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 #endif 17 18 #ifndef __ASSEMBLY__ 19 20 #include <asm/processor.h> 21 22 /* 23 * Sparc64 is segmented, though more like the M68K than the I386. 24 * We use the secondary ASI to address user memory, which references a 25 * completely different VM map, thus there is zero chance of the user 26 * doing something queer and tricking us into poking kernel memory. 27 * 28 * What is left here is basically what is needed for the other parts of 29 * the kernel that expect to be able to manipulate, erum, "segments". 30 * Or perhaps more properly, permissions. 31 * 32 * "For historical reasons, these macros are grossly misnamed." -Linus 33 */ 34 35 #define KERNEL_DS ((mm_segment_t) { ASI_P }) 36 #define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */ 37 38 #define VERIFY_READ 0 39 #define VERIFY_WRITE 1 40 41 #define get_fs() ((mm_segment_t){(current_thread_info()->current_ds)}) 42 #define get_ds() (KERNEL_DS) 43 44 #define segment_eq(a, b) ((a).seg == (b).seg) 45 46 #define set_fs(val) \ 47 do { \ 48 current_thread_info()->current_ds = (val).seg; \ 49 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ 50 } while(0) 51 52 static inline int __access_ok(const void __user * addr, unsigned long size) 53 { 54 return 1; 55 } 56 57 static inline int access_ok(int type, const void __user * addr, unsigned long size) 58 { 59 return 1; 60 } 61 62 /* 63 * The exception table consists of pairs of addresses: the first is the 64 * address of an instruction that is allowed to fault, and the second is 65 * the address at which the program should continue. No registers are 66 * modified, so it is entirely up to the continuation code to figure out 67 * what to do. 68 * 69 * All the routines below use bits of fixup code that are out of line 70 * with the main instruction path. This means when everything is well, 71 * we don't even have to jump over them. Further, they do not intrude 72 * on our cache or tlb entries. 73 */ 74 75 struct exception_table_entry { 76 unsigned int insn, fixup; 77 }; 78 79 void __ret_efault(void); 80 void __retl_efault(void); 81 82 /* Uh, these should become the main single-value transfer routines.. 83 * They automatically use the right size if we just have the right 84 * pointer type.. 85 * 86 * This gets kind of ugly. We want to return _two_ values in "get_user()" 87 * and yet we don't want to do any pointers, because that is too much 88 * of a performance impact. Thus we have a few rather ugly macros here, 89 * and hide all the ugliness from the user. 90 */ 91 #define put_user(x, ptr) ({ \ 92 unsigned long __pu_addr = (unsigned long)(ptr); \ 93 __chk_user_ptr(ptr); \ 94 __put_user_nocheck((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr)));\ 95 }) 96 97 #define get_user(x, ptr) ({ \ 98 unsigned long __gu_addr = (unsigned long)(ptr); \ 99 __chk_user_ptr(ptr); \ 100 __get_user_nocheck((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr)));\ 101 }) 102 103 #define __put_user(x, ptr) put_user(x, ptr) 104 #define __get_user(x, ptr) get_user(x, ptr) 105 106 struct __large_struct { unsigned long buf[100]; }; 107 #define __m(x) ((struct __large_struct *)(x)) 108 109 #define __put_user_nocheck(data, addr, size) ({ \ 110 register int __pu_ret; \ 111 switch (size) { \ 112 case 1: __put_user_asm(data, b, addr, __pu_ret); break; \ 113 case 2: __put_user_asm(data, h, addr, __pu_ret); break; \ 114 case 4: __put_user_asm(data, w, addr, __pu_ret); break; \ 115 case 8: __put_user_asm(data, x, addr, __pu_ret); break; \ 116 default: __pu_ret = __put_user_bad(); break; \ 117 } \ 118 __pu_ret; \ 119 }) 120 121 #define __put_user_asm(x, size, addr, ret) \ 122 __asm__ __volatile__( \ 123 "/* Put user asm, inline. */\n" \ 124 "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ 125 "clr %0\n" \ 126 "2:\n\n\t" \ 127 ".section .fixup,#alloc,#execinstr\n\t" \ 128 ".align 4\n" \ 129 "3:\n\t" \ 130 "sethi %%hi(2b), %0\n\t" \ 131 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 132 " mov %3, %0\n\n\t" \ 133 ".previous\n\t" \ 134 ".section __ex_table,\"a\"\n\t" \ 135 ".align 4\n\t" \ 136 ".word 1b, 3b\n\t" \ 137 ".previous\n\n\t" \ 138 : "=r" (ret) : "r" (x), "r" (__m(addr)), \ 139 "i" (-EFAULT)) 140 141 int __put_user_bad(void); 142 143 #define __get_user_nocheck(data, addr, size, type) ({ \ 144 register int __gu_ret; \ 145 register unsigned long __gu_val; \ 146 switch (size) { \ 147 case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \ 148 case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \ 