arch/m68k/include/asm/segment.h

   1 #ifndef _M68K_SEGMENT_H
   2 #define _M68K_SEGMENT_H
   3
   4 /* define constants */
   5 /* Address spaces (FC0-FC2) */
   6 #define USER_DATA     (1)
   7 #ifndef __USER_DS
   8 #define __USER_DS     (USER_DATA)
   9 #endif
  10 #define USER_PROGRAM  (2)
  11 #define SUPER_DATA    (5)
  12 #ifndef __KERNEL_DS
  13 #define __KERNEL_DS   (SUPER_DATA)
  14 #endif
  15 #define SUPER_PROGRAM (6)
  16 #define CPU_SPACE     (7)
  17
  18 #ifndef __ASSEMBLY__
  19
  20 typedef struct {
  21         unsigned long seg;
  22 } mm_segment_t;
  23
  24 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
  25 #define USER_DS         MAKE_MM_SEG(__USER_DS)
  26 #define KERNEL_DS       MAKE_MM_SEG(__KERNEL_DS)
  27
  28 /*
  29  * Get/set the SFC/DFC registers for MOVES instructions
  30  */
  31
  32 static inline mm_segment_t get_fs(void)
  33 {
  34 #ifdef CONFIG_MMU
  35         mm_segment_t _v;
  36         __asm__ ("movec %/dfc,%0":"=r" (_v.seg):);
  37
  38         return _v;
  39 #else
  40         return USER_DS;
  41 #endif
  42 }
  43
  44 static inline mm_segment_t get_ds(void)
  45 {
  46     /* return the supervisor data space code */
  47     return KERNEL_DS;
  48 }
  49
  50 static inline void set_fs(mm_segment_t val)
  51 {
  52 #ifdef CONFIG_MMU
  53         __asm__ __volatile__ ("movec %0,%/sfc\n\t"
  54                               "movec %0,%/dfc\n\t"
  55                               : /* no outputs */ : "r" (val.seg) : "memory");
  56 #endif
  57 }
  58
  59 #define segment_eq(a,b) ((a).seg == (b).seg)
  60
  61 #endif /* __ASSEMBLY__ */
  62
  63 #endif /* _M68K_SEGMENT_H */