2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
15 #ifndef _ASM_TILE_UACCESS_H
16 #define _ASM_TILE_UACCESS_H
19 * User space memory access functions
22 #include <asm-generic/uaccess-unaligned.h>
23 #include <asm/processor.h>
27 * The fs value determines whether argument validity checking should be
28 * performed or not. If get_fs() == USER_DS, checking is performed, with
29 * get_fs() == KERNEL_DS, checking is bypassed.
31 * For historical reasons, these macros are grossly misnamed.
33 #define MAKE_MM_SEG(a) ((mm_segment_t) { (a) })
35 #define KERNEL_DS MAKE_MM_SEG(-1UL)
36 #define USER_DS MAKE_MM_SEG(PAGE_OFFSET)
38 #define get_ds() (KERNEL_DS)
39 #define get_fs() (current_thread_info()->addr_limit)
40 #define set_fs(x) (current_thread_info()->addr_limit = (x))
42 #define segment_eq(a, b) ((a).seg == (b).seg)
46 * We could allow mapping all 16 MB at 0xfc000000, but we set up a
47 * special hack in arch_setup_additional_pages() to auto-create a mapping
48 * for the first 16 KB, and it would seem strange to have different
49 * user-accessible semantics for memory at 0xfc000000 and above 0xfc004000.
51 static inline int is_arch_mappable_range(unsigned long addr,
54 return (addr >= MEM_USER_INTRPT &&
55 addr < (MEM_USER_INTRPT + INTRPT_SIZE) &&
56 size <= (MEM_USER_INTRPT + INTRPT_SIZE) - addr);
58 #define is_arch_mappable_range is_arch_mappable_range
60 #define is_arch_mappable_range(addr, size) 0
64 * Note that using this definition ignores is_arch_mappable_range(),
65 * so on tilepro code that uses user_addr_max() is constrained not
66 * to reference the tilepro user-interrupt region.
68 #define user_addr_max() (current_thread_info()->addr_limit.seg)
71 * Test whether a block of memory is a valid user space address.
72 * Returns 0 if the range is valid, nonzero otherwise.
74 int __range_ok(unsigned long addr, unsigned long size);
77 * access_ok: - Checks if a user space pointer is valid
78 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
79 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
80 * to write to a block, it is always safe to read from it.
81 * @addr: User space pointer to start of block to check
82 * @size: Size of block to check
84 * Context: User context only. This function may sleep if pagefaults are
87 * Checks if a pointer to a block of memory in user space is valid.
89 * Returns true (nonzero) if the memory block may be valid, false (zero)
90 * if it is definitely invalid.
92 * Note that, depending on architecture, this function probably just
93 * checks that the pointer is in the user space range - after calling
94 * this function, memory access functions may still return -EFAULT.
96 #define access_ok(type, addr, size) ({ \
97 __chk_user_ptr(addr); \
98 likely(__range_ok((unsigned long)(addr), (size)) == 0); \
101 #include <asm/extable.h>
104 * This is a type: either unsigned long, if the argument fits into
105 * that type, or otherwise unsigned long long.
107 #define __inttype(x) \
108 __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
111 * Support macros for __get_user().
112 * Note that __get_user() and __put_user() assume proper alignment.
