arch/mips/kernel/smp.c - LeafOS-Devices/android_kernel_realme_mt6785 - Gitiles

 /*
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version 2
  * of the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  *
  * Copyright (C) 2000, 2001 Kanoj Sarcar
  * Copyright (C) 2000, 2001 Ralf Baechle
  * Copyright (C) 2000, 2001 Silicon Graphics, Inc.
  * Copyright (C) 2000, 2001, 2003 Broadcom Corporation
  */
 #include <linux/cache.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/smp.h>
 #include <linux/spinlock.h>
 #include <linux/threads.h>
 #include <linux/module.h>
 #include <linux/time.h>
 #include <linux/timex.h>
 #include <linux/sched.h>
 #include <linux/cpumask.h>
 #include <linux/cpu.h>
 #include <linux/err.h>
 #include <linux/ftrace.h>

 #include <linux/atomic.h>
 #include <asm/cpu.h>
 #include <asm/processor.h>
 #include <asm/r4k-timer.h>
 #include <asm/mmu_context.h>
 #include <asm/time.h>
 #include <asm/setup.h>

 #ifdef CONFIG_MIPS_MT_SMTC
 #include <asm/mipsmtregs.h>
 #endif /* CONFIG_MIPS_MT_SMTC */

 volatile cpumask_t cpu_callin_map;	/* Bitmask of started secondaries */

 int __cpu_number_map[NR_CPUS];		/* Map physical to logical */
 EXPORT_SYMBOL(__cpu_number_map);

 int __cpu_logical_map[NR_CPUS];		/* Map logical to physical */
 EXPORT_SYMBOL(__cpu_logical_map);

 /* Number of TCs (or siblings in Intel speak) per CPU core */
 int smp_num_siblings = 1;
 EXPORT_SYMBOL(smp_num_siblings);

 /* representing the TCs (or siblings in Intel speak) of each logical CPU */
 cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
 EXPORT_SYMBOL(cpu_sibling_map);

 /* representing cpus for which sibling maps can be computed */
 static cpumask_t cpu_sibling_setup_map;

 static inline void set_cpu_sibling_map(int cpu)
 {
 	int i;

 	cpu_set(cpu, cpu_sibling_setup_map);

 	if (smp_num_siblings > 1) {
 		for_each_cpu_mask(i, cpu_sibling_setup_map) {
 			if (cpu_data[cpu].core == cpu_data[i].core) {
 				cpu_set(i, cpu_sibling_map[cpu]);
 				cpu_set(cpu, cpu_sibling_map[i]);
 			}
 		}
 	} else
 		cpu_set(cpu, cpu_sibling_map[cpu]);
 }

 struct plat_smp_ops *mp_ops;

 __cpuinit void register_smp_ops(struct plat_smp_ops *ops)
 {
 	if (mp_ops)
 		printk(KERN_WARNING "Overriding previously set SMP ops\n");

 	mp_ops = ops;
 }

 /*
  * First C code run on the secondary CPUs after being started up by
  * the master.
  */
 asmlinkage __cpuinit void start_secondary(void)
 {
 	unsigned int cpu;

 #ifdef CONFIG_MIPS_MT_SMTC
 	/* Only do cpu_probe for first TC of CPU */
 	if ((read_c0_tcbind() & TCBIND_CURTC) == 0)
 #endif /* CONFIG_MIPS_MT_SMTC */
 	cpu_probe();
 	cpu_report();
 	per_cpu_trap_init();
 	mips_clockevent_init();
 	mp_ops->init_secondary();

