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Linux 2.6.25-rc4
[linux-2.6/next.git] / arch / x86 / lib / usercopy_32.c
blobe849b9998b0e1577519a96f9f110893bfab804ca
1 /*
2 * User address space access functions.
3 * The non inlined parts of asm-i386/uaccess.h are here.
4 *
5 * Copyright 1997 Andi Kleen <ak@muc.de>
6 * Copyright 1997 Linus Torvalds
7 */
8 #include <linux/mm.h>
9 #include <linux/highmem.h>
10 #include <linux/blkdev.h>
11 #include <linux/module.h>
12 #include <linux/backing-dev.h>
13 #include <linux/interrupt.h>
14 #include <asm/uaccess.h>
15 #include <asm/mmx.h>
16
17 static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n)
18 {
19 #ifdef CONFIG_X86_INTEL_USERCOPY
20 if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask))
21 return 0;
22 #endif
23 return 1;
24 }
25 #define movsl_is_ok(a1,a2,n) \
26 __movsl_is_ok((unsigned long)(a1),(unsigned long)(a2),(n))
27
28 /*
29 * Copy a null terminated string from userspace.
30 */
31
32 #define __do_strncpy_from_user(dst,src,count,res) \
33 do { \
34 int __d0, __d1, __d2; \
35 might_sleep(); \
36 __asm__ __volatile__( \
37 " testl %1,%1\n" \
38 " jz 2f\n" \
39 "0: lodsb\n" \
40 " stosb\n" \
41 " testb %%al,%%al\n" \
42 " jz 1f\n" \
43 " decl %1\n" \
44 " jnz 0b\n" \
45 "1: subl %1,%0\n" \
46 "2:\n" \
47 ".section .fixup,\"ax\"\n" \
48 "3: movl %5,%0\n" \
49 " jmp 2b\n" \
50 ".previous\n" \
51 _ASM_EXTABLE(0b,3b) \
52 : "=d"(res), "=c"(count), "=&a" (__d0), "=&S" (__d1), \
53 "=&D" (__d2) \
54 : "i"(-EFAULT), "0"(count), "1"(count), "3"(src), "4"(dst) \
55 : "memory"); \
56 } while (0)
57
58 /**
59 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
60 * @dst: Destination address, in kernel space. This buffer must be at
61 * least @count bytes long.
62 * @src: Source address, in user space.
63 * @count: Maximum number of bytes to copy, including the trailing NUL.
64 *
65 * Copies a NUL-terminated string from userspace to kernel space.
66 * Caller must check the specified block with access_ok() before calling
67 * this function.
68 *
69 * On success, returns the length of the string (not including the trailing
70 * NUL).
71 *
72 * If access to userspace fails, returns -EFAULT (some data may have been
73 * copied).
74 *
75 * If @count is smaller than the length of the string, copies @count bytes
76 * and returns @count.
77 */
78 long
79 __strncpy_from_user(char *dst, const char __user *src, long count)
80 {
81 long res;
82 __do_strncpy_from_user(dst, src, count, res);
83 return res;
84 }
85 EXPORT_SYMBOL(__strncpy_from_user);
86
87 /**
88 * strncpy_from_user: - Copy a NUL terminated string from userspace.
89 * @dst: Destination address, in kernel space. This buffer must be at
90 * least @count bytes long.
91 * @src: Source address, in user space.
92 * @count: Maximum number of bytes to copy, including the trailing NUL.
93 *
94 * Copies a NUL-terminated string from userspace to kernel space.
95 *
96 * On success, returns the length of the string (not including the trailing
97 * NUL).
98 *
99 * If access to userspace fails, returns -EFAULT (some data may have been
100 * copied).
101 *
102 * If @count is smaller than the length of the string, copies @count bytes
103 * and returns @count.
