linuxdebug/arch/x86/include/asm/io_bitmap.h

53 lines
1.3 KiB
C
Raw Normal View History

2024-07-16 15:50:57 +02:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_IOBITMAP_H
#define _ASM_X86_IOBITMAP_H
#include <linux/refcount.h>
#include <asm/processor.h>
struct io_bitmap {
u64 sequence;
refcount_t refcnt;
/* The maximum number of bytes to copy so all zero bits are covered */
unsigned int max;
unsigned long bitmap[IO_BITMAP_LONGS];
};
struct task_struct;
#ifdef CONFIG_X86_IOPL_IOPERM
void io_bitmap_share(struct task_struct *tsk);
void io_bitmap_exit(struct task_struct *tsk);
static inline void native_tss_invalidate_io_bitmap(void)
{
/*
* Invalidate the I/O bitmap by moving io_bitmap_base outside the
* TSS limit so any subsequent I/O access from user space will
* trigger a #GP.
*
* This is correct even when VMEXIT rewrites the TSS limit
* to 0x67 as the only requirement is that the base points
* outside the limit.
*/
this_cpu_write(cpu_tss_rw.x86_tss.io_bitmap_base,
IO_BITMAP_OFFSET_INVALID);
}
void native_tss_update_io_bitmap(void);
#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#define tss_update_io_bitmap native_tss_update_io_bitmap
#define tss_invalidate_io_bitmap native_tss_invalidate_io_bitmap
#endif
#else
static inline void io_bitmap_share(struct task_struct *tsk) { }
static inline void io_bitmap_exit(struct task_struct *tsk) { }
static inline void tss_update_io_bitmap(void) { }
#endif
#endif