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v3.1
   1/*
   2 *  Ptrace user space interface.
   3 *
   4 *    Copyright IBM Corp. 1999,2010
   5 *    Author(s): Denis Joseph Barrow
   6 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/sched.h>
  11#include <linux/mm.h>
  12#include <linux/smp.h>
  13#include <linux/errno.h>
  14#include <linux/ptrace.h>
  15#include <linux/user.h>
  16#include <linux/security.h>
  17#include <linux/audit.h>
  18#include <linux/signal.h>
  19#include <linux/elf.h>
  20#include <linux/regset.h>
  21#include <linux/tracehook.h>
  22#include <linux/seccomp.h>
 
  23#include <trace/syscall.h>
  24#include <asm/compat.h>
  25#include <asm/segment.h>
  26#include <asm/page.h>
  27#include <asm/pgtable.h>
  28#include <asm/pgalloc.h>
  29#include <asm/system.h>
  30#include <asm/uaccess.h>
  31#include <asm/unistd.h>
 
  32#include "entry.h"
  33
  34#ifdef CONFIG_COMPAT
  35#include "compat_ptrace.h"
  36#endif
  37
  38#define CREATE_TRACE_POINTS
  39#include <trace/events/syscalls.h>
  40
  41enum s390_regset {
  42	REGSET_GENERAL,
  43	REGSET_FP,
  44	REGSET_LAST_BREAK,
 
  45	REGSET_GENERAL_EXTENDED,
  46};
  47
  48void update_per_regs(struct task_struct *task)
  49{
  50	static const struct per_regs per_single_step = {
  51		.control = PER_EVENT_IFETCH,
  52		.start = 0,
  53		.end = PSW_ADDR_INSN,
  54	};
  55	struct pt_regs *regs = task_pt_regs(task);
  56	struct thread_struct *thread = &task->thread;
  57	const struct per_regs *new;
  58	struct per_regs old;
  59
  60	/* TIF_SINGLE_STEP overrides the user specified PER registers. */
  61	new = test_tsk_thread_flag(task, TIF_SINGLE_STEP) ?
  62		&per_single_step : &thread->per_user;
 
 
 
 
 
 
 
