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/compiler.h> 10 #include <linux/string.h> 11 #include <linux/thread_info.h> 12 #include <asm/asi.h> 13 #include <asm/system.h> 14 #include <asm/spitfire.h> 15 #include <asm-generic/uaccess-unaligned.h> 16 #endif 17 18 #ifndef __ASSEMBLY__ 19 20 /* 21 * Sparc64 is segmented, though more like the M68K than the I386. 22 * We use the secondary ASI to address user memory, which references a 23 * completely different VM map, thus there is zero chance of the user 24 * doing something queer and tricking us into poking kernel memory. 25 * 26 * What is left here is basically what is needed for the other parts of 27 * the kernel that expect to be able to manipulate, erum, "segments". 28 * Or perhaps more properly, permissions. 29 * 30 * "For historical reasons, these macros are grossly misnamed." -Linus 31 */ 32 33 #define KERNEL_DS ((mm_segment_t) { ASI_P }) 34 #define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */ 35 36 #define VERIFY_READ 0 37 #define VERIFY_WRITE 1 38 39 #define get_fs() ((mm_segment_t) { get_thread_current_ds() }) 40 #define get_ds() (KERNEL_DS) 41 42 #define segment_eq(a,b) ((a).seg == (b).seg) 43 44 #define set_fs(val) \ 45 do { \ 46 set_thread_current_ds((val).seg); \ 47 __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ 48 } while(0) 49 50 static inline int __access_ok(const void __user * addr, unsigned long size) 51 { 52 return 1; 53 } 54 55 static inline int access_ok(int type, const void __user * addr, unsigned long size) 56 { 57 return 1; 58 } 59 60 /* 61 * The exception table consists of pairs of addresses: the first is the 62 * address of an instruction that is allowed to fault, and the second is 63 * the address at which the program should continue. No registers are 64 * modified, so it is entirely up to the continuation code to figure out 65 * what to do. 66 * 67 * All the routines below use bits of fixup code that are out of line 68 * with the main instruction path. This means when everything is well, 69 * we don't even have to jump over them. Further, they do not intrude 70 * on our cache or tlb entries. 71 */ 72 73 struct exception_table_entry { 74 unsigned int insn, fixup; 75 }; 76 77 extern void __ret_efault(void); 78 extern void __retl_efault(void); 79 80 /* Uh, these should become the main single-value transfer routines.. 81 * They automatically use the right size if we just have the right 82 * pointer type.. 83 * 84 * This gets kind of ugly. We want to return _two_ values in "get_user()" 85 * and yet we don't want to do any pointers, because that is too much 86 * of a performance impact. Thus we have a few rather ugly macros here, 87 * and hide all the ugliness from the user. 88 */ 89 #define put_user(x,ptr) ({ \ 90 unsigned long __pu_addr = (unsigned long)(ptr); \ 91 __chk_user_ptr(ptr); \ 92 __put_user_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); }) 93 94 #define get_user(x,ptr) ({ \ 95 unsigned long __gu_addr = (unsigned long)(ptr); \ 96 __chk_user_ptr(ptr); \ 97 __get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); }) 98 99 #define __put_user(x,ptr) put_user(x,ptr) 100 #define __get_user(x,ptr) get_user(x,ptr) 101 102 struct __large_struct { unsigned long buf[100]; }; 103 #define __m(x) ((struct __large_struct *)(x)) 104 105 #define __put_user_nocheck(data,addr,size) ({ \ 106 register int __pu_ret; \ 107 switch (size) { \ 108 case 1: __put_user_asm(data,b,addr,__pu_ret); break; \ 109 case 2: __put_user_asm(data,h,addr,__pu_ret); break; \ 110 case 4: __put_user_asm(data,w,addr,__pu_ret); break; \ 111 case 8: __put_user_asm(data,x,addr,__pu_ret); break; \ 112 default: __pu_ret = __put_user_bad(); break; \ 113 } __pu_ret; }) 114 115 #define __put_user_asm(x,size,addr,ret) \ 116 __asm__ __volatile__( \ 117 "/* Put user asm, inline. */\n" \ 118 "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ 119 "clr %0\n" \ 120 "2:\n\n\t" \ 121 ".section .fixup,#alloc,#execinstr\n\t" \ 122 ".align 4\n" \ 123 "3:\n\t" \ 124 "sethi %%hi(2b), %0\n\t" \ 125 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 126 " mov %3, %0\n\n\t" \ 127 ".previous\n\t" \ 128 ".section __ex_table,\"a\"\n\t" \ 129 ".align 4\n\t" \ 130 ".word 1b, 3b\n\t" \ 131 ".previous\n\n\t" \ 132 : "=r" (ret) : "r" (x), "r" (__m(addr)), \ 133 "i" (-EFAULT)) 134 135 extern int __put_user_bad(void); 136 137 #define __get_user_nocheck(data,addr,size,type) ({ \ 138 register int __gu_ret; \ 139 register unsigned long __gu_val; \ 140 switch (size) { \ 141 case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \ 142 