104 */
105 long
106 strncpy_from_user(char *dst, const char __user *src, long count)
107 {
108 long res = -EFAULT;
109 if (access_ok(VERIFY_READ, src, 1))
110 __do_strncpy_from_user(dst, src, count, res);
111 return res;
112 }
113 EXPORT_SYMBOL(strncpy_from_user);
114
115 /*
116 * Zero Userspace
117 */
118
119 #define __do_clear_user(addr,size) \
120 do { \
121 int __d0; \
122 might_sleep(); \
123 __asm__ __volatile__( \
124 "0: rep; stosl\n" \
125 " movl %2,%0\n" \
126 "1: rep; stosb\n" \
127 "2:\n" \
128 ".section .fixup,\"ax\"\n" \
129 "3: lea 0(%2,%0,4),%0\n" \
130 " jmp 2b\n" \
131 ".previous\n" \
132 _ASM_EXTABLE(0b,3b) \
133 _ASM_EXTABLE(1b,2b) \
134 : "=&c"(size), "=&D" (__d0) \
135 : "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0)); \
136 } while (0)
137
138 /**
139 * clear_user: - Zero a block of memory in user space.
140 * @to: Destination address, in user space.
141 * @n: Number of bytes to zero.
142 *
143 * Zero a block of memory in user space.
144 *
145 * Returns number of bytes that could not be cleared.
146 * On success, this will be zero.
147 */
148 unsigned long
149 clear_user(void __user *to, unsigned long n)
150 {
151 might_sleep();
152 if (access_ok(VERIFY_WRITE, to, n))
153 __do_clear_user(to, n);
154 return n;
155 }
156 EXPORT_SYMBOL(clear_user);
157
158 /**
159 * __clear_user: - Zero a block of memory in user space, with less checking.
160 * @to: Destination address, in user space.
161 * @n: Number of bytes to zero.
162 *
163 * Zero a block of memory in user space. Caller must check
164 * the specified block with access_ok() before calling this function.
165 *
166 * Returns number of bytes that could not be cleared.
167 * On success, this will be zero.
168 */
169 unsigned long
170 __clear_user(void __user *to, unsigned long n)
171 {
172 __do_clear_user(to, n);
173 return n;
174 }
175 EXPORT_SYMBOL(__clear_user);
176
177 /**
178 * strnlen_user: - Get the size of a string in user space.
179 * @s: The string to measure.
180 * @n: The maximum valid length
181 *
182 * Get the size of a NUL-terminated string in user space.
183 *
184 * Returns the size of the string INCLUDING the terminating NUL.
185 * On exception, returns 0.
186 * If the string is too long, returns a value greater than @n.
187 */
188 long strnlen_user(const char __user *s, long n)
189 {
190 unsigned long mask = -__addr_ok(s);
191 unsigned long res, tmp;
192
193 might_sleep();
194
195 __asm__ __volatile__(
196 " testl %0, %0\n"
197 " jz 3f\n"
198 " andl %0,%%ecx\n"
199 "0: repne; scasb\n"
200 " setne %%al\n"
201 " subl %%ecx,%0\n"
202 " addl %0,%%eax\n"
203 "1:\n"
204 ".section .fixup,\"ax\"\n"
205 "2: xorl %%eax,%%eax\n"
206 " jmp 1b\n"
207 "3: movb $1,%%al\n"
208 " jmp 1b\n"
209 ".previous\n"