 
  63
  64	/* Take care of the PER enablement bit in the PSW. */
  65	if (!(new->control & PER_EVENT_MASK)) {
  66		regs->psw.mask &= ~PSW_MASK_PER;
  67		return;
  68	}
  69	regs->psw.mask |= PSW_MASK_PER;
  70	__ctl_store(old, 9, 11);
  71	if (memcmp(new, &old, sizeof(struct per_regs)) != 0)
  72		__ctl_load(*new, 9, 11);
  73}
  74
  75void user_enable_single_step(struct task_struct *task)
  76{
  77	set_tsk_thread_flag(task, TIF_SINGLE_STEP);
  78	if (task == current)
  79		update_per_regs(task);
  80}
  81
  82void user_disable_single_step(struct task_struct *task)
  83{
  84	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
  85	if (task == current)
  86		update_per_regs(task);
  87}
  88
  89/*
  90 * Called by kernel/ptrace.c when detaching..
  91 *
  92 * Clear all debugging related fields.
  93 */
  94void ptrace_disable(struct task_struct *task)
  95{
  96	memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
  97	memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
  98	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
  99	clear_tsk_thread_flag(task, TIF_PER_TRAP);
 100}
 101
 102#ifndef CONFIG_64BIT
 103# define __ADDR_MASK 3
 104#else
 105# define __ADDR_MASK 7
 106#endif
 107
 108static inline unsigned long __peek_user_per(struct task_struct *child,
 109					    addr_t addr)
 110{
 111	struct per_struct_kernel *dummy = NULL;
 112
 113	if (addr == (addr_t) &dummy->cr9)
 114		/* Control bits of the active per set. */
 115		return test_thread_flag(TIF_SINGLE_STEP) ?
 116			PER_EVENT_IFETCH : child->thread.per_user.control;
 117	else if (addr == (addr_t) &dummy->cr10)
 118		/* Start address of the active per set. */
 119		return test_thread_flag(TIF_SINGLE_STEP) ?
 120			0 : child->thread.per_user.start;
 121	else if (addr == (addr_t) &dummy->cr11)
 122		/* End address of the active per set. */
 123		return test_thread_flag(TIF_SINGLE_STEP) ?
 124			PSW_ADDR_INSN : child->thread.per_user.end;
 125	else if (addr == (addr_t) &dummy->bits)
 126		/* Single-step bit. */
 127		return test_thread_flag(TIF_SINGLE_STEP) ?
 128			(1UL << (BITS_PER_LONG - 1)) : 0;
 129	else if (addr == (addr_t) &dummy->starting_addr)
 130		/* Start address of the user specified per set. */
 131		return child->thread.per_user.start;
 132	else if (addr == (addr_t) &dummy->ending_addr)
 133		/* End address of the user specified per set. */
 134		return child->thread.per_user.end;
 135	else if (addr == (addr_t) &dummy->perc_atmid)
 136		/* PER code, ATMID and AI of the last PER trap */
 137		return (unsigned long)
 138			child->thread.per_event.cause << (BITS_PER_LONG - 16);
 139	else if (addr == (addr_t) &dummy->address)
 140		/* Address of the last PER trap */
 141		return child->thread.per_event.address;
 142	else if (addr == (addr_t) &dummy->access_id)
 143		/* Access id of the last PER trap */
 144		return (unsigned long)
 145			child->thread.per_event.paid << (BITS_PER_LONG - 8);
 146	return 0;
 147}
 148
 149/*
 150 * Read the word at offset addr from the user area of a process. The
 151 * trouble here is that the information is littered over different
 152 * locations. The process registers are found on the kernel stack,
 153 * the floating point stuff and the trace settings are stored in
 154 * the task structure. In addition the different structures in
 155 * struct user contain pad bytes that should be read as zeroes.
 156 * Lovely...
 157 */
 158static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 159{
 160	struct user *dummy = NULL;
 161	addr_t offset, tmp;
 162
 163	if (addr < (addr_t) &dummy->regs.acrs) {
 164		/*
 165		 * psw and gprs are stored on the stack
 166		 */
 167		tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 168		if (addr == (addr_t) &dummy->regs.psw.mask)
 169			/* Remove per bit from user psw. */
 170			tmp &= ~PSW_MASK_PER;
 171
 172	} else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 173		/*
 174		 * access registers are stored in the thread structure
 175		 */
 176		offset = addr - (addr_t) &dummy->regs.acrs;
 177#ifdef CONFIG_64BIT
 178		/*
 179		 * Very special case: old & broken 64 bit gdb reading
 180		 * from acrs[15]. Result is a 64 bit value. Read the
 181		 * 32 bit acrs[15] value and shift it by 32. Sick...
 182		 */
 183		if (addr == (addr_t) &dummy->regs.acrs[15])
 184			tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 185		else
 186#endif
 187		tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 188
 189	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 190		/*
 191		 * orig_gpr2 is stored on the kernel stack
 192		 */
 193		tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 194
 195	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
 196		/*
 197		 * prevent reads of padding hole between
 198		 * orig_gpr2 and fp_regs on s390.
 199		 */
 200		tmp = 0;
 201
 202	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 203		/* 
 204		 * floating point regs. are stored in the thread structure
 205		 */
 206		offset = addr - (addr_t) &dummy->regs.fp_regs;
