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#include "gdt.h"
gdt_entry gdt[] = {
gdt_entry_init(0, 0, 0),
gdt_entry_init(0, 0xfffff, 0xc09a), // Code segment.
gdt_entry_init(0, 0xfffff, 0xc092), // Data segment.
gdt_entry_init(0, 0xfffff, 0xc0fa), // User mode code segment.
gdt_entry_init(0, 0xfffff, 0xc0f2), // User mode data segment.
};
gdt_ptr gdtr = {
.base = gdt,
.limit = sizeof(gdt) - 1
};
void gdt_init() {
asm volatile(
"lgdt (%0)\n"
"mov %w1, %%ds\n"
"mov %w1, %%es\n"
"mov %w1, %%fs\n"
"mov %w1, %%gs\n"
"mov %w1, %%ss\n"
"ljmp $0x08, $.flush\n"
".flush:\n"
: : "r" (&gdtr), "r" (0x10)
);
}
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