| blob | d3ed0636c00859e3f5e9c34d916981b4d42a36ad |
1 /*
2 * linux/arch/arm/lib/uaccess.S
3 *
4 * Copyright (C) 1995, 1996,1997,1998 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Routines to block copy data to/from user memory
11 * These are highly optimised both for the 4k page size
12 * and for various alignments.
13 */
14 #include <linux/linkage.h>
15 #include <asm/assembler.h>
16 #include <asm/errno.h>
18 .text
20 #define PAGE_SHIFT 12
22 /* Prototype: int __arch_copy_to_user(void *to, const char *from, size_t n)
23 * Purpose : copy a block to user memory from kernel memory
24 * Params : to - user memory
25 * : from - kernel memory
26 * : n - number of bytes to copy
27 * Returns : Number of bytes NOT copied.
28 */
30 .c2u_dest_not_aligned:
31 rsb ip, ip, #4
32 cmp ip, #2
33 ldrb r3, [r1], #1
34 USER( strbt r3, [r0], #1) @ May fault
35 ldrgeb r3, [r1], #1
36 USER( strgebt r3, [r0], #1) @ May fault
37 ldrgtb r3, [r1], #1
38 USER( strgtbt r3, [r0], #1) @ May fault
39 sub r2, r2, ip
40 b .c2u_dest_aligned
42 ENTRY(__arch_copy_to_user)
43 stmfd sp!, {r2, r4 - r7, lr}
44 cmp r2, #4
45 blt .c2u_not_enough
46 PLD( pld [r1, #0] )
47 PLD( pld [r0, #0] )
48 ands ip, r0, #3
49 bne .c2u_dest_not_aligned
50 .c2u_dest_aligned:
52 ands ip, r1, #3
53 bne .c2u_src_not_aligned
54 /*
55 * Seeing as there has to be at least 8 bytes to copy, we can
56 * copy one word, and force a user-mode page fault...
57 */
59 .c2u_0fupi: subs r2, r2, #4
60 addmi ip, r2, #4
61 bmi .c2u_0nowords
62 ldr r3, [r1], #4
63 USER( strt r3, [r0], #4) @ May fault
64 mov ip, r0, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
65 rsb ip, ip, #0
66 movs ip, ip, lsr #32 - PAGE_SHIFT
67 beq .c2u_0fupi
68 /*
69 * ip = max no. of bytes to copy before needing another "strt" insn
70 */
71 cmp r2, ip
72 movlt ip, r2
73 sub r2, r2, ip
74 subs ip, ip, #32
75 blt .c2u_0rem8lp
76 PLD( pld [r1, #28] )
77 PLD( pld [r0, #28] )
78 PLD( subs ip, ip, #64 )
79 PLD( blt .c2u_0cpynopld )
80 PLD( pld [r1, #60] )
81 PLD( pld [r0, #60] )
83 .c2u_0cpy8lp:
84 PLD( pld [r1, #92] )
85 PLD( pld [r0, #92] )
86 .c2u_0cpynopld: ldmia r1!, {r3 - r6}
87 stmia r0!, {r3 - r6} @ Shouldnt fault
88 ldmia r1!, {r3 - r6}
89 subs ip, ip, #32
90 stmia r0!, {r3 - r6} @ Shouldnt fault
91 bpl .c2u_0cpy8lp
92 PLD( cmn ip, #64 )
93 PLD( bge .c2u_0cpynopld )
94 PLD( add ip, ip, #64 )
96 .c2u_0rem8lp: cmn ip, #16
97 ldmgeia r1!, {r3 - r6}
98 stmgeia r0!, {r3 - r6} @ Shouldnt fault
99 tst ip, #8
100 ldmneia r1!, {r3 - r4}
101 stmneia r0!, {r3 - r4} @ Shouldnt fault
102 tst ip, #4
