * switch_pending again in case we were preempted and the |
| 75 | * switch to this mm was already done. |
| 76 | */ |
| 77 | preempt_disable(); |
| 78 | if (mm->context.switch_pending) { |
| 79 | mm->context.switch_pending = 0; |
| 80 | cpu_switch_mm(mm->pgd, mm); |
| 81 | } |
| 82 | preempt_enable_no_resched(); |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 83 | } |
| 84 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
Catalin Marinas | b9d4d42 | 2011-11-28 21:57:24 +0000 | [diff] [blame] | 86 | #endif /* CONFIG_MMU */ |
| 87 | |
| 88 | #define init_new_context(tsk,mm) 0 |
Catalin Marinas | 7fec1b5 | 2011-11-28 13:53:28 +0000 | [diff] [blame] | 89 | |
| 90 | #endif /* CONFIG_CPU_HAS_ASID */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
| 92 | #define destroy_context(mm) do { } while(0) |
Will Deacon | b5466f8 | 2012-06-15 14:47:31 +0100 | [diff] [blame] | 93 | #define activate_mm(prev,next) switch_mm(prev, next, NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | |
| 95 | /* |
| 96 | * This is called when "tsk" is about to enter lazy TLB mode. |
| 97 | * |
| 98 | * mm: describes the currently active mm context |
| 99 | * tsk: task which is entering lazy tlb |
| 100 | * cpu: cpu number which is entering lazy tlb |
| 101 | * |
| 102 | * tsk->mm will be NULL |
| 103 | */ |
| 104 | static inline void |
| 105 | enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) |
| 106 | { |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * This is the actual mm switch as far as the scheduler |
| 111 | * is concerned. No registers are touched. We avoid |
| 112 | * calling the CPU specific function when the mm hasn't |
| 113 | * actually changed. |
| 114 | */ |
| 115 | static inline void |
| 116 | switch_mm(struct mm_struct *prev, struct mm_struct *next, |
| 117 | struct task_struct *tsk) |
| 118 | { |
Russell King | 002547b | 2006-06-20 20:46:52 +0100 | [diff] [blame] | 119 | #ifdef CONFIG_MMU |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | unsigned int cpu = smp_processor_id(); |
| 121 | |
Will Deacon | 621a014 | 2013-06-12 12:25:56 +0100 | [diff] [blame] | 122 | /* |
| 123 | * __sync_icache_dcache doesn't broadcast the I-cache invalidation, |
| 124 | * so check for possible thread migration and invalidate the I-cache |
| 125 | * if we're new to this CPU. |
| 126 | */ |
| 127 | if (cache_ops_need_broadcast() && |
| 128 | !cpumask_empty(mm_cpumask(next)) && |
Rusty Russell | 56f8ba8 | 2009-09-24 09:34:49 -0600 | [diff] [blame] | 129 | !cpumask_test_cpu(cpu, mm_cpumask(next))) |
Catalin Marinas | 826cbda | 2008-06-13 10:28:36 +0100 | [diff] [blame] | 130 | __flush_icache_all(); |
Will Deacon | 621a014 | 2013-06-12 12:25:56 +0100 | [diff] [blame] | 131 | |
Rusty Russell | 56f8ba8 | 2009-09-24 09:34:49 -0600 | [diff] [blame] | 132 | if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) { |
Catalin Marinas | 7fec1b5 | 2011-11-28 13:53:28 +0000 | [diff] [blame] | 133 | check_and_switch_context(next, tsk); |
Russell King | 7e5e6e9 | 2005-11-03 20:32:45 +0000 | [diff] [blame] | 134 | if (cache_is_vivt()) |
Rusty Russell | 56f8ba8 | 2009-09-24 09:34:49 -0600 | [diff] [blame] | 135 | cpumask_clear_cpu(cpu, mm_cpumask(prev)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | } |
Russell King | 002547b | 2006-06-20 20:46:52 +0100 | [diff] [blame] | 137 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | } |
| 139 | |
| 140 | #define deactivate_mm(tsk,mm) do { } while (0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | #endif |