 207		tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
 208		if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
 209			tmp &= (unsigned long) FPC_VALID_MASK
 210				<< (BITS_PER_LONG - 32);
 211
 212	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 213		/*
 214		 * Handle access to the per_info structure.
 215		 */
 216		addr -= (addr_t) &dummy->regs.per_info;
 217		tmp = __peek_user_per(child, addr);
 218
 219	} else
 220		tmp = 0;
 221
 222	return tmp;
 223}
 224
 225static int
 226peek_user(struct task_struct *child, addr_t addr, addr_t data)
 227{
 228	addr_t tmp, mask;
 229
 230	/*
 231	 * Stupid gdb peeks/pokes the access registers in 64 bit with
 232	 * an alignment of 4. Programmers from hell...
 233	 */
 234	mask = __ADDR_MASK;
 235#ifdef CONFIG_64BIT
 236	if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 237	    addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 238		mask = 3;
 239#endif
 240	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 241		return -EIO;
 242
 243	tmp = __peek_user(child, addr);
 244	return put_user(tmp, (addr_t __user *) data);
 245}
 246
 247static inline void __poke_user_per(struct task_struct *child,
 248				   addr_t addr, addr_t data)
 249{
 250	struct per_struct_kernel *dummy = NULL;
 251
 252	/*
 253	 * There are only three fields in the per_info struct that the
 254	 * debugger user can write to.
 255	 * 1) cr9: the debugger wants to set a new PER event mask
 256	 * 2) starting_addr: the debugger wants to set a new starting
 257	 *    address to use with the PER event mask.
 258	 * 3) ending_addr: the debugger wants to set a new ending
 259	 *    address to use with the PER event mask.
 260	 * The user specified PER event mask and the start and end
 261	 * addresses are used only if single stepping is not in effect.
 262	 * Writes to any other field in per_info are ignored.
 263	 */
 264	if (addr == (addr_t) &dummy->cr9)
 265		/* PER event mask of the user specified per set. */
 266		child->thread.per_user.control =
 267			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 268	else if (addr == (addr_t) &dummy->starting_addr)
 269		/* Starting address of the user specified per set. */
 270		child->thread.per_user.start = data;
 271	else if (addr == (addr_t) &dummy->ending_addr)
 272		/* Ending address of the user specified per set. */
 273		child->thread.per_user.end = data;
 274}
 275
 276/*
 277 * Write a word to the user area of a process at location addr. This
 278 * operation does have an additional problem compared to peek_user.
 279 * Stores to the program status word and on the floating point
 280 * control register needs to get checked for validity.
 281 */
 282static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 283{
 284	struct user *dummy = NULL;
 285	addr_t offset;
 286
 287	if (addr < (addr_t) &dummy->regs.acrs) {
 288		/*
 289		 * psw and gprs are stored on the stack
 290		 */
 291		if (addr == (addr_t) &dummy->regs.psw.mask &&
 292#ifdef CONFIG_COMPAT
 293		    data != PSW_MASK_MERGE(psw_user32_bits, data) &&
 294#endif
 295		    data != PSW_MASK_MERGE(psw_user_bits, data))
 296			/* Invalid psw mask. */
 297			return -EINVAL;
 298#ifndef CONFIG_64BIT
 299		if (addr == (addr_t) &dummy->regs.psw.addr)
 300			/* I'd like to reject addresses without the
 301			   high order bit but older gdb's rely on it */
 302			data |= PSW_ADDR_AMODE;
 303#endif
 304		*(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 305
 306	} else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 307		/*
 308		 * access registers are stored in the thread structure
 309		 */
 310		offset = addr - (addr_t) &dummy->regs.acrs;
 311#ifdef CONFIG_64BIT
 312		/*
 313		 * Very special case: old & broken 64 bit gdb writing
 314		 * to acrs[15] with a 64 bit value. Ignore the lower
 315		 * half of the value and write the upper 32 bit to
 316		 * acrs[15]. Sick...
 317		 */
 318		if (addr == (addr_t) &dummy->regs.acrs[15])
 319			child->thread.acrs[15] = (unsigned int) (data >> 32);
 320		else
 321#endif
 322		*(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 323
 324	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 325		/*
 326		 * orig_gpr2 is stored on the kernel stack
 327		 */
 328		task_pt_regs(child)->orig_gpr2 = data;
 329
 330	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
 331		/*
 332		 * prevent writes of padding hole between
 333		 * orig_gpr2 and fp_regs on s390.
 334		 */
 335		return 0;
 336
 337	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 338		/*
 339		 * floating point regs. are stored in the thread structure
 340		 */
 341		if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
 342		    (data & ~((unsigned long) FPC_VALID_MASK
 343			      << (BITS_PER_LONG - 32))) != 0)
 344			return -EINVAL;
 345		offset = addr - (addr_t) &dummy->regs.fp_regs;
 346		*(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
 347
 348	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 349		/*
 350		 * Handle access to the per_info structure.
