1 #ifndef __ASM_SH_UACCESS_H 2 #define __ASM_SH_UACCESS_H 3 4 #include <linux/errno.h> 5 #include <linux/sched.h> 6 #include <asm/segment.h> 7 8 #define VERIFY_READ 0 9 #define VERIFY_WRITE 1 10 11 #define __addr_ok(addr) \ 12 ((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg) 13 14 /* 15 * __access_ok: Check if address with size is OK or not. 16 * 17 * Uhhuh, this needs 33-bit arithmetic. We have a carry.. 18 * 19 * sum := addr + size; carry? --> flag = true; 20 * if (sum >= addr_limit) flag = true; 21 */ 22 #define __access_ok(addr, size) \ 23 (__addr_ok((addr) + (size))) 24 #define access_ok(type, addr, size) \ 25 (__chk_user_ptr(addr), \ 26 __access_ok((unsigned long __force)(addr), (size))) 27 28 /* 29 * Uh, these should become the main single-value transfer routines ... 30 * They automatically use the right size if we just have the right 31 * pointer type ... 32 * 33 * As SuperH uses the same address space for kernel and user data, we 34 * can just do these as direct assignments. 35 * 36 * Careful to not 37 * (a) re-use the arguments for side effects (sizeof is ok) 38 * (b) require any knowledge of processes at this stage 39 */ 40 #define put_user(x,ptr) __put_user_check((x), (ptr), sizeof(*(ptr))) 41 #define get_user(x,ptr) __get_user_check((x), (ptr), sizeof(*(ptr))) 42 43 /* 44 * The "__xxx" versions do not do address space checking, useful when 45 * doing multiple accesses to the same area (the user has to do the 46 * checks by hand with "access_ok()") 47 */ 48 #define __put_user(x,ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr))) 49 #define __get_user(x,ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr))) 50 51 struct __large_struct { unsigned long buf[100]; }; 52 #define __m(x) (*(struct __large_struct __user *)(x)) 53 54 #define __get_user_nocheck(x,ptr,size) \ 55 ({ \ 56 long __gu_err; \ 57 unsigned long __gu_val; \ 58 const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ 59 __chk_user_ptr(ptr); \ 60 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ 61 (x) = (__typeof__(*(ptr)))__gu_val; \ 62 __gu_err; \ 63 }) 64 65 #define __get_user_check(x,ptr,size) \ 66 ({ \ 67 long __gu_err = -EFAULT; \ 68 unsigned long __gu_val = 0; \ 69 const __typeof__(*(ptr)) *__gu_addr = (ptr); \ 70 if (likely(access_ok(VERIFY_READ, __gu_addr, (size)))) \ 71 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ 72 (x) = (__typeof__(*(ptr)))__gu_val; \ 73 __gu_err; \ 74 }) 75 76 #define __put_user_nocheck(x,ptr,size) \ 77 ({ \ 78 long __pu_err; \ 79 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ 80 __chk_user_ptr(ptr); \ 81 __put_user_size((x), __pu_addr, (size), __pu_err); \ 82 __pu_err; \ 83 }) 84 85 #define __put_user_check(x,ptr,size) \ 86 ({ \ 87 long __pu_err = -EFAULT; \ 88 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ 89 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \ 90 __put_user_size((x), __pu_addr, (size), \ 91 __pu_err); \ 92 __pu_err; \ 93 }) 94 95 #ifdef CONFIG_SUPERH32 96 # include "uaccess_32.h" 97 #else 98 # include "uaccess_64.h" 99 #endif 100 101 /* Generic arbitrary sized copy. */ 102 /* Return the number of bytes NOT copied */ 103 __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n); 104 105 static __always_inline unsigned long 106 __copy_from_user(void *to, const void __user *from, unsigned long n) 107 { 108 return __copy_user(to, (__force void *)from, n); 109 } 110 111 static __always_inline unsigned long __must_check 112 __copy_to_user(void __user *to, const void *from, unsigned long n) 113 { 114 return __copy_user((__force void *)to, from, n); 115 } 116 117 #define __copy_to_user_inatomic __copy_to_user 118 #define __copy_from_user_inatomic __copy_from_user 119 120 /* 121 * Clear the area and return remaining number of bytes 122 * (on failure. Usually it's 0.) 123 */ 124 __kernel_size_t __clear_user(void *addr, __kernel_size_t size); 125 126 #define clear_user(addr,n) \ 127 ({ \ 128 void __user * __cl_addr = (addr); \ 129 unsigned long __cl_size = (n); \ 130 \ 131 if (__cl_size && access_ok(VERIFY_WRITE, \ 132 ((unsigned long)(__cl_addr)), __cl_size)) \ 133 __cl_size = __clear_user(__cl_addr, __cl_size); \ 134 \ 135 __cl_size; \ 136 }) 137 138 /** 139 * strncpy_from_user: - Copy a NUL terminated string from userspace. 