1 #ifndef __PARISC_UACCESS_H 2 #define __PARISC_UACCESS_H 3 4 /* 5 * User space memory access functions 6 */ 7 #include <asm/page.h> 8 #include <asm/cache.h> 9 #include <asm/errno.h> 10 #include <asm-generic/uaccess-unaligned.h> 11 12 #include <linux/bug.h> 13 14 #define VERIFY_READ 0 15 #define VERIFY_WRITE 1 16 17 #define KERNEL_DS ((mm_segment_t){0}) 18 #define USER_DS ((mm_segment_t){1}) 19 20 #define segment_eq(a,b) ((a).seg == (b).seg) 21 22 #define get_ds() (KERNEL_DS) 23 #define get_fs() (current_thread_info()->addr_limit) 24 #define set_fs(x) (current_thread_info()->addr_limit = (x)) 25 26 /* 27 * Note that since kernel addresses are in a separate address space on 28 * parisc, we don't need to do anything for access_ok(). 29 * We just let the page fault handler do the right thing. This also means 30 * that put_user is the same as __put_user, etc. 31 */ 32 33 static inline long access_ok(int type, const void __user * addr, 34 unsigned long size) 35 { 36 return 1; 37 } 38 39 #define put_user __put_user 40 #define get_user __get_user 41 42 #if !defined(CONFIG_64BIT) 43 #define LDD_KERNEL(ptr) BUILD_BUG() 44 #define LDD_USER(ptr) BUILD_BUG() 45 #define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr) 46 #define STD_USER(x, ptr) __put_user_asm64(x,ptr) 47 #define ASM_WORD_INSN ".word\t" 48 #else 49 #define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr) 50 #define LDD_USER(ptr) __get_user_asm("ldd",ptr) 51 #define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr) 52 #define STD_USER(x, ptr) __put_user_asm("std",x,ptr) 53 #define ASM_WORD_INSN ".dword\t" 54 #endif 55 56 /* 57 * The exception table contains two values: the first is an address 58 * for an instruction that is allowed to fault, and the second is 59 * the address to the fixup routine. Even on a 64bit kernel we could 60 * use a 32bit (unsigned int) address here. 61 */ 62 63 struct exception_table_entry { 64 unsigned long insn; /* address of insn that is allowed to fault. */ 65 unsigned long fixup; /* fixup routine */ 66 }; 67 68 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ 69 ".section __ex_table,\"aw\"\n" \ 70 ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \ 71 ".previous\n" 72 73 /* 74 * The page fault handler stores, in a per-cpu area, the following information 75 * if a fixup routine is available. 76 */ 77 struct exception_data { 78 unsigned long fault_ip; 79 unsigned long fault_space; 80 unsigned long fault_addr; 81 }; 82 83 #define __get_user(x,ptr) \ 84 ({ \ 85 register long __gu_err __asm__ ("r8") = 0; \ 86 register long __gu_val __asm__ ("r9") = 0; \ 87 \ 88 if (segment_eq(get_fs(),KERNEL_DS)) { \ 89 switch (sizeof(*(ptr))) { \ 90 case 1: __get_kernel_asm("ldb",ptr); break; \ 91 case 2: __get_kernel_asm("ldh",ptr); break; \ 92 case 4: __get_kernel_asm("ldw",ptr); break; \ 93 case 8: LDD_KERNEL(ptr); break; \ 94 default: BUILD_BUG(); break; \ 95 } \ 96 } \ 97 else { \ 98 switch (sizeof(*(ptr))) { \ 99 case 1: __get_user_asm("ldb",ptr); break; \ 100 case 2: __get_user_asm("ldh",ptr); break; \ 101 case 4: __get_user_asm("ldw",ptr); break; \ 102 case 8: LDD_USER(ptr); break; \ 103 default: BUILD_BUG(); break; \ 104 } \ 105 } \ 106 \ 107 (x) = (__typeof__(*(ptr))) __gu_val; \ 108 __gu_err; \ 109 }) 110 111 #define __get_kernel_asm(ldx,ptr) \ 112 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \ 113 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ 114 : "=r"(__gu_val), "=r"(__gu_err) \ 115 : "r"(ptr), "1"(__gu_err) \ 116 : "r1"); 117 118 #define __get_user_asm(ldx,ptr) \ 119 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \ 120 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\ 121 : "=r"(__gu_val), "=r"(__gu_err) \ 122 : "r"(ptr), "1"(__gu_err) \ 123 : "r1"); 124 125 #define __put_user(x,ptr) \ 126 ({ \ 127 register long __pu_err __asm__ ("r8") = 0; \ 128 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \ 129 \ 130 if (segment_eq(get_fs(),KERNEL_DS)) { \ 131 switch (sizeof(*(ptr))) { \ 132 case 1: __put_kernel_asm("stb",__x,ptr); break; \ 133 case 2: __put_kernel_asm("sth",__x,ptr); break; \ 134 case 4: __put_kernel_asm("stw",__x,ptr); break; \ 135 case 