1 #ifndef __PARISC_UACCESS_H 2 #define __PARISC_UACCESS_H 3 4 /* 5 * User space memory access functions 6 */ 7 #include <asm/processor.h> 8 #include <asm/page.h> 9 #include <asm/cache.h> 10 #include <asm/errno.h> 11 #include <asm-generic/uaccess-unaligned.h> 12 13 #include <linux/sched.h> 14 15 #define VERIFY_READ 0 16 #define VERIFY_WRITE 1 17 18 #define KERNEL_DS ((mm_segment_t){0}) 19 #define USER_DS ((mm_segment_t){1}) 20 21 #define segment_eq(a,b) ((a).seg == (b).seg) 22 23 #define get_ds() (KERNEL_DS) 24 #define get_fs() (current_thread_info()->addr_limit) 25 #define set_fs(x) (current_thread_info()->addr_limit = (x)) 26 27 /* 28 * Note that since kernel addresses are in a separate address space on 29 * parisc, we don't need to do anything for access_ok(). 30 * We just let the page fault handler do the right thing. This also means 31 * that put_user is the same as __put_user, etc. 32 */ 33 34 extern int __get_kernel_bad(void); 35 extern int __get_user_bad(void); 36 extern int __put_kernel_bad(void); 37 extern int __put_user_bad(void); 38 39 40 /* 41 * Test whether a block of memory is a valid user space address. 42 * Returns 0 if the range is valid, nonzero otherwise. 43 */ 44 static inline int __range_not_ok(unsigned long addr, unsigned long size, 45 unsigned long limit) 46 { 47 unsigned long __newaddr = addr + size; 48 return (__newaddr < addr || __newaddr > limit || size > limit); 49 } 50 51 /** 52 * access_ok: - Checks if a user space pointer is valid 53 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that 54 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe 55 * to write to a block, it is always safe to read from it. 56 * @addr: User space pointer to start of block to check 57 * @size: Size of block to check 58 * 59 * Context: User context only. This function may sleep. 60 * 61 * Checks if a pointer to a block of memory in user space is valid. 62 * 63 * Returns true (nonzero) if the memory block may be valid, false (zero) 64 * if it is definitely invalid. 65 * 66 * Note that, depending on architecture, this function probably just 67 * checks that the pointer is in the user space range - after calling 68 * this function, memory access functions may still return -EFAULT. 69 */ 70 #define access_ok(type, addr, size) \ 71 ( __chk_user_ptr(addr), \ 72 !__range_not_ok((unsigned long) (__force void *) (addr), \ 73 size, user_addr_max()) \ 74 ) 75 76 #define put_user __put_user 77 #define get_user __get_user 78 79 #if !defined(CONFIG_64BIT) 80 #define LDD_KERNEL(ptr) __get_kernel_bad(); 81 #define LDD_USER(ptr) __get_user_bad(); 82 #define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr) 83 #define STD_USER(x, ptr) __put_user_asm64(x,ptr) 84 #define ASM_WORD_INSN ".word\t" 85 #else 86 #define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr) 87 #define LDD_USER(ptr) __get_user_asm("ldd",ptr) 88 #define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr) 89 #define STD_USER(x, ptr) __put_user_asm("std",x,ptr) 90 #define ASM_WORD_INSN ".dword\t" 91 #endif 92 93 /* 94 * The exception table contains two values: the first is an address 95 * for an instruction that is allowed to fault, and the second is 96 * the address to the fixup routine. Even on a 64bit kernel we could 97 * use a 32bit (unsigned int) address here. 98 */ 99 100 struct exception_table_entry { 101 unsigned long insn; /* address of insn that is allowed to fault. */ 102 unsigned long fixup; /* fixup routine */ 103 }; 104 105 #define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ 106 ".section __ex_table,\"aw\"\n" \ 107 ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \ 108 ".previous\n" 109 110 /* 111 * The page fault handler stores, in a per-cpu area, the following information 112 * if a fixup routine is available. 113 */ 114 struct exception_data { 115 unsigned long fault_ip; 116 unsigned long fault_space; 117 unsigned long fault_addr; 118 }; 119 120 #define __get_user(x,ptr) \ 121 ({ \ 122 register long __gu_err __asm__ ("r8") = 0; \ 123 register long __gu_val __asm__ ("r9") = 0; \ 124 \ 125 if (segment_eq(get_fs(),KERNEL_DS)) { \ 126 switch (sizeof(*(ptr))) { \ 127 case 1: __get_kernel_asm("ldb",ptr); break; \ 128 case 2: __get_kernel_asm("ldh",ptr); break; \ 129 case 4: __get_kernel_asm("ldw",ptr); break; \ 130 case 8: LDD_KERNEL(ptr); break; \ 131 default: __get_kernel_bad(); break; \ 132 } \ 133 } \ 134 else { \ 135 switch (sizeof(*(ptr))) { \ 136 case 1: __get_user_asm("ldb",ptr); break; \ 137 case 2: __get_user_asm("ldh",ptr); break; \ 138 case 4: __get_user_asm("ldw",ptr); break; \ 139 case 8: LDD_USER(ptr); break; \ 140 default: __get_user_bad(); break; \ 141 } \ 142 } \ 143 \ 144 (x) = (__typeof__(*(ptr))) __gu_val; \ 145 __gu_err; \ 146 }) 147 148 #define __get_kernel_asm(ldx,ptr) \ 149 __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \ 150 ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ 151 : "=r"(__gu_val), "=r"(__gu_err) \ 152 : "r"(ptr), "1"(__gu_err) \ 153 : "r1"); 154 155 #define __get_user_asm(ldx,ptr) \ 156 __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \ 157 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\ 158 : "=r"(__gu_val), "=r"(__gu_err) \ 159 : "r"(ptr), "1"(__gu_err) \ 160 : "r1"); 161 162 #define __put_user(x,ptr) \ 163 ({ \ 164 register long __pu_err __asm__ ("r8") = 0; \ 165 __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \ 166 \ 167 if (segment_eq(get_fs(),KERNEL_DS)) { \ 168 switch (sizeof(*(ptr))) { \ 169 case 1: __put_kernel_asm("stb",__x,ptr); break; \ 170 case 2: __put_kernel_asm("sth",__x,ptr); break; \ 171 case 4: __put_kernel_asm("stw",__x,ptr); break; \ 172 case 8: STD_KERNEL(__x,ptr); break; \ 173 default: __put_kernel_bad(); break; \ 174 } \ 175 } \ 176 else { \ 177 switch (sizeof(*(ptr))) { \ 178 case 1: __put_user_asm("stb",__x,ptr); break; \ 179 case 2: __put_user_asm("sth",__x,ptr); break; \ 180 case 4: __put_user_asm("stw",__x,ptr); break; \ 181 case 8: STD_USER(__x,ptr); break; \ 182 default: __put_user_bad(); break; \ 183 } \ 184 } \ 185 \ 186 __pu_err; \ 187 }) 188 189 /* 190 * The "__put_user/kernel_asm()" macros tell gcc they read from memory 191 * instead of writing. This is because they do not write to any memory 192 * gcc knows about, so there are no aliasing issues. These macros must 193 * also be aware that "fixup_put_user_skip_[12]" are executed in the 194 * context of the fault, and any registers used there must be listed 195 * as clobbers. In this case only "r1" is used by the current routines. 196 * r8/r9 are already listed as err/val. 197 */ 198 199 #define __put_kernel_asm(stx,x,ptr) \ 200 __asm__ __volatile__ ( \ 201 "\n1:\t" stx "\t%2,0(%1)\n\t" \ 202 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\ 203 : "=r"(__pu_err) \ 204 : "r"(ptr), "r"(x), "0"(__pu_err) \ 205 : "r1") 206 207 #define __put_user_asm(stx,x,ptr) \ 208 __asm__ __volatile__ ( \ 209 "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \ 210 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\ 211 : "=r"(__pu_err) \ 212 : "r"(ptr), "r"(x), "0"(__pu_err) \ 213 : "r1") 214 215 216 #if !defined(CONFIG_64BIT) 217 218 #define __put_kernel_asm64(__val,ptr) do { \ 219 __asm__ __volatile__ ( \ 220 "\n1:\tstw %2,0(%1)" \ 221 "\n2:\tstw %R2,4(%1)\n\t" \ 222 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ 223 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ 224 : "=r"(__pu_err) \ 225 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 226 : "r1"); \ 227 } while (0) 228 229 #define __put_user_asm64(__val,ptr) do { \ 230 __asm__ __volatile__ ( \ 231 "\n1:\tstw %2,0(%%sr3,%1)" \ 232 "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \ 233 ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ 234 ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ 235 : "=r"(__pu_err) \ 236 : "r"(ptr), "r"(__val), "0"(__pu_err) \ 237 : "r1"); \ 238 } while (0) 239 240 #endif /* !defined(CONFIG_64BIT) */ 241 242 243 /* 244 * Complex access routines -- external declarations 245 */ 246 247 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long); 248 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long); 249 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long); 250 extern long strncpy_from_user(char *, const char __user *, long); 251 extern unsigned lclear_user(void __user *,unsigned long); 252 extern long lstrnlen_user(const char __user *,long); 253 /* 254 * Complex access routines -- macros 255 */ 256 #ifdef CONFIG_COMPAT 257 #define user_addr_max() (TASK_SIZE) 258 #else 259 #define user_addr_max() (DEFAULT_TASK_SIZE) 260 #endif 261 262 #define strnlen_user lstrnlen_user 263 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL) 264 #define clear_user lclear_user 265 #define __clear_user lclear_user 266 267 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len); 268 #define __copy_to_user copy_to_user 269 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len); 270 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len); 271 #define __copy_in_user copy_in_user 272 #define __copy_to_user_inatomic __copy_to_user 273 #define __copy_from_user_inatomic __copy_from_user 274 275 extern void copy_from_user_overflow(void) 276 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 277 __compiletime_error("copy_from_user() buffer size is not provably correct") 278 #else 279 __compiletime_warning("copy_from_user() buffer size is not provably correct") 280 #endif 281 ; 282 283 static inline unsigned long __must_check copy_from_user(void *to, 284 const void __user *from, 285 unsigned long n) 286 { 287 int sz = __compiletime_object_size(to); 288 int ret = -EFAULT; 289 290 if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n)) 291 ret = __copy_from_user(to, from, n); 292 else 293 copy_from_user_overflow(); 294 295 return ret; 296 } 297 298 struct pt_regs; 299 int fixup_exception(struct pt_regs *regs); 300 301 #endif /* __PARISC_UACCESS_H */ 302