103 ldrne r3, [r1], #4
104 strnet r3, [r0], #4 @ Shouldnt fault
105 ands ip, ip, #3
106 beq .c2u_0fupi
107 .c2u_0nowords: teq ip, #0
108 beq .c2u_finished
109 .c2u_nowords: cmp ip, #2
110 ldrb r3, [r1], #1
111 USER( strbt r3, [r0], #1) @ May fault
112 ldrgeb r3, [r1], #1
113 USER( strgebt r3, [r0], #1) @ May fault
114 ldrgtb r3, [r1], #1
115 USER( strgtbt r3, [r0], #1) @ May fault
116 b .c2u_finished
118 .c2u_not_enough:
119 movs ip, r2
120 bne .c2u_nowords
121 .c2u_finished: mov r0, #0
122 LOADREGS(fd,sp!,{r2, r4 - r7, pc})
124 .c2u_src_not_aligned:
125 bic r1, r1, #3
126 ldr r7, [r1], #4
127 cmp ip, #2
128 bgt .c2u_3fupi
129 beq .c2u_2fupi
130 .c2u_1fupi: subs r2, r2, #4
131 addmi ip, r2, #4
132 bmi .c2u_1nowords
133 mov r3, r7, pull #8
134 ldr r7, [r1], #4
135 orr r3, r3, r7, push #24
136 USER( strt r3, [r0], #4) @ May fault
137 mov ip, r0, lsl #32 - PAGE_SHIFT
138 rsb ip, ip, #0
139 movs ip, ip, lsr #32 - PAGE_SHIFT
140 beq .c2u_1fupi
141 cmp r2, ip
142 movlt ip, r2
143 sub r2, r2, ip
144 subs ip, ip, #16
145 blt .c2u_1rem8lp
146 PLD( pld [r1, #12] )
147 PLD( pld [r0, #12] )
148 PLD( subs ip, ip, #32 )
149 PLD( blt .c2u_1cpynopld )
150 PLD( pld [r1, #28] )
151 PLD( pld [r0, #28] )
153 .c2u_1cpy8lp:
154 PLD( pld [r1, #44] )
155 PLD( pld [r0, #44] )
156 .c2u_1cpynopld: mov r3, r7, pull #8
157 ldmia r1!, {r4 - r7}
158 subs ip, ip, #16
159 orr r3, r3, r4, push #24
160 mov r4, r4, pull #8
161 orr r4, r4, r5, push #24
162 mov r5, r5, pull #8
163 orr r5, r5, r6, push #24
164 mov r6, r6, pull #8
165 orr r6, r6, r7, push #24
166 stmia r0!, {r3 - r6} @ Shouldnt fault
167 bpl .c2u_1cpy8lp
168 PLD( cmn ip, #32 )
169 PLD( bge .c2u_1cpynopld )
170 PLD( add ip, ip, #32 )
172 .c2u_1rem8lp: tst ip, #8
173 movne r3, r7, pull #8
174 ldmneia r1!, {r4, r7}
175 orrne r3, r3, r4, push #24
176 movne r4, r4, pull #8
177 orrne r4, r4, r7, push #24
178 stmneia r0!, {r3 - r4} @ Shouldnt fault
179 tst ip, #4
180 movne r3, r7, pull #8
181 ldrne r7, [r1], #4
182 orrne r3, r3, r7, push #24
183 strnet r3, [r0], #4 @ Shouldnt fault
184 ands ip, ip, #3
185 beq .c2u_1fupi
186 .c2u_1nowords: mov r3, r7, get_byte_1
187 teq ip, #0
188 beq .c2u_finished
189 cmp ip, #2
190 USER( strbt r3, [r0], #1) @ May fault
191 movge r3, r7, get_byte_2
192 USER( strgebt r3, [r0], #1) @ May fault
193 movgt r3, r7, get_byte_3
194 USER( strgtbt r3, [r0], #1) @ May fault
195 b .c2u_finished
197 .c2u_2fupi: subs r2, r2, #4
198 addmi ip, r2, #4
199 bmi .c2u_2nowords
200 mov r3, r7, pull #16
201 ldr r7, [r1], #4
202 orr r3, r3, r7, push #16
203 USER( strt r3, [r0], #4) @ May fault
