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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1#ifndef __ASM_X86_XSAVE_H
2#define __ASM_X86_XSAVE_H
3
4#include <linux/types.h>
5#include <asm/processor.h>
6#include <asm/i387.h>
7
8#define XSTATE_FP 0x1
9#define XSTATE_SSE 0x2
10#define XSTATE_YMM 0x4
11
12#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
13
14#define FXSAVE_SIZE 512
15
16/*
17 * These are the features that the OS can handle currently.
18 */
19#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE | XSTATE_YMM)
20
21#ifdef CONFIG_X86_64
22#define REX_PREFIX "0x48, "
23#else
24#define REX_PREFIX
25#endif
26
27extern unsigned int xstate_size;
28extern u64 pcntxt_mask;
29extern struct xsave_struct *init_xstate_buf;
30
31extern void xsave_cntxt_init(void);
32extern void xsave_init(void);
33extern int init_fpu(struct task_struct *child);
34extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
35 void __user *fpstate,
36 struct _fpx_sw_bytes *sw);
37
38static inline int xrstor_checking(struct xsave_struct *fx)
39{
40 int err;
41
42 asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
43 "2:\n"
44 ".section .fixup,\"ax\"\n"
45 "3: movl $-1,%[err]\n"
46 " jmp 2b\n"
47 ".previous\n"
48 _ASM_EXTABLE(1b, 3b)
49 : [err] "=r" (err)
50 : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
51 : "memory");
52
53 return err;
54}
55
56static inline int xsave_user(struct xsave_struct __user *buf)
57{
58 int err;
59 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
60 "2:\n"
61 ".section .fixup,\"ax\"\n"
62 "3: movl $-1,%[err]\n"
63 " jmp 2b\n"
64 ".previous\n"
65 ".section __ex_table,\"a\"\n"
66 _ASM_ALIGN "\n"
67 _ASM_PTR "1b,3b\n"
68 ".previous"
69 : [err] "=r" (err)
70 : "D" (buf), "a" (-1), "d" (-1), "0" (0)
71 : "memory");
72 if (unlikely(err) && __clear_user(buf, xstate_size))
73 err = -EFAULT;
74 /* No need to clear here because the caller clears USED_MATH */
75 return err;
76}
77
78static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
79{
80 int err;
81 struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
82 u32 lmask = mask;
83 u32 hmask = mask >> 32;
84
85 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
86 "2:\n"
87 ".section .fixup,\"ax\"\n"
88 "3: movl $-1,%[err]\n"
89 " jmp 2b\n"
90 ".previous\n"
91 ".section __ex_table,\"a\"\n"
92 _ASM_ALIGN "\n"
93 _ASM_PTR "1b,3b\n"
94 ".previous"
95 : [err] "=r" (err)
96 : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
97 : "memory"); /* memory required? */
98 return err;
99}
100
101static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
102{
103 u32 lmask = mask;
104 u32 hmask = mask >> 32;
105
106 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
107 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
108 : "memory");
109}
110
111static inline void xsave(struct task_struct *tsk)
112{
113 /* This, however, we can work around by forcing the compiler to select
114 an addressing mode that doesn't require extended registers. */
115 __asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27"
116 : : "D" (&(tsk->thread.xstate->xsave)),
117 "a" (-1), "d"(-1) : "memory");
118}
119#endif