149 case 4: __get_user_asm(__gu_val, uw, addr, __gu_ret); break; \ 150 case 8: __get_user_asm(__gu_val, x, addr, __gu_ret); break; \ 151 default: \ 152 __gu_val = 0; \ 153 __gu_ret = __get_user_bad(); \ 154 break; \ 155 } \ 156 data = (__force type) __gu_val; \ 157 __gu_ret; \ 158 }) 159 160 #define __get_user_nocheck_ret(data, addr, size, type, retval) ({ \ 161 register unsigned long __gu_val __asm__ ("l1"); \ 162 switch (size) { \ 163 case 1: __get_user_asm_ret(__gu_val, ub, addr, retval); break; \ 164 case 2: __get_user_asm_ret(__gu_val, uh, addr, retval); break; \ 165 case 4: __get_user_asm_ret(__gu_val, uw, addr, retval); break; \ 166 case 8: __get_user_asm_ret(__gu_val, x, addr, retval); break; \ 167 default: \ 168 if (__get_user_bad()) \ 169 return retval; \ 170 } \ 171 data = (__force type) __gu_val; \ 172 }) 173 174 #define __get_user_asm(x, size, addr, ret) \ 175 __asm__ __volatile__( \ 176 "/* Get user asm, inline. */\n" \ 177 "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ 178 "clr %0\n" \ 179 "2:\n\n\t" \ 180 ".section .fixup,#alloc,#execinstr\n\t" \ 181 ".align 4\n" \ 182 "3:\n\t" \ 183 "sethi %%hi(2b), %0\n\t" \ 184 "clr %1\n\t" \ 185 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 186 " mov %3, %0\n\n\t" \ 187 ".previous\n\t" \ 188 ".section __ex_table,\"a\"\n\t" \ 189 ".align 4\n\t" \ 190 ".word 1b, 3b\n\n\t" \ 191 ".previous\n\t" \ 192 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ 193 "i" (-EFAULT)) 194 195 #define __get_user_asm_ret(x, size, addr, retval) \ 196 if (__builtin_constant_p(retval) && retval == -EFAULT) \ 197 __asm__ __volatile__( \ 198 "/* Get user asm ret, inline. */\n" \ 199 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 200 ".section __ex_table,\"a\"\n\t" \ 201 ".align 4\n\t" \ 202 ".word 1b,__ret_efault\n\n\t" \ 203 ".previous\n\t" \ 204 : "=r" (x) : "r" (__m(addr))); \ 205 else \ 206 __asm__ __volatile__( \ 207 "/* Get user asm ret, inline. */\n" \ 208 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 209 ".section .fixup,#alloc,#execinstr\n\t" \ 210 ".align 4\n" \ 211 "3:\n\t" \ 212 "ret\n\t" \ 213 " restore %%g0, %2, %%o0\n\n\t" \ 214 ".previous\n\t" \ 215 ".section __ex_table,\"a\"\n\t" \ 216 ".align 4\n\t" \ 217 ".word 1b, 3b\n\n\t" \ 218 ".previous\n\t" \ 219 : "=r" (x) : "r" (__m(addr)), "i" (retval)) 220 221 int __get_user_bad(void); 222 223 unsigned long __must_check ___copy_from_user(void *to, 224 const void __user *from, 225 unsigned long size); 226 unsigned long copy_from_user_fixup(void *to, const void __user *from, 227 unsigned long size); 228 static inline unsigned long __must_check 229 copy_from_user(void *to, const void __user *from, unsigned long size) 230 { 231 unsigned long ret = ___copy_from_user(to, from, size); 232 233 if (unlikely(ret)) 234 ret = copy_from_user_fixup(to, from, size); 235 236 return ret; 237 } 238 #define __copy_from_user copy_from_user 239 240 unsigned long __must_check ___copy_to_user(void __user *to, 241 const void *from, 242 unsigned long size); 243 unsigned long copy_to_user_fixup(void __user *to, const void *from, 244 unsigned long size); 245 static inline unsigned long __must_check 246 copy_to_user(void __user *to, const void *from, unsigned long size) 247 { 248 unsigned long ret = ___copy_to_user(to, from, size); 249 250 if (unlikely(ret)) 251 ret = copy_to_user_fixup(to, from, size); 252 return ret; 253 } 254 #define __copy_to_user copy_to_user 255 256 unsigned long __must_check ___copy_in_user(void __user *to, 257 const void __user *from, 258 unsigned long size); 259 unsigned long copy_in_user_fixup(void __user *to, void __user *from, 260 unsigned long size); 261 static inline unsigned long __must_check 262 copy_in_user(void __user *to, void __user *from, unsigned long size) 263 { 264 unsigned long ret = ___copy_in_user(to, from, size); 265 266 if (unlikely(ret)) 267 ret = copy_in_user_fixup(to, from, size); 268 return ret; 269 } 270 #define __copy_in_user copy_in_user 271 272 unsigned long __must_check __clear_user(void __user *, unsigned long); 273 274 #define clear_user __clear_user 275 276 __must_check long strlen_user(const char __user *str); 277 __must_check long strnlen_user(const char __user *str, long n); 278 279 #define __copy_to_user_inatomic __copy_to_user 280 #define __copy_from_user_inatomic __copy_from_user 281 282 struct pt_regs; 283 unsigned long compute_effective_address(struct pt_regs *, 284 unsigned int insn, 285 unsigned int rd); 286 287 #endif /* __ASSEMBLY__ */ 288 289 #endif /* _ASM_UACCESS_H */ 290