summaryrefslogtreecommitdiffstats
path: root/arch/sh/kernel/process_64.c
blob: cff3b7dc9c563e2fec79cf64aec1143d161101da (plain)
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
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
/*
 * arch/sh/kernel/process_64.c
 *
 * This file handles the architecture-dependent parts of process handling..
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003 - 2007  Paul Mundt
 * Copyright (C) 2003, 2004 Richard Curnow
 *
 * Started from SH3/4 version:
 *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *
 *   In turn started from i386 version:
 *     Copyright (C) 1995  Linus Torvalds
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/io.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>

struct task_struct *last_task_used_math = NULL;

static int hlt_counter = 1;

#define HARD_IDLE_TIMEOUT (HZ / 3)

void disable_hlt(void)
{
	hlt_counter++;
}

void enable_hlt(void)
{
	hlt_counter--;
}

static int __init nohlt_setup(char *__unused)
{
	hlt_counter = 1;
	return 1;
}

static int __init hlt_setup(char *__unused)
{
	hlt_counter = 0;
	return 1;
}

__setup("nohlt", nohlt_setup);
__setup("hlt", hlt_setup);

static inline void hlt(void)
{
	__asm__ __volatile__ ("sleep" : : : "memory");
}

/*
 * The idle loop on a uniprocessor SH..
 */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		if (hlt_counter) {
			while (!need_resched())
				cpu_relax();
		} else {
			local_irq_disable();
			while (!need_resched()) {
				local_irq_enable();
				hlt();
				local_irq_disable();
			}
			local_irq_enable();
		}
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}

}

void machine_restart(char * __unused)
{
	extern void phys_stext(void);

	phys_stext();
}

void machine_halt(void)
{
	for (;;);
}

void machine_power_off(void)
{
#if 0
	/* Disable watchdog timer */
	ctrl_outl(0xa5000000, WTCSR);
	/* Configure deep standby on sleep */
	ctrl_outl(0x03, STBCR);
#endif

	__asm__ __volatile__ (
		"sleep\n\t"
		"synci\n\t"
		"nop;nop;nop;nop\n\t"
	);

	panic("Unexpected wakeup!\n");
}

void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);

void show_regs(struct pt_regs * regs)
{
	unsigned long long ah, al, bh, bl, ch, cl;

	printk("\n");

