WSL2-Linux-Kernel/arch/arm/kernel/machine_kexec.c

141 строка
3.5 KiB
C

/*
* machine_kexec.c - handle transition of Linux booting another kernel
*/
#include <linux/mm.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
#include <asm/mach-types.h>
#include <asm/system_misc.h>
extern const unsigned char relocate_new_kernel[];
extern const unsigned int relocate_new_kernel_size;
extern unsigned long kexec_start_address;
extern unsigned long kexec_indirection_page;
extern unsigned long kexec_mach_type;
extern unsigned long kexec_boot_atags;
static atomic_t waiting_for_crash_ipi;
/*
* Provide a dummy crash_notes definition while crash dump arrives to arm.
* This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
*/
int machine_kexec_prepare(struct kimage *image)
{
return 0;
}
void machine_kexec_cleanup(struct kimage *image)
{
}
void machine_crash_nonpanic_core(void *unused)
{
struct pt_regs regs;
crash_setup_regs(&regs, NULL);
printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
smp_processor_id());
crash_save_cpu(&regs, smp_processor_id());
flush_cache_all();
atomic_dec(&waiting_for_crash_ipi);
while (1)
cpu_relax();
}
static void machine_kexec_mask_interrupts(void)
{
unsigned int i;
struct irq_desc *desc;
for_each_irq_desc(i, desc) {
struct irq_chip *chip;
chip = irq_desc_get_chip(desc);
if (!chip)
continue;
if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
chip->irq_eoi(&desc->irq_data);
if (chip->irq_mask)
chip->irq_mask(&desc->irq_data);
if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
chip->irq_disable(&desc->irq_data);
}
}
void machine_crash_shutdown(struct pt_regs *regs)
{
unsigned long msecs;
local_irq_disable();
atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
smp_call_function(machine_crash_nonpanic_core, NULL, false);
msecs = 1000; /* Wait at most a second for the other cpus to stop */
while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
mdelay(1);
msecs--;
}
if (atomic_read(&waiting_for_crash_ipi) > 0)
printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
crash_save_cpu(regs, smp_processor_id());
machine_kexec_mask_interrupts();
printk(KERN_INFO "Loading crashdump kernel...\n");
}
/*
* Function pointer to optional machine-specific reinitialization
*/
void (*kexec_reinit)(void);
void machine_kexec(struct kimage *image)
{
unsigned long page_list;
unsigned long reboot_code_buffer_phys;
void *reboot_code_buffer;
page_list = image->head & PAGE_MASK;
/* we need both effective and real address here */
reboot_code_buffer_phys =
page_to_pfn(image->control_code_page) << PAGE_SHIFT;
reboot_code_buffer = page_address(image->control_code_page);
/* Prepare parameters for reboot_code_buffer*/
kexec_start_address = image->start;
kexec_indirection_page = page_list;
kexec_mach_type = machine_arch_type;
kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
/* copy our kernel relocation code to the control code page */
memcpy(reboot_code_buffer,
relocate_new_kernel, relocate_new_kernel_size);
flush_icache_range((unsigned long) reboot_code_buffer,
(unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
printk(KERN_INFO "Bye!\n");
if (kexec_reinit)
kexec_reinit();
soft_restart(reboot_code_buffer_phys);
}