210 ".section __ex_table,\"a\"\n"
211 " .align 4\n"
212 " .long 0b,2b\n"
213 ".previous"
214 :"=r" (n), "=D" (s), "=a" (res), "=c" (tmp)
215 :"0" (n), "1" (s), "2" (0), "3" (mask)
216 :"cc");
217 return res & mask;
218 }
219 EXPORT_SYMBOL(strnlen_user);
220
221 #ifdef CONFIG_X86_INTEL_USERCOPY
222 static unsigned long
223 __copy_user_intel(void __user *to, const void *from, unsigned long size)
224 {
225 int d0, d1;
226 __asm__ __volatile__(
227 " .align 2,0x90\n"
228 "1: movl 32(%4), %%eax\n"
229 " cmpl $67, %0\n"
230 " jbe 3f\n"
231 "2: movl 64(%4), %%eax\n"
232 " .align 2,0x90\n"
233 "3: movl 0(%4), %%eax\n"
234 "4: movl 4(%4), %%edx\n"
235 "5: movl %%eax, 0(%3)\n"
236 "6: movl %%edx, 4(%3)\n"
237 "7: movl 8(%4), %%eax\n"
238 "8: movl 12(%4),%%edx\n"
239 "9: movl %%eax, 8(%3)\n"
240 "10: movl %%edx, 12(%3)\n"
241 "11: movl 16(%4), %%eax\n"
242 "12: movl 20(%4), %%edx\n"
243 "13: movl %%eax, 16(%3)\n"
244 "14: movl %%edx, 20(%3)\n"
245 "15: movl 24(%4), %%eax\n"
246 "16: movl 28(%4), %%edx\n"
247 "17: movl %%eax, 24(%3)\n"
248 "18: movl %%edx, 28(%3)\n"
249 "19: movl 32(%4), %%eax\n"
250 "20: movl 36(%4), %%edx\n"
251 "21: movl %%eax, 32(%3)\n"
252 "22: movl %%edx, 36(%3)\n"
253 "23: movl 40(%4), %%eax\n"
254 "24: movl 44(%4), %%edx\n"
255 "25: movl %%eax, 40(%3)\n"
256 "26: movl %%edx, 44(%3)\n"
257 "27: movl 48(%4), %%eax\n"
258 "28: movl 52(%4), %%edx\n"
259 "29: movl %%eax, 48(%3)\n"
260 "30: movl %%edx, 52(%3)\n"
261 "31: movl 56(%4), %%eax\n"
262 "32: movl 60(%4), %%edx\n"
263 "33: movl %%eax, 56(%3)\n"
264 "34: movl %%edx, 60(%3)\n"
265 " addl $-64, %0\n"
266 " addl $64, %4\n"
267 " addl $64, %3\n"
268 " cmpl $63, %0\n"
269 " ja 1b\n"
270 "35: movl %0, %%eax\n"
271 " shrl $2, %0\n"
272 " andl $3, %%eax\n"
273 " cld\n"
274 "99: rep; movsl\n"
275 "36: movl %%eax, %0\n"
276 "37: rep; movsb\n"
277 "100:\n"
278 ".section .fixup,\"ax\"\n"
279 "101: lea 0(%%eax,%0,4),%0\n"
280 " jmp 100b\n"
281 ".previous\n"
282 ".section __ex_table,\"a\"\n"
283 " .align 4\n"
284 " .long 1b,100b\n"
285 " .long 2b,100b\n"
286 " .long 3b,100b\n"
287 " .long 4b,100b\n"
288 " .long 5b,100b\n"
289 " .long 6b,100b\n"
290 " .long 7b,100b\n"
291 " .long 8b,100b\n"
292 " .long 9b,100b\n"
293 " .long 10b,100b\n"
294 " .long 11b,100b\n"
295 " .long 12b,100b\n"
296 " .long 13b,100b\n"
297 " .long 14b,100b\n"
298 " .long 15b,100b\n"
299 " .long 16b,100b\n"
300 " .long 17b,100b\n"
301 " .long 18b,100b\n"
302 " .long 19b,100b\n"
303 " .long 20b,100b\n"
304 " .long 21b,100b\n"
305 " .long 22b,100b\n"
306 " .long 23b,100b\n"
307 " .long 24b,100b\n"
308 " .long 25b,100b\n"
309 " .long 26b,100b\n"
310 " .long 27b,100b\n"
311 " .long 28b,100b\n"
312 " .long 29b,100b\n"
313 " .long 30b,100b\n"
314 " .long 31b,100b\n"
315 " .long 32b,100b\n"
316 " .long 33b,100b\n"