204 mov ip, r0, lsl #32 - PAGE_SHIFT
205 rsb ip, ip, #0
206 movs ip, ip, lsr #32 - PAGE_SHIFT
207 beq .c2u_2fupi
208 cmp r2, ip
209 movlt ip, r2
210 sub r2, r2, ip
211 subs ip, ip, #16
212 blt .c2u_2rem8lp
213 PLD( pld [r1, #12] )
214 PLD( pld [r0, #12] )
215 PLD( subs ip, ip, #32 )
216 PLD( blt .c2u_2cpynopld )
217 PLD( pld [r1, #28] )
218 PLD( pld [r0, #28] )
220 .c2u_2cpy8lp:
221 PLD( pld [r1, #44] )
222 PLD( pld [r0, #44] )
223 .c2u_2cpynopld: mov r3, r7, pull #16
224 ldmia r1!, {r4 - r7}
225 subs ip, ip, #16
226 orr r3, r3, r4, push #16
227 mov r4, r4, pull #16
228 orr r4, r4, r5, push #16
229 mov r5, r5, pull #16
230 orr r5, r5, r6, push #16
231 mov r6, r6, pull #16
232 orr r6, r6, r7, push #16
233 stmia r0!, {r3 - r6} @ Shouldnt fault
234 bpl .c2u_2cpy8lp
235 PLD( cmn ip, #32 )
236 PLD( bge .c2u_2cpynopld )
237 PLD( add ip, ip, #32 )
239 .c2u_2rem8lp: tst ip, #8
240 movne r3, r7, pull #16
241 ldmneia r1!, {r4, r7}
242 orrne r3, r3, r4, push #16
243 movne r4, r4, pull #16
244 orrne r4, r4, r7, push #16
245 stmneia r0!, {r3 - r4} @ Shouldnt fault
246 tst ip, #4
247 movne r3, r7, pull #16
248 ldrne r7, [r1], #4
249 orrne r3, r3, r7, push #16
250 strnet r3, [r0], #4 @ Shouldnt fault
251 ands ip, ip, #3
252 beq .c2u_2fupi
253 .c2u_2nowords: mov r3, r7, get_byte_2
254 teq ip, #0
255 beq .c2u_finished
256 cmp ip, #2
257 USER( strbt r3, [r0], #1) @ May fault
258 movge r3, r7, get_byte_3
259 USER( strgebt r3, [r0], #1) @ May fault
260 ldrgtb r3, [r1], #0
261 USER( strgtbt r3, [r0], #1) @ May fault
262 b .c2u_finished
264 .c2u_3fupi: subs r2, r2, #4
265 addmi ip, r2, #4
266 bmi .c2u_3nowords
267 mov r3, r7, pull #24
268 ldr r7, [r1], #4
269 orr r3, r3, r7, push #8
270 USER( strt r3, [r0], #4) @ May fault
271 mov ip, r0, lsl #32 - PAGE_SHIFT
272 rsb ip, ip, #0
273 movs ip, ip, lsr #32 - PAGE_SHIFT
274 beq .c2u_3fupi
275 cmp r2, ip
276 movlt ip, r2
277 sub r2, r2, ip
278 subs ip, ip, #16
279 blt .c2u_3rem8lp
280 PLD( pld [r1, #12] )
281 PLD( pld [r0, #12] )
282 PLD( subs ip, ip, #32 )
283 PLD( blt .c2u_3cpynopld )
284 PLD( pld [r1, #28] )
285 PLD( pld [r0, #28] )
287 .c2u_3cpy8lp:
288 PLD( pld [r1, #44] )
289 PLD( pld [r0, #44] )
290 .c2u_3cpynopld: mov r3, r7, pull #24
291 ldmia r1!, {r4 - r7}
292 subs ip, ip, #16
293 orr r3, r3, r4, push #8
294 mov r4, r4, pull #24
295 orr r4, r4, r5, push #8
296 mov r5, r5, pull #24
297 orr r5, r5, r6, push #8
298 mov r6, r6, pull #24
299 orr r6, r6, r7, push #8
300 stmia r0!, {r3 - r6} @ Shouldnt fault
301 bpl .c2u_3cpy8lp
302 PLD( cmn ip, #32 )
