include/asm-arm26/uaccess-asm.h

   1 /*
   2  *  linux/include/asm-arm/proc-armo/uaccess.h
   3  *
   4  *  Copyright (C) 1996 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 /*
  12  * The fs functions are implemented on the ARM2 and ARM3 architectures
  13  * manually.
  14  * Use *_user functions to access user memory with faulting behaving
  15  *   as though the user is accessing the memory.
  16  * Use set_fs(get_ds()) and then the *_user functions to allow them to
  17  *   access kernel memory.
  18  */
  19
  20 /*
  21  * These are the values used to represent the user `fs' and the kernel `ds'
  22  * FIXME - the KERNEL_DS should end at 0x03000000 but we want to access ROM at
  23  * 0x03400000. ideally we want to forbid access to the IO space inbetween.
  24  */
  25 #define KERNEL_DS       0x03FFFFFF
  26 #define USER_DS         0x02000000
  27
  28 extern uaccess_t uaccess_user, uaccess_kernel;
  29
  30 static inline void set_fs (mm_segment_t fs)
  31 {
  32         current_thread_info()->addr_limit = fs;
  33         current->thread.uaccess = (fs == USER_DS ? &uaccess_user : &uaccess_kernel);
  34 }
  35
  36 #define __range_ok(addr,size) ({                                        \
  37         unsigned long flag, roksum;                                     \
  38         __asm__ __volatile__("subs %1, %0, %3; cmpcs %1, %2; movcs %0, #0" \
  39                 : "=&r" (flag), "=&r" (roksum)                          \
  40                 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit)      \
  41                 : "cc");                                                \
  42         flag; })
  43
  44 #define __addr_ok(addr) ({                                              \
  45         unsigned long flag;                                             \
  46         __asm__ __volatile__("cmp %2, %0; movlo %0, #0"                 \
  47                 : "=&r" (flag)                                          \
  48                 : "0" (current_thread_info()->addr_limit), "r" (addr)   \
  49                 : "cc");                                                \
  50         (flag == 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->thread.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->thread.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->thread.uaccess->put_word), \
  88           "0" (err)                                                     \
  89         : "r0", "r1", "r2", "lr")
  90
  91 #define __put_user_asm_dword(x,addr,err)                                 \
  92         __asm__ __volatile__(                                           \
  93         "       mov     r0, %1\n"                                       \
  94         "       mov     r1, %2\n"                                       \
  95         "       mov     r2, %0\n"                                       \
  96         "       mov     lr, pc\n"                                       \
  97         "       mov     pc, %3\n"                                       \
  98         "       mov     %0, r2\n"                                       \
  99         : "=r" (err)                                                    \
 100         : "r" (x), "r" (addr), "r" (current->thread.uaccess->put_dword), \
 101           "0" (err)                                                     \
 102         : "r0", "r1", "r2", "lr")
 103
 104 #define __get_user_asm_byte(x,addr,err)                                 \
 105         __asm__ __volatile__(                                           \
 106         "       mov     r0, %2\n"                                       \
 107         "       mov     r1, %0\n"                                       \
 108         "       mov     lr, pc\n"                                       \
 109         "       mov     pc, %3\n"                                       \
 110         "       mov     %0, r1\n"                                       \
 111         "       mov     %1, r0\n"                                       \
 112         : "=r" (err), "=r" (x)                                          \
 113         : "r" (addr), "r" (current->thread.uaccess->get_byte), "0" (err)        \
 114         : "r0", "r1", "r2", "lr")
 115
 116 #define __get_user_asm_half(x,addr,err)                                 \
 117         __asm__ __volatile__(                                           \
 118         "       mov     r0, %2\n"                                       \
 119         "       mov     r1, %0\n"                                       \
 120         "       mov     lr, pc\n"                                       \
 121         "       mov     pc, %3\n"                                       \
 122         "       mov     %0, r1\n"                                       \
 123         "       mov     %1, r0\n"                                       \
 124         : "=r" (err), "=r" (x)                                          \
 125         : "r" (addr), "r" (current->thread.uaccess->get_half), "0" (err)        \
 126         : "r0", "r1", "r2", "lr")
 127
 128 #define __get_user_asm_word(x,addr,err)                                 \
 129         __asm__ __volatile__(                                           \
 130         "       mov     r0, %2\n"                                       \
 131         "       mov     r1, %0\n"                                       \
 132         "       mov     lr, pc\n"                                       \
 133         "       mov     pc, %3\n"                                       \
 134         "       mov     %0, r1\n"                                       \
 135         "       mov     %1, r0\n"                                       \
 136         : "=r" (err), "=r" (x)                                          \
 137         : "r" (addr), "r" (current->thread.uaccess->get_word), "0" (err)        \
 138         : "r0", "r1", "r2", "lr")
 139
 140 #define __do_copy_from_user(to,from,n)                                  \
 141         (n) = current->thread.uaccess->copy_from_user((to),(from),(n))
 142
 143 #define __do_copy_to_user(to,from,n)                                    \
 144         (n) = current->thread.uaccess->copy_to_user((to),(from),(n))
 145
 146 #define __do_clear_user(addr,sz)                                        \
 147         (sz) = current->thread.uaccess->clear_user((addr),(sz))
 148
 149 #define __do_strncpy_from_user(dst,src,count,res)                       \
 150         (res) = current->thread.uaccess->strncpy_from_user(dst,src,count)
 151
 152 #define __do_strnlen_user(s,n,res)                                      \
 153         (res) = current->thread.uaccess->strnlen_user(s,n)