 	/*
 	 * XXX parity protection should be folded in here when it's converted
 	 * to an option instead of something based on .cputype
 	 */

 	calibrate_delay();
 	preempt_disable();
 	cpu = smp_processor_id();
 	cpu_data[cpu].udelay_val = loops_per_jiffy;

 	notify_cpu_starting(cpu);

 	mp_ops->smp_finish();
 	set_cpu_sibling_map(cpu);

 	cpu_set(cpu, cpu_callin_map);

 	synchronise_count_slave();

 	cpu_idle();
 }

 /*
  * Call into both interrupt handlers, as we share the IPI for them
  */
 void __irq_entry smp_call_function_interrupt(void)
 {
 	irq_enter();
 	generic_smp_call_function_single_interrupt();
 	generic_smp_call_function_interrupt();
 	irq_exit();
 }

 static void stop_this_cpu(void *dummy)
 {
 	/*
 	 * Remove this CPU:
 	 */
 	cpu_clear(smp_processor_id(), cpu_online_map);
 	for (;;) {
 		if (cpu_wait)
 			(*cpu_wait)();		/* Wait if available. */
 	}
 }

 void smp_send_stop(void)
 {
 	smp_call_function(stop_this_cpu, NULL, 0);
 }

 void __init smp_cpus_done(unsigned int max_cpus)
 {
 	mp_ops->cpus_done();
 	synchronise_count_master();
 }

 /* called from main before smp_init() */
 void __init smp_prepare_cpus(unsigned int max_cpus)
 {
 	init_new_context(current, &init_mm);
 	current_thread_info()->cpu = 0;
 	mp_ops->prepare_cpus(max_cpus);
 	set_cpu_sibling_map(0);
 #ifndef CONFIG_HOTPLUG_CPU
 	init_cpu_present(&cpu_possible_map);
 #endif
 }

 /* preload SMP state for boot cpu */
 void __devinit smp_prepare_boot_cpu(void)
 {
 	set_cpu_possible(0, true);
 	set_cpu_online(0, true);
 	cpu_set(0, cpu_callin_map);
 }

 /*
  * Called once for each "cpu_possible(cpu)".  Needs to spin up the cpu
  * and keep control until "cpu_online(cpu)" is set.  Note: cpu is
  * physical, not logical.
  */
 static struct task_struct *cpu_idle_thread[NR_CPUS];

 struct create_idle {
 	struct work_struct work;
 	struct task_struct *idle;
 	struct completion done;
 	int cpu;
 };

 static void __cpuinit do_fork_idle(struct work_struct *work)
 {
 	struct create_idle *c_idle =
 		container_of(work, struct create_idle, work);

 	c_idle->idle = fork_idle(c_idle->cpu);
 	complete(&c_idle->done);
 }

 int __cpuinit __cpu_up(unsigned int cpu)
 {
 	struct task_struct *idle;

 	/*
 	 * Processor goes to start_secondary(), sets online flag
 	 * The following code is purely to make sure
 	 * Linux can schedule processes on this slave.
 	 */
 	if (!cpu_idle_thread[cpu]) {
 		/*
 		 * Schedule work item to avoid forking user task
 		 * Ported from arch/x86/kernel/smpboot.c
 		 */
 		struct create_idle c_idle = {
 			.cpu    = cpu,
 			.done   = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
 		};

 		INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
 		schedule_work(&c_idle.work);
 		wait_for_completion(&c_idle.done);
 		idle = cpu_idle_thread[cpu] = c_idle.idle;

 		if (IS_ERR(idle))
 			panic(KERN_ERR "Fork failed for CPU %d", cpu);
 	} else {
 		idle = cpu_idle_thread[cpu];
 		init_idle(idle, cpu);
 	}

 	mp_ops->boot_secondary(cpu, idle);

 	/*
 	 * Trust is futile.  We should really have timeouts ...
 	 */
 	while (!cpu_isset(cpu, cpu_callin_map))
 		udelay(100);

 	cpu_set(cpu, cpu_online_map);

 	return 0;
 }

 /* Not really SMP stuff ... */
 int setup_profiling_timer(unsigned int multiplier)
 {
 	return 0;
 }

 static void flush_tlb_all_ipi(void *info)
 {
 	local_flush_tlb_all();
 }

 void flush_tlb_all(void)
 {
 	on_each_cpu(flush_tlb_all_ipi, NULL, 1);
 }

 static void flush_tlb_mm_ipi(void *mm)
 {
 	local_flush_tlb_mm((struct mm_struct *)mm);
 }

