xref: /openbmc/linux/arch/ia64/kernel/ptrace.c (revision f42b3800)
1 /*
2  * Kernel support for the ptrace() and syscall tracing interfaces.
3  *
4  * Copyright (C) 1999-2005 Hewlett-Packard Co
5  *	David Mosberger-Tang <davidm@hpl.hp.com>
6  * Copyright (C) 2006 Intel Co
7  *  2006-08-12	- IA64 Native Utrace implementation support added by
8  *	Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9  *
10  * Derived from the x86 and Alpha versions.
11  */
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/slab.h>
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/smp_lock.h>
19 #include <linux/user.h>
20 #include <linux/security.h>
21 #include <linux/audit.h>
22 #include <linux/signal.h>
23 #include <linux/regset.h>
24 #include <linux/elf.h>
25 
26 #include <asm/pgtable.h>
27 #include <asm/processor.h>
28 #include <asm/ptrace_offsets.h>
29 #include <asm/rse.h>
30 #include <asm/system.h>
31 #include <asm/uaccess.h>
32 #include <asm/unwind.h>
33 #ifdef CONFIG_PERFMON
34 #include <asm/perfmon.h>
35 #endif
36 
37 #include "entry.h"
38 
39 /*
40  * Bits in the PSR that we allow ptrace() to change:
41  *	be, up, ac, mfl, mfh (the user mask; five bits total)
42  *	db (debug breakpoint fault; one bit)
43  *	id (instruction debug fault disable; one bit)
44  *	dd (data debug fault disable; one bit)
45  *	ri (restart instruction; two bits)
46  *	is (instruction set; one bit)
47  */
48 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS	\
49 		   | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
50 
51 #define MASK(nbits)	((1UL << (nbits)) - 1)	/* mask with NBITS bits set */
52 #define PFM_MASK	MASK(38)
53 
54 #define PTRACE_DEBUG	0
55 
56 #if PTRACE_DEBUG
57 # define dprintk(format...)	printk(format)
58 # define inline
59 #else
60 # define dprintk(format...)
61 #endif
62 
63 /* Return TRUE if PT was created due to kernel-entry via a system-call.  */
64 
65 static inline int
66 in_syscall (struct pt_regs *pt)
67 {
68 	return (long) pt->cr_ifs >= 0;
69 }
70 
71 /*
72  * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
73  * bitset where bit i is set iff the NaT bit of register i is set.
74  */
75 unsigned long
76 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
77 {
78 #	define GET_BITS(first, last, unat)				\
79 	({								\
80 		unsigned long bit = ia64_unat_pos(&pt->r##first);	\
81 		unsigned long nbits = (last - first + 1);		\
82 		unsigned long mask = MASK(nbits) << first;		\
83 		unsigned long dist;					\
84 		if (bit < first)					\
85 			dist = 64 + bit - first;			\
86 		else							\
87 			dist = bit - first;				\
88 		ia64_rotr(unat, dist) & mask;				\
89 	})
90 	unsigned long val;
91 
92 	/*
93 	 * Registers that are stored consecutively in struct pt_regs
94 	 * can be handled in parallel.  If the register order in
95 	 * struct_pt_regs changes, this code MUST be updated.
96 	 */
97 	val  = GET_BITS( 1,  1, scratch_unat);
98 	val |= GET_BITS( 2,  3, scratch_unat);
99 	val |= GET_BITS(12, 13, scratch_unat);
100 	val |= GET_BITS(14, 14, scratch_unat);
101 	val |= GET_BITS(15, 15, scratch_unat);
102 	val |= GET_BITS( 8, 11, scratch_unat);
103 	val |= GET_BITS(16, 31, scratch_unat);
104 	return val;
105 
106 #	undef GET_BITS
107 }
108 
109 /*
110  * Set the NaT bits for the scratch registers according to NAT and
111  * return the resulting unat (assuming the scratch registers are
112  * stored in PT).
113  */
114 unsigned long
115 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
116 {
117 #	define PUT_BITS(first, last, nat)				\
118 	({								\
119 		unsigned long bit = ia64_unat_pos(&pt->r##first);	\
120 		unsigned long nbits = (last - first + 1);		\
121 		unsigned long mask = MASK(nbits) << first;		\
122 		long dist;						\
123 		if (bit < first)					\
124 			dist = 64 + bit - first;			\
125 		else							\
126 			dist = bit - first;				\
127 		ia64_rotl(nat & mask, dist);				\
128 	})
129 	unsigned long scratch_unat;
130 
131 	/*
132 	 * Registers that are stored consecutively in struct pt_regs
133 	 * can be handled in parallel.  If the register order in
134 	 * struct_pt_regs changes, this code MUST be updated.
135 	 */
136 	scratch_unat  = PUT_BITS( 1,  1, nat);
137 	scratch_unat |= PUT_BITS( 2,  3, nat);
138 	scratch_unat |= PUT_BITS(12, 13, nat);
139 	scratch_unat |= PUT_BITS(14, 14, nat);
140 	scratch_unat |= PUT_BITS(15, 15, nat);
141 	scratch_unat |= PUT_BITS( 8, 11, nat);
142 	scratch_unat |= PUT_BITS(16, 31, nat);
143 
144 	return scratch_unat;
145 
146 #	undef PUT_BITS
147 }
148 
149 #define IA64_MLX_TEMPLATE	0x2
150 #define IA64_MOVL_OPCODE	6
151 
152 void
153 ia64_increment_ip (struct pt_regs *regs)
154 {
155 	unsigned long w0, ri = ia64_psr(regs)->ri + 1;
156 
157 	if (ri > 2) {
158 		ri = 0;
159 		regs->cr_iip += 16;
160 	} else if (ri == 2) {
161 		get_user(w0, (char __user *) regs->cr_iip + 0);
162 		if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
163 			/*
164 			 * rfi'ing to slot 2 of an MLX bundle causes
165 			 * an illegal operation fault.  We don't want
166 			 * that to happen...
167 			 */
168 			ri = 0;
169 			regs->cr_iip += 16;
170 		}
171 	}
172 	ia64_psr(regs)->ri = ri;
173 }
174 
175 void
176 ia64_decrement_ip (struct pt_regs *regs)
177 {
178 	unsigned long w0, ri = ia64_psr(regs)->ri - 1;
179 
180 	if (ia64_psr(regs)->ri == 0) {
181 		regs->cr_iip -= 16;
182 		ri = 2;
183 		get_user(w0, (char __user *) regs->cr_iip + 0);
184 		if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
185 			/*
186 			 * rfi'ing to slot 2 of an MLX bundle causes
187 			 * an illegal operation fault.  We don't want
188 			 * that to happen...
189 			 */
190 			ri = 1;
191 		}
192 	}
193 	ia64_psr(regs)->ri = ri;
194 }
195 
196 /*
197  * This routine is used to read an rnat bits that are stored on the
198  * kernel backing store.  Since, in general, the alignment of the user
199  * and kernel are different, this is not completely trivial.  In
200  * essence, we need to construct the user RNAT based on up to two
201  * kernel RNAT values and/or the RNAT value saved in the child's
202  * pt_regs.
203  *
204  * user rbs
205  *
206  * +--------+ <-- lowest address
207  * | slot62 |
208  * +--------+
209  * |  rnat  | 0x....1f8
210  * +--------+
211  * | slot00 | \
212  * +--------+ |
213  * | slot01 | > child_regs->ar_rnat
214  * +--------+ |
215  * | slot02 | /				kernel rbs
216  * +--------+				+--------+
217  *	    <- child_regs->ar_bspstore	| slot61 | <-- krbs
218  * +- - - - +				+--------+
219  *					| slot62 |
220  * +- - - - +				+--------+
221  *					|  rnat	 |
222  * +- - - - +				+--------+
223  *   vrnat				| slot00 |
224  * +- - - - +				+--------+
225  *					=	 =
226  *					+--------+
227  *					| slot00 | \
228  *					+--------+ |
229  *					| slot01 | > child_stack->ar_rnat
230  *					+--------+ |
231  *					| slot02 | /
232  *					+--------+
233  *						  <--- child_stack->ar_bspstore
234  *
235  * The way to think of this code is as follows: bit 0 in the user rnat
236  * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
237  * value.  The kernel rnat value holding this bit is stored in
238  * variable rnat0.  rnat1 is loaded with the kernel rnat value that
239  * form the upper bits of the user rnat value.
240  *
241  * Boundary cases:
242  *
243  * o when reading the rnat "below" the first rnat slot on the kernel
244  *   backing store, rnat0/rnat1 are set to 0 and the low order bits are
245  *   merged in from pt->ar_rnat.
