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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Kernel support for the ptrace() and syscall tracing interfaces.
   4 *
   5 * Copyright (C) 1999-2005 Hewlett-Packard Co
   6 *	David Mosberger-Tang <davidm@hpl.hp.com>
   7 * Copyright (C) 2006 Intel Co
   8 *  2006-08-12	- IA64 Native Utrace implementation support added by
   9 *	Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
  10 *
  11 * Derived from the x86 and Alpha versions.
  12 */
  13#include <linux/kernel.h>
  14#include <linux/sched.h>
  15#include <linux/sched/task.h>
  16#include <linux/sched/task_stack.h>
  17#include <linux/mm.h>
  18#include <linux/errno.h>
  19#include <linux/ptrace.h>
  20#include <linux/user.h>
  21#include <linux/security.h>
  22#include <linux/audit.h>
  23#include <linux/signal.h>
  24#include <linux/regset.h>
  25#include <linux/elf.h>
  26#include <linux/tracehook.h>
  27
  28#include <asm/processor.h>
  29#include <asm/ptrace_offsets.h>
  30#include <asm/rse.h>
  31#include <linux/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
  65static inline int
  66in_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 */
  75unsigned long
  76ia64_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 */
 114unsigned long
 115ia64_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
 152void
 153ia64_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
 175void
 176ia64_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 */
 250static unsigned long
 251get_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 */
 310static void
 311put_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
 383static inline int
 384on_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 */
 403long
 404ia64_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), FOLL_FORCE);
 459	if (copied != sizeof(ret))
 460		return -EIO;
 461	*val = ret;
 462	return 0;
 463}
 464
 465long
 466ia64_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),
 495				FOLL_FORCE | FOLL_WRITE)
 496		   != sizeof(val))
 497		return -EIO;
 498	return 0;
 499}
 500
 501/*
 502 * Calculate the address of the end of the user-level register backing
 503 * store.  This is the address that would have been stored in ar.bsp
 504 * if the user had executed a "cover" instruction right before
 505 * entering the kernel.  If CFMP is not NULL, it is used to return the
 506 * "current frame mask" that was active at the time the kernel was
 507 * entered.
 508 */
 509unsigned long
 510ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
 511		       unsigned long *cfmp)
 512{
 513	unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
 514	long ndirty;
 515
 516	krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 517	bspstore = (unsigned long *) pt->ar_bspstore;
 518	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
 519
 520	if (in_syscall(pt))
 521		ndirty += (cfm & 0x7f);
 522	else
 523		cfm &= ~(1UL << 63);	/* clear valid bit */
 524
 525	if (cfmp)
 526		*cfmp = cfm;
 527	return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
 528}
 529
 530/*
 531 * Synchronize (i.e, write) the RSE backing store living in kernel
 532 * space to the VM of the CHILD task.  SW and PT are the pointers to
 533 * the switch_stack and pt_regs structures, respectively.
 534 * USER_RBS_END is the user-level address at which the backing store
 535 * ends.
 536 */
 537long
 538ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
 539		    unsigned long user_rbs_start, unsigned long user_rbs_end)
 540{
 541	unsigned long addr, val;
 542	long ret;
 543
 544	/* now copy word for word from kernel rbs to user rbs: */
 545	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 546		ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
 547		if (ret < 0)
 548			return ret;
 549		if (access_process_vm(child, addr, &val, sizeof(val),
 550				FOLL_FORCE | FOLL_WRITE)
 551		    != sizeof(val))
 552			return -EIO;
 553	}
 554	return 0;
 555}
 556
 557static long
 558ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
 559		unsigned long user_rbs_start, unsigned long user_rbs_end)
 560{
 561	unsigned long addr, val;
 562	long ret;
 563
 564	/* now copy word for word from user rbs to kernel rbs: */
 565	for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 566		if (access_process_vm(child, addr, &val, sizeof(val),
 567				FOLL_FORCE)
 568				!= sizeof(val))
 569			return -EIO;
 570
 571		ret = ia64_poke(child, sw, user_rbs_end, addr, val);
 572		if (ret < 0)
 573			return ret;
 574	}
 575	return 0;
 576}
 577
 578typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
 579			    unsigned long, unsigned long);
 580
 581static void do_sync_rbs(struct unw_frame_info *info, void *arg)
 582{
 583	struct pt_regs *pt;
 584	unsigned long urbs_end;
 585	syncfunc_t fn = arg;
 586
 587	if (unw_unwind_to_user(info) < 0)
 588		return;
 589	pt = task_pt_regs(info->task);
 590	urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
 591
 592	fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
 593}
 594
 595/*
 596 * when a thread is stopped (ptraced), debugger might change thread's user
 597 * stack (change memory directly), and we must avoid the RSE stored in kernel
 598 * to override user stack (user space's RSE is newer than kernel's in the
 599 * case). To workaround the issue, we copy kernel RSE to user RSE before the
 600 * task is stopped, so user RSE has updated data.  we then copy user RSE to
 601 * kernel after the task is resummed from traced stop and kernel will use the
 602 * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
 603 * synchronize user RSE to kernel.
 604 */
 605void ia64_ptrace_stop(void)
 606{
 607	if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
 608		return;
 609	set_notify_resume(current);
 610	unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
 611}
 612
 613/*
 614 * This is called to read back the register backing store.
 615 */
 616void ia64_sync_krbs(void)
 617{
 618	clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
 619
 620	unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
 621}
 622
 623/*
 624 * After PTRACE_ATTACH, a thread's register backing store area in user
 625 * space is assumed to contain correct data whenever the thread is
 626 * stopped.  arch_ptrace_stop takes care of this on tracing stops.
 627 * But if the child was already stopped for job control when we attach
 628 * to it, then it might not ever get into ptrace_stop by the time we
 629 * want to examine the user memory containing the RBS.
 630 */
 631void
 632ptrace_attach_sync_user_rbs (struct task_struct *child)
 633{
 634	int stopped = 0;
 635	struct unw_frame_info info;
 636
 637	/*
 638	 * If the child is in TASK_STOPPED, we need to change that to
 639	 * TASK_TRACED momentarily while we operate on it.  This ensures
 640	 * that the child won't be woken up and return to user mode while
 641	 * we are doing the sync.  (It can only be woken up for SIGKILL.)
