aboutsummaryrefslogblamecommitdiffstats
path: root/arch/sparc/lib/copy_user.S
blob: 577505b692ae0643b046223187d071de9106f618 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492











































































































































































































































































































































































































































































































                                                                              
/* copy_user.S: Sparc optimized copy_from_user and copy_to_user code.
 *
 *  Copyright(C) 1995 Linus Torvalds
 *  Copyright(C) 1996 David S. Miller
 *  Copyright(C) 1996 Eddie C. Dost
 *  Copyright(C) 1996,1998 Jakub Jelinek
 *
 * derived from:
 *	e-mail between David and Eddie.
 *
 * Returns 0 if successful, otherwise count of bytes not copied yet
 */

#include <asm/ptrace.h>
#include <asm/asmmacro.h>
#include <asm/page.h>

/* Work around cpp -rob */
#define ALLOC #alloc
#define EXECINSTR #execinstr
#define EX(x,y,a,b) 				\
98: 	x,y;					\
	.section .fixup,ALLOC,EXECINSTR;	\
	.align	4;				\
99:	ba fixupretl;				\
	 a, b, %g3;				\
	.section __ex_table,ALLOC;		\
	.align	4;				\
	.word	98b, 99b;			\
	.text;					\
	.align	4

#define EX2(x,y,c,d,e,a,b) 			\
98: 	x,y;					\
	.section .fixup,ALLOC,EXECINSTR;	\
	.align	4;				\
99:	c, d, e;				\
	ba fixupretl;				\
	 a, b, %g3;				\
	.section __ex_table,ALLOC;		\
	.align	4;				\
	.word	98b, 99b;			\
	.text;					\
	.align	4

#define EXO2(x,y) 				\
98: 	x, y;					\
	.section __ex_table,ALLOC;		\
	.align	4;				\
	.word	98b, 97f;			\
	.text;					\
	.align	4

#define EXT(start,end,handler)			\
	.section __ex_table,ALLOC;		\
	.align	4;				\
	.word	start, 0, end, handler;		\
	.text;					\
	.align	4

/* Please do not change following macros unless you change logic used
 * in .fixup at the end of this file as well
 */

/* Both these macros have to start with exactly the same insn */
#define MOVE_BIGCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \
	ldd	[%src + (offset) + 0x00], %t0; \
	ldd	[%src + (offset) + 0x08], %t2; \
	ldd	[%src + (offset) + 0x10], %t4; \
	ldd	[%src + (offset) + 0x18], %t6; \
	st	%t0, [%dst + (offset) + 0x00]; \
	st	%t1, [%dst + (offset) + 0x04]; \
	st	%t2, [%dst + (offset) + 0x08]; \
	st	%t3, [%dst + (offset) + 0x0c]; \
	st	%t4, [%dst + (offset) + 0x10]; \
	st	%t5, [%dst + (offset) + 0x14]; \
	st	%t6, [%dst + (offset) + 0x18]; \
	st	%t7, [%dst + (offset) + 0x1c];

#define MOVE_BIGALIGNCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \
	ldd	[%src + (offset) + 0x00], %t0; \
	ldd	[%src + (offset) + 0x08], %t2; \
	ldd	[%src + (offset) + 0x10], %t4; \
	ldd	[%src + (offset) + 0x18], %t6; \
	std	%t0, [%dst + (offset) + 0x00]; \
	std	%t2, [%dst + (offset) + 0x08]; \
	std	%t4, [%dst + (offset) + 0x10]; \
	std	%t6, [%dst + (offset) + 0x18];

#define MOVE_LASTCHUNK(src, dst, offset, t0, t1, t2, t3) \
	ldd	[%src - (offset) - 0x10], %t0; \
	ldd	[%src - (offset) - 0x08], %t2; \
	st	%t0, [%dst - (offset) - 0x10]; \
	st	%t1, [%dst - (offset) - 0x0c]; \
	st	%t2, [%dst - (offset) - 0x08]; \
	st	%t3, [%dst - (offset) - 0x04];

#define MOVE_HALFCHUNK(src, dst, offset, t0, t1, t2, t3) \
	lduh	[%src + (offset) + 0x00], %t0; \
	lduh	[%src + (offset) + 0x02], %t1; \
	lduh	[%src + (offset) + 0x04], %t2; \
	lduh	[%src + (offset) + 0x06], %t3; \
	sth	%t0, [%dst + (offset) + 0x00]; \
	sth	%t1, [%dst + (offset) + 0x02]; \
	sth	%t2, [%dst + (offset) + 0x04]; \
	sth	%t3, [%dst + (offset) + 0x06];

