77 lines
2.0 KiB
C
77 lines
2.0 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
/*
|
||
|
|
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
|
||
|
|
*
|
||
|
|
* This file contains the lowest level x86_64-specific interrupt
|
||
|
|
* entry and irq statistics code. All the remaining irq logic is
|
||
|
|
* done by the generic kernel/irq/ code and in the
|
||
|
|
* x86_64-specific irq controller code. (e.g. i8259.c and
|
||
|
|
* io_apic.c.)
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/kernel_stat.h>
|
||
|
|
#include <linux/interrupt.h>
|
||
|
|
#include <linux/irq.h>
|
||
|
|
#include <linux/seq_file.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/ftrace.h>
|
||
|
|
#include <linux/uaccess.h>
|
||
|
|
#include <linux/smp.h>
|
||
|
|
#include <linux/sched/task_stack.h>
|
||
|
|
|
||
|
|
#include <asm/cpu_entry_area.h>
|
||
|
|
#include <asm/softirq_stack.h>
|
||
|
|
#include <asm/irq_stack.h>
|
||
|
|
#include <asm/io_apic.h>
|
||
|
|
#include <asm/apic.h>
|
||
|
|
|
||
|
|
DEFINE_PER_CPU_PAGE_ALIGNED(struct irq_stack, irq_stack_backing_store) __visible;
|
||
|
|
DECLARE_INIT_PER_CPU(irq_stack_backing_store);
|
||
|
|
|
||
|
|
#ifdef CONFIG_VMAP_STACK
|
||
|
|
/*
|
||
|
|
* VMAP the backing store with guard pages
|
||
|
|
*/
|
||
|
|
static int map_irq_stack(unsigned int cpu)
|
||
|
|
{
|
||
|
|
char *stack = (char *)per_cpu_ptr(&irq_stack_backing_store, cpu);
|
||
|
|
struct page *pages[IRQ_STACK_SIZE / PAGE_SIZE];
|
||
|
|
void *va;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
for (i = 0; i < IRQ_STACK_SIZE / PAGE_SIZE; i++) {
|
||
|
|
phys_addr_t pa = per_cpu_ptr_to_phys(stack + (i << PAGE_SHIFT));
|
||
|
|
|
||
|
|
pages[i] = pfn_to_page(pa >> PAGE_SHIFT);
|
||
|
|
}
|
||
|
|
|
||
|
|
va = vmap(pages, IRQ_STACK_SIZE / PAGE_SIZE, VM_MAP, PAGE_KERNEL);
|
||
|
|
if (!va)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
/* Store actual TOS to avoid adjustment in the hotpath */
|
||
|
|
per_cpu(hardirq_stack_ptr, cpu) = va + IRQ_STACK_SIZE - 8;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
/*
|
||
|
|
* If VMAP stacks are disabled due to KASAN, just use the per cpu
|
||
|
|
* backing store without guard pages.
|
||
|
|
*/
|
||
|
|
static int map_irq_stack(unsigned int cpu)
|
||
|
|
{
|
||
|
|
void *va = per_cpu_ptr(&irq_stack_backing_store, cpu);
|
||
|
|
|
||
|
|
/* Store actual TOS to avoid adjustment in the hotpath */
|
||
|
|
per_cpu(hardirq_stack_ptr, cpu) = va + IRQ_STACK_SIZE - 8;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
int irq_init_percpu_irqstack(unsigned int cpu)
|
||
|
|
{
|
||
|
|
if (per_cpu(hardirq_stack_ptr, cpu))
|
||
|
|
return 0;
|
||
|
|
return map_irq_stack(cpu);
|
||
|
|
}
|