 642	 */
 643
 644	read_lock(&tasklist_lock);
 645	if (child->sighand) {
 646		spin_lock_irq(&child->sighand->siglock);
 647		if (child->state == TASK_STOPPED &&
 648		    !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
 649			set_notify_resume(child);
 650
 651			child->state = TASK_TRACED;
 652			stopped = 1;
 653		}
 654		spin_unlock_irq(&child->sighand->siglock);
 655	}
 656	read_unlock(&tasklist_lock);
 657
 658	if (!stopped)
 659		return;
 660
 661	unw_init_from_blocked_task(&info, child);
 662	do_sync_rbs(&info, ia64_sync_user_rbs);
 663
 664	/*
 665	 * Now move the child back into TASK_STOPPED if it should be in a
 666	 * job control stop, so that SIGCONT can be used to wake it up.
 667	 */
 668	read_lock(&tasklist_lock);
 669	if (child->sighand) {
 670		spin_lock_irq(&child->sighand->siglock);
 671		if (child->state == TASK_TRACED &&
 672		    (child->signal->flags & SIGNAL_STOP_STOPPED)) {
 673			child->state = TASK_STOPPED;
 674		}
 675		spin_unlock_irq(&child->sighand->siglock);
 676	}
 677	read_unlock(&tasklist_lock);
 678}
 679
 680/*
 681 * Write f32-f127 back to task->thread.fph if it has been modified.
 682 */
 683inline void
 684ia64_flush_fph (struct task_struct *task)
 685{
 686	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 687
 688	/*
 689	 * Prevent migrating this task while
 690	 * we're fiddling with the FPU state
 691	 */
 692	preempt_disable();
 693	if (ia64_is_local_fpu_owner(task) && psr->mfh) {
 694		psr->mfh = 0;
 695		task->thread.flags |= IA64_THREAD_FPH_VALID;
 696		ia64_save_fpu(&task->thread.fph[0]);
 697	}
 698	preempt_enable();
 699}
 700
 701/*
 702 * Sync the fph state of the task so that it can be manipulated
 703 * through thread.fph.  If necessary, f32-f127 are written back to
 704 * thread.fph or, if the fph state hasn't been used before, thread.fph
 705 * is cleared to zeroes.  Also, access to f32-f127 is disabled to
 706 * ensure that the task picks up the state from thread.fph when it
 707 * executes again.
 708 */
 709void
 710ia64_sync_fph (struct task_struct *task)
 711{
 712	struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 713
 714	ia64_flush_fph(task);
 715	if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
 716		task->thread.flags |= IA64_THREAD_FPH_VALID;
 717		memset(&task->thread.fph, 0, sizeof(task->thread.fph));
 718	}
 719	ia64_drop_fpu(task);
 720	psr->dfh = 1;
 721}
 722
 723/*
 724 * Change the machine-state of CHILD such that it will return via the normal
 725 * kernel exit-path, rather than the syscall-exit path.
 726 */
 727static void
 728convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
 729			unsigned long cfm)
 730{
 731	struct unw_frame_info info, prev_info;
 732	unsigned long ip, sp, pr;
 733
 734	unw_init_from_blocked_task(&info, child);
 735	while (1) {
 736		prev_info = info;
 737		if (unw_unwind(&info) < 0)
 738			return;
 739
 740		unw_get_sp(&info, &sp);
 741		if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
 742		    < IA64_PT_REGS_SIZE) {
 743			dprintk("ptrace.%s: ran off the top of the kernel "
 744				"stack\n", __func__);
 745			return;
 746		}
 747		if (unw_get_pr (&prev_info, &pr) < 0) {
 748			unw_get_rp(&prev_info, &ip);
 749			dprintk("ptrace.%s: failed to read "
 750				"predicate register (ip=0x%lx)\n",
 751				__func__, ip);
 752			return;
 753		}
 754		if (unw_is_intr_frame(&info)
 755		    && (pr & (1UL << PRED_USER_STACK)))
 756			break;
 757	}
 758
 759	/*
 760	 * Note: at the time of this call, the target task is blocked
 761	 * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
 762	 * (aka, "pLvSys") we redirect execution from
 763	 * .work_pending_syscall_end to .work_processed_kernel.
 764	 */
 765	unw_get_pr(&prev_info, &pr);
 766	pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
 767	pr |=  (1UL << PRED_NON_SYSCALL);
 768	unw_set_pr(&prev_info, pr);
 769
 770	pt->cr_ifs = (1UL << 63) | cfm;
 771	/*
 772	 * Clear the memory that is NOT written on syscall-entry to
 773	 * ensure we do not leak kernel-state to user when execution
 774	 * resumes.