303 PLD( bge .c2u_3cpynopld )
304 PLD( add ip, ip, #32 )
306 .c2u_3rem8lp: tst ip, #8
307 movne r3, r7, pull #24
308 ldmneia r1!, {r4, r7}
309 orrne r3, r3, r4, push #8
310 movne r4, r4, pull #24
311 orrne r4, r4, r7, push #8
312 stmneia r0!, {r3 - r4} @ Shouldnt fault
313 tst ip, #4
314 movne r3, r7, pull #24
315 ldrne r7, [r1], #4
316 orrne r3, r3, r7, push #8
317 strnet r3, [r0], #4 @ Shouldnt fault
318 ands ip, ip, #3
319 beq .c2u_3fupi
320 .c2u_3nowords: mov r3, r7, get_byte_3
321 teq ip, #0
322 beq .c2u_finished
323 cmp ip, #2
324 USER( strbt r3, [r0], #1) @ May fault
325 ldrgeb r3, [r1], #1
326 USER( strgebt r3, [r0], #1) @ May fault
327 ldrgtb r3, [r1], #0
328 USER( strgtbt r3, [r0], #1) @ May fault
329 b .c2u_finished
331 .section .fixup,"ax"
332 .align 0
333 9001: LOADREGS(fd,sp!, {r0, r4 - r7, pc})
334 .previous
336 /* Prototype: unsigned long __arch_copy_from_user(void *to,const void *from,unsigned long n);
337 * Purpose : copy a block from user memory to kernel memory
338 * Params : to - kernel memory
339 * : from - user memory
340 * : n - number of bytes to copy
341 * Returns : Number of bytes NOT copied.
342 */
343 .cfu_dest_not_aligned:
344 rsb ip, ip, #4
345 cmp ip, #2
346 USER( ldrbt r3, [r1], #1) @ May fault
347 strb r3, [r0], #1
348 USER( ldrgebt r3, [r1], #1) @ May fault
349 strgeb r3, [r0], #1
350 USER( ldrgtbt r3, [r1], #1) @ May fault
351 strgtb r3, [r0], #1
352 sub r2, r2, ip
353 b .cfu_dest_aligned
355 ENTRY(__arch_copy_from_user)
356 stmfd sp!, {r0, r2, r4 - r7, lr}
357 cmp r2, #4
358 blt .cfu_not_enough
359 PLD( pld [r1, #0] )
360 PLD( pld [r0, #0] )
361 ands ip, r0, #3
362 bne .cfu_dest_not_aligned
363 .cfu_dest_aligned:
364 ands ip, r1, #3
365 bne .cfu_src_not_aligned
366 /*
367 * Seeing as there has to be at least 8 bytes to copy, we can
368 * copy one word, and force a user-mode page fault...
369 */
371 .cfu_0fupi: subs r2, r2, #4
372 addmi ip, r2, #4
373 bmi .cfu_0nowords
374 USER( ldrt r3, [r1], #4)
375 str r3, [r0], #4
376 mov ip, r1, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
377 rsb ip, ip, #0
378 movs ip, ip, lsr #32 - PAGE_SHIFT
379 beq .cfu_0fupi
380 /*
381 * ip = max no. of bytes to copy before needing another "strt" insn
382 */
383 cmp r2, ip
384 movlt ip, r2
385 sub r2, r2, ip
386 subs ip, ip, #32
387 blt .cfu_0rem8lp
388 PLD( pld [r1, #28] )
389 PLD( pld [r0, #28] )
390 PLD( subs ip, ip, #64 )
391 PLD( blt .cfu_0cpynopld )
392 PLD( pld [r1, #60] )
393 PLD( pld [r0, #60] )
395 .cfu_0cpy8lp:
396 PLD( pld [r1, #92] )
397 PLD( pld [r0, #92] )