 351		 */
 352		addr -= (addr_t) &dummy->regs.per_info;
 353		__poke_user_per(child, addr, data);
 354
 355	}
 356
 357	return 0;
 358}
 359
 360static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 361{
 362	addr_t mask;
 363
 364	/*
 365	 * Stupid gdb peeks/pokes the access registers in 64 bit with
 366	 * an alignment of 4. Programmers from hell indeed...
 367	 */
 368	mask = __ADDR_MASK;
 369#ifdef CONFIG_64BIT
 370	if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 371	    addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 372		mask = 3;
 373#endif
 374	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 375		return -EIO;
 376
 377	return __poke_user(child, addr, data);
 378}
 379
 380long arch_ptrace(struct task_struct *child, long request,
 381		 unsigned long addr, unsigned long data)
 382{
 383	ptrace_area parea; 
 384	int copied, ret;
 385
 386	switch (request) {
 387	case PTRACE_PEEKUSR:
 388		/* read the word at location addr in the USER area. */
 389		return peek_user(child, addr, data);
 390
 391	case PTRACE_POKEUSR:
 392		/* write the word at location addr in the USER area */
 393		return poke_user(child, addr, data);
 394
 395	case PTRACE_PEEKUSR_AREA:
 396	case PTRACE_POKEUSR_AREA:
 397		if (copy_from_user(&parea, (void __force __user *) addr,
 398							sizeof(parea)))
 399			return -EFAULT;
 400		addr = parea.kernel_addr;
 401		data = parea.process_addr;
 402		copied = 0;
 403		while (copied < parea.len) {
 404			if (request == PTRACE_PEEKUSR_AREA)
 405				ret = peek_user(child, addr, data);
 406			else {
 407				addr_t utmp;
 408				if (get_user(utmp,
 409					     (addr_t __force __user *) data))
 410					return -EFAULT;
 411				ret = poke_user(child, addr, utmp);
 412			}
 413			if (ret)
 414				return ret;
 415			addr += sizeof(unsigned long);
 416			data += sizeof(unsigned long);
 417			copied += sizeof(unsigned long);
 418		}
 419		return 0;
 420	case PTRACE_GET_LAST_BREAK:
 421		put_user(task_thread_info(child)->last_break,
 422			 (unsigned long __user *) data);
 423		return 0;
 424	default:
 425		/* Removing high order bit from addr (only for 31 bit). */
 426		addr &= PSW_ADDR_INSN;
 427		return ptrace_request(child, request, addr, data);
 428	}
 429}
 430
 431#ifdef CONFIG_COMPAT
 432/*
 433 * Now the fun part starts... a 31 bit program running in the
 434 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 435 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 436 * to handle, the difference to the 64 bit versions of the requests
 437 * is that the access is done in multiples of 4 byte instead of
 438 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 439 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 440 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 441 * is a 31 bit program too, the content of struct user can be
 442 * emulated. A 31 bit program peeking into the struct user of
 443 * a 64 bit program is a no-no.
 444 */
 445
 446/*
 447 * Same as peek_user_per but for a 31 bit program.
 448 */
 449static inline __u32 __peek_user_per_compat(struct task_struct *child,
 450					   addr_t addr)
 451{
 452	struct compat_per_struct_kernel *dummy32 = NULL;
 453
 454	if (addr == (addr_t) &dummy32->cr9)
 455		/* Control bits of the active per set. */
 456		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 457			PER_EVENT_IFETCH : child->thread.per_user.control;
 458	else if (addr == (addr_t) &dummy32->cr10)
 459		/* Start address of the active per set. */
 460		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 461			0 : child->thread.per_user.start;
 462	else if (addr == (addr_t) &dummy32->cr11)
 463		/* End address of the active per set. */
 464		return test_thread_flag(TIF_SINGLE_STEP) ?
 465			PSW32_ADDR_INSN : child->thread.per_user.end;
 466	else if (addr == (addr_t) &dummy32->bits)
 467		/* Single-step bit. */
 468		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 469			0x80000000 : 0;
 470	else if (addr == (addr_t) &dummy32->starting_addr)
 471		/* Start address of the user specified per set. */
 472		return (__u32) child->thread.per_user.start;
 473	else if (addr == (addr_t) &dummy32->ending_addr)
 474		/* End address of the user specified per set. */
 475		return (__u32) child->thread.per_user.end;
 476	else if (addr == (addr_t) &dummy32->perc_atmid)
 477		/* PER code, ATMID and AI of the last PER trap */
 478		return (__u32) child->thread.per_event.cause << 16;
 479	else if (addr == (addr_t) &dummy32->address)
 480		/* Address of the last PER trap */
 481		return (__u32) child->thread.per_event.address;
 482	else if (addr == (addr_t) &dummy32->access_id)
 483		/* Access id of the last PER trap */
 484		return (__u32) child->thread.per_event.paid << 24;
 485	return 0;
 486}
 487
 488/*
 489 * Same as peek_user but for a 31 bit program.
 490 */
 491static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 492{
 493	struct compat_user *dummy32 = NULL;
 494	addr_t offset;
 495	__u32 tmp;
 496
 497	if (addr < (addr_t) &dummy32->regs.acrs) {
 