246  *
247  * o when reading the rnat "above" the last rnat slot on the kernel
248  *   backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
249  */
250 static unsigned long
251 get_rnat (struct task_struct *task, struct switch_stack *sw,
252 	  unsigned long *krbs, unsigned long *urnat_addr,
253 	  unsigned long *urbs_end)
254 {
255 	unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
256 	unsigned long umask = 0, mask, m;
257 	unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
258 	long num_regs, nbits;
259 	struct pt_regs *pt;
260 
261 	pt = task_pt_regs(task);
262 	kbsp = (unsigned long *) sw->ar_bspstore;
263 	ubspstore = (unsigned long *) pt->ar_bspstore;
264 
265 	if (urbs_end < urnat_addr)
266 		nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
267 	else
268 		nbits = 63;
269 	mask = MASK(nbits);
270 	/*
271 	 * First, figure out which bit number slot 0 in user-land maps
272 	 * to in the kernel rnat.  Do this by figuring out how many
273 	 * register slots we're beyond the user's backingstore and
274 	 * then computing the equivalent address in kernel space.
275 	 */
276 	num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
277 	slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
278 	shift = ia64_rse_slot_num(slot0_kaddr);
279 	rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
280 	rnat0_kaddr = rnat1_kaddr - 64;
281 
282 	if (ubspstore + 63 > urnat_addr) {
283 		/* some bits need to be merged in from pt->ar_rnat */
284 		umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
285 		urnat = (pt->ar_rnat & umask);
286 		mask &= ~umask;
287 		if (!mask)
288 			return urnat;
289 	}
290 
291 	m = mask << shift;
292 	if (rnat0_kaddr >= kbsp)
293 		rnat0 = sw->ar_rnat;
294 	else if (rnat0_kaddr > krbs)
295 		rnat0 = *rnat0_kaddr;
296 	urnat |= (rnat0 & m) >> shift;
297 
298 	m = mask >> (63 - shift);
299 	if (rnat1_kaddr >= kbsp)
300 		rnat1 = sw->ar_rnat;
301 	else if (rnat1_kaddr > krbs)
302 		rnat1 = *rnat1_kaddr;
303 	urnat |= (rnat1 & m) << (63 - shift);
304 	return urnat;
305 }
306 
307 /*
308  * The reverse of get_rnat.
309  */
310 static void
311 put_rnat (struct task_struct *task, struct switch_stack *sw,
312 	  unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
313 	  unsigned long *urbs_end)
314 {
315 	unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
316 	unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
317 	long num_regs, nbits;
318 	struct pt_regs *pt;
319 	unsigned long cfm, *urbs_kargs;
320 
321 	pt = task_pt_regs(task);
322 	kbsp = (unsigned long *) sw->ar_bspstore;
323 	ubspstore = (unsigned long *) pt->ar_bspstore;
324 
325 	urbs_kargs = urbs_end;
326 	if (in_syscall(pt)) {
327 		/*
328 		 * If entered via syscall, don't allow user to set rnat bits
329 		 * for syscall args.
330 		 */
331 		cfm = pt->cr_ifs;
332 		urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
333 	}
334 
335 	if (urbs_kargs >= urnat_addr)
336 		nbits = 63;
337 	else {
338 		if ((urnat_addr - 63) >= urbs_kargs)
339 			return;
340 		nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
341 	}
342 	mask = MASK(nbits);
343 
344 	/*
345 	 * First, figure out which bit number slot 0 in user-land maps
346 	 * to in the kernel rnat.  Do this by figuring out how many
347 	 * register slots we're beyond the user's backingstore and
348 	 * then computing the equivalent address in kernel space.
349 	 */
350 	num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
351 	slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
352 	shift = ia64_rse_slot_num(slot0_kaddr);
353 	rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
354 	rnat0_kaddr = rnat1_kaddr - 64;
355 
356 	if (ubspstore + 63 > urnat_addr) {
357 		/* some bits need to be place in pt->ar_rnat: */
358 		umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
359 		pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
360 		mask &= ~umask;
361 		if (!mask)
362 			return;
363 	}
364 	/*
365 	 * Note: Section 11.1 of the EAS guarantees that bit 63 of an
366 	 * rnat slot is ignored. so we don't have to clear it here.
367 	 */
368 	rnat0 = (urnat << shift);
369 	m = mask << shift;
370 	if (rnat0_kaddr >= kbsp)
371 		sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
372 	else if (rnat0_kaddr > krbs)
373 		*rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
374 
375 	rnat1 = (urnat >> (63 - shift));
376 	m = mask >> (63 - shift);
377 	if (rnat1_kaddr >= kbsp)
378 		sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
379 	else if (rnat1_kaddr > krbs)
380 		*rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
381 }
382 
383 static inline int
384 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
385 	       unsigned long urbs_end)
386 {
387 	unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
388 						      urbs_end);
389 	return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
390 }
391 
392 /*
393  * Read a word from the user-level backing store of task CHILD.  ADDR
394  * is the user-level address to read the word from, VAL a pointer to
395  * the return value, and USER_BSP gives the end of the user-level
396  * backing store (i.e., it's the address that would be in ar.bsp after
397  * the user executed a "cover" instruction).
398  *
399  * This routine takes care of accessing the kernel register backing
400  * store for those registers that got spilled there.  It also takes
401  * care of calculating the appropriate RNaT collection words.
402  */
403 long
404 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
405 	   unsigned long user_rbs_end, unsigned long addr, long *val)
406 {
407 	unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
408 	struct pt_regs *child_regs;
409 	size_t copied;
410 	long ret;
411 
412 	urbs_end = (long *) user_rbs_end;
413 	laddr = (unsigned long *) addr;
414 	child_regs = task_pt_regs(child);
415 	bspstore = (unsigned long *) child_regs->ar_bspstore;
416 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
417 	if (on_kernel_rbs(addr, (unsigned long) bspstore,
418 			  (unsigned long) urbs_end))
419 	{
420 		/*
421 		 * Attempt to read the RBS in an area that's actually
422 		 * on the kernel RBS => read the corresponding bits in
423 		 * the kernel RBS.
424 		 */
425 		rnat_addr = ia64_rse_rnat_addr(laddr);
426 		ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
427 
428 		if (laddr == rnat_addr) {
429 			/* return NaT collection word itself */
430 			*val = ret;
431 			return 0;
432 		}
433 
434 		if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
435 			/*
436 			 * It is implementation dependent whether the
437 			 * data portion of a NaT value gets saved on a
438 			 * st8.spill or RSE spill (e.g., see EAS 2.6,
439 			 * 4.4.4.6 Register Spill and Fill).  To get
440 			 * consistent behavior across all possible
441 			 * IA-64 implementations, we return zero in
442 			 * this case.
443 			 */
444 			*val = 0;
445 			return 0;
446 		}
447 
448 		if (laddr < urbs_end) {
449 			/*
450 			 * The desired word is on the kernel RBS and
451 			 * is not a NaT.
452 			 */
453 			regnum = ia64_rse_num_regs(bspstore, laddr);
454 			*val = *ia64_rse_skip_regs(krbs, regnum);
455 			return 0;
456 		}
457 	}
458 	copied = access_process_vm(child, addr, &ret, sizeof(ret), 0);
459 	if (copied != sizeof(ret))
460 		return -EIO;
461 	*val = ret;
462 	return 0;
463 }
464 
465 long
466 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
467 	   unsigned long user_rbs_end, unsigned long addr, long val)
468 {
469 	unsigned long *bspstore, *krbs, regnum, *laddr;
470 	unsigned long *urbs_end = (long *) user_rbs_end;
471 	struct pt_regs *child_regs;
472 
473 	laddr = (unsigned long *) addr;
474 	child_regs = task_pt_regs(child);
475 	bspstore = (unsigned long *) child_regs->ar_bspstore;
476 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
477 	if (on_kernel_rbs(addr, (unsigned long) bspstore,
478 			  (unsigned long) urbs_end))
479 	{
480 		/*
481 		 * Attempt to write the RBS in an area that's actually
482 		 * on the kernel RBS => write the corresponding bits
483 		 * in the kernel RBS.
484 		 */
485 		if (ia64_rse_is_rnat_slot(laddr))
486 			put_rnat(child, child_stack, krbs, laddr, val,
487 				 urbs_end);
488 		else {
489 			if (laddr < urbs_end) {
490 				regnum = ia64_rse_num_regs(bspstore, laddr);
491 				*ia64_rse_skip_regs(krbs, regnum) = val;
492 			}
493 		}
494 	} else if (access_process_vm(child, addr, &val, sizeof(val), 1)
495 		   != sizeof(val))
496 		return -EIO;
497 	return 0;
498 }
499 
500 /*
501  * Calculate the address of the end of the user-level register backing
502  * store.  This is the address that would have been stored in ar.bsp
503  * if the user had executed a "cover" instruction right before
504  * entering the kernel.  If CFMP is not NULL, it is used to return the
505  * "current frame mask" that was active at the time the kernel was
506  * entered.
