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v3.1
  1/*
  2 * linux/arch/m32r/kernel/ptrace.c
  3 *
  4 * Copyright (C) 2002  Hirokazu Takata, Takeo Takahashi
  5 * Copyright (C) 2004  Hirokazu Takata, Kei Sakamoto
  6 *
  7 * Original x86 implementation:
  8 *	By Ross Biro 1/23/92
  9 *	edited by Linus Torvalds
 10 *
 11 * Some code taken from sh version:
 12 *   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
 13 * Some code taken from arm version:
 14 *   Copyright (C) 2000 Russell King
 15 */
 16
 17#include <linux/kernel.h>
 18#include <linux/sched.h>
 19#include <linux/mm.h>
 20#include <linux/err.h>
 21#include <linux/smp.h>
 22#include <linux/errno.h>
 23#include <linux/ptrace.h>
 24#include <linux/user.h>
 25#include <linux/string.h>
 26#include <linux/signal.h>
 27
 28#include <asm/cacheflush.h>
 29#include <asm/io.h>
 30#include <asm/uaccess.h>
 31#include <asm/pgtable.h>
 32#include <asm/system.h>
 33#include <asm/processor.h>
 34#include <asm/mmu_context.h>
 35
 36/*
 37 * This routine will get a word off of the process kernel stack.
 38 */
 39static inline unsigned long int
 40get_stack_long(struct task_struct *task, int offset)
 41{
 42	unsigned long *stack;
 43
 44	stack = (unsigned long *)task_pt_regs(task);
 45
 46	return stack[offset];
 47}
 48
 49/*
 50 * This routine will put a word on the process kernel stack.
 51 */
 52static inline int
 53put_stack_long(struct task_struct *task, int offset, unsigned long data)
 54{
 55	unsigned long *stack;
 56
 57	stack = (unsigned long *)task_pt_regs(task);
 58	stack[offset] = data;
 59
 60	return 0;
 61}
 62
 63static int reg_offset[] = {
 64	PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
 65	PT_R8, PT_R9, PT_R10, PT_R11, PT_R12, PT_FP, PT_LR, PT_SPU,
 66};
 67
 68/*
 69 * Read the word at offset "off" into the "struct user".  We
 70 * actually access the pt_regs stored on the kernel stack.
 71 */
 72static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
 73			    unsigned long __user *data)
 74{
 75	unsigned long tmp;
 76#ifndef NO_FPU
 77	struct user * dummy = NULL;
 78#endif
 79
 80	if ((off & 3) || off > sizeof(struct user) - 3)
 81		return -EIO;
 82
 83	off >>= 2;
 84	switch (off) {
 85	case PT_EVB:
 86		__asm__ __volatile__ (
 87			"mvfc	%0, cr5 \n\t"
 88	 		: "=r" (tmp)
 89		);
 90		break;
 91	case PT_CBR: {
 92			unsigned long psw;
 93			psw = get_stack_long(tsk, PT_PSW);
 94			tmp = ((psw >> 8) & 1);
 95		}
 96		break;
 97	case PT_PSW: {
 98			unsigned long psw, bbpsw;
 99			psw = get_stack_long(tsk, PT_PSW);
100			bbpsw = get_stack_long(tsk, PT_BBPSW);
101			tmp = ((psw >> 8) & 0xff) | ((bbpsw & 0xff) << 8);
102		}
103		break;
104	case PT_PC:
105		tmp = get_stack_long(tsk, PT_BPC);
106		break;
107	case PT_BPC:
108		off = PT_BBPC;
109		/* fall through */
110	default:
111		if (off < (sizeof(struct pt_regs) >> 2))
112			tmp = get_stack_long(tsk, off);
113#ifndef NO_FPU
114		else if (off >= (long)(&dummy->fpu >> 2) &&
115			 off < (long)(&dummy->u_fpvalid >> 2)) {
116			if (!tsk_used_math(tsk)) {
117				if (off == (long)(&dummy->fpu.fpscr >> 2))
118					tmp = FPSCR_INIT;
119				else
120					tmp = 0;
121			} else
122				tmp = ((long *)(&tsk->thread.fpu >> 2))
123					[off - (long)&dummy->fpu];
124		} else if (off == (long)(&dummy->u_fpvalid >> 2))
125			tmp = !!tsk_used_math(tsk);
126#endif /* not NO_FPU */
127		else
128			tmp = 0;
129	}
130
131	return put_user(tmp, data);
132}
133
134static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
135			     unsigned long data)
136{
137	int ret = -EIO;
138#ifndef NO_FPU
139	struct user * dummy = NULL;
140#endif
141
142	if ((off & 3) || off > sizeof(struct user) - 3)
143		return -EIO;
144
145	off >>= 2;
146	switch (off) {
147	case PT_EVB:
148	case PT_BPC:
149	case PT_SPI:
150		/* We don't allow to modify evb. */
151		ret = 0;
152		break;
153	case PT_PSW:
154	case PT_CBR: {
155			/* We allow to modify only cbr in psw */
156			unsigned long psw;
157			psw = get_stack_long(tsk, PT_PSW);
158			psw = (psw & ~0x100) | ((data & 1) << 8);
159			ret = put_stack_long(tsk, PT_PSW, psw);
160		}
161		break;
162	case PT_PC:
163		off = PT_BPC;
164		data &= ~1;
165		/* fall through */
166	default:
167		if (off < (sizeof(struct pt_regs) >> 2))
168			ret = put_stack_long(tsk, off, data);
169#ifndef NO_FPU
170		else if (off >= (long)(&dummy->fpu >> 2) &&
171			 off < (long)(&dummy->u_fpvalid >> 2)) {
172			set_stopped_child_used_math(tsk);
173			((long *)&tsk->thread.fpu)
174				[off - (long)&dummy->fpu] = data;
175			ret = 0;
176		} else if (off == (long)(&dummy->u_fpvalid >> 2)) {
177			conditional_stopped_child_used_math(data, tsk);
178			ret = 0;
179		}
180#endif /* not NO_FPU */
181		break;
182	}
183
184	return ret;
185}
186
187/*
188 * Get all user integer registers.