317 " .long 34b,100b\n"
318 " .long 35b,100b\n"
319 " .long 36b,100b\n"
320 " .long 37b,100b\n"
321 " .long 99b,101b\n"
322 ".previous"
323 : "=&c"(size), "=&D" (d0), "=&S" (d1)
324 : "1"(to), "2"(from), "0"(size)
325 : "eax", "edx", "memory");
326 return size;
327 }
328
329 static unsigned long
330 __copy_user_zeroing_intel(void *to, const void __user *from, unsigned long size)
331 {
332 int d0, d1;
333 __asm__ __volatile__(
334 " .align 2,0x90\n"
335 "0: movl 32(%4), %%eax\n"
336 " cmpl $67, %0\n"
337 " jbe 2f\n"
338 "1: movl 64(%4), %%eax\n"
339 " .align 2,0x90\n"
340 "2: movl 0(%4), %%eax\n"
341 "21: movl 4(%4), %%edx\n"
342 " movl %%eax, 0(%3)\n"
343 " movl %%edx, 4(%3)\n"
344 "3: movl 8(%4), %%eax\n"
345 "31: movl 12(%4),%%edx\n"
346 " movl %%eax, 8(%3)\n"
347 " movl %%edx, 12(%3)\n"
348 "4: movl 16(%4), %%eax\n"
349 "41: movl 20(%4), %%edx\n"
350 " movl %%eax, 16(%3)\n"
351 " movl %%edx, 20(%3)\n"
352 "10: movl 24(%4), %%eax\n"
353 "51: movl 28(%4), %%edx\n"
354 " movl %%eax, 24(%3)\n"
355 " movl %%edx, 28(%3)\n"
356 "11: movl 32(%4), %%eax\n"
357 "61: movl 36(%4), %%edx\n"
358 " movl %%eax, 32(%3)\n"
359 " movl %%edx, 36(%3)\n"
360 "12: movl 40(%4), %%eax\n"
361 "71: movl 44(%4), %%edx\n"
362 " movl %%eax, 40(%3)\n"
363 " movl %%edx, 44(%3)\n"
364 "13: movl 48(%4), %%eax\n"
365 "81: movl 52(%4), %%edx\n"
366 " movl %%eax, 48(%3)\n"
367 " movl %%edx, 52(%3)\n"
368 "14: movl 56(%4), %%eax\n"
369 "91: movl 60(%4), %%edx\n"
370 " movl %%eax, 56(%3)\n"
371 " movl %%edx, 60(%3)\n"
372 " addl $-64, %0\n"
373 " addl $64, %4\n"
374 " addl $64, %3\n"
375 " cmpl $63, %0\n"
376 " ja 0b\n"
377 "5: movl %0, %%eax\n"
378 " shrl $2, %0\n"
379 " andl $3, %%eax\n"
380 " cld\n"
381 "6: rep; movsl\n"
382 " movl %%eax,%0\n"
383 "7: rep; movsb\n"
384 "8:\n"
385 ".section .fixup,\"ax\"\n"
386 "9: lea 0(%%eax,%0,4),%0\n"
387 "16: pushl %0\n"
388 " pushl %%eax\n"
389 " xorl %%eax,%%eax\n"
390 " rep; stosb\n"
391 " popl %%eax\n"
392 " popl %0\n"
393 " jmp 8b\n"
394 ".previous\n"
395 ".section __ex_table,\"a\"\n"
396 " .align 4\n"
397 " .long 0b,16b\n"
398 " .long 1b,16b\n"
399 " .long 2b,16b\n"
400 " .long 21b,16b\n"
401 " .long 3b,16b\n"
402 " .long 31b,16b\n"
403 " .long 4b,16b\n"
404 " .long 41b,16b\n"
405 " .long 10b,16b\n"
406 " .long 51b,16b\n"
407 " .long 11b,16b\n"
408 " .long 61b,16b\n"
409 " .long 12b,16b\n"
410 " .long 71b,16b\n"
411 " .long 13b,16b\n"
412 " .long 81b,16b\n"
413 " .long 14b,16b\n"
414 " .long 91b,16b\n"
415 " .long 6b,9b\n"
416 " .long 7b,16b\n"
417 ".previous"
418 : "=&c"(size), "=&D" (d0), "=&S" (d1)
419 : "1"(to), "2"(from), "0"(size)
420 : "eax", "edx", "memory");
421 return size;
422 }
423
424 /*
425 * Non Temporal Hint version of __copy_user_zeroing_intel. It is cache aware.
