// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Uniprocessor-only support functions.  The counterpart to kernel/smp.c
   */

  #include <linux/interrupt.h>

  #include <linux/kernel.h>

  #include <linux/export.h>

  #include <linux/smp.h>

  #include <linux/hypervisor.h>

  
  int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
  				int wait)
  {

  	unsigned long flags;

  	if (cpu != 0)
  		return -ENXIO;

  	local_irq_save(flags);
  	func(info);
  	local_irq_restore(flags);

  	return 0;
  }
  EXPORT_SYMBOL(smp_call_function_single);

  int smp_call_function_single_async(int cpu, call_single_data_t *csd)

  {
  	unsigned long flags;
  
  	local_irq_save(flags);
  	csd->func(csd->info);
  	local_irq_restore(flags);

  	return 0;

  }

  EXPORT_SYMBOL(smp_call_function_single_async);

  void on_each_cpu(smp_call_func_t func, void *info, int wait)

  {
  	unsigned long flags;
  
  	local_irq_save(flags);
  	func(info);
  	local_irq_restore(flags);

  }
  EXPORT_SYMBOL(on_each_cpu);

  /*
   * Note we still need to test the mask even for UP
   * because we actually can get an empty mask from
   * code that on SMP might call us without the local
   * CPU in the mask.
   */
  void on_each_cpu_mask(const struct cpumask *mask,
  		      smp_call_func_t func, void *info, bool wait)
  {
  	unsigned long flags;
  
  	if (cpumask_test_cpu(0, mask)) {
  		local_irq_save(flags);
  		func(info);
  		local_irq_restore(flags);
  	}
  }
  EXPORT_SYMBOL(on_each_cpu_mask);
  
  /*
   * Preemption is disabled here to make sure the cond_func is called under the
   * same condtions in UP and SMP.
   */

  void on_each_cpu_cond_mask(smp_cond_func_t cond_func, smp_call_func_t func,

  			   void *info, bool wait, const struct cpumask *mask)

  {
  	unsigned long flags;
  
  	preempt_disable();
  	if (cond_func(0, info)) {
  		local_irq_save(flags);
  		func(info);
  		local_irq_restore(flags);
  	}
  	preempt_enable();
  }

  EXPORT_SYMBOL(on_each_cpu_cond_mask);

  void on_each_cpu_cond(smp_cond_func_t cond_func, smp_call_func_t func,

  		      void *info, bool wait)

  {

  	on_each_cpu_cond_mask(cond_func, func, info, wait, NULL);

  }

  EXPORT_SYMBOL(on_each_cpu_cond);

  
  int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys)
  {
  	int ret;
  
  	if (cpu != 0)
  		return -ENXIO;
  
  	if (phys)
  		hypervisor_pin_vcpu(0);
  	ret = func(par);
  	if (phys)
  		hypervisor_pin_vcpu(-1);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(smp_call_on_cpu);