116 #define _ASM_PTR ".quad"
117 #define _ASM_ALIGN ".align 8"
119 #define _ASM_PTR ".long"
120 #define _ASM_ALIGN ".align 4"
123 #define __get_user_asm(OP, x, ptr, ret) \
124 asm volatile("1: {" #OP " %1, %2; movei %0, 0 }\n" \
125 ".pushsection .fixup,\"ax\"\n" \
126 "0: { movei %1, 0; movei %0, %3 }\n" \
128 ".section __ex_table,\"a\"\n" \
130 _ASM_PTR " 1b, 0b\n" \
133 : "=r" (ret), "=r" (x) \
134 : "r" (ptr), "i" (-EFAULT))
137 #define __get_user_1(x, ptr, ret) __get_user_asm(ld1u, x, ptr, ret)
138 #define __get_user_2(x, ptr, ret) __get_user_asm(ld2u, x, ptr, ret)
139 #define __get_user_4(x, ptr, ret) __get_user_asm(ld4s, x, ptr, ret)
140 #define __get_user_8(x, ptr, ret) __get_user_asm(ld, x, ptr, ret)
142 #define __get_user_1(x, ptr, ret) __get_user_asm(lb_u, x, ptr, ret)
143 #define __get_user_2(x, ptr, ret) __get_user_asm(lh_u, x, ptr, ret)
144 #define __get_user_4(x, ptr, ret) __get_user_asm(lw, x, ptr, ret)
145 #ifdef __LITTLE_ENDIAN
146 #define __lo32(a, b) a
147 #define __hi32(a, b) b
149 #define __lo32(a, b) b
150 #define __hi32(a, b) a
152 #define __get_user_8(x, ptr, ret) \
154 unsigned int __a, __b; \
155 asm volatile("1: { lw %1, %3; addi %2, %3, 4 }\n" \
156 "2: { lw %2, %2; movei %0, 0 }\n" \
157 ".pushsection .fixup,\"ax\"\n" \
158 "0: { movei %1, 0; movei %2, 0 }\n" \
159 "{ movei %0, %4; j 9f }\n" \
160 ".section __ex_table,\"a\"\n" \
166 : "=r" (ret), "=r" (__a), "=&r" (__b) \
167 : "r" (ptr), "i" (-EFAULT)); \
168 (x) = (__force __typeof(x))(__inttype(x)) \
169 (((u64)__hi32(__a, __b) << 32) | \
174 extern int __get_user_bad(void)
175 __attribute__((warning("sizeof __get_user argument not 1, 2, 4 or 8")));
178 * __get_user: - Get a simple variable from user space, with less checking.
179 * @x: Variable to store result.
180 * @ptr: Source address, in user space.
182 * Context: User context only. This function may sleep if pagefaults are
185 * This macro copies a single simple variable from user space to kernel
186 * space. It supports simple types like char and int, but not larger
187 * data types like structures or arrays.
189 * @ptr must have pointer-to-simple-variable type, and the result of
190 * dereferencing @ptr must be assignable to @x without a cast.
192 * Returns zero on success, or -EFAULT on error.
193 * On error, the variable @x is set to zero.
195 * Caller must check the pointer with access_ok() before calling this
198 #define __get_user(x, ptr) \
202 __chk_user_ptr(ptr); \
203 switch (sizeof(*(ptr))) { \
204 case 1: __get_user_1(_x, ptr, __ret); break; \
205 case 2: __get_user_2(_x, ptr, __ret); break; \
206 case 4: __get_user_4(_x, ptr, __ret); break; \
207 case 8: __get_user_8(_x, ptr, __ret); break; \
208 default: __ret = __get_user_bad(); break; \
210 (x) = (typeof(*(ptr))) _x; \
214 /* Support macros for __put_user(). */
216 #define __put_user_asm(OP, x, ptr, ret) \
217 asm volatile("1: {" #OP " %1, %2; movei %0, 0 }\n" \
218 ".pushsection .fixup,\"ax\"\n" \
219 "0: { movei %0, %3; j 9f }\n" \
220 ".section __ex_table,\"a\"\n" \
222 _ASM_PTR " 1b, 0b\n" \
226 : "r" (ptr), "r" (x), "i" (-EFAULT))
229 #define __put_user_1(x, ptr, ret) __put_user_asm(st1, x, ptr, ret)
230 #define __put_user_2(x, ptr, ret) __put_user_asm(st2, x, ptr, ret)
231 #define __put_user_4(x, ptr, ret) __put_user_asm(st4, x, ptr, ret)
232 #define __put_user_8(x, ptr, ret) __put_user_asm(st, x, ptr, ret)
234 #define __put_user_1(x, ptr, ret) __put_user_asm(sb, x, ptr, ret)
235 #define __put_user_2(x, ptr, ret) __put_user_asm(sh, x, ptr, ret)
236 #define __put_user_4(x, ptr, ret) __put_user_asm(sw, x, ptr, ret)
237 #define __put_user_8(x, ptr, ret) \
239 u64 __x = (__force __inttype(x))(x); \
240 int __lo = (int) __x, __hi = (int) (__x >> 32); \
241 asm volatile("1: { sw %1, %2; addi %0, %1, 4 }\n" \
242 "2: { sw %0, %3; movei %0, 0 }\n" \
243 ".pushsection .fixup,\"ax\"\n" \
244 "0: { movei %0, %4; j 9f }\n" \
245 ".section __ex_table,\"a\"\n" \
252 : "r" (ptr), "r" (__lo32(__lo, __hi)), \
253 "r" (__hi32(__lo, __hi)), "i" (-EFAULT)); \
257 extern int __put_user_bad(void)
258 __attribute__((warning("sizeof __put_user argument not 1, 2, 4 or 8")));
261 * __put_user: - Write a simple value into user space, with less checking.
