xref: /linux/arch/powerpc/lib/sstep.c (revision 350779a29f11f80ac66a8b38a7718ad30f003f18)
1 /*
2  * Single-step support.
3  *
4  * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 #include <linux/kernel.h>
12 #include <linux/kprobes.h>
13 #include <linux/ptrace.h>
14 #include <linux/prefetch.h>
15 #include <asm/sstep.h>
16 #include <asm/processor.h>
17 #include <linux/uaccess.h>
18 #include <asm/cpu_has_feature.h>
19 #include <asm/cputable.h>
20 
21 extern char system_call_common[];
22 
23 #ifdef CONFIG_PPC64
24 /* Bits in SRR1 that are copied from MSR */
25 #define MSR_MASK	0xffffffff87c0ffffUL
26 #else
27 #define MSR_MASK	0x87c0ffff
28 #endif
29 
30 /* Bits in XER */
31 #define XER_SO		0x80000000U
32 #define XER_OV		0x40000000U
33 #define XER_CA		0x20000000U
34 
35 #ifdef CONFIG_PPC_FPU
36 /*
37  * Functions in ldstfp.S
38  */
39 extern int do_lfs(int rn, unsigned long ea);
40 extern int do_lfd(int rn, unsigned long ea);
41 extern int do_stfs(int rn, unsigned long ea);
42 extern int do_stfd(int rn, unsigned long ea);
43 extern int do_lvx(int rn, unsigned long ea);
44 extern int do_stvx(int rn, unsigned long ea);
45 extern void load_vsrn(int vsr, const void *p);
46 extern void store_vsrn(int vsr, void *p);
47 extern void conv_sp_to_dp(const float *sp, double *dp);
48 extern void conv_dp_to_sp(const double *dp, float *sp);
49 #endif
50 
51 #ifdef __powerpc64__
52 /*
53  * Functions in quad.S
54  */
55 extern int do_lq(unsigned long ea, unsigned long *regs);
56 extern int do_stq(unsigned long ea, unsigned long val0, unsigned long val1);
57 extern int do_lqarx(unsigned long ea, unsigned long *regs);
58 extern int do_stqcx(unsigned long ea, unsigned long val0, unsigned long val1,
59 		    unsigned int *crp);
60 #endif
61 
62 #ifdef __LITTLE_ENDIAN__
63 #define IS_LE	1
64 #define IS_BE	0
65 #else
66 #define IS_LE	0
67 #define IS_BE	1
68 #endif
69 
70 /*
71  * Emulate the truncation of 64 bit values in 32-bit mode.
72  */
73 static nokprobe_inline unsigned long truncate_if_32bit(unsigned long msr,
74 							unsigned long val)
75 {
76 #ifdef __powerpc64__
77 	if ((msr & MSR_64BIT) == 0)
78 		val &= 0xffffffffUL;
79 #endif
80 	return val;
81 }
82 
83 /*
84  * Determine whether a conditional branch instruction would branch.
85  */
86 static nokprobe_inline int branch_taken(unsigned int instr,
87 					const struct pt_regs *regs,
88 					struct instruction_op *op)
89 {
90 	unsigned int bo = (instr >> 21) & 0x1f;
91 	unsigned int bi;
92 
93 	if ((bo & 4) == 0) {
94 		/* decrement counter */
95 		op->type |= DECCTR;
96 		if (((bo >> 1) & 1) ^ (regs->ctr == 1))
97 			return 0;
98 	}
99 	if ((bo & 0x10) == 0) {
100 		/* check bit from CR */
101 		bi = (instr >> 16) & 0x1f;
102 		if (((regs->ccr >> (31 - bi)) & 1) != ((bo >> 3) & 1))
103 			return 0;
104 	}
105 	return 1;
106 }
107 
108 static nokprobe_inline long address_ok(struct pt_regs *regs, unsigned long ea, int nb)
109 {
110 	if (!user_mode(regs))
111 		return 1;
112 	return __access_ok(ea, nb, USER_DS);
113 }
114 
115 /*
116  * Calculate effective address for a D-form instruction
117  */
118 static nokprobe_inline unsigned long dform_ea(unsigned int instr,
119 					      const struct pt_regs *regs)
120 {
121 	int ra;
122 	unsigned long ea;
123 
124 	ra = (instr >> 16) & 0x1f;
125 	ea = (signed short) instr;		/* sign-extend */
126 	if (ra)
127 		ea += regs->gpr[ra];
128 
129 	return truncate_if_32bit(regs->msr, ea);
130 }
131 
132 #ifdef __powerpc64__
133 /*
134  * Calculate effective address for a DS-form instruction
135  */
136 static nokprobe_inline unsigned long dsform_ea(unsigned int instr,
137 					       const struct pt_regs *regs)
138 {
139 	int ra;
140 	unsigned long ea;
141 
142 	ra = (instr >> 16) & 0x1f;
143 	ea = (signed short) (instr & ~3);	/* sign-extend */
144 	if (ra)
145 		ea += regs->gpr[ra];
146 
147 	return truncate_if_32bit(regs->msr, ea);
148 }
149 
150 /*
151  * Calculate effective address for a DQ-form instruction
152  */
153 static nokprobe_inline unsigned long dqform_ea(unsigned int instr,
154 					       const struct pt_regs *regs)
155 {
156 	int ra;
157 	unsigned long ea;
158 
159 	ra = (instr >> 16) & 0x1f;
160 	ea = (signed short) (instr & ~0xf);	/* sign-extend */
161 	if (ra)
162 		ea += regs->gpr[ra];
163 
164 	return truncate_if_32bit(regs->msr, ea);
165 }
166 #endif /* __powerpc64 */
167 
168 /*
169  * Calculate effective address for an X-form instruction
170  */
171 static nokprobe_inline unsigned long xform_ea(unsigned int instr,
172 					      const struct pt_regs *regs)
173 {
174 	int ra, rb;
175 	unsigned long ea;
176 
177 	ra = (instr >> 16) & 0x1f;
178 	rb = (instr >> 11) & 0x1f;
179 	ea = regs->gpr[rb];
180 	if (ra)
181 		ea += regs->gpr[ra];
182 
183 	return truncate_if_32bit(regs->msr, ea);
184 }
185 
186 /*
187  * Return the largest power of 2, not greater than sizeof(unsigned long),
188  * such that x is a multiple of it.
189  */
190 static nokprobe_inline unsigned long max_align(unsigned long x)
191 {
192 	x |= sizeof(unsigned long);
193 	return x & -x;		/* isolates rightmost bit */
194 }
195 
196 
197 static nokprobe_inline unsigned long byterev_2(unsigned long x)
198 {
199 	return ((x >> 8) & 0xff) | ((x & 0xff) << 8);
200 }
201 
202 static nokprobe_inline unsigned long byterev_4(unsigned long x)
203 {
204 	return ((x >> 24) & 0xff) | ((x >> 8) & 0xff00) |
205 		((x & 0xff00) << 8) | ((x & 0xff) << 24);
206 }
207 
208 #ifdef __powerpc64__
209 static nokprobe_inline unsigned long byterev_8(unsigned long x)
210 {
211 	return (byterev_4(x) << 32) | byterev_4(x >> 32);
212 }
213 #endif
214 
215 static nokprobe_inline int read_mem_aligned(unsigned long *dest,
216 					unsigned long ea, int nb)
217 {
218 	int err = 0;
219 	unsigned long x = 0;
220 
221 	switch (nb) {
222 	case 1:
223 		err = __get_user(x, (unsigned char __user *) ea);
224 		break;
225 	case 2:
226 		err = __get_user(x, (unsigned short __user *) ea);
227 		break;
228 	case 4:
229 		err = __get_user(x, (unsigned int __user *) ea);
230 		break;
231 #ifdef __powerpc64__
232 	case 8:
233 		err = __get_user(x, (unsigned long __user *) ea);
234 		break;
235 #endif
236 	}
237 	if (!err)
238 		*dest = x;
239 	return err;
240 }
241 
242 static nokprobe_inline int read_mem_unaligned(unsigned long *dest,
243 				unsigned long ea, int nb, struct pt_regs *regs)
244 {
245 	int err;
246 	unsigned long x, b, c;
247 #ifdef __LITTLE_ENDIAN__
248 	int len = nb; /* save a copy of the length for byte reversal */
249 #endif
250 
251 	/* unaligned, do this in pieces */
252 	x = 0;
253 	for (; nb > 0; nb -= c) {
254 #ifdef __LITTLE_ENDIAN__
255 		c = 1;
256 #endif
257 #ifdef __BIG_ENDIAN__
258 		c = max_align(ea);
259 #endif
260 		if (c > nb)
261 			c = max_align(nb);
262 		err = read_mem_aligned(&b, ea, c);
263 		if (err)
264 			return err;
265 		x = (x << (8 * c)) + b;
266 		ea += c;
267 	}
268 #ifdef __LITTLE_ENDIAN__
269 	switch (len) {
270 	case 2:
271 		*dest = byterev_2(x);
272 		break;
273 	case 4:
274 		*dest = byterev_4(x);
275 		break;
276 #ifdef __powerpc64__
277 	case 8:
278 		*dest = byterev_8(x);
279 		break;
280 #endif
281 	}
282 #endif
283 #ifdef __BIG_ENDIAN__
284 	*dest = x;
285 #endif
286 	return 0;
287 }
288 
289 /*
290  * Read memory at address ea for nb bytes, return 0 for success
291  * or -EFAULT if an error occurred.
292  */
293 static int read_mem(unsigned long *dest, unsigned long ea, int nb,
294 			      struct pt_regs *regs)
295 {
296 	if (!address_ok(regs, ea, nb))
297 		return -EFAULT;
298 	if ((ea & (nb - 1)) == 0)
299 		return read_mem_aligned(dest, ea, nb);
300 	return read_mem_unaligned(dest, ea, nb, regs);
301 }
302 NOKPROBE_SYMBOL(read_mem);
303 
304 static nokprobe_inline int write_mem_aligned(unsigned long val,
305 					unsigned long ea, int nb)
306 {
307 	int err = 0;
308 
309 	switch (nb) {
310 	case 1:
311 		err = __put_user(val, (unsigned char __user *) ea);
312 		break;
313 	case 2:
314 		err = __put_user(val, (unsigned short __user *) ea);
315 		break;
316 	case 4:
317 		err = __put_user(val, (unsigned int __user *) ea);
318 		break;
319 #ifdef __powerpc64__
320 	case 8:
321 		err = __put_user(val, (unsigned long __user *) ea);
322 		break;
323 #endif
324 	}
325 	return err;
326 }
327 
328 static nokprobe_inline int write_mem_unaligned(unsigned long val,
329 				unsigned long ea, int nb, struct pt_regs *regs)
330 {
331 	int err;
332 	unsigned long c;
333 
334 #ifdef __LITTLE_ENDIAN__
335 	switch (nb) {
336 	case 2:
337 		val = byterev_2(val);
338 		break;
339 	case 4:
340 		val = byterev_4(val);
341 		break;
342 #ifdef __powerpc64__
343 	case 8:
344 		val = byterev_8(val);
345 		break;
346 #endif
347 	}
348 #endif
349 	/* unaligned or little-endian, do this in pieces */
350 	for (; nb > 0; nb -= c) {
351 #ifdef __LITTLE_ENDIAN__
352 		c = 1;
353 #endif
354 #ifdef __BIG_ENDIAN__
355 		c = max_align(ea);
356 #endif
357 		if (c > nb)
358 			c = max_align(nb);
359 		err = write_mem_aligned(val >> (nb - c) * 8, ea, c);
360 		if (err)
361 			return err;
362 		ea += c;
363 	}
364 	return 0;
365 }
366 
367 /*
368  * Write memory at address ea for nb bytes, return 0 for success
369  * or -EFAULT if an error occurred.
370  */
371 static int write_mem(unsigned long val, unsigned long ea, int nb,
372 			       struct pt_regs *regs)
373 {
374 	if (!address_ok(regs, ea, nb))
375 		return -EFAULT;
376 	if ((ea & (nb - 1)) == 0)
377 		return write_mem_aligned(val, ea, nb);
378 	return write_mem_unaligned(val, ea, nb, regs);
379 }
380 NOKPROBE_SYMBOL(write_mem);
381 
382 #ifdef CONFIG_PPC_FPU
383 /*
384  * Check the address and alignment, and call func to do the actual
385  * load or store.
