include/asm-h8300/uaccess.h

   1 #ifndef __H8300_UACCESS_H
   2 #define __H8300_UACCESS_H
   3
   4 /*
   5  * User space memory access functions
   6  */
   7 #include <linux/sched.h>
   8 #include <linux/mm.h>
   9 #include <linux/string.h>
  10
  11 #include <asm/segment.h>
  12
  13 #define VERIFY_READ     0
  14 #define VERIFY_WRITE    1
  15
  16 /* We let the MMU do all checking */
  17 #define access_ok(type, addr, size) __access_ok((unsigned long)addr,size)
  18 static inline int __access_ok(unsigned long addr, unsigned long size)
  19 {
  20 #define RANGE_CHECK_OK(addr, size, lower, upper) \
  21         (((addr) >= (lower)) && (((addr) + (size)) < (upper)))
  22
  23         extern unsigned long _ramend;
  24         return(RANGE_CHECK_OK(addr, size, 0L, (unsigned long)&_ramend));
  25 }
  26
  27 /* this function will go away soon - use access_ok() instead */
  28 static inline int __deprecated verify_area(int type, const void *addr, unsigned long size)
  29 {
  30         return access_ok(type,addr,size)?0:-EFAULT;
  31 }
  32
  33 /*
  34  * The exception table consists of pairs of addresses: the first is the
  35  * address of an instruction that is allowed to fault, and the second is
  36  * the address at which the program should continue.  No registers are
  37  * modified, so it is entirely up to the continuation code to figure out
  38  * what to do.
  39  *
  40  * All the routines below use bits of fixup code that are out of line
  41  * with the main instruction path.  This means when everything is well,
  42  * we don't even have to jump over them.  Further, they do not intrude
  43  * on our cache or tlb entries.
  44  */
  45
  46 struct exception_table_entry
  47 {
  48         unsigned long insn, fixup;
  49 };
  50
  51 /* Returns 0 if exception not found and fixup otherwise.  */
  52 extern unsigned long search_exception_table(unsigned long);
  53
  54
  55 /*
  56  * These are the main single-value transfer routines.  They automatically
  57  * use the right size if we just have the right pointer type.
  58  */
  59
  60 #define put_user(x, ptr)                                \
  61 ({                                                      \
  62     int __pu_err = 0;                                   \
  63     typeof(*(ptr)) __pu_val = (x);                      \
  64     switch (sizeof (*(ptr))) {                          \
  65     case 1:                                             \
  66     case 2:                                             \
  67     case 4:                                             \
  68         *(ptr) = (__pu_val);                            \
  69         break;                                          \
  70     case 8:                                             \
  71         memcpy(ptr, &__pu_val, sizeof (*(ptr)));        \
  72         break;                                          \
  73     default:                                            \
  74         __pu_err = __put_user_bad();                    \
  75         break;                                          \
  76     }                                                   \
  77     __pu_err;                                           \
  78 })
  79 #define __put_user(x, ptr) put_user(x, ptr)
  80
  81 extern int __put_user_bad(void);
  82
  83 /*
  84  * Tell gcc we read from memory instead of writing: this is because
  85  * we do not write to any memory gcc knows about, so there are no
  86  * aliasing issues.
  87  */
  88
  89 #define __ptr(x) ((unsigned long *)(x))
  90
  91 /*
  92  * Tell gcc we read from memory instead of writing: this is because
  93  * we do not write to any memory gcc knows about, so there are no
  94  * aliasing issues.
  95  */
  96
  97 #define get_user(x, ptr)                                        \
  98 ({                                                              \
  99     int __gu_err = 0;                                           \
 100     typeof(*(ptr)) __gu_val = 0;                                \
 101     switch (sizeof(*(ptr))) {                                   \
 102     case 1:                                                     \
 103     case 2:                                                     \
 104     case 4:                                                     \
 105         __gu_val = *(ptr);                                      \
 106         break;                                                  \
 107     case 8:                                                     \
 108         memcpy(&__gu_val, ptr, sizeof (*(ptr)));                \
 109         break;                                                  \
 110     default:                                                    \
 111         __gu_val = 0;                                           \
 112         __gu_err = __get_user_bad();                            \
 113         break;                                                  \
 114     }                                                           \
 115     (x) = __gu_val;                                             \
 116     __gu_err;                                                   \
 117 })
 118 #define __get_user(x, ptr) get_user(x, ptr)
 119
 120 extern int __get_user_bad(void);
 121
 122 #define copy_from_user(to, from, n)             (memcpy(to, from, n), 0)
 123 #define copy_to_user(to, from, n)               (memcpy(to, from, n), 0)
 124
 125 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
 126 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
 127 #define __copy_to_user_inatomic __copy_to_user
 128 #define __copy_from_user_inatomic __copy_from_user
 129
 130 #define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; })
 131
 132 #define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; })
 133
 134 /*
 135  * Copy a null terminated string from userspace.
 136  */
 137
 138 static inline long
 139 strncpy_from_user(char *dst, const char *src, long count)
 140 {
 141         char *tmp;
 142         strncpy(dst, src, count);
 143         for (tmp = dst; *tmp && count > 0; tmp++, count--)
 144                 ;
 145         return(tmp - dst); /* DAVIDM should we count a NUL ?  check getname */
 146 }
 147
 148 /*
 149  * Return the size of a string (including the ending 0)
 150  *
 151  * Return 0 on exception, a value greater than N if too long
 152  */
 153 static inline long strnlen_user(const char *src, long n)
 154 {
 155         return(strlen(src) + 1); /* DAVIDM make safer */
 156 }
 157
 158 #define strlen_user(str) strnlen_user(str, 32767)
 159
 160 /*
 161  * Zero Userspace
 162  */
 163
 164 static inline unsigned long
 165 clear_user(void *to, unsigned long n)
 166 {
 167         memset(to, 0, n);
 168         return 0;
 169 }
 170
 171 #endif /* _H8300_UACCESS_H */