189 */
190static int ptrace_getregs(struct task_struct *tsk, void __user *uregs)
191{
192	struct pt_regs *regs = task_pt_regs(tsk);
193
194	return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0;
195}
196
197/*
198 * Set all user integer registers.
199 */
200static int ptrace_setregs(struct task_struct *tsk, void __user *uregs)
201{
202	struct pt_regs newregs;
203	int ret;
204
205	ret = -EFAULT;
206	if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) {
207		struct pt_regs *regs = task_pt_regs(tsk);
208		*regs = newregs;
209		ret = 0;
210	}
211
212	return ret;
213}
214
215
216static inline int
217check_condition_bit(struct task_struct *child)
218{
219	return (int)((get_stack_long(child, PT_PSW) >> 8) & 1);
220}
221
222static int
223check_condition_src(unsigned long op, unsigned long regno1,
224		    unsigned long regno2, struct task_struct *child)
225{
226	unsigned long reg1, reg2;
227
228	reg2 = get_stack_long(child, reg_offset[regno2]);
229
230	switch (op) {
231	case 0x0: /* BEQ */
232		reg1 = get_stack_long(child, reg_offset[regno1]);
233		return reg1 == reg2;
234	case 0x1: /* BNE */
235		reg1 = get_stack_long(child, reg_offset[regno1]);
236		return reg1 != reg2;
237	case 0x8: /* BEQZ */
238		return reg2 == 0;
239	case 0x9: /* BNEZ */
240		return reg2 != 0;
241	case 0xa: /* BLTZ */
242		return (int)reg2 < 0;
243	case 0xb: /* BGEZ */
244		return (int)reg2 >= 0;
245	case 0xc: /* BLEZ */
246		return (int)reg2 <= 0;
247	case 0xd: /* BGTZ */
248		return (int)reg2 > 0;
249	default:
250		/* never reached */
251		return 0;
252	}
253}
254
255static void
256compute_next_pc_for_16bit_insn(unsigned long insn, unsigned long pc,
257			       unsigned long *next_pc,
258			       struct task_struct *child)
259{
260	unsigned long op, op2, op3;
261	unsigned long disp;
262	unsigned long regno;
263	int parallel = 0;
264
265	if (insn & 0x00008000)
266		parallel = 1;
267	if (pc & 3)
268		insn &= 0x7fff;	/* right slot */
269	else
270		insn >>= 16;	/* left slot */
271
272	op = (insn >> 12) & 0xf;
273	op2 = (insn >> 8) & 0xf;
274	op3 = (insn >> 4) & 0xf;
275
276	if (op == 0x7) {
277		switch (op2) {
278		case 0xd: /* BNC */
279		case 0x9: /* BNCL */
280			if (!check_condition_bit(child)) {
281				disp = (long)(insn << 24) >> 22;
282				*next_pc = (pc & ~0x3) + disp;
283				return;
284			}
285			break;
286		case 0x8: /* BCL */
287		case 0xc: /* BC */
288			if (check_condition_bit(child)) {
289				disp = (long)(insn << 24) >> 22;
290				*next_pc = (pc & ~0x3) + disp;
291				return;
292			}
293			break;
294		case 0xe: /* BL */
295		case 0xf: /* BRA */
296			disp = (long)(insn << 24) >> 22;
297			*next_pc = (pc & ~0x3) + disp;
298			return;
299			break;
300		}
301	} else if (op == 0x1) {
302		switch (op2) {
303		case 0x0:
304			if (op3 == 0xf) { /* TRAP */
305#if 1
306				/* pass through */
307#else
308 				/* kernel space is not allowed as next_pc */
309				unsigned long evb;
310				unsigned long trapno;
311				trapno = insn & 0xf;
312				__asm__ __volatile__ (
313					"mvfc %0, cr5\n"
314		 			:"=r"(evb)
315		 			:
316				);
317				*next_pc = evb + (trapno << 2);
318				return;
319#endif
320			} else if (op3 == 0xd) { /* RTE */
321				*next_pc = get_stack_long(child, PT_BPC);
322				return;
323			}
324			break;
325		case 0xc: /* JC */
326			if (op3 == 0xc && check_condition_bit(child)) {
327				regno = insn & 0xf;
328				*next_pc = get_stack_long(child,
329							  reg_offset[regno]);
330				return;
331			}
332			break;
333		case 0xd: /* JNC */
334			if (op3 == 0xc && !check_condition_bit(child)) {
335				regno = insn & 0xf;
336				*next_pc = get_stack_long(child,
337							  reg_offset[regno]);
338				return;
339			}
340			break;
341		case 0xe: /* JL */
342		case 0xf: /* JMP */
343			if (op3 == 0xc) { /* JMP */
344				regno = insn & 0xf;
345				*next_pc = get_stack_long(child,
346							  reg_offset[regno]);
347				return;
348			}
349			break;
350		}
351	}
352	if (parallel)
353		*next_pc = pc + 4;
354	else
355		*next_pc = pc + 2;
356}
357
358static void
359compute_next_pc_for_32bit_insn(unsigned long insn, unsigned long pc,
360			       unsigned long *next_pc,
361			       struct task_struct *child)
362{
363	unsigned long op;
364	unsigned long op2;
365	unsigned long disp;
366	unsigned long regno1, regno2;
367
368	op = (insn >> 28) & 0xf;
369	if (op == 0xf) { 	/* branch 24-bit relative */
370		op2 = (insn >> 24) & 0xf;