386  */
387 static int do_fp_load(int rn, int (*func)(int, unsigned long),
388 				unsigned long ea, int nb,
389 				struct pt_regs *regs)
390 {
391 	int err;
392 	union {
393 		double dbl;
394 		unsigned long ul[2];
395 		struct {
396 #ifdef __BIG_ENDIAN__
397 			unsigned _pad_;
398 			unsigned word;
399 #endif
400 #ifdef __LITTLE_ENDIAN__
401 			unsigned word;
402 			unsigned _pad_;
403 #endif
404 		} single;
405 	} data;
406 	unsigned long ptr;
407 
408 	if (!address_ok(regs, ea, nb))
409 		return -EFAULT;
410 	if ((ea & 3) == 0)
411 		return (*func)(rn, ea);
412 	ptr = (unsigned long) &data.ul;
413 	if (sizeof(unsigned long) == 8 || nb == 4) {
414 		err = read_mem_unaligned(&data.ul[0], ea, nb, regs);
415 		if (nb == 4)
416 			ptr = (unsigned long)&(data.single.word);
417 	} else {
418 		/* reading a double on 32-bit */
419 		err = read_mem_unaligned(&data.ul[0], ea, 4, regs);
420 		if (!err)
421 			err = read_mem_unaligned(&data.ul[1], ea + 4, 4, regs);
422 	}
423 	if (err)
424 		return err;
425 	return (*func)(rn, ptr);
426 }
427 NOKPROBE_SYMBOL(do_fp_load);
428 
429 static int do_fp_store(int rn, int (*func)(int, unsigned long),
430 				 unsigned long ea, int nb,
431 				 struct pt_regs *regs)
432 {
433 	int err;
434 	union {
435 		double dbl;
436 		unsigned long ul[2];
437 		struct {
438 #ifdef __BIG_ENDIAN__
439 			unsigned _pad_;
440 			unsigned word;
441 #endif
442 #ifdef __LITTLE_ENDIAN__
443 			unsigned word;
444 			unsigned _pad_;
445 #endif
446 		} single;
447 	} data;
448 	unsigned long ptr;
449 
450 	if (!address_ok(regs, ea, nb))
451 		return -EFAULT;
452 	if ((ea & 3) == 0)
453 		return (*func)(rn, ea);
454 	ptr = (unsigned long) &data.ul[0];
455 	if (sizeof(unsigned long) == 8 || nb == 4) {
456 		if (nb == 4)
457 			ptr = (unsigned long)&(data.single.word);
458 		err = (*func)(rn, ptr);
459 		if (err)
460 			return err;
461 		err = write_mem_unaligned(data.ul[0], ea, nb, regs);
462 	} else {
463 		/* writing a double on 32-bit */
464 		err = (*func)(rn, ptr);
465 		if (err)
466 			return err;
467 		err = write_mem_unaligned(data.ul[0], ea, 4, regs);
468 		if (!err)
469 			err = write_mem_unaligned(data.ul[1], ea + 4, 4, regs);
470 	}
471 	return err;
472 }
473 NOKPROBE_SYMBOL(do_fp_store);
474 #endif
475 
476 #ifdef CONFIG_ALTIVEC
477 /* For Altivec/VMX, no need to worry about alignment */
478 static nokprobe_inline int do_vec_load(int rn, int (*func)(int, unsigned long),
479 				 unsigned long ea, struct pt_regs *regs)
480 {
481 	if (!address_ok(regs, ea & ~0xfUL, 16))
482 		return -EFAULT;
483 	return (*func)(rn, ea);
484 }
485 
486 static nokprobe_inline int do_vec_store(int rn, int (*func)(int, unsigned long),
487 				  unsigned long ea, struct pt_regs *regs)
488 {
489 	if (!address_ok(regs, ea & ~0xfUL, 16))
490 		return -EFAULT;
491 	return (*func)(rn, ea);
492 }
493 #endif /* CONFIG_ALTIVEC */
494 
495 #ifdef __powerpc64__
496 static nokprobe_inline int emulate_lq(struct pt_regs *regs, unsigned long ea,
497 				      int reg)
498 {
499 	int err;
500 
501 	if (!address_ok(regs, ea, 16))
502 		return -EFAULT;
503 	/* if aligned, should be atomic */
504 	if ((ea & 0xf) == 0)
505 		return do_lq(ea, &regs->gpr[reg]);
506 
507 	err = read_mem(&regs->gpr[reg + IS_LE], ea, 8, regs);
508 	if (!err)
509 		err = read_mem(&regs->gpr[reg + IS_BE], ea + 8, 8, regs);
510 	return err;
511 }
512 
513 static nokprobe_inline int emulate_stq(struct pt_regs *regs, unsigned long ea,
514 				       int reg)
515 {
516 	int err;
517 
518 	if (!address_ok(regs, ea, 16))
519 		return -EFAULT;
520 	/* if aligned, should be atomic */
521 	if ((ea & 0xf) == 0)
522 		return do_stq(ea, regs->gpr[reg], regs->gpr[reg + 1]);
523 
524 	err = write_mem(regs->gpr[reg + IS_LE], ea, 8, regs);
525 	if (!err)
526 		err = write_mem(regs->gpr[reg + IS_BE], ea + 8, 8, regs);
527 	return err;
528 }
529 #endif /* __powerpc64 */
530 
531 #ifdef CONFIG_VSX
532 void emulate_vsx_load(struct instruction_op *op, union vsx_reg *reg,
533 		      const void *mem)
534 {
535 	int size, read_size;
536 	int i, j;
537 	const unsigned int *wp;
538 	const unsigned short *hp;
539 	const unsigned char *bp;
540 
541 	size = GETSIZE(op->type);
542 	reg->d[0] = reg->d[1] = 0;
543 
544 	switch (op->element_size) {
545 	case 16:
546 		/* whole vector; lxv[x] or lxvl[l] */
547 		if (size == 0)
548 			break;
549 		memcpy(reg, mem, size);
550 		if (IS_LE && (op->vsx_flags & VSX_LDLEFT)) {
551 			/* reverse 16 bytes */
552 			unsigned long tmp;
553 			tmp = byterev_8(reg->d[0]);
554 			reg->d[0] = byterev_8(reg->d[1]);
555 			reg->d[1] = tmp;
556 		}
557 		break;
558 	case 8:
559 		/* scalar loads, lxvd2x, lxvdsx */
560 		read_size = (size >= 8) ? 8 : size;
561 		i = IS_LE ? 8 : 8 - read_size;
562 		memcpy(&reg->b[i], mem, read_size);
563 		if (size < 8) {
564 			if (op->type & SIGNEXT) {
565 				/* size == 4 is the only case here */
566 				reg->d[IS_LE] = (signed int) reg->d[IS_LE];
567 			} else if (op->vsx_flags & VSX_FPCONV) {
568 				preempt_disable();
569 				conv_sp_to_dp(&reg->fp[1 + IS_LE],
570 					      &reg->dp[IS_LE]);
571 				preempt_enable();
572 			}
573 		} else {
574 			if (size == 16)
575 				reg->d[IS_BE] = *(unsigned long *)(mem + 8);
576 			else if (op->vsx_flags & VSX_SPLAT)
577 				reg->d[IS_BE] = reg->d[IS_LE];
578 		}
579 		break;
580 	case 4:
581 		/* lxvw4x, lxvwsx */
582 		wp = mem;
583 		for (j = 0; j < size / 4; ++j) {
584 			i = IS_LE ? 3 - j : j;
585 			reg->w[i] = *wp++;
586 		}
587 		if (op->vsx_flags & VSX_SPLAT) {
588 			u32 val = reg->w[IS_LE ? 3 : 0];
589 			for (; j < 4; ++j) {
590 				i = IS_LE ? 3 - j : j;
591 				reg->w[i] = val;
592 			}
593 		}
594 		break;
595 	case 2:
596 		/* lxvh8x */
597 		hp = mem;
598 		for (j = 0; j < size / 2; ++j) {
599 			i = IS_LE ? 7 - j : j;
600 			reg->h[i] = *hp++;
601 		}
602 		break;
603 	case 1:
604 		/* lxvb16x */
605 		bp = mem;
606 		for (j = 0; j < size; ++j) {
607 			i = IS_LE ? 15 - j : j;
608 			reg->b[i] = *bp++;
609 		}
610 		break;
611 	}
612 }
613 EXPORT_SYMBOL_GPL(emulate_vsx_load);
614 NOKPROBE_SYMBOL(emulate_vsx_load);
615 
616 void emulate_vsx_store(struct instruction_op *op, const union vsx_reg *reg,
617 		       void *mem)
618 {
619 	int size, write_size;
620 	int i, j;
621 	union vsx_reg buf;
622 	unsigned int *wp;
623 	unsigned short *hp;
624 	unsigned char *bp;
625 
626 	size = GETSIZE(op->type);
627 
628 	switch (op->element_size) {
629 	case 16:
630 		/* stxv, stxvx, stxvl, stxvll */
631 		if (size == 0)
632 			break;
633 		if (IS_LE && (op->vsx_flags & VSX_LDLEFT)) {
634 			/* reverse 16 bytes */
635 			buf.d[0] = byterev_8(reg->d[1]);
636 			buf.d[1] = byterev_8(reg->d[0]);
637 			reg = &buf;
638 		}
639 		memcpy(mem, reg, size);
640 		break;
641 	case 8:
642 		/* scalar stores, stxvd2x */
643 		write_size = (size >= 8) ? 8 : size;
644 		i = IS_LE ? 8 : 8 - write_size;
645 		if (size < 8 && op->vsx_flags & VSX_FPCONV) {
646 			buf.d[0] = buf.d[1] = 0;
647 			preempt_disable();
648 			conv_dp_to_sp(&reg->dp[IS_LE], &buf.fp[1 + IS_LE]);
649 			preempt_enable();
650 			reg = &buf;
651 		}
652 		memcpy(mem, &reg->b[i], write_size);
653 		if (size == 16)
654 			memcpy(mem + 8, &reg->d[IS_BE], 8);
655 		break;
656 	case 4:
657 		/* stxvw4x */
658 		wp = mem;
659 		for (j = 0; j < size / 4; ++j) {
660 			i = IS_LE ? 3 - j : j;
661 			*wp++ = reg->w[i];
662 		}
663 		break;
664 	case 2:
665 		/* stxvh8x */
666 		hp = mem;
667 		for (j = 0; j < size / 2; ++j) {
668 			i = IS_LE ? 7 - j : j;
669 			*hp++ = reg->h[i];
670 		}
671 		break;
672 	case 1:
673 		/* stvxb16x */
674 		bp = mem;
675 		for (j = 0; j < size; ++j) {
676 			i = IS_LE ? 15 - j : j;
677 			*bp++ = reg->b[i];
678 		}
679 		break;
680 	}
681 }
682 EXPORT_SYMBOL_GPL(emulate_vsx_store);
683 NOKPROBE_SYMBOL(emulate_vsx_store);
684 #endif /* CONFIG_VSX */
685 
686 #define __put_user_asmx(x, addr, err, op, cr)		\
687 	__asm__ __volatile__(				\
688 		"1:	" op " %2,0,%3\n"		\
689 		"	mfcr	%1\n"			\
690 		"2:\n"					\
691 		".section .fixup,\"ax\"\n"		\
692 		"3:	li	%0,%4\n"		\
693 		"	b	2b\n"			\
694 		".previous\n"				\
695 		EX_TABLE(1b, 3b)			\
696 		: "=r" (err), "=r" (cr)			\
697 		: "r" (x), "r" (addr), "i" (-EFAULT), "0" (err))
698 
699 #define __get_user_asmx(x, addr, err, op)		\
700 	__asm__ __volatile__(				\
701 		"1:	"op" %1,0,%2\n"			\
702 		"2:\n"					\
703 		".section .fixup,\"ax\"\n"		\
704 		"3:	li	%0,%3\n"		\
705 		"	b	2b\n"			\
706 		".previous\n"				\
707 		EX_TABLE(1b, 3b)			\
708 		: "=r" (err), "=r" (x)			\
709 		: "r" (addr), "i" (-EFAULT), "0" (err))
710 
711 #define __cacheop_user_asmx(addr, err, op)		\
712 	__asm__ __volatile__(				\
713 		"1:	"op" 0,%1\n"			\
714 		"2:\n"					\
715 		".section .fixup,\"ax\"\n"		\
716 		"3:	li	%0,%3\n"		\
717 		"	b	2b\n"			\
718 		".previous\n"				\
719 		EX_TABLE(1b, 3b)			\
720 		: "=r" (err)				\
721 		: "r" (addr), "i" (-EFAULT), "0" (err))
722 
723 static nokprobe_inline void set_cr0(const struct pt_regs *regs,
724 				    struct instruction_op *op, int rd)
725 {
726 	long val = regs->gpr[rd];
727 
728 	op->type |= SETCC;
729 	op->ccval = (regs->ccr & 0x0fffffff) | ((regs->xer >> 3) & 0x10000000);
730 #ifdef __powerpc64__
731 	if (!(regs->msr & MSR_64BIT))
732 		val = (int) val;
733 #endif
734 	if (val < 0)
735 		op->ccval |= 0x80000000;
736 	else if (val > 0)
737 		op->ccval |= 0x40000000;
738 	else
739 		op->ccval |= 0x20000000;
740 }
741 
742 static nokprobe_inline void add_with_carry(const struct pt_regs *regs,
743 				     struct instruction_op *op, int rd,
744 				     unsigned long val1, unsigned long val2,
745 				     unsigned long carry_in)
746 {
747 	unsigned long val = val1 + val2;
748 
749 	if (carry_in)
750 		++val;
751 	op->type = COMPUTE + SETREG + SETXER;
752 	op->reg = rd;
753 	op->val = val;
754 #ifdef __powerpc64__
755 	if (!(regs->msr & MSR_64BIT)) {
756 		val = (unsigned int) val;
757 		val1 = (unsigned int) val1;
758 	}
759 #endif
760 	op->xerval = regs->xer;
761 	if (val < val1 || (carry_in && val == val1))
762 		op->xerval |= XER_CA;
763 	else
764 		op->xerval &= ~XER_CA;
765 }
766 
767 static nokprobe_inline void do_cmp_signed(const struct pt_regs *regs,
768 					  struct instruction_op *op,
769 					  long v1, long v2, int crfld)
770 {
771 	unsigned int crval, shift;
772 
773 	op->type = COMPUTE + SETCC;
774 	crval = (regs->xer >> 31) & 1;		/* get SO bit */
775 	if (v1 < v2)
776 		crval |= 8;
777 	else if (v1 > v2)
778 		crval |= 4;
779 	else
780 		crval |= 2;
781 	shift = (7 - crfld) * 4;
782 	op->ccval = (regs->ccr & ~(0xf << shift)) | (crval << shift);
783 }
784 
785 static nokprobe_inline void do_cmp_unsigned(const struct pt_regs *regs,
786 					    struct instruction_op *op,
787 					    unsigned long v1,
788 					    unsigned long v2, int crfld)
789 {
790 	unsigned int crval, shift;
791 
792 	op->type = COMPUTE + SETCC;
793 	crval = (regs->xer >> 31) & 1;		/* get SO bit */
794 	if (v1 < v2)
795 		crval |= 8;
796 	else if (v1 > v2)
797 		crval |= 4;
798 	else
799 		crval |= 2;
800 	shift = (7 - crfld) * 4;
801 	op->ccval = (regs->ccr & ~(0xf << shift)) | (crval << shift);
802 }
803 
804 static nokprobe_inline void do_cmpb(const struct pt_regs *regs,
805 				    struct instruction_op *op,
806 				    unsigned long v1, unsigned long v2)
807 {
808 	unsigned long long out_val, mask;
809 	int i;
810 
811 	out_val = 0;
812 	for (i = 0; i < 8; i++) {
813 		mask = 0xffUL << (i * 8);
814 		if ((v1 & mask) == (v2 & mask))
815 			out_val |= mask;
816 	}
817 	op->val = out_val;
818 }
819 
820 /*
821  * The size parameter is used to adjust the equivalent popcnt instruction.
