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 /* 53 * Test whether a block of memory is a valid user space address. 54 * Returns 0 if the range is valid, nonzero otherwise. 55 */ 56 static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, unsigned long limit) 57 { 58 if (__builtin_constant_p(size)) 59 return addr > limit - size; 60 61 addr += size; 62 if (addr < size) 63 return true; 64 65 return addr > limit; 66 } 67 68 #define __range_not_ok(addr, size, limit) \ 69 ({ \ 70 __chk_user_ptr(addr); \ 71 __chk_range_not_ok((unsigned long __force)(addr), size, limit); \ 72 }) 73 74 static inline int __access_ok(const void __user * addr, unsigned long size) 75 { 76 return 1; 77 } 78 79 static inline int access_ok(int type, const void __user * addr, unsigned long size) 80 { 81 return 1; 82 } 83 84 /* 85 * The exception table consists of pairs of addresses: the first is the 86 * address of an instruction that is allowed to fault, and the second is 87 * the address at which the program should continue. No registers are 88 * modified, so it is entirely up to the continuation code to figure out 89 * what to do. 90 * 91 * All the routines below use bits of fixup code that are out of line 92 * with the main instruction path. This means when everything is well, 93 * we don't even have to jump over them. Further, they do not intrude 94 * on our cache or tlb entries. 95 */ 96 97 struct exception_table_entry { 98 unsigned int insn, fixup; 99 }; 100 101 void __ret_efault(void); 102 void __retl_efault(void); 103 104 /* Uh, these should become the main single-value transfer routines.. 105 * They automatically use the right size if we just have the right 106 * pointer type.. 107 * 108 * This gets kind of ugly. We want to return _two_ values in "get_user()" 109 * and yet we don't want to do any pointers, because that is too much 110 * of a performance impact. Thus we have a few rather ugly macros here, 111 * and hide all the ugliness from the user. 112 */ 113 #define put_user(x, ptr) ({ \ 114 unsigned long __pu_addr = (unsigned long)(ptr); \ 115 __chk_user_ptr(ptr); \ 116 __put_user_nocheck((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr)));\ 117 }) 118 119 #define get_user(x, ptr) ({ \ 120 unsigned long __gu_addr = (unsigned long)(ptr); \ 121 __chk_user_ptr(ptr); \ 122 __get_user_nocheck((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr)));\ 123 }) 124 125 #define __put_user(x, ptr) put_user(x, ptr) 126 #define __get_user(x, ptr) get_user(x, ptr) 127 128 struct __large_struct { unsigned long buf[100]; }; 129 #define __m(x) ((struct __large_struct *)(x)) 130 131 #define __put_user_nocheck(data, addr, size) ({ \ 132 register int __pu_ret; \ 133 switch (size) { \ 134 case 1: __put_user_asm(data, b, addr, __pu_ret); break; \ 135 case 2: __put_user_asm(data, h, addr, __pu_ret); break; \ 136 case 4: __put_user_asm(data, w, addr, __pu_ret); break; \ 137 case 8: __put_user_asm(data, x, addr, __pu_ret); break; \ 138 default: __pu_ret = __put_user_bad(); break; \ 139 } \ 140 __pu_ret; \ 141 }) 142 143 #define __put_user_asm(x, size, addr, ret) \ 144 __asm__ __volatile__( \ 145 "/* Put user asm, inline. */\n" \ 146 "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ 147 "clr %0\n" \ 148 "2:\n\n\t" \ 149 ".section .fixup,#alloc,#execinstr\n\t" \ 150 ".align 4\n" \ 151 "3:\n\t" \ 152 "sethi %%hi(2b), %0\n\t" \ 153 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 154 " mov %3, %0\n\n\t" \ 155 ".previous\n\t" \ 156 ".section __ex_table,\"a\"\n\t" \ 157 ".align 4\n\t" \ 