 /*
  * Special Variant of smp_call_function for use by TLB functions:
  *
  *  o No return value
  *  o collapses to normal function call on UP kernels
  *  o collapses to normal function call on systems with a single shared
  *    primary cache.
  *  o CONFIG_MIPS_MT_SMTC currently implies there is only one physical core.
  */
 static inline void smp_on_other_tlbs(void (*func) (void *info), void *info)
 {
 #ifndef CONFIG_MIPS_MT_SMTC
 	smp_call_function(func, info, 1);
 #endif
 }

 static inline void smp_on_each_tlb(void (*func) (void *info), void *info)
 {
 	preempt_disable();

 	smp_on_other_tlbs(func, info);
 	func(info);

 	preempt_enable();
 }

 /*
  * The following tlb flush calls are invoked when old translations are
  * being torn down, or pte attributes are changing. For single threaded
  * address spaces, a new context is obtained on the current cpu, and tlb
  * context on other cpus are invalidated to force a new context allocation
  * at switch_mm time, should the mm ever be used on other cpus. For
  * multithreaded address spaces, intercpu interrupts have to be sent.
  * Another case where intercpu interrupts are required is when the target
  * mm might be active on another cpu (eg debuggers doing the flushes on
  * behalf of debugees, kswapd stealing pages from another process etc).
  * Kanoj 07/00.
  */

 void flush_tlb_mm(struct mm_struct *mm)
 {
 	preempt_disable();

 	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
 		smp_on_other_tlbs(flush_tlb_mm_ipi, mm);
 	} else {
 		cpumask_t mask = cpu_online_map;
 		unsigned int cpu;

 		cpu_clear(smp_processor_id(), mask);
 		for_each_cpu_mask(cpu, mask)
 			if (cpu_context(cpu, mm))
 				cpu_context(cpu, mm) = 0;
 	}
 	local_flush_tlb_mm(mm);

 	preempt_enable();
 }

 struct flush_tlb_data {
 	struct vm_area_struct *vma;
 	unsigned long addr1;
 	unsigned long addr2;
 };

 static void flush_tlb_range_ipi(void *info)
 {
 	struct flush_tlb_data *fd = info;

 	local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
 }

 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
 {
 	struct mm_struct *mm = vma->vm_mm;

 	preempt_disable();
 	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
 		struct flush_tlb_data fd = {
 			.vma = vma,
 			.addr1 = start,
 			.addr2 = end,
 		};

 		smp_on_other_tlbs(flush_tlb_range_ipi, &fd);
 	} else {
 		cpumask_t mask = cpu_online_map;
 		unsigned int cpu;

 		cpu_clear(smp_processor_id(), mask);
 		for_each_cpu_mask(cpu, mask)
 			if (cpu_context(cpu, mm))
 				cpu_context(cpu, mm) = 0;
 	}
 	local_flush_tlb_range(vma, start, end);
 	preempt_enable();
 }

 static void flush_tlb_kernel_range_ipi(void *info)
 {
 	struct flush_tlb_data *fd = info;

 	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
 }

 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 {
 	struct flush_tlb_data fd = {
 		.addr1 = start,
 		.addr2 = end,
 	};

 	on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1);
 }

 static void flush_tlb_page_ipi(void *info)
 {
 	struct flush_tlb_data *fd = info;

 	local_flush_tlb_page(fd->vma, fd->addr1);
 }

 void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
 {
 	preempt_disable();
 	if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) {
 		struct flush_tlb_data fd = {
 			.vma = vma,
 			.addr1 = page,
 		};

 		smp_on_other_tlbs(flush_tlb_page_ipi, &fd);
 	} else {
 		cpumask_t mask = cpu_online_map;
 		unsigned int cpu;

 		cpu_clear(smp_processor_id(), mask);
 		for_each_cpu_mask(cpu, mask)
 			if (cpu_context(cpu, vma->vm_mm))
 				cpu_context(cpu, vma->vm_mm) = 0;
 	}
 	local_flush_tlb_page(vma, page);
 	preempt_enable();
 }

 static void flush_tlb_one_ipi(void *info)
 {
 	unsigned long vaddr = (unsigned long) info;

 	local_flush_tlb_one(vaddr);
 }

 void flush_tlb_one(unsigned long vaddr)
 {
 	smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr);
 }