	ah = (regs->pc) >> 32;
	al = (regs->pc) & 0xffffffff;
	bh = (regs->regs[18]) >> 32;
	bl = (regs->regs[18]) & 0xffffffff;
	ch = (regs->regs[15]) >> 32;
	cl = (regs->regs[15]) & 0xffffffff;
	printk("PC  : %08Lx%08Lx LINK: %08Lx%08Lx SP  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->sr) >> 32;
	al = (regs->sr) & 0xffffffff;
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bh));
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bl));
	bh = (bh) >> 32;
	bl = (bl) & 0xffffffff;
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (ch));
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (cl));
	ch = (ch) >> 32;
	cl = (cl) & 0xffffffff;
	printk("SR  : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[0]) >> 32;
	al = (regs->regs[0]) & 0xffffffff;
	bh = (regs->regs[1]) >> 32;
	bl = (regs->regs[1]) & 0xffffffff;
	ch = (regs->regs[2]) >> 32;
	cl = (regs->regs[2]) & 0xffffffff;
	printk("R0  : %08Lx%08Lx R1  : %08Lx%08Lx R2  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[3]) >> 32;
	al = (regs->regs[3]) & 0xffffffff;
	bh = (regs->regs[4]) >> 32;
	bl = (regs->regs[4]) & 0xffffffff;
	ch = (regs->regs[5]) >> 32;
	cl = (regs->regs[5]) & 0xffffffff;
	printk("R3  : %08Lx%08Lx R4  : %08Lx%08Lx R5  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[6]) >> 32;
	al = (regs->regs[6]) & 0xffffffff;
	bh = (regs->regs[7]) >> 32;
	bl = (regs->regs[7]) & 0xffffffff;
	ch = (regs->regs[8]) >> 32;
	cl = (regs->regs[8]) & 0xffffffff;
	printk("R6  : %08Lx%08Lx R7  : %08Lx%08Lx R8  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[9]) >> 32;
	al = (regs->regs[9]) & 0xffffffff;
	bh = (regs->regs[10]) >> 32;
	bl = (regs->regs[10]) & 0xffffffff;
	ch = (regs->regs[11]) >> 32;
	cl = (regs->regs[11]) & 0xffffffff;
	printk("R9  : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[12]) >> 32;
	al = (regs->regs[12]) & 0xffffffff;
	bh = (regs->regs[13]) >> 32;
	bl = (regs->regs[13]) & 0xffffffff;
	ch = (regs->regs[14]) >> 32;
	cl = (regs->regs[14]) & 0xffffffff;
	printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[16]) >> 32;
	al = (regs->regs[16]) & 0xffffffff;
	bh = (regs->regs[17]) >> 32;
	bl = (regs->regs[17]) & 0xffffffff;
	ch = (regs->regs[19]) >> 32;
	cl = (regs->regs[19]) & 0xffffffff;
	printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[20]) >> 32;
	al = (regs->regs[20]) & 0xffffffff;
	bh = (regs->regs[21]) >> 32;
	bl = (regs->regs[21]) & 0xffffffff;
	ch = (regs->regs[22]) >> 32;
	cl = (regs->regs[22]) & 0xffffffff;
	printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[23]) >> 32;
	al = (regs->regs[23]) & 0xffffffff;
	bh = (regs->regs[24]) >> 32;
	bl = (regs->regs[24]) & 0xffffffff;
	ch = (regs->regs[25]) >> 32;
	cl = (regs->regs[25]) & 0xffffffff;
	printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[26]) >> 32;
	al = (regs->regs[26]) & 0xffffffff;
	bh = (regs->regs[27]) >> 32;
	bl = (regs->regs[27]) & 0xffffffff;
	ch = (regs->regs[28]) >> 32;
	cl = (regs->regs[28]) & 0xffffffff;
	printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[29]) >> 32;
	al = (regs->regs[29]) & 0xffffffff;
	bh = (regs->regs[30]) >> 32;
	bl = (regs->regs[30]) & 0xffffffff;
	ch = (regs->regs[31]) >> 32;
	cl = (regs->regs[31]) & 0xffffffff;
	printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[32]) >> 32;
	al = (regs->regs[32]) & 0xffffffff;
	bh = (regs->regs[33]) >> 32;
	bl = (regs->regs[33]) & 0xffffffff;
	ch = (regs->regs[34]) >> 32;
	cl = (regs->regs[34]) & 0xffffffff;
	printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[35]) >> 32;
	al = (regs->regs[35]) & 0xffffffff;
	bh = (regs->regs[36]) >> 32;
	bl = (regs->regs[36]) & 0xffffffff;
	ch = (regs->regs[37]) >> 32;
	cl = (regs->regs[37]) & 0xffffffff;
	printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[38]) >> 32;
	al = (regs->regs[38]) & 0xffffffff;
	bh = (regs->regs[39]) >> 32;
	bl = (regs->regs[39]) & 0xffffffff;
	ch = (regs->regs[40]) >> 32;
	cl = (regs->regs[40]) & 0xffffffff;
	printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[41]) >> 32;
	al = (regs->regs[41]) & 0xffffffff;
	bh = (regs->regs[42]) >> 32;
	bl = (regs->regs[42]) & 0xffffffff;
	ch = (regs->regs[43]) >> 32;
	cl = (regs->regs[43]) & 0xffffffff;
	printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[44]) >> 32;
	al = (regs->regs[44]) & 0xffffffff;
	bh = (regs->regs[45]) >> 32;
	bl = (regs->regs[45]) & 0xffffffff;
	ch = (regs->regs[46]) >> 32;
	cl = (regs->regs[46]) & 0xffffffff;
	printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[47]) >> 32;
	al = (regs->regs[47]) & 0xffffffff;
	bh = (regs->regs[48]) >> 32;
	bl = (regs->regs[48]) & 0xffffffff;
	ch = (regs->regs[49]) >> 32;
	cl = (regs->regs[49]) & 0xffffffff;
	printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[50]) >> 32;
	al = (regs->regs[50]) & 0xffffffff;
	bh = (regs->regs[51]) >> 32;
	bl = (regs->regs[51]) & 0xffffffff;
	ch = (regs->regs[52]) >> 32;
	cl = (regs->regs[52]) & 0xffffffff;
	printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[53]) >> 32;
	al = (regs->regs[53]) & 0xffffffff;
	bh = (regs->regs[54]) >> 32;
	bl = (regs->regs[54]) & 0xffffffff;
	ch = (regs->regs[55]) >> 32;
	cl = (regs->regs[55]) & 0xffffffff;
	printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[56]) >> 32;
	al = (regs->regs[56]) & 0xffffffff;
	bh = (regs->regs[57]) >> 32;
	bl = (regs->regs[57]) & 0xffffffff;
	ch = (regs->regs[58]) >> 32;
	cl = (regs->regs[58]) & 0xffffffff;
	printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[59]) >> 32;
	al = (regs->regs[59]) & 0xffffffff;
	bh = (regs->regs[60]) >> 32;
	bl = (regs->regs[60]) & 0xffffffff;
	ch = (regs->regs[61]) >> 32;
	cl = (regs->regs[61]) & 0xffffffff;
	printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[62]) >> 32;
	al = (regs->regs[62]) & 0xffffffff;
	bh = (regs->tregs[0]) >> 32;
	bl = (regs->tregs[0]) & 0xffffffff;
	ch = (regs->tregs[1]) >> 32;
	cl = (regs->tregs[1]) & 0xffffffff;
	printk("R62 : %08Lx%08Lx T0  : %08Lx%08Lx T1  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[2]) >> 32;
	al = (regs->tregs[2]) & 0xffffffff;
	bh = (regs->tregs[3]) >> 32;
	bl = (regs->tregs[3]) & 0xffffffff;
	ch = (regs->tregs[4]) >> 32;
	cl = (regs->tregs[4]) & 0xffffffff;
	printk("T2  : %08Lx%08Lx T3  : %08Lx%08Lx T4  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[5]) >> 32;
	al = (regs->tregs[5]) & 0xffffffff;
	bh = (regs->tregs[6]) >> 32;
	bl = (regs->tregs[6]) & 0xffffffff;
	ch = (regs->tregs[7]) >> 32;
	cl = (regs->tregs[7]) & 0xffffffff;
	printk("T5  : %08Lx%08Lx T6  : %08Lx%08Lx T7  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	/*
	 * If we're in kernel mode, dump the stack too..
	 */
	if (!user_mode(regs)) {
		void show_stack(struct task_struct *tsk, unsigned long *sp);
		unsigned long sp = regs->regs[15] & 0xffffffff;
		struct task_struct *tsk = get_current();

