1 #ifndef __ASM_X86_XSAVE_H
2 #define __ASM_X86_XSAVE_H
3
4 #include <linux/types.h>
5 #include <asm/processor.h>
6
7 #define XSTATE_CPUID 0x0000000d
8
9 #define XSTATE_FP 0x1
10 #define XSTATE_SSE 0x2
11 #define XSTATE_YMM 0x4
12
13 #define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
14
15 #define FXSAVE_SIZE 512
16
17 #define XSAVE_HDR_SIZE 64
18 #define XSAVE_HDR_OFFSET FXSAVE_SIZE
19
20 #define XSAVE_YMM_SIZE 256
21 #define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
22
23 /*
24 * These are the features that the OS can handle currently.
25 */
26 #define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE | XSTATE_YMM)
27
28 #ifdef CONFIG_X86_64
29 #define REX_PREFIX "0x48, "
30 #else
31 #define REX_PREFIX
32 #endif
33
34 extern unsigned int xstate_size;
35 extern u64 pcntxt_mask;
36 extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
37
38 extern void xsave_init(void);
39 extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
40 extern int init_fpu(struct task_struct *child);
41 extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
42 void __user *fpstate,
43 struct _fpx_sw_bytes *sw);
44
fpu_xrstor_checking(struct fpu * fpu)45 static inline int fpu_xrstor_checking(struct fpu *fpu)
46 {
47 struct xsave_struct *fx = &fpu->state->xsave;
48 int err;
49
50 asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
51 "2:\n"
52 ".section .fixup,\"ax\"\n"
53 "3: movl $-1,%[err]\n"
54 " jmp 2b\n"
55 ".previous\n"
56 _ASM_EXTABLE(1b, 3b)
57 : [err] "=r" (err)
58 : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
59 : "memory");
60
61 return err;
62 }
63
xsave_user(struct xsave_struct __user * buf)64 static inline int xsave_user(struct xsave_struct __user *buf)
65 {
66 int err;
67
68 /*
69 * Clear the xsave header first, so that reserved fields are
70 * initialized to zero.
71 */
72 err = __clear_user(&buf->xsave_hdr,
73 sizeof(struct xsave_hdr_struct));
74 if (unlikely(err))
75 return -EFAULT;
76
77 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
78 "2:\n"
79 ".section .fixup,\"ax\"\n"
80 "3: movl $-1,%[err]\n"
81 " jmp 2b\n"
82 ".previous\n"
83 ".section __ex_table,\"a\"\n"
84 _ASM_ALIGN "\n"
85 _ASM_PTR "1b,3b\n"
86 ".previous"
87 : [err] "=r" (err)
88 : "D" (buf), "a" (-1), "d" (-1), "0" (0)
89 : "memory");
90 if (unlikely(err) && __clear_user(buf, xstate_size))
91 err = -EFAULT;
92 /* No need to clear here because the caller clears USED_MATH */
93 return err;
94 }
95
xrestore_user(struct xsave_struct __user * buf,u64 mask)96 static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
97 {
98 int err;
99 struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
100 u32 lmask = mask;
101 u32 hmask = mask >> 32;
102
103 __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
104 "2:\n"
105 ".section .fixup,\"ax\"\n"
106 "3: movl $-1,%[err]\n"
107 " jmp 2b\n"
108 ".previous\n"
109 ".section __ex_table,\"a\"\n"
110 _ASM_ALIGN "\n"
111 _ASM_PTR "1b,3b\n"
112 ".previous"
113 : [err] "=r" (err)
114 : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
115 : "memory"); /* memory required? */
116 return err;
117 }
118
xrstor_state(struct xsave_struct * fx,u64 mask)119 static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
120 {
121 u32 lmask = mask;
122 u32 hmask = mask >> 32;
123
124 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
125 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
126 : "memory");
127 }
128
xsave_state(struct xsave_struct * fx,u64 mask)129 static inline void xsave_state(struct xsave_struct *fx, u64 mask)
130 {
131 u32 lmask = mask;
132 u32 hmask = mask >> 32;
133
134 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x27\n\t"
135 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
136 : "memory");
137 }
138
fpu_xsave(struct fpu * fpu)139 static inline void fpu_xsave(struct fpu *fpu)
140 {
141 /* This, however, we can work around by forcing the compiler to select
142 an addressing mode that doesn't require extended registers. */
143 alternative_input(
144 ".byte " REX_PREFIX "0x0f,0xae,0x27",
145 ".byte " REX_PREFIX "0x0f,0xae,0x37",
146 X86_FEATURE_XSAVEOPT,
147 [fx] "D" (&fpu->state->xsave), "a" (-1), "d" (-1) :
148 "memory");
149 }
150 #endif
151