507  */
508 unsigned long
509 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
510 		       unsigned long *cfmp)
511 {
512 	unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
513 	long ndirty;
514 
515 	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
516 	bspstore = (unsigned long *) pt->ar_bspstore;
517 	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
518 
519 	if (in_syscall(pt))
520 		ndirty += (cfm & 0x7f);
521 	else
522 		cfm &= ~(1UL << 63);	/* clear valid bit */
523 
524 	if (cfmp)
525 		*cfmp = cfm;
526 	return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
527 }
528 
529 /*
530  * Synchronize (i.e, write) the RSE backing store living in kernel
531  * space to the VM of the CHILD task.  SW and PT are the pointers to
532  * the switch_stack and pt_regs structures, respectively.
533  * USER_RBS_END is the user-level address at which the backing store
534  * ends.
535  */
536 long
537 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
538 		    unsigned long user_rbs_start, unsigned long user_rbs_end)
539 {
540 	unsigned long addr, val;
541 	long ret;
542 
543 	/* now copy word for word from kernel rbs to user rbs: */
544 	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
545 		ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
546 		if (ret < 0)
547 			return ret;
548 		if (access_process_vm(child, addr, &val, sizeof(val), 1)
549 		    != sizeof(val))
550 			return -EIO;
551 	}
552 	return 0;
553 }
554 
555 static long
556 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
557 		unsigned long user_rbs_start, unsigned long user_rbs_end)
558 {
559 	unsigned long addr, val;
560 	long ret;
561 
562 	/* now copy word for word from user rbs to kernel rbs: */
563 	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
564 		if (access_process_vm(child, addr, &val, sizeof(val), 0)
565 				!= sizeof(val))
566 			return -EIO;
567 
568 		ret = ia64_poke(child, sw, user_rbs_end, addr, val);
569 		if (ret < 0)
570 			return ret;
571 	}
572 	return 0;
573 }
574 
575 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
576 			    unsigned long, unsigned long);
577 
578 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
579 {
580 	struct pt_regs *pt;
581 	unsigned long urbs_end;
582 	syncfunc_t fn = arg;
583 
584 	if (unw_unwind_to_user(info) < 0)
585 		return;
586 	pt = task_pt_regs(info->task);
587 	urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
588 
589 	fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
590 }
591 
592 /*
593  * when a thread is stopped (ptraced), debugger might change thread's user
594  * stack (change memory directly), and we must avoid the RSE stored in kernel
595  * to override user stack (user space's RSE is newer than kernel's in the
596  * case). To workaround the issue, we copy kernel RSE to user RSE before the
597  * task is stopped, so user RSE has updated data.  we then copy user RSE to
598  * kernel after the task is resummed from traced stop and kernel will use the
599  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
600  * synchronize user RSE to kernel.
601  */
602 void ia64_ptrace_stop(void)
603 {
604 	if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
605 		return;
606 	tsk_set_notify_resume(current);
607 	unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
608 }
609 
610 /*
611  * This is called to read back the register backing store.
612  */
613 void ia64_sync_krbs(void)
614 {
615 	clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
616 	tsk_clear_notify_resume(current);
617 
618 	unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
619 }
620 
621 /*
622  * After PTRACE_ATTACH, a thread's register backing store area in user
623  * space is assumed to contain correct data whenever the thread is
624  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
625  * But if the child was already stopped for job control when we attach
626  * to it, then it might not ever get into ptrace_stop by the time we
627  * want to examine the user memory containing the RBS.
628  */
629 void
630 ptrace_attach_sync_user_rbs (struct task_struct *child)
631 {
632 	int stopped = 0;
633 	struct unw_frame_info info;
634 
635 	/*
636 	 * If the child is in TASK_STOPPED, we need to change that to
637 	 * TASK_TRACED momentarily while we operate on it.  This ensures
638 	 * that the child won't be woken up and return to user mode while
639 	 * we are doing the sync.  (It can only be woken up for SIGKILL.)
640 	 */
641 
642 	read_lock(&tasklist_lock);
643 	if (child->signal) {
644 		spin_lock_irq(&child->sighand->siglock);
645 		if (child->state == TASK_STOPPED &&
646 		    !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
647 			tsk_set_notify_resume(child);
648 
649 			child->state = TASK_TRACED;
650 			stopped = 1;
651 		}
652 		spin_unlock_irq(&child->sighand->siglock);
653 	}
654 	read_unlock(&tasklist_lock);
655 
656 	if (!stopped)
657 		return;
658 
659 	unw_init_from_blocked_task(&info, child);
660 	do_sync_rbs(&info, ia64_sync_user_rbs);
661 
662 	/*
663 	 * Now move the child back into TASK_STOPPED if it should be in a
664 	 * job control stop, so that SIGCONT can be used to wake it up.
665 	 */
666 	read_lock(&tasklist_lock);
667 	if (child->signal) {
668 		spin_lock_irq(&child->sighand->siglock);
669 		if (child->state == TASK_TRACED &&
670 		    (child->signal->flags & SIGNAL_STOP_STOPPED)) {
671 			child->state = TASK_STOPPED;
672 		}
673 		spin_unlock_irq(&child->sighand->siglock);
674 	}
675 	read_unlock(&tasklist_lock);
676 }
677 
678 static inline int
679 thread_matches (struct task_struct *thread, unsigned long addr)
680 {
681 	unsigned long thread_rbs_end;
682 	struct pt_regs *thread_regs;
683 
684 	if (ptrace_check_attach(thread, 0) < 0)
685 		/*
686 		 * If the thread is not in an attachable state, we'll
687 		 * ignore it.  The net effect is that if ADDR happens
688 		 * to overlap with the portion of the thread's
689 		 * register backing store that is currently residing
690 		 * on the thread's kernel stack, then ptrace() may end
691 		 * up accessing a stale value.  But if the thread
692 		 * isn't stopped, that's a problem anyhow, so we're
693 		 * doing as well as we can...
694 		 */
695 		return 0;
696 
697 	thread_regs = task_pt_regs(thread);
698 	thread_rbs_end = ia64_get_user_rbs_end(thread, thread_regs, NULL);
699 	if (!on_kernel_rbs(addr, thread_regs->ar_bspstore, thread_rbs_end))
700 		return 0;
701 
702 	return 1;	/* looks like we've got a winner */
703 }
704 
705 /*
706  * Write f32-f127 back to task->thread.fph if it has been modified.
707  */
708 inline void
709 ia64_flush_fph (struct task_struct *task)
710 {
711 	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
712 
713 	/*
714 	 * Prevent migrating this task while
715 	 * we're fiddling with the FPU state
716 	 */
717 	preempt_disable();
718 	if (ia64_is_local_fpu_owner(task) && psr->mfh) {
719 		psr->mfh = 0;
720 		task->thread.flags |= IA64_THREAD_FPH_VALID;
721 		ia64_save_fpu(&task->thread.fph[0]);
722 	}
723 	preempt_enable();
724 }
725 
726 /*
727  * Sync the fph state of the task so that it can be manipulated
728  * through thread.fph.  If necessary, f32-f127 are written back to
729  * thread.fph or, if the fph state hasn't been used before, thread.fph
730  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
731  * ensure that the task picks up the state from thread.fph when it
732  * executes again.
733  */
734 void
735 ia64_sync_fph (struct task_struct *task)
736 {
737 	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
738 
739 	ia64_flush_fph(task);
740 	if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
741 		task->thread.flags |= IA64_THREAD_FPH_VALID;
742 		memset(&task->thread.fph, 0, sizeof(task->thread.fph));
743 	}
744 	ia64_drop_fpu(task);
745 	psr->dfh = 1;
746 }
747 
748 /*
749  * Change the machine-state of CHILD such that it will return via the normal
750  * kernel exit-path, rather than the syscall-exit path.
751  */
752 static void
753 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
754 			unsigned long cfm)
755 {
756 	struct unw_frame_info info, prev_info;
757 	unsigned long ip, sp, pr;
758 
759 	unw_init_from_blocked_task(&info, child);
760 	while (1) {
761 		prev_info = info;
762 		if (unw_unwind(&info) < 0)
763 			return;
764 
765 		unw_get_sp(&info, &sp);
766 		if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
767 		    < IA64_PT_REGS_SIZE) {
768 			dprintk("ptrace.%s: ran off the top of the kernel "
769 				"stack\n", __func__);
770 			return;
771 		}
772 		if (unw_get_pr (&prev_info, &pr) < 0) {
773 			unw_get_rp(&prev_info, &ip);
774 			dprintk("ptrace.%s: failed to read "
775 				"predicate register (ip=0x%lx)\n",
776 				__func__, ip);
777 			return;
778 		}
779 		if (unw_is_intr_frame(&info)
780 		    && (pr & (1UL << PRED_USER_STACK)))
781 			break;
782 	}
783 
784 	/*
785 	 * Note: at the time of this call, the target task is blocked
786 	 * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
787 	 * (aka, "pLvSys") we redirect execution from
788 	 * .work_pending_syscall_end to .work_processed_kernel.