371		switch (op2) {
372		case 0xd:	/* BNC */
373		case 0x9:	/* BNCL */
374			if (!check_condition_bit(child)) {
375				disp = (long)(insn << 8) >> 6;
376				*next_pc = (pc & ~0x3) + disp;
377				return;
378			}
379			break;
380		case 0x8:	/* BCL */
381		case 0xc:	/* BC */
382			if (check_condition_bit(child)) {
383				disp = (long)(insn << 8) >> 6;
384				*next_pc = (pc & ~0x3) + disp;
385				return;
386			}
387			break;
388		case 0xe:	/* BL */
389		case 0xf:	/* BRA */
390			disp = (long)(insn << 8) >> 6;
391			*next_pc = (pc & ~0x3) + disp;
392			return;
393		}
394	} else if (op == 0xb) { /* branch 16-bit relative */
395		op2 = (insn >> 20) & 0xf;
396		switch (op2) {
397		case 0x0: /* BEQ */
398		case 0x1: /* BNE */
399		case 0x8: /* BEQZ */
400		case 0x9: /* BNEZ */
401		case 0xa: /* BLTZ */
402		case 0xb: /* BGEZ */
403		case 0xc: /* BLEZ */
404		case 0xd: /* BGTZ */
405			regno1 = ((insn >> 24) & 0xf);
406			regno2 = ((insn >> 16) & 0xf);
407			if (check_condition_src(op2, regno1, regno2, child)) {
408				disp = (long)(insn << 16) >> 14;
409				*next_pc = (pc & ~0x3) + disp;
410				return;
411			}
412			break;
413		}
414	}
415	*next_pc = pc + 4;
416}
417
418static inline void
419compute_next_pc(unsigned long insn, unsigned long pc,
420		unsigned long *next_pc, struct task_struct *child)
421{
422	if (insn & 0x80000000)
423		compute_next_pc_for_32bit_insn(insn, pc, next_pc, child);
424	else
425		compute_next_pc_for_16bit_insn(insn, pc, next_pc, child);
426}
427
428static int
429register_debug_trap(struct task_struct *child, unsigned long next_pc,
430	unsigned long next_insn, unsigned long *code)
431{
432	struct debug_trap *p = &child->thread.debug_trap;
433	unsigned long addr = next_pc & ~3;
434
435	if (p->nr_trap == MAX_TRAPS) {
436		printk("kernel BUG at %s %d: p->nr_trap = %d\n",
437					__FILE__, __LINE__, p->nr_trap);
438		return -1;
439	}
440	p->addr[p->nr_trap] = addr;
441	p->insn[p->nr_trap] = next_insn;
442	p->nr_trap++;
443	if (next_pc & 3) {
444		*code = (next_insn & 0xffff0000) | 0x10f1;
445		/* xxx --> TRAP1 */
446	} else {
447		if ((next_insn & 0x80000000) || (next_insn & 0x8000)) {
448			*code = 0x10f17000;
449			/* TRAP1 --> NOP */
450		} else {
451			*code = (next_insn & 0xffff) | 0x10f10000;
452			/* TRAP1 --> xxx */
453		}
454	}
455	return 0;
456}
457
458static int
459unregister_debug_trap(struct task_struct *child, unsigned long addr,
460		      unsigned long *code)
461{
462	struct debug_trap *p = &child->thread.debug_trap;
463        int i;
464
465	/* Search debug trap entry. */
466	for (i = 0; i < p->nr_trap; i++) {
467		if (p->addr[i] == addr)
468			break;
469	}
470	if (i >= p->nr_trap) {
471		/* The trap may be requested from debugger.
472		 * ptrace should do nothing in this case.
473		 */
474		return 0;
475	}
476
477	/* Recover original instruction code. */
478	*code = p->insn[i];
479
480	/* Shift debug trap entries. */
481	while (i < p->nr_trap - 1) {
482		p->insn[i] = p->insn[i + 1];
483		p->addr[i] = p->addr[i + 1];
484		i++;
485	}
486	p->nr_trap--;
487	return 1;
488}
489
490static void
491unregister_all_debug_traps(struct task_struct *child)
492{
493	struct debug_trap *p = &child->thread.debug_trap;
494	int i;
495
496	for (i = 0; i < p->nr_trap; i++)
497		access_process_vm(child, p->addr[i], &p->insn[i], sizeof(p->insn[i]), 1);
 
498	p->nr_trap = 0;
499}
500
501static inline void
502invalidate_cache(void)
503{
504#if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP)
505
506	_flush_cache_copyback_all();
507
508#else	/* ! CONFIG_CHIP_M32700 */
509
510	/* Invalidate cache */
511	__asm__ __volatile__ (
512                "ldi    r0, #-1					\n\t"
513                "ldi    r1, #0					\n\t"
514                "stb    r1, @r0		; cache off		\n\t"
515                ";						\n\t"
516                "ldi    r0, #-2					\n\t"
517                "ldi    r1, #1					\n\t"
518                "stb    r1, @r0		; cache invalidate	\n\t"
519                ".fillinsn					\n"
520                "0:						\n\t"
521                "ldb    r1, @r0		; invalidate check	\n\t"
522                "bnez   r1, 0b					\n\t"
523                ";						\n\t"
524                "ldi    r0, #-1					\n\t"
525                "ldi    r1, #1					\n\t"
526                "stb    r1, @r0		; cache on		\n\t"
527		: : : "r0", "r1", "memory"
528	);
529	/* FIXME: copying-back d-cache and invalidating i-cache are needed.
