include/asm-arm/proc-armo/uaccess.h

   1 /*
   2  * linux/include/asm-arm/proc-armo/segment.h
   3  *
   4  * Copyright (C) 1996 Russell King
   5  */
   6
   7 /*
   8  * The fs functions are implemented on the ARM2 and ARM3 architectures
   9  * manually.
  10  * Use *_user functions to access user memory with faulting behaving
  11  *   as though the user is accessing the memory.
  12  * Use set_fs(get_ds()) and then the *_user functions to allow them to
  13  *   access kernel memory.
  14  */
  15
  16 /*
  17  * These are the values used to represent the user `fs' and the kernel `ds'
  18  */
  19 #define KERNEL_DS       0x03000000
  20 #define USER_DS         0x02000000
  21
  22 #define get_ds()        (KERNEL_DS)
  23 #define get_fs()        (current->addr_limit)
  24 #define segment_eq(a,b) ((a) == (b))
  25
  26 extern uaccess_t uaccess_user, uaccess_kernel;
  27
  28 extern __inline__ void set_fs (mm_segment_t fs)
  29 {
  30         current->addr_limit = fs;
  31         current->tss.uaccess = fs == USER_DS ? &uaccess_user : &uaccess_kernel;
  32 }
  33
  34 #define __range_ok(addr,size) ({                                        \
  35         unsigned long flag, sum;                                        \
  36         __asm__ __volatile__("subs %1, %0, %3; cmpcs %1, %2; movcs %0, #0" \
  37                 : "=&r" (flag), "=&r" (sum)                             \
  38                 : "r" (addr), "Ir" (size), "0" (current->addr_limit)    \
  39                 : "cc");                                                \
  40         flag; })
  41
  42 #define __addr_ok(addr) ({                                              \
  43         unsigned long flag;                                             \
  44         __asm__ __volatile__("cmp %2, %0; movlo %0, #0"                 \
  45                 : "=&r" (flag)                                          \
  46                 : "0" (current->addr_limit), "r" (addr)                 \
  47                 : "cc");                                                \
  48         (flag == 0); })
  49
  50 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
  51
  52 #define __put_user_asm_byte(x,addr,err)                                 \
  53         __asm__ __volatile__(                                           \
  54         "       mov     r0, %1\n"                                       \
  55         "       mov     r1, %2\n"                                       \
  56         "       mov     r2, %0\n"                                       \
  57         "       mov     lr, pc\n"                                       \
  58         "       mov     pc, %3\n"                                       \
  59         "       mov     %0, r2\n"                                       \
  60         : "=r" (err)                                                    \
  61         : "r" (x), "r" (addr), "r" (current->tss.uaccess->put_byte),    \
  62           "0" (err)                                                     \
  63         : "r0", "r1", "r2", "lr")
  64
  65 #define __put_user_asm_half(x,addr,err)                                 \
  66         __asm__ __volatile__(                                           \
  67         "       mov     r0, %1\n"                                       \
  68         "       mov     r1, %2\n"                                       \
  69         "       mov     r2, %0\n"                                       \
  70         "       mov     lr, pc\n"                                       \
  71         "       mov     pc, %3\n"                                       \
  72         "       mov     %0, r2\n"                                       \
  73         : "=r" (err)                                                    \
  74         : "r" (x), "r" (addr), "r" (current->tss.uaccess->put_half),    \
  75           "0" (err)                                                     \
  76         : "r0", "r1", "r2", "lr")
  77
  78 #define __put_user_asm_word(x,addr,err)                                 \
  79         __asm__ __volatile__(                                           \
  80         "       mov     r0, %1\n"                                       \
  81         "       mov     r1, %2\n"                                       \
  82         "       mov     r2, %0\n"                                       \
  83         "       mov     lr, pc\n"                                       \
  84         "       mov     pc, %3\n"                                       \
  85         "       mov     %0, r2\n"                                       \
  86         : "=r" (err)                                                    \
  87         : "r" (x), "r" (addr), "r" (current->tss.uaccess->put_word),    \
  88           "0" (err)                                                     \
  89         : "r0", "r1", "r2", "lr")
  90
  91 #define __get_user_asm_byte(x,addr,err)                                 \
  92         __asm__ __volatile__(                                           \
  93         "       mov     r0, %2\n"                                       \
  94         "       mov     r1, %0\n"                                       \
  95         "       mov     lr, pc\n"                                       \
  96         "       mov     pc, %3\n"                                       \
  97         "       mov     %0, r1\n"                                       \
  98         "       mov     %1, r0\n"                                       \
  99         : "=r" (err), "=r" (x)                                          \
 100         : "r" (addr), "r" (current->tss.uaccess->get_byte), "0" (err)   \
 101         : "r0", "r1", "r2", "lr")
 102
 103 #define __get_user_asm_half(x,addr,err)                                 \
 104         __asm__ __volatile__(                                           \
 105         "       mov     r0, %2\n"                                       \
 106         "       mov     r1, %0\n"                                       \
 107         "       mov     lr, pc\n"                                       \
 108         "       mov     pc, %3\n"                                       \
 109         "       mov     %0, r1\n"                                       \
 110         "       mov     %1, r0\n"                                       \
 111         : "=r" (err), "=r" (x)                                          \
 112         : "r" (addr), "r" (current->tss.uaccess->get_half), "0" (err)   \
 113         : "r0", "r1", "r2", "lr")
 114
 115 #define __get_user_asm_word(x,addr,err)                                 \
 116         __asm__ __volatile__(                                           \
 117         "       mov     r0, %2\n"                                       \
 118         "       mov     r1, %0\n"                                       \
 119         "       mov     lr, pc\n"                                       \
 120         "       mov     pc, %3\n"                                       \
 121         "       mov     %0, r1\n"                                       \
 122         "       mov     %1, r0\n"                                       \
 123         : "=r" (err), "=r" (x)                                          \
 124         : "r" (addr), "r" (current->tss.uaccess->get_word), "0" (err)   \
 125         : "r0", "r1", "r2", "lr")
 126
 127 #define __do_copy_from_user(to,from,n)                                  \
 128         (n) = current->tss.uaccess->copy_from_user((to),(from),(n))
 129
 130 #define __do_copy_to_user(to,from,n)                                    \
 131         (n) = current->tss.uaccess->copy_to_user((to),(from),(n))
 132
 133 #define __do_clear_user(addr,sz)                                        \
 134         (sz) = current->tss.uaccess->clear_user((addr),(sz))
 135
 136 #define __do_strncpy_from_user(dst,src,count,res)                       \
 137         (res) = current->tss.uaccess->strncpy_from_user(dst,src,count)
 138
 139 #define __do_strlen_user(s,res)                                         \
 140         (res) = current->tss.uaccess->strlen_user(s)