diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 70ca24853ef0..ae6fc12fd64f 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -5,8 +5,49 @@ */ #include +#include +#include #include +struct idt_data { + unsigned int vector; + unsigned int segment; + struct idt_bits bits; + const void *addr; +}; + +#define DPL0 0x0 +#define DPL3 0x3 + +#define DEFAULT_STACK 0 + +#define G(_vector, _addr, _ist, _type, _dpl, _segment) \ + { \ + .vector = _vector, \ + .bits.ist = _ist, \ + .bits.type = _type, \ + .bits.dpl = _dpl, \ + .bits.p = 1, \ + .addr = _addr, \ + .segment = _segment, \ + } + +/* Interrupt gate */ +#define INTG(_vector, _addr) \ + G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL0, __KERNEL_CS) + +/* System interrupt gate */ +#define SYSG(_vector, _addr) \ + G(_vector, _addr, DEFAULT_STACK, GATE_INTERRUPT, DPL3, __KERNEL_CS) + +/* Interrupt gate with interrupt stack */ +#define ISTG(_vector, _addr, _ist) \ + G(_vector, _addr, _ist, GATE_INTERRUPT, DPL0, __KERNEL_CS) + +/* Task gate */ +#define TSKG(_vector, _gdt) \ + G(_vector, NULL, DEFAULT_STACK, GATE_TASK, DPL0, _gdt << 3) + /* Must be page-aligned because the real IDT is used in a fixmap. */ gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss; @@ -25,6 +66,32 @@ const struct desc_ptr debug_idt_descr = { }; #endif +static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d) +{ + unsigned long addr = (unsigned long) d->addr; + + gate->offset_low = (u16) addr; + gate->segment = (u16) d->segment; + gate->bits = d->bits; + gate->offset_middle = (u16) (addr >> 16); +#ifdef CONFIG_X86_64 + gate->offset_high = (u32) (addr >> 32); + gate->reserved = 0; +#endif +} + +static __init void +idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size) +{ + gate_desc desc; + + for (; size > 0; t++, size--) { + idt_init_desc(&desc, t); + set_bit(t->vector, used_vectors); + write_idt_entry(idt, t->vector, &desc); + } +} + /** * idt_setup_early_handler - Initializes the idt table with early handlers */