diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/arm/mm/context.c')
| -rw-r--r-- | ANDROID_3.4.5/arch/arm/mm/context.c | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/ANDROID_3.4.5/arch/arm/mm/context.c b/ANDROID_3.4.5/arch/arm/mm/context.c deleted file mode 100644 index 806cc4f6..00000000 --- a/ANDROID_3.4.5/arch/arm/mm/context.c +++ /dev/null @@ -1,171 +0,0 @@ -/* - * linux/arch/arm/mm/context.c - * - * Copyright (C) 2002-2003 Deep Blue Solutions Ltd, all rights reserved. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include <linux/init.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/percpu.h> - -#include <asm/mmu_context.h> -#include <asm/tlbflush.h> - -static DEFINE_RAW_SPINLOCK(cpu_asid_lock); -unsigned int cpu_last_asid = ASID_FIRST_VERSION; - -#ifdef CONFIG_ARM_LPAE -void cpu_set_reserved_ttbr0(void) -{ - unsigned long ttbl = __pa(swapper_pg_dir); - unsigned long ttbh = 0; - - /* - * Set TTBR0 to swapper_pg_dir which contains only global entries. The - * ASID is set to 0. - */ - asm volatile( - " mcrr p15, 0, %0, %1, c2 @ set TTBR0\n" - : - : "r" (ttbl), "r" (ttbh)); - isb(); -} -#else -void cpu_set_reserved_ttbr0(void) -{ - u32 ttb; - /* Copy TTBR1 into TTBR0 */ - asm volatile( - " mrc p15, 0, %0, c2, c0, 1 @ read TTBR1\n" - " mcr p15, 0, %0, c2, c0, 0 @ set TTBR0\n" - : "=r" (ttb)); - isb(); -} -#endif - -/* - * We fork()ed a process, and we need a new context for the child - * to run in. - */ -void __init_new_context(struct task_struct *tsk, struct mm_struct *mm) -{ - mm->context.id = 0; - raw_spin_lock_init(&mm->context.id_lock); -} - -static void flush_context(void) -{ - cpu_set_reserved_ttbr0(); - local_flush_tlb_all(); - if (icache_is_vivt_asid_tagged()) { - __flush_icache_all(); - dsb(); - } -} - -#ifdef CONFIG_SMP - -static void set_mm_context(struct mm_struct *mm, unsigned int asid) -{ - unsigned long flags; - - /* - * Locking needed for multi-threaded applications where the - * same mm->context.id could be set from different CPUs during - * the broadcast. This function is also called via IPI so the - * mm->context.id_lock has to be IRQ-safe. - */ - raw_spin_lock_irqsave(&mm->context.id_lock, flags); - if (likely((mm->context.id ^ cpu_last_asid) >> ASID_BITS)) { - /* - * Old version of ASID found. Set the new one and - * reset mm_cpumask(mm). - */ - mm->context.id = asid; - cpumask_clear(mm_cpumask(mm)); - } - raw_spin_unlock_irqrestore(&mm->context.id_lock, flags); - - /* - * Set the mm_cpumask(mm) bit for the current CPU. - */ - cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm)); -} - -/* - * Reset the ASID on the current CPU. This function call is broadcast - * from the CPU handling the ASID rollover and holding cpu_asid_lock. - */ -static void reset_context(void *info) -{ - unsigned int asid; - unsigned int cpu = smp_processor_id(); - struct mm_struct *mm = current->active_mm; - - smp_rmb(); - asid = cpu_last_asid + cpu + 1; - - flush_context(); - set_mm_context(mm, asid); - - /* set the new ASID */ - cpu_switch_mm(mm->pgd, mm); -} - -#else - -static inline void set_mm_context(struct mm_struct *mm, unsigned int asid) -{ - mm->context.id = asid; - cpumask_copy(mm_cpumask(mm), cpumask_of(smp_processor_id())); -} - -#endif - -void __new_context(struct mm_struct *mm) -{ - unsigned int asid; - - raw_spin_lock(&cpu_asid_lock); -#ifdef CONFIG_SMP - /* - * Check the ASID again, in case the change was broadcast from - * another CPU before we acquired the lock. - */ - if (unlikely(((mm->context.id ^ cpu_last_asid) >> ASID_BITS) == 0)) { - cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm)); - raw_spin_unlock(&cpu_asid_lock); - return; - } -#endif - /* - * At this point, it is guaranteed that the current mm (with - * an old ASID) isn't active on any other CPU since the ASIDs - * are changed simultaneously via IPI. - */ - asid = ++cpu_last_asid; - if (asid == 0) - asid = cpu_last_asid = ASID_FIRST_VERSION; - - /* - * If we've used up all our ASIDs, we need - * to start a new version and flush the TLB. - */ - if (unlikely((asid & ~ASID_MASK) == 0)) { - asid = cpu_last_asid + smp_processor_id() + 1; - flush_context(); -#ifdef CONFIG_SMP - smp_wmb(); - smp_call_function(reset_context, NULL, 1); -#endif - cpu_last_asid += NR_CPUS; - } - - set_mm_context(mm, asid); - raw_spin_unlock(&cpu_asid_lock); -} |