158 ".word 1b, 3b\n\t" \ 159 ".previous\n\n\t" \ 160 : "=r" (ret) : "r" (x), "r" (__m(addr)), \ 161 "i" (-EFAULT)) 162 163 int __put_user_bad(void); 164 165 #define __get_user_nocheck(data, addr, size, type) ({ \ 166 register int __gu_ret; \ 167 register unsigned long __gu_val; \ 168 switch (size) { \ 169 case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \ 170 case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \ 171 case 4: __get_user_asm(__gu_val, uw, addr, __gu_ret); break; \ 172 case 8: __get_user_asm(__gu_val, x, addr, __gu_ret); break; \ 173 default: \ 174 __gu_val = 0; \ 175 __gu_ret = __get_user_bad(); \ 176 break; \ 177 } \ 178 data = (__force type) __gu_val; \ 179 __gu_ret; \ 180 }) 181 182 #define __get_user_asm(x, size, addr, ret) \ 183 __asm__ __volatile__( \ 184 "/* Get user asm, inline. */\n" \ 185 "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ 186 "clr %0\n" \ 187 "2:\n\n\t" \ 188 ".section .fixup,#alloc,#execinstr\n\t" \ 189 ".align 4\n" \ 190 "3:\n\t" \ 191 "sethi %%hi(2b), %0\n\t" \ 192 "clr %1\n\t" \ 193 "jmpl %0 + %%lo(2b), %%g0\n\t" \ 194 " mov %3, %0\n\n\t" \ 195 ".previous\n\t" \ 196 ".section __ex_table,\"a\"\n\t" \ 197 ".align 4\n\t" \ 198 ".word 1b, 3b\n\n\t" \ 199 ".previous\n\t" \ 200 : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ 201 "i" (-EFAULT)) 202 203 int __get_user_bad(void); 204 205 unsigned long __must_check ___copy_from_user(void *to, 206 const void __user *from, 207 unsigned long size); 208 unsigned long copy_from_user_fixup(void *to, const void __user *from, 209 unsigned long size); 210 static inline unsigned long __must_check 211 copy_from_user(void *to, const void __user *from, unsigned long size) 212 { 213 unsigned long ret = ___copy_from_user(to, from, size); 214 215 if (unlikely(ret)) 216 ret = copy_from_user_fixup(to, from, size); 217 218 return ret; 219 } 220 #define __copy_from_user copy_from_user 221 222 unsigned long __must_check ___copy_to_user(void __user *to, 223 const void *from, 224 unsigned long size); 225 unsigned long copy_to_user_fixup(void __user *to, const void *from, 226 unsigned long size); 227 static inline unsigned long __must_check 228 copy_to_user(void __user *to, const void *from, unsigned long size) 229 { 230 unsigned long ret = ___copy_to_user(to, from, size); 231 232 if (unlikely(ret)) 233 ret = copy_to_user_fixup(to, from, size); 234 return ret; 235 } 236 #define __copy_to_user copy_to_user 237 238 unsigned long __must_check ___copy_in_user(void __user *to, 239 const void __user *from, 240 unsigned long size); 241 unsigned long copy_in_user_fixup(void __user *to, void __user *from, 242 unsigned long size); 243 static inline unsigned long __must_check 244 copy_in_user(void __user *to, void __user *from, unsigned long size) 245 { 246 unsigned long ret = ___copy_in_user(to, from, size); 247 248 if (unlikely(ret)) 249 ret = copy_in_user_fixup(to, from, size); 250 return ret; 251 } 252 #define __copy_in_user copy_in_user 253 254 unsigned long __must_check __clear_user(void __user *, unsigned long); 255 256 #define clear_user __clear_user 257 258 __must_check long strlen_user(const char __user *str); 259 __must_check long strnlen_user(const char __user *str, long n); 260 261 #define __copy_to_user_inatomic __copy_to_user 262 #define __copy_from_user_inatomic __copy_from_user 263 264 struct pt_regs; 265 unsigned long compute_effective_address(struct pt_regs *, 266 unsigned int insn, 267 unsigned int rd); 268 269 #endif /* __ASSEMBLY__ */ 270 271 #endif /* _ASM_UACCESS_H */ 272