arch/x86/include/asm/xsave.h

   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 #define XSTATE_BNDREGS          0x8
  13 #define XSTATE_BNDCSR           0x10
  14 #define XSTATE_OPMASK           0x20
  15 #define XSTATE_ZMM_Hi256        0x40
  16 #define XSTATE_Hi16_ZMM         0x80
  17
  18 #define XSTATE_FPSSE    (XSTATE_FP | XSTATE_SSE)
  19
  20 #define FXSAVE_SIZE     512
  21
  22 #define XSAVE_HDR_SIZE      64
  23 #define XSAVE_HDR_OFFSET    FXSAVE_SIZE
  24
  25 #define XSAVE_YMM_SIZE      256
  26 #define XSAVE_YMM_OFFSET    (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
  27
  28 /* Supported features which support lazy state saving */
  29 #define XSTATE_LAZY     (XSTATE_FP | XSTATE_SSE | XSTATE_YMM                  \
  30                         | XSTATE_OPMASK | XSTATE_ZMM_Hi256 | XSTATE_Hi16_ZMM)
  31
  32 /* Supported features which require eager state saving */
  33 #define XSTATE_EAGER    (XSTATE_BNDREGS | XSTATE_BNDCSR)
  34
  35 /* All currently supported features */
  36 #define XCNTXT_MASK     (XSTATE_LAZY | XSTATE_EAGER)
  37
  38 #ifdef CONFIG_X86_64
  39 #define REX_PREFIX      "0x48, "
  40 #else
  41 #define REX_PREFIX
  42 #endif
  43
  44 extern unsigned int xstate_size;
  45 extern u64 pcntxt_mask;
  46 extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
  47 extern struct xsave_struct *init_xstate_buf;
  48
  49 extern void xsave_init(void);
  50 extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
  51 extern int init_fpu(struct task_struct *child);
  52
  53 static inline int fpu_xrstor_checking(struct xsave_struct *fx)
  54 {
  55         int err;
  56
  57         asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
  58                      "2:\n"
  59                      ".section .fixup,\"ax\"\n"
  60                      "3:  movl $-1,%[err]\n"
  61                      "    jmp  2b\n"
  62                      ".previous\n"
  63                      _ASM_EXTABLE(1b, 3b)
  64                      : [err] "=r" (err)
  65                      : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
  66                      : "memory");
  67
  68         return err;
  69 }
  70
  71 static inline int xsave_user(struct xsave_struct __user *buf)
  72 {
  73         int err;
  74
  75         /*
  76          * Clear the xsave header first, so that reserved fields are
  77          * initialized to zero.
  78          */
  79         err = __clear_user(&buf->xsave_hdr, sizeof(buf->xsave_hdr));
  80         if (unlikely(err))
  81                 return -EFAULT;
  82
  83         __asm__ __volatile__(ASM_STAC "\n"
  84                              "1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
  85                              "2: " ASM_CLAC "\n"
  86                              ".section .fixup,\"ax\"\n"
  87                              "3:  movl $-1,%[err]\n"
  88                              "    jmp  2b\n"
  89                              ".previous\n"
  90                              _ASM_EXTABLE(1b,3b)
  91                              : [err] "=r" (err)
  92                              : "D" (buf), "a" (-1), "d" (-1), "0" (0)
  93                              : "memory");
  94         return err;
  95 }
  96
  97 static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
  98 {
  99         int err;
 100         struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
 101         u32 lmask = mask;
 102         u32 hmask = mask >> 32;
 103
 104         __asm__ __volatile__(ASM_STAC "\n"
 105                              "1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
 106                              "2: " ASM_CLAC "\n"
 107                              ".section .fixup,\"ax\"\n"
 108                              "3:  movl $-1,%[err]\n"
 109                              "    jmp  2b\n"
 110                              ".previous\n"
 111                              _ASM_EXTABLE(1b,3b)
 112                              : [err] "=r" (err)
 113                              : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
 114                              : "memory");       /* memory required? */
 115         return err;
 116 }
 117
 118 static inline void xrstor_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,0x2f\n\t"
 124                      : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
 125                      :   "memory");
 126 }
 127
 128 static inline void xsave_state(struct xsave_struct *fx, u64 mask)
 129 {
 130         u32 lmask = mask;
 131         u32 hmask = mask >> 32;
 132
 133         asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x27\n\t"
 134                      : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
 135                      :   "memory");
 136 }
 137
 138 static inline void fpu_xsave(struct fpu *fpu)
 139 {
 140         /* This, however, we can work around by forcing the compiler to select
 141            an addressing mode that doesn't require extended registers. */
 142         alternative_input(
 143                 ".byte " REX_PREFIX "0x0f,0xae,0x27",
 144                 ".byte " REX_PREFIX "0x0f,0xae,0x37",
 145                 X86_FEATURE_XSAVEOPT,
 146                 [fx] "D" (&fpu->state->xsave), "a" (-1), "d" (-1) :
 147                 "memory");
 148 }
 149 #endif