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
  26 #ifdef CONFIG_CPU_HAS_ADDRESS_SPACES
  27 /*
  28  * Get/set the SFC/DFC registers for MOVES instructions
  29  */
  30 #define USER_DS         MAKE_MM_SEG(__USER_DS)
  31 #define KERNEL_DS       MAKE_MM_SEG(__KERNEL_DS)
  32
  33 static inline mm_segment_t get_fs(void)
  34 {
  35         mm_segment_t _v;
  36         __asm__ ("movec %/dfc,%0":"=r" (_v.seg):);
  37         return _v;
  38 }
  39
  40 static inline void set_fs(mm_segment_t val)
  41 {
  42         __asm__ __volatile__ ("movec %0,%/sfc\n\t"
  43                               "movec %0,%/dfc\n\t"
  44                               : /* no outputs */ : "r" (val.seg) : "memory");
  45 }
  46
  47 static inline mm_segment_t get_ds(void)
  48 {
  49     /* return the supervisor data space code */
  50     return KERNEL_DS;
  51 }
  52
  53 #else
  54 #define USER_DS         MAKE_MM_SEG(TASK_SIZE)
  55 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
  56 #define get_ds()        (KERNEL_DS)
  57 #define get_fs()        (current_thread_info()->addr_limit)
  58 #define set_fs(x)       (current_thread_info()->addr_limit = (x))
  59 #endif
  60
  61 #define segment_eq(a, b) ((a).seg == (b).seg)
  62
  63 #endif /* __ASSEMBLY__ */
  64
  65 #endif /* _M68K_SEGMENT_H */