530	 */
531#endif	/* CONFIG_CHIP_M32700 */
532}
533
534/* Embed a debug trap (TRAP1) code */
535static int
536embed_debug_trap(struct task_struct *child, unsigned long next_pc)
537{
538	unsigned long next_insn, code;
539	unsigned long addr = next_pc & ~3;
540
541	if (access_process_vm(child, addr, &next_insn, sizeof(next_insn), 0)
 
542	    != sizeof(next_insn)) {
543		return -1; /* error */
544	}
545
546	/* Set a trap code. */
547	if (register_debug_trap(child, next_pc, next_insn, &code)) {
548		return -1; /* error */
549	}
550	if (access_process_vm(child, addr, &code, sizeof(code), 1)
 
551	    != sizeof(code)) {
552		return -1; /* error */
553	}
554	return 0; /* success */
555}
556
557void
558withdraw_debug_trap(struct pt_regs *regs)
559{
560	unsigned long addr;
561	unsigned long code;
562
563 	addr = (regs->bpc - 2) & ~3;
564	regs->bpc -= 2;
565	if (unregister_debug_trap(current, addr, &code)) {
566	    access_process_vm(current, addr, &code, sizeof(code), 1);
 
567	    invalidate_cache();
568	}
569}
570
571void
572init_debug_traps(struct task_struct *child)
573{
574	struct debug_trap *p = &child->thread.debug_trap;
575	int i;
576	p->nr_trap = 0;
577	for (i = 0; i < MAX_TRAPS; i++) {
578		p->addr[i] = 0;
579		p->insn[i] = 0;
580	}
581}
582
583void user_enable_single_step(struct task_struct *child)
584{
585	unsigned long next_pc;
586	unsigned long pc, insn;
587
588	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
589
590	/* Compute next pc.  */
591	pc = get_stack_long(child, PT_BPC);
592
593	if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0)
 
594	    != sizeof(insn))
595		return -EIO;
596
597	compute_next_pc(insn, pc, &next_pc, child);
598	if (next_pc & 0x80000000)
599		return -EIO;
600
601	if (embed_debug_trap(child, next_pc))
602		return -EIO;
603
604	invalidate_cache();
605	return 0;
606}
607
608void user_disable_single_step(struct task_struct *child)
609{
610	unregister_all_debug_traps(child);
611	invalidate_cache();
612}
613
614/*
615 * Called by kernel/ptrace.c when detaching..
616 *
617 * Make sure single step bits etc are not set.
618 */
619void ptrace_disable(struct task_struct *child)
620{
621	/* nothing to do.. */
622}
623
624long
625arch_ptrace(struct task_struct *child, long request,
626	    unsigned long addr, unsigned long data)
627{
628	int ret;
629	unsigned long __user *datap = (unsigned long __user *) data;
630
631	switch (request) {
632	/*
633	 * read word at location "addr" in the child process.
634	 */
635	case PTRACE_PEEKTEXT:
636	case PTRACE_PEEKDATA:
637		ret = generic_ptrace_peekdata(child, addr, data);
638		break;
639
640	/*
641	 * read the word at location addr in the USER area.
642	 */
643	case PTRACE_PEEKUSR:
644		ret = ptrace_read_user(child, addr, datap);
645		break;
646
647	/*
648	 * write the word at location addr.
649	 */
650	case PTRACE_POKETEXT:
651	case PTRACE_POKEDATA:
652		ret = generic_ptrace_pokedata(child, addr, data);
653		if (ret == 0 && request == PTRACE_POKETEXT)
654			invalidate_cache();
655		break;
656
657	/*
658	 * write the word at location addr in the USER area.
659	 */
660	case PTRACE_POKEUSR:
661		ret = ptrace_write_user(child, addr, data);
662		break;
663
664	case PTRACE_GETREGS:
665		ret = ptrace_getregs(child, datap);
666		break;
667
668	case PTRACE_SETREGS:
669		ret = ptrace_setregs(child, datap);
670		break;
671
672	default:
673		ret = ptrace_request(child, request, addr, data);
674		break;
675	}
676
677	return ret;
678}
679
680/* notification of system call entry/exit
681 * - triggered by current->work.syscall_trace
682 */
683void do_syscall_trace(void)
684{
685	if (!test_thread_flag(TIF_SYSCALL_TRACE))
686		return;
687	if (!(current->ptrace & PT_PTRACED))
688		return;
689	/* the 0x80 provides a way for the tracing parent to distinguish
690	   between a syscall stop and SIGTRAP delivery */
691	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
692				 ? 0x80 : 0));
693
694	/*
695	 * this isn't the same as continuing with a signal, but it will do
696	 * for normal use.  strace only continues with a signal if the
697	 * stopping signal is not SIGTRAP.  -brl
698	 */
699	if (current->exit_code) {
700		send_sig(current->exit_code, current, 1);
701		current->exit_code = 0;
702	}
703}
v4.10.11
  1/*
  2 * linux/arch/m32r/kernel/ptrace.c
  3 *
  4 * Copyright (C) 2002  Hirokazu Takata, Takeo Takahashi
  5 * Copyright (C) 2004  Hirokazu Takata, Kei Sakamoto
  6 *
  7 * Original x86 implementation:
  8 *	By Ross Biro 1/23/92
  9 *	edited by Linus Torvalds
 10 *
 11 * Some code taken from sh version:
 12 *   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
 13 * Some code taken from arm version:
 14 *   Copyright (C) 2000 Russell King
 15 */
 16
 17#include <linux/kernel.h>
 18#include <linux/sched.h>
 19#include <linux/mm.h>
 20#include <linux/err.h>
 21#include <linux/smp.h>
 22#include <linux/errno.h>
 23#include <linux/ptrace.h>
 24#include <linux/user.h>
 25#include <linux/string.h>
 26#include <linux/signal.h>
 27
 28#include <asm/cacheflush.h>
 29#include <asm/io.h>
 30#include <linux/uaccess.h>
 31#include <asm/pgtable.h>
 
 32#include <asm/processor.h>
 33#include <asm/mmu_context.h>
 34
 35/*
 36 * This routine will get a word off of the process kernel stack.
