Linux-2.6.12-rc2
[linux-3.10.git] / include / asm-m32r / uaccess.h
1 #ifndef _ASM_M32R_UACCESS_H
2 #define _ASM_M32R_UACCESS_H
3
4 /*
5  *  linux/include/asm-m32r/uaccess.h
6  *
7  *  M32R version.
8  *    Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
9  */
10
11 #undef UACCESS_DEBUG
12
13 #ifdef UACCESS_DEBUG
14 #define UAPRINTK(args...) printk(args)
15 #else
16 #define UAPRINTK(args...)
17 #endif /* UACCESS_DEBUG */
18
19 /*
20  * User space memory access functions
21  */
22 #include <linux/config.h>
23 #include <linux/errno.h>
24 #include <linux/thread_info.h>
25 #include <asm/page.h>
26
27 #define VERIFY_READ 0
28 #define VERIFY_WRITE 1
29
30 /*
31  * The fs value determines whether argument validity checking should be
32  * performed or not.  If get_fs() == USER_DS, checking is performed, with
33  * get_fs() == KERNEL_DS, checking is bypassed.
34  *
35  * For historical reasons, these macros are grossly misnamed.
36  */
37
38 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
39
40 #ifdef CONFIG_MMU
41 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
42 #define USER_DS         MAKE_MM_SEG(PAGE_OFFSET)
43 #else
44 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
45 #define USER_DS         MAKE_MM_SEG(0xFFFFFFFF)
46 #endif /* CONFIG_MMU */
47
48 #define get_ds()        (KERNEL_DS)
49 #ifdef CONFIG_MMU
50 #define get_fs()        (current_thread_info()->addr_limit)
51 #define set_fs(x)       (current_thread_info()->addr_limit = (x))
52 #else
53 static inline mm_segment_t get_fs(void)
54 {
55   return USER_DS;
56 }
57
58 static inline void set_fs(mm_segment_t s)
59 {
60 }
61 #endif /* CONFIG_MMU */
62
63 #define segment_eq(a,b) ((a).seg == (b).seg)
64
65 #define __addr_ok(addr) \
66         ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
67
68 /*
69  * Test whether a block of memory is a valid user space address.
70  * Returns 0 if the range is valid, nonzero otherwise.
71  *
72  * This is equivalent to the following test:
73  * (u33)addr + (u33)size >= (u33)current->addr_limit.seg
74  *
75  * This needs 33-bit arithmetic. We have a carry...
76  */
77 #define __range_ok(addr,size) ({                                        \
78         unsigned long flag, sum;                                        \
79         __chk_user_ptr(addr);                                           \
80         asm (                                                           \
81                 "       cmpu    %1, %1    ; clear cbit\n"               \
82                 "       addx    %1, %3    ; set cbit if overflow\n"     \
83                 "       subx    %0, %0\n"                               \
84                 "       cmpu    %4, %1\n"                               \
85                 "       subx    %0, %5\n"                               \
86                 : "=&r"(flag), "=r"(sum)                                \
87                 : "1"(addr), "r"((int)(size)),                          \
88                   "r"(current_thread_info()->addr_limit.seg), "r"(0)    \
89                 : "cbit" );                                             \
90         flag; })
91
92 /**
93  * access_ok: - Checks if a user space pointer is valid
94  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
95  *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
96  *        to write to a block, it is always safe to read from it.
97  * @addr: User space pointer to start of block to check
98  * @size: Size of block to check
99  *
100  * Context: User context only.  This function may sleep.
101  *
102  * Checks if a pointer to a block of memory in user space is valid.
103  *
104  * Returns true (nonzero) if the memory block may be valid, false (zero)
105  * if it is definitely invalid.
106  *
107  * Note that, depending on architecture, this function probably just
108  * checks that the pointer is in the user space range - after calling
109  * this function, memory access functions may still return -EFAULT.
110  */
111 #ifdef CONFIG_MMU
112 #define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0))
113 #else
114 static inline int access_ok(int type, const void *addr, unsigned long size)
115 {
116   extern unsigned long memory_start, memory_end;
117   unsigned long val = (unsigned long)addr;
118
119   return ((val >= memory_start) && ((val + size) < memory_end));
120 }
121 #endif /* CONFIG_MMU */
122
123 /**
124  * verify_area: - Obsolete/deprecated and will go away soon,
125  * use access_ok() instead.