		tsk->thread.kregs = regs;

		show_stack(tsk, (unsigned long *)sp);
	}
}

struct task_struct * alloc_task_struct(void)
{
	/* Get task descriptor pages */
	return (struct task_struct *)
		__get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
}

void free_task_struct(struct task_struct *p)
{
	free_pages((unsigned long) p, get_order(THREAD_SIZE));
}

/*
 * Create a kernel thread
 */
ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
{
	do_exit(fn(arg));
}

/*
 * This is the mechanism for creating a new kernel thread.
 *
 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 * who haven't done an "execve()") should use this: it will work within
 * a system call from a "real" process, but the process memory space will
 * not be freed until both the parent and the child have exited.
 */
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
	struct pt_regs regs;

	memset(&regs, 0, sizeof(regs));
	regs.regs[2] = (unsigned long)arg;
	regs.regs[3] = (unsigned long)fn;

	regs.pc = (unsigned long)kernel_thread_helper;
	regs.sr = (1 << 30);

	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
		       &regs, 0, NULL, NULL);
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
	/*
	 * See arch/sparc/kernel/process.c for the precedent for doing
	 * this -- RPC.
	 *
	 * The SH-5 FPU save/restore approach relies on
	 * last_task_used_math pointing to a live task_struct.  When
	 * another task tries to use the FPU for the 1st time, the FPUDIS
	 * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
	 * existing FPU state to the FP regs field within
	 * last_task_used_math before re-loading the new task's FPU state
	 * (or initialising it if the FPU has been used before).  So if
	 * last_task_used_math is stale, and its page has already been
	 * re-allocated for another use, the consequences are rather
	 * grim. Unless we null it here, there is no other path through
	 * which it would get safely nulled.
	 */
#ifdef CONFIG_SH_FPU
	if (last_task_used_math == current) {
		last_task_used_math = NULL;
	}
#endif
}

void flush_thread(void)
{

	/* Called by fs/exec.c (flush_old_exec) to remove traces of a
	 * previously running executable. */
#ifdef CONFIG_SH_FPU
	if (last_task_used_math == current) {
		last_task_used_math = NULL;
	}
	/* Force FPU state to be reinitialised after exec */
	clear_used_math();
#endif

	/* if we are a kernel thread, about to change to user thread,
         * update kreg
         */
	if(current->thread.kregs==&fake_swapper_regs) {
          current->thread.kregs =
             ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
	  current->thread.uregs = current->thread.kregs;
	}
}

void release_thread(struct task_struct *dead_task)
{
	/* do nothing */
}

/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
#ifdef CONFIG_SH_FPU
	int fpvalid;
	struct task_struct *tsk = current;

	fpvalid = !!tsk_used_math(tsk);
	if (fpvalid) {
		if (current == last_task_used_math) {
			enable_fpu();
			save_fpu(tsk, regs);
			disable_fpu();
			last_task_used_math = 0;
			regs->sr |= SR_FD;
		}

		memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	}

	return fpvalid;
#else
	return 0; /* Task didn't use the fpu at all. */
#endif
}

asmlinkage void ret_from_fork(void);

int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
		unsigned long unused,
		struct task_struct *p, struct pt_regs *regs)
{
	struct pt_regs *childregs;
	unsigned long long se;			/* Sign extension */