 37 */
 38static inline unsigned long int
 39get_stack_long(struct task_struct *task, int offset)
 40{
 41	unsigned long *stack;
 42
 43	stack = (unsigned long *)task_pt_regs(task);
 44
 45	return stack[offset];
 46}
 47
 48/*
 49 * This routine will put a word on the process kernel stack.
 50 */
 51static inline int
 52put_stack_long(struct task_struct *task, int offset, unsigned long data)
 53{
 54	unsigned long *stack;
 55
 56	stack = (unsigned long *)task_pt_regs(task);
 57	stack[offset] = data;
 58
 59	return 0;
 60}
 61
 62static int reg_offset[] = {
 63	PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7,
 64	PT_R8, PT_R9, PT_R10, PT_R11, PT_R12, PT_FP, PT_LR, PT_SPU,
 65};
 66
 67/*
 68 * Read the word at offset "off" into the "struct user".  We
 69 * actually access the pt_regs stored on the kernel stack.
 70 */
 71static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
 72			    unsigned long __user *data)
 73{
 74	unsigned long tmp;
 75#ifndef NO_FPU
 76	struct user * dummy = NULL;
 77#endif
 78
 79	if ((off & 3) || off > sizeof(struct user) - 3)
 80		return -EIO;
 81
 82	off >>= 2;
 83	switch (off) {
 84	case PT_EVB:
 85		__asm__ __volatile__ (
 86			"mvfc	%0, cr5 \n\t"
 87	 		: "=r" (tmp)
 88		);
 89		break;
 90	case PT_CBR: {
 91			unsigned long psw;
 92			psw = get_stack_long(tsk, PT_PSW);
 93			tmp = ((psw >> 8) & 1);
 94		}
 95		break;
 96	case PT_PSW: {
 97			unsigned long psw, bbpsw;
 98			psw = get_stack_long(tsk, PT_PSW);
 99			bbpsw = get_stack_long(tsk, PT_BBPSW);
100			tmp = ((psw >> 8) & 0xff) | ((bbpsw & 0xff) << 8);
101		}
102		break;
103	case PT_PC:
104		tmp = get_stack_long(tsk, PT_BPC);
105		break;
106	case PT_BPC:
107		off = PT_BBPC;
108		/* fall through */
109	default:
110		if (off < (sizeof(struct pt_regs) >> 2))
111			tmp = get_stack_long(tsk, off);
112#ifndef NO_FPU
113		else if (off >= (long)(&dummy->fpu >> 2) &&
114			 off < (long)(&dummy->u_fpvalid >> 2)) {
115			if (!tsk_used_math(tsk)) {
116				if (off == (long)(&dummy->fpu.fpscr >> 2))
117					tmp = FPSCR_INIT;
118				else
119					tmp = 0;
120			} else
121				tmp = ((long *)(&tsk->thread.fpu >> 2))
122					[off - (long)&dummy->fpu];
123		} else if (off == (long)(&dummy->u_fpvalid >> 2))
124			tmp = !!tsk_used_math(tsk);
125#endif /* not NO_FPU */
126		else
127			tmp = 0;
128	}
129
130	return put_user(tmp, data);
131}
132
133static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
134			     unsigned long data)
135{
136	int ret = -EIO;
137#ifndef NO_FPU
138	struct user * dummy = NULL;
139#endif
140
141	if ((off & 3) || off > sizeof(struct user) - 3)
142		return -EIO;
143
144	off >>= 2;
145	switch (off) {
146	case PT_EVB:
147	case PT_BPC:
148	case PT_SPI:
149		/* We don't allow to modify evb. */
150		ret = 0;
151		break;
152	case PT_PSW:
153	case PT_CBR: {
154			/* We allow to modify only cbr in psw */
155			unsigned long psw;
156			psw = get_stack_long(tsk, PT_PSW);
157			psw = (psw & ~0x100) | ((data & 1) << 8);
158			ret = put_stack_long(tsk, PT_PSW, psw);
159		}
160		break;
161	case PT_PC:
162		off = PT_BPC;
163		data &= ~1;
164		/* fall through */
165	default:
166		if (off < (sizeof(struct pt_regs) >> 2))
167			ret = put_stack_long(tsk, off, data);
168#ifndef NO_FPU
169		else if (off >= (long)(&dummy->fpu >> 2) &&
170			 off < (long)(&dummy->u_fpvalid >> 2)) {
171			set_stopped_child_used_math(tsk);
172			((long *)&tsk->thread.fpu)
173				[off - (long)&dummy->fpu] = data;
174			ret = 0;
175		} else if (off == (long)(&dummy->u_fpvalid >> 2)) {
176			conditional_stopped_child_used_math(data, tsk);
177			ret = 0;
178		}
179#endif /* not NO_FPU */
180		break;
181	}
182
183	return ret;
184}
185
186/*
187 * Get all user integer registers.