 EXPORT_SYMBOL(flush_tlb_page);
 EXPORT_SYMBOL(flush_tlb_one);
	/*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version 2
	* of the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	*
	* Copyright (C) 2000, 2001 Kanoj Sarcar
	* Copyright (C) 2000, 2001 Ralf Baechle
	* Copyright (C) 2000, 2001 Silicon Graphics, Inc.
	* Copyright (C) 2000, 2001, 2003 Broadcom Corporation
	*/
	#include <linux/cache.h>
	#include <linux/delay.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/smp.h>
	#include <linux/spinlock.h>
	#include <linux/threads.h>
	#include <linux/module.h>
	#include <linux/time.h>
	#include <linux/timex.h>
	#include <linux/sched.h>
	#include <linux/cpumask.h>
	#include <linux/cpu.h>
	#include <linux/err.h>
	#include <linux/ftrace.h>

	#include <linux/atomic.h>
	#include <asm/cpu.h>
	#include <asm/processor.h>
	#include <asm/r4k-timer.h>
	#include <asm/mmu_context.h>
	#include <asm/time.h>
	#include <asm/setup.h>

	#ifdef CONFIG_MIPS_MT_SMTC
	#include <asm/mipsmtregs.h>
	#endif /* CONFIG_MIPS_MT_SMTC */

	volatile cpumask_t cpu_callin_map; /* Bitmask of started secondaries */

	int __cpu_number_map[NR_CPUS]; /* Map physical to logical */
	EXPORT_SYMBOL(__cpu_number_map);

	int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */
	EXPORT_SYMBOL(__cpu_logical_map);

	/* Number of TCs (or siblings in Intel speak) per CPU core */
	int smp_num_siblings = 1;
	EXPORT_SYMBOL(smp_num_siblings);

	/* representing the TCs (or siblings in Intel speak) of each logical CPU */
	cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
	EXPORT_SYMBOL(cpu_sibling_map);

	/* representing cpus for which sibling maps can be computed */
	static cpumask_t cpu_sibling_setup_map;

	static inline void set_cpu_sibling_map(int cpu)
	{
	int i;

	cpu_set(cpu, cpu_sibling_setup_map);

	if (smp_num_siblings > 1) {
	for_each_cpu_mask(i, cpu_sibling_setup_map) {
	if (cpu_data[cpu].core == cpu_data[i].core) {
	cpu_set(i, cpu_sibling_map[cpu]);
	cpu_set(cpu, cpu_sibling_map[i]);
	}
	}
	} else
	cpu_set(cpu, cpu_sibling_map[cpu]);
	}

	struct plat_smp_ops *mp_ops;

	__cpuinit void register_smp_ops(struct plat_smp_ops *ops)
	{
	if (mp_ops)
	printk(KERN_WARNING "Overriding previously set SMP ops\n");

	mp_ops = ops;
	}

	/*
	* First C code run on the secondary CPUs after being started up by
	* the master.
	*/
	asmlinkage __cpuinit void start_secondary(void)
	{
	unsigned int cpu;

	#ifdef CONFIG_MIPS_MT_SMTC
	/* Only do cpu_probe for first TC of CPU */
	if ((read_c0_tcbind() & TCBIND_CURTC) == 0)
	#endif /* CONFIG_MIPS_MT_SMTC */
	cpu_probe();
	cpu_report();
	per_cpu_trap_init();
	mips_clockevent_init();
	mp_ops->init_secondary();