426 * hyoshiok@miraclelinux.com
427 */
428
429 static unsigned long __copy_user_zeroing_intel_nocache(void *to,
430 const void __user *from, unsigned long size)
431 {
432 int d0, d1;
433
434 __asm__ __volatile__(
435 " .align 2,0x90\n"
436 "0: movl 32(%4), %%eax\n"
437 " cmpl $67, %0\n"
438 " jbe 2f\n"
439 "1: movl 64(%4), %%eax\n"
440 " .align 2,0x90\n"
441 "2: movl 0(%4), %%eax\n"
442 "21: movl 4(%4), %%edx\n"
443 " movnti %%eax, 0(%3)\n"
444 " movnti %%edx, 4(%3)\n"
445 "3: movl 8(%4), %%eax\n"
446 "31: movl 12(%4),%%edx\n"
447 " movnti %%eax, 8(%3)\n"
448 " movnti %%edx, 12(%3)\n"
449 "4: movl 16(%4), %%eax\n"
450 "41: movl 20(%4), %%edx\n"
451 " movnti %%eax, 16(%3)\n"
452 " movnti %%edx, 20(%3)\n"
453 "10: movl 24(%4), %%eax\n"
454 "51: movl 28(%4), %%edx\n"
455 " movnti %%eax, 24(%3)\n"
456 " movnti %%edx, 28(%3)\n"
457 "11: movl 32(%4), %%eax\n"
458 "61: movl 36(%4), %%edx\n"
459 " movnti %%eax, 32(%3)\n"
460 " movnti %%edx, 36(%3)\n"
461 "12: movl 40(%4), %%eax\n"
462 "71: movl 44(%4), %%edx\n"
463 " movnti %%eax, 40(%3)\n"
464 " movnti %%edx, 44(%3)\n"
465 "13: movl 48(%4), %%eax\n"
466 "81: movl 52(%4), %%edx\n"
467 " movnti %%eax, 48(%3)\n"
468 " movnti %%edx, 52(%3)\n"
469 "14: movl 56(%4), %%eax\n"
470 "91: movl 60(%4), %%edx\n"
471 " movnti %%eax, 56(%3)\n"
472 " movnti %%edx, 60(%3)\n"
473 " addl $-64, %0\n"
474 " addl $64, %4\n"
475 " addl $64, %3\n"
476 " cmpl $63, %0\n"
477 " ja 0b\n"
478 " sfence \n"
479 "5: movl %0, %%eax\n"
480 " shrl $2, %0\n"
481 " andl $3, %%eax\n"
482 " cld\n"
483 "6: rep; movsl\n"
484 " movl %%eax,%0\n"
485 "7: rep; movsb\n"
486 "8:\n"
487 ".section .fixup,\"ax\"\n"
488 "9: lea 0(%%eax,%0,4),%0\n"
489 "16: pushl %0\n"
490 " pushl %%eax\n"
491 " xorl %%eax,%%eax\n"
492 " rep; stosb\n"
493 " popl %%eax\n"
494 " popl %0\n"
495 " jmp 8b\n"
496 ".previous\n"
497 ".section __ex_table,\"a\"\n"
498 " .align 4\n"
499 " .long 0b,16b\n"
500 " .long 1b,16b\n"
501 " .long 2b,16b\n"
502 " .long 21b,16b\n"
503 " .long 3b,16b\n"
504 " .long 31b,16b\n"
505 " .long 4b,16b\n"
506 " .long 41b,16b\n"
507 " .long 10b,16b\n"
508 " .long 51b,16b\n"
509 " .long 11b,16b\n"
510 " .long 61b,16b\n"
511 " .long 12b,16b\n"
512 " .long 71b,16b\n"
513 " .long 13b,16b\n"
514 " .long 81b,16b\n"
515 " .long 14b,16b\n"
516 " .long 91b,16b\n"
517 " .long 6b,9b\n"
518 " .long 7b,16b\n"
519 ".previous"
520 : "=&c"(size), "=&D" (d0), "=&S" (d1)
521 : "1"(to), "2"(from), "0"(size)
522 : "eax", "edx", "memory");
523 return size;
524 }
525
526 static unsigned long __copy_user_intel_nocache(void *to,
527 const void __user *from, unsigned long size)
