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 extern void __ret_efault(void); 80 extern 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 #define get_user(x,ptr) ({ \ 97 unsigned long __gu_addr = (unsigned long)(ptr); \ 98 __chk_user_ptr(ptr); \ 99 __get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); }) 100 101 #define __put_user(x,ptr) put_user(x,ptr) 102 #define __get_user(x,ptr) get_user(x,ptr) 103 104 struct __large_struct { unsigned long buf[100]; }; 105 #define __m(x) ((struct __large_struct *)(x)) 106 107 #define __put_user_nocheck(data,addr,size) ({ \ 108 register int __pu_ret; \ 109 switch (size) { \ 110 case 1: __put_user_asm(data,b,addr,__pu_ret); break; \ 111 case 2: __put_user_asm(data,h,addr,__pu_ret); break; \ 112 case 4: __put_user_asm(data,w,addr,__pu_ret); break; \ 113 case 8: __put_user_asm(data,x,addr,__pu_ret); break; \ 114 default: __pu_ret = __put_user_bad(); break; \ 115 } __pu_ret; }) 116 117 #define __put_user_asm(x,size,addr,ret) \ 118 __asm__ __volatile__( \ 119 "/* Put user asm, inline. */\n" \ 120 "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ 121 "clr %0\n" \ 122 "2:\n\n\t" \ 123 ".section .fixup,#alloc,#execinstr\n\t" \ 124 ".align 4\n" \ 125 "3:\n\t" \ 126 "sethi %%hi(2b), %0\n\t" \ 127 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 128 " mov %3, %0\n\n\t" \ 129 ".previous\n\t" \ 130 ".section __ex_table,\"a\"\n\t" \ 131 ".align 4\n\t" \ 132 ".word 1b, 3b\n\t" \ 133 ".previous\n\n\t" \ 134 : "=r" (ret) : "r" (x), "r" (__m(addr)), \ 135 "i" (-EFAULT)) 136 137 extern int __put_user_bad(void); 138 139 #define __get_user_nocheck(data,addr,size,type) ({ \ 140 register int __gu_ret; \ 141 register unsigned long __gu_val; \ 142 switch (size) { \ 143 case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \ 144 case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \ 145 case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \ 146 case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \ 147 default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \ 148 } data = (type) __gu_val; __gu_ret; }) 149 150 #define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \ 151 register unsigned long __gu_val __asm__ ("l1"); \ 152 switch (size) { \ 153 case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \ 154 case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \ 155 case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \ 156 case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \ 157 default: if (__get_user_bad()) return retval; \ 158 } data = (type) __gu_val; }) 159 160 #define __get_user_asm(x,size,addr,ret) \ 161 __asm__ __volatile__( \ 162 "/* Get user asm, inline. */\n" \ 163 "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ 164 "clr %0\n" \ 165 "2:\n\n\t" \ 166 ".section .fixup,#alloc,#execinstr\n\t" \ 167 ".align 4\n" \ 168 "3:\n\t" \ 169 "sethi %%hi(2b), %0\n\t" \ 170 "clr %1\n\t" \ 171 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 172 " mov %3, %0\n\n\t" \ 173 ".previous\n\t" \ 174 ".section __ex_table,\"a\"\n\t" \ 175 ".align 4\n\t" \ 176 ".word 1b, 3b\n\n\t" \ 177 ".previous\n\t" \ 178 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ 179 "i" (-EFAULT)) 180 181 #define __get_user_asm_ret(x,size,addr,retval) \ 182 if (__builtin_constant_p(retval) && retval == -EFAULT) \ 183 __asm__ __volatile__( \ 184 "/* Get user asm ret, inline. */\n" \ 185 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 186 ".section __ex_table,\"a\"\n\t" \ 187 ".align 4\n\t" \ 188 ".word 1b,__ret_efault\n\n\t" \ 189 ".previous\n\t" \ 190 : "=r" (x) : "r" (__m(addr))); \ 191 else \ 192 __asm__ __volatile__( \ 193 "/* Get user asm ret, inline. */\n" \ 194 "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ 195 ".section .fixup,#alloc,#execinstr\n\t" \ 196 ".align 4\n" \ 197 "3:\n\t" \ 198 "ret\n\t" \ 199 " restore %%g0, %2, %%o0\n\n\t" \ 200 ".previous\n\t" \ 201 ".section __ex_table,\"a\"\n\t" \ 202 ".align 4\n\t" \ 203 ".word 1b, 3b\n\n\t" \ 204 ".previous\n\t" \ 205 : "=r" (x) : "r" (__m(addr)), "i" (retval)) 206 207 extern int __get_user_bad(void); 208 209 extern unsigned long __must_check ___copy_from_user(void *to, 210 const void __user *from, 211 unsigned long size); 212 extern unsigned long copy_from_user_fixup(void *to, const void __user *from, 213 unsigned long size); 214 static inline unsigned long __must_check 215 copy_from_user(void *to, const void __user *from, unsigned long size) 216 { 217 unsigned long ret = ___copy_from_user(to, from, size); 218 219 if (unlikely(ret)) 220 ret = copy_from_user_fixup(to, from, size); 221 222 return ret; 223 } 224 #define __copy_from_user copy_from_user 225 226 extern unsigned long __must_check ___copy_to_user(void __user *to, 227 const void *from, 228 unsigned long size); 229 extern unsigned long copy_to_user_fixup(void __user *to, const void *from, 230 unsigned long size); 231 static inline unsigned long __must_check 232 copy_to_user(void __user *to, const void *from, unsigned long size) 233 { 234 unsigned long ret = ___copy_to_user(to, from, size); 235 236 if (unlikely(ret)) 237 ret = copy_to_user_fixup(to, from, size); 238 return ret; 239 } 240 #define __copy_to_user copy_to_user 241 242 extern unsigned long __must_check ___copy_in_user(void __user *to, 243 const void __user *from, 244 unsigned long size); 245 extern unsigned long copy_in_user_fixup(void __user *to, void __user *from, 246 unsigned long size); 247 static inline unsigned long __must_check 248 copy_in_user(void __user *to, void __user *from, unsigned long size) 249 { 250 unsigned long ret = ___copy_in_user(to, from, size); 251 252 if (unlikely(ret)) 253 ret = copy_in_user_fixup(to, from, size); 254 return ret; 255 } 256 #define __copy_in_user copy_in_user 257 258 extern unsigned long __must_check __clear_user(void __user *, unsigned long); 259 260 #define clear_user __clear_user 261 262 extern __must_check long strlen_user(const char __user *str); 263 extern __must_check long strnlen_user(const char __user *str, long n); 264 265 #define __copy_to_user_inatomic ___copy_to_user 266 #define __copy_from_user_inatomic ___copy_from_user 267 268 struct pt_regs; 269 extern unsigned long compute_effective_address(struct pt_regs *, 270 unsigned int insn, 271 unsigned int rd); 272 273 #endif /* __ASSEMBLY__ */ 274 275 #endif /* _ASM_UACCESS_H */ 276