188 */
189static int ptrace_getregs(struct task_struct *tsk, void __user *uregs)
190{
191	struct pt_regs *regs = task_pt_regs(tsk);
192
193	return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0;
194}
195
196/*
197 * Set all user integer registers.
198 */
199static int ptrace_setregs(struct task_struct *tsk, void __user *uregs)
200{
201	struct pt_regs newregs;
202	int ret;
203
204	ret = -EFAULT;
205	if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) {
206		struct pt_regs *regs = task_pt_regs(tsk);
207		*regs = newregs;
208		ret = 0;
209	}
210
211	return ret;
212}
213
214
215static inline int
216check_condition_bit(struct task_struct *child)
217{
218	return (int)((get_stack_long(child, PT_PSW) >> 8) & 1);
219}
220
221static int
222check_condition_src(unsigned long op, unsigned long regno1,
223		    unsigned long regno2, struct task_struct *child)
224{
225	unsigned long reg1, reg2;
226
227	reg2 = get_stack_long(child, reg_offset[regno2]);
228
229	switch (op) {
230	case 0x0: /* BEQ */
231		reg1 = get_stack_long(child, reg_offset[regno1]);
232		return reg1 == reg2;
233	case 0x1: /* BNE */
234		reg1 = get_stack_long(child, reg_offset[regno1]);
235		return reg1 != reg2;
236	case 0x8: /* BEQZ */
237		return reg2 == 0;
238	case 0x9: /* BNEZ */
239		return reg2 != 0;
240	case 0xa: /* BLTZ */
241		return (int)reg2 < 0;
242	case 0xb: /* BGEZ */
243		return (int)reg2 >= 0;
244	case 0xc: /* BLEZ */
245		return (int)reg2 <= 0;
246	case 0xd: /* BGTZ */
247		return (int)reg2 > 0;
248	default:
249		/* never reached */
250		return 0;
251	}
252}
253
254static void
255compute_next_pc_for_16bit_insn(unsigned long insn, unsigned long pc,
256			       unsigned long *next_pc,
257			       struct task_struct *child)
258{
259	unsigned long op, op2, op3;
260	unsigned long disp;
261	unsigned long regno;
262	int parallel = 0;
263
264	if (insn & 0x00008000)
265		parallel = 1;
266	if (pc & 3)
267		insn &= 0x7fff;	/* right slot */
268	else
269		insn >>= 16;	/* left slot */
270
271	op = (insn >> 12) & 0xf;
272	op2 = (insn >> 8) & 0xf;
273	op3 = (insn >> 4) & 0xf;
274
275	if (op == 0x7) {
276		switch (op2) {
277		case 0xd: /* BNC */
278		case 0x9: /* BNCL */
279			if (!check_condition_bit(child)) {
280				disp = (long)(insn << 24) >> 22;
281				*next_pc = (pc & ~0x3) + disp;
282				return;
283			}
284			break;
285		case 0x8: /* BCL */
286		case 0xc: /* BC */
287			if (check_condition_bit(child)) {
288				disp = (long)(insn << 24) >> 22;
289				*next_pc = (pc & ~0x3) + disp;
290				return;
291			}
292			break;
293		case 0xe: /* BL */
294		case 0xf: /* BRA */
295			disp = (long)(insn << 24) >> 22;
296			*next_pc = (pc & ~0x3) + disp;
297			return;
298			break;
299		}
300	} else if (op == 0x1) {
301		switch (op2) {
302		case 0x0:
303			if (op3 == 0xf) { /* TRAP */
304#if 1
305				/* pass through */
306#else
307 				/* kernel space is not allowed as next_pc */
308				unsigned long evb;
309				unsigned long trapno;
310				trapno = insn & 0xf;
311				__asm__ __volatile__ (
312					"mvfc %0, cr5\n"
313		 			:"=r"(evb)
314		 			:
315				);
316				*next_pc = evb + (trapno << 2);
317				return;
318#endif
319			} else if (op3 == 0xd) { /* RTE */
320				*next_pc = get_stack_long(child, PT_BPC);
321				return;
322			}
323			break;
324		case 0xc: /* JC */
325			if (op3 == 0xc && check_condition_bit(child)) {
326				regno = insn & 0xf;
327				*next_pc = get_stack_long(child,
328							  reg_offset[regno]);
329				return;
330			}
331			break;
332		case 0xd: /* JNC */
333			if (op3 == 0xc && !check_condition_bit(child)) {
334				regno = insn & 0xf;
335				*next_pc = get_stack_long(child,
336							  reg_offset[regno]);
337				return;
338			}
339			break;
340		case 0xe: /* JL */
341		case 0xf: /* JMP */
342			if (op3 == 0xc) { /* JMP */
343				regno = insn & 0xf;
344				*next_pc = get_stack_long(child,
345							  reg_offset[regno]);
346				return;
347			}
348			break;
349		}
350	}
351	if (parallel)
352		*next_pc = pc + 4;
353	else
354		*next_pc = pc + 2;
355}
356
357static void
358compute_next_pc_for_32bit_insn(unsigned long insn, unsigned long pc,
359			       unsigned long *next_pc,
360			       struct task_struct *child)
361{
362	unsigned long op;
363	unsigned long op2;
364	unsigned long disp;
365	unsigned long regno1, regno2;
366
367	op = (insn >> 28) & 0xf;
368	if (op == 0xf) { 	/* branch 24-bit relative */
369		op2 = (insn >> 24) & 0xf;
370		switch (op2) {