528 {
529 int d0, d1;
530
531 __asm__ __volatile__(
532 " .align 2,0x90\n"
533 "0: movl 32(%4), %%eax\n"
534 " cmpl $67, %0\n"
535 " jbe 2f\n"
536 "1: movl 64(%4), %%eax\n"
537 " .align 2,0x90\n"
538 "2: movl 0(%4), %%eax\n"
539 "21: movl 4(%4), %%edx\n"
540 " movnti %%eax, 0(%3)\n"
541 " movnti %%edx, 4(%3)\n"
542 "3: movl 8(%4), %%eax\n"
543 "31: movl 12(%4),%%edx\n"
544 " movnti %%eax, 8(%3)\n"
545 " movnti %%edx, 12(%3)\n"
546 "4: movl 16(%4), %%eax\n"
547 "41: movl 20(%4), %%edx\n"
548 " movnti %%eax, 16(%3)\n"
549 " movnti %%edx, 20(%3)\n"
550 "10: movl 24(%4), %%eax\n"
551 "51: movl 28(%4), %%edx\n"
552 " movnti %%eax, 24(%3)\n"
553 " movnti %%edx, 28(%3)\n"
554 "11: movl 32(%4), %%eax\n"
555 "61: movl 36(%4), %%edx\n"
556 " movnti %%eax, 32(%3)\n"
557 " movnti %%edx, 36(%3)\n"
558 "12: movl 40(%4), %%eax\n"
559 "71: movl 44(%4), %%edx\n"
560 " movnti %%eax, 40(%3)\n"
561 " movnti %%edx, 44(%3)\n"
562 "13: movl 48(%4), %%eax\n"
563 "81: movl 52(%4), %%edx\n"
564 " movnti %%eax, 48(%3)\n"
565 " movnti %%edx, 52(%3)\n"
566 "14: movl 56(%4), %%eax\n"
567 "91: movl 60(%4), %%edx\n"
568 " movnti %%eax, 56(%3)\n"
569 " movnti %%edx, 60(%3)\n"
570 " addl $-64, %0\n"
571 " addl $64, %4\n"
572 " addl $64, %3\n"
573 " cmpl $63, %0\n"
574 " ja 0b\n"
575 " sfence \n"
576 "5: movl %0, %%eax\n"
577 " shrl $2, %0\n"
578 " andl $3, %%eax\n"
579 " cld\n"
580 "6: rep; movsl\n"
581 " movl %%eax,%0\n"
582 "7: rep; movsb\n"
583 "8:\n"
584 ".section .fixup,\"ax\"\n"
585 "9: lea 0(%%eax,%0,4),%0\n"
586 "16: jmp 8b\n"
587 ".previous\n"
588 ".section __ex_table,\"a\"\n"
589 " .align 4\n"
590 " .long 0b,16b\n"
591 " .long 1b,16b\n"
592 " .long 2b,16b\n"
593 " .long 21b,16b\n"
594 " .long 3b,16b\n"
595 " .long 31b,16b\n"
596 " .long 4b,16b\n"
597 " .long 41b,16b\n"
598 " .long 10b,16b\n"
599 " .long 51b,16b\n"
600 " .long 11b,16b\n"
601 " .long 61b,16b\n"
602 " .long 12b,16b\n"
603 " .long 71b,16b\n"
604 " .long 13b,16b\n"
605 " .long 81b,16b\n"
606 " .long 14b,16b\n"
607 " .long 91b,16b\n"
608 " .long 6b,9b\n"
609 " .long 7b,16b\n"
610 ".previous"
611 : "=&c"(size), "=&D" (d0), "=&S" (d1)
612 : "1"(to), "2"(from), "0"(size)
613 : "eax", "edx", "memory");
614 return size;
615 }
616
617 #else
618
619 /*
620 * Leave these declared but undefined. They should not be any references to
621 * them
622 */
623 unsigned long __copy_user_zeroing_intel(void *to, const void __user *from,
624 unsigned long size);
625 unsigned long __copy_user_intel(void __user *to, const void *from,
626 unsigned long size);
627 unsigned long __copy_user_zeroing_intel_nocache(void *to,