822  * popcntb = 8, popcntw = 32, popcntd = 64
823  */
824 static nokprobe_inline void do_popcnt(const struct pt_regs *regs,
825 				      struct instruction_op *op,
826 				      unsigned long v1, int size)
827 {
828 	unsigned long long out = v1;
829 
830 	out -= (out >> 1) & 0x5555555555555555;
831 	out = (0x3333333333333333 & out) + (0x3333333333333333 & (out >> 2));
832 	out = (out + (out >> 4)) & 0x0f0f0f0f0f0f0f0f;
833 
834 	if (size == 8) {	/* popcntb */
835 		op->val = out;
836 		return;
837 	}
838 	out += out >> 8;
839 	out += out >> 16;
840 	if (size == 32) {	/* popcntw */
841 		op->val = out & 0x0000003f0000003f;
842 		return;
843 	}
844 
845 	out = (out + (out >> 32)) & 0x7f;
846 	op->val = out;	/* popcntd */
847 }
848 
849 #ifdef CONFIG_PPC64
850 static nokprobe_inline void do_bpermd(const struct pt_regs *regs,
851 				      struct instruction_op *op,
852 				      unsigned long v1, unsigned long v2)
853 {
854 	unsigned char perm, idx;
855 	unsigned int i;
856 
857 	perm = 0;
858 	for (i = 0; i < 8; i++) {
859 		idx = (v1 >> (i * 8)) & 0xff;
860 		if (idx < 64)
861 			if (v2 & PPC_BIT(idx))
862 				perm |= 1 << i;
863 	}
864 	op->val = perm;
865 }
866 #endif /* CONFIG_PPC64 */
867 /*
868  * The size parameter adjusts the equivalent prty instruction.
869  * prtyw = 32, prtyd = 64
870  */
871 static nokprobe_inline void do_prty(const struct pt_regs *regs,
872 				    struct instruction_op *op,
873 				    unsigned long v, int size)
874 {
875 	unsigned long long res = v ^ (v >> 8);
876 
877 	res ^= res >> 16;
878 	if (size == 32) {		/* prtyw */
879 		op->val = res & 0x0000000100000001;
880 		return;
881 	}
882 
883 	res ^= res >> 32;
884 	op->val = res & 1;	/*prtyd */
885 }
886 
887 static nokprobe_inline int trap_compare(long v1, long v2)
888 {
889 	int ret = 0;
890 
891 	if (v1 < v2)
892 		ret |= 0x10;
893 	else if (v1 > v2)
894 		ret |= 0x08;
895 	else
896 		ret |= 0x04;
897 	if ((unsigned long)v1 < (unsigned long)v2)
898 		ret |= 0x02;
899 	else if ((unsigned long)v1 > (unsigned long)v2)
900 		ret |= 0x01;
901 	return ret;
902 }
903 
904 /*
905  * Elements of 32-bit rotate and mask instructions.
906  */
907 #define MASK32(mb, me)	((0xffffffffUL >> (mb)) + \
908 			 ((signed long)-0x80000000L >> (me)) + ((me) >= (mb)))
909 #ifdef __powerpc64__
910 #define MASK64_L(mb)	(~0UL >> (mb))
911 #define MASK64_R(me)	((signed long)-0x8000000000000000L >> (me))
912 #define MASK64(mb, me)	(MASK64_L(mb) + MASK64_R(me) + ((me) >= (mb)))
913 #define DATA32(x)	(((x) & 0xffffffffUL) | (((x) & 0xffffffffUL) << 32))
914 #else
915 #define DATA32(x)	(x)
916 #endif
917 #define ROTATE(x, n)	((n) ? (((x) << (n)) | ((x) >> (8 * sizeof(long) - (n)))) : (x))
918 
919 /*
920  * Decode an instruction, and return information about it in *op
921  * without changing *regs.
922  * Integer arithmetic and logical instructions, branches, and barrier
923  * instructions can be emulated just using the information in *op.
924  *
925  * Return value is 1 if the instruction can be emulated just by
926  * updating *regs with the information in *op, -1 if we need the
927  * GPRs but *regs doesn't contain the full register set, or 0
928  * otherwise.
929  */
930 int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
931 		  unsigned int instr)
932 {
933 	unsigned int opcode, ra, rb, rd, spr, u;
934 	unsigned long int imm;
935 	unsigned long int val, val2;
936 	unsigned int mb, me, sh;
937 	long ival;
938 
939 	op->type = COMPUTE;
940 
941 	opcode = instr >> 26;
942 	switch (opcode) {
943 	case 16:	/* bc */
944 		op->type = BRANCH;
945 		imm = (signed short)(instr & 0xfffc);
946 		if ((instr & 2) == 0)
947 			imm += regs->nip;
948 		op->val = truncate_if_32bit(regs->msr, imm);
949 		if (instr & 1)
950 			op->type |= SETLK;
951 		if (branch_taken(instr, regs, op))
952 			op->type |= BRTAKEN;
953 		return 1;
954 #ifdef CONFIG_PPC64
955 	case 17:	/* sc */
956 		if ((instr & 0xfe2) == 2)
957 			op->type = SYSCALL;
958 		else
959 			op->type = UNKNOWN;
960 		return 0;
961 #endif
962 	case 18:	/* b */
963 		op->type = BRANCH | BRTAKEN;
964 		imm = instr & 0x03fffffc;
965 		if (imm & 0x02000000)
966 			imm -= 0x04000000;
967 		if ((instr & 2) == 0)
968 			imm += regs->nip;
969 		op->val = truncate_if_32bit(regs->msr, imm);
970 		if (instr & 1)
971 			op->type |= SETLK;
972 		return 1;
973 	case 19:
974 		switch ((instr >> 1) & 0x3ff) {
975 		case 0:		/* mcrf */
976 			op->type = COMPUTE + SETCC;
977 			rd = 7 - ((instr >> 23) & 0x7);
978 			ra = 7 - ((instr >> 18) & 0x7);
979 			rd *= 4;
980 			ra *= 4;
981 			val = (regs->ccr >> ra) & 0xf;
982 			op->ccval = (regs->ccr & ~(0xfUL << rd)) | (val << rd);
983 			return 1;
984 
985 		case 16:	/* bclr */
986 		case 528:	/* bcctr */
987 			op->type = BRANCH;
988 			imm = (instr & 0x400)? regs->ctr: regs->link;
989 			op->val = truncate_if_32bit(regs->msr, imm);
990 			if (instr & 1)
991 				op->type |= SETLK;
992 			if (branch_taken(instr, regs, op))
993 				op->type |= BRTAKEN;
994 			return 1;
995 
996 		case 18:	/* rfid, scary */
997 			if (regs->msr & MSR_PR)
998 				goto priv;
999 			op->type = RFI;
1000 			return 0;
1001 
1002 		case 150:	/* isync */
1003 			op->type = BARRIER | BARRIER_ISYNC;
1004 			return 1;
1005 
1006 		case 33:	/* crnor */
1007 		case 129:	/* crandc */
1008 		case 193:	/* crxor */
1009 		case 225:	/* crnand */
1010 		case 257:	/* crand */
1011 		case 289:	/* creqv */
1012 		case 417:	/* crorc */
1013 		case 449:	/* cror */
1014 			op->type = COMPUTE + SETCC;
1015 			ra = (instr >> 16) & 0x1f;
1016 			rb = (instr >> 11) & 0x1f;
1017 			rd = (instr >> 21) & 0x1f;
1018 			ra = (regs->ccr >> (31 - ra)) & 1;
1019 			rb = (regs->ccr >> (31 - rb)) & 1;
1020 			val = (instr >> (6 + ra * 2 + rb)) & 1;
1021 			op->ccval = (regs->ccr & ~(1UL << (31 - rd))) |
1022 				(val << (31 - rd));
1023 			return 1;
1024 		default:
1025 			op->type = UNKNOWN;
1026 			return 0;
1027 		}
1028 		break;
1029 	case 31:
1030 		switch ((instr >> 1) & 0x3ff) {
1031 		case 598:	/* sync */
1032 			op->type = BARRIER + BARRIER_SYNC;
1033 #ifdef __powerpc64__
1034 			switch ((instr >> 21) & 3) {
1035 			case 1:		/* lwsync */
1036 				op->type = BARRIER + BARRIER_LWSYNC;
1037 				break;
1038 			case 2:		/* ptesync */
1039 				op->type = BARRIER + BARRIER_PTESYNC;
1040 				break;
1041 			}
1042 #endif
1043 			return 1;
1044 
1045 		case 854:	/* eieio */
1046 			op->type = BARRIER + BARRIER_EIEIO;
1047 			return 1;
1048 		}
1049 		break;
1050 	}
1051 
1052 	/* Following cases refer to regs->gpr[], so we need all regs */
1053 	if (!FULL_REGS(regs))
1054 		return -1;
1055 
1056 	rd = (instr >> 21) & 0x1f;
1057 	ra = (instr >> 16) & 0x1f;
1058 	rb = (instr >> 11) & 0x1f;
1059 
1060 	switch (opcode) {
1061 #ifdef __powerpc64__
1062 	case 2:		/* tdi */
1063 		if (rd & trap_compare(regs->gpr[ra], (short) instr))
1064 			goto trap;
1065 		return 1;
1066 #endif
1067 	case 3:		/* twi */
1068 		if (rd & trap_compare((int)regs->gpr[ra], (short) instr))
1069 			goto trap;
1070 		return 1;
1071 
1072 	case 7:		/* mulli */
1073 		op->val = regs->gpr[ra] * (short) instr;
1074 		goto compute_done;
1075 
1076 	case 8:		/* subfic */
1077 		imm = (short) instr;
1078 		add_with_carry(regs, op, rd, ~regs->gpr[ra], imm, 1);
1079 		return 1;
1080 
1081 	case 10:	/* cmpli */
1082 		imm = (unsigned short) instr;
1083 		val = regs->gpr[ra];
1084 #ifdef __powerpc64__
1085 		if ((rd & 1) == 0)
1086 			val = (unsigned int) val;
1087 #endif
1088 		do_cmp_unsigned(regs, op, val, imm, rd >> 2);
1089 		return 1;
1090 
1091 	case 11:	/* cmpi */
1092 		imm = (short) instr;
1093 		val = regs->gpr[ra];
1094 #ifdef __powerpc64__
1095 		if ((rd & 1) == 0)
1096 			val = (int) val;
1097 #endif
1098 		do_cmp_signed(regs, op, val, imm, rd >> 2);
1099 		return 1;
1100 
1101 	case 12:	/* addic */
