SAFE public projects git trees. - safe/jmp/linux-2.6/blob - include/asm-x86/xsave.h

   1 #ifndef __ASM_X86_XSAVE_H
   2 #define __ASM_X86_XSAVE_H
   3
   4 #include <asm/processor.h>
   5 #include <asm/i387.h>
   6
   7 #define XSTATE_FP       0x1
   8 #define XSTATE_SSE      0x2
   9
  10 #define XSTATE_FPSSE    (XSTATE_FP | XSTATE_SSE)
  11
  12 #define FXSAVE_SIZE     512
  13
  14 /*
  15  * These are the features that the OS can handle currently.
  16  */
  17 #define XCNTXT_LMASK    (XSTATE_FP | XSTATE_SSE)
  18 #define XCNTXT_HMASK    0x0
  19
  20 #ifdef CONFIG_X86_64
  21 #define REX_PREFIX      "0x48, "
  22 #else
  23 #define REX_PREFIX
  24 #endif
  25
  26 extern unsigned int xstate_size, pcntxt_hmask, pcntxt_lmask;
  27 extern struct xsave_struct *init_xstate_buf;
  28
  29 extern void xsave_cntxt_init(void);
  30 extern void xsave_init(void);
  31 extern int init_fpu(struct task_struct *child);
  32
  33 static inline int xrstor_checking(struct xsave_struct *fx)
  34 {
  35         int err;
  36
  37         asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
  38                      "2:\n"
  39                      ".section .fixup,\"ax\"\n"
  40                      "3:  movl $-1,%[err]\n"
  41                      "    jmp  2b\n"
  42                      ".previous\n"
  43                      _ASM_EXTABLE(1b, 3b)
  44                      : [err] "=r" (err)
  45                      : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
  46                      : "memory");
  47
  48         return err;
  49 }
  50
  51 static inline int xsave_check(struct xsave_struct __user *buf)
  52 {
  53         int err;
  54         __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
  55                              "2:\n"
  56                              ".section .fixup,\"ax\"\n"
  57                              "3:  movl $-1,%[err]\n"
  58                              "    jmp  2b\n"
  59                              ".previous\n"
  60                              ".section __ex_table,\"a\"\n"
  61                              _ASM_ALIGN "\n"
  62                              _ASM_PTR "1b,3b\n"
  63                              ".previous"
  64                              : [err] "=r" (err)
  65                              : "D" (buf), "a" (-1), "d" (-1), "0" (0)
  66                              : "memory");
  67         if (unlikely(err) && __clear_user(buf, xstate_size))
  68                 err = -EFAULT;
  69         /* No need to clear here because the caller clears USED_MATH */
  70         return err;
  71 }
  72
  73 static inline int xrestore_user(struct xsave_struct __user *buf,
  74                                 unsigned int lmask,
  75                                 unsigned int hmask)
  76 {
  77         int err;
  78         struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
  79
  80         __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
  81                              "2:\n"
  82                              ".section .fixup,\"ax\"\n"
  83                              "3:  movl $-1,%[err]\n"
  84                              "    jmp  2b\n"
  85                              ".previous\n"
  86                              ".section __ex_table,\"a\"\n"
  87                              _ASM_ALIGN "\n"
  88                              _ASM_PTR "1b,3b\n"
  89                              ".previous"
  90                              : [err] "=r" (err)
  91                              : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
  92                              : "memory");       /* memory required? */
  93         return err;
  94 }
  95
  96 static inline void xrstor_state(struct xsave_struct *fx, int lmask, int hmask)
  97 {
  98         asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
  99                      : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
 100                      :   "memory");
 101 }
 102
 103 static inline void xsave(struct task_struct *tsk)
 104 {
 105         /* This, however, we can work around by forcing the compiler to select
 106            an addressing mode that doesn't require extended registers. */
 107         __asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27"
 108                              : : "D" (&(tsk->thread.xstate->xsave)),
 109                                  "a" (-1), "d"(-1) : "memory");
 110 }
 111 #endif