789 	 */
790 	unw_get_pr(&prev_info, &pr);
791 	pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
792 	pr |=  (1UL << PRED_NON_SYSCALL);
793 	unw_set_pr(&prev_info, pr);
794 
795 	pt->cr_ifs = (1UL << 63) | cfm;
796 	/*
797 	 * Clear the memory that is NOT written on syscall-entry to
798 	 * ensure we do not leak kernel-state to user when execution
799 	 * resumes.
800 	 */
801 	pt->r2 = 0;
802 	pt->r3 = 0;
803 	pt->r14 = 0;
804 	memset(&pt->r16, 0, 16*8);	/* clear r16-r31 */
805 	memset(&pt->f6, 0, 6*16);	/* clear f6-f11 */
806 	pt->b7 = 0;
807 	pt->ar_ccv = 0;
808 	pt->ar_csd = 0;
809 	pt->ar_ssd = 0;
810 }
811 
812 static int
813 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
814 		 struct unw_frame_info *info,
815 		 unsigned long *data, int write_access)
816 {
817 	unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
818 	char nat = 0;
819 
820 	if (write_access) {
821 		nat_bits = *data;
822 		scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
823 		if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
824 			dprintk("ptrace: failed to set ar.unat\n");
825 			return -1;
826 		}
827 		for (regnum = 4; regnum <= 7; ++regnum) {
828 			unw_get_gr(info, regnum, &dummy, &nat);
829 			unw_set_gr(info, regnum, dummy,
830 				   (nat_bits >> regnum) & 1);
831 		}
832 	} else {
833 		if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
834 			dprintk("ptrace: failed to read ar.unat\n");
835 			return -1;
836 		}
837 		nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
838 		for (regnum = 4; regnum <= 7; ++regnum) {
839 			unw_get_gr(info, regnum, &dummy, &nat);
840 			nat_bits |= (nat != 0) << regnum;
841 		}
842 		*data = nat_bits;
843 	}
844 	return 0;
845 }
846 
847 static int
848 access_uarea (struct task_struct *child, unsigned long addr,
849 	      unsigned long *data, int write_access);
850 
851 static long
852 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
853 {
854 	unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
855 	struct unw_frame_info info;
856 	struct ia64_fpreg fpval;
857 	struct switch_stack *sw;
858 	struct pt_regs *pt;
859 	long ret, retval = 0;
860 	char nat = 0;
861 	int i;
862 
863 	if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs)))
864 		return -EIO;
865 
866 	pt = task_pt_regs(child);
867 	sw = (struct switch_stack *) (child->thread.ksp + 16);
868 	unw_init_from_blocked_task(&info, child);
869 	if (unw_unwind_to_user(&info) < 0) {
870 		return -EIO;
871 	}
872 
873 	if (((unsigned long) ppr & 0x7) != 0) {
874 		dprintk("ptrace:unaligned register address %p\n", ppr);
875 		return -EIO;
876 	}
877 
878 	if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
879 	    || access_uarea(child, PT_AR_EC, &ec, 0) < 0
880 	    || access_uarea(child, PT_AR_LC, &lc, 0) < 0
881 	    || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
882 	    || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
883 	    || access_uarea(child, PT_CFM, &cfm, 0)
884 	    || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
885 		return -EIO;
886 
887 	/* control regs */
888 
889 	retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
890 	retval |= __put_user(psr, &ppr->cr_ipsr);
891 
892 	/* app regs */
893 
894 	retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
895 	retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
896 	retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
897 	retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
898 	retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
899 	retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
900 
901 	retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
902 	retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
903 	retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
904 	retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
905 	retval |= __put_user(cfm, &ppr->cfm);
906 
907 	/* gr1-gr3 */
908 
909 	retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
910 	retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
911 
912 	/* gr4-gr7 */
913 
914 	for (i = 4; i < 8; i++) {
915 		if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
916 			return -EIO;
917 		retval |= __put_user(val, &ppr->gr[i]);
918 	}
919 
920 	/* gr8-gr11 */
921 
922 	retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
923 
924 	/* gr12-gr15 */
925 
926 	retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
927 	retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
928 	retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
929 
930 	/* gr16-gr31 */
931 
932 	retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
933 
934 	/* b0 */
935 
936 	retval |= __put_user(pt->b0, &ppr->br[0]);
937 
938 	/* b1-b5 */
939 
940 	for (i = 1; i < 6; i++) {
941 		if (unw_access_br(&info, i, &val, 0) < 0)
942 			return -EIO;
943 		__put_user(val, &ppr->br[i]);
944 	}
945 
946 	/* b6-b7 */
947 
948 	retval |= __put_user(pt->b6, &ppr->br[6]);
949 	retval |= __put_user(pt->b7, &ppr->br[7]);
950 
951 	/* fr2-fr5 */
952 
953 	for (i = 2; i < 6; i++) {
954 		if (unw_get_fr(&info, i, &fpval) < 0)
955 			return -EIO;
956 		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
957 	}
958 
959 	/* fr6-fr11 */
960 
961 	retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
962 				 sizeof(struct ia64_fpreg) * 6);
963 
964 	/* fp scratch regs(12-15) */
965 
966 	retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
967 				 sizeof(struct ia64_fpreg) * 4);
968 
969 	/* fr16-fr31 */
970 
971 	for (i = 16; i < 32; i++) {
972 		if (unw_get_fr(&info, i, &fpval) < 0)
973 			return -EIO;
974 		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
975 	}
976 
977 	/* fph */
978 
979 	ia64_flush_fph(child);
980 	retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
981 				 sizeof(ppr->fr[32]) * 96);
982 
983 	/*  preds */
984 
985 	retval |= __put_user(pt->pr, &ppr->pr);
986 
987 	/* nat bits */
988 
989 	retval |= __put_user(nat_bits, &ppr->nat);
990 
991 	ret = retval ? -EIO : 0;
992 	return ret;
993 }
994 
995 static long
996 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
997 {
998 	unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
999 	struct unw_frame_info info;
1000 	struct switch_stack *sw;
1001 	struct ia64_fpreg fpval;
1002 	struct pt_regs *pt;
1003 	long ret, retval = 0;
1004 	int i;
1005 
1006 	memset(&fpval, 0, sizeof(fpval));
1007 
1008 	if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs)))
1009 		return -EIO;
1010 
1011 	pt = task_pt_regs(child);
1012 	sw = (struct switch_stack *) (child->thread.ksp + 16);
1013 	unw_init_from_blocked_task(&info, child);
1014 	if (unw_unwind_to_user(&info) < 0) {
1015 		return -EIO;
1016 	}
1017 
1018 	if (((unsigned long) ppr & 0x7) != 0) {
1019 		dprintk("ptrace:unaligned register address %p\n", ppr);
1020 		return -EIO;
1021 	}
1022 
1023 	/* control regs */
1024 
1025 	retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
1026 	retval |= __get_user(psr, &ppr->cr_ipsr);
1027 
1028 	/* app regs */
1029 
1030 	retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1031 	retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1032 	retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1033 	retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1034 	retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1035 	retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1036 
1037 	retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1038 	retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1039 	retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1040 	retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1041 	retval |= __get_user(cfm, &ppr->cfm);
1042 
1043 	/* gr1-gr3 */
1044 
1045 	retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1046 	retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1047 
1048 	/* gr4-gr7 */
1049 
1050 	for (i = 4; i < 8; i++) {
1051 		retval |= __get_user(val, &ppr->gr[i]);
1052 		/* NaT bit will be set via PT_NAT_BITS: */
1053 		if (unw_set_gr(&info, i, val, 0) < 0)
1054 			return -EIO;
1055 	}
1056 
1057 	/* gr8-gr11 */
1058 
1059 	retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1060 
1061 	/* gr12-gr15 */
1062 
1063 	retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1064 	retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1065 	retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1066 
1067 	/* gr16-gr31 */
1068 
1069 	retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1070 
1071 	/* b0 */
1072 
1073 	retval |= __get_user(pt->b0, &ppr->br[0]);
1074 
1075 	/* b1-b5 */
1076 
1077 	for (i = 1; i < 6; i++) {
1078 		retval |= __get_user(val, &ppr->br[i]);
1079 		unw_set_br(&info, i, val);
1080 	}
1081 
1082 	/* b6-b7 */
1083 
1084 	retval |= __get_user(pt->b6, &ppr->br[6]);
1085 	retval |= __get_user(pt->b7, &ppr->br[7]);
1086 
1087 	/* fr2-fr5 */
1088 
1089 	for (i = 2; i < 6; i++) {
1090 		retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1091 		if (unw_set_fr(&info, i, fpval) < 0)
1092 			return -EIO;
1093 	}
1094 
1095 	/* fr6-fr11 */
1096 
1097 	retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1098 				   sizeof(ppr->fr[6]) * 6);
1099 
1100 	/* fp scratch regs(12-15) */
1101 
1102 	retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1103 				   sizeof(ppr->fr[12]) * 4);
1104 
1105 	/* fr16-fr31 */
1106 
1107 	for (i = 16; i < 32; i++) {
1108 		retval |= __copy_from_user(&fpval, &ppr->fr[i],
1109 					   sizeof(fpval));
1110 		if (unw_set_fr(&info, i, fpval) < 0)
1111 			return -EIO;
1112 	}
1113 
1114 	/* fph */
1115 
1116 	ia64_sync_fph(child);
1117 	retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1118 				   sizeof(ppr->fr[32]) * 96);
1119 
1120 	/* preds */
1121 
1122 	retval |= __get_user(pt->pr, &ppr->pr);
1123 
1124 	/* nat bits */
1125 
1126 	retval |= __get_user(nat_bits, &ppr->nat);
1127 
1128 	retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1129 	retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1130 	retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1131 	retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1132 	retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1133 	retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1134 	retval |= access_uarea(child, PT_CFM, &cfm, 1);
1135 	retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1136 
1137 	ret = retval ? -EIO : 0;
1138 	return ret;
1139 }
1140 
1141 void
1142 user_enable_single_step (struct task_struct *child)
1143 {
1144 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1145 
1146 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1147 	child_psr->ss = 1;
1148 }
1149 
1150 void
1151 user_enable_block_step (struct task_struct *child)
1152 {
1153 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1154 
1155 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1156 	child_psr->tb = 1;
1157 }
1158 
1159 void
1160 user_disable_single_step (struct task_struct *child)
1161 {
1162 	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1163 
1164 	/* make sure the single step/taken-branch trap bits are not set: */
1165 	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1166 	child_psr->ss = 0;
1167 	child_psr->tb = 0;
1168 }
1169 
1170 /*
1171  * Called by kernel/ptrace.c when detaching..