#ifdef CONFIG_SH_FPU
	if(last_task_used_math == current) {
		enable_fpu();
		save_fpu(current, regs);
		disable_fpu();
		last_task_used_math = NULL;
		regs->sr |= SR_FD;
	}
#endif
	/* Copy from sh version */
	childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;

	*childregs = *regs;

	if (user_mode(regs)) {
		childregs->regs[15] = usp;
		p->thread.uregs = childregs;
	} else {
		childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
	}

	childregs->regs[9] = 0; /* Set return value for child */
	childregs->sr |= SR_FD; /* Invalidate FPU flag */

	p->thread.sp = (unsigned long) childregs;
	p->thread.pc = (unsigned long) ret_from_fork;

	/*
	 * Sign extend the edited stack.
         * Note that thread.pc and thread.pc will stay
	 * 32-bit wide and context switch must take care
	 * of NEFF sign extension.
	 */

	se = childregs->regs[15];
	se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
	childregs->regs[15] = se;

	return 0;
}

asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
			unsigned long r4, unsigned long r5,
			unsigned long r6, unsigned long r7,
			struct pt_regs *pregs)
{
	return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
}

asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
			 unsigned long r4, unsigned long r5,
			 unsigned long r6, unsigned long r7,
			 struct pt_regs *pregs)
{
	if (!newsp)
		newsp = pregs->regs[15];
	return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
}

/*
 * This is trivial, and on the face of it looks like it
 * could equally well be done in user mode.
 *
 * Not so, for quite unobvious reasons - register pressure.
 * In user mode vfork() cannot have a stack frame, and if
 * done by calling the "clone()" system call directly, you
 * do not have enough call-clobbered registers to hold all
 * the information you need.
 */
asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
			 unsigned long r4, unsigned long r5,
			 unsigned long r6, unsigned long r7,
			 struct pt_regs *pregs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
}

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys_execve(char *ufilename, char **uargv,
			  char **uenvp, unsigned long r5,
			  unsigned long r6, unsigned long r7,
			  struct pt_regs *pregs)
{
	int error;
	char *filename;

	lock_kernel();
	filename = getname((char __user *)ufilename);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;

	error = do_execve(filename,
			  (char __user * __user *)uargv,
			  (char __user * __user *)uenvp,
			  pregs);
	if (error == 0) {
		task_lock(current);
		current->ptrace &= ~PT_DTRACE;
		task_unlock(current);
	}
	putname(filename);
out:
	unlock_kernel();
	return error;
}

/*
 * These bracket the sleeping functions..
 */
extern void interruptible_sleep_on(wait_queue_head_t *q);

#define mid_sched	((unsigned long) interruptible_sleep_on)

static int in_sh64_switch_to(unsigned long pc)
{
	extern char __sh64_switch_to_end;
	/* For a sleeping task, the PC is somewhere in the middle of the function,
	   so we don't have to worry about masking the LSB off */
	return (pc >= (unsigned long) sh64_switch_to) &&
	       (pc < (unsigned long) &__sh64_switch_to_end);
}

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long schedule_fp;
	unsigned long sh64_switch_to_fp;
	unsigned long schedule_caller_pc;
	unsigned long pc;

	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	/*
	 * The same comment as on the Alpha applies here, too ...
	 */
	pc = thread_saved_pc(p);

#ifdef CONFIG_FRAME_POINTER
	if (in_sh64_switch_to(pc)) {
		sh64_switch_to_fp = (long) p->thread.sp;
		/* r14 is saved at offset 4 in the sh64_switch_to frame */
		schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);

		/* and the caller of 'schedule' is (currently!) saved at offset 24
		   in the frame of schedule (from disasm) */
		schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
		return schedule_caller_pc;
	}
#endif
	return pc;
}

/* Provide a /proc/asids file that lists out the
   ASIDs currently associated with the processes.  (If the DM.PC register is
   examined through the debug link, this shows ASID + PC.  To make use of this,
   the PID->ASID relationship needs to be known.  This is primarily for
   debugging.)
   */

#if defined(CONFIG_SH64_PROC_ASIDS)
static int
asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
{
	int len=0;
	struct task_struct *p;
	read_lock(&tasklist_lock);
	for_each_process(p) {
		int pid = p->pid;

		if (!pid)
			continue;
		if (p->mm)
			len += sprintf(buf+len, "%5d : %02lx\n", pid,
				       asid_cache(smp_processor_id()));
		else
			len += sprintf(buf+len, "%5d : (none)\n", pid);
	}
	read_unlock(&tasklist_lock);
	*eof = 1;
	return len;
}

static int __init register_proc_asids(void)
{
	create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
	return 0;
}
__initcall(register_proc_asids);
#endif
OpenPOWER on IntegriCloud