 498		/*
 499		 * psw and gprs are stored on the stack
 500		 */
 501		if (addr == (addr_t) &dummy32->regs.psw.mask) {
 502			/* Fake a 31 bit psw mask. */
 503			tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
 504			tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
 505		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 506			/* Fake a 31 bit psw address. */
 507			tmp = (__u32) task_pt_regs(child)->psw.addr |
 508				PSW32_ADDR_AMODE31;
 509		} else {
 510			/* gpr 0-15 */
 511			tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
 512					 addr*2 + 4);
 513		}
 514	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 515		/*
 516		 * access registers are stored in the thread structure
 517		 */
 518		offset = addr - (addr_t) &dummy32->regs.acrs;
 519		tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 520
 521	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 522		/*
 523		 * orig_gpr2 is stored on the kernel stack
 524		 */
 525		tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 526
 527	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 528		/*
 529		 * prevent reads of padding hole between
 530		 * orig_gpr2 and fp_regs on s390.
 531		 */
 532		tmp = 0;
 533
 534	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 535		/*
 536		 * floating point regs. are stored in the thread structure 
 537		 */
 538	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
 539		tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
 540
 541	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 542		/*
 543		 * Handle access to the per_info structure.
 544		 */
 545		addr -= (addr_t) &dummy32->regs.per_info;
 546		tmp = __peek_user_per_compat(child, addr);
 547
 548	} else
 549		tmp = 0;
 550
 551	return tmp;
 552}
 553
 554static int peek_user_compat(struct task_struct *child,
 555			    addr_t addr, addr_t data)
 556{
 557	__u32 tmp;
 558
 559	if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 560		return -EIO;
 561
 562	tmp = __peek_user_compat(child, addr);
 563	return put_user(tmp, (__u32 __user *) data);
 564}
 565
 566/*
 567 * Same as poke_user_per but for a 31 bit program.
 568 */
 569static inline void __poke_user_per_compat(struct task_struct *child,
 570					  addr_t addr, __u32 data)
 571{
 572	struct compat_per_struct_kernel *dummy32 = NULL;
 573
 574	if (addr == (addr_t) &dummy32->cr9)
 575		/* PER event mask of the user specified per set. */
 576		child->thread.per_user.control =
 577			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 578	else if (addr == (addr_t) &dummy32->starting_addr)
 579		/* Starting address of the user specified per set. */
 580		child->thread.per_user.start = data;
 581	else if (addr == (addr_t) &dummy32->ending_addr)
 582		/* Ending address of the user specified per set. */
 583		child->thread.per_user.end = data;
 584}
 585
 586/*
 587 * Same as poke_user but for a 31 bit program.
 588 */
 589static int __poke_user_compat(struct task_struct *child,
 590			      addr_t addr, addr_t data)
 591{
 592	struct compat_user *dummy32 = NULL;
 593	__u32 tmp = (__u32) data;
 594	addr_t offset;
 595
 596	if (addr < (addr_t) &dummy32->regs.acrs) {
 