1172  *
1173  * Make sure the single step bit is not set.
1174  */
1175 void
1176 ptrace_disable (struct task_struct *child)
1177 {
1178 	user_disable_single_step(child);
1179 }
1180 
1181 long
1182 arch_ptrace (struct task_struct *child, long request, long addr, long data)
1183 {
1184 	switch (request) {
1185 	case PTRACE_PEEKTEXT:
1186 	case PTRACE_PEEKDATA:
1187 		/* read word at location addr */
1188 		if (access_process_vm(child, addr, &data, sizeof(data), 0)
1189 		    != sizeof(data))
1190 			return -EIO;
1191 		/* ensure return value is not mistaken for error code */
1192 		force_successful_syscall_return();
1193 		return data;
1194 
1195 	/* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1196 	 * by the generic ptrace_request().
1197 	 */
1198 
1199 	case PTRACE_PEEKUSR:
1200 		/* read the word at addr in the USER area */
1201 		if (access_uarea(child, addr, &data, 0) < 0)
1202 			return -EIO;
1203 		/* ensure return value is not mistaken for error code */
1204 		force_successful_syscall_return();
1205 		return data;
1206 
1207 	case PTRACE_POKEUSR:
1208 		/* write the word at addr in the USER area */
1209 		if (access_uarea(child, addr, &data, 1) < 0)
1210 			return -EIO;
1211 		return 0;
1212 
1213 	case PTRACE_OLD_GETSIGINFO:
1214 		/* for backwards-compatibility */
1215 		return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1216 
1217 	case PTRACE_OLD_SETSIGINFO:
1218 		/* for backwards-compatibility */
1219 		return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1220 
1221 	case PTRACE_GETREGS:
1222 		return ptrace_getregs(child,
1223 				      (struct pt_all_user_regs __user *) data);
1224 
1225 	case PTRACE_SETREGS:
1226 		return ptrace_setregs(child,
1227 				      (struct pt_all_user_regs __user *) data);
1228 
1229 	default:
1230 		return ptrace_request(child, request, addr, data);
1231 	}
1232 }
1233 
1234 
1235 static void
1236 syscall_trace (void)
1237 {
1238 	/*
1239 	 * The 0x80 provides a way for the tracing parent to
1240 	 * distinguish between a syscall stop and SIGTRAP delivery.
1241 	 */
1242 	ptrace_notify(SIGTRAP
1243 		      | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));
1244 
1245 	/*
1246 	 * This isn't the same as continuing with a signal, but it
1247 	 * will do for normal use.  strace only continues with a
1248 	 * signal if the stopping signal is not SIGTRAP.  -brl
1249 	 */
1250 	if (current->exit_code) {
1251 		send_sig(current->exit_code, current, 1);
1252 		current->exit_code = 0;
1253 	}
1254 }
1255 
1256 /* "asmlinkage" so the input arguments are preserved... */
1257 
1258 asmlinkage void
1259 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1260 		     long arg4, long arg5, long arg6, long arg7,
1261 		     struct pt_regs regs)
1262 {
1263 	if (test_thread_flag(TIF_SYSCALL_TRACE)
1264 	    && (current->ptrace & PT_PTRACED))
1265 		syscall_trace();
1266 
1267 	/* copy user rbs to kernel rbs */
1268 	if (test_thread_flag(TIF_RESTORE_RSE))
1269 		ia64_sync_krbs();
1270 
1271 	if (unlikely(current->audit_context)) {
1272 		long syscall;
1273 		int arch;
1274 
1275 		if (IS_IA32_PROCESS(&regs)) {
1276 			syscall = regs.r1;
1277 			arch = AUDIT_ARCH_I386;
1278 		} else {
1279 			syscall = regs.r15;
1280 			arch = AUDIT_ARCH_IA64;
1281 		}
1282 
1283 		audit_syscall_entry(arch, syscall, arg0, arg1, arg2, arg3);
1284 	}
1285 
1286 }
1287 
1288 /* "asmlinkage" so the input arguments are preserved... */
1289 
1290 asmlinkage void
1291 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1292 		     long arg4, long arg5, long arg6, long arg7,
1293 		     struct pt_regs regs)
1294 {
1295 	if (unlikely(current->audit_context)) {
1296 		int success = AUDITSC_RESULT(regs.r10);
1297 		long result = regs.r8;
1298 
1299 		if (success != AUDITSC_SUCCESS)
1300 			result = -result;
1301 		audit_syscall_exit(success, result);
1302 	}
1303 
1304 	if ((test_thread_flag(TIF_SYSCALL_TRACE)
1305 	    || test_thread_flag(TIF_SINGLESTEP))
1306 	    && (current->ptrace & PT_PTRACED))
1307 		syscall_trace();
1308 
1309 	/* copy user rbs to kernel rbs */
1310 	if (test_thread_flag(TIF_RESTORE_RSE))
1311 		ia64_sync_krbs();
1312 }
1313 
1314 /* Utrace implementation starts here */
1315 struct regset_get {
1316 	void *kbuf;
1317 	void __user *ubuf;
1318 };
1319 
1320 struct regset_set {
1321 	const void *kbuf;
1322 	const void __user *ubuf;
1323 };
1324 
1325 struct regset_getset {
1326 	struct task_struct *target;
1327 	const struct user_regset *regset;
1328 	union {
1329 		struct regset_get get;
1330 		struct regset_set set;
1331 	} u;
1332 	unsigned int pos;
1333 	unsigned int count;
1334 	int ret;
1335 };
1336 
1337 static int
1338 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1339 		unsigned long addr, unsigned long *data, int write_access)
1340 {
1341 	struct pt_regs *pt;
1342 	unsigned long *ptr = NULL;
1343 	int ret;
1344 	char nat = 0;
1345 
1346 	pt = task_pt_regs(target);
1347 	switch (addr) {
1348 	case ELF_GR_OFFSET(1):
1349 		ptr = &pt->r1;
1350 		break;
1351 	case ELF_GR_OFFSET(2):
1352 	case ELF_GR_OFFSET(3):
1353 		ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2));
1354 		break;
1355 	case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7):
1356 		if (write_access) {
1357 			/* read NaT bit first: */
1358 			unsigned long dummy;
1359 
1360 			ret = unw_get_gr(info, addr/8, &dummy, &nat);
1361 			if (ret < 0)
1362 				return ret;
1363 		}
1364 		return unw_access_gr(info, addr/8, data, &nat, write_access);
1365 	case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11):
1366 		ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8);
1367 		break;
1368 	case ELF_GR_OFFSET(12):
1369 	case ELF_GR_OFFSET(13):
1370 		ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12);
1371 		break;
1372 	case ELF_GR_OFFSET(14):
1373 		ptr = &pt->r14;
1374 		break;
1375 	case ELF_GR_OFFSET(15):
1376 		ptr = &pt->r15;
1377 	}
1378 	if (write_access)
1379 		*ptr = *data;
1380 	else
1381 		*data = *ptr;
1382 	return 0;
1383 }
1384 
1385 static int
1386 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1387 		unsigned long addr, unsigned long *data, int write_access)
1388 {
1389 	struct pt_regs *pt;
1390 	unsigned long *ptr = NULL;
1391 
1392 	pt = task_pt_regs(target);
1393 	switch (addr) {
1394 	case ELF_BR_OFFSET(0):
1395 		ptr = &pt->b0;
1396 		break;
1397 	case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1398 		return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1399 				     data, write_access);
1400 	case ELF_BR_OFFSET(6):
1401 		ptr = &pt->b6;
1402 		break;
1403 	case ELF_BR_OFFSET(7):
1404 		ptr = &pt->b7;
1405 	}
1406 	if (write_access)
1407 		*ptr = *data;
1408 	else
1409 		*data = *ptr;
1410 	return 0;
1411 }
1412 
1413 static int
1414 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1415 		unsigned long addr, unsigned long *data, int write_access)
1416 {
1417 	struct pt_regs *pt;
1418 	unsigned long cfm, urbs_end;
1419 	unsigned long *ptr = NULL;
1420 
1421 	pt = task_pt_regs(target);
1422 	if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1423 		switch (addr) {
1424 		case ELF_AR_RSC_OFFSET:
1425 			/* force PL3 */
1426 			if (write_access)
1427 				pt->ar_rsc = *data | (3 << 2);
1428 			else
1429 				*data = pt->ar_rsc;
1430 			return 0;
1431 		case ELF_AR_BSP_OFFSET:
1432 			/*
1433 			 * By convention, we use PT_AR_BSP to refer to
1434 			 * the end of the user-level backing store.