262 * @x: Value to copy to user space.
263 * @ptr: Destination address, in user space.
265 * Context: User context only. This function may sleep if pagefaults are
268 * This macro copies a single simple value from kernel space to user
269 * space. It supports simple types like char and int, but not larger
270 * data types like structures or arrays.
272 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
273 * to the result of dereferencing @ptr.
275 * Caller must check the pointer with access_ok() before calling this
278 * Returns zero on success, or -EFAULT on error.
280 #define __put_user(x, ptr) \
283 typeof(*(ptr)) _x = (x); \
284 __chk_user_ptr(ptr); \
285 switch (sizeof(*(ptr))) { \
286 case 1: __put_user_1(_x, ptr, __ret); break; \
287 case 2: __put_user_2(_x, ptr, __ret); break; \
288 case 4: __put_user_4(_x, ptr, __ret); break; \
289 case 8: __put_user_8(_x, ptr, __ret); break; \
290 default: __ret = __put_user_bad(); break; \
296 * The versions of get_user and put_user without initial underscores
297 * check the address of their arguments to make sure they are not
300 #define put_user(x, ptr) \
302 __typeof__(*(ptr)) __user *__Pu_addr = (ptr); \
303 access_ok(VERIFY_WRITE, (__Pu_addr), sizeof(*(__Pu_addr))) ? \
304 __put_user((x), (__Pu_addr)) : \
308 #define get_user(x, ptr) \
310 __typeof__(*(ptr)) const __user *__Gu_addr = (ptr); \
311 access_ok(VERIFY_READ, (__Gu_addr), sizeof(*(__Gu_addr))) ? \
312 __get_user((x), (__Gu_addr)) : \
313 ((x) = 0, -EFAULT); \
317 * __copy_to_user() - copy data into user space, with less checking.
318 * @to: Destination address, in user space.
319 * @from: Source address, in kernel space.
320 * @n: Number of bytes to copy.
322 * Context: User context only. This function may sleep if pagefaults are
325 * Copy data from kernel space to user space. Caller must check
326 * the specified block with access_ok() before calling this function.
328 * Returns number of bytes that could not be copied.
329 * On success, this will be zero.
331 * An alternate version - __copy_to_user_inatomic() - is designed
332 * to be called from atomic context, typically bracketed by calls
333 * to pagefault_disable() and pagefault_enable().
335 extern unsigned long __must_check __copy_to_user_inatomic(
336 void __user *to, const void *from, unsigned long n);
338 static inline unsigned long __must_check
339 __copy_to_user(void __user *to, const void *from, unsigned long n)
342 return __copy_to_user_inatomic(to, from, n);
345 static inline unsigned long __must_check
346 copy_to_user(void __user *to, const void *from, unsigned long n)
348 if (access_ok(VERIFY_WRITE, to, n))
349 n = __copy_to_user(to, from, n);
354 * __copy_from_user() - copy data from user space, with less checking.
355 * @to: Destination address, in kernel space.
356 * @from: Source address, in user space.
357 * @n: Number of bytes to copy.
359 * Context: User context only. This function may sleep if pagefaults are
362 * Copy data from user space to kernel space. Caller must check
363 * the specified block with access_ok() before calling this function.
365 * Returns number of bytes that could not be copied.
366 * On success, this will be zero.
368 * If some data could not be copied, this function will pad the copied
369 * data to the requested size using zero bytes.
371 * An alternate version - __copy_from_user_inatomic() - is designed
372 * to be called from atomic context, typically bracketed by calls
373 * to pagefault_disable() and pagefault_enable(). This version
374 * does *NOT* pad with zeros.