#define MOVE_SHORTCHUNK(src, dst, offset, t0, t1) \
	ldub	[%src - (offset) - 0x02], %t0; \
	ldub	[%src - (offset) - 0x01], %t1; \
	stb	%t0, [%dst - (offset) - 0x02]; \
	stb	%t1, [%dst - (offset) - 0x01];

	.text
	.align	4

	.globl  __copy_user_begin
__copy_user_begin:

	.globl	__copy_user
dword_align:
	andcc	%o1, 1, %g0
	be	4f
	 andcc	%o1, 2, %g0

	EXO2(ldub [%o1], %g2)
	add	%o1, 1, %o1
	EXO2(stb %g2, [%o0])
	sub	%o2, 1, %o2
	bne	3f
	 add	%o0, 1, %o0

	EXO2(lduh [%o1], %g2)
	add	%o1, 2, %o1
	EXO2(sth %g2, [%o0])
	sub	%o2, 2, %o2
	b	3f
	 add	%o0, 2, %o0
4:
	EXO2(lduh [%o1], %g2)
	add	%o1, 2, %o1
	EXO2(sth %g2, [%o0])
	sub	%o2, 2, %o2
	b	3f
	 add	%o0, 2, %o0

__copy_user:	/* %o0=dst %o1=src %o2=len */
	xor	%o0, %o1, %o4
1:
	andcc	%o4, 3, %o5
2:
	bne	cannot_optimize
	 cmp	%o2, 15

	bleu	short_aligned_end
	 andcc	%o1, 3, %g0

	bne	dword_align
3:
	 andcc	%o1, 4, %g0

	be	2f
	 mov	%o2, %g1

	EXO2(ld [%o1], %o4)
	sub	%g1, 4, %g1
	EXO2(st %o4, [%o0])
	add	%o1, 4, %o1
	add	%o0, 4, %o0
2:
	andcc	%g1, 0xffffff80, %g7
	be	3f
	 andcc	%o0, 4, %g0

	be	ldd_std + 4
5:
	MOVE_BIGCHUNK(o1, o0, 0x00, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5)
80:
	EXT(5b, 80b, 50f)
	subcc	%g7, 128, %g7
	add	%o1, 128, %o1
	bne	5b
	 add	%o0, 128, %o0
3:
	andcc	%g1, 0x70, %g7
	be	copy_user_table_end
	 andcc	%g1, 8, %g0

	sethi	%hi(copy_user_table_end), %o5
	srl	%g7, 1, %o4
	add	%g7, %o4, %o4
	add	%o1, %g7, %o1
	sub	%o5, %o4, %o5
	jmpl	%o5 + %lo(copy_user_table_end), %g0
	 add	%o0, %g7, %o0

copy_user_table:
	MOVE_LASTCHUNK(o1, o0, 0x60, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x50, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x40, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x30, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x20, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x10, g2, g3, g4, g5)
	MOVE_LASTCHUNK(o1, o0, 0x00, g2, g3, g4, g5)
copy_user_table_end:
	EXT(copy_user_table, copy_user_table_end, 51f)
	be	copy_user_last7
	 andcc	%g1, 4, %g0

	EX(ldd	[%o1], %g2, and %g1, 0xf)
	add	%o0, 8, %o0
	add	%o1, 8, %o1
	EX(st	%g2, [%o0 - 0x08], and %g1, 0xf)
	EX2(st	%g3, [%o0 - 0x04], and %g1, 0xf, %g1, sub %g1, 4)
copy_user_last7:
	be	1f
	 andcc	%g1, 2, %g0

	EX(ld	[%o1], %g2, and %g1, 7)
	add	%o1, 4, %o1
	EX(st	%g2, [%o0], and %g1, 7)
	add	%o0, 4, %o0
1:
	be	1f
	 andcc	%g1, 1, %g0

	EX(lduh	[%o1], %g2, and %g1, 3)
	add	%o1, 2, %o1
	EX(sth	%g2, [%o0], and %g1, 3)
	add	%o0, 2, %o0
1:
	be	1f
	 nop

