1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_IOBITMAP_H
3#define _ASM_X86_IOBITMAP_H
4
5#include <linux/refcount.h>
6#include <asm/processor.h>
7
8struct io_bitmap {
9 u64 sequence;
10 refcount_t refcnt;
11 /* The maximum number of bytes to copy so all zero bits are covered */
12 unsigned int max;
13 unsigned long bitmap[IO_BITMAP_LONGS];
14};
15
16struct task_struct;
17
18#ifdef CONFIG_X86_IOPL_IOPERM
19void io_bitmap_share(struct task_struct *tsk);
20void io_bitmap_exit(struct task_struct *tsk);
21
22static inline void native_tss_invalidate_io_bitmap(void)
23{
24 /*
25 * Invalidate the I/O bitmap by moving io_bitmap_base outside the
26 * TSS limit so any subsequent I/O access from user space will
27 * trigger a #GP.
28 *
29 * This is correct even when VMEXIT rewrites the TSS limit
30 * to 0x67 as the only requirement is that the base points
31 * outside the limit.
32 */
33 this_cpu_write(cpu_tss_rw.x86_tss.io_bitmap_base,
34 IO_BITMAP_OFFSET_INVALID);
35}
36
37void native_tss_update_io_bitmap(void);
38
39#ifdef CONFIG_PARAVIRT_XXL
40#include <asm/paravirt.h>
41#else
42#define tss_update_io_bitmap native_tss_update_io_bitmap
43#define tss_invalidate_io_bitmap native_tss_invalidate_io_bitmap
44#endif
45
46#else
47static inline void io_bitmap_share(struct task_struct *tsk) { }
48static inline void io_bitmap_exit(struct task_struct *tsk) { }
49static inline void tss_update_io_bitmap(void) { }
50#endif
51
52#endif
53