 597		/*
 598		 * psw, gprs, acrs and orig_gpr2 are stored on the stack
 599		 */
 600		if (addr == (addr_t) &dummy32->regs.psw.mask) {
 601			/* Build a 64 bit psw mask from 31 bit mask. */
 602			if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
 603				/* Invalid psw mask. */
 604				return -EINVAL;
 605			task_pt_regs(child)->psw.mask =
 606				PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
 
 607		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 608			/* Build a 64 bit psw address from 31 bit address. */
 609			task_pt_regs(child)->psw.addr =
 610				(__u64) tmp & PSW32_ADDR_INSN;
 
 
 611		} else {
 612			/* gpr 0-15 */
 613			*(__u32*)((addr_t) &task_pt_regs(child)->psw
 614				  + addr*2 + 4) = tmp;
 615		}
 616	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 617		/*
 618		 * access registers are stored in the thread structure
 619		 */
 620		offset = addr - (addr_t) &dummy32->regs.acrs;
 621		*(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 622
 623	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 624		/*
 625		 * orig_gpr2 is stored on the kernel stack
 626		 */
 627		*(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 628
 629	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 630		/*
 631		 * prevent writess of padding hole between
 632		 * orig_gpr2 and fp_regs on s390.
 633		 */
 634		return 0;
 635
 636	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 637		/*
 638		 * floating point regs. are stored in the thread structure 
 639		 */
 640		if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
 641		    (tmp & ~FPC_VALID_MASK) != 0)
 642			/* Invalid floating point control. */
 643			return -EINVAL;
 644	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
 645		*(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
 646
 647	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 648		/*
 649		 * Handle access to the per_info structure.
 650		 */
 651		addr -= (addr_t) &dummy32->regs.per_info;
 652		__poke_user_per_compat(child, addr, data);
 653	}
 654
 655	return 0;
 656}
 657
 658static int poke_user_compat(struct task_struct *child,
 659			    addr_t addr, addr_t data)
 660{
 661	if (!is_compat_task() || (addr & 3) ||
 662	    addr > sizeof(struct compat_user) - 3)
 663		return -EIO;
 664
 665	return __poke_user_compat(child, addr, data);
 666}
 667
 668long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 669			compat_ulong_t caddr, compat_ulong_t cdata)
 670{
 671	unsigned long addr = caddr;
 672	unsigned long data = cdata;
 673	compat_ptrace_area parea;
 674	int copied, ret;
 675
 676	switch (request) {
 677	case PTRACE_PEEKUSR:
 678		/* read the word at location addr in the USER area. */
 679		return peek_user_compat(child, addr, data);
 680
 681	case PTRACE_POKEUSR:
 682		/* write the word at location addr in the USER area */
 683		return poke_user_compat(child, addr, data);
 684
 685	case PTRACE_PEEKUSR_AREA:
 686	case PTRACE_POKEUSR_AREA:
 687		if (copy_from_user(&parea, (void __force __user *) addr,
 688							sizeof(parea)))
 689			return -EFAULT;
 690		addr = parea.kernel_addr;
 691		data = parea.process_addr;
 692		copied = 0;
 693		while (copied < parea.len) {
 694			if (request == PTRACE_PEEKUSR_AREA)
 695				ret = peek_user_compat(child, addr, data);
 696			else {
 697				__u32 utmp;
 698				if (get_user(utmp,
 699					     (__u32 __force __user *) data))
 700					return -EFAULT;
 701				ret = poke_user_compat(child, addr, utmp);
 702			}
 703			if (ret)
 704				return ret;
 705			addr += sizeof(unsigned int);
 706			data += sizeof(unsigned int);
 707			copied += sizeof(unsigned int);
 708		}
 709		return 0;
 710	case PTRACE_GET_LAST_BREAK:
 711		put_user(task_thread_info(child)->last_break,
 712			 (unsigned int __user *) data);
 713		return 0;
 714	}
 715	return compat_ptrace_request(child, request, addr, data);
 716}
 717#endif
 718
 719asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 720{
 721	long ret = 0;
 722
 723	/* Do the secure computing check first. */
 724	secure_computing(regs->gprs[2]);
 725
 726	/*
 727	 * The sysc_tracesys code in entry.S stored the system
 728	 * call number to gprs[2].
 729	 */
 730	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 731	    (tracehook_report_syscall_entry(regs) ||
 732	     regs->gprs[2] >= NR_syscalls)) {
 733		/*
 734		 * Tracing decided this syscall should not happen or the
 735		 * debugger stored an invalid system call number. Skip
 736		 * the system call and the system call restart handling.