1102 		imm = (short) instr;
1103 		add_with_carry(regs, op, rd, regs->gpr[ra], imm, 0);
1104 		return 1;
1105 
1106 	case 13:	/* addic. */
1107 		imm = (short) instr;
1108 		add_with_carry(regs, op, rd, regs->gpr[ra], imm, 0);
1109 		set_cr0(regs, op, rd);
1110 		return 1;
1111 
1112 	case 14:	/* addi */
1113 		imm = (short) instr;
1114 		if (ra)
1115 			imm += regs->gpr[ra];
1116 		op->val = imm;
1117 		goto compute_done;
1118 
1119 	case 15:	/* addis */
1120 		imm = ((short) instr) << 16;
1121 		if (ra)
1122 			imm += regs->gpr[ra];
1123 		op->val = imm;
1124 		goto compute_done;
1125 
1126 	case 20:	/* rlwimi */
1127 		mb = (instr >> 6) & 0x1f;
1128 		me = (instr >> 1) & 0x1f;
1129 		val = DATA32(regs->gpr[rd]);
1130 		imm = MASK32(mb, me);
1131 		op->val = (regs->gpr[ra] & ~imm) | (ROTATE(val, rb) & imm);
1132 		goto logical_done;
1133 
1134 	case 21:	/* rlwinm */
1135 		mb = (instr >> 6) & 0x1f;
1136 		me = (instr >> 1) & 0x1f;
1137 		val = DATA32(regs->gpr[rd]);
1138 		op->val = ROTATE(val, rb) & MASK32(mb, me);
1139 		goto logical_done;
1140 
1141 	case 23:	/* rlwnm */
1142 		mb = (instr >> 6) & 0x1f;
1143 		me = (instr >> 1) & 0x1f;
1144 		rb = regs->gpr[rb] & 0x1f;
1145 		val = DATA32(regs->gpr[rd]);
1146 		op->val = ROTATE(val, rb) & MASK32(mb, me);
1147 		goto logical_done;
1148 
1149 	case 24:	/* ori */
1150 		op->val = regs->gpr[rd] | (unsigned short) instr;
1151 		goto logical_done_nocc;
1152 
1153 	case 25:	/* oris */
1154 		imm = (unsigned short) instr;
1155 		op->val = regs->gpr[rd] | (imm << 16);
1156 		goto logical_done_nocc;
1157 
1158 	case 26:	/* xori */
1159 		op->val = regs->gpr[rd] ^ (unsigned short) instr;
1160 		goto logical_done_nocc;
1161 
1162 	case 27:	/* xoris */
1163 		imm = (unsigned short) instr;
1164 		op->val = regs->gpr[rd] ^ (imm << 16);
1165 		goto logical_done_nocc;
1166 
1167 	case 28:	/* andi. */
1168 		op->val = regs->gpr[rd] & (unsigned short) instr;
1169 		set_cr0(regs, op, ra);
1170 		goto logical_done_nocc;
1171 
1172 	case 29:	/* andis. */
1173 		imm = (unsigned short) instr;
1174 		op->val = regs->gpr[rd] & (imm << 16);
1175 		set_cr0(regs, op, ra);
1176 		goto logical_done_nocc;
1177 
1178 #ifdef __powerpc64__
1179 	case 30:	/* rld* */
1180 		mb = ((instr >> 6) & 0x1f) | (instr & 0x20);
1181 		val = regs->gpr[rd];
1182 		if ((instr & 0x10) == 0) {
1183 			sh = rb | ((instr & 2) << 4);
1184 			val = ROTATE(val, sh);
1185 			switch ((instr >> 2) & 3) {
1186 			case 0:		/* rldicl */
1187 				val &= MASK64_L(mb);
1188 				break;
1189 			case 1:		/* rldicr */
1190 				val &= MASK64_R(mb);
1191 				break;
1192 			case 2:		/* rldic */
1193 				val &= MASK64(mb, 63 - sh);
1194 				break;
1195 			case 3:		/* rldimi */
1196 				imm = MASK64(mb, 63 - sh);
1197 				val = (regs->gpr[ra] & ~imm) |
1198 					(val & imm);
1199 			}
1200 			op->val = val;
1201 			goto logical_done;
1202 		} else {
1203 			sh = regs->gpr[rb] & 0x3f;
1204 			val = ROTATE(val, sh);
1205 			switch ((instr >> 1) & 7) {
1206 			case 0:		/* rldcl */
1207 				op->val = val & MASK64_L(mb);
1208 				goto logical_done;
1209 			case 1:		/* rldcr */
1210 				op->val = val & MASK64_R(mb);
1211 				goto logical_done;
1212 			}
1213 		}
1214 #endif
1215 		op->type = UNKNOWN;	/* illegal instruction */
1216 		return 0;
1217 
1218 	case 31:
1219 		switch ((instr >> 1) & 0x3ff) {
1220 		case 4:		/* tw */
1221 			if (rd == 0x1f ||
1222 			    (rd & trap_compare((int)regs->gpr[ra],
1223 					       (int)regs->gpr[rb])))
1224 				goto trap;
1225 			return 1;
1226 #ifdef __powerpc64__
1227 		case 68:	/* td */
1228 			if (rd & trap_compare(regs->gpr[ra], regs->gpr[rb]))
1229 				goto trap;
1230 			return 1;
1231 #endif
1232 		case 83:	/* mfmsr */
1233 			if (regs->msr & MSR_PR)
1234 				goto priv;
1235 			op->type = MFMSR;
1236 			op->reg = rd;
1237 			return 0;
1238 		case 146:	/* mtmsr */
1239 			if (regs->msr & MSR_PR)
1240 				goto priv;
1241 			op->type = MTMSR;
1242 			op->reg = rd;
1243 			op->val = 0xffffffff & ~(MSR_ME | MSR_LE);
1244 			return 0;
1245 #ifdef CONFIG_PPC64
1246 		case 178:	/* mtmsrd */
1247 			if (regs->msr & MSR_PR)
1248 				goto priv;
1249 			op->type = MTMSR;
1250 			op->reg = rd;
1251 			/* only MSR_EE and MSR_RI get changed if bit 15 set */
1252 			/* mtmsrd doesn't change MSR_HV, MSR_ME or MSR_LE */
1253 			imm = (instr & 0x10000)? 0x8002: 0xefffffffffffeffeUL;
1254 			op->val = imm;
1255 			return 0;
1256 #endif
1257 
1258 		case 19:	/* mfcr */
1259 			imm = 0xffffffffUL;
1260 			if ((instr >> 20) & 1) {
1261 				imm = 0xf0000000UL;
1262 				for (sh = 0; sh < 8; ++sh) {
1263 					if (instr & (0x80000 >> sh))
1264 						break;
1265 					imm >>= 4;
1266 				}
1267 			}
1268 			op->val = regs->ccr & imm;
1269 			goto compute_done;
1270 
1271 		case 144:	/* mtcrf */
1272 			op->type = COMPUTE + SETCC;
1273 			imm = 0xf0000000UL;
1274 			val = regs->gpr[rd];
1275 			op->val = regs->ccr;
1276 			for (sh = 0; sh < 8; ++sh) {
1277 				if (instr & (0x80000 >> sh))
1278 					op->val = (op->val & ~imm) |
1279 						(val & imm);
1280 				imm >>= 4;
1281 			}
1282 			return 1;
1283 
1284 		case 339:	/* mfspr */
1285 			spr = ((instr >> 16) & 0x1f) | ((instr >> 6) & 0x3e0);
1286 			op->type = MFSPR;
1287 			op->reg = rd;
1288 			op->spr = spr;
1289 			if (spr == SPRN_XER || spr == SPRN_LR ||
1290 			    spr == SPRN_CTR)
1291 				return 1;
1292 			return 0;
1293 
1294 		case 467:	/* mtspr */
1295 			spr = ((instr >> 16) & 0x1f) | ((instr >> 6) & 0x3e0);
1296 			op->type = MTSPR;
1297 			op->val = regs->gpr[rd];
1298 			op->spr = spr;
1299 			if (spr == SPRN_XER || spr == SPRN_LR ||
1300 			    spr == SPRN_CTR)
1301 				return 1;
1302 			return 0;
1303 
1304 /*
1305  * Compare instructions
1306  */
1307 		case 0:	/* cmp */
1308 			val = regs->gpr[ra];
1309 			val2 = regs->gpr[rb];
1310 #ifdef __powerpc64__
1311 			if ((rd & 1) == 0) {
1312 				/* word (32-bit) compare */
1313 				val = (int) val;
1314 				val2 = (int) val2;
1315 			}
1316 #endif
1317 			do_cmp_signed(regs, op, val, val2, rd >> 2);
1318 			return 1;
1319 
1320 		case 32:	/* cmpl */
1321 			val = regs->gpr[ra];
1322 			val2 = regs->gpr[rb];
1323 #ifdef __powerpc64__
1324 			if ((rd & 1) == 0) {
1325 				/* word (32-bit) compare */
1326 				val = (unsigned int) val;
1327 				val2 = (unsigned int) val2;
1328 			}
1329 #endif
1330 			do_cmp_unsigned(regs, op, val, val2, rd >> 2);
1331 			return 1;
1332 
1333 		case 508: /* cmpb */
1334 			do_cmpb(regs, op, regs->gpr[rd], regs->gpr[rb]);
1335 			goto logical_done_nocc;
1336 
1337 /*
1338  * Arithmetic instructions
1339  */
1340 		case 8:	/* subfc */
1341 			add_with_carry(regs, op, rd, ~regs->gpr[ra],
1342 				       regs->gpr[rb], 1);
1343 			goto arith_done;
1344 #ifdef __powerpc64__
1345 		case 9:	/* mulhdu */
1346 			asm("mulhdu %0,%1,%2" : "=r" (op->val) :
1347 			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
1348 			goto arith_done;
1349 #endif
1350 		case 10:	/* addc */
1351 			add_with_carry(regs, op, rd, regs->gpr[ra],
1352 				       regs->gpr[rb], 0);
1353 			goto arith_done;
1354 
1355 		case 11:	/* mulhwu */
1356 			asm("mulhwu %0,%1,%2" : "=r" (op->val) :
1357 			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
1358 			goto arith_done;
1359 
1360 		case 40:	/* subf */
1361 			op->val = regs->gpr[rb] - regs->gpr[ra];
1362 			goto arith_done;
1363 #ifdef __powerpc64__
1364 		case 73:	/* mulhd */
1365 			asm("mulhd %0,%1,%2" : "=r" (op->val) :
1366 			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
1367 			goto arith_done;
1368 #endif
1369 		case 75:	/* mulhw */
1370 			asm("mulhw %0,%1,%2" : "=r" (op->val) :
1371 			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
1372 			goto arith_done;
1373 
1374 		case 104:	/* neg */
1375 			op->val = -regs->gpr[ra];
1376 			goto arith_done;
1377 
1378 		case 136:	/* subfe */