398 .cfu_0cpynopld: ldmia r1!, {r3 - r6} @ Shouldnt fault
399 stmia r0!, {r3 - r6}
400 ldmia r1!, {r3 - r6} @ Shouldnt fault
401 subs ip, ip, #32
402 stmia r0!, {r3 - r6}
403 bpl .cfu_0cpy8lp
404 PLD( cmn ip, #64 )
405 PLD( bge .cfu_0cpynopld )
406 PLD( add ip, ip, #64 )
408 .cfu_0rem8lp: cmn ip, #16
409 ldmgeia r1!, {r3 - r6} @ Shouldnt fault
410 stmgeia r0!, {r3 - r6}
411 tst ip, #8
412 ldmneia r1!, {r3 - r4} @ Shouldnt fault
413 stmneia r0!, {r3 - r4}
414 tst ip, #4
415 ldrnet r3, [r1], #4 @ Shouldnt fault
416 strne r3, [r0], #4
417 ands ip, ip, #3
418 beq .cfu_0fupi
419 .cfu_0nowords: teq ip, #0
420 beq .cfu_finished
421 .cfu_nowords: cmp ip, #2
422 USER( ldrbt r3, [r1], #1) @ May fault
423 strb r3, [r0], #1
424 USER( ldrgebt r3, [r1], #1) @ May fault
425 strgeb r3, [r0], #1
426 USER( ldrgtbt r3, [r1], #1) @ May fault
427 strgtb r3, [r0], #1
428 b .cfu_finished
430 .cfu_not_enough:
431 movs ip, r2
432 bne .cfu_nowords
433 .cfu_finished: mov r0, #0
434 add sp, sp, #8
435 LOADREGS(fd,sp!,{r4 - r7, pc})
437 .cfu_src_not_aligned:
438 bic r1, r1, #3
439 USER( ldrt r7, [r1], #4) @ May fault
440 cmp ip, #2
441 bgt .cfu_3fupi
442 beq .cfu_2fupi
443 .cfu_1fupi: subs r2, r2, #4
444 addmi ip, r2, #4
445 bmi .cfu_1nowords
446 mov r3, r7, pull #8
447 USER( ldrt r7, [r1], #4) @ May fault
448 orr r3, r3, r7, push #24
449 str r3, [r0], #4
450 mov ip, r1, lsl #32 - PAGE_SHIFT
451 rsb ip, ip, #0
452 movs ip, ip, lsr #32 - PAGE_SHIFT
453 beq .cfu_1fupi
454 cmp r2, ip
455 movlt ip, r2
456 sub r2, r2, ip
457 subs ip, ip, #16
458 blt .cfu_1rem8lp
459 PLD( pld [r1, #12] )
460 PLD( pld [r0, #12] )
461 PLD( subs ip, ip, #32 )
462 PLD( blt .cfu_1cpynopld )
463 PLD( pld [r1, #28] )
464 PLD( pld [r0, #28] )
466 .cfu_1cpy8lp:
467 PLD( pld [r1, #44] )
468 PLD( pld [r0, #44] )
469 .cfu_1cpynopld: mov r3, r7, pull #8
470 ldmia r1!, {r4 - r7} @ Shouldnt fault
471 subs ip, ip, #16
472 orr r3, r3, r4, push #24
473 mov r4, r4, pull #8
474 orr r4, r4, r5, push #24
475 mov r5, r5, pull #8
476 orr r5, r5, r6, push #24
477 mov r6, r6, pull #8
478 orr r6, r6, r7, push #24
479 stmia r0!, {r3 - r6}
480 bpl .cfu_1cpy8lp
481 PLD( cmn ip, #32 )
482 PLD( bge .cfu_1cpynopld )
483 PLD( add ip, ip, #32 )
485 .cfu_1rem8lp: tst ip, #8
486 movne r3, r7, pull #8
487 ldmneia r1!, {r4, r7} @ Shouldnt fault
488 orrne r3, r3, r4, push #24
489 movne r4, r4, pull #8
490 orrne r4, r4, r7, push #24
491 stmneia r0!, {r3 - r4}
492 tst ip, #4
493 movne r3, r7, pull #8
494 USER( ldrnet r7, [r1], #4) @ May fault
495 orrne r3, r3, r7, push #24
496 strne r3, [r0], #4
497 ands ip, ip, #3