	EX(ldub	[%o1], %g2, add %g0, 1)
	EX(stb	%g2, [%o0], add %g0, 1)
1:
	retl
 	 clr	%o0

ldd_std:
	MOVE_BIGALIGNCHUNK(o1, o0, 0x00, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGALIGNCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGALIGNCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5)
	MOVE_BIGALIGNCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5)
81:
	EXT(ldd_std, 81b, 52f)
	subcc	%g7, 128, %g7
	add	%o1, 128, %o1
	bne	ldd_std
	 add	%o0, 128, %o0

	andcc	%g1, 0x70, %g7
	be	copy_user_table_end
	 andcc	%g1, 8, %g0

	sethi	%hi(copy_user_table_end), %o5
	srl	%g7, 1, %o4
	add	%g7, %o4, %o4
	add	%o1, %g7, %o1
	sub	%o5, %o4, %o5
	jmpl	%o5 + %lo(copy_user_table_end), %g0
	 add	%o0, %g7, %o0

cannot_optimize:
	bleu	short_end
	 cmp	%o5, 2

	bne	byte_chunk
	 and	%o2, 0xfffffff0, %o3
	 
	andcc	%o1, 1, %g0
	be	10f
	 nop

	EXO2(ldub [%o1], %g2)
	add	%o1, 1, %o1
	EXO2(stb %g2, [%o0])
	sub	%o2, 1, %o2
	andcc	%o2, 0xfffffff0, %o3
	be	short_end
	 add	%o0, 1, %o0
10:
	MOVE_HALFCHUNK(o1, o0, 0x00, g2, g3, g4, g5)
	MOVE_HALFCHUNK(o1, o0, 0x08, g2, g3, g4, g5)
82:
	EXT(10b, 82b, 53f)
	subcc	%o3, 0x10, %o3
	add	%o1, 0x10, %o1
	bne	10b
	 add	%o0, 0x10, %o0
	b	2f
	 and	%o2, 0xe, %o3
	
byte_chunk:
	MOVE_SHORTCHUNK(o1, o0, -0x02, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x04, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x06, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x08, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x0a, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x0c, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x0e, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, -0x10, g2, g3)
83:
	EXT(byte_chunk, 83b, 54f)
	subcc	%o3, 0x10, %o3
	add	%o1, 0x10, %o1
	bne	byte_chunk
	 add	%o0, 0x10, %o0

short_end:
	and	%o2, 0xe, %o3
2:
	sethi	%hi(short_table_end), %o5
	sll	%o3, 3, %o4
	add	%o0, %o3, %o0
	sub	%o5, %o4, %o5
	add	%o1, %o3, %o1
	jmpl	%o5 + %lo(short_table_end), %g0
	 andcc	%o2, 1, %g0
84:
	MOVE_SHORTCHUNK(o1, o0, 0x0c, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x0a, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x08, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x06, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x04, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x02, g2, g3)
	MOVE_SHORTCHUNK(o1, o0, 0x00, g2, g3)
short_table_end:
	EXT(84b, short_table_end, 55f)
	be	1f
	 nop
	EX(ldub	[%o1], %g2, add %g0, 1)
	EX(stb	%g2, [%o0], add %g0, 1)
1:
	retl
 	 clr	%o0

short_aligned_end:
	bne	short_end
	 andcc	%o2, 8, %g0

	be	1f
	 andcc	%o2, 4, %g0

	EXO2(ld	[%o1 + 0x00], %g2)
	EXO2(ld	[%o1 + 0x04], %g3)
	add	%o1, 8, %o1
	EXO2(st	%g2, [%o0 + 0x00])
	EX(st	%g3, [%o0 + 0x04], sub %o2, 4)
	add	%o0, 8, %o0
1:
	b	copy_user_last7
	 mov	%o2, %g1

	.section .fixup,#alloc,#execinstr
	.align	4
97:
	mov	%o2, %g3
fixupretl:
	sethi   %hi(PAGE_OFFSET), %g1
	cmp	%o0, %g1
	blu	1f
	 cmp	%o1, %g1
	bgeu	1f
	 nop
	save	%sp, -64, %sp
	mov	%i0, %o0
	call	__bzero
	 mov	%g3, %o1
	restore
1:	retl
	 mov	%g3, %o0

