arch/sparc/include/asm/uaccess_64.h

   1 #ifndef _ASM_UACCESS_H
   2 #define _ASM_UACCESS_H
   3
   4 /*
   5  * User space memory access functions
   6  */
   7
   8 #ifdef __KERNEL__
   9 #include <linux/errno.h>
  10 #include <linux/compiler.h>
  11 #include <linux/string.h>
  12 #include <linux/thread_info.h>
  13 #include <asm/asi.h>
  14 #include <asm/spitfire.h>
  15 #include <asm-generic/uaccess-unaligned.h>
  16 #include <asm/extable_64.h>
  17 #endif
  18
  19 #ifndef __ASSEMBLY__
  20
  21 #include <asm/processor.h>
  22
  23 /*
  24  * Sparc64 is segmented, though more like the M68K than the I386.
  25  * We use the secondary ASI to address user memory, which references a
  26  * completely different VM map, thus there is zero chance of the user
  27  * doing something queer and tricking us into poking kernel memory.
  28  *
  29  * What is left here is basically what is needed for the other parts of
  30  * the kernel that expect to be able to manipulate, erum, "segments".
  31  * Or perhaps more properly, permissions.
  32  *
  33  * "For historical reasons, these macros are grossly misnamed." -Linus
  34  */
  35
  36 #define KERNEL_DS   ((mm_segment_t) { ASI_P })
  37 #define USER_DS     ((mm_segment_t) { ASI_AIUS })       /* har har har */
  38
  39 #define VERIFY_READ     0
  40 #define VERIFY_WRITE    1
  41
  42 #define get_fs() ((mm_segment_t){(current_thread_info()->current_ds)})
  43 #define get_ds() (KERNEL_DS)
  44
  45 #define segment_eq(a, b)  ((a).seg == (b).seg)
  46
  47 #define set_fs(val)                                                             \
  48 do {                                                                            \
  49         current_thread_info()->current_ds = (val).seg;                          \
  50         __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg));        \
  51 } while(0)
  52
  53 /*
  54  * Test whether a block of memory is a valid user space address.
  55  * Returns 0 if the range is valid, nonzero otherwise.
  56  */
  57 static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, unsigned long limit)
  58 {
  59         if (__builtin_constant_p(size))
  60                 return addr > limit - size;
  61
  62         addr += size;
  63         if (addr < size)
  64                 return true;
  65
  66         return addr > limit;
  67 }
  68
  69 #define __range_not_ok(addr, size, limit)                               \
  70 ({                                                                      \
  71         __chk_user_ptr(addr);                                           \
  72         __chk_range_not_ok((unsigned long __force)(addr), size, limit); \
  73 })
  74
  75 static inline int __access_ok(const void __user * addr, unsigned long size)
  76 {
  77         return 1;
  78 }
  79
  80 static inline int access_ok(int type, const void __user * addr, unsigned long size)
  81 {
  82         return 1;
  83 }
  84
  85 void __ret_efault(void);
  86 void __retl_efault(void);
  87
  88 /* Uh, these should become the main single-value transfer routines..
  89  * They automatically use the right size if we just have the right
  90  * pointer type..
  91  *
  92  * This gets kind of ugly. We want to return _two_ values in "get_user()"
  93  * and yet we don't want to do any pointers, because that is too much
  94  * of a performance impact. Thus we have a few rather ugly macros here,
  95  * and hide all the ugliness from the user.
  96  */
  97 #define put_user(x, ptr) ({ \
  98         unsigned long __pu_addr = (unsigned long)(ptr); \
  99         __chk_user_ptr(ptr); \
 100         __put_user_nocheck((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr)));\
 101 })
 102
 103 #define get_user(x, ptr) ({ \
 104         unsigned long __gu_addr = (unsigned long)(ptr); \
 105         __chk_user_ptr(ptr); \
 106         __get_user_nocheck((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr)));\
 107 })
 108
 109 #define __put_user(x, ptr) put_user(x, ptr)
 110 #define __get_user(x, ptr) get_user(x, ptr)
 111
 112 struct __large_struct { unsigned long buf[100]; };
 113 #define __m(x) ((struct __large_struct *)(x))
 114
 115 #define __put_user_nocheck(data, addr, size) ({                 \
 116         register int __pu_ret;                                  \
 117         switch (size) {                                         \
 118         case 1: __put_user_asm(data, b, addr, __pu_ret); break; \
 119         case 2: __put_user_asm(data, h, addr, __pu_ret); break; \
 120         case 4: __put_user_asm(data, w, addr, __pu_ret); break; \
 121         case 8: __put_user_asm(data, x, addr, __pu_ret); break; \
 122         default: __pu_ret = __put_user_bad(); break;            \
 123         }                                                       \
 124         __pu_ret;                                               \
 125 })
 126
 127 #define __put_user_asm(x, size, addr, ret)                              \
 128 __asm__ __volatile__(                                                   \
 129                 "/* Put user asm, inline. */\n"                         \
 130         "1:\t"  "st"#size "a %1, [%2] %%asi\n\t"                        \
 131                 "clr    %0\n"                                           \
 132         "2:\n\n\t"                                                      \
 133                 ".section .fixup,#alloc,#execinstr\n\t"                 \
 134                 ".align 4\n"                                            \
 135         "3:\n\t"                                                        \
 136                 "sethi  %%hi(2b), %0\n\t"                               \
 137                 "jmpl   %0 + %%lo(2b), %%g0\n\t"                        \
 138                 " mov   %3, %0\n\n\t"                                   \
 139                 ".previous\n\t"                                         \
 140                 ".section __ex_table,\"a\"\n\t"                         \
 141                 ".align 4\n\t"                                          \