 775	 */
 776	pt->r2 = 0;
 777	pt->r3 = 0;
 778	pt->r14 = 0;
 779	memset(&pt->r16, 0, 16*8);	/* clear r16-r31 */
 780	memset(&pt->f6, 0, 6*16);	/* clear f6-f11 */
 781	pt->b7 = 0;
 782	pt->ar_ccv = 0;
 783	pt->ar_csd = 0;
 784	pt->ar_ssd = 0;
 785}
 786
 787static int
 788access_nat_bits (struct task_struct *child, struct pt_regs *pt,
 789		 struct unw_frame_info *info,
 790		 unsigned long *data, int write_access)
 791{
 792	unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
 793	char nat = 0;
 794
 795	if (write_access) {
 796		nat_bits = *data;
 797		scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
 798		if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
 799			dprintk("ptrace: failed to set ar.unat\n");
 800			return -1;
 801		}
 802		for (regnum = 4; regnum <= 7; ++regnum) {
 803			unw_get_gr(info, regnum, &dummy, &nat);
 804			unw_set_gr(info, regnum, dummy,
 805				   (nat_bits >> regnum) & 1);
 806		}
 807	} else {
 808		if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
 809			dprintk("ptrace: failed to read ar.unat\n");
 810			return -1;
 811		}
 812		nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
 813		for (regnum = 4; regnum <= 7; ++regnum) {
 814			unw_get_gr(info, regnum, &dummy, &nat);
 815			nat_bits |= (nat != 0) << regnum;
 816		}
 817		*data = nat_bits;
 818	}
 819	return 0;
 820}
 821
 822static int
 823access_uarea (struct task_struct *child, unsigned long addr,
 824	      unsigned long *data, int write_access);
 825
 826static long
 827ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 828{
 829	unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
 830	struct unw_frame_info info;
 831	struct ia64_fpreg fpval;
 832	struct switch_stack *sw;
 833	struct pt_regs *pt;
 834	long ret, retval = 0;
 835	char nat = 0;
 836	int i;
 837
 838	if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
 839		return -EIO;
 840
 841	pt = task_pt_regs(child);
 842	sw = (struct switch_stack *) (child->thread.ksp + 16);
 843	unw_init_from_blocked_task(&info, child);
 844	if (unw_unwind_to_user(&info) < 0) {
 845		return -EIO;
 846	}
 847
 848	if (((unsigned long) ppr & 0x7) != 0) {
 849		dprintk("ptrace:unaligned register address %p\n", ppr);
 850		return -EIO;
 851	}
 852
 853	if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
 854	    || access_uarea(child, PT_AR_EC, &ec, 0) < 0
 855	    || access_uarea(child, PT_AR_LC, &lc, 0) < 0
 856	    || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
 857	    || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
 858	    || access_uarea(child, PT_CFM, &cfm, 0)
 859	    || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
 860		return -EIO;
 861
 862	/* control regs */
 863
 864	retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
 865	retval |= __put_user(psr, &ppr->cr_ipsr);
 866
 867	/* app regs */
 868
 869	retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
 870	retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
 871	retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
 872	retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
 873	retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
 874	retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
 875
 876	retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
 877	retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
 878	retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
 879	retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
 880	retval |= __put_user(cfm, &ppr->cfm);
 881
 882	/* gr1-gr3 */
 883
 884	retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
 885	retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
 886
 887	/* gr4-gr7 */
 888
 889	for (i = 4; i < 8; i++) {
 890		if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
 891			return -EIO;
 892		retval |= __put_user(val, &ppr->gr[i]);
 893	}
 894
 895	/* gr8-gr11 */
 896
 897	retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
 898
 899	/* gr12-gr15 */
 900
 901	retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
 902	retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
 903	retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
 904
 905	/* gr16-gr31 */
 906
 907	retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
 908
 909	/* b0 */
 910
 911	retval |= __put_user(pt->b0, &ppr->br[0]);
 912
 913	/* b1-b5 */
 914
 915	for (i = 1; i < 6; i++) {
 916		if (unw_access_br(&info, i, &val, 0) < 0)
 917			return -EIO;
 918		__put_user(val, &ppr->br[i]);
 919	}
 920
 921	/* b6-b7 */
 922
 923	retval |= __put_user(pt->b6, &ppr->br[6]);
 924	retval |= __put_user(pt->b7, &ppr->br[7]);
 925
 926	/* fr2-fr5 */
 927
 928	for (i = 2; i < 6; i++) {
 929		if (unw_get_fr(&info, i, &fpval) < 0)
 930			return -EIO;
 931		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 932	}
 933
 934	/* fr6-fr11 */
 935
 936	retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
 937				 sizeof(struct ia64_fpreg) * 6);
 938
 939	/* fp scratch regs(12-15) */
 940
 941	retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
 942				 sizeof(struct ia64_fpreg) * 4);
 943
 944	/* fr16-fr31 */
 945
 946	for (i = 16; i < 32; i++) {
 947		if (unw_get_fr(&info, i, &fpval) < 0)
 948			return -EIO;
 949		retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 950	}
 951
 952	/* fph */
 953
 954	ia64_flush_fph(child);
 955	retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
 956				 sizeof(ppr->fr[32]) * 96);
 957
 958	/*  preds */
 959
 960	retval |= __put_user(pt->pr, &ppr->pr);
 961
 962	/* nat bits */
 963
 964	retval |= __put_user(nat_bits, &ppr->nat);
 965
 966	ret = retval ? -EIO : 0;
 967	return ret;
 968}
 969
 970static long
 971ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 972{
 973	unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
 974	struct unw_frame_info info;
 975	struct switch_stack *sw;
 976	struct ia64_fpreg fpval;
 977	struct pt_regs *pt;
 978	long ret, retval = 0;
 979	int i;
 980
 981	memset(&fpval, 0, sizeof(fpval));
 982
 983	if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
 984		return -EIO;
 985
 986	pt = task_pt_regs(child);
 987	sw = (struct switch_stack *) (child->thread.ksp + 16);
 988	unw_init_from_blocked_task(&info, child);
 989	if (unw_unwind_to_user(&info) < 0) {
 990		return -EIO;
 991	}
 992
 993	if (((unsigned long) ppr & 0x7) != 0) {
 994		dprintk("ptrace:unaligned register address %p\n", ppr);
 995		return -EIO;
 996	}
 997
 998	/* control regs */
 999
1000	retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
1001	retval |= __get_user(psr, &ppr->cr_ipsr);
1002
1003	/* app regs */
1004
1005	retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1006	retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1007	retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1008	retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1009	retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1010	retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1011
1012	retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1013	retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1014	retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1015	retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1016	retval |= __get_user(cfm, &ppr->cfm);
1017
1018	/* gr1-gr3 */
1019
1020	retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1021	retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1022
1023	/* gr4-gr7 */
1024
1025	for (i = 4; i < 8; i++) {
1026		retval |= __get_user(val, &ppr->gr[i]);
1027		/* NaT bit will be set via PT_NAT_BITS: */
1028		if (unw_set_gr(&info, i, val, 0) < 0)
1029			return -EIO;
1030	}
1031
1032	/* gr8-gr11 */
1033
1034	retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1035
1036	/* gr12-gr15 */
1037
1038	retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1039	retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1040	retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1041
1042	/* gr16-gr31 */
1043
1044	retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1045
1046	/* b0 */
1047
1048	retval |= __get_user(pt->b0, &ppr->br[0]);
1049
1050	/* b1-b5 */
1051
1052	for (i = 1; i < 6; i++) {
1053		retval |= __get_user(val, &ppr->br[i]);
1054		unw_set_br(&info, i, val);
1055	}
1056
1057	/* b6-b7 */
1058
1059	retval |= __get_user(pt->b6, &ppr->br[6]);
1060	retval |= __get_user(pt->b7, &ppr->br[7]);
1061
1062	/* fr2-fr5 */
1063
1064	for (i = 2; i < 6; i++) {
1065		retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1066		if (unw_set_fr(&info, i, fpval) < 0)
1067			return -EIO;
1068	}
1069
1070	/* fr6-fr11 */
1071
1072	retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1073				   sizeof(ppr->fr[6]) * 6);
1074
1075	/* fp scratch regs(12-15) */
1076
1077	retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1078				   sizeof(ppr->fr[12]) * 4);
1079
1080	/* fr16-fr31 */
1081
1082	for (i = 16; i < 32; i++) {
1083		retval |= __copy_from_user(&fpval, &ppr->fr[i],
1084					   sizeof(fpval));
1085		if (unw_set_fr(&info, i, fpval) < 0)
1086			return -EIO;
1087	}
1088
1089	/* fph */
1090
1091	ia64_sync_fph(child);
1092	retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1093				   sizeof(ppr->fr[32]) * 96);
1094
1095	/* preds */
1096
1097	retval |= __get_user(pt->pr, &ppr->pr);
1098
1099	/* nat bits */
1100
1101	retval |= __get_user(nat_bits, &ppr->nat);
1102
1103	retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1104	retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1105	retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1106	retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1107	retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1108	retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1109	retval |= access_uarea(child, PT_CFM, &cfm, 1);
1110	retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1111
1112	ret = retval ? -EIO : 0;
1113	return ret;
1114}
1115
1116void
1117user_enable_single_step (struct task_struct *child)
1118{
1119	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1120
1121	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1122	child_psr->ss = 1;
1123}
1124
1125void
1126user_enable_block_step (struct task_struct *child)
1127{
1128	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1129
1130	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1131	child_psr->tb = 1;
1132}
1133
1134void
1135user_disable_single_step (struct task_struct *child)
1136{
1137	struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1138
1139	/* make sure the single step/taken-branch trap bits are not set: */
1140	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1141	child_psr->ss = 0;
1142	child_psr->tb = 0;
1143}
1144
1145/*
1146 * Called by kernel/ptrace.c when detaching..