	/*
	* XXX parity protection should be folded in here when it's converted
	* to an option instead of something based on .cputype
	*/

	calibrate_delay();
	preempt_disable();
	cpu = smp_processor_id();
	cpu_data[cpu].udelay_val = loops_per_jiffy;

	notify_cpu_starting(cpu);

	mp_ops->smp_finish();
	set_cpu_sibling_map(cpu);

	cpu_set(cpu, cpu_callin_map);

	synchronise_count_slave();

	cpu_idle();
	}

	/*
	* Call into both interrupt handlers, as we share the IPI for them
	*/
	void __irq_entry smp_call_function_interrupt(void)
	{
	irq_enter();
	generic_smp_call_function_single_interrupt();
	generic_smp_call_function_interrupt();
	irq_exit();
	}

	static void stop_this_cpu(void *dummy)
	{
	/*
	* Remove this CPU:
	*/
	cpu_clear(smp_processor_id(), cpu_online_map);
	for (;;) {
	if (cpu_wait)
	(cpu_wait)(); / Wait if available. */
	}
	}

	void smp_send_stop(void)
	{
	smp_call_function(stop_this_cpu, NULL, 0);
	}

	void __init smp_cpus_done(unsigned int max_cpus)
	{
	mp_ops->cpus_done();
	synchronise_count_master();
	}

	/* called from main before smp_init() */
	void __init smp_prepare_cpus(unsigned int max_cpus)
	{
	init_new_context(current, &init_mm);
	current_thread_info()->cpu = 0;
	mp_ops->prepare_cpus(max_cpus);
	set_cpu_sibling_map(0);
	#ifndef CONFIG_HOTPLUG_CPU
	init_cpu_present(&cpu_possible_map);
	#endif
	}

	/* preload SMP state for boot cpu */
	void __devinit smp_prepare_boot_cpu(void)
	{
	set_cpu_possible(0, true);
	set_cpu_online(0, true);
	cpu_set(0, cpu_callin_map);
	}

	/*
	* Called once for each "cpu_possible(cpu)". Needs to spin up the cpu
	* and keep control until "cpu_online(cpu)" is set. Note: cpu is
	* physical, not logical.
	*/
	static struct task_struct *cpu_idle_thread[NR_CPUS];

	struct create_idle {
	struct work_struct work;
	struct task_struct *idle;
	struct completion done;
	int cpu;
	};

	static void __cpuinit do_fork_idle(struct work_struct *work)
	{
	struct create_idle *c_idle =
	container_of(work, struct create_idle, work);

	c_idle->idle = fork_idle(c_idle->cpu);
	complete(&c_idle->done);
	}

	int __cpuinit __cpu_up(unsigned int cpu)
	{
	struct task_struct *idle;

	/*
	* Processor goes to start_secondary(), sets online flag
	* The following code is purely to make sure
	* Linux can schedule processes on this slave.
	*/
	if (!cpu_idle_thread[cpu]) {
	/*
	* Schedule work item to avoid forking user task
	* Ported from arch/x86/kernel/smpboot.c
	*/
	struct create_idle c_idle = {
	.cpu = cpu,
	.done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
	};

	INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
	schedule_work(&c_idle.work);
	wait_for_completion(&c_idle.done);
	idle = cpu_idle_thread[cpu] = c_idle.idle;

	if (IS_ERR(idle))
	panic(KERN_ERR "Fork failed for CPU %d", cpu);
	} else {
	idle = cpu_idle_thread[cpu];
	init_idle(idle, cpu);
	}

	mp_ops->boot_secondary(cpu, idle);

	/*
	* Trust is futile. We should really have timeouts ...
	*/
	while (!cpu_isset(cpu, cpu_callin_map))
	udelay(100);

	cpu_set(cpu, cpu_online_map);

	return 0;
	}

	/* Not really SMP stuff ... */
	int setup_profiling_timer(unsigned int multiplier)
	{
	return 0;
	}

	static void flush_tlb_all_ipi(void *info)
	{
	local_flush_tlb_all();
	}

	void flush_tlb_all(void)
	{
	on_each_cpu(flush_tlb_all_ipi, NULL, 1);
	}

	static void flush_tlb_mm_ipi(void *mm)
	{
	local_flush_tlb_mm((struct mm_struct *)mm);
	}