 142                 ".word  1b, 3b\n\t"                                     \
 143                 ".previous\n\n\t"                                       \
 144                : "=r" (ret) : "r" (x), "r" (__m(addr)),                 \
 145                  "i" (-EFAULT))
 146
 147 int __put_user_bad(void);
 148
 149 #define __get_user_nocheck(data, addr, size, type) ({                        \
 150         register int __gu_ret;                                               \
 151         register unsigned long __gu_val;                                     \
 152         switch (size) {                                                      \
 153                 case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \
 154                 case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \
 155                 case 4: __get_user_asm(__gu_val, uw, addr, __gu_ret); break; \
 156                 case 8: __get_user_asm(__gu_val, x, addr, __gu_ret); break;  \
 157                 default:                                                     \
 158                         __gu_val = 0;                                        \
 159                         __gu_ret = __get_user_bad();                         \
 160                         break;                                               \
 161         }                                                                    \
 162         data = (__force type) __gu_val;                                      \
 163          __gu_ret;                                                           \
 164 })
 165
 166 #define __get_user_asm(x, size, addr, ret)                              \
 167 __asm__ __volatile__(                                                   \
 168                 "/* Get user asm, inline. */\n"                         \
 169         "1:\t"  "ld"#size "a [%2] %%asi, %1\n\t"                        \
 170                 "clr    %0\n"                                           \
 171         "2:\n\n\t"                                                      \
 172                 ".section .fixup,#alloc,#execinstr\n\t"                 \
 173                 ".align 4\n"                                            \
 174         "3:\n\t"                                                        \
 175                 "sethi  %%hi(2b), %0\n\t"                               \
 176                 "clr    %1\n\t"                                         \
 177                 "jmpl   %0 + %%lo(2b), %%g0\n\t"                        \
 178                 " mov   %3, %0\n\n\t"                                   \
 179                 ".previous\n\t"                                         \
 180                 ".section __ex_table,\"a\"\n\t"                         \
 181                 ".align 4\n\t"                                          \
 182                 ".word  1b, 3b\n\n\t"                                   \
 183                 ".previous\n\t"                                         \
 184                : "=r" (ret), "=r" (x) : "r" (__m(addr)),                \
 185                  "i" (-EFAULT))
 186
 187 int __get_user_bad(void);
 188
 189 unsigned long __must_check ___copy_from_user(void *to,
 190                                              const void __user *from,
 191                                              unsigned long size);
 192 unsigned long copy_from_user_fixup(void *to, const void __user *from,
 193                                    unsigned long size);
 194 static inline unsigned long __must_check
 195 copy_from_user(void *to, const void __user *from, unsigned long size)
 196 {
 197         unsigned long ret;
 198
 199         check_object_size(to, size, false);
 200
 201         ret = ___copy_from_user(to, from, size);
 202         if (unlikely(ret))
 203                 ret = copy_from_user_fixup(to, from, size);
 204
 205         return ret;
 206 }
 207 #define __copy_from_user copy_from_user
 208
 209 unsigned long __must_check ___copy_to_user(void __user *to,
 210                                            const void *from,
 211                                            unsigned long size);
 212 unsigned long copy_to_user_fixup(void __user *to, const void *from,
 213                                  unsigned long size);
 214 static inline unsigned long __must_check
 215 copy_to_user(void __user *to, const void *from, unsigned long size)
 216 {
 217         unsigned long ret;
 218
 219         check_object_size(from, size, true);
 220
 221         ret = ___copy_to_user(to, from, size);
 222         if (unlikely(ret))
 223                 ret = copy_to_user_fixup(to, from, size);
 224         return ret;
 225 }
 226 #define __copy_to_user copy_to_user
 227
 228 unsigned long __must_check ___copy_in_user(void __user *to,
 229                                            const void __user *from,
 230                                            unsigned long size);
 231 unsigned long copy_in_user_fixup(void __user *to, void __user *from,
 232                                  unsigned long size);
 233 static inline unsigned long __must_check
 234 copy_in_user(void __user *to, void __user *from, unsigned long size)
 235 {
 236         unsigned long ret = ___copy_in_user(to, from, size);
 237
 238         if (unlikely(ret))
 239                 ret = copy_in_user_fixup(to, from, size);
 240         return ret;
 241 }
 242 #define __copy_in_user copy_in_user
 243
 244 unsigned long __must_check __clear_user(void __user *, unsigned long);
 245
 246 #define clear_user __clear_user
 247
 248 __must_check long strlen_user(const char __user *str);
 249 __must_check long strnlen_user(const char __user *str, long n);
 250
 251 #define __copy_to_user_inatomic __copy_to_user
 252 #define __copy_from_user_inatomic __copy_from_user
 253
 254 struct pt_regs;
 255 unsigned long compute_effective_address(struct pt_regs *,
 256                                         unsigned int insn,
 257                                         unsigned int rd);
 258
 259 #endif  /* __ASSEMBLY__ */
 260
 261 #endif /* _ASM_UACCESS_H */