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/system.h> 15 #include <asm/spitfire.h> 16 #include <asm-generic/uaccess-unaligned.h> 17 #endif 18 19 #ifndef __ASSEMBLY__ 20 21 /* 22 * Sparc64 is segmented, though more like the M68K than the I386. 23 * We use the secondary ASI to address user memory, which references a 24 * completely different VM map, thus there is zero chance of the user 25 * doing something queer and tricking us into poking kernel memory. 26 * 27 * What is left here is basically what is needed for the other parts of 28 * the kernel that expect to be able to manipulate, erum, "segments". 29 * Or perhaps more properly, permissions. 30 * 31 * "For historical reasons, these macros are grossly misnamed." -Linus 32 */ 33 34 #define KERNEL_DS ((mm_segment_t) { ASI_P }) 35 #define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */ 36 37 #define VERIFY_READ 0 38 #define VERIFY_WRITE 1 39 40 #define get_fs() ((mm_segment_t) { get_thread_current_ds() }) 41 #define get_ds() (KERNEL_DS) 42 43 #define segment_eq(a,b) ((a).seg == (b).seg) 44 45 #define set_fs(val) \ 46 do { \ 47 set_thread_current_ds((val).seg); \ 48 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ 49 } while(0) 50 51 static inline int __access_ok(const void __user * addr, unsigned long size) 52 { 53 return 1; 54 } 55 56 static inline int access_ok(int type, const void __user * addr, unsigned long size) 57 { 58 return 1; 59 } 60 61 /* 62 * The exception table consists of pairs of addresses: the first is the 63 * address of an instruction that is allowed to fault, and the second is 64 * the address at which the program should continue. No registers are 65 * modified, so it is entirely up to the continuation code to figure out 66 * what to do. 67 * 68 * All the routines below use bits of fixup code that are out of line 69 * with the main instruction path. This means when everything is well, 70 * we don't even have to jump over them. Further, they do not intrude 71 * on our cache or tlb entries. 72 */ 73 74 struct exception_table_entry { 75 unsigned int insn, fixup; 76 }; 77 78 extern void __ret_efault(void); 79 extern void __retl_efault(void); 80 81 /* Uh, these should become the main single-value transfer routines.. 82 * They automatically use the right size if we just have the right 83 * pointer type.. 84 * 85 * This gets kind of ugly. We want to return _two_ values in "get_user()" 86 * and yet we don't want to do any pointers, because that is too much 87 * of a performance impact. Thus we have a few rather ugly macros here, 88 * and hide all the ugliness from the user. 89 */ 90 #define put_user(x,ptr) ({ \ 91 unsigned long __pu_addr = (unsigned long)(ptr); \ 92 __chk_user_ptr(ptr); \ 93 __put_user_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); }) 94 95 #define get_user(x,ptr) ({ \ 96 unsigned long __gu_addr = (unsigned long)(ptr); \ 97 __chk_user_ptr(ptr); \ 98 __get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); }) 99 100 #define __put_user(x,ptr) put_user(x,ptr) 101 #define __get_user(x,ptr) get_user(x,ptr) 102 103 struct __large_struct { unsigned long buf[100]; }; 104 #define __m(x) ((struct __large_struct *)(x)) 105 106 #define __put_user_nocheck(data,addr,size) ({ \ 107 register int __pu_ret; \ 108 switch (size) { \ 109 case 1: __put_user_asm(data,b,addr,__pu_ret); break; \ 110 case 2: __put_user_asm(data,h,addr,__pu_ret); break; \ 111 case 4: __put_user_asm(data,w,addr,__pu_ret); break; \ 112 case 8: __put_user_asm(data,x,addr,__pu_ret); break; \ 113 default: __pu_ret = __put_user_bad(); break; \ 114 } __pu_ret; }) 115 116 #define __put_user_asm(x,size,addr,ret) \ 117 __asm__ __volatile__( \ 118 "/* Put user asm, inline. */\n" \ 119 "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ 120 "clr %0\n" \ 121 "2:\n\n\t" \ 122 ".section .fixup,#alloc,#execinstr\n\t" \ 123 ".align 4\n" \ 124 "3:\n\t" \ 125 "sethi %%hi(2b), %0\n\t" \ 126 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 127 " mov %3, %0\n\n\t" \ 128 ".previous\n\t" \ 129 ".section __ex_table,\"a\"\n\t" \ 130 ".align 4\n\t" \ 131 ".word 1b, 3b\n\t" \ 132 ".previous\n\n\t" \ 133 : "=r" (ret) : "r" (x), "r" (__m(addr)), \ 134 "i" (-EFAULT)) 135 136 extern int __put_user_bad(void); 137 138 #define __get_user_nocheck(data,addr,size,type) ({ \ 139 register int __gu_ret; \ 140 register unsigned long __gu_val; \ 141 switch (size) { \ 142 case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \ 143 case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \ 144 case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \ 145 case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \ 146 default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \ 147 } data = (type) __gu_val; __gu_ret; }) 148 149 #define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \ 150 register unsigned long __gu_val __asm__ ("l1"); \ 151 switch (size) { \ 152 case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \ 153 case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \ 154 case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \ 155 case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \ 156 default: if (__get_user_bad()) return retval; \ 157 } data = (type) __gu_val; }) 158 159 #define __get_user_asm(x,size,addr,ret) \ 160 __asm__ __volatile__( \ 161 "/* Get user asm, inline. */\n" \ 162 "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ 163 "clr %0\n" \ 164 "2:\n\n\t" \ 165 ".section .fixup,#alloc,#execinstr\n\t" \ 166 ".align 4\n" \ 167 "3:\n\t" \ 168 "sethi %%hi(2b), %0\n\t" \ 169 "clr %1\n\t" \ 170 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 171 " mov %3, %0\n\n\t" \ 172 ".previous\n\t" \ 173 ".section __ex_table,\"a\"\n\t" \ 174 ".align 4\n\t" \ 175 ".word 1b, 3b\n\n\t" \ 176 ".previous\n\t" \ 177 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ 178 "i" (-EFAULT)) 179 180 #define __get_user_asm_ret(x,size,addr,retval) \ 181 if (__builtin_constant_p(retval) && retval == -EFAULT) \ 182 __asm__ __volatile__( \ 183 "/* Get user asm ret, inline. */\n" \ 184 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 185 ".section __ex_table,\"a\"\n\t" \ 186 ".align 4\n\t" \ 187 ".word 1b,__ret_efault\n\n\t" \ 188 ".previous\n\t" \ 189 : "=r" (x) : "r" (__m(addr))); \ 190 else \ 191 __asm__ __volatile__( \ 192 "/* Get user asm ret, inline. */\n" \ 193 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 194 ".section .fixup,#alloc,#execinstr\n\t" \ 195 ".align 4\n" \ 196 "3:\n\t" \ 197 "ret\n\t" \ 198 " restore %%g0, %2, %%o0\n\n\t" \ 199 ".previous\n\t" \ 200 ".section __ex_table,\"a\"\n\t" \ 201 ".align 4\n\t" \ 202 ".word 1b, 3b\n\n\t" \ 203 ".previous\n\t" \ 204 : "=r" (x) : "r" (__m(addr)), "i" (retval)) 205 206 extern int __get_user_bad(void); 207 208 extern void copy_from_user_overflow(void) 209 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 210 __compiletime_error("copy_from_user() buffer size is not provably correct") 211 #else 212 __compiletime_warning("copy_from_user() buffer size is not provably correct") 213 #endif 214 ; 215 216 extern unsigned long __must_check ___copy_from_user(void *to, 217 const void __user *from, 218 unsigned long size); 219 extern unsigned long copy_from_user_fixup(void *to, const void __user *from, 220 unsigned long size); 221 static inline unsigned long __must_check 222 copy_from_user(void *to, const void __user *from, unsigned long size) 223 { 224 unsigned long ret = (unsigned long) -EFAULT; 225 int sz = __compiletime_object_size(to); 226 227 if (likely(sz == -1 || sz >= size)) { 228 ret = ___copy_from_user(to, from, size); 229 if (unlikely(ret)) 230 ret = copy_from_user_fixup(to, from, size); 231 } else { 232 copy_from_user_overflow(); 233 } 234 return ret; 235 } 236 #define __copy_from_user copy_from_user 237 238 extern unsigned long __must_check ___copy_to_user(void __user *to, 239 const void *from, 240 unsigned long size); 241 extern unsigned long copy_to_user_fixup(void __user *to, const void *from, 242 unsigned long size); 243 static inline unsigned long __must_check 244 copy_to_user(void __user *to, const void *from, unsigned long size) 245 { 246 unsigned long ret = ___copy_to_user(to, from, size); 247 248 if (unlikely(ret)) 249 ret = copy_to_user_fixup(to, from, size); 250 return ret; 251 } 252 #define __copy_to_user copy_to_user 253 254 extern unsigned long __must_check ___copy_in_user(void __user *to, 255 const void __user *from, 256 unsigned long size); 257 extern unsigned long copy_in_user_fixup(void __user *to, void __user *from, 258 unsigned long size); 259 static inline unsigned long __must_check 260 copy_in_user(void __user *to, void __user *from, unsigned long size) 261 { 262 unsigned long ret = ___copy_in_user(to, from, size); 263 264 if (unlikely(ret)) 265 ret = copy_in_user_fixup(to, from, size); 266 return ret; 267 } 268 #define __copy_in_user copy_in_user 269 270 extern unsigned long __must_check __clear_user(void __user *, unsigned long); 271 272 #define clear_user __clear_user 273 274 extern long __must_check __strncpy_from_user(char *dest, const char __user *src, long count); 275 276 #define strncpy_from_user __strncpy_from_user 277 278 extern long __strlen_user(const char __user *); 279 extern long __strnlen_user(const char __user *, long len); 280 281 #define strlen_user __strlen_user 282 #define strnlen_user __strnlen_user 283 #define __copy_to_user_inatomic ___copy_to_user 284 #define __copy_from_user_inatomic ___copy_from_user 285 286 #endif /* __ASSEMBLY__ */ 287 288 #endif /* _ASM_UACCESS_H */ 289