498 beq .cfu_1fupi
499 .cfu_1nowords: mov r3, r7, get_byte_1
500 teq ip, #0
501 beq .cfu_finished
502 cmp ip, #2
503 strb r3, [r0], #1
504 movge r3, r7, get_byte_2
505 strgeb r3, [r0], #1
506 movgt r3, r7, get_byte_3
507 strgtb r3, [r0], #1
508 b .cfu_finished
510 .cfu_2fupi: subs r2, r2, #4
511 addmi ip, r2, #4
512 bmi .cfu_2nowords
513 mov r3, r7, pull #16
514 USER( ldrt r7, [r1], #4) @ May fault
515 orr r3, r3, r7, push #16
516 str r3, [r0], #4
517 mov ip, r1, lsl #32 - PAGE_SHIFT
518 rsb ip, ip, #0
519 movs ip, ip, lsr #32 - PAGE_SHIFT
520 beq .cfu_2fupi
521 cmp r2, ip
522 movlt ip, r2
523 sub r2, r2, ip
524 subs ip, ip, #16
525 blt .cfu_2rem8lp
526 PLD( pld [r1, #12] )
527 PLD( pld [r0, #12] )
528 PLD( subs ip, ip, #32 )
529 PLD( blt .cfu_2cpynopld )
530 PLD( pld [r1, #28] )
531 PLD( pld [r0, #28] )
533 .cfu_2cpy8lp:
534 PLD( pld [r1, #44] )
535 PLD( pld [r0, #44] )
536 .cfu_2cpynopld: mov r3, r7, pull #16
537 ldmia r1!, {r4 - r7} @ Shouldnt fault
538 subs ip, ip, #16
539 orr r3, r3, r4, push #16
540 mov r4, r4, pull #16
541 orr r4, r4, r5, push #16
542 mov r5, r5, pull #16
543 orr r5, r5, r6, push #16
544 mov r6, r6, pull #16
545 orr r6, r6, r7, push #16
546 stmia r0!, {r3 - r6}
547 bpl .cfu_2cpy8lp
548 PLD( cmn ip, #32 )
549 PLD( bge .cfu_2cpynopld )
550 PLD( add ip, ip, #32 )
552 .cfu_2rem8lp: tst ip, #8
553 movne r3, r7, pull #16
554 ldmneia r1!, {r4, r7} @ Shouldnt fault
555 orrne r3, r3, r4, push #16
556 movne r4, r4, pull #16
557 orrne r4, r4, r7, push #16
558 stmneia r0!, {r3 - r4}
559 tst ip, #4
560 movne r3, r7, pull #16
561 USER( ldrnet r7, [r1], #4) @ May fault
562 orrne r3, r3, r7, push #16
563 strne r3, [r0], #4
564 ands ip, ip, #3
565 beq .cfu_2fupi
566 .cfu_2nowords: mov r3, r7, get_byte_2
567 teq ip, #0
568 beq .cfu_finished
569 cmp ip, #2
570 strb r3, [r0], #1
571 movge r3, r7, get_byte_3
572 strgeb r3, [r0], #1
573 USER( ldrgtbt r3, [r1], #0) @ May fault
574 strgtb r3, [r0], #1
575 b .cfu_finished
577 .cfu_3fupi: subs r2, r2, #4
578 addmi ip, r2, #4
579 bmi .cfu_3nowords
580 mov r3, r7, pull #24
581 USER( ldrt r7, [r1], #4) @ May fault
582 orr r3, r3, r7, push #8
583 str r3, [r0], #4
584 mov ip, r1, lsl #32 - PAGE_SHIFT
585 rsb ip, ip, #0
586 movs ip, ip, lsr #32 - PAGE_SHIFT
587 beq .cfu_3fupi
588 cmp r2, ip
589 movlt ip, r2
590 sub r2, r2, ip
591 subs ip, ip, #16
592 blt .cfu_3rem8lp
593 PLD( pld [r1, #12] )
594 PLD( pld [r0, #12] )
595 PLD( subs ip, ip, #32 )
596 PLD( blt .cfu_3cpynopld )
597 PLD( pld [r1, #28] )
598 PLD( pld [r0, #28] )
600 .cfu_3cpy8lp:
601 PLD( pld [r1, #44] )