371		case 0xd:	/* BNC */
372		case 0x9:	/* BNCL */
373			if (!check_condition_bit(child)) {
374				disp = (long)(insn << 8) >> 6;
375				*next_pc = (pc & ~0x3) + disp;
376				return;
377			}
378			break;
379		case 0x8:	/* BCL */
380		case 0xc:	/* BC */
381			if (check_condition_bit(child)) {
382				disp = (long)(insn << 8) >> 6;
383				*next_pc = (pc & ~0x3) + disp;
384				return;
385			}
386			break;
387		case 0xe:	/* BL */
388		case 0xf:	/* BRA */
389			disp = (long)(insn << 8) >> 6;
390			*next_pc = (pc & ~0x3) + disp;
391			return;
392		}
393	} else if (op == 0xb) { /* branch 16-bit relative */
394		op2 = (insn >> 20) & 0xf;
395		switch (op2) {
396		case 0x0: /* BEQ */
397		case 0x1: /* BNE */
398		case 0x8: /* BEQZ */
399		case 0x9: /* BNEZ */
400		case 0xa: /* BLTZ */
401		case 0xb: /* BGEZ */
402		case 0xc: /* BLEZ */
403		case 0xd: /* BGTZ */
404			regno1 = ((insn >> 24) & 0xf);
405			regno2 = ((insn >> 16) & 0xf);
406			if (check_condition_src(op2, regno1, regno2, child)) {
407				disp = (long)(insn << 16) >> 14;
408				*next_pc = (pc & ~0x3) + disp;
409				return;
410			}
411			break;
412		}
413	}
414	*next_pc = pc + 4;
415}
416
417static inline void
418compute_next_pc(unsigned long insn, unsigned long pc,
419		unsigned long *next_pc, struct task_struct *child)
420{
421	if (insn & 0x80000000)
422		compute_next_pc_for_32bit_insn(insn, pc, next_pc, child);
423	else
424		compute_next_pc_for_16bit_insn(insn, pc, next_pc, child);
425}
426
427static int
428register_debug_trap(struct task_struct *child, unsigned long next_pc,
429	unsigned long next_insn, unsigned long *code)
430{
431	struct debug_trap *p = &child->thread.debug_trap;
432	unsigned long addr = next_pc & ~3;
433
434	if (p->nr_trap == MAX_TRAPS) {
435		printk("kernel BUG at %s %d: p->nr_trap = %d\n",
436					__FILE__, __LINE__, p->nr_trap);
437		return -1;
438	}
439	p->addr[p->nr_trap] = addr;
440	p->insn[p->nr_trap] = next_insn;
441	p->nr_trap++;
442	if (next_pc & 3) {
443		*code = (next_insn & 0xffff0000) | 0x10f1;
444		/* xxx --> TRAP1 */
445	} else {
446		if ((next_insn & 0x80000000) || (next_insn & 0x8000)) {
447			*code = 0x10f17000;
448			/* TRAP1 --> NOP */
449		} else {
450			*code = (next_insn & 0xffff) | 0x10f10000;
451			/* TRAP1 --> xxx */
452		}
453	}
454	return 0;
455}
456
457static int
458unregister_debug_trap(struct task_struct *child, unsigned long addr,
459		      unsigned long *code)
460{
461	struct debug_trap *p = &child->thread.debug_trap;
462        int i;
463
464	/* Search debug trap entry. */
465	for (i = 0; i < p->nr_trap; i++) {
466		if (p->addr[i] == addr)
467			break;
468	}
469	if (i >= p->nr_trap) {
470		/* The trap may be requested from debugger.
471		 * ptrace should do nothing in this case.
472		 */
473		return 0;
474	}
475
476	/* Recover original instruction code. */
477	*code = p->insn[i];
478
479	/* Shift debug trap entries. */
480	while (i < p->nr_trap - 1) {
481		p->insn[i] = p->insn[i + 1];
482		p->addr[i] = p->addr[i + 1];
483		i++;
484	}
485	p->nr_trap--;
486	return 1;
487}
488
489static void
490unregister_all_debug_traps(struct task_struct *child)
491{
492	struct debug_trap *p = &child->thread.debug_trap;
493	int i;
494
495	for (i = 0; i < p->nr_trap; i++)
496		access_process_vm(child, p->addr[i], &p->insn[i], sizeof(p->insn[i]),
497				FOLL_FORCE | FOLL_WRITE);
498	p->nr_trap = 0;
499}
500
501static inline void
502invalidate_cache(void)
503{
504#if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP)
505
506	_flush_cache_copyback_all();
507
508#else	/* ! CONFIG_CHIP_M32700 */
509
510	/* Invalidate cache */
511	__asm__ __volatile__ (
512                "ldi    r0, #-1					\n\t"
513                "ldi    r1, #0					\n\t"
514                "stb    r1, @r0		; cache off		\n\t"
515                ";						\n\t"
516                "ldi    r0, #-2					\n\t"
517                "ldi    r1, #1					\n\t"
518                "stb    r1, @r0		; cache invalidate	\n\t"
519                ".fillinsn					\n"
520                "0:						\n\t"
521                "ldb    r1, @r0		; invalidate check	\n\t"
522                "bnez   r1, 0b					\n\t"
523                ";						\n\t"
524                "ldi    r0, #-1					\n\t"
525                "ldi    r1, #1					\n\t"
526                "stb    r1, @r0		; cache on		\n\t"
527		: : : "r0", "r1", "memory"
528	);
529	/* FIXME: copying-back d-cache and invalidating i-cache are needed.
