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16#ifndef _XTENSA_UACCESS_H
17#define _XTENSA_UACCESS_H
18
19#include <linux/errno.h>
20
21#define VERIFY_READ 0
22#define VERIFY_WRITE 1
23
24#ifdef __ASSEMBLY__
25
26#include <asm/current.h>
27#include <asm/asm-offsets.h>
28#include <asm/processor.h>
29#include <asm/types.h>
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36
37#define KERNEL_DS 0
38#define USER_DS 1
39
40#define get_ds (KERNEL_DS)
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50 .macro get_fs ad, sp
51 GET_CURRENT(\ad,\sp)
52 l32i \ad, \ad, THREAD_CURRENT_DS
53 .endm
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65 .macro set_fs at, av, sp
66 GET_CURRENT(\at,\sp)
67 s32i \av, \at, THREAD_CURRENT_DS
68 .endm
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90#if ((KERNEL_DS != 0) || (USER_DS == 0))
91# error Assembly macro kernel_ok fails
92#endif
93 .macro kernel_ok at, sp, success
94 get_fs \at, \sp
95 beqz \at, \success
96 .endm
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121 .macro user_ok aa, as, at, error
122 movi \at, __XTENSA_UL_CONST(TASK_SIZE)
123 bgeu \as, \at, \error
124 sub \at, \at, \as
125 bgeu \aa, \at, \error
126 .endm
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151 .macro access_ok aa, as, at, sp, error
152 kernel_ok \at, \sp, .Laccess_ok_\@
153 user_ok \aa, \as, \at, \error
154.Laccess_ok_\@:
155 .endm
156
157#else
158
159#include <linux/sched.h>
160#include <asm/types.h>
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170
171#define KERNEL_DS ((mm_segment_t) { 0 })
172#define USER_DS ((mm_segment_t) { 1 })
173
174#define get_ds() (KERNEL_DS)
175#define get_fs() (current->thread.current_ds)
176#define set_fs(val) (current->thread.current_ds = (val))
177
178#define segment_eq(a,b) ((a).seg == (b).seg)
179
180#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
181#define __user_ok(addr,size) (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size)))
182#define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size)))
183#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))
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199#define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
200#define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
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207
208#define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
209#define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
210
211
212extern long __put_user_bad(void);
213
214#define __put_user_nocheck(x,ptr,size) \
215({ \
216 long __pu_err; \
217 __put_user_size((x),(ptr),(size),__pu_err); \
218 __pu_err; \
219})
220
221#define __put_user_check(x,ptr,size) \
222({ \
223 long __pu_err = -EFAULT; \
224 __typeof__(*(ptr)) *__pu_addr = (ptr); \
225 if (access_ok(VERIFY_WRITE,__pu_addr,size)) \
226 __put_user_size((x),__pu_addr,(size),__pu_err); \
227 __pu_err; \
228})
229
230#define __put_user_size(x,ptr,size,retval) \
231do { \
232 int __cb; \
233 retval = 0; \
234 switch (size) { \
235 case 1: __put_user_asm(x,ptr,retval,1,"s8i",__cb); break; \
236 case 2: __put_user_asm(x,ptr,retval,2,"s16i",__cb); break; \
237 case 4: __put_user_asm(x,ptr,retval,4,"s32i",__cb); break; \
238 case 8: { \
239 __typeof__(*ptr) __v64 = x; \
240 retval = __copy_to_user(ptr,&__v64,8); \
241 break; \
242 } \
243 default: __put_user_bad(); \
244 } \
245} while (0)
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269#define __check_align_1 ""
270
271#define __check_align_2 \
272 " _bbci.l %3, 0, 1f \n" \
273 " movi %0, %4 \n" \
274 " _j 2f \n"
275
276#define __check_align_4 \
277 " _bbsi.l %3, 0, 0f \n" \
278 " _bbci.l %3, 1, 1f \n" \
279 "0: movi %0, %4 \n" \
280 " _j 2f \n"
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291#define __put_user_asm(x, addr, err, align, insn, cb) \
292 __asm__ __volatile__( \
293 __check_align_##align \
294 "1: "insn" %2, %3, 0 \n" \
295 "2: \n" \
296 " .section .fixup,\"ax\" \n" \
297 " .align 4 \n" \
298 "4: \n" \
299 " .long 2b \n" \
300 "5: \n" \
301 " l32r %1, 4b \n" \
302 " movi %0, %4 \n" \
303 " jx %1 \n" \
304 " .previous \n" \
305 " .section __ex_table,\"a\" \n" \
306 " .long 1b, 5b \n" \
307 " .previous" \
308 :"=r" (err), "=r" (cb) \
309 :"r" ((int)(x)), "r" (addr), "i" (-EFAULT), "0" (err))
310
311#define __get_user_nocheck(x,ptr,size) \
312({ \
313 long __gu_err, __gu_val; \
314 __get_user_size(__gu_val,(ptr),(size),__gu_err); \