126  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE
127  * @addr: User space pointer to start of block to check
128  * @size: Size of block to check
129  *
130  * Context: User context only.  This function may sleep.
131  *
132  * This function has been replaced by access_ok().
133  *
134  * Checks if a pointer to a block of memory in user space is valid.
135  *
136  * Returns zero if the memory block may be valid, -EFAULT
137  * if it is definitely invalid.
138  *
139  * See access_ok() for more details.
140  */
141 static inline int __deprecated verify_area(int type, const void __user *addr,
142                               unsigned long size)
143 {
144         return access_ok(type, addr, size) ? 0 : -EFAULT;
145 }
146
147
148 /*
149  * The exception table consists of pairs of addresses: the first is the
150  * address of an instruction that is allowed to fault, and the second is
151  * the address at which the program should continue.  No registers are
152  * modified, so it is entirely up to the continuation code to figure out
153  * what to do.
154  *
155  * All the routines below use bits of fixup code that are out of line
156  * with the main instruction path.  This means when everything is well,
157  * we don't even have to jump over them.  Further, they do not intrude
158  * on our cache or tlb entries.
159  */
160
161 struct exception_table_entry
162 {
163         unsigned long insn, fixup;
164 };
165
166 extern int fixup_exception(struct pt_regs *regs);
167
168 /*
169  * These are the main single-value transfer routines.  They automatically
170  * use the right size if we just have the right pointer type.
171  *
172  * This gets kind of ugly. We want to return _two_ values in "get_user()"
173  * and yet we don't want to do any pointers, because that is too much
174  * of a performance impact. Thus we have a few rather ugly macros here,
175  * and hide all the uglyness from the user.
176  *
177  * The "__xxx" versions of the user access functions are versions that
178  * do not verify the address space, that must have been done previously
179  * with a separate "access_ok()" call (this is used when we do multiple
180  * accesses to the same area of user memory).
181  */
182
183 extern void __get_user_1(void);
184 extern void __get_user_2(void);
185 extern void __get_user_4(void);
186
187 #ifndef MODULE
188 #define __get_user_x(size,ret,x,ptr)                                    \
189         __asm__ __volatile__(                                           \
190                 "       mv      r0, %0\n"                               \
191                 "       mv      r1, %1\n"                               \
192                 "       bl __get_user_" #size "\n"                      \
193                 "       mv      %0, r0\n"                               \
194                 "       mv      %1, r1\n"                               \
195                 : "=r"(ret), "=r"(x)                                    \
196                 : "0"(ptr)                                              \
197                 : "r0", "r1", "r14" )
198 #else /* MODULE */
199 /*
200  * Use "jl" instead of "bl" for MODULE
201  */
202 #define __get_user_x(size,ret,x,ptr)                                    \
203         __asm__ __volatile__(                                           \
204                 "       mv      r0, %0\n"                               \
205                 "       mv      r1, %1\n"                               \
206                 "       seth    lr, #high(__get_user_" #size ")\n"      \
207                 "       or3     lr, lr, #low(__get_user_" #size ")\n"   \
208                 "       jl      lr\n"                                   \
209                 "       mv      %0, r0\n"                               \
210                 "       mv      %1, r1\n"                               \
211                 : "=r"(ret), "=r"(x)                                    \
212                 : "0"(ptr)                                              \
213                 : "r0", "r1", "r14" )
214 #endif
215
216 /* Careful: we have to cast the result to the type of the pointer for sign
217    reasons */
218 /**
219  * get_user: - Get a simple variable from user space.
220  * @x:   Variable to store result.
221  * @ptr: Source address, in user space.
222  *
223  * Context: User context only.  This function may sleep.
224  *
225  * This macro copies a single simple variable from user space to kernel
226  * space.  It supports simple types like char and int, but not larger
227  * data types like structures or arrays.
228  *
229  * @ptr must have pointer-to-simple-variable type, and the result of
230  * dereferencing @ptr must be assignable to @x without a cast.
231  *
232  * Returns zero on success, or -EFAULT on error.
233  * On error, the variable @x is set to zero.