1435 			 * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1436 			 * to get the real value of ar.bsp at the time
1437 			 * the kernel was entered.
1438 			 *
1439 			 * Furthermore, when changing the contents of
1440 			 * PT_AR_BSP (or PT_CFM) while the task is
1441 			 * blocked in a system call, convert the state
1442 			 * so that the non-system-call exit
1443 			 * path is used.  This ensures that the proper
1444 			 * state will be picked up when resuming
1445 			 * execution.  However, it *also* means that
1446 			 * once we write PT_AR_BSP/PT_CFM, it won't be
1447 			 * possible to modify the syscall arguments of
1448 			 * the pending system call any longer.  This
1449 			 * shouldn't be an issue because modifying
1450 			 * PT_AR_BSP/PT_CFM generally implies that
1451 			 * we're either abandoning the pending system
1452 			 * call or that we defer it's re-execution
1453 			 * (e.g., due to GDB doing an inferior
1454 			 * function call).
1455 			 */
1456 			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1457 			if (write_access) {
1458 				if (*data != urbs_end) {
1459 					if (in_syscall(pt))
1460 						convert_to_non_syscall(target,
1461 								       pt,
1462 								       cfm);
1463 					/*
1464 					 * Simulate user-level write
1465 					 * of ar.bsp:
1466 					 */
1467 					pt->loadrs = 0;
1468 					pt->ar_bspstore = *data;
1469 				}
1470 			} else
1471 				*data = urbs_end;
1472 			return 0;
1473 		case ELF_AR_BSPSTORE_OFFSET:
1474 			ptr = &pt->ar_bspstore;
1475 			break;
1476 		case ELF_AR_RNAT_OFFSET:
1477 			ptr = &pt->ar_rnat;
1478 			break;
1479 		case ELF_AR_CCV_OFFSET:
1480 			ptr = &pt->ar_ccv;
1481 			break;
1482 		case ELF_AR_UNAT_OFFSET:
1483 			ptr = &pt->ar_unat;
1484 			break;
1485 		case ELF_AR_FPSR_OFFSET:
1486 			ptr = &pt->ar_fpsr;
1487 			break;
1488 		case ELF_AR_PFS_OFFSET:
1489 			ptr = &pt->ar_pfs;
1490 			break;
1491 		case ELF_AR_LC_OFFSET:
1492 			return unw_access_ar(info, UNW_AR_LC, data,
1493 					     write_access);
1494 		case ELF_AR_EC_OFFSET:
1495 			return unw_access_ar(info, UNW_AR_EC, data,
1496 					     write_access);
1497 		case ELF_AR_CSD_OFFSET:
1498 			ptr = &pt->ar_csd;
1499 			break;
1500 		case ELF_AR_SSD_OFFSET:
1501 			ptr = &pt->ar_ssd;
1502 		}
1503 	} else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1504 		switch (addr) {
1505 		case ELF_CR_IIP_OFFSET:
1506 			ptr = &pt->cr_iip;
1507 			break;
1508 		case ELF_CFM_OFFSET:
1509 			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1510 			if (write_access) {
1511 				if (((cfm ^ *data) & PFM_MASK) != 0) {
1512 					if (in_syscall(pt))
1513 						convert_to_non_syscall(target,
1514 								       pt,
1515 								       cfm);
1516 					pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1517 						      | (*data & PFM_MASK));
1518 				}
1519 			} else
1520 				*data = cfm;
1521 			return 0;
1522 		case ELF_CR_IPSR_OFFSET:
1523 			if (write_access) {
1524 				unsigned long tmp = *data;
1525 				/* psr.ri==3 is a reserved value: SDM 2:25 */
1526 				if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1527 					tmp &= ~IA64_PSR_RI;
1528 				pt->cr_ipsr = ((tmp & IPSR_MASK)
1529 					       | (pt->cr_ipsr & ~IPSR_MASK));
1530 			} else
1531 				*data = (pt->cr_ipsr & IPSR_MASK);
1532 			return 0;
1533 		}
1534 	} else if (addr == ELF_NAT_OFFSET)
1535 		return access_nat_bits(target, pt, info,
1536 				       data, write_access);
1537 	else if (addr == ELF_PR_OFFSET)
1538 		ptr = &pt->pr;
1539 	else
1540 		return -1;
1541 
1542 	if (write_access)
1543 		*ptr = *data;
1544 	else
1545 		*data = *ptr;
1546 
1547 	return 0;
1548 }
1549 
1550 static int
1551 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1552 		unsigned long addr, unsigned long *data, int write_access)
1553 {
1554 	if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15))
1555 		return access_elf_gpreg(target, info, addr, data, write_access);
1556 	else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1557 		return access_elf_breg(target, info, addr, data, write_access);
1558 	else
1559 		return access_elf_areg(target, info, addr, data, write_access);
1560 }
1561 
1562 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1563 {
1564 	struct pt_regs *pt;
1565 	struct regset_getset *dst = arg;
1566 	elf_greg_t tmp[16];
1567 	unsigned int i, index, min_copy;
1568 
1569 	if (unw_unwind_to_user(info) < 0)
1570 		return;
1571 
1572 	/*
1573 	 * coredump format:
1574 	 *      r0-r31
1575 	 *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1576 	 *      predicate registers (p0-p63)
1577 	 *      b0-b7
1578 	 *      ip cfm user-mask
1579 	 *      ar.rsc ar.bsp ar.bspstore ar.rnat
1580 	 *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1581 	 */
1582 
1583 
1584 	/* Skip r0 */
1585 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1586 		dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1587 						      &dst->u.get.kbuf,
1588 						      &dst->u.get.ubuf,
1589 						      0, ELF_GR_OFFSET(1));
1590 		if (dst->ret || dst->count == 0)
1591 			return;
1592 	}
1593 
1594 	/* gr1 - gr15 */
1595 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1596 		index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1597 		min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
1598 			 (dst->pos + dst->count) : ELF_GR_OFFSET(16);
1599 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1600 				index++)
1601 			if (access_elf_reg(dst->target, info, i,
1602 						&tmp[index], 0) < 0) {
1603 				dst->ret = -EIO;
1604 				return;
1605 			}
1606 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1607 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1608 				ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1609 		if (dst->ret || dst->count == 0)
1610 			return;
1611 	}
1612 
1613 	/* r16-r31 */
1614 	if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1615 		pt = task_pt_regs(dst->target);
1616 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1617 				&dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
1618 				ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1619 		if (dst->ret || dst->count == 0)
1620 			return;
1621 	}
1622 
1623 	/* nat, pr, b0 - b7 */
1624 	if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1625 		index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1626 		min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
1627 			 (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
1628 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1629 				index++)
1630 			if (access_elf_reg(dst->target, info, i,
1631 						&tmp[index], 0) < 0) {
1632 				dst->ret = -EIO;
1633 				return;
1634 			}
1635 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1636 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1637 				ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1638 		if (dst->ret || dst->count == 0)
1639 			return;
1640 	}
1641 
1642 	/* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1643 	 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1644 	 */
1645 	if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1646 		index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1647 		min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
1648 			 (dst->pos + dst->count) : ELF_AR_END_OFFSET;
1649 		for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1650 				index++)
1651 			if (access_elf_reg(dst->target, info, i,
1652 						&tmp[index], 0) < 0) {
1653 				dst->ret = -EIO;
1654 				return;
1655 			}
1656 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1657 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1658 				ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1659 	}
1660 }
1661 
1662 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1663 {
1664 	struct pt_regs *pt;
1665 	struct regset_getset *dst = arg;
1666 	elf_greg_t tmp[16];
1667 	unsigned int i, index;
1668 
1669 	if (unw_unwind_to_user(info) < 0)
1670 		return;
1671 
1672 	/* Skip r0 */
1673 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1674 		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1675 						       &dst->u.set.kbuf,
1676 						       &dst->u.set.ubuf,
1677 						       0, ELF_GR_OFFSET(1));
1678 		if (dst->ret || dst->count == 0)
1679 			return;