628 const void __user *from, unsigned long size);
629 #endif /* CONFIG_X86_INTEL_USERCOPY */
630
631 /* Generic arbitrary sized copy. */
632 #define __copy_user(to,from,size) \
633 do { \
634 int __d0, __d1, __d2; \
635 __asm__ __volatile__( \
636 " cmp $7,%0\n" \
637 " jbe 1f\n" \
638 " movl %1,%0\n" \
639 " negl %0\n" \
640 " andl $7,%0\n" \
641 " subl %0,%3\n" \
642 "4: rep; movsb\n" \
643 " movl %3,%0\n" \
644 " shrl $2,%0\n" \
645 " andl $3,%3\n" \
646 " .align 2,0x90\n" \
647 "0: rep; movsl\n" \
648 " movl %3,%0\n" \
649 "1: rep; movsb\n" \
650 "2:\n" \
651 ".section .fixup,\"ax\"\n" \
652 "5: addl %3,%0\n" \
653 " jmp 2b\n" \
654 "3: lea 0(%3,%0,4),%0\n" \
655 " jmp 2b\n" \
656 ".previous\n" \
657 ".section __ex_table,\"a\"\n" \
658 " .align 4\n" \
659 " .long 4b,5b\n" \
660 " .long 0b,3b\n" \
661 " .long 1b,2b\n" \
662 ".previous" \
663 : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \
664 : "3"(size), "0"(size), "1"(to), "2"(from) \
665 : "memory"); \
666 } while (0)
667
668 #define __copy_user_zeroing(to,from,size) \
669 do { \
670 int __d0, __d1, __d2; \
671 __asm__ __volatile__( \
672 " cmp $7,%0\n" \
673 " jbe 1f\n" \
674 " movl %1,%0\n" \
675 " negl %0\n" \
676 " andl $7,%0\n" \
677 " subl %0,%3\n" \
678 "4: rep; movsb\n" \
679 " movl %3,%0\n" \
680 " shrl $2,%0\n" \
681 " andl $3,%3\n" \
682 " .align 2,0x90\n" \
683 "0: rep; movsl\n" \
684 " movl %3,%0\n" \
685 "1: rep; movsb\n" \
686 "2:\n" \
687 ".section .fixup,\"ax\"\n" \
688 "5: addl %3,%0\n" \
689 " jmp 6f\n" \
690 "3: lea 0(%3,%0,4),%0\n" \
691 "6: pushl %0\n" \
692 " pushl %%eax\n" \
693 " xorl %%eax,%%eax\n" \
694 " rep; stosb\n" \
695 " popl %%eax\n" \
696 " popl %0\n" \
697 " jmp 2b\n" \
698 ".previous\n" \
699 ".section __ex_table,\"a\"\n" \
700 " .align 4\n" \
701 " .long 4b,5b\n" \
702 " .long 0b,3b\n" \
703 " .long 1b,6b\n" \
704 ".previous" \
705 : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \
706 : "3"(size), "0"(size), "1"(to), "2"(from) \
707 : "memory"); \
708 } while (0)
709
710 unsigned long __copy_to_user_ll(void __user *to, const void *from,
711 unsigned long n)
712 {
713 #ifndef CONFIG_X86_WP_WORKS_OK
714 if (unlikely(boot_cpu_data.wp_works_ok == 0) &&
715 ((unsigned long )to) < TASK_SIZE) {
716 /*
717 * When we are in an atomic section (see
718 * mm/filemap.c:file_read_actor), return the full
719 * length to take the slow path.
720 */
721 if (in_atomic())
722 return n;
723
724 /*
725 * CPU does not honor the WP bit when writing
726 * from supervisory mode, and due to preemption or SMP,
727 * the page tables can change at any time.