234  */
235 #define get_user(x,ptr)                                                 \
236 ({      int __ret_gu,__val_gu;                                          \
237         __chk_user_ptr(ptr);                                            \
238         switch(sizeof (*(ptr))) {                                       \
239         case 1:  __get_user_x(1,__ret_gu,__val_gu,ptr); break;          \
240         case 2:  __get_user_x(2,__ret_gu,__val_gu,ptr); break;          \
241         case 4:  __get_user_x(4,__ret_gu,__val_gu,ptr); break;          \
242         default: __get_user_x(X,__ret_gu,__val_gu,ptr); break;          \
243         }                                                               \
244         (x) = (__typeof__(*(ptr)))__val_gu;                             \
245         __ret_gu;                                                       \
246 })
247
248 extern void __put_user_bad(void);
249
250 /**
251  * put_user: - Write a simple value into user space.
252  * @x:   Value to copy to user space.
253  * @ptr: Destination address, in user space.
254  *
255  * Context: User context only.  This function may sleep.
256  *
257  * This macro copies a single simple value from kernel space to user
258  * space.  It supports simple types like char and int, but not larger
259  * data types like structures or arrays.
260  *
261  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
262  * to the result of dereferencing @ptr.
263  *
264  * Returns zero on success, or -EFAULT on error.
265  */
266 #define put_user(x,ptr)                                                 \
267   __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
268
269
270 /**
271  * __get_user: - Get a simple variable from user space, with less checking.
272  * @x:   Variable to store result.
273  * @ptr: Source address, in user space.
274  *
275  * Context: User context only.  This function may sleep.
276  *
277  * This macro copies a single simple variable from user space to kernel
278  * space.  It supports simple types like char and int, but not larger
279  * data types like structures or arrays.
280  *
281  * @ptr must have pointer-to-simple-variable type, and the result of
282  * dereferencing @ptr must be assignable to @x without a cast.
283  *
284  * Caller must check the pointer with access_ok() before calling this
285  * function.
286  *
287  * Returns zero on success, or -EFAULT on error.
288  * On error, the variable @x is set to zero.
289  */
290 #define __get_user(x,ptr) \
291   __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
292
293
294 /**
295  * __put_user: - Write a simple value into user space, with less checking.
296  * @x:   Value to copy to user space.
297  * @ptr: Destination address, in user space.
298  *
299  * Context: User context only.  This function may sleep.
300  *
301  * This macro copies a single simple value from kernel space to user
302  * space.  It supports simple types like char and int, but not larger
303  * data types like structures or arrays.
304  *
305  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
306  * to the result of dereferencing @ptr.
307  *
308  * Caller must check the pointer with access_ok() before calling this
309  * function.
310  *
311  * Returns zero on success, or -EFAULT on error.
312  */
313 #define __put_user(x,ptr) \
314   __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
315
316 #define __put_user_nocheck(x,ptr,size)                                  \
317 ({                                                                      \
318         long __pu_err;                                                  \
319         __put_user_size((x),(ptr),(size),__pu_err);                     \
320         __pu_err;                                                       \
321 })
322
323
324 #define __put_user_check(x,ptr,size)                                    \
325 ({                                                                      \
326         long __pu_err = -EFAULT;                                        \
327         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
328         might_sleep();                                                  \
329         if (access_ok(VERIFY_WRITE,__pu_addr,size))                     \
330                 __put_user_size((x),__pu_addr,(size),__pu_err);         \
331         __pu_err;                                                       \
332 })
333
334 #if defined(__LITTLE_ENDIAN__)
335 #define __put_user_u64(x, addr, err)                                    \
336         __asm__ __volatile__(                                           \
337                 "       .fillinsn\n"                                    \
338                 "1:     st %L1,@%2\n"                                    \
339                 "       .fillinsn\n"                                    \
340                 "2:     st %H1,@(4,%2)\n"                                \
341                 "       .fillinsn\n"                                    \
342                 "3:\n"                                                  \
343                 ".section .fixup,\"ax\"\n"                              \
344                 "       .balign 4\n"                                    \
345                 "4:     ldi %0,%3\n"                                    \
346                 "       seth r14,#high(3b)\n"                           \
347                 "       or3 r14,r14,#low(3b)\n"                         \
348                 "       jmp r14\n"                                      \
349                 ".previous\n"                                           \
350                 ".section __ex_table,\"a\"\n"                           \
351                 "       .balign 4\n"                                    \
352                 "       .long 1b,4b\n"                                  \
353                 "       .long 2b,4b\n"                                  \
354                 ".previous"                                             \
355                 : "=r"(err)                                             \
356                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
357                 : "r14", "memory")
358
359 #elif defined(__BIG_ENDIAN__)
360 #define __put_user_u64(x, addr, err)                                    \
361         __asm__ __volatile__(                                           \
362                 "       .fillinsn\n"                                    \
363                 "1:     st %H1,@%2\n"                                   \
364                 "       .fillinsn\n"                                    \
365                 "2:     st %L1,@(4,%2)\n"                               \
366                 "       .fillinsn\n"                                    \
367                 "3:\n"                                                  \
