arch/x86/boot/io.h

Source file repositories/reference/linux-study-clean/arch/x86/boot/io.h

File Facts

System
Linux kernel
Corpus path
arch/x86/boot/io.h
Extension
.h
Size
774 bytes
Lines
42
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct port_io_ops {
	u8	(*f_inb)(u16 port);
	void	(*f_outb)(u8 v, u16 port);
	void	(*f_outw)(u16 v, u16 port);
};

extern struct port_io_ops pio_ops;

/*
 * Use the normal I/O instructions by default.
 * TDX guests override these to use hypercalls.
 */
static inline void init_default_io_ops(void)
{
	pio_ops.f_inb  = __inb;
	pio_ops.f_outb = __outb;
	pio_ops.f_outw = __outw;
}

/*
 * Redirect port I/O operations via pio_ops callbacks.
 * TDX guests override these callbacks with TDX-specific helpers.
 */
#define inb  pio_ops.f_inb
#define outb pio_ops.f_outb
#define outw pio_ops.f_outw

#endif

Annotation

Implementation Notes