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
8 struct 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
16 struct task_struct;
17
18 #ifdef CONFIG_X86_IOPL_IOPERM
19 void io_bitmap_share(struct task_struct *tsk);
20 void io_bitmap_exit(struct task_struct *tsk);
21
22 static 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
37 void 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
47 static inline void io_bitmap_share(struct task_struct *tsk) { }
48 static inline void io_bitmap_exit(struct task_struct *tsk) { }
49 static inline void tss_update_io_bitmap(void) { }
50 #endif
51
52 #endif
53
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