602 PLD( pld [r0, #44] )
603 .cfu_3cpynopld: mov r3, r7, pull #24
604 ldmia r1!, {r4 - r7} @ Shouldnt fault
605 orr r3, r3, r4, push #8
606 mov r4, r4, pull #24
607 orr r4, r4, r5, push #8
608 mov r5, r5, pull #24
609 orr r5, r5, r6, push #8
610 mov r6, r6, pull #24
611 orr r6, r6, r7, push #8
612 stmia r0!, {r3 - r6}
613 subs ip, ip, #16
614 bpl .cfu_3cpy8lp
615 PLD( cmn ip, #32 )
616 PLD( bge .cfu_3cpynopld )
617 PLD( add ip, ip, #32 )
619 .cfu_3rem8lp: tst ip, #8
620 movne r3, r7, pull #24
621 ldmneia r1!, {r4, r7} @ Shouldnt fault
622 orrne r3, r3, r4, push #8
623 movne r4, r4, pull #24
624 orrne r4, r4, r7, push #8
625 stmneia r0!, {r3 - r4}
626 tst ip, #4
627 movne r3, r7, pull #24
628 USER( ldrnet r7, [r1], #4) @ May fault
629 orrne r3, r3, r7, push #8
630 strne r3, [r0], #4
631 ands ip, ip, #3
632 beq .cfu_3fupi
633 .cfu_3nowords: mov r3, r7, get_byte_3
634 teq ip, #0
635 beq .cfu_finished
636 cmp ip, #2
637 strb r3, [r0], #1
638 USER( ldrgebt r3, [r1], #1) @ May fault
639 strgeb r3, [r0], #1
640 USER( ldrgtbt r3, [r1], #1) @ May fault
641 strgtb r3, [r0], #1
642 b .cfu_finished
644 .section .fixup,"ax"
645 .align 0
646 /*
647 * We took an exception. r0 contains a pointer to
648 * the byte not copied.
649 */
650 9001: ldr r2, [sp], #4 @ void *to
651 sub r2, r0, r2 @ bytes copied
652 ldr r1, [sp], #4 @ unsigned long count
653 subs r4, r1, r2 @ bytes left to copy
654 movne r1, r4
655 blne __memzero
656 mov r0, r4
657 LOADREGS(fd,sp!, {r4 - r7, pc})
658 .previous
660 /* Prototype: int __arch_clear_user(void *addr, size_t sz)
661 * Purpose : clear some user memory
662 * Params : addr - user memory address to clear
663 * : sz - number of bytes to clear
664 * Returns : number of bytes NOT cleared
665 */
666 ENTRY(__arch_clear_user)
667 stmfd sp!, {r1, lr}
668 mov r2, #0
669 cmp r1, #4
670 blt 2f
671 ands ip, r0, #3
672 beq 1f
673 cmp ip, #2
674 USER( strbt r2, [r0], #1)
675 USER( strlebt r2, [r0], #1)
676 USER( strltbt r2, [r0], #1)
677 rsb ip, ip, #4
678 sub r1, r1, ip @ 7 6 5 4 3 2 1
679 1: subs r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7
680 USER( strplt r2, [r0], #4)
681 USER( strplt r2, [r0], #4)
682 bpl 1b
683 adds r1, r1, #4 @ 3 2 1 0 -1 -2 -3
684 USER( strplt r2, [r0], #4)
685 2: tst r1, #2 @ 1x 1x 0x 0x 1x 1x 0x
686 USER( strnebt r2, [r0], #1)
687 USER( strnebt r2, [r0], #1)
688 tst r1, #1 @ x1 x0 x1 x0 x1 x0 x1
689 USER( strnebt r2, [r0], #1)
690 mov r0, #0
691 LOADREGS(fd,sp!, {r1, pc})
693 .section .fixup,"ax"
694 .align 0
695 9001: LOADREGS(fd,sp!, {r0, pc})
696 .previous