case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \ 143 case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \ 144 case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \ 145 default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \ 146 } data = (type) __gu_val; __gu_ret; }) 147 148 #define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \ 149 register unsigned long __gu_val __asm__ ("l1"); \ 150 switch (size) { \ 151 case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \ 152 case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \ 153 case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \ 154 case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \ 155 default: if (__get_user_bad()) return retval; \ 156 } data = (type) __gu_val; }) 157 158 #define __get_user_asm(x,size,addr,ret) \ 159 __asm__ __volatile__( \ 160 "/* Get user asm, inline. */\n" \ 161 "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ 162 "clr %0\n" \ 163 "2:\n\n\t" \ 164 ".section .fixup,#alloc,#execinstr\n\t" \ 165 ".align 4\n" \ 166 "3:\n\t" \ 167 "sethi %%hi(2b), %0\n\t" \ 168 "clr %1\n\t" \ 169 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 170 " mov %3, %0\n\n\t" \ 171 ".previous\n\t" \ 172 ".section __ex_table,\"a\"\n\t" \ 173 ".align 4\n\t" \ 174 ".word 1b, 3b\n\n\t" \ 175 ".previous\n\t" \ 176 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ 177 "i" (-EFAULT)) 178 179 #define __get_user_asm_ret(x,size,addr,retval) \ 180 if (__builtin_constant_p(retval) && retval == -EFAULT) \ 181 __asm__ __volatile__( \ 182 "/* Get user asm ret, inline. */\n" \ 183 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 184 ".section __ex_table,\"a\"\n\t" \ 185 ".align 4\n\t" \ 186 ".word 1b,__ret_efault\n\n\t" \ 187 ".previous\n\t" \ 188 : "=r" (x) : "r" (__m(addr))); \ 189 else \ 190 __asm__ __volatile__( \ 191 "/* Get user asm ret, inline. */\n" \ 192 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 193 ".section .fixup,#alloc,#execinstr\n\t" \ 194 ".align 4\n" \ 195 "3:\n\t" \ 196 "ret\n\t" \ 197 " restore %%g0, %2, %%o0\n\n\t" \ 198 ".previous\n\t" \ 199 ".section __ex_table,\"a\"\n\t" \ 200 ".align 4\n\t" \ 201 ".word 1b, 3b\n\n\t" \ 202 ".previous\n\t" \ 203 : "=r" (x) : "r" (__m(addr)), "i" (retval)) 204 205 extern int __get_user_bad(void); 206 207 extern unsigned long __must_check ___copy_from_user(void *to, 208 const void __user *from, 209 unsigned long size); 210 extern unsigned long copy_from_user_fixup(void *to, const void __user *from, 211 unsigned long size); 212 static inline unsigned long __must_check 213 copy_from_user(void *to, const void __user *from, unsigned long size) 214 { 215 unsigned long ret = ___copy_from_user(to, from, size); 216 217 if (unlikely(ret)) 218 ret = copy_from_user_fixup(to, from, size); 219 return ret; 220 } 221 #define __copy_from_user copy_from_user 222 223 extern unsigned long __must_check ___copy_to_user(void __user *to, 224 const void *from, 225 unsigned long size); 226 extern unsigned long copy_to_user_fixup(void __user *to, const void *from, 227 unsigned long size); 228 static inline unsigned long __must_check 229 copy_to_user(void __user *to, const void *from, unsigned long size) 230 { 231 unsigned long ret = ___copy_to_user(to, from, size); 232 233 if (unlikely(ret)) 234 ret = copy_to_user_fixup(to, from, size); 235 return ret; 236 } 237 #define __copy_to_user copy_to_user 238 239 extern unsigned long __must_check ___copy_in_user(void __user *to, 240 const void __user *from, 241 unsigned long size); 242 extern unsigned long copy_in_user_fixup(void __user *to, void __user *from, 243 unsigned long size); 244 static inline unsigned long __must_check 245 copy_in_user(void __user *to, void __user *from, unsigned long size) 246 { 247 unsigned long ret = ___copy_in_user(to, from, size); 248 249 if (unlikely(ret)) 250 ret = copy_in_user_fixup(to, from, size); 251 return ret; 252 } 253 #define __copy_in_user copy_in_user 254 255 extern unsigned long __must_check __clear_user(void __user *, unsigned long); 256 257 #define clear_user __clear_user 258 259 extern long __must_check __strncpy_from_user(char *dest, const char __user *src, long count); 260 261 #define strncpy_from_user __strncpy_from_user 262 263 extern long __strlen_user(const char __user *); 264 extern long __strnlen_user(const char __user *, long len); 265 266 #define strlen_user __strlen_user 267 #define strnlen_user __strnlen_user 268 #define __copy_to_user_inatomic ___copy_to_user 269 #define __copy_from_user_inatomic ___copy_from_user 270 271 #endif /* __ASSEMBLY__ */ 272 273 #endif /* _ASM_UACCESS_H */ 274