728 * Do it manually. Manfred <manfred@colorfullife.com>
729 */
730 while (n) {
731 unsigned long offset = ((unsigned long)to)%PAGE_SIZE;
732 unsigned long len = PAGE_SIZE - offset;
733 int retval;
734 struct page *pg;
735 void *maddr;
736
737 if (len > n)
738 len = n;
739
740 survive:
741 down_read(&current->mm->mmap_sem);
742 retval = get_user_pages(current, current->mm,
743 (unsigned long )to, 1, 1, 0, &pg, NULL);
744
745 if (retval == -ENOMEM && is_global_init(current)) {
746 up_read(&current->mm->mmap_sem);
747 congestion_wait(WRITE, HZ/50);
748 goto survive;
749 }
750
751 if (retval != 1) {
752 up_read(&current->mm->mmap_sem);
753 break;
754 }
755
756 maddr = kmap_atomic(pg, KM_USER0);
757 memcpy(maddr + offset, from, len);
758 kunmap_atomic(maddr, KM_USER0);
759 set_page_dirty_lock(pg);
760 put_page(pg);
761 up_read(&current->mm->mmap_sem);
762
763 from += len;
764 to += len;
765 n -= len;
766 }
767 return n;
768 }
769 #endif
770 if (movsl_is_ok(to, from, n))
771 __copy_user(to, from, n);
772 else
773 n = __copy_user_intel(to, from, n);
774 return n;
775 }
776 EXPORT_SYMBOL(__copy_to_user_ll);
777
778 unsigned long __copy_from_user_ll(void *to, const void __user *from,
779 unsigned long n)
780 {
781 if (movsl_is_ok(to, from, n))
782 __copy_user_zeroing(to, from, n);
783 else
784 n = __copy_user_zeroing_intel(to, from, n);
785 return n;
786 }
787 EXPORT_SYMBOL(__copy_from_user_ll);
788
789 unsigned long __copy_from_user_ll_nozero(void *to, const void __user *from,
790 unsigned long n)
791 {
792 if (movsl_is_ok(to, from, n))
793 __copy_user(to, from, n);
794 else
795 n = __copy_user_intel((void __user *)to,
796 (const void *)from, n);
797 return n;
798 }
799 EXPORT_SYMBOL(__copy_from_user_ll_nozero);
800
801 unsigned long __copy_from_user_ll_nocache(void *to, const void __user *from,
802 unsigned long n)
803 {
804 #ifdef CONFIG_X86_INTEL_USERCOPY
805 if ( n > 64 && cpu_has_xmm2)
806 n = __copy_user_zeroing_intel_nocache(to, from, n);
807 else
808 __copy_user_zeroing(to, from, n);
809 #else
810 __copy_user_zeroing(to, from, n);
811 #endif
812 return n;
813 }
814 EXPORT_SYMBOL(__copy_from_user_ll_nocache);
815
816 unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
817 unsigned long n)
818 {
819 #ifdef CONFIG_X86_INTEL_USERCOPY
820 if ( n > 64 && cpu_has_xmm2)
821 n = __copy_user_intel_nocache(to, from, n);
822 else
823 __copy_user(to, from, n);
824 #else
825 __copy_user(to, from, n);
826 #endif
827 return n;
828 }
829 EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero);
830
831 /**
832 * copy_to_user: - Copy a block of data into user space.
833 * @to: Destination address, in user space.
834 * @from: Source address, in kernel space.
835 * @n: Number of bytes to copy.
836 *
837 * Context: User context only. This function may sleep.
838 *
839 * Copy data from kernel space to user space.
840 *
841 * Returns number of bytes that could not be copied.
842 * On success, this will be zero.
843 */
844 unsigned long
845 copy_to_user(void __user *to, const void *from, unsigned long n)
846 {
847 if (access_ok(VERIFY_WRITE, to, n))
848 n = __copy_to_user(to, from, n);
849 return n;
850 }
851 EXPORT_SYMBOL(copy_to_user);
852
853 /**
854 * copy_from_user: - Copy a block of data from user space.
855 * @to: Destination address, in kernel space.
856 * @from: Source address, in user space.
857 * @n: Number of bytes to copy.
858 *
859 * Context: User context only. This function may sleep.
860 *
861 * Copy data from user space to kernel space.
862 *
863 * Returns number of bytes that could not be copied.
864 * On success, this will be zero.
865 *
866 * If some data could not be copied, this function will pad the copied
867 * data to the requested size using zero bytes.
868 */
869 unsigned long
870 copy_from_user(void *to, const void __user *from, unsigned long n)
871 {
872 if (access_ok(VERIFY_READ, from, n))
873 n = __copy_from_user(to, from, n);
874 else
875 memset(to, 0, n);
876 return n;
877 }
878 EXPORT_SYMBOL(copy_from_user);
linux-next