368                 ".section .fixup,\"ax\"\n"                              \
369                 "       .balign 4\n"                                    \
370                 "4:     ldi %0,%3\n"                                    \
371                 "       seth r14,#high(3b)\n"                           \
372                 "       or3 r14,r14,#low(3b)\n"                         \
373                 "       jmp r14\n"                                      \
374                 ".previous\n"                                           \
375                 ".section __ex_table,\"a\"\n"                           \
376                 "       .balign 4\n"                                    \
377                 "       .long 1b,4b\n"                                  \
378                 "       .long 2b,4b\n"                                  \
379                 ".previous"                                             \
380                 : "=r"(err)                                             \
381                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
382                 : "r14", "memory")
383 #else
384 #error no endian defined
385 #endif
386
387 #define __put_user_size(x,ptr,size,retval)                              \
388 do {                                                                    \
389         retval = 0;                                                     \
390         __chk_user_ptr(ptr);                                            \
391         switch (size) {                                                 \
392           case 1: __put_user_asm(x,ptr,retval,"b"); break;              \
393           case 2: __put_user_asm(x,ptr,retval,"h"); break;              \
394           case 4: __put_user_asm(x,ptr,retval,""); break;               \
395           case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\
396           default: __put_user_bad();                                    \
397         }                                                               \
398 } while (0)
399
400 struct __large_struct { unsigned long buf[100]; };
401 #define __m(x) (*(struct __large_struct *)(x))
402
403 /*
404  * Tell gcc we read from memory instead of writing: this is because
405  * we do not write to any memory gcc knows about, so there are no
406  * aliasing issues.
407  */
408 #define __put_user_asm(x, addr, err, itype)                             \
409         __asm__ __volatile__(                                           \
410                 "       .fillinsn\n"                                    \
411                 "1:     st"itype" %1,@%2\n"                             \
412                 "       .fillinsn\n"                                    \
413                 "2:\n"                                                  \
414                 ".section .fixup,\"ax\"\n"                              \
415                 "       .balign 4\n"                                    \
416                 "3:     ldi %0,%3\n"                                    \
417                 "       seth r14,#high(2b)\n"                           \
418                 "       or3 r14,r14,#low(2b)\n"                         \
419                 "       jmp r14\n"                                      \
420                 ".previous\n"                                           \
421                 ".section __ex_table,\"a\"\n"                           \
422                 "       .balign 4\n"                                    \
423                 "       .long 1b,3b\n"                                  \
424                 ".previous"                                             \
425                 : "=r"(err)                                             \
426                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
427                 : "r14", "memory")
428
429 #define __get_user_nocheck(x,ptr,size)                                  \
430 ({                                                                      \
431         long __gu_err, __gu_val;                                        \
432         __get_user_size(__gu_val,(ptr),(size),__gu_err);                \
433         (x) = (__typeof__(*(ptr)))__gu_val;                             \
434         __gu_err;                                                       \
435 })
436
437 extern long __get_user_bad(void);
438
439 #define __get_user_size(x,ptr,size,retval)                              \
440 do {                                                                    \
441         retval = 0;                                                     \
442         __chk_user_ptr(ptr);                                            \
443         switch (size) {                                                 \
444           case 1: __get_user_asm(x,ptr,retval,"ub"); break;             \
445           case 2: __get_user_asm(x,ptr,retval,"uh"); break;             \
446           case 4: __get_user_asm(x,ptr,retval,""); break;               \
447           default: (x) = __get_user_bad();                              \
448         }                                                               \
449 } while (0)
450
451 #define __get_user_asm(x, addr, err, itype)                             \
452         __asm__ __volatile__(                                           \
453                 "       .fillinsn\n"                                    \
454                 "1:     ld"itype" %1,@%2\n"                             \
455                 "       .fillinsn\n"                                    \
456                 "2:\n"                                                  \
457                 ".section .fixup,\"ax\"\n"                              \
458                 "       .balign 4\n"                                    \
459                 "3:     ldi %0,%3\n"                                    \
460                 "       seth r14,#high(2b)\n"                           \
461                 "       or3 r14,r14,#low(2b)\n"                         \
462                 "       jmp r14\n"                                      \
463                 ".previous\n"                                           \
464                 ".section __ex_table,\"a\"\n"                           \
465                 "       .balign 4\n"                                    \
466                 "       .long 1b,3b\n"                                  \
467                 ".previous"                                             \
468                 : "=r"(err), "=&r"(x)                                   \
469                 : "r"(addr), "i"(-EFAULT), "0"(err)                     \
470                 : "r14", "memory")
471
472 /*
473  * Here we special-case 1, 2 and 4-byte copy_*_user invocations.  On a fault
474  * we return the initial request size (1, 2 or 4), as copy_*_user should do.