1379 			add_with_carry(regs, op, rd, ~regs->gpr[ra],
1380 				       regs->gpr[rb], regs->xer & XER_CA);
1381 			goto arith_done;
1382 
1383 		case 138:	/* adde */
1384 			add_with_carry(regs, op, rd, regs->gpr[ra],
1385 				       regs->gpr[rb], regs->xer & XER_CA);
1386 			goto arith_done;
1387 
1388 		case 200:	/* subfze */
1389 			add_with_carry(regs, op, rd, ~regs->gpr[ra], 0L,
1390 				       regs->xer & XER_CA);
1391 			goto arith_done;
1392 
1393 		case 202:	/* addze */
1394 			add_with_carry(regs, op, rd, regs->gpr[ra], 0L,
1395 				       regs->xer & XER_CA);
1396 			goto arith_done;
1397 
1398 		case 232:	/* subfme */
1399 			add_with_carry(regs, op, rd, ~regs->gpr[ra], -1L,
1400 				       regs->xer & XER_CA);
1401 			goto arith_done;
1402 #ifdef __powerpc64__
1403 		case 233:	/* mulld */
1404 			op->val = regs->gpr[ra] * regs->gpr[rb];
1405 			goto arith_done;
1406 #endif
1407 		case 234:	/* addme */
1408 			add_with_carry(regs, op, rd, regs->gpr[ra], -1L,
1409 				       regs->xer & XER_CA);
1410 			goto arith_done;
1411 
1412 		case 235:	/* mullw */
1413 			op->val = (unsigned int) regs->gpr[ra] *
1414 				(unsigned int) regs->gpr[rb];
1415 			goto arith_done;
1416 
1417 		case 266:	/* add */
1418 			op->val = regs->gpr[ra] + regs->gpr[rb];
1419 			goto arith_done;
1420 #ifdef __powerpc64__
1421 		case 457:	/* divdu */
1422 			op->val = regs->gpr[ra] / regs->gpr[rb];
1423 			goto arith_done;
1424 #endif
1425 		case 459:	/* divwu */
1426 			op->val = (unsigned int) regs->gpr[ra] /
1427 				(unsigned int) regs->gpr[rb];
1428 			goto arith_done;
1429 #ifdef __powerpc64__
1430 		case 489:	/* divd */
1431 			op->val = (long int) regs->gpr[ra] /
1432 				(long int) regs->gpr[rb];
1433 			goto arith_done;
1434 #endif
1435 		case 491:	/* divw */
1436 			op->val = (int) regs->gpr[ra] /
1437 				(int) regs->gpr[rb];
1438 			goto arith_done;
1439 
1440 
1441 /*
1442  * Logical instructions
1443  */
1444 		case 15:	/* isel */
1445 			mb = (instr >> 6) & 0x1f; /* bc */
1446 			val = (regs->ccr >> (31 - mb)) & 1;
1447 			val2 = (ra) ? regs->gpr[ra] : 0;
1448 
1449 			op->val = (val) ? val2 : regs->gpr[rb];
1450 			goto compute_done;
1451 
1452 		case 26:	/* cntlzw */
1453 			op->val = __builtin_clz((unsigned int) regs->gpr[rd]);
1454 			goto logical_done;
1455 #ifdef __powerpc64__
1456 		case 58:	/* cntlzd */
1457 			op->val = __builtin_clzl(regs->gpr[rd]);
1458 			goto logical_done;
1459 #endif
1460 		case 28:	/* and */
1461 			op->val = regs->gpr[rd] & regs->gpr[rb];
1462 			goto logical_done;
1463 
1464 		case 60:	/* andc */
1465 			op->val = regs->gpr[rd] & ~regs->gpr[rb];
1466 			goto logical_done;
1467 
1468 		case 122:	/* popcntb */
1469 			do_popcnt(regs, op, regs->gpr[rd], 8);
1470 			goto logical_done;
1471 
1472 		case 124:	/* nor */
1473 			op->val = ~(regs->gpr[rd] | regs->gpr[rb]);
1474 			goto logical_done;
1475 
1476 		case 154:	/* prtyw */
1477 			do_prty(regs, op, regs->gpr[rd], 32);
1478 			goto logical_done;
1479 
1480 		case 186:	/* prtyd */
1481 			do_prty(regs, op, regs->gpr[rd], 64);
1482 			goto logical_done;
1483 #ifdef CONFIG_PPC64
1484 		case 252:	/* bpermd */
1485 			do_bpermd(regs, op, regs->gpr[rd], regs->gpr[rb]);
1486 			goto logical_done;
1487 #endif
1488 		case 284:	/* xor */
1489 			op->val = ~(regs->gpr[rd] ^ regs->gpr[rb]);
1490 			goto logical_done;
1491 
1492 		case 316:	/* xor */
1493 			op->val = regs->gpr[rd] ^ regs->gpr[rb];
1494 			goto logical_done;
1495 
1496 		case 378:	/* popcntw */
1497 			do_popcnt(regs, op, regs->gpr[rd], 32);
1498 			goto logical_done;
1499 
1500 		case 412:	/* orc */
1501 			op->val = regs->gpr[rd] | ~regs->gpr[rb];
1502 			goto logical_done;
1503 
1504 		case 444:	/* or */
1505 			op->val = regs->gpr[rd] | regs->gpr[rb];
1506 			goto logical_done;
1507 
1508 		case 476:	/* nand */
1509 			op->val = ~(regs->gpr[rd] & regs->gpr[rb]);
1510 			goto logical_done;
1511 #ifdef CONFIG_PPC64
1512 		case 506:	/* popcntd */
1513 			do_popcnt(regs, op, regs->gpr[rd], 64);
1514 			goto logical_done;
1515 #endif
1516 		case 922:	/* extsh */
1517 			op->val = (signed short) regs->gpr[rd];
1518 			goto logical_done;
1519 
1520 		case 954:	/* extsb */
1521 			op->val = (signed char) regs->gpr[rd];
1522 			goto logical_done;
1523 #ifdef __powerpc64__
1524 		case 986:	/* extsw */
1525 			op->val = (signed int) regs->gpr[rd];
1526 			goto logical_done;
1527 #endif
1528 
1529 /*
1530  * Shift instructions
1531  */
1532 		case 24:	/* slw */
1533 			sh = regs->gpr[rb] & 0x3f;
1534 			if (sh < 32)
1535 				op->val = (regs->gpr[rd] << sh) & 0xffffffffUL;
1536 			else
1537 				op->val = 0;
1538 			goto logical_done;
1539 
1540 		case 536:	/* srw */
1541 			sh = regs->gpr[rb] & 0x3f;
1542 			if (sh < 32)
1543 				op->val = (regs->gpr[rd] & 0xffffffffUL) >> sh;
1544 			else
1545 				op->val = 0;
1546 			goto logical_done;
1547 
1548 		case 792:	/* sraw */
1549 			op->type = COMPUTE + SETREG + SETXER;
1550 			sh = regs->gpr[rb] & 0x3f;
1551 			ival = (signed int) regs->gpr[rd];
1552 			op->val = ival >> (sh < 32 ? sh : 31);
1553 			op->xerval = regs->xer;
1554 			if (ival < 0 && (sh >= 32 || (ival & ((1ul << sh) - 1)) != 0))
1555 				op->xerval |= XER_CA;
1556 			else
1557 				op->xerval &= ~XER_CA;
1558 			goto logical_done;
1559 
1560 		case 824:	/* srawi */
1561 			op->type = COMPUTE + SETREG + SETXER;
1562 			sh = rb;
1563 			ival = (signed int) regs->gpr[rd];
1564 			op->val = ival >> sh;
1565 			op->xerval = regs->xer;
1566 			if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0)
1567 				op->xerval |= XER_CA;
1568 			else
1569 				op->xerval &= ~XER_CA;
1570 			goto logical_done;
1571 
1572 #ifdef __powerpc64__
1573 		case 27:	/* sld */
1574 			sh = regs->gpr[rb] & 0x7f;
1575 			if (sh < 64)
1576 				op->val = regs->gpr[rd] << sh;
1577 			else
1578 				op->val = 0;
1579 			goto logical_done;
1580 
1581 		case 539:	/* srd */
1582 			sh = regs->gpr[rb] & 0x7f;
1583 			if (sh < 64)
1584 				op->val = regs->gpr[rd] >> sh;
1585 			else
1586 				op->val = 0;
1587 			goto logical_done;
1588 
1589 		case 794:	/* srad */
1590 			op->type = COMPUTE + SETREG + SETXER;
1591 			sh = regs->gpr[rb] & 0x7f;
1592 			ival = (signed long int) regs->gpr[rd];
1593 			op->val = ival >> (sh < 64 ? sh : 63);
1594 			op->xerval = regs->xer;
1595 			if (ival < 0 && (sh >= 64 || (ival & ((1ul << sh) - 1)) != 0))
1596 				op->xerval |= XER_CA;
1597 			else
1598 				op->xerval &= ~XER_CA;
1599 			goto logical_done;
1600 
1601 		case 826:	/* sradi with sh_5 = 0 */
1602 		case 827:	/* sradi with sh_5 = 1 */
1603 			op->type = COMPUTE + SETREG + SETXER;
1604 			sh = rb | ((instr & 2) << 4);
1605 			ival = (signed long int) regs->gpr[rd];
1606 			op->val = ival >> sh;
1607 			op->xerval = regs->xer;
1608 			if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0)
1609 				op->xerval |= XER_CA;
1610 			else
1611 				op->xerval &= ~XER_CA;
1612 			goto logical_done;
1613 #endif /* __powerpc64__ */
1614 
1615 /*
1616  * Cache instructions
1617  */
1618 		case 54:	/* dcbst */
1619 			op->type = MKOP(CACHEOP, DCBST, 0);
1620 			op->ea = xform_ea(instr, regs);
1621 			return 0;
1622 
1623 		case 86:	/* dcbf */
1624 			op->type = MKOP(CACHEOP, DCBF, 0);
1625 			op->ea = xform_ea(instr, regs);
1626 			return 0;
1627 
1628 		case 246:	/* dcbtst */
1629 			op->type = MKOP(CACHEOP, DCBTST, 0);
1630 			op->ea = xform_ea(instr, regs);
1631 			op->reg = rd;
1632 			return 0;
1633 
1634 		case 278:	/* dcbt */
1635 			op->type = MKOP(CACHEOP, DCBTST, 0);
1636 			op->ea = xform_ea(instr, regs);
1637 			op->reg = rd;
1638 			return 0;
1639 
1640 		case 982:	/* icbi */
1641 			op->type = MKOP(CACHEOP, ICBI, 0);
1642 			op->ea = xform_ea(instr, regs);
1643 			return 0;
1644 		}
1645 		break;
1646 	}
1647 
1648 /*
1649  * Loads and stores.