/* exception routine sets %g2 to (broken_insn - first_insn)>>2 */
50:
/* This magic counts how many bytes are left when crash in MOVE_BIGCHUNK
 * happens. This is derived from the amount ldd reads, st stores, etc.
 * x = g2 % 12;
 * g3 = g1 + g7 - ((g2 / 12) * 32 + (x < 4) ? 0 : (x - 4) * 4);
 * o0 += (g2 / 12) * 32;
 */
	cmp	%g2, 12
	add	%o0, %g7, %o0
	bcs	1f
	 cmp	%g2, 24
	bcs	2f
	 cmp	%g2, 36
	bcs	3f
	 nop
	sub	%g2, 12, %g2
	sub	%g7, 32, %g7
3:	sub	%g2, 12, %g2
	sub	%g7, 32, %g7
2:	sub	%g2, 12, %g2
	sub	%g7, 32, %g7
1:	cmp	%g2, 4
	bcs,a	60f
	 clr	%g2
	sub	%g2, 4, %g2
	sll	%g2, 2, %g2
60:	and	%g1, 0x7f, %g3
	sub	%o0, %g7, %o0
	add	%g3, %g7, %g3
	ba	fixupretl
	 sub	%g3, %g2, %g3
51:
/* i = 41 - g2; j = i % 6;
 * g3 = (g1 & 15) + (i / 6) * 16 + (j < 4) ? (j + 1) * 4 : 16;
 * o0 -= (i / 6) * 16 + 16;
 */
	neg	%g2
	and	%g1, 0xf, %g1
	add	%g2, 41, %g2
	add	%o0, %g1, %o0
1:	cmp	%g2, 6
	bcs,a	2f
	 cmp	%g2, 4
	add	%g1, 16, %g1
	b	1b
	 sub	%g2, 6, %g2
2:	bcc,a	2f
	 mov	16, %g2
	inc	%g2
	sll	%g2, 2, %g2
2:	add	%g1, %g2, %g3
	ba	fixupretl
	 sub	%o0, %g3, %o0
52:
/* g3 = g1 + g7 - (g2 / 8) * 32 + (g2 & 4) ? (g2 & 3) * 8 : 0;
   o0 += (g2 / 8) * 32 */
	andn	%g2, 7, %g4
	add	%o0, %g7, %o0
	andcc	%g2, 4, %g0
	and	%g2, 3, %g2
	sll	%g4, 2, %g4
	sll	%g2, 3, %g2
	bne	60b
	 sub	%g7, %g4, %g7
	ba	60b
	 clr	%g2
53:
/* g3 = o3 + (o2 & 15) - (g2 & 8) - (g2 & 4) ? (g2 & 3) * 2 : 0;
   o0 += (g2 & 8) */
	and	%g2, 3, %g4
	andcc	%g2, 4, %g0
	and	%g2, 8, %g2
	sll	%g4, 1, %g4
	be	1f
	 add	%o0, %g2, %o0
	add	%g2, %g4, %g2
1:	and	%o2, 0xf, %g3
	add	%g3, %o3, %g3
	ba	fixupretl
	 sub	%g3, %g2, %g3
54:
/* g3 = o3 + (o2 & 15) - (g2 / 4) * 2 - (g2 & 2) ? (g2 & 1) : 0;
   o0 += (g2 / 4) * 2 */
	srl	%g2, 2, %o4
	and	%g2, 1, %o5
	srl	%g2, 1, %g2
	add	%o4, %o4, %o4
	and	%o5, %g2, %o5
	and	%o2, 0xf, %o2
	add	%o0, %o4, %o0
	sub	%o3, %o5, %o3
	sub	%o2, %o4, %o2
	ba	fixupretl
	 add	%o2, %o3, %g3
55:
/* i = 27 - g2;
   g3 = (o2 & 1) + i / 4 * 2 + !(i & 3);
   o0 -= i / 4 * 2 + 1 */
	neg	%g2
	and	%o2, 1, %o2
	add	%g2, 27, %g2
	srl	%g2, 2, %o5
	andcc	%g2, 3, %g0
	mov	1, %g2
	add	%o5, %o5, %o5
	be,a	1f
	 clr	%g2
1:	add	%g2, %o5, %g3
	sub	%o0, %g3, %o0
	ba	fixupretl
	 add	%g3, %o2, %g3

	.globl  __copy_user_end
__copy_user_end: