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-rw-r--r--include/asm-x86/xsave.h118
1 files changed, 118 insertions, 0 deletions
diff --git a/include/asm-x86/xsave.h b/include/asm-x86/xsave.h
new file mode 100644
index 000000000000..08e9a1ac07a9
--- /dev/null
+++ b/include/asm-x86/xsave.h
@@ -0,0 +1,118 @@
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
11#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
12
13#define FXSAVE_SIZE 512
14
15/*
16 * These are the features that the OS can handle currently.
17 */
18#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE)
19
20#ifdef CONFIG_X86_64
21#define REX_PREFIX "0x48, "
22#else
23#define REX_PREFIX
24#endif
25
26extern unsigned int xstate_size;
27extern u64 pcntxt_mask;
28extern struct xsave_struct *init_xstate_buf;
29
30extern void xsave_cntxt_init(void);
31extern void xsave_init(void);
32extern int init_fpu(struct task_struct *child);
33extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
34 void __user *fpstate,
35 struct _fpx_sw_bytes *sw);
36
37static inline int xrstor_checking(struct xsave_struct *fx)
38{
39 int err;
40
41 asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
42 "2:\n"
43 ".section .fixup,\"ax\"\n"
44 "3: movl $-1,%[err]\n"
45 " jmp 2b\n"
46 ".previous\n"
47 _ASM_EXTABLE(1b, 3b)
48 : [err] "=r" (err)
49 : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
50 : "memory");
51
52 return err;
53}
54
55static inline int xsave_user(struct xsave_struct __user *buf)
56{
57 int err;
58 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
59 "2:\n"
60 ".section .fixup,\"ax\"\n"
61 "3: movl $-1,%[err]\n"
62 " jmp 2b\n"
63 ".previous\n"
64 ".section __ex_table,\"a\"\n"
65 _ASM_ALIGN "\n"
66 _ASM_PTR "1b,3b\n"
67 ".previous"
68 : [err] "=r" (err)
69 : "D" (buf), "a" (-1), "d" (-1), "0" (0)
70 : "memory");
71 if (unlikely(err) && __clear_user(buf, xstate_size))
72 err = -EFAULT;
73 /* No need to clear here because the caller clears USED_MATH */
74 return err;
75}
76
77static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
78{
79 int err;
80 struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
81 u32 lmask = mask;
82 u32 hmask = mask >> 32;
83
84 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
85 "2:\n"
86 ".section .fixup,\"ax\"\n"
87 "3: movl $-1,%[err]\n"
88 " jmp 2b\n"
89 ".previous\n"
90 ".section __ex_table,\"a\"\n"
91 _ASM_ALIGN "\n"
92 _ASM_PTR "1b,3b\n"
93 ".previous"
94 : [err] "=r" (err)
95 : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
96 : "memory"); /* memory required? */
97 return err;
98}
99
100static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
101{
102 u32 lmask = mask;
103 u32 hmask = mask >> 32;
104
105 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
106 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
107 : "memory");
108}
109
110static inline void xsave(struct task_struct *tsk)
111{
112 /* This, however, we can work around by forcing the compiler to select
113 an addressing mode that doesn't require extended registers. */
114 __asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27"
115 : : "D" (&(tsk->thread.xstate->xsave)),
116 "a" (-1), "d"(-1) : "memory");
117}
118#endif