1650  */
1651 	op->type = UNKNOWN;
1652 	op->update_reg = ra;
1653 	op->reg = rd;
1654 	op->val = regs->gpr[rd];
1655 	u = (instr >> 20) & UPDATE;
1656 	op->vsx_flags = 0;
1657 
1658 	switch (opcode) {
1659 	case 31:
1660 		u = instr & UPDATE;
1661 		op->ea = xform_ea(instr, regs);
1662 		switch ((instr >> 1) & 0x3ff) {
1663 		case 20:	/* lwarx */
1664 			op->type = MKOP(LARX, 0, 4);
1665 			break;
1666 
1667 		case 150:	/* stwcx. */
1668 			op->type = MKOP(STCX, 0, 4);
1669 			break;
1670 
1671 #ifdef __powerpc64__
1672 		case 84:	/* ldarx */
1673 			op->type = MKOP(LARX, 0, 8);
1674 			break;
1675 
1676 		case 214:	/* stdcx. */
1677 			op->type = MKOP(STCX, 0, 8);
1678 			break;
1679 
1680 		case 52:	/* lbarx */
1681 			op->type = MKOP(LARX, 0, 1);
1682 			break;
1683 
1684 		case 694:	/* stbcx. */
1685 			op->type = MKOP(STCX, 0, 1);
1686 			break;
1687 
1688 		case 116:	/* lharx */
1689 			op->type = MKOP(LARX, 0, 2);
1690 			break;
1691 
1692 		case 726:	/* sthcx. */
1693 			op->type = MKOP(STCX, 0, 2);
1694 			break;
1695 
1696 		case 276:	/* lqarx */
1697 			if (!((rd & 1) || rd == ra || rd == rb))
1698 				op->type = MKOP(LARX, 0, 16);
1699 			break;
1700 
1701 		case 182:	/* stqcx. */
1702 			if (!(rd & 1))
1703 				op->type = MKOP(STCX, 0, 16);
1704 			break;
1705 #endif
1706 
1707 		case 23:	/* lwzx */
1708 		case 55:	/* lwzux */
1709 			op->type = MKOP(LOAD, u, 4);
1710 			break;
1711 
1712 		case 87:	/* lbzx */
1713 		case 119:	/* lbzux */
1714 			op->type = MKOP(LOAD, u, 1);
1715 			break;
1716 
1717 #ifdef CONFIG_ALTIVEC
1718 		case 103:	/* lvx */
1719 		case 359:	/* lvxl */
1720 			op->type = MKOP(LOAD_VMX, 0, 16);
1721 			op->element_size = 16;
1722 			break;
1723 
1724 		case 231:	/* stvx */
1725 		case 487:	/* stvxl */
1726 			op->type = MKOP(STORE_VMX, 0, 16);
1727 			break;
1728 #endif /* CONFIG_ALTIVEC */
1729 
1730 #ifdef __powerpc64__
1731 		case 21:	/* ldx */
1732 		case 53:	/* ldux */
1733 			op->type = MKOP(LOAD, u, 8);
1734 			break;
1735 
1736 		case 149:	/* stdx */
1737 		case 181:	/* stdux */
1738 			op->type = MKOP(STORE, u, 8);
1739 			break;
1740 #endif
1741 
1742 		case 151:	/* stwx */
1743 		case 183:	/* stwux */
1744 			op->type = MKOP(STORE, u, 4);
1745 			break;
1746 
1747 		case 215:	/* stbx */
1748 		case 247:	/* stbux */
1749 			op->type = MKOP(STORE, u, 1);
1750 			break;
1751 
1752 		case 279:	/* lhzx */
1753 		case 311:	/* lhzux */
1754 			op->type = MKOP(LOAD, u, 2);
1755 			break;
1756 
1757 #ifdef __powerpc64__
1758 		case 341:	/* lwax */
1759 		case 373:	/* lwaux */
1760 			op->type = MKOP(LOAD, SIGNEXT | u, 4);
1761 			break;
1762 #endif
1763 
1764 		case 343:	/* lhax */
1765 		case 375:	/* lhaux */
1766 			op->type = MKOP(LOAD, SIGNEXT | u, 2);
1767 			break;
1768 
1769 		case 407:	/* sthx */
1770 		case 439:	/* sthux */
1771 			op->type = MKOP(STORE, u, 2);
1772 			break;
1773 
1774 #ifdef __powerpc64__
1775 		case 532:	/* ldbrx */
1776 			op->type = MKOP(LOAD, BYTEREV, 8);
1777 			break;
1778 
1779 #endif
1780 		case 533:	/* lswx */
1781 			op->type = MKOP(LOAD_MULTI, 0, regs->xer & 0x7f);
1782 			break;
1783 
1784 		case 534:	/* lwbrx */
1785 			op->type = MKOP(LOAD, BYTEREV, 4);
1786 			break;
1787 
1788 		case 597:	/* lswi */
1789 			if (rb == 0)
1790 				rb = 32;	/* # bytes to load */
1791 			op->type = MKOP(LOAD_MULTI, 0, rb);
1792 			op->ea = 0;
1793 			if (ra)
1794 				op->ea = truncate_if_32bit(regs->msr,
1795 							   regs->gpr[ra]);
1796 			break;
1797 
1798 #ifdef CONFIG_PPC_FPU
1799 		case 535:	/* lfsx */
1800 		case 567:	/* lfsux */
1801 			op->type = MKOP(LOAD_FP, u, 4);
1802 			break;
1803 
1804 		case 599:	/* lfdx */
1805 		case 631:	/* lfdux */
1806 			op->type = MKOP(LOAD_FP, u, 8);
1807 			break;
1808 
1809 		case 663:	/* stfsx */
1810 		case 695:	/* stfsux */
1811 			op->type = MKOP(STORE_FP, u, 4);
1812 			break;
1813 
1814 		case 727:	/* stfdx */
1815 		case 759:	/* stfdux */
1816 			op->type = MKOP(STORE_FP, u, 8);
1817 			break;
1818 #endif
1819 
1820 #ifdef __powerpc64__
1821 		case 660:	/* stdbrx */
1822 			op->type = MKOP(STORE, BYTEREV, 8);
1823 			op->val = byterev_8(regs->gpr[rd]);
1824 			break;
1825 
1826 #endif
1827 		case 661:	/* stswx */
1828 			op->type = MKOP(STORE_MULTI, 0, regs->xer & 0x7f);
1829 			break;
1830 
1831 		case 662:	/* stwbrx */
1832 			op->type = MKOP(STORE, BYTEREV, 4);
1833 			op->val = byterev_4(regs->gpr[rd]);
1834 			break;
1835 
1836 		case 725:
1837 			if (rb == 0)
1838 				rb = 32;	/* # bytes to store */
1839 			op->type = MKOP(STORE_MULTI, 0, rb);
1840 			op->ea = 0;
1841 			if (ra)
1842 				op->ea = truncate_if_32bit(regs->msr,
1843 							   regs->gpr[ra]);
1844 			break;
1845 
1846 		case 790:	/* lhbrx */
1847 			op->type = MKOP(LOAD, BYTEREV, 2);
1848 			break;
1849 
1850 		case 918:	/* sthbrx */
1851 			op->type = MKOP(STORE, BYTEREV, 2);
1852 			op->val = byterev_2(regs->gpr[rd]);
1853 			break;
1854 
1855 #ifdef CONFIG_VSX
1856 		case 12:	/* lxsiwzx */
1857 			op->reg = rd | ((instr & 1) << 5);
1858 			op->type = MKOP(LOAD_VSX, 0, 4);
1859 			op->element_size = 8;
1860 			break;
1861 
1862 		case 76:	/* lxsiwax */
1863 			op->reg = rd | ((instr & 1) << 5);
1864 			op->type = MKOP(LOAD_VSX, SIGNEXT, 4);
1865 			op->element_size = 8;
1866 			break;
1867 
1868 		case 140:	/* stxsiwx */
1869 			op->reg = rd | ((instr & 1) << 5);
1870 			op->type = MKOP(STORE_VSX, 0, 4);
1871 			op->element_size = 8;
1872 			break;
1873 
1874 		case 268:	/* lxvx */
1875 			op->reg = rd | ((instr & 1) << 5);
1876 			op->type = MKOP(LOAD_VSX, 0, 16);
1877 			op->element_size = 16;
1878 			op->vsx_flags = VSX_CHECK_VEC;
1879 			break;
1880 
1881 		case 269:	/* lxvl */
1882 		case 301: {	/* lxvll */
1883 			int nb;
1884 			op->reg = rd | ((instr & 1) << 5);
1885 			op->ea = ra ? regs->gpr[ra] : 0;
1886 			nb = regs->gpr[rb] & 0xff;
1887 			if (nb > 16)
1888 				nb = 16;
1889 			op->type = MKOP(LOAD_VSX, 0, nb);
1890 			op->element_size = 16;
1891 			op->vsx_flags = ((instr & 0x20) ? VSX_LDLEFT : 0) |
1892 				VSX_CHECK_VEC;
1893 			break;
1894 		}
1895 		case 332:	/* lxvdsx */
1896 			op->reg = rd | ((instr & 1) << 5);
1897 			op->type = MKOP(LOAD_VSX, 0, 8);
1898 			op->element_size = 8;
1899 			op->vsx_flags = VSX_SPLAT;
1900 			break;
1901 
1902 		case 364:	/* lxvwsx */
1903 			op->reg = rd | ((instr & 1) << 5);
1904 			op->type = MKOP(LOAD_VSX, 0, 4);
1905 			op->element_size = 4;
1906 			op->vsx_flags = VSX_SPLAT | VSX_CHECK_VEC;
1907 			break;
1908 
1909 		case 396:	/* stxvx */
1910 			op->reg = rd | ((instr & 1) << 5);
1911 			op->type = MKOP(STORE_VSX, 0, 16);
1912 			op->element_size = 16;
1913 			op->vsx_flags = VSX_CHECK_VEC;
1914 			break;
1915 
1916 		case 397:	/* stxvl */
1917 		case 429: {	/* stxvll */
1918 			int nb;
1919 			op->reg = rd | ((instr & 1) << 5);
1920 			op->ea = ra ? regs->gpr[ra] : 0;
1921 			nb = regs->gpr[rb] & 0xff;
1922 			if (nb > 16)
1923 				nb = 16;
1924 			op->type = MKOP(STORE_VSX, 0, nb);
1925 			op->element_size = 16;
1926 			op->vsx_flags = ((instr & 0x20) ? VSX_LDLEFT : 0) |
1927 				VSX_CHECK_VEC;
1928 			break;
1929 		}
1930 		case 524:	/* lxsspx */
1931 			op->reg = rd | ((instr & 1) << 5);
1932 			op->type = MKOP(LOAD_VSX, 0, 4);
1933 			op->element_size = 8;
1934 			op->vsx_flags = VSX_FPCONV;
1935 			break;
1936 
1937 		case 588:	/* lxsdx */
1938 			op->reg = rd | ((instr & 1) << 5);
1939 			op->type = MKOP(LOAD_VSX, 0, 8);
1940 			op->element_size = 8;
1941 			break;
1942 
1943 		case 652:	/* stxsspx */
1944 			op->reg = rd | ((instr & 1) << 5);
1945 			op->type = MKOP(STORE_VSX, 0, 4);
1946 			op->element_size = 8;
1947 			op->vsx_flags = VSX_FPCONV;
1948 			break;
1949 
1950 		case 716:	/* stxsdx */
1951 			op->reg = rd | ((instr & 1) << 5);
1952 			op->type = MKOP(STORE_VSX, 0, 8);
1953 			op->element_size = 8;
1954 			break;
1955 
1956 		case 780:	/* lxvw4x */
1957 			op->reg = rd | ((instr & 1) << 5);
1958 			op->type = MKOP(LOAD_VSX, 0, 16);
1959 			op->element_size = 4;
1960 			break;
1961 
1962 		case 781:	/* lxsibzx */
1963 			op->reg = rd | ((instr & 1) << 5);
1964 			op->type = MKOP(LOAD_VSX, 0, 1);
1965 			op->element_size = 8;
1966 			op->vsx_flags = VSX_CHECK_VEC;
1967 			break;
1968 
1969 		case 812:	/* lxvh8x */
1970 			op->reg = rd | ((instr & 1) << 5);
1971 			op->type = MKOP(LOAD_VSX, 0, 16);
1972 			op->element_size = 2;
1973 			op->vsx_flags = VSX_CHECK_VEC;
1974 			break;
1975 
1976 		case 813:	/* lxsihzx */
1977 			op->reg = rd | ((instr & 1) << 5);
1978 			op->type = MKOP(LOAD_VSX, 0, 2);
1979 			op->element_size = 8;
1980 			op->vsx_flags = VSX_CHECK_VEC;
1981 			break;
1982 
1983 		case 844:	/* lxvd2x */
1984 			op->reg = rd | ((instr & 1) << 5);
1985 			op->type = MKOP(LOAD_VSX, 0, 16);
1986 			op->element_size = 8;
1987 			break;
1988 
1989 		case 876:	/* lxvb16x */
1990 			op->reg = rd | ((instr & 1) << 5);
1991 			op->type = MKOP(LOAD_VSX, 0, 16);
1992 			op->element_size = 1;
1993 			op->vsx_flags = VSX_CHECK_VEC;
1994 			break;
1995 
1996 		case 908:	/* stxvw4x */
1997 			op->reg = rd | ((instr & 1) << 5);
1998 			op->type = MKOP(STORE_VSX, 0, 16);
1999 			op->element_size = 4;
2000 			break;
2001 
2002 		case 909:	/* stxsibx */
2003 			op->reg = rd | ((instr & 1) << 5);
2004 			op->type = MKOP(STORE_VSX, 0, 1);
2005 			op->element_size = 8;
2006 			op->vsx_flags = VSX_CHECK_VEC;
2007 			break;
2008 
2009 		case 940:	/* stxvh8x */
2010 			op->reg = rd | ((instr & 1) << 5);
2011 			op->type = MKOP(STORE_VSX, 0, 16);
2012 			op->element_size = 2;
2013 			op->vsx_flags = VSX_CHECK_VEC;
2014 			break;
2015 
2016 		case 941:	/* stxsihx */
2017 			op->reg = rd | ((instr & 1) << 5);
2018 			op->type = MKOP(STORE_VSX, 0, 2);
2019 			op->element_size = 8;
2020 			op->vsx_flags = VSX_CHECK_VEC;
2021 			break;
2022 
2023 		case 972:	/* stxvd2x */
