arch/c6x/include/asm/uaccess.h

   1 /*
   2  *  Copyright (C) 2011 Texas Instruments Incorporated
   3  *  Author: Mark Salter <msalter@redhat.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License version 2 as
   7  *  published by the Free Software Foundation.
   8  */
   9 #ifndef _ASM_C6X_UACCESS_H
  10 #define _ASM_C6X_UACCESS_H
  11
  12 #include <linux/types.h>
  13 #include <linux/compiler.h>
  14 #include <linux/string.h>
  15
  16 /*
  17  * C6X supports unaligned 32 and 64 bit loads and stores.
  18  */
  19 static inline __must_check unsigned long
  20 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
  21 {
  22         u32 tmp32;
  23         u64 tmp64;
  24
  25         if (__builtin_constant_p(n)) {
  26                 switch (n) {
  27                 case 1:
  28                         *(u8 *)to = *(u8 __force *)from;
  29                         return 0;
  30                 case 4:
  31                         asm volatile ("ldnw .d1t1 *%2,%0\n"
  32                                       "nop  4\n"
  33                                       "stnw .d1t1 %0,*%1\n"
  34                                       : "=&a"(tmp32)
  35                                       : "A"(to), "a"(from)
  36                                       : "memory");
  37                         return 0;
  38                 case 8:
  39                         asm volatile ("ldndw .d1t1 *%2,%0\n"
  40                                       "nop   4\n"
  41                                       "stndw .d1t1 %0,*%1\n"
  42                                       : "=&a"(tmp64)
  43                                       : "a"(to), "a"(from)
  44                                       : "memory");
  45                         return 0;
  46                 default:
  47                         break;
  48                 }
  49         }
  50
  51         memcpy(to, (const void __force *)from, n);
  52         return 0;
  53 }
  54
  55 static inline __must_check unsigned long
  56 raw_copy_to_user(void __user *to, const void *from, unsigned long n)
  57 {
  58         u32 tmp32;
  59         u64 tmp64;
  60
  61         if (__builtin_constant_p(n)) {
  62                 switch (n) {
  63                 case 1:
  64                         *(u8 __force *)to = *(u8 *)from;
  65                         return 0;
  66                 case 4:
  67                         asm volatile ("ldnw .d1t1 *%2,%0\n"
  68                                       "nop  4\n"
  69                                       "stnw .d1t1 %0,*%1\n"
  70                                       : "=&a"(tmp32)
  71                                       : "a"(to), "a"(from)
  72                                       : "memory");
  73                         return 0;
  74                 case 8:
  75                         asm volatile ("ldndw .d1t1 *%2,%0\n"
  76                                       "nop   4\n"
  77                                       "stndw .d1t1 %0,*%1\n"
  78                                       : "=&a"(tmp64)
  79                                       : "a"(to), "a"(from)
  80                                       : "memory");
  81                         return 0;
  82                 default:
  83                         break;
  84                 }
  85         }
  86
  87         memcpy((void __force *)to, from, n);
  88         return 0;
  89 }
  90 #define INLINE_COPY_FROM_USER
  91 #define INLINE_COPY_TO_USER
  92
  93 extern int _access_ok(unsigned long addr, unsigned long size);
  94 #ifdef CONFIG_ACCESS_CHECK
  95 #define __access_ok _access_ok
  96 #endif
  97
  98 #include <asm-generic/uaccess.h>
  99
 100 #endif /* _ASM_C6X_UACCESS_H */