android_kernel_xiaomi_sm8350/arch/arm/mm/context.c
Rusty Russell 56f8ba83a5 cpumask: use mm_cpumask() wrapper: arm
Makes code futureproof against the impending change to mm->cpu_vm_mask.

It's also a chance to use the new cpumask_ ops which take a pointer
(the older ones are deprecated, but there's no hurry for arch code).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-24 09:34:49 +09:30

65 lines
1.6 KiB
C

/*
* 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 <asm/mmu_context.h>
#include <asm/tlbflush.h>
static DEFINE_SPINLOCK(cpu_asid_lock);
unsigned int cpu_last_asid = ASID_FIRST_VERSION;
/*
* We fork()ed a process, and we need a new context for the child
* to run in. We reserve version 0 for initial tasks so we will
* always allocate an ASID. The ASID 0 is reserved for the TTBR
* register changing sequence.
*/
void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
mm->context.id = 0;
}
void __new_context(struct mm_struct *mm)
{
unsigned int asid;
spin_lock(&cpu_asid_lock);
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;
/* set the reserved ASID before flushing the TLB */
asm("mcr p15, 0, %0, c13, c0, 1 @ set reserved context ID\n"
:
: "r" (0));
isb();
flush_tlb_all();
if (icache_is_vivt_asid_tagged()) {
asm("mcr p15, 0, %0, c7, c5, 0 @ invalidate I-cache\n"
"mcr p15, 0, %0, c7, c5, 6 @ flush BTAC/BTB\n"
:
: "r" (0));
dsb();
}
}
spin_unlock(&cpu_asid_lock);
cpumask_copy(mm_cpumask(mm), cpumask_of(smp_processor_id()));
mm->context.id = asid;
}