1147 *
1148 * Make sure the single step bit is not set.
1149 */
1150void
1151ptrace_disable (struct task_struct *child)
1152{
1153	user_disable_single_step(child);
1154}
1155
1156long
1157arch_ptrace (struct task_struct *child, long request,
1158	     unsigned long addr, unsigned long data)
1159{
1160	switch (request) {
1161	case PTRACE_PEEKTEXT:
1162	case PTRACE_PEEKDATA:
1163		/* read word at location addr */
1164		if (ptrace_access_vm(child, addr, &data, sizeof(data),
1165				FOLL_FORCE)
1166		    != sizeof(data))
1167			return -EIO;
1168		/* ensure return value is not mistaken for error code */
1169		force_successful_syscall_return();
1170		return data;
1171
1172	/* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1173	 * by the generic ptrace_request().
1174	 */
1175
1176	case PTRACE_PEEKUSR:
1177		/* read the word at addr in the USER area */
1178		if (access_uarea(child, addr, &data, 0) < 0)
1179			return -EIO;
1180		/* ensure return value is not mistaken for error code */
1181		force_successful_syscall_return();
1182		return data;
1183
1184	case PTRACE_POKEUSR:
1185		/* write the word at addr in the USER area */
1186		if (access_uarea(child, addr, &data, 1) < 0)
1187			return -EIO;
1188		return 0;
1189
1190	case PTRACE_OLD_GETSIGINFO:
1191		/* for backwards-compatibility */
1192		return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1193
1194	case PTRACE_OLD_SETSIGINFO:
1195		/* for backwards-compatibility */
1196		return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1197
1198	case PTRACE_GETREGS:
1199		return ptrace_getregs(child,
1200				      (struct pt_all_user_regs __user *) data);
1201
1202	case PTRACE_SETREGS:
1203		return ptrace_setregs(child,
1204				      (struct pt_all_user_regs __user *) data);
1205
1206	default:
1207		return ptrace_request(child, request, addr, data);
1208	}
1209}
1210
1211
1212/* "asmlinkage" so the input arguments are preserved... */
1213
1214asmlinkage long
1215syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1216		     long arg4, long arg5, long arg6, long arg7,
1217		     struct pt_regs regs)
1218{
1219	if (test_thread_flag(TIF_SYSCALL_TRACE))
1220		if (tracehook_report_syscall_entry(&regs))
1221			return -ENOSYS;
1222
1223	/* copy user rbs to kernel rbs */
1224	if (test_thread_flag(TIF_RESTORE_RSE))
1225		ia64_sync_krbs();
1226
1227
1228	audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
1229
1230	return 0;
1231}
1232
1233/* "asmlinkage" so the input arguments are preserved... */
1234
1235asmlinkage void
1236syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1237		     long arg4, long arg5, long arg6, long arg7,
1238		     struct pt_regs regs)
1239{
1240	int step;
1241
1242	audit_syscall_exit(&regs);
1243
1244	step = test_thread_flag(TIF_SINGLESTEP);
1245	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1246		tracehook_report_syscall_exit(&regs, step);
1247
1248	/* copy user rbs to kernel rbs */
1249	if (test_thread_flag(TIF_RESTORE_RSE))
1250		ia64_sync_krbs();
1251}
1252
1253/* Utrace implementation starts here */
1254struct regset_get {
1255	void *kbuf;
1256	void __user *ubuf;
1257};
1258
1259struct regset_set {
1260	const void *kbuf;
1261	const void __user *ubuf;
1262};
1263
1264struct regset_getset {
1265	struct task_struct *target;
1266	const struct user_regset *regset;
1267	union {
1268		struct regset_get get;
1269		struct regset_set set;
1270	} u;
1271	unsigned int pos;
1272	unsigned int count;
1273	int ret;
1274};
1275
1276static const ptrdiff_t pt_offsets[32] =
1277{
1278#define R(n) offsetof(struct pt_regs, r##n)
1279	[0] = -1, R(1), R(2), R(3),
1280	[4] = -1, [5] = -1, [6] = -1, [7] = -1,
1281	R(8), R(9), R(10), R(11), R(12), R(13), R(14), R(15),
1282	R(16), R(17), R(18), R(19), R(20), R(21), R(22), R(23),
1283	R(24), R(25), R(26), R(27), R(28), R(29), R(30), R(31),
1284#undef R
1285};
1286
1287static int
1288access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1289		unsigned long addr, unsigned long *data, int write_access)
1290{
1291	struct pt_regs *pt = task_pt_regs(target);
1292	unsigned reg = addr / sizeof(unsigned long);
1293	ptrdiff_t d = pt_offsets[reg];
1294
1295	if (d >= 0) {
1296		unsigned long *ptr = (void *)pt + d;
1297		if (write_access)
1298			*ptr = *data;
1299		else
1300			*data = *ptr;
1301		return 0;
1302	} else {
1303		char nat = 0;
1304		if (write_access) {
1305			/* read NaT bit first: */
1306			unsigned long dummy;
1307			int ret = unw_get_gr(info, reg, &dummy, &nat);
1308			if (ret < 0)
1309				return ret;
1310		}
1311		return unw_access_gr(info, reg, data, &nat, write_access);
1312	}
1313}
1314
1315static int
1316access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1317		unsigned long addr, unsigned long *data, int write_access)
1318{
1319	struct pt_regs *pt;
1320	unsigned long *ptr = NULL;
1321
1322	pt = task_pt_regs(target);
1323	switch (addr) {
1324	case ELF_BR_OFFSET(0):
1325		ptr = &pt->b0;
1326		break;
1327	case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1328		return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1329				     data, write_access);
1330	case ELF_BR_OFFSET(6):
1331		ptr = &pt->b6;
1332		break;
1333	case ELF_BR_OFFSET(7):
1334		ptr = &pt->b7;
1335	}
1336	if (write_access)
1337		*ptr = *data;
1338	else
1339		*data = *ptr;
1340	return 0;
1341}
1342
1343static int
1344access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1345		unsigned long addr, unsigned long *data, int write_access)
1346{
1347	struct pt_regs *pt;
1348	unsigned long cfm, urbs_end;
1349	unsigned long *ptr = NULL;
1350
1351	pt = task_pt_regs(target);
1352	if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1353		switch (addr) {