475  * If a store crosses a page boundary and gets a fault, the m32r will not write
476  * anything, so this is accurate.
477  */
478
479
480 /*
481  * Copy To/From Userspace
482  */
483
484 /* Generic arbitrary sized copy.  */
485 /* Return the number of bytes NOT copied.  */
486 #define __copy_user(to,from,size)                                       \
487 do {                                                                    \
488         unsigned long __dst, __src, __c;                                \
489         __asm__ __volatile__ (                                          \
490                 "       mv      r14, %0\n"                              \
491                 "       or      r14, %1\n"                              \
492                 "       beq     %0, %1, 9f\n"                           \
493                 "       beqz    %2, 9f\n"                               \
494                 "       and3    r14, r14, #3\n"                         \
495                 "       bnez    r14, 2f\n"                              \
496                 "       and3    %2, %2, #3\n"                           \
497                 "       beqz    %3, 2f\n"                               \
498                 "       addi    %0, #-4         ; word_copy \n"         \
499                 "       .fillinsn\n"                                    \
500                 "0:     ld      r14, @%1+\n"                            \
501                 "       addi    %3, #-1\n"                              \
502                 "       .fillinsn\n"                                    \
503                 "1:     st      r14, @+%0\n"                            \
504                 "       bnez    %3, 0b\n"                               \
505                 "       beqz    %2, 9f\n"                               \
506                 "       addi    %0, #4\n"                               \
507                 "       .fillinsn\n"                                    \
508                 "2:     ldb     r14, @%1        ; byte_copy \n"         \
509                 "       .fillinsn\n"                                    \
510                 "3:     stb     r14, @%0\n"                             \
511                 "       addi    %1, #1\n"                               \
512                 "       addi    %2, #-1\n"                              \
513                 "       addi    %0, #1\n"                               \
514                 "       bnez    %2, 2b\n"                               \
515                 "       .fillinsn\n"                                    \
516                 "9:\n"                                                  \
517                 ".section .fixup,\"ax\"\n"                              \
518                 "       .balign 4\n"                                    \
519                 "5:     addi    %3, #1\n"                               \
520                 "       addi    %1, #-4\n"                              \
521                 "       .fillinsn\n"                                    \
522                 "6:     slli    %3, #2\n"                               \
523                 "       add     %2, %3\n"                               \
524                 "       addi    %0, #4\n"                               \
525                 "       .fillinsn\n"                                    \
526                 "7:     seth    r14, #high(9b)\n"                       \
527                 "       or3     r14, r14, #low(9b)\n"                   \
528                 "       jmp     r14\n"                                  \
529                 ".previous\n"                                           \
530                 ".section __ex_table,\"a\"\n"                           \
531                 "       .balign 4\n"                                    \
532                 "       .long 0b,6b\n"                                  \
533                 "       .long 1b,5b\n"                                  \
534                 "       .long 2b,9b\n"                                  \
535                 "       .long 3b,9b\n"                                  \
536                 ".previous\n"                                           \
537                 : "=&r"(__dst), "=&r"(__src), "=&r"(size), "=&r"(__c)   \
538                 : "0"(to), "1"(from), "2"(size), "3"(size / 4)          \
539                 : "r14", "memory");                                     \
540 } while (0)
541
542 #define __copy_user_zeroing(to,from,size)                               \
543 do {                                                                    \
544         unsigned long __dst, __src, __c;                                \
545         __asm__ __volatile__ (                                          \
546                 "       mv      r14, %0\n"                              \
547                 "       or      r14, %1\n"                              \
548                 "       beq     %0, %1, 9f\n"                           \