	/*
	* Special Variant of smp_call_function for use by TLB functions:
	*
	* o No return value
	* o collapses to normal function call on UP kernels
	* o collapses to normal function call on systems with a single shared
	* primary cache.
	* o CONFIG_MIPS_MT_SMTC currently implies there is only one physical core.
	*/
	static inline void smp_on_other_tlbs(void (func) (void info), void *info)
	{
	#ifndef CONFIG_MIPS_MT_SMTC
	smp_call_function(func, info, 1);
	#endif
	}

	static inline void smp_on_each_tlb(void (func) (void info), void *info)
	{
	preempt_disable();

	smp_on_other_tlbs(func, info);
	func(info);

	preempt_enable();
	}

	/*
	* The following tlb flush calls are invoked when old translations are
	* being torn down, or pte attributes are changing. For single threaded
	* address spaces, a new context is obtained on the current cpu, and tlb
	* context on other cpus are invalidated to force a new context allocation
	* at switch_mm time, should the mm ever be used on other cpus. For
	* multithreaded address spaces, intercpu interrupts have to be sent.
	* Another case where intercpu interrupts are required is when the target
	* mm might be active on another cpu (eg debuggers doing the flushes on
	* behalf of debugees, kswapd stealing pages from another process etc).
	* Kanoj 07/00.
	*/

	void flush_tlb_mm(struct mm_struct *mm)
	{
	preempt_disable();

	if ((atomic_read(&mm->mm_users) != 1) \|\| (current->mm != mm)) {
	smp_on_other_tlbs(flush_tlb_mm_ipi, mm);
	} else {
	cpumask_t mask = cpu_online_map;
	unsigned int cpu;

	cpu_clear(smp_processor_id(), mask);
	for_each_cpu_mask(cpu, mask)
	if (cpu_context(cpu, mm))
	cpu_context(cpu, mm) = 0;
	}
	local_flush_tlb_mm(mm);

	preempt_enable();
	}

	struct flush_tlb_data {
	struct vm_area_struct *vma;
	unsigned long addr1;
	unsigned long addr2;
	};

	static void flush_tlb_range_ipi(void *info)
	{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
	}

	void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
	{
	struct mm_struct *mm = vma->vm_mm;

	preempt_disable();
	if ((atomic_read(&mm->mm_users) != 1) \|\| (current->mm != mm)) {
	struct flush_tlb_data fd = {
	.vma = vma,
	.addr1 = start,
	.addr2 = end,
	};

	smp_on_other_tlbs(flush_tlb_range_ipi, &fd);
	} else {
	cpumask_t mask = cpu_online_map;
	unsigned int cpu;

	cpu_clear(smp_processor_id(), mask);
	for_each_cpu_mask(cpu, mask)
	if (cpu_context(cpu, mm))
	cpu_context(cpu, mm) = 0;
	}
	local_flush_tlb_range(vma, start, end);
	preempt_enable();
	}

	static void flush_tlb_kernel_range_ipi(void *info)
	{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
	}

	void flush_tlb_kernel_range(unsigned long start, unsigned long end)
	{
	struct flush_tlb_data fd = {
	.addr1 = start,
	.addr2 = end,
	};

	on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1);
	}

	static void flush_tlb_page_ipi(void *info)
	{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_page(fd->vma, fd->addr1);
	}

	void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
	{
	preempt_disable();
	if ((atomic_read(&vma->vm_mm->mm_users) != 1) \|\| (current->mm != vma->vm_mm)) {
	struct flush_tlb_data fd = {
	.vma = vma,
	.addr1 = page,
	};

	smp_on_other_tlbs(flush_tlb_page_ipi, &fd);
	} else {
	cpumask_t mask = cpu_online_map;
	unsigned int cpu;

	cpu_clear(smp_processor_id(), mask);
	for_each_cpu_mask(cpu, mask)
	if (cpu_context(cpu, vma->vm_mm))
	cpu_context(cpu, vma->vm_mm) = 0;
	}
	local_flush_tlb_page(vma, page);
	preempt_enable();
	}

	static void flush_tlb_one_ipi(void *info)
	{
	unsigned long vaddr = (unsigned long) info;

	local_flush_tlb_one(vaddr);
	}

	void flush_tlb_one(unsigned long vaddr)
	{
	smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr);
	}

	EXPORT_SYMBOL(flush_tlb_page);
	EXPORT_SYMBOL(flush_tlb_one);