8: STD_KERNEL(__x,ptr); break; \ 136 default: BUILD_BUG(); break; \ 137 } \ 138 } \ 139 else { \ 140 switch (sizeof(*(ptr))) { \ 141 case 1: __put_user_asm("stb",__x,ptr); break; \ 142 case 2: __put_user_asm("sth",__x,ptr); break; \ 143 case 4: __put_user_asm("stw",__x,ptr); break; \ 144 case 8: STD_USER(__x,ptr); break; \ 145 default: BUILD_BUG(); break; \ 146 } \ 147 } \ 148 \ 149 __pu_err; \ 150 }) 151 152 /* 153 * The "__put_user/kernel_asm()" macros tell gcc they read from memory 154 * instead of writing. This is because they do not write to any memory 155 * gcc knows about, so there are no aliasing issues. These macros must 156 * also be aware that "fixup_put_user_skip_[12]" are executed in the 157 * context of the fault, and any registers used there must be listed 158 * as clobbers. In this case only "r1" is used by the current routines. 159 * r8/r9 are already listed as err/val. 160 */ 161 162 #define __put_kernel_asm(stx,x,ptr) \ 163 __asm__ __volatile__ ( \ 164 "\n1:\t" stx "\t%2,0(%1)\n\t" \ 165 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\ 166 : "=r"(__pu_err) \ 167 : "r"(ptr), "r"(x), "0"(__pu_err) \ 168 : "r1") 169 170 #define __put_user_asm(stx,x,ptr) \ 171 __asm__ __volatile__ ( \ 172 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \ 173 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\ 174 : "=r"(__pu_err) \ 175 : "r"(ptr), "r"(x), "0"(__pu_err) \ 176 : "r1") 177 178 179 #if !defined(CONFIG_64BIT) 180 181 #define __put_kernel_asm64(__val,ptr) do { \ 182 __asm__ __volatile__ ( \ 183 "\n1:\tstw %2,0(%1)" \ 184 "\n2:\tstw %R2,4(%1)\n\t" \ 185 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ 186 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ 187 : "=r"(__pu_err) \ 188 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 189 : "r1"); \ 190 } while (0) 191 192 #define __put_user_asm64(__val,ptr) do { \ 193 __asm__ __volatile__ ( \ 194 "\n1:\tstw %2,0(%%sr3,%1)" \ 195 "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \ 196 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ 197 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ 198 : "=r"(__pu_err) \ 199 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 200 : "r1"); \ 201 } while (0) 202 203 #endif /* !defined(CONFIG_64BIT) */ 204 205 206 /* 207 * Complex access routines -- external declarations 208 */ 209 210 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long); 211 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long); 212 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long); 213 extern long strncpy_from_user(char *, const char __user *, long); 214 extern unsigned lclear_user(void __user *,unsigned long); 215 extern long lstrnlen_user(const char __user *,long); 216 /* 217 * Complex access routines -- macros 218 */ 219 #define user_addr_max() (~0UL) 220 221 #define strnlen_user lstrnlen_user 222 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL) 223 #define clear_user lclear_user 224 #define __clear_user lclear_user 225 226 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len); 227 #define __copy_to_user copy_to_user 228 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len); 229 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len); 230 #define __copy_in_user copy_in_user 231 #define __copy_to_user_inatomic __copy_to_user 232 #define __copy_from_user_inatomic __copy_from_user 233 234 extern void copy_from_user_overflow(void) 235 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 236 __compiletime_error("copy_from_user() buffer size is not provably correct") 237 #else 238 __compiletime_warning("copy_from_user() buffer size is not provably correct") 239 #endif 240 ; 241 242 static inline unsigned long __must_check copy_from_user(void *to, 243 const void __user *from, 244 unsigned long n) 245 { 246 int sz = __compiletime_object_size(to); 247 int ret = -EFAULT; 248 249 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n)) 250 ret = __copy_from_user(to, from, n); 251 else 252 copy_from_user_overflow(); 253 254 return ret; 255 } 256 257 struct pt_regs; 258 int fixup_exception(struct pt_regs *regs); 259 260 #endif /* __PARISC_UACCESS_H */ 261