1680 	}
1681 
1682 	/* gr1-gr15 */
1683 	if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1684 		i = dst->pos;
1685 		index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1686 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1687 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1688 				ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1689 		if (dst->ret)
1690 			return;
1691 		for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1692 			if (access_elf_reg(dst->target, info, i,
1693 						&tmp[index], 1) < 0) {
1694 				dst->ret = -EIO;
1695 				return;
1696 			}
1697 		if (dst->count == 0)
1698 			return;
1699 	}
1700 
1701 	/* gr16-gr31 */
1702 	if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1703 		pt = task_pt_regs(dst->target);
1704 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1705 				&dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
1706 				ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1707 		if (dst->ret || dst->count == 0)
1708 			return;
1709 	}
1710 
1711 	/* nat, pr, b0 - b7 */
1712 	if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1713 		i = dst->pos;
1714 		index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1715 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1716 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1717 				ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1718 		if (dst->ret)
1719 			return;
1720 		for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
1721 			if (access_elf_reg(dst->target, info, i,
1722 						&tmp[index], 1) < 0) {
1723 				dst->ret = -EIO;
1724 				return;
1725 			}
1726 		if (dst->count == 0)
1727 			return;
1728 	}
1729 
1730 	/* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1731 	 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1732 	 */
1733 	if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1734 		i = dst->pos;
1735 		index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1736 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1737 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1738 				ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1739 		if (dst->ret)
1740 			return;
1741 		for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1742 			if (access_elf_reg(dst->target, info, i,
1743 						&tmp[index], 1) < 0) {
1744 				dst->ret = -EIO;
1745 				return;
1746 			}
1747 	}
1748 }
1749 
1750 #define ELF_FP_OFFSET(i)	(i * sizeof(elf_fpreg_t))
1751 
1752 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1753 {
1754 	struct regset_getset *dst = arg;
1755 	struct task_struct *task = dst->target;
1756 	elf_fpreg_t tmp[30];
1757 	int index, min_copy, i;
1758 
1759 	if (unw_unwind_to_user(info) < 0)
1760 		return;
1761 
1762 	/* Skip pos 0 and 1 */
1763 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1764 		dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1765 						      &dst->u.get.kbuf,
1766 						      &dst->u.get.ubuf,
1767 						      0, ELF_FP_OFFSET(2));
1768 		if (dst->count == 0 || dst->ret)
1769 			return;
1770 	}
1771 
1772 	/* fr2-fr31 */
1773 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1774 		index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t);
1775 
1776 		min_copy = min(((unsigned int)ELF_FP_OFFSET(32)),
1777 				dst->pos + dst->count);
1778 		for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t),
1779 				index++)
1780 			if (unw_get_fr(info, i / sizeof(elf_fpreg_t),
1781 					 &tmp[index])) {
1782 				dst->ret = -EIO;
1783 				return;
1784 			}
1785 		dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1786 				&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1787 				ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1788 		if (dst->count == 0 || dst->ret)
1789 			return;
1790 	}
1791 
1792 	/* fph */
1793 	if (dst->count > 0) {
1794 		ia64_flush_fph(dst->target);
1795 		if (task->thread.flags & IA64_THREAD_FPH_VALID)
1796 			dst->ret = user_regset_copyout(
1797 				&dst->pos, &dst->count,
1798 				&dst->u.get.kbuf, &dst->u.get.ubuf,
1799 				&dst->target->thread.fph,
1800 				ELF_FP_OFFSET(32), -1);
1801 		else
1802 			/* Zero fill instead.  */
1803 			dst->ret = user_regset_copyout_zero(
1804 				&dst->pos, &dst->count,
1805 				&dst->u.get.kbuf, &dst->u.get.ubuf,
1806 				ELF_FP_OFFSET(32), -1);
1807 	}
1808 }
1809 
1810 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1811 {
1812 	struct regset_getset *dst = arg;
1813 	elf_fpreg_t fpreg, tmp[30];
1814 	int index, start, end;
1815 
1816 	if (unw_unwind_to_user(info) < 0)
1817 		return;
1818 
1819 	/* Skip pos 0 and 1 */
1820 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1821 		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1822 						       &dst->u.set.kbuf,
1823 						       &dst->u.set.ubuf,
1824 						       0, ELF_FP_OFFSET(2));
1825 		if (dst->count == 0 || dst->ret)
1826 			return;
1827 	}
1828 
1829 	/* fr2-fr31 */
1830 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1831 		start = dst->pos;
1832 		end = min(((unsigned int)ELF_FP_OFFSET(32)),
1833 			 dst->pos + dst->count);
1834 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1835 				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1836 				ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1837 		if (dst->ret)
1838 			return;
1839 
1840 		if (start & 0xF) { /* only write high part */
1841 			if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1842 					 &fpreg)) {
1843 				dst->ret = -EIO;
1844 				return;
1845 			}
1846 			tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1847 				= fpreg.u.bits[0];
1848 			start &= ~0xFUL;
1849 		}
1850 		if (end & 0xF) { /* only write low part */
1851 			if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1852 					&fpreg)) {
1853 				dst->ret = -EIO;
1854 				return;
1855 			}
1856 			tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1857 				= fpreg.u.bits[1];
1858 			end = (end + 0xF) & ~0xFUL;
1859 		}
1860 
1861 		for ( ;	start < end ; start += sizeof(elf_fpreg_t)) {
1862 			index = start / sizeof(elf_fpreg_t);
1863 			if (unw_set_fr(info, index, tmp[index - 2])) {
1864 				dst->ret = -EIO;
1865 				return;
1866 			}
1867 		}
1868 		if (dst->ret || dst->count == 0)
1869 			return;
1870 	}
1871 
1872 	/* fph */
1873 	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1874 		ia64_sync_fph(dst->target);
1875 		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1876 						&dst->u.set.kbuf,
1877 						&dst->u.set.ubuf,
1878 						&dst->target->thread.fph,
1879 						ELF_FP_OFFSET(32), -1);
1880 	}
1881 }
1882 
1883 static int
1884 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1885 	       struct task_struct *target,
1886 	       const struct user_regset *regset,
1887 	       unsigned int pos, unsigned int count,
1888 	       const void *kbuf, const void __user *ubuf)
1889 {
1890 	struct regset_getset info = { .target = target, .regset = regset,
1891 				 .pos = pos, .count = count,
1892 				 .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1893 				 .ret = 0 };
1894 
1895 	if (target == current)
1896 		unw_init_running(call, &info);
1897 	else {
1898 		struct unw_frame_info ufi;
1899 		memset(&ufi, 0, sizeof(ufi));
1900 		unw_init_from_blocked_task(&ufi, target);
1901 		(*call)(&ufi, &info);
1902 	}
1903 
1904 	return info.ret;
1905 }
1906 
1907 static int
1908 gpregs_get(struct task_struct *target,
1909 	   const struct user_regset *regset,
1910 	   unsigned int pos, unsigned int count,
1911 	   void *kbuf, void __user *ubuf)
1912 {
1913 	return do_regset_call(do_gpregs_get, target, regset, pos, count,
1914 		kbuf, ubuf);
1915 }
1916 
1917 static int gpregs_set(struct task_struct *target,
1918 		const struct user_regset *regset,
1919 		unsigned int pos, unsigned int count,
1920 		const void *kbuf, const void __user *ubuf)
1921 {
1922 	return do_regset_call(do_gpregs_set, target, regset, pos, count,
1923 		kbuf, ubuf);
1924 }
1925 
1926 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1927 {
1928 	do_sync_rbs(info, ia64_sync_user_rbs);
1929 }
1930 
1931 /*
1932  * This is called to write back the register backing store.
1933  * ptrace does this before it stops, so that a tracer reading the user
1934  * memory after the thread stops will get the current register data.