140 * @dst: Destination address, in kernel space. This buffer must be at 141 * least @count bytes long. 142 * @src: Source address, in user space. 143 * @count: Maximum number of bytes to copy, including the trailing NUL. 144 * 145 * Copies a NUL-terminated string from userspace to kernel space. 146 * 147 * On success, returns the length of the string (not including the trailing 148 * NUL). 149 * 150 * If access to userspace fails, returns -EFAULT (some data may have been 151 * copied). 152 * 153 * If @count is smaller than the length of the string, copies @count bytes 154 * and returns @count. 155 */ 156 #define strncpy_from_user(dest,src,count) \ 157 ({ \ 158 unsigned long __sfu_src = (unsigned long)(src); \ 159 int __sfu_count = (int)(count); \ 160 long __sfu_res = -EFAULT; \ 161 \ 162 if (__access_ok(__sfu_src, __sfu_count)) \ 163 __sfu_res = __strncpy_from_user((unsigned long)(dest), \ 164 __sfu_src, __sfu_count); \ 165 \ 166 __sfu_res; \ 167 }) 168 169 static inline unsigned long 170 copy_from_user(void *to, const void __user *from, unsigned long n) 171 { 172 unsigned long __copy_from = (unsigned long) from; 173 __kernel_size_t __copy_size = (__kernel_size_t) n; 174 175 if (__copy_size && __access_ok(__copy_from, __copy_size)) 176 return __copy_user(to, from, __copy_size); 177 178 return __copy_size; 179 } 180 181 static inline unsigned long 182 copy_to_user(void __user *to, const void *from, unsigned long n) 183 { 184 unsigned long __copy_to = (unsigned long) to; 185 __kernel_size_t __copy_size = (__kernel_size_t) n; 186 187 if (__copy_size && __access_ok(__copy_to, __copy_size)) 188 return __copy_user(to, from, __copy_size); 189 190 return __copy_size; 191 } 192 193 /** 194 * strnlen_user: - Get the size of a string in user space. 195 * @s: The string to measure. 196 * @n: The maximum valid length 197 * 198 * Context: User context only. This function may sleep. 199 * 200 * Get the size of a NUL-terminated string in user space. 201 * 202 * Returns the size of the string INCLUDING the terminating NUL. 203 * On exception, returns 0. 204 * If the string is too long, returns a value greater than @n. 205 */ 206 static inline long strnlen_user(const char __user *s, long n) 207 { 208 if (!__addr_ok(s)) 209 return 0; 210 else 211 return __strnlen_user(s, n); 212 } 213 214 /** 215 * strlen_user: - Get the size of a string in user space. 216 * @str: The string to measure. 217 * 218 * Context: User context only. This function may sleep. 219 * 220 * Get the size of a NUL-terminated string in user space. 221 * 222 * Returns the size of the string INCLUDING the terminating NUL. 223 * On exception, returns 0. 224 * 225 * If there is a limit on the length of a valid string, you may wish to 226 * consider using strnlen_user() instead. 227 */ 228 #define strlen_user(str) strnlen_user(str, ~0UL >> 1) 229 230 /* 231 * The exception table consists of pairs of addresses: the first is the 232 * address of an instruction that is allowed to fault, and the second is 233 * the address at which the program should continue. No registers are 234 * modified, so it is entirely up to the continuation code to figure out 235 * what to do. 236 * 237 * All the routines below use bits of fixup code that are out of line 238 * with the main instruction path. This means when everything is well, 239 * we don't even have to jump over them. Further, they do not intrude 240 * on our cache or tlb entries. 241 */ 242 struct exception_table_entry { 243 unsigned long insn, fixup; 244 }; 245 246 #if defined(CONFIG_SUPERH64) && defined(CONFIG_MMU) 247 #define ARCH_HAS_SEARCH_EXTABLE 248 #endif 249 250 int fixup_exception(struct pt_regs *regs); 251 /* Returns 0 if exception not found and fixup.unit otherwise. */ 252 unsigned long search_exception_table(unsigned long addr); 253 const struct exception_table_entry *search_exception_tables(unsigned long addr); 254 255 256 #endif /* __ASM_SH_UACCESS_H */ 257