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 51struct __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 __typeof__(*(ptr)) __pu_val = x; \ 81 __chk_user_ptr(ptr); \ 82 __put_user_size(__pu_val, __pu_addr, (size), __pu_err); \ 83 __pu_err; \ 84}) 85 86#define __put_user_check(x,ptr,size) \ 87({ \ 88 long __pu_err = -EFAULT; \ 89 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ 90 __typeof__(*(ptr)) __pu_val = x; \ 91 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \ 92 __put_user_size(__pu_val, __pu_addr, (size), \ 93 __pu_err); \ 94 __pu_err; \ 95}) 96 97#ifdef CONFIG_SUPERH32 98# include "uaccess_32.h" 99#else 100# include "uaccess_64.h" 101#endif 102 103/* Generic arbitrary sized copy. */ 104/* Return the number of bytes NOT copied */ 105__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n); 106 107static __always_inline unsigned long 108__copy_from_user(void *to, const void __user *from, unsigned long n) 109{ 110 return __copy_user(to, (__force void *)from, n); 111} 112 113static __always_inline unsigned long __must_check 114__copy_to_user(void __user *to, const void *from, unsigned long n) 115{ 116 return __copy_user((__force void *)to, from, n); 117} 118 119#define __copy_to_user_inatomic __copy_to_user 120#define __copy_from_user_inatomic __copy_from_user 121 122/* 123 * Clear the area and return remaining number of bytes 124 * (on failure. Usually it's 0.) 125 */ 126__kernel_size_t __clear_user(void *addr, __kernel_size_t size); 127 128#define clear_user(addr,n) \ 129({ \ 130 void __user * __cl_addr = (addr); \ 131 unsigned long __cl_size = (n); \ 132 \ 133 if (__cl_size && access_ok(VERIFY_WRITE, \ 134 ((unsigned long)(__cl_addr)), __cl_size)) \ 135 __cl_size = __clear_user(__cl_addr, __cl_size); \ 136 \ 137 __cl_size; \ 138}) 139 140/** 141 * strncpy_from_user: - Copy a NUL terminated string from userspace. 142 * @dst: Destination address, in kernel space. This buffer must be at 143 * least @count bytes long. 144 * @src: Source address, in user space. 145 * @count: Maximum number of bytes to copy, including the trailing NUL. 146 * 147 * Copies a NUL-terminated string from userspace to kernel space. 148 * 149 * On success, returns the length of the string (not including the trailing 150 * NUL). 151 * 152 * If access to userspace fails, returns -EFAULT (some data may have been 153 * copied). 154 * 155 * If @count is smaller than the length of the string, copies @count bytes 156 * and returns @count. 157 */ 158#define strncpy_from_user(dest,src,count) \ 159({ \ 160 unsigned long __sfu_src = (unsigned long)(src); \ 161 int __sfu_count = (int)(count); \ 162 long __sfu_res = -EFAULT; \ 163 \ 164 if (__access_ok(__sfu_src, __sfu_count)) \ 165 __sfu_res = __strncpy_from_user((unsigned long)(dest), \ 166 __sfu_src, __sfu_count); \ 167 \ 168 __sfu_res; \ 169}) 170 171static inline unsigned long 172copy_from_user(void *to, const void __user *from, unsigned long n) 173{ 174 unsigned long __copy_from = (unsigned long) from; 175 __kernel_size_t __copy_size = (__kernel_size_t) n; 176 177 if (__copy_size && __access_ok(__copy_from, __copy_size)) 178 return __copy_user(to, from, __copy_size); 179 180 return __copy_size; 181} 182 183static inline unsigned long 184copy_to_user(void __user *to, const void *from, unsigned long n) 185{ 186 unsigned long __copy_to = (unsigned long) to; 187 __kernel_size_t __copy_size = (__kernel_size_t) n; 188 189 if (__copy_size && __access_ok(__copy_to, __copy_size)) 190 return __copy_user(to, from, __copy_size); 191 192 return __copy_size; 193} 194 195/** 196 * strnlen_user: - Get the size of a string in user space. 197 * @s: The string to measure. 198 * @n: The maximum valid length 199 * 200 * Context: User context only. This function may sleep. 201 * 202 * Get the size of a NUL-terminated string in user space. 203 * 204 * Returns the size of the string INCLUDING the terminating NUL. 205 * On exception, returns 0. 206 * If the string is too long, returns a value greater than @n. 207 */ 208static inline long strnlen_user(const char __user *s, long n) 209{ 210 if (!__addr_ok(s)) 211 return 0; 212 else 213 return __strnlen_user(s, n); 214} 215 216/** 217 * strlen_user: - Get the size of a string in user space. 218 * @str: The string to measure. 219 * 220 * Context: User context only. This function may sleep. 221 * 222 * Get the size of a NUL-terminated string in user space. 223 * 224 * Returns the size of the string INCLUDING the terminating NUL. 225 * On exception, returns 0. 226 * 227 * If there is a limit on the length of a valid string, you may wish to 228 * consider using strnlen_user() instead. 229 */ 230#define strlen_user(str) strnlen_user(str, ~0UL >> 1) 231 232/* 233 * The exception table consists of pairs of addresses: the first is the 234 * address of an instruction that is allowed to fault, and the second is 235 * the address at which the program should continue. No registers are 236 * modified, so it is entirely up to the continuation code to figure out 237 * what to do. 238 * 239 * All the routines below use bits of fixup code that are out of line 240 * with the main instruction path. This means when everything is well, 241 * we don't even have to jump over them. Further, they do not intrude 242 * on our cache or tlb entries. 243 */ 244struct exception_table_entry { 245 unsigned long insn, fixup; 246}; 247 248#if defined(CONFIG_SUPERH64) && defined(CONFIG_MMU) 249#define ARCH_HAS_SEARCH_EXTABLE 250#endif 251 252int fixup_exception(struct pt_regs *regs); 253/* Returns 0 if exception not found and fixup.unit otherwise. */ 254unsigned long search_exception_table(unsigned long addr); 255const struct exception_table_entry *search_exception_tables(unsigned long addr); 256 257 258#endif /* __ASM_SH_UACCESS_H */ 259