376 extern unsigned long __must_check __copy_from_user_inatomic(
377 void *to, const void __user *from, unsigned long n);
378 extern unsigned long __must_check __copy_from_user_zeroing(
379 void *to, const void __user *from, unsigned long n);
381 static inline unsigned long __must_check
382 __copy_from_user(void *to, const void __user *from, unsigned long n)
385 return __copy_from_user_zeroing(to, from, n);
388 static inline unsigned long __must_check
389 _copy_from_user(void *to, const void __user *from, unsigned long n)
391 if (access_ok(VERIFY_READ, from, n))
392 n = __copy_from_user(to, from, n);
398 extern void __compiletime_error("usercopy buffer size is too small")
399 __bad_copy_user(void);
401 static inline void copy_user_overflow(int size, unsigned long count)
403 WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
406 static inline unsigned long __must_check copy_from_user(void *to,
407 const void __user *from,
410 int sz = __compiletime_object_size(to);
412 if (likely(sz == -1 || sz >= n))
413 n = _copy_from_user(to, from, n);
414 else if (!__builtin_constant_p(n))
415 copy_user_overflow(sz, n);
424 * __copy_in_user() - copy data within user space, with less checking.
425 * @to: Destination address, in user space.
426 * @from: Source address, in user space.
427 * @n: Number of bytes to copy.
429 * Context: User context only. This function may sleep if pagefaults are
432 * Copy data from user space to user space. Caller must check
433 * the specified blocks with access_ok() before calling this function.
435 * Returns number of bytes that could not be copied.
436 * On success, this will be zero.
438 extern unsigned long __copy_in_user_inatomic(
439 void __user *to, const void __user *from, unsigned long n);
441 static inline unsigned long __must_check
442 __copy_in_user(void __user *to, const void __user *from, unsigned long n)
445 return __copy_in_user_inatomic(to, from, n);
448 static inline unsigned long __must_check
449 copy_in_user(void __user *to, const void __user *from, unsigned long n)
451 if (access_ok(VERIFY_WRITE, to, n) && access_ok(VERIFY_READ, from, n))
452 n = __copy_in_user(to, from, n);
458 extern long strnlen_user(const char __user *str, long n);
459 extern long strlen_user(const char __user *str);
460 extern long strncpy_from_user(char *dst, const char __user *src, long);
463 * clear_user: - Zero a block of memory in user space.
464 * @mem: Destination address, in user space.
465 * @len: Number of bytes to zero.
467 * Zero a block of memory in user space.
469 * Returns number of bytes that could not be cleared.
470 * On success, this will be zero.
472 extern unsigned long clear_user_asm(void __user *mem, unsigned long len);
473 static inline unsigned long __must_check __clear_user(
474 void __user *mem, unsigned long len)
477 return clear_user_asm(mem, len);
479 static inline unsigned long __must_check clear_user(
480 void __user *mem, unsigned long len)
482 if (access_ok(VERIFY_WRITE, mem, len))
483 return __clear_user(mem, len);
488 * flush_user: - Flush a block of memory in user space from cache.
489 * @mem: Destination address, in user space.
490 * @len: Number of bytes to flush.
492 * Returns number of bytes that could not be flushed.
493 * On success, this will be zero.
495 extern unsigned long flush_user_asm(void __user *mem, unsigned long len);
496 static inline unsigned long __must_check __flush_user(
497 void __user *mem, unsigned long len)
502 retval = flush_user_asm(mem, len);
507 static inline unsigned long __must_check flush_user(
508 void __user *mem, unsigned long len)
510 if (access_ok(VERIFY_WRITE, mem, len))
511 return __flush_user(mem, len);
516 * finv_user: - Flush-inval a block of memory in user space from cache.
517 * @mem: Destination address, in user space.
518 * @len: Number of bytes to invalidate.
520 * Returns number of bytes that could not be flush-invalidated.
521 * On success, this will be zero.
523 extern unsigned long finv_user_asm(void __user *mem, unsigned long len);
524 static inline unsigned long __must_check __finv_user(
525 void __user *mem, unsigned long len)
530 retval = finv_user_asm(mem, len);
534 static inline unsigned long __must_check finv_user(
535 void __user *mem, unsigned long len)
537 if (access_ok(VERIFY_WRITE, mem, len))
538 return __finv_user(mem, len);
542 #endif /* _ASM_TILE_UACCESS_H */