549                 "       beqz    %2, 9f\n"                               \
550                 "       and3    r14, r14, #3\n"                         \
551                 "       bnez    r14, 2f\n"                              \
552                 "       and3    %2, %2, #3\n"                           \
553                 "       beqz    %3, 2f\n"                               \
554                 "       addi    %0, #-4         ; word_copy \n"         \
555                 "       .fillinsn\n"                                    \
556                 "0:     ld      r14, @%1+\n"                            \
557                 "       addi    %3, #-1\n"                              \
558                 "       .fillinsn\n"                                    \
559                 "1:     st      r14, @+%0\n"                            \
560                 "       bnez    %3, 0b\n"                               \
561                 "       beqz    %2, 9f\n"                               \
562                 "       addi    %0, #4\n"                               \
563                 "       .fillinsn\n"                                    \
564                 "2:     ldb     r14, @%1        ; byte_copy \n"         \
565                 "       .fillinsn\n"                                    \
566                 "3:     stb     r14, @%0\n"                             \
567                 "       addi    %1, #1\n"                               \
568                 "       addi    %2, #-1\n"                              \
569                 "       addi    %0, #1\n"                               \
570                 "       bnez    %2, 2b\n"                               \
571                 "       .fillinsn\n"                                    \
572                 "9:\n"                                                  \
573                 ".section .fixup,\"ax\"\n"                              \
574                 "       .balign 4\n"                                    \
575                 "5:     addi    %3, #1\n"                               \
576                 "       addi    %1, #-4\n"                              \
577                 "       .fillinsn\n"                                    \
578                 "6:     slli    %3, #2\n"                               \
579                 "       add     %2, %3\n"                               \
580                 "       addi    %0, #4\n"                               \
581                 "       .fillinsn\n"                                    \
582                 "7:     ldi     r14, #0         ; store zero \n"        \
583                 "       .fillinsn\n"                                    \
584                 "8:     addi    %2, #-1\n"                              \
585                 "       stb     r14, @%0        ; ACE? \n"              \
586                 "       addi    %0, #1\n"                               \
587                 "       bnez    %2, 8b\n"                               \
588                 "       seth    r14, #high(9b)\n"                       \
589                 "       or3     r14, r14, #low(9b)\n"                   \
590                 "       jmp     r14\n"                                  \
591                 ".previous\n"                                           \
592                 ".section __ex_table,\"a\"\n"                           \
593                 "       .balign 4\n"                                    \
594                 "       .long 0b,6b\n"                                  \
595                 "       .long 1b,5b\n"                                  \
596                 "       .long 2b,7b\n"                                  \
597                 "       .long 3b,7b\n"                                  \
598                 ".previous\n"                                           \
599                 : "=&r"(__dst), "=&r"(__src), "=&r"(size), "=&r"(__c)   \
600                 : "0"(to), "1"(from), "2"(size), "3"(size / 4)          \
601                 : "r14", "memory");                                     \
602 } while (0)
603
604
605 /* We let the __ versions of copy_from/to_user inline, because they're often
606  * used in fast paths and have only a small space overhead.
607  */
608 static inline unsigned long __generic_copy_from_user_nocheck(void *to,
609         const void __user *from, unsigned long n)
610 {
611         __copy_user_zeroing(to,from,n);
612         return n;
613 }
614
615 static inline unsigned long __generic_copy_to_user_nocheck(void __user *to,
616         const void *from, unsigned long n)
617 {
618         __copy_user(to,from,n);
619         return n;
620 }
621
622 unsigned long __generic_copy_to_user(void *, const void *, unsigned long);
623 unsigned long __generic_copy_from_user(void *, const void *, unsigned long);
624
625 /**
626  * __copy_to_user: - Copy a block of data into user space, with less checking.
627  * @to:   Destination address, in user space.
628  * @from: Source address, in kernel space.