530	 */
531#endif	/* CONFIG_CHIP_M32700 */
532}
533
534/* Embed a debug trap (TRAP1) code */
535static int
536embed_debug_trap(struct task_struct *child, unsigned long next_pc)
537{
538	unsigned long next_insn, code;
539	unsigned long addr = next_pc & ~3;
540
541	if (access_process_vm(child, addr, &next_insn, sizeof(next_insn),
542			FOLL_FORCE)
543	    != sizeof(next_insn)) {
544		return -1; /* error */
545	}
546
547	/* Set a trap code. */
548	if (register_debug_trap(child, next_pc, next_insn, &code)) {
549		return -1; /* error */
550	}
551	if (access_process_vm(child, addr, &code, sizeof(code),
552			FOLL_FORCE | FOLL_WRITE)
553	    != sizeof(code)) {
554		return -1; /* error */
555	}
556	return 0; /* success */
557}
558
559void
560withdraw_debug_trap(struct pt_regs *regs)
561{
562	unsigned long addr;
563	unsigned long code;
564
565 	addr = (regs->bpc - 2) & ~3;
566	regs->bpc -= 2;
567	if (unregister_debug_trap(current, addr, &code)) {
568	    access_process_vm(current, addr, &code, sizeof(code),
569		    FOLL_FORCE | FOLL_WRITE);
570	    invalidate_cache();
571	}
572}
573
574void
575init_debug_traps(struct task_struct *child)
576{
577	struct debug_trap *p = &child->thread.debug_trap;
578	int i;
579	p->nr_trap = 0;
580	for (i = 0; i < MAX_TRAPS; i++) {
581		p->addr[i] = 0;
582		p->insn[i] = 0;
583	}
584}
585
586void user_enable_single_step(struct task_struct *child)
587{
588	unsigned long next_pc;
589	unsigned long pc, insn;
590
591	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
592
593	/* Compute next pc.  */
594	pc = get_stack_long(child, PT_BPC);
595
596	if (access_process_vm(child, pc&~3, &insn, sizeof(insn),
597			FOLL_FORCE)
598	    != sizeof(insn))
599		return;
600
601	compute_next_pc(insn, pc, &next_pc, child);
602	if (next_pc & 0x80000000)
603		return;
604
605	if (embed_debug_trap(child, next_pc))
606		return;
607
608	invalidate_cache();
 
609}
610
611void user_disable_single_step(struct task_struct *child)
612{
613	unregister_all_debug_traps(child);
614	invalidate_cache();
615}
616
617/*
618 * Called by kernel/ptrace.c when detaching..
619 *
620 * Make sure single step bits etc are not set.
621 */
622void ptrace_disable(struct task_struct *child)
623{
624	/* nothing to do.. */
625}
626
627long
628arch_ptrace(struct task_struct *child, long request,
629	    unsigned long addr, unsigned long data)
630{
631	int ret;
632	unsigned long __user *datap = (unsigned long __user *) data;
633
634	switch (request) {
635	/*
636	 * read word at location "addr" in the child process.
637	 */
638	case PTRACE_PEEKTEXT:
639	case PTRACE_PEEKDATA:
640		ret = generic_ptrace_peekdata(child, addr, data);
641		break;
642
643	/*
644	 * read the word at location addr in the USER area.
645	 */
646	case PTRACE_PEEKUSR:
647		ret = ptrace_read_user(child, addr, datap);
648		break;
649
650	/*
651	 * write the word at location addr.
652	 */
653	case PTRACE_POKETEXT:
654	case PTRACE_POKEDATA:
655		ret = generic_ptrace_pokedata(child, addr, data);
656		if (ret == 0 && request == PTRACE_POKETEXT)
657			invalidate_cache();
658		break;
659
660	/*
661	 * write the word at location addr in the USER area.
662	 */
663	case PTRACE_POKEUSR:
664		ret = ptrace_write_user(child, addr, data);
665		break;
666
667	case PTRACE_GETREGS:
668		ret = ptrace_getregs(child, datap);
669		break;
670
671	case PTRACE_SETREGS:
672		ret = ptrace_setregs(child, datap);
673		break;
674
675	default:
676		ret = ptrace_request(child, request, addr, data);
677		break;
678	}
679
680	return ret;
681}
682
683/* notification of system call entry/exit
684 * - triggered by current->work.syscall_trace
685 */
686void do_syscall_trace(void)
687{
688	if (!test_thread_flag(TIF_SYSCALL_TRACE))
689		return;
690	if (!(current->ptrace & PT_PTRACED))
691		return;
692	/* the 0x80 provides a way for the tracing parent to distinguish
693	   between a syscall stop and SIGTRAP delivery */
694	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
695				 ? 0x80 : 0));
696
697	/*
698	 * this isn't the same as continuing with a signal, but it will do
699	 * for normal use.  strace only continues with a signal if the
700	 * stopping signal is not SIGTRAP.  -brl
701	 */
702	if (current->exit_code) {
703		send_sig(current->exit_code, current, 1);
704		current->exit_code = 0;
705	}
706}