1354		case ELF_AR_RSC_OFFSET:
1355			/* force PL3 */
1356			if (write_access)
1357				pt->ar_rsc = *data | (3 << 2);
1358			else
1359				*data = pt->ar_rsc;
1360			return 0;
1361		case ELF_AR_BSP_OFFSET:
1362			/*
1363			 * By convention, we use PT_AR_BSP to refer to
1364			 * the end of the user-level backing store.
1365			 * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1366			 * to get the real value of ar.bsp at the time
1367			 * the kernel was entered.
1368			 *
1369			 * Furthermore, when changing the contents of
1370			 * PT_AR_BSP (or PT_CFM) while the task is
1371			 * blocked in a system call, convert the state
1372			 * so that the non-system-call exit
1373			 * path is used.  This ensures that the proper
1374			 * state will be picked up when resuming
1375			 * execution.  However, it *also* means that
1376			 * once we write PT_AR_BSP/PT_CFM, it won't be
1377			 * possible to modify the syscall arguments of
1378			 * the pending system call any longer.  This
1379			 * shouldn't be an issue because modifying
1380			 * PT_AR_BSP/PT_CFM generally implies that
1381			 * we're either abandoning the pending system
1382			 * call or that we defer it's re-execution
1383			 * (e.g., due to GDB doing an inferior
1384			 * function call).
1385			 */
1386			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1387			if (write_access) {
1388				if (*data != urbs_end) {
1389					if (in_syscall(pt))
1390						convert_to_non_syscall(target,
1391								       pt,
1392								       cfm);
1393					/*
1394					 * Simulate user-level write
1395					 * of ar.bsp:
1396					 */
1397					pt->loadrs = 0;
1398					pt->ar_bspstore = *data;
1399				}
1400			} else
1401				*data = urbs_end;
1402			return 0;
1403		case ELF_AR_BSPSTORE_OFFSET:
1404			ptr = &pt->ar_bspstore;
1405			break;
1406		case ELF_AR_RNAT_OFFSET:
1407			ptr = &pt->ar_rnat;
1408			break;
1409		case ELF_AR_CCV_OFFSET:
1410			ptr = &pt->ar_ccv;
1411			break;
1412		case ELF_AR_UNAT_OFFSET:
1413			ptr = &pt->ar_unat;
1414			break;
1415		case ELF_AR_FPSR_OFFSET:
1416			ptr = &pt->ar_fpsr;
1417			break;
1418		case ELF_AR_PFS_OFFSET:
1419			ptr = &pt->ar_pfs;
1420			break;
1421		case ELF_AR_LC_OFFSET:
1422			return unw_access_ar(info, UNW_AR_LC, data,
1423					     write_access);
1424		case ELF_AR_EC_OFFSET:
1425			return unw_access_ar(info, UNW_AR_EC, data,
1426					     write_access);
1427		case ELF_AR_CSD_OFFSET:
1428			ptr = &pt->ar_csd;
1429			break;
1430		case ELF_AR_SSD_OFFSET:
1431			ptr = &pt->ar_ssd;
1432		}
1433	} else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1434		switch (addr) {
1435		case ELF_CR_IIP_OFFSET:
1436			ptr = &pt->cr_iip;
1437			break;
1438		case ELF_CFM_OFFSET:
1439			urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1440			if (write_access) {
1441				if (((cfm ^ *data) & PFM_MASK) != 0) {
1442					if (in_syscall(pt))
1443						convert_to_non_syscall(target,
1444								       pt,
1445								       cfm);
1446					pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1447						      | (*data & PFM_MASK));
1448				}
1449			} else
1450				*data = cfm;
1451			return 0;
1452		case ELF_CR_IPSR_OFFSET:
1453			if (write_access) {
1454				unsigned long tmp = *data;
1455				/* psr.ri==3 is a reserved value: SDM 2:25 */
1456				if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1457					tmp &= ~IA64_PSR_RI;
1458				pt->cr_ipsr = ((tmp & IPSR_MASK)
1459					       | (pt->cr_ipsr & ~IPSR_MASK));
1460			} else
1461				*data = (pt->cr_ipsr & IPSR_MASK);
1462			return 0;
1463		}
1464	} else if (addr == ELF_NAT_OFFSET)
1465		return access_nat_bits(target, pt, info,
1466				       data, write_access);
1467	else if (addr == ELF_PR_OFFSET)
1468		ptr = &pt->pr;
1469	else
1470		return -1;
1471
1472	if (write_access)
1473		*ptr = *data;
1474	else
1475		*data = *ptr;
1476
1477	return 0;
1478}
1479
1480static int
1481access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1482		unsigned long addr, unsigned long *data, int write_access)
1483{
1484	if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(31))
1485		return access_elf_gpreg(target, info, addr, data, write_access);
1486	else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1487		return access_elf_breg(target, info, addr, data, write_access);
1488	else
1489		return access_elf_areg(target, info, addr, data, write_access);
1490}
1491
1492struct regset_membuf {
1493	struct membuf to;
1494	int ret;
1495};
1496
1497void do_gpregs_get(struct unw_frame_info *info, void *arg)
1498{
1499	struct regset_membuf *dst = arg;
1500	struct membuf to = dst->to;
1501	unsigned int n;
1502	elf_greg_t reg;
1503
1504	if (unw_unwind_to_user(info) < 0)
1505		return;
1506
1507	/*
1508	 * coredump format:
1509	 *      r0-r31
1510	 *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1511	 *      predicate registers (p0-p63)
1512	 *      b0-b7
1513	 *      ip cfm user-mask
1514	 *      ar.rsc ar.bsp ar.bspstore ar.rnat
1515	 *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1516	 */
1517
1518
1519	/* Skip r0 */
1520	membuf_zero(&to, 8);
1521	for (n = 8; to.left && n < ELF_AR_END_OFFSET; n += 8) {
1522		if (access_elf_reg(info->task, info, n, &reg, 0) < 0) {
1523			dst->ret = -EIO;
1524			return;
1525		}
1526		membuf_store(&to, reg);
1527	}
1528}
1529
1530void do_gpregs_set(struct unw_frame_info *info, void *arg)
1531{
1532	struct regset_getset *dst = arg;
1533
1534	if (unw_unwind_to_user(info) < 0)
1535		return;
1536
1537	if (!dst->count)
1538		return;
1539	/* Skip r0 */
1540	if (dst->pos < ELF_GR_OFFSET(1)) {
1541		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1542						       &dst->u.set.kbuf,