315 (x) = (__typeof__(*(ptr)))__gu_val; \
316 __gu_err; \
317})
318
319#define __get_user_check(x,ptr,size) \
320({ \
321 long __gu_err = -EFAULT, __gu_val = 0; \
322 const __typeof__(*(ptr)) *__gu_addr = (ptr); \
323 if (access_ok(VERIFY_READ,__gu_addr,size)) \
324 __get_user_size(__gu_val,__gu_addr,(size),__gu_err); \
325 (x) = (__typeof__(*(ptr)))__gu_val; \
326 __gu_err; \
327})
328
329extern long __get_user_bad(void);
330
331#define __get_user_size(x,ptr,size,retval) \
332do { \
333 int __cb; \
334 retval = 0; \
335 switch (size) { \
336 case 1: __get_user_asm(x,ptr,retval,1,"l8ui",__cb); break; \
337 case 2: __get_user_asm(x,ptr,retval,2,"l16ui",__cb); break; \
338 case 4: __get_user_asm(x,ptr,retval,4,"l32i",__cb); break; \
339 case 8: retval = __copy_from_user(&x,ptr,8); break; \
340 default: (x) = __get_user_bad(); \
341 } \
342} while (0)
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349#define __get_user_asm(x, addr, err, align, insn, cb) \
350 __asm__ __volatile__( \
351 __check_align_##align \
352 "1: "insn" %2, %3, 0 \n" \
353 "2: \n" \
354 " .section .fixup,\"ax\" \n" \
355 " .align 4 \n" \
356 "4: \n" \
357 " .long 2b \n" \
358 "5: \n" \
359 " l32r %1, 4b \n" \
360 " movi %2, 0 \n" \
361 " movi %0, %4 \n" \
362 " jx %1 \n" \
363 " .previous \n" \
364 " .section __ex_table,\"a\" \n" \
365 " .long 1b, 5b \n" \
366 " .previous" \
367 :"=r" (err), "=r" (cb), "=r" (x) \
368 :"r" (addr), "i" (-EFAULT), "0" (err))
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384extern unsigned __xtensa_copy_user(void *to, const void *from, unsigned n);
385#define __copy_user(to,from,size) __xtensa_copy_user(to,from,size)
386
387
388static inline unsigned long
389__generic_copy_from_user_nocheck(void *to, const void *from, unsigned long n)
390{
391 return __copy_user(to,from,n);
392}
393
394static inline unsigned long
395__generic_copy_to_user_nocheck(void *to, const void *from, unsigned long n)
396{
397 return __copy_user(to,from,n);
398}
399
400static inline unsigned long
401__generic_copy_to_user(void *to, const void *from, unsigned long n)
402{
403 prefetch(from);
404 if (access_ok(VERIFY_WRITE, to, n))
405 return __copy_user(to,from,n);
406 return n;
407}
408
409static inline unsigned long
410__generic_copy_from_user(void *to, const void *from, unsigned long n)
411{
412 prefetchw(to);
413 if (access_ok(VERIFY_READ, from, n))
414 return __copy_user(to,from,n);
415 else
416 memset(to, 0, n);
417 return n;
418}
419
420#define copy_to_user(to,from,n) __generic_copy_to_user((to),(from),(n))
421#define copy_from_user(to,from,n) __generic_copy_from_user((to),(from),(n))
422#define __copy_to_user(to,from,n) __generic_copy_to_user_nocheck((to),(from),(n))
423#define __copy_from_user(to,from,n) __generic_copy_from_user_nocheck((to),(from),(n))
424#define __copy_to_user_inatomic __copy_to_user
425#define __copy_from_user_inatomic __copy_from_user
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435static inline unsigned long
436__xtensa_clear_user(void *addr, unsigned long size)
437{
438 if ( ! memset(addr, 0, size) )
439 return size;
440 return 0;
441}
442
443static inline unsigned long
444clear_user(void *addr, unsigned long size)
445{
446 if (access_ok(VERIFY_WRITE, addr, size))
447 return __xtensa_clear_user(addr, size);
448 return size ? -EFAULT : 0;
449}
450
451#define __clear_user __xtensa_clear_user
452
453
454extern long __strncpy_user(char *, const char *, long);
455#define __strncpy_from_user __strncpy_user
456
457static inline long
458strncpy_from_user(char *dst, const char *src, long count)
459{
460 if (access_ok(VERIFY_READ, src, 1))
461 return __strncpy_from_user(dst, src, count);
462 return -EFAULT;
463}
464
465
466#define strlen_user(str) strnlen_user((str), TASK_SIZE - 1)
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471extern long __strnlen_user(const char *, long);
472
473static inline long strnlen_user(const char *str, long len)
474{
475 unsigned long top = __kernel_ok ? ~0UL : TASK_SIZE - 1;
476
477 if ((unsigned long)str > top)
478 return 0;
479 return __strnlen_user(str, len);
480}
481
482
483struct exception_table_entry
484{
485 unsigned long insn, fixup;
486};
487
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490extern unsigned long search_exception_table(unsigned long addr);
491extern void sort_exception_table(void);
492
493
494#define fixup_exception(map_reg, fixup_unit, pc) \
495({ \
496 fixup_unit; \
497})
498
499#endif
500#endif
501