 737		 */
 738		regs->svcnr = 0;
 739		ret = -1;
 740	}
 741
 742	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 743		trace_sys_enter(regs, regs->gprs[2]);
 744
 745	if (unlikely(current->audit_context))
 746		audit_syscall_entry(is_compat_task() ?
 747					AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
 748				    regs->gprs[2], regs->orig_gpr2,
 749				    regs->gprs[3], regs->gprs[4],
 750				    regs->gprs[5]);
 751	return ret ?: regs->gprs[2];
 752}
 753
 754asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 755{
 756	if (unlikely(current->audit_context))
 757		audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
 758				   regs->gprs[2]);
 759
 760	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 761		trace_sys_exit(regs, regs->gprs[2]);
 762
 763	if (test_thread_flag(TIF_SYSCALL_TRACE))
 764		tracehook_report_syscall_exit(regs, 0);
 765}
 766
 767/*
 768 * user_regset definitions.
 769 */
 770
 771static int s390_regs_get(struct task_struct *target,
 772			 const struct user_regset *regset,
 773			 unsigned int pos, unsigned int count,
 774			 void *kbuf, void __user *ubuf)
 775{
 776	if (target == current)
 777		save_access_regs(target->thread.acrs);
 778
 779	if (kbuf) {
 780		unsigned long *k = kbuf;
 781		while (count > 0) {
 782			*k++ = __peek_user(target, pos);
 783			count -= sizeof(*k);
 784			pos += sizeof(*k);
 785		}
 786	} else {
 787		unsigned long __user *u = ubuf;
 788		while (count > 0) {
 789			if (__put_user(__peek_user(target, pos), u++))
 790				return -EFAULT;
 791			count -= sizeof(*u);
 792			pos += sizeof(*u);
 793		}
 794	}
 795	return 0;
 796}
 797
 798static int s390_regs_set(struct task_struct *target,
 799			 const struct user_regset *regset,
 800			 unsigned int pos, unsigned int count,
 801			 const void *kbuf, const void __user *ubuf)
 802{
 803	int rc = 0;
 804
 805	if (target == current)
 806		save_access_regs(target->thread.acrs);
 807
 808	if (kbuf) {
 809		const unsigned long *k = kbuf;
 810		while (count > 0 && !rc) {
 811			rc = __poke_user(target, pos, *k++);
 812			count -= sizeof(*k);
 813			pos += sizeof(*k);
 814		}
 815	} else {
 816		const unsigned long  __user *u = ubuf;
 817		while (count > 0 && !rc) {
 818			unsigned long word;
 819			rc = __get_user(word, u++);
 820			if (rc)
 821				break;
 822			rc = __poke_user(target, pos, word);
 823			count -= sizeof(*u);
 824			pos += sizeof(*u);
 825		}
 826	}
 827
 828	if (rc == 0 && target == current)
 829		restore_access_regs(target->thread.acrs);
 830
 831	return rc;
 832}
 833
 834static int s390_fpregs_get(struct task_struct *target,
 835			   const struct user_regset *regset, unsigned int pos,
 836			   unsigned int count, void *kbuf, void __user *ubuf)
 837{
 838	if (target == current)
 839		save_fp_regs(&target->thread.fp_regs);
 840
 841	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 842				   &target->thread.fp_regs, 0, -1);
 843}
 844
 845static int s390_fpregs_set(struct task_struct *target,
 846			   const struct user_regset *regset, unsigned int pos,
 847			   unsigned int count, const void *kbuf,
 848			   const void __user *ubuf)
 849{
 850	int rc = 0;
 851
 852	if (target == current)
 853		save_fp_regs(&target->thread.fp_regs);
 854
 855	/* If setting FPC, must validate it first. */
 856	if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 857		u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
 858		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
 859					0, offsetof(s390_fp_regs, fprs));
 860		if (rc)
 861			return rc;
 862		if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
 863			return -EINVAL;
 864		target->thread.fp_regs.fpc = fpc[0];
 865	}
 866
 867	if (rc == 0 && count > 0)
 868		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 869					target->thread.fp_regs.fprs,
 870					offsetof(s390_fp_regs, fprs), -1);
 871
 872	if (rc == 0 && target == current)
 873		restore_fp_regs(&target->thread.fp_regs);
 874
 875	return rc;
 876}
 877
 878#ifdef CONFIG_64BIT
 879
 880static int s390_last_break_get(struct task_struct *target,
 881			       const struct user_regset *regset,
 882			       unsigned int pos, unsigned int count,
 883			       void *kbuf, void __user *ubuf)
 884{
 885	if (count > 0) {
 886		if (kbuf) {
 887			unsigned long *k = kbuf;
 888			*k = task_thread_info(target)->last_break;
 889		} else {
 890			unsigned long  __user *u = ubuf;
 891			if (__put_user(task_thread_info(target)->last_break, u))
 892				return -EFAULT;
 893		}
 894	}
 895	return 0;
 896}
 897
 