2024 			op->reg = rd | ((instr & 1) << 5);
2025 			op->type = MKOP(STORE_VSX, 0, 16);
2026 			op->element_size = 8;
2027 			break;
2028 
2029 		case 1004:	/* stxvb16x */
2030 			op->reg = rd | ((instr & 1) << 5);
2031 			op->type = MKOP(STORE_VSX, 0, 16);
2032 			op->element_size = 1;
2033 			op->vsx_flags = VSX_CHECK_VEC;
2034 			break;
2035 
2036 #endif /* CONFIG_VSX */
2037 		}
2038 		break;
2039 
2040 	case 32:	/* lwz */
2041 	case 33:	/* lwzu */
2042 		op->type = MKOP(LOAD, u, 4);
2043 		op->ea = dform_ea(instr, regs);
2044 		break;
2045 
2046 	case 34:	/* lbz */
2047 	case 35:	/* lbzu */
2048 		op->type = MKOP(LOAD, u, 1);
2049 		op->ea = dform_ea(instr, regs);
2050 		break;
2051 
2052 	case 36:	/* stw */
2053 	case 37:	/* stwu */
2054 		op->type = MKOP(STORE, u, 4);
2055 		op->ea = dform_ea(instr, regs);
2056 		break;
2057 
2058 	case 38:	/* stb */
2059 	case 39:	/* stbu */
2060 		op->type = MKOP(STORE, u, 1);
2061 		op->ea = dform_ea(instr, regs);
2062 		break;
2063 
2064 	case 40:	/* lhz */
2065 	case 41:	/* lhzu */
2066 		op->type = MKOP(LOAD, u, 2);
2067 		op->ea = dform_ea(instr, regs);
2068 		break;
2069 
2070 	case 42:	/* lha */
2071 	case 43:	/* lhau */
2072 		op->type = MKOP(LOAD, SIGNEXT | u, 2);
2073 		op->ea = dform_ea(instr, regs);
2074 		break;
2075 
2076 	case 44:	/* sth */
2077 	case 45:	/* sthu */
2078 		op->type = MKOP(STORE, u, 2);
2079 		op->ea = dform_ea(instr, regs);
2080 		break;
2081 
2082 	case 46:	/* lmw */
2083 		if (ra >= rd)
2084 			break;		/* invalid form, ra in range to load */
2085 		op->type = MKOP(LOAD_MULTI, 0, 4 * (32 - rd));
2086 		op->ea = dform_ea(instr, regs);
2087 		break;
2088 
2089 	case 47:	/* stmw */
2090 		op->type = MKOP(STORE_MULTI, 0, 4 * (32 - rd));
2091 		op->ea = dform_ea(instr, regs);
2092 		break;
2093 
2094 #ifdef CONFIG_PPC_FPU
2095 	case 48:	/* lfs */
2096 	case 49:	/* lfsu */
2097 		op->type = MKOP(LOAD_FP, u, 4);
2098 		op->ea = dform_ea(instr, regs);
2099 		break;
2100 
2101 	case 50:	/* lfd */
2102 	case 51:	/* lfdu */
2103 		op->type = MKOP(LOAD_FP, u, 8);
2104 		op->ea = dform_ea(instr, regs);
2105 		break;
2106 
2107 	case 52:	/* stfs */
2108 	case 53:	/* stfsu */
2109 		op->type = MKOP(STORE_FP, u, 4);
2110 		op->ea = dform_ea(instr, regs);
2111 		break;
2112 
2113 	case 54:	/* stfd */
2114 	case 55:	/* stfdu */
2115 		op->type = MKOP(STORE_FP, u, 8);
2116 		op->ea = dform_ea(instr, regs);
2117 		break;
2118 #endif
2119 
2120 #ifdef __powerpc64__
2121 	case 56:	/* lq */
2122 		if (!((rd & 1) || (rd == ra)))
2123 			op->type = MKOP(LOAD, 0, 16);
2124 		op->ea = dqform_ea(instr, regs);
2125 		break;
2126 #endif
2127 
2128 #ifdef CONFIG_VSX
2129 	case 57:	/* lxsd, lxssp */
2130 		op->ea = dsform_ea(instr, regs);
2131 		switch (instr & 3) {
2132 		case 2:		/* lxsd */
2133 			op->reg = rd + 32;
2134 			op->type = MKOP(LOAD_VSX, 0, 8);
2135 			op->element_size = 8;
2136 			op->vsx_flags = VSX_CHECK_VEC;
2137 			break;
2138 		case 3:		/* lxssp */
2139 			op->reg = rd + 32;
2140 			op->type = MKOP(LOAD_VSX, 0, 4);
2141 			op->element_size = 8;
2142 			op->vsx_flags = VSX_FPCONV | VSX_CHECK_VEC;
2143 			break;
2144 		}
2145 		break;
2146 #endif /* CONFIG_VSX */
2147 
2148 #ifdef __powerpc64__
2149 	case 58:	/* ld[u], lwa */
2150 		op->ea = dsform_ea(instr, regs);
2151 		switch (instr & 3) {
2152 		case 0:		/* ld */
2153 			op->type = MKOP(LOAD, 0, 8);
2154 			break;
2155 		case 1:		/* ldu */
2156 			op->type = MKOP(LOAD, UPDATE, 8);
2157 			break;
2158 		case 2:		/* lwa */
2159 			op->type = MKOP(LOAD, SIGNEXT, 4);
2160 			break;
2161 		}
2162 		break;
2163 #endif
2164 
2165 #ifdef CONFIG_VSX
2166 	case 61:	/* lxv, stxsd, stxssp, stxv */
2167 		switch (instr & 7) {
2168 		case 1:		/* lxv */
2169 			op->ea = dqform_ea(instr, regs);
2170 			if (instr & 8)
2171 				op->reg = rd + 32;
2172 			op->type = MKOP(LOAD_VSX, 0, 16);
2173 			op->element_size = 16;
2174 			op->vsx_flags = VSX_CHECK_VEC;
2175 			break;
2176 
2177 		case 2:		/* stxsd with LSB of DS field = 0 */
2178 		case 6:		/* stxsd with LSB of DS field = 1 */
2179 			op->ea = dsform_ea(instr, regs);
2180 			op->reg = rd + 32;
2181 			op->type = MKOP(STORE_VSX, 0, 8);
2182 			op->element_size = 8;
2183 			op->vsx_flags = VSX_CHECK_VEC;
2184 			break;
2185 
2186 		case 3:		/* stxssp with LSB of DS field = 0 */
2187 		case 7:		/* stxssp with LSB of DS field = 1 */
2188 			op->ea = dsform_ea(instr, regs);
2189 			op->reg = rd + 32;
2190 			op->type = MKOP(STORE_VSX, 0, 4);
2191 			op->element_size = 8;
2192 			op->vsx_flags = VSX_FPCONV | VSX_CHECK_VEC;
2193 			break;
2194 
2195 		case 5:		/* stxv */
2196 			op->ea = dqform_ea(instr, regs);
2197 			if (instr & 8)
2198 				op->reg = rd + 32;
2199 			op->type = MKOP(STORE_VSX, 0, 16);
2200 			op->element_size = 16;
2201 			op->vsx_flags = VSX_CHECK_VEC;
2202 			break;
2203 		}
2204 		break;
2205 #endif /* CONFIG_VSX */
2206 
2207 #ifdef __powerpc64__
2208 	case 62:	/* std[u] */
2209 		op->ea = dsform_ea(instr, regs);
2210 		switch (instr & 3) {
2211 		case 0:		/* std */
2212 			op->type = MKOP(STORE, 0, 8);
2213 			break;
2214 		case 1:		/* stdu */
2215 			op->type = MKOP(STORE, UPDATE, 8);
2216 			break;
2217 		case 2:		/* stq */
2218 			if (!(rd & 1))
2219 				op->type = MKOP(STORE, 0, 16);
2220 			break;
2221 		}
2222 		break;
2223 #endif /* __powerpc64__ */
2224 
2225 	}
2226 	return 0;
2227 
2228  logical_done:
2229 	if (instr & 1)
2230 		set_cr0(regs, op, ra);
2231  logical_done_nocc:
2232 	op->reg = ra;
2233 	op->type |= SETREG;
2234 	return 1;
2235 
2236  arith_done:
2237 	if (instr & 1)
2238 		set_cr0(regs, op, rd);
2239  compute_done:
2240 	op->reg = rd;
2241 	op->type |= SETREG;
2242 	return 1;
2243 
2244  priv:
2245 	op->type = INTERRUPT | 0x700;
2246 	op->val = SRR1_PROGPRIV;
2247 	return 0;
2248 
2249  trap:
2250 	op->type = INTERRUPT | 0x700;
2251 	op->val = SRR1_PROGTRAP;
2252 	return 0;
2253 }
2254 EXPORT_SYMBOL_GPL(analyse_instr);
2255 NOKPROBE_SYMBOL(analyse_instr);
2256 
2257 /*
2258  * For PPC32 we always use stwu with r1 to change the stack pointer.
2259  * So this emulated store may corrupt the exception frame, now we
2260  * have to provide the exception frame trampoline, which is pushed
2261  * below the kprobed function stack. So we only update gpr[1] but
2262  * don't emulate the real store operation. We will do real store
2263  * operation safely in exception return code by checking this flag.
2264  */
2265 static nokprobe_inline int handle_stack_update(unsigned long ea, struct pt_regs *regs)
2266 {
2267 #ifdef CONFIG_PPC32
2268 	/*
2269 	 * Check if we will touch kernel stack overflow
2270 	 */
2271 	if (ea - STACK_INT_FRAME_SIZE <= current->thread.ksp_limit) {
2272 		printk(KERN_CRIT "Can't kprobe this since kernel stack would overflow.\n");
2273 		return -EINVAL;
2274 	}
2275 #endif /* CONFIG_PPC32 */
2276 	/*
2277 	 * Check if we already set since that means we'll
2278 	 * lose the previous value.
2279 	 */
2280 	WARN_ON(test_thread_flag(TIF_EMULATE_STACK_STORE));
2281 	set_thread_flag(TIF_EMULATE_STACK_STORE);
2282 	return 0;
2283 }
2284 
2285 static nokprobe_inline void do_signext(unsigned long *valp, int size)
2286 {
2287 	switch (size) {
2288 	case 2:
2289 		*valp = (signed short) *valp;
2290 		break;
2291 	case 4:
2292 		*valp = (signed int) *valp;
2293 		break;
2294 	}
2295 }
2296 
2297 static nokprobe_inline void do_byterev(unsigned long *valp, int size)
2298 {
2299 	switch (size) {
2300 	case 2:
2301 		*valp = byterev_2(*valp);
2302 		break;
2303 	case 4:
2304 		*valp = byterev_4(*valp);
2305 		break;
2306 #ifdef __powerpc64__
2307 	case 8:
2308 		*valp = byterev_8(*valp);
2309 		break;
2310 #endif
2311 	}
2312 }
2313 
2314 /*
2315  * Emulate an instruction that can be executed just by updating
2316  * fields in *regs.
2317  */
2318 void emulate_update_regs(struct pt_regs *regs, struct instruction_op *op)
2319 {
2320 	unsigned long next_pc;
2321 
2322 	next_pc = truncate_if_32bit(regs->msr, regs->nip + 4);
2323 	switch (op->type & INSTR_TYPE_MASK) {
2324 	case COMPUTE:
2325 		if (op->type & SETREG)
2326 			regs->gpr[op->reg] = op->val;
2327 		if (op->type & SETCC)
2328 			regs->ccr = op->ccval;
2329 		if (op->type & SETXER)
2330 			regs->xer = op->xerval;
2331 		break;
2332 
2333 	case BRANCH:
2334 		if (op->type & SETLK)
2335 			regs->link = next_pc;
2336 		if (op->type & BRTAKEN)
2337 			next_pc = op->val;
2338 		if (op->type & DECCTR)
2339 			--regs->ctr;
2340 		break;
2341 
2342 	case BARRIER:
2343 		switch (op->type & BARRIER_MASK) {
2344 		case BARRIER_SYNC:
2345 			mb();
2346 			break;
2347 		case BARRIER_ISYNC:
2348 			isync();
2349 			break;
2350 		case BARRIER_EIEIO:
2351 			eieio();
2352 			break;
2353 		case BARRIER_LWSYNC:
2354 			asm volatile("lwsync" : : : "memory");
2355 			break;
2356 		case BARRIER_PTESYNC:
2357 			asm volatile("ptesync" : : : "memory");
2358 			break;
2359 		}
2360 		break;
2361 
2362 	case MFSPR:
2363 		switch (op->spr) {
2364 		case SPRN_XER:
2365 			regs->gpr[op->reg] = regs->xer & 0xffffffffUL;
2366 			break;
2367 		case SPRN_LR:
2368 			regs->gpr[op->reg] = regs->link;
2369 			break;
2370 		case SPRN_CTR:
2371 			regs->gpr[op->reg] = regs->ctr;
2372 			break;
2373 		default:
2374 			WARN_ON_ONCE(1);
2375 		}
2376 		break;
2377 
2378 	case MTSPR:
2379 		switch (op->spr) {
2380 		case SPRN_XER:
2381 			regs->xer = op->val & 0xffffffffUL;
2382 			break;
2383 		case SPRN_LR:
2384 			regs->link = op->val;
2385 			break;
2386 		case SPRN_CTR:
2387 			regs->ctr = op->val;
2388 			break;
2389 		default:
2390 			WARN_ON_ONCE(1);
2391 		}
2392 		break;
2393 
2394 	default:
2395 		WARN_ON_ONCE(1);
2396 	}
2397 	regs->nip = next_pc;
2398 }
2399 
2400 /*
2401  * Emulate instructions that cause a transfer of control,
2402  * loads and stores, and a few other instructions.