1543						       &dst->u.set.ubuf,
1544						       0, ELF_GR_OFFSET(1));
1545		if (dst->ret)
1546			return;
1547	}
1548
1549	while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
1550		unsigned int n, from, to;
1551		elf_greg_t tmp[16];
1552
1553		from = dst->pos;
1554		to = from + sizeof(tmp);
1555		if (to > ELF_AR_END_OFFSET)
1556			to = ELF_AR_END_OFFSET;
1557		/* get up to 16 values */
1558		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1559				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1560				from, to);
1561		if (dst->ret)
1562			return;
1563		/* now copy them into registers */
1564		for (n = 0; from < dst->pos; from += sizeof(elf_greg_t), n++)
1565			if (access_elf_reg(dst->target, info, from,
1566						&tmp[n], 1) < 0) {
1567				dst->ret = -EIO;
1568				return;
1569			}
1570	}
1571}
1572
1573#define ELF_FP_OFFSET(i)	(i * sizeof(elf_fpreg_t))
1574
1575void do_fpregs_get(struct unw_frame_info *info, void *arg)
1576{
1577	struct task_struct *task = info->task;
1578	struct regset_membuf *dst = arg;
1579	struct membuf to = dst->to;
1580	elf_fpreg_t reg;
1581	unsigned int n;
1582
1583	if (unw_unwind_to_user(info) < 0)
1584		return;
1585
1586	/* Skip pos 0 and 1 */
1587	membuf_zero(&to, 2 * sizeof(elf_fpreg_t));
1588
1589	/* fr2-fr31 */
1590	for (n = 2; to.left && n < 32; n++) {
1591		if (unw_get_fr(info, n, &reg)) {
1592			dst->ret = -EIO;
1593			return;
1594		}
1595		membuf_write(&to, &reg, sizeof(reg));
1596	}
1597
1598	/* fph */
1599	if (!to.left)
1600		return;
1601
1602	ia64_flush_fph(task);
1603	if (task->thread.flags & IA64_THREAD_FPH_VALID)
1604		membuf_write(&to, &task->thread.fph, 96 * sizeof(reg));
1605	else
1606		membuf_zero(&to, 96 * sizeof(reg));
1607}
1608
1609void do_fpregs_set(struct unw_frame_info *info, void *arg)
1610{
1611	struct regset_getset *dst = arg;
1612	elf_fpreg_t fpreg, tmp[30];
1613	int index, start, end;
1614
1615	if (unw_unwind_to_user(info) < 0)
1616		return;
1617
1618	/* Skip pos 0 and 1 */
1619	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1620		dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1621						       &dst->u.set.kbuf,
1622						       &dst->u.set.ubuf,
1623						       0, ELF_FP_OFFSET(2));
1624		if (dst->count == 0 || dst->ret)
1625			return;
1626	}
1627
1628	/* fr2-fr31 */
1629	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1630		start = dst->pos;
1631		end = min(((unsigned int)ELF_FP_OFFSET(32)),
1632			 dst->pos + dst->count);
1633		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1634				&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1635				ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1636		if (dst->ret)
1637			return;
1638
1639		if (start & 0xF) { /* only write high part */
1640			if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1641					 &fpreg)) {
1642				dst->ret = -EIO;
1643				return;
1644			}
1645			tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1646				= fpreg.u.bits[0];
1647			start &= ~0xFUL;
1648		}
1649		if (end & 0xF) { /* only write low part */
1650			if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1651					&fpreg)) {
1652				dst->ret = -EIO;
1653				return;
1654			}
1655			tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1656				= fpreg.u.bits[1];
1657			end = (end + 0xF) & ~0xFUL;
1658		}
1659
1660		for ( ;	start < end ; start += sizeof(elf_fpreg_t)) {
1661			index = start / sizeof(elf_fpreg_t);
1662			if (unw_set_fr(info, index, tmp[index - 2])) {
1663				dst->ret = -EIO;
1664				return;
1665			}
1666		}
1667		if (dst->ret || dst->count == 0)
1668			return;
1669	}
1670
1671	/* fph */
1672	if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1673		ia64_sync_fph(dst->target);
1674		dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1675						&dst->u.set.kbuf,
1676						&dst->u.set.ubuf,
1677						&dst->target->thread.fph,
1678						ELF_FP_OFFSET(32), -1);
1679	}
1680}
1681
1682static void
1683unwind_and_call(void (*call)(struct unw_frame_info *, void *),
1684	       struct task_struct *target, void *data)
1685{
1686	if (target == current)
1687		unw_init_running(call, data);
1688	else {
1689		struct unw_frame_info info;
1690		memset(&info, 0, sizeof(info));
1691		unw_init_from_blocked_task(&info, target);
1692		(*call)(&info, data);
1693	}
1694}
1695
1696static int
1697do_regset_call(void (*call)(struct unw_frame_info *, void *),
1698	       struct task_struct *target,
1699	       const struct user_regset *regset,
1700	       unsigned int pos, unsigned int count,
1701	       const void *kbuf, const void __user *ubuf)
1702{
1703	struct regset_getset info = { .target = target, .regset = regset,
1704				 .pos = pos, .count = count,
1705				 .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1706				 .ret = 0 };
1707	unwind_and_call(call, target, &info);
1708	return info.ret;
1709}
1710
1711static int
1712gpregs_get(struct task_struct *target,
1713	   const struct user_regset *regset,
1714	   struct membuf to)
1715{
1716	struct regset_membuf info = {.to = to};
1717	unwind_and_call(do_gpregs_get, target, &info);
1718	return info.ret;
1719}
1720
1721static int gpregs_set(struct task_struct *target,
1722		const struct user_regset *regset,
1723		unsigned int pos, unsigned int count,
1724		const void *kbuf, const void __user *ubuf)
1725{
1726	return do_regset_call(do_gpregs_set, target, regset, pos, count,
1727		kbuf, ubuf);
1728}
1729
1730static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1731{
1732	do_sync_rbs(info, ia64_sync_user_rbs);
1733}
1734
1735/*
1736 * This is called to write back the register backing store.
