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 #define ARCH_HAS_RELATIVE_EXTABLE 64 struct exception_table_entry { 65 int insn; /* relative address of insn that is allowed to fault. */ 66 int fixup; /* relative address of fixup routine */ 67 }; 68 69 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ 70 ".section __ex_table,\"aw\"\n" \ 71 ".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \ 72 ".previous\n" 73 74 /* 75 * The page fault handler stores, in a per-cpu area, the following information 76 * if a fixup routine is available. 77 */ 78 struct exception_data { 79 unsigned long fault_ip; 80 unsigned long fault_space; 81 unsigned long fault_addr; 82 }; 83 84 #define __get_user(x, ptr) \ 85 ({ \ 86 register long __gu_err __asm__ ("r8") = 0; \ 87 register long __gu_val __asm__ ("r9") = 0; \ 88 \ 89 if (segment_eq(get_fs(), KERNEL_DS)) { \ 90 switch (sizeof(*(ptr))) { \ 91 case 1: __get_kernel_asm("ldb", ptr); break; \ 92 case 2: __get_kernel_asm("ldh", ptr); break; \ 93 case 4: __get_kernel_asm("ldw", ptr); break; \ 94 case 8: LDD_KERNEL(ptr); break; \ 95 default: BUILD_BUG(); break; \ 96 } \ 97 } \ 98 else { \ 99 switch (sizeof(*(ptr))) { \ 100 case 1: __get_user_asm("ldb", ptr); break; \ 101 case 2: __get_user_asm("ldh", ptr); break; \ 102 case 4: __get_user_asm("ldw", ptr); break; \ 103 case 8: LDD_USER(ptr); break; \ 104 default: BUILD_BUG(); break; \ 105 } \ 106 } \ 107 \ 108 (x) = (__force __typeof__(*(ptr))) __gu_val; \ 109 __gu_err; \ 110 }) 111 112 #define __get_kernel_asm(ldx, ptr) \ 113 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \ 114 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ 115 : "=r"(__gu_val), "=r"(__gu_err) \ 116 : "r"(ptr), "1"(__gu_err) \ 117 : "r1"); 118 119 #define __get_user_asm(ldx, ptr) \ 120 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \ 121 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ 122 : "=r"(__gu_val), "=r"(__gu_err) \ 123 : "r"(ptr), "1"(__gu_err) \ 124 : "r1"); 125 126 #define __put_user(x, ptr) \ 127 ({ \ 128 register long __pu_err __asm__ ("r8") = 0; \ 129 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \ 130 \ 131 if (segment_eq(get_fs(), KERNEL_DS)) { \ 132 switch (sizeof(*(ptr))) { \ 133 case 1: __put_kernel_asm("stb", __x, ptr); break; \ 134 case 2: __put_kernel_asm("sth", __x, ptr); break; \ 135 case 4: __put_kernel_asm("stw", __x, ptr); break; \ 136 case 8: STD_KERNEL(__x, ptr); break; \ 137 default: BUILD_BUG(); break; \ 138 } \ 139 } \ 140 else { \ 141 switch (sizeof(*(ptr))) { \ 142 case 1: __put_user_asm("stb", __x, ptr); break; \ 143 case 2: __put_user_asm("sth", __x, ptr); break; \ 144 case 4: __put_user_asm("stw", __x, ptr); break; \ 145 case 8: STD_USER(__x, ptr); break; \ 146 default: BUILD_BUG(); break; \ 147 } \ 148 } \ 149 \ 150 __pu_err; \ 151 }) 152 153 /* 154 * The "__put_user/kernel_asm()" macros tell gcc they read from memory 155 * instead of writing. This is because they do not write to any memory 156 * gcc knows about, so there are no aliasing issues. These macros must 157 * also be aware that "fixup_put_user_skip_[12]" are executed in the 158 * context of the fault, and any registers used there must be listed 159 * as clobbers. In this case only "r1" is used by the current routines. 160 * r8/r9 are already listed as err/val. 161 */ 162 163 #define __put_kernel_asm(stx, x, ptr) \ 164 __asm__ __volatile__ ( \ 165 "\n1:\t" stx "\t%2,0(%1)\n\t" \ 166 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\ 167 : "=r"(__pu_err) \ 168 : "r"(ptr), "r"(x), "0"(__pu_err) \ 169 : "r1") 170 171 #define __put_user_asm(stx, x, ptr) \ 172 __asm__ __volatile__ ( \ 173 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \ 174 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\ 175 : "=r"(__pu_err) \ 176 : "r"(ptr), "r"(x), "0"(__pu_err) \ 177 : "r1") 178 179 180 #if !defined(CONFIG_64BIT) 181 182 #define __put_kernel_asm64(__val, ptr) do { \ 183 __asm__ __volatile__ ( \ 184 "\n1:\tstw %2,0(%1)" \ 185 "\n2:\tstw %R2,4(%1)\n\t" \ 186 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\ 187 ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\ 188 : "=r"(__pu_err) \ 189 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 190 : "r1"); \ 191 } while (0) 192 193 #define __put_user_asm64(__val, ptr) do { \ 194 __asm__ __volatile__ ( \ 195 "\n1:\tstw %2,0(%%sr3,%1)" \ 196 "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \ 197 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\ 198 ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\ 199 : "=r"(__pu_err) \ 200 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 201 : "r1"); \ 202 } while (0) 203 204 #endif /* !defined(CONFIG_64BIT) */ 205 206 207 /* 208 * Complex access routines -- external declarations 209 */ 210 211 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long); 212 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long); 213 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long); 214 extern long strncpy_from_user(char *, const char __user *, long); 215 extern unsigned lclear_user(void __user *, unsigned long); 216 extern long lstrnlen_user(const char __user *, long); 217 /* 218 * Complex access routines -- macros 219 */ 220 #define user_addr_max() (~0UL) 221 222 #define strnlen_user lstrnlen_user 223 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL) 224 #define clear_user lclear_user 225 #define __clear_user lclear_user 226 227 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len); 228 #define __copy_to_user copy_to_user 229 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len); 230 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len); 231 #define __copy_in_user copy_in_user 232 #define __copy_to_user_inatomic __copy_to_user 233 #define __copy_from_user_inatomic __copy_from_user 234 235 extern void copy_from_user_overflow(void) 236 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 237 __compiletime_error("copy_from_user() buffer size is not provably correct") 238 #else 239 __compiletime_warning("copy_from_user() buffer size is not provably correct") 240 #endif 241 ; 242 243 static inline unsigned long __must_check copy_from_user(void *to, 244 const void __user *from, 245 unsigned long n) 246 { 247 int sz = __compiletime_object_size(to); 248 int ret = -EFAULT; 249 250 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n)) 251 ret = __copy_from_user(to, from, n); 252 else 253 copy_from_user_overflow(); 254 255 return ret; 256 } 257 258 struct pt_regs; 259 int fixup_exception(struct pt_regs *regs); 260 261 #endif /* __PARISC_UACCESS_H */ 262