2403  * Returns 1 if the step was emulated, 0 if not,
2404  * or -1 if the instruction is one that should not be stepped,
2405  * such as an rfid, or a mtmsrd that would clear MSR_RI.
2406  */
2407 int emulate_step(struct pt_regs *regs, unsigned int instr)
2408 {
2409 	struct instruction_op op;
2410 	int r, err, size;
2411 	unsigned long val;
2412 	unsigned int cr;
2413 	int i, rd, nb;
2414 
2415 	r = analyse_instr(&op, regs, instr);
2416 	if (r < 0)
2417 		return r;
2418 	if (r > 0) {
2419 		emulate_update_regs(regs, &op);
2420 		return 1;
2421 	}
2422 
2423 	err = 0;
2424 	size = GETSIZE(op.type);
2425 	switch (op.type & INSTR_TYPE_MASK) {
2426 	case CACHEOP:
2427 		if (!address_ok(regs, op.ea, 8))
2428 			return 0;
2429 		switch (op.type & CACHEOP_MASK) {
2430 		case DCBST:
2431 			__cacheop_user_asmx(op.ea, err, "dcbst");
2432 			break;
2433 		case DCBF:
2434 			__cacheop_user_asmx(op.ea, err, "dcbf");
2435 			break;
2436 		case DCBTST:
2437 			if (op.reg == 0)
2438 				prefetchw((void *) op.ea);
2439 			break;
2440 		case DCBT:
2441 			if (op.reg == 0)
2442 				prefetch((void *) op.ea);
2443 			break;
2444 		case ICBI:
2445 			__cacheop_user_asmx(op.ea, err, "icbi");
2446 			break;
2447 		}
2448 		if (err)
2449 			return 0;
2450 		goto instr_done;
2451 
2452 	case LARX:
2453 		if (op.ea & (size - 1))
2454 			break;		/* can't handle misaligned */
2455 		if (!address_ok(regs, op.ea, size))
2456 			return 0;
2457 		err = 0;
2458 		switch (size) {
2459 #ifdef __powerpc64__
2460 		case 1:
2461 			__get_user_asmx(val, op.ea, err, "lbarx");
2462 			break;
2463 		case 2:
2464 			__get_user_asmx(val, op.ea, err, "lharx");
2465 			break;
2466 #endif
2467 		case 4:
2468 			__get_user_asmx(val, op.ea, err, "lwarx");
2469 			break;
2470 #ifdef __powerpc64__
2471 		case 8:
2472 			__get_user_asmx(val, op.ea, err, "ldarx");
2473 			break;
2474 		case 16:
2475 			err = do_lqarx(op.ea, &regs->gpr[op.reg]);
2476 			goto ldst_done;
2477 #endif
2478 		default:
2479 			return 0;
2480 		}
2481 		if (!err)
2482 			regs->gpr[op.reg] = val;
2483 		goto ldst_done;
2484 
2485 	case STCX:
2486 		if (op.ea & (size - 1))
2487 			break;		/* can't handle misaligned */
2488 		if (!address_ok(regs, op.ea, size))
2489 			return 0;
2490 		err = 0;
2491 		switch (size) {
2492 #ifdef __powerpc64__
2493 		case 1:
2494 			__put_user_asmx(op.val, op.ea, err, "stbcx.", cr);
2495 			break;
2496 		case 2:
2497 			__put_user_asmx(op.val, op.ea, err, "stbcx.", cr);
2498 			break;
2499 #endif
2500 		case 4:
2501 			__put_user_asmx(op.val, op.ea, err, "stwcx.", cr);
2502 			break;
2503 #ifdef __powerpc64__
2504 		case 8:
2505 			__put_user_asmx(op.val, op.ea, err, "stdcx.", cr);
2506 			break;
2507 		case 16:
2508 			err = do_stqcx(op.ea, regs->gpr[op.reg],
2509 				       regs->gpr[op.reg + 1], &cr);
2510 			break;
2511 #endif
2512 		default:
2513 			return 0;
2514 		}
2515 		if (!err)
2516 			regs->ccr = (regs->ccr & 0x0fffffff) |
2517 				(cr & 0xe0000000) |
2518 				((regs->xer >> 3) & 0x10000000);
2519 		goto ldst_done;
2520 
2521 	case LOAD:
2522 #ifdef __powerpc64__
2523 		if (size == 16) {
2524 			err = emulate_lq(regs, op.ea, op.reg);
2525 			goto ldst_done;
2526 		}
2527 #endif
2528 		err = read_mem(&regs->gpr[op.reg], op.ea, size, regs);
2529 		if (!err) {
2530 			if (op.type & SIGNEXT)
2531 				do_signext(&regs->gpr[op.reg], size);
2532 			if (op.type & BYTEREV)
2533 				do_byterev(&regs->gpr[op.reg], size);
2534 		}
2535 		goto ldst_done;
2536 
2537 #ifdef CONFIG_PPC_FPU
2538 	case LOAD_FP:
2539 		if (!(regs->msr & MSR_FP))
2540 			return 0;
2541 		if (size == 4)
2542 			err = do_fp_load(op.reg, do_lfs, op.ea, size, regs);
2543 		else
2544 			err = do_fp_load(op.reg, do_lfd, op.ea, size, regs);
2545 		goto ldst_done;
2546 #endif
2547 #ifdef CONFIG_ALTIVEC
2548 	case LOAD_VMX:
2549 		if (!(regs->msr & MSR_VEC))
2550 			return 0;
2551 		err = do_vec_load(op.reg, do_lvx, op.ea, regs);
2552 		goto ldst_done;
2553 #endif
2554 #ifdef CONFIG_VSX
2555 	case LOAD_VSX: {
2556 		char mem[16];
2557 		union vsx_reg buf;
2558 		unsigned long msrbit = MSR_VSX;
2559 
2560 		/*
2561 		 * Some VSX instructions check the MSR_VEC bit rather than MSR_VSX
2562 		 * when the target of the instruction is a vector register.
2563 		 */
2564 		if (op.reg >= 32 && (op.vsx_flags & VSX_CHECK_VEC))
2565 			msrbit = MSR_VEC;
2566 		if (!(regs->msr & msrbit))
2567 			return 0;
2568 		if (!address_ok(regs, op.ea, size) ||
2569 		    __copy_from_user(mem, (void __user *)op.ea, size))
2570 			return 0;
2571 
2572 		emulate_vsx_load(&op, &buf, mem);
2573 		load_vsrn(op.reg, &buf);
2574 		goto ldst_done;
2575 	}
2576 #endif
2577 	case LOAD_MULTI:
2578 		if (regs->msr & MSR_LE)
2579 			return 0;
2580 		rd = op.reg;
2581 		for (i = 0; i < size; i += 4) {
2582 			nb = size - i;
2583 			if (nb > 4)
2584 				nb = 4;
2585 			err = read_mem(&regs->gpr[rd], op.ea, nb, regs);
2586 			if (err)
2587 				return 0;
2588 			if (nb < 4)	/* left-justify last bytes */
2589 				regs->gpr[rd] <<= 32 - 8 * nb;
2590 			op.ea += 4;
2591 			++rd;
2592 		}
2593 		goto instr_done;
2594 
2595 	case STORE:
2596 #ifdef __powerpc64__
2597 		if (size == 16) {
2598 			err = emulate_stq(regs, op.ea, op.reg);
2599 			goto ldst_done;
2600 		}
2601 #endif
2602 		if ((op.type & UPDATE) && size == sizeof(long) &&
2603 		    op.reg == 1 && op.update_reg == 1 &&
2604 		    !(regs->msr & MSR_PR) &&
2605 		    op.ea >= regs->gpr[1] - STACK_INT_FRAME_SIZE) {
2606 			err = handle_stack_update(op.ea, regs);
2607 			goto ldst_done;
2608 		}
2609 		err = write_mem(op.val, op.ea, size, regs);
2610 		goto ldst_done;
2611 
2612 #ifdef CONFIG_PPC_FPU
2613 	case STORE_FP:
2614 		if (!(regs->msr & MSR_FP))
2615 			return 0;
2616 		if (size == 4)
2617 			err = do_fp_store(op.reg, do_stfs, op.ea, size, regs);
2618 		else
2619 			err = do_fp_store(op.reg, do_stfd, op.ea, size, regs);
2620 		goto ldst_done;
2621 #endif
2622 #ifdef CONFIG_ALTIVEC
2623 	case STORE_VMX:
2624 		if (!(regs->msr & MSR_VEC))
2625 			return 0;
2626 		err = do_vec_store(op.reg, do_stvx, op.ea, regs);
2627 		goto ldst_done;
2628 #endif
2629 #ifdef CONFIG_VSX
2630 	case STORE_VSX: {
2631 		char mem[16];
2632 		union vsx_reg buf;
2633 		unsigned long msrbit = MSR_VSX;
2634 
2635 		/*
2636 		 * Some VSX instructions check the MSR_VEC bit rather than MSR_VSX
2637 		 * when the target of the instruction is a vector register.
2638 		 */
2639 		if (op.reg >= 32 && (op.vsx_flags & VSX_CHECK_VEC))
2640 			msrbit = MSR_VEC;
2641 		if (!(regs->msr & msrbit))
2642 			return 0;
2643 		if (!address_ok(regs, op.ea, size))
2644 			return 0;
2645 
2646 		store_vsrn(op.reg, &buf);
2647 		emulate_vsx_store(&op, &buf, mem);
2648 		if (__copy_to_user((void __user *)op.ea, mem, size))
2649 			return 0;
2650 		goto ldst_done;
2651 	}
2652 #endif
2653 	case STORE_MULTI:
2654 		if (regs->msr & MSR_LE)
2655 			return 0;
2656 		rd = op.reg;
2657 		for (i = 0; i < size; i += 4) {
2658 			val = regs->gpr[rd];
2659 			nb = size - i;
2660 			if (nb > 4)
2661 				nb = 4;
2662 			else
2663 				val >>= 32 - 8 * nb;
2664 			err = write_mem(val, op.ea, nb, regs);
2665 			if (err)
2666 				return 0;
2667 			op.ea += 4;
2668 			++rd;
2669 		}
2670 		goto instr_done;
2671 
2672 	case MFMSR:
2673 		regs->gpr[op.reg] = regs->msr & MSR_MASK;
2674 		goto instr_done;
2675 
2676 	case MTMSR:
2677 		val = regs->gpr[op.reg];
2678 		if ((val & MSR_RI) == 0)
2679 			/* can't step mtmsr[d] that would clear MSR_RI */
2680 			return -1;
2681 		/* here op.val is the mask of bits to change */
2682 		regs->msr = (regs->msr & ~op.val) | (val & op.val);
2683 		goto instr_done;
2684 
2685 #ifdef CONFIG_PPC64
2686 	case SYSCALL:	/* sc */
2687 		/*
2688 		 * N.B. this uses knowledge about how the syscall
2689 		 * entry code works.  If that is changed, this will
2690 		 * need to be changed also.
2691 		 */
2692 		if (regs->gpr[0] == 0x1ebe &&
2693 		    cpu_has_feature(CPU_FTR_REAL_LE)) {
2694 			regs->msr ^= MSR_LE;
2695 			goto instr_done;
2696 		}
2697 		regs->gpr[9] = regs->gpr[13];
2698 		regs->gpr[10] = MSR_KERNEL;
2699 		regs->gpr[11] = regs->nip + 4;
2700 		regs->gpr[12] = regs->msr & MSR_MASK;
2701 		regs->gpr[13] = (unsigned long) get_paca();
2702 		regs->nip = (unsigned long) &system_call_common;
2703 		regs->msr = MSR_KERNEL;
2704 		return 1;
2705 
2706 	case RFI:
2707 		return -1;
2708 #endif
2709 	}
2710 	return 0;
2711 
2712  ldst_done:
2713 	if (err)
2714 		return 0;
2715 	if (op.type & UPDATE)
2716 		regs->gpr[op.update_reg] = op.ea;
2717 
2718  instr_done:
2719 	regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4);
2720 	return 1;
2721 }
2722 NOKPROBE_SYMBOL(emulate_step);
2723