1737 * ptrace does this before it stops, so that a tracer reading the user
1738 * memory after the thread stops will get the current register data.
1739 */
1740static int
1741gpregs_writeback(struct task_struct *target,
1742		 const struct user_regset *regset,
1743		 int now)
1744{
1745	if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1746		return 0;
1747	set_notify_resume(target);
1748	return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1749		NULL, NULL);
1750}
1751
1752static int
1753fpregs_active(struct task_struct *target, const struct user_regset *regset)
1754{
1755	return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1756}
1757
1758static int fpregs_get(struct task_struct *target,
1759		const struct user_regset *regset,
1760		struct membuf to)
1761{
1762	struct regset_membuf info = {.to = to};
1763	unwind_and_call(do_fpregs_get, target, &info);
1764	return info.ret;
1765}
1766
1767static int fpregs_set(struct task_struct *target,
1768		const struct user_regset *regset,
1769		unsigned int pos, unsigned int count,
1770		const void *kbuf, const void __user *ubuf)
1771{
1772	return do_regset_call(do_fpregs_set, target, regset, pos, count,
1773		kbuf, ubuf);
1774}
1775
1776static int
1777access_uarea(struct task_struct *child, unsigned long addr,
1778	      unsigned long *data, int write_access)
1779{
1780	unsigned int pos = -1; /* an invalid value */
1781	unsigned long *ptr, regnum;
1782
1783	if ((addr & 0x7) != 0) {
1784		dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1785		return -1;
1786	}
1787	if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1788		(addr >= PT_R7 + 8 && addr < PT_B1) ||
1789		(addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1790		(addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1791		dprintk("ptrace: rejecting access to register "
1792					"address 0x%lx\n", addr);
1793		return -1;
1794	}
1795
1796	switch (addr) {
1797	case PT_F32 ... (PT_F127 + 15):
1798		pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1799		break;
1800	case PT_F2 ... (PT_F5 + 15):
1801		pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1802		break;
1803	case PT_F10 ... (PT_F31 + 15):
1804		pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1805		break;
1806	case PT_F6 ... (PT_F9 + 15):
1807		pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1808		break;
1809	}
1810
1811	if (pos != -1) {
1812		unsigned reg = pos / sizeof(elf_fpreg_t);
1813		int which_half = (pos / sizeof(unsigned long)) & 1;
1814
1815		if (reg < 32) { /* fr2-fr31 */
1816			struct unw_frame_info info;
1817			elf_fpreg_t fpreg;
1818
1819			memset(&info, 0, sizeof(info));
1820			unw_init_from_blocked_task(&info, child);
1821			if (unw_unwind_to_user(&info) < 0)
1822				return 0;
1823
1824			if (unw_get_fr(&info, reg, &fpreg))
1825				return -1;
1826			if (write_access) {
1827				fpreg.u.bits[which_half] = *data;
1828				if (unw_set_fr(&info, reg, fpreg))
1829					return -1;
1830			} else {
1831				*data = fpreg.u.bits[which_half];
1832			}
1833		} else { /* fph */
1834			elf_fpreg_t *p = &child->thread.fph[reg - 32];
1835			unsigned long *bits = &p->u.bits[which_half];
1836
1837			ia64_sync_fph(child);
1838			if (write_access)
1839				*bits = *data;
1840			else if (child->thread.flags & IA64_THREAD_FPH_VALID)
1841				*data = *bits;
1842			else
1843				*data = 0;
1844		}
1845		return 0;
1846	}
1847
1848	switch (addr) {
1849	case PT_NAT_BITS:
1850		pos = ELF_NAT_OFFSET;
1851		break;
1852	case PT_R4 ... PT_R7:
1853		pos = addr - PT_R4 + ELF_GR_OFFSET(4);
1854		break;
1855	case PT_B1 ... PT_B5:
1856		pos = addr - PT_B1 + ELF_BR_OFFSET(1);
1857		break;
1858	case PT_AR_EC:
1859		pos = ELF_AR_EC_OFFSET;
1860		break;
1861	case PT_AR_LC:
1862		pos = ELF_AR_LC_OFFSET;
1863		break;
1864	case PT_CR_IPSR:
1865		pos = ELF_CR_IPSR_OFFSET;
1866		break;
1867	case PT_CR_IIP:
1868		pos = ELF_CR_IIP_OFFSET;
1869		break;
1870	case PT_CFM:
1871		pos = ELF_CFM_OFFSET;
1872		break;
1873	case PT_AR_UNAT:
1874		pos = ELF_AR_UNAT_OFFSET;
1875		break;
1876	case PT_AR_PFS:
1877		pos = ELF_AR_PFS_OFFSET;
1878		break;
1879	case PT_AR_RSC:
1880		pos = ELF_AR_RSC_OFFSET;
1881		break;
1882	case PT_AR_RNAT:
1883		pos = ELF_AR_RNAT_OFFSET;
1884		break;
1885	case PT_AR_BSPSTORE:
1886		pos = ELF_AR_BSPSTORE_OFFSET;
1887		break;
1888	case PT_PR:
1889		pos = ELF_PR_OFFSET;
1890		break;
1891	case PT_B6:
1892		pos = ELF_BR_OFFSET(6);
1893		break;
1894	case PT_AR_BSP:
1895		pos = ELF_AR_BSP_OFFSET;
1896		break;
1897	case PT_R1 ... PT_R3:
1898		pos = addr - PT_R1 + ELF_GR_OFFSET(1);
1899		break;
1900	case PT_R12 ... PT_R15:
1901		pos = addr - PT_R12 + ELF_GR_OFFSET(12);
1902		break;
1903	case PT_R8 ... PT_R11:
1904		pos = addr - PT_R8 + ELF_GR_OFFSET(8);
1905		break;
1906	case PT_R16 ... PT_R31:
1907		pos = addr - PT_R16 + ELF_GR_OFFSET(16);
