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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
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
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
34extern unsigned int xstate_size;
35extern u64 pcntxt_mask;
36extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
37extern struct xsave_struct *init_xstate_buf;
38
39extern void xsave_init(void);
40extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
41extern int init_fpu(struct task_struct *child);
42
43static inline int fpu_xrstor_checking(struct xsave_struct *fx)
44{
45 int err;
46
47 asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
48 "2:\n"
49 ".section .fixup,\"ax\"\n"
50 "3: movl $-1,%[err]\n"
51 " jmp 2b\n"
52 ".previous\n"
53 _ASM_EXTABLE(1b, 3b)
54 : [err] "=r" (err)
55 : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
56 : "memory");
57
58 return err;
59}
60
61static inline int xsave_user(struct xsave_struct __user *buf)
62{
63 int err;
64
65 /*
66 * Clear the xsave header first, so that reserved fields are
67 * initialized to zero.
68 */
69 err = __clear_user(&buf->xsave_hdr, sizeof(buf->xsave_hdr));
70 if (unlikely(err))
71 return -EFAULT;
72
73 __asm__ __volatile__(ASM_STAC "\n"
74 "1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
75 "2: " ASM_CLAC "\n"
76 ".section .fixup,\"ax\"\n"
77 "3: movl $-1,%[err]\n"
78 " jmp 2b\n"
79 ".previous\n"
80 _ASM_EXTABLE(1b,3b)
81 : [err] "=r" (err)
82 : "D" (buf), "a" (-1), "d" (-1), "0" (0)
83 : "memory");
84 return err;
85}
86
87static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
88{
89 int err;
90 struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
91 u32 lmask = mask;
92 u32 hmask = mask >> 32;
93
94 __asm__ __volatile__(ASM_STAC "\n"
95 "1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
96 "2: " ASM_CLAC "\n"
97 ".section .fixup,\"ax\"\n"
98 "3: movl $-1,%[err]\n"
99 " jmp 2b\n"
100 ".previous\n"
101 _ASM_EXTABLE(1b,3b)
102 : [err] "=r" (err)
103 : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
104 : "memory"); /* memory required? */
105 return err;
106}
107
108static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
109{
110 u32 lmask = mask;
111 u32 hmask = mask >> 32;
112
113 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
114 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
115 : "memory");
116}
117
118static inline void xsave_state(struct xsave_struct *fx, u64 mask)
119{
120 u32 lmask = mask;
121 u32 hmask = mask >> 32;
122
123 asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x27\n\t"
124 : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
125 : "memory");
126}
127
128static inline void fpu_xsave(struct fpu *fpu)
129{
130 /* This, however, we can work around by forcing the compiler to select
131 an addressing mode that doesn't require extended registers. */
132 alternative_input(
133 ".byte " REX_PREFIX "0x0f,0xae,0x27",
134 ".byte " REX_PREFIX "0x0f,0xae,0x37",
135 X86_FEATURE_XSAVEOPT,
136 [fx] "D" (&fpu->state->xsave), "a" (-1), "d" (-1) :
137 "memory");
138}
139#endif