1935  */
1936 static int
1937 gpregs_writeback(struct task_struct *target,
1938 		 const struct user_regset *regset,
1939 		 int now)
1940 {
1941 	if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1942 		return 0;
1943 	tsk_set_notify_resume(target);
1944 	return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1945 		NULL, NULL);
1946 }
1947 
1948 static int
1949 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1950 {
1951 	return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1952 }
1953 
1954 static int fpregs_get(struct task_struct *target,
1955 		const struct user_regset *regset,
1956 		unsigned int pos, unsigned int count,
1957 		void *kbuf, void __user *ubuf)
1958 {
1959 	return do_regset_call(do_fpregs_get, target, regset, pos, count,
1960 		kbuf, ubuf);
1961 }
1962 
1963 static int fpregs_set(struct task_struct *target,
1964 		const struct user_regset *regset,
1965 		unsigned int pos, unsigned int count,
1966 		const void *kbuf, const void __user *ubuf)
1967 {
1968 	return do_regset_call(do_fpregs_set, target, regset, pos, count,
1969 		kbuf, ubuf);
1970 }
1971 
1972 static int
1973 access_uarea(struct task_struct *child, unsigned long addr,
1974 	      unsigned long *data, int write_access)
1975 {
1976 	unsigned int pos = -1; /* an invalid value */
1977 	int ret;
1978 	unsigned long *ptr, regnum;
1979 
1980 	if ((addr & 0x7) != 0) {
1981 		dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1982 		return -1;
1983 	}
1984 	if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1985 		(addr >= PT_R7 + 8 && addr < PT_B1) ||
1986 		(addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1987 		(addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1988 		dprintk("ptrace: rejecting access to register "
1989 					"address 0x%lx\n", addr);
1990 		return -1;
1991 	}
1992 
1993 	switch (addr) {
1994 	case PT_F32 ... (PT_F127 + 15):
1995 		pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1996 		break;
1997 	case PT_F2 ... (PT_F5 + 15):
1998 		pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1999 		break;
2000 	case PT_F10 ... (PT_F31 + 15):
2001 		pos = addr - PT_F10 + ELF_FP_OFFSET(10);
2002 		break;
2003 	case PT_F6 ... (PT_F9 + 15):
2004 		pos = addr - PT_F6 + ELF_FP_OFFSET(6);
2005 		break;
2006 	}
2007 
2008 	if (pos != -1) {
2009 		if (write_access)
2010 			ret = fpregs_set(child, NULL, pos,
2011 				sizeof(unsigned long), data, NULL);
2012 		else
2013 			ret = fpregs_get(child, NULL, pos,
2014 				sizeof(unsigned long), data, NULL);
2015 		if (ret != 0)
2016 			return -1;
2017 		return 0;
2018 	}
2019 
2020 	switch (addr) {
2021 	case PT_NAT_BITS:
2022 		pos = ELF_NAT_OFFSET;
2023 		break;
2024 	case PT_R4 ... PT_R7:
2025 		pos = addr - PT_R4 + ELF_GR_OFFSET(4);
2026 		break;
2027 	case PT_B1 ... PT_B5:
2028 		pos = addr - PT_B1 + ELF_BR_OFFSET(1);
2029 		break;
2030 	case PT_AR_EC:
2031 		pos = ELF_AR_EC_OFFSET;
2032 		break;
2033 	case PT_AR_LC:
2034 		pos = ELF_AR_LC_OFFSET;
2035 		break;
2036 	case PT_CR_IPSR:
2037 		pos = ELF_CR_IPSR_OFFSET;
2038 		break;
2039 	case PT_CR_IIP:
2040 		pos = ELF_CR_IIP_OFFSET;
2041 		break;
2042 	case PT_CFM:
2043 		pos = ELF_CFM_OFFSET;
2044 		break;
2045 	case PT_AR_UNAT:
2046 		pos = ELF_AR_UNAT_OFFSET;
2047 		break;
2048 	case PT_AR_PFS:
2049 		pos = ELF_AR_PFS_OFFSET;
2050 		break;
2051 	case PT_AR_RSC:
2052 		pos = ELF_AR_RSC_OFFSET;
2053 		break;
2054 	case PT_AR_RNAT:
2055 		pos = ELF_AR_RNAT_OFFSET;
2056 		break;
2057 	case PT_AR_BSPSTORE:
2058 		pos = ELF_AR_BSPSTORE_OFFSET;
2059 		break;
2060 	case PT_PR:
2061 		pos = ELF_PR_OFFSET;
2062 		break;
2063 	case PT_B6:
2064 		pos = ELF_BR_OFFSET(6);
2065 		break;
2066 	case PT_AR_BSP:
2067 		pos = ELF_AR_BSP_OFFSET;
2068 		break;
2069 	case PT_R1 ... PT_R3:
2070 		pos = addr - PT_R1 + ELF_GR_OFFSET(1);
2071 		break;
2072 	case PT_R12 ... PT_R15:
2073 		pos = addr - PT_R12 + ELF_GR_OFFSET(12);
2074 		break;
2075 	case PT_R8 ... PT_R11:
2076 		pos = addr - PT_R8 + ELF_GR_OFFSET(8);
2077 		break;
2078 	case PT_R16 ... PT_R31:
2079 		pos = addr - PT_R16 + ELF_GR_OFFSET(16);
2080 		break;
2081 	case PT_AR_CCV:
2082 		pos = ELF_AR_CCV_OFFSET;
2083 		break;
2084 	case PT_AR_FPSR:
2085 		pos = ELF_AR_FPSR_OFFSET;
2086 		break;
2087 	case PT_B0:
2088 		pos = ELF_BR_OFFSET(0);
2089 		break;
2090 	case PT_B7:
2091 		pos = ELF_BR_OFFSET(7);
2092 		break;
2093 	case PT_AR_CSD:
2094 		pos = ELF_AR_CSD_OFFSET;
2095 		break;
2096 	case PT_AR_SSD:
2097 		pos = ELF_AR_SSD_OFFSET;
2098 		break;
2099 	}
2100 
2101 	if (pos != -1) {
2102 		if (write_access)
2103 			ret = gpregs_set(child, NULL, pos,
2104 				sizeof(unsigned long), data, NULL);
2105 		else
2106 			ret = gpregs_get(child, NULL, pos,
2107 				sizeof(unsigned long), data, NULL);
2108 		if (ret != 0)
2109 			return -1;
2110 		return 0;
2111 	}
2112 
2113 	/* access debug registers */
2114 	if (addr >= PT_IBR) {
2115 		regnum = (addr - PT_IBR) >> 3;
2116 		ptr = &child->thread.ibr[0];
2117 	} else {
2118 		regnum = (addr - PT_DBR) >> 3;
2119 		ptr = &child->thread.dbr[0];
2120 	}
2121 
2122 	if (regnum >= 8) {
2123 		dprintk("ptrace: rejecting access to register "
2124 				"address 0x%lx\n", addr);
2125 		return -1;
2126 	}
2127 #ifdef CONFIG_PERFMON
2128 	/*
2129 	 * Check if debug registers are used by perfmon. This
2130 	 * test must be done once we know that we can do the
2131 	 * operation, i.e. the arguments are all valid, but
2132 	 * before we start modifying the state.
2133 	 *
2134 	 * Perfmon needs to keep a count of how many processes
2135 	 * are trying to modify the debug registers for system
2136 	 * wide monitoring sessions.
2137 	 *
2138 	 * We also include read access here, because they may
2139 	 * cause the PMU-installed debug register state
2140 	 * (dbr[], ibr[]) to be reset. The two arrays are also
2141 	 * used by perfmon, but we do not use
2142 	 * IA64_THREAD_DBG_VALID. The registers are restored
2143 	 * by the PMU context switch code.
2144 	 */
2145 	if (pfm_use_debug_registers(child))
2146 		return -1;
2147 #endif
2148 
2149 	if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
2150 		child->thread.flags |= IA64_THREAD_DBG_VALID;
2151 		memset(child->thread.dbr, 0,
2152 				sizeof(child->thread.dbr));
2153 		memset(child->thread.ibr, 0,
2154 				sizeof(child->thread.ibr));
2155 	}
2156 
2157 	ptr += regnum;
2158 
2159 	if ((regnum & 1) && write_access) {
2160 		/* don't let the user set kernel-level breakpoints: */
2161 		*ptr = *data & ~(7UL << 56);
2162 		return 0;
2163 	}
2164 	if (write_access)
2165 		*ptr = *data;
2166 	else
2167 		*data = *ptr;
2168 	return 0;
2169 }
2170 
2171 static const struct user_regset native_regsets[] = {
2172 	{
2173 		.core_note_type = NT_PRSTATUS,
2174 		.n = ELF_NGREG,
2175 		.size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2176 		.get = gpregs_get, .set = gpregs_set,
2177 		.writeback = gpregs_writeback
2178 	},
2179 	{
2180 		.core_note_type = NT_PRFPREG,
2181 		.n = ELF_NFPREG,
2182 		.size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2183 		.get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2184 	},
2185 };
2186 
2187 static const struct user_regset_view user_ia64_view = {
2188 	.name = "ia64",
2189 	.e_machine = EM_IA_64,
2190 	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2191 };
2192 
2193 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2194 {
2195 #ifdef CONFIG_IA32_SUPPORT
2196 	extern const struct user_regset_view user_ia32_view;
2197 	if (IS_IA32_PROCESS(task_pt_regs(tsk)))
2198 		return &user_ia32_view;
2199 #endif
2200 	return &user_ia64_view;
2201 }
2202