629  * @n:    Number of bytes to copy.
630  *
631  * Context: User context only.  This function may sleep.
632  *
633  * Copy data from kernel space to user space.  Caller must check
634  * the specified block with access_ok() before calling this function.
635  *
636  * Returns number of bytes that could not be copied.
637  * On success, this will be zero.
638  */
639 #define __copy_to_user(to,from,n)                       \
640         __generic_copy_to_user_nocheck((to),(from),(n))
641
642 #define __copy_to_user_inatomic __copy_to_user
643 #define __copy_from_user_inatomic __copy_from_user
644
645 /**
646  * copy_to_user: - Copy a block of data into user space.
647  * @to:   Destination address, in user space.
648  * @from: Source address, in kernel space.
649  * @n:    Number of bytes to copy.
650  *
651  * Context: User context only.  This function may sleep.
652  *
653  * Copy data from kernel space to user space.
654  *
655  * Returns number of bytes that could not be copied.
656  * On success, this will be zero.
657  */
658 #define copy_to_user(to,from,n)                         \
659 ({                                                      \
660         might_sleep();                                  \
661         __generic_copy_to_user((to),(from),(n));        \
662 })
663
664 /**
665  * __copy_from_user: - Copy a block of data from user space, with less checking. * @to:   Destination address, in kernel space.
666  * @from: Source address, in user space.
667  * @n:    Number of bytes to copy.
668  *
669  * Context: User context only.  This function may sleep.
670  *
671  * Copy data from user space to kernel space.  Caller must check
672  * the specified block with access_ok() before calling this function.
673  *
674  * Returns number of bytes that could not be copied.
675  * On success, this will be zero.
676  *
677  * If some data could not be copied, this function will pad the copied
678  * data to the requested size using zero bytes.
679  */
680 #define __copy_from_user(to,from,n)                     \
681         __generic_copy_from_user_nocheck((to),(from),(n))
682
683 /**
684  * copy_from_user: - Copy a block of data from user space.
685  * @to:   Destination address, in kernel space.
686  * @from: Source address, in user space.
687  * @n:    Number of bytes to copy.
688  *
689  * Context: User context only.  This function may sleep.
690  *
691  * Copy data from user space to kernel space.
692  *
693  * Returns number of bytes that could not be copied.
694  * On success, this will be zero.
695  *
696  * If some data could not be copied, this function will pad the copied
697  * data to the requested size using zero bytes.
698  */
699 #define copy_from_user(to,from,n)                       \
700 ({                                                      \
701         might_sleep();                                  \
702 __generic_copy_from_user((to),(from),(n));      \
703 })
704
705 long __must_check strncpy_from_user(char *dst, const char __user *src,
706                                 long count);
707 long __must_check __strncpy_from_user(char *dst,
708                                 const char __user *src, long count);
709
710 /**
711  * __clear_user: - Zero a block of memory in user space, with less checking.
712  * @to:   Destination address, in user space.
713  * @n:    Number of bytes to zero.
714  *
715  * Zero a block of memory in user space.  Caller must check
716  * the specified block with access_ok() before calling this function.
717  *
718  * Returns number of bytes that could not be cleared.
719  * On success, this will be zero.
720  */
721 unsigned long __clear_user(void __user *mem, unsigned long len);
722
723 /**
724  * clear_user: - Zero a block of memory in user space.
725  * @to:   Destination address, in user space.
726  * @n:    Number of bytes to zero.
727  *
728  * Zero a block of memory in user space.  Caller must check
729  * the specified block with access_ok() before calling this function.
730  *
731  * Returns number of bytes that could not be cleared.
732  * On success, this will be zero.
733  */
734 unsigned long clear_user(void __user *mem, unsigned long len);
735
736 /**
737  * strlen_user: - Get the size of a string in user space.
738  * @str: The string to measure.
739  *
740  * Context: User context only.  This function may sleep.
741  *
742  * Get the size of a NUL-terminated string in user space.
743  *
744  * Returns the size of the string INCLUDING the terminating NUL.
745  * On exception, returns 0.
746  *
747  * If there is a limit on the length of a valid string, you may wish to
748  * consider using strnlen_user() instead.
749  */
750 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
751 long strnlen_user(const char __user *str, long n);
752
753 #endif /* _ASM_M32R_UACCESS_H */