1908		break;
1909	case PT_AR_CCV:
1910		pos = ELF_AR_CCV_OFFSET;
1911		break;
1912	case PT_AR_FPSR:
1913		pos = ELF_AR_FPSR_OFFSET;
1914		break;
1915	case PT_B0:
1916		pos = ELF_BR_OFFSET(0);
1917		break;
1918	case PT_B7:
1919		pos = ELF_BR_OFFSET(7);
1920		break;
1921	case PT_AR_CSD:
1922		pos = ELF_AR_CSD_OFFSET;
1923		break;
1924	case PT_AR_SSD:
1925		pos = ELF_AR_SSD_OFFSET;
1926		break;
1927	}
1928
1929	if (pos != -1) {
1930		struct unw_frame_info info;
1931
1932		memset(&info, 0, sizeof(info));
1933		unw_init_from_blocked_task(&info, child);
1934		if (unw_unwind_to_user(&info) < 0)
1935			return 0;
1936
1937		return access_elf_reg(child, &info, pos, data, write_access);
1938	}
1939
1940	/* access debug registers */
1941	if (addr >= PT_IBR) {
1942		regnum = (addr - PT_IBR) >> 3;
1943		ptr = &child->thread.ibr[0];
1944	} else {
1945		regnum = (addr - PT_DBR) >> 3;
1946		ptr = &child->thread.dbr[0];
1947	}
1948
1949	if (regnum >= 8) {
1950		dprintk("ptrace: rejecting access to register "
1951				"address 0x%lx\n", addr);
1952		return -1;
1953	}
1954#ifdef CONFIG_PERFMON
1955	/*
1956	 * Check if debug registers are used by perfmon. This
1957	 * test must be done once we know that we can do the
1958	 * operation, i.e. the arguments are all valid, but
1959	 * before we start modifying the state.
1960	 *
1961	 * Perfmon needs to keep a count of how many processes
1962	 * are trying to modify the debug registers for system
1963	 * wide monitoring sessions.
1964	 *
1965	 * We also include read access here, because they may
1966	 * cause the PMU-installed debug register state
1967	 * (dbr[], ibr[]) to be reset. The two arrays are also
1968	 * used by perfmon, but we do not use
1969	 * IA64_THREAD_DBG_VALID. The registers are restored
1970	 * by the PMU context switch code.
1971	 */
1972	if (pfm_use_debug_registers(child))
1973		return -1;
1974#endif
1975
1976	if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
1977		child->thread.flags |= IA64_THREAD_DBG_VALID;
1978		memset(child->thread.dbr, 0,
1979				sizeof(child->thread.dbr));
1980		memset(child->thread.ibr, 0,
1981				sizeof(child->thread.ibr));
1982	}
1983
1984	ptr += regnum;
1985
1986	if ((regnum & 1) && write_access) {
1987		/* don't let the user set kernel-level breakpoints: */
1988		*ptr = *data & ~(7UL << 56);
1989		return 0;
1990	}
1991	if (write_access)
1992		*ptr = *data;
1993	else
1994		*data = *ptr;
1995	return 0;
1996}
1997
1998static const struct user_regset native_regsets[] = {
1999	{
2000		.core_note_type = NT_PRSTATUS,
2001		.n = ELF_NGREG,
2002		.size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2003		.regset_get = gpregs_get, .set = gpregs_set,
2004		.writeback = gpregs_writeback
2005	},
2006	{
2007		.core_note_type = NT_PRFPREG,
2008		.n = ELF_NFPREG,
2009		.size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2010		.regset_get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2011	},
2012};
2013
2014static const struct user_regset_view user_ia64_view = {
2015	.name = "ia64",
2016	.e_machine = EM_IA_64,
2017	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2018};
2019
2020const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2021{
2022	return &user_ia64_view;
2023}
2024
2025struct syscall_get_set_args {
2026	unsigned int i;
2027	unsigned int n;
2028	unsigned long *args;
2029	struct pt_regs *regs;
2030	int rw;
2031};
2032
2033static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2034{
2035	struct syscall_get_set_args *args = data;
2036	struct pt_regs *pt = args->regs;
2037	unsigned long *krbs, cfm, ndirty;
2038	int i, count;
2039
2040	if (unw_unwind_to_user(info) < 0)
2041		return;
2042
2043	cfm = pt->cr_ifs;
2044	krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2045	ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2046
2047	count = 0;
2048	if (in_syscall(pt))
2049		count = min_t(int, args->n, cfm & 0x7f);
2050
2051	for (i = 0; i < count; i++) {
2052		if (args->rw)
2053			*ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
2054				args->args[i];
2055		else
2056			args->args[i] = *ia64_rse_skip_regs(krbs,
2057				ndirty + i + args->i);
2058	}
2059
2060	if (!args->rw) {
2061		while (i < args->n) {
2062			args->args[i] = 0;
2063			i++;
2064		}
2065	}
2066}
2067
2068void ia64_syscall_get_set_arguments(struct task_struct *task,
2069	struct pt_regs *regs, unsigned long *args, int rw)
2070{
2071	struct syscall_get_set_args data = {
2072		.i = 0,
2073		.n = 6,
2074		.args = args,
2075		.regs = regs,
2076		.rw = rw,
2077	};
2078
2079	if (task == current)
2080		unw_init_running(syscall_get_set_args_cb, &data);
2081	else {
2082		struct unw_frame_info ufi;
2083		memset(&ufi, 0, sizeof(ufi));
2084		unw_init_from_blocked_task(&ufi, task);
2085		syscall_get_set_args_cb(&ufi, &data);
2086	}
2087}