 
 
 
 
 
 
 
 898#endif
 899
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 900static const struct user_regset s390_regsets[] = {
 901	[REGSET_GENERAL] = {
 902		.core_note_type = NT_PRSTATUS,
 903		.n = sizeof(s390_regs) / sizeof(long),
 904		.size = sizeof(long),
 905		.align = sizeof(long),
 906		.get = s390_regs_get,
 907		.set = s390_regs_set,
 908	},
 909	[REGSET_FP] = {
 910		.core_note_type = NT_PRFPREG,
 911		.n = sizeof(s390_fp_regs) / sizeof(long),
 912		.size = sizeof(long),
 913		.align = sizeof(long),
 914		.get = s390_fpregs_get,
 915		.set = s390_fpregs_set,
 916	},
 917#ifdef CONFIG_64BIT
 918	[REGSET_LAST_BREAK] = {
 919		.core_note_type = NT_S390_LAST_BREAK,
 920		.n = 1,
 921		.size = sizeof(long),
 922		.align = sizeof(long),
 923		.get = s390_last_break_get,
 
 924	},
 925#endif
 
 
 
 
 
 
 
 
 926};
 927
 928static const struct user_regset_view user_s390_view = {
 929	.name = UTS_MACHINE,
 930	.e_machine = EM_S390,
 931	.regsets = s390_regsets,
 932	.n = ARRAY_SIZE(s390_regsets)
 933};
 934
 935#ifdef CONFIG_COMPAT
 936static int s390_compat_regs_get(struct task_struct *target,
 937				const struct user_regset *regset,
 938				unsigned int pos, unsigned int count,
 939				void *kbuf, void __user *ubuf)
 940{
 941	if (target == current)
 942		save_access_regs(target->thread.acrs);
 943
 944	if (kbuf) {
 945		compat_ulong_t *k = kbuf;
 946		while (count > 0) {
 947			*k++ = __peek_user_compat(target, pos);
 948			count -= sizeof(*k);
 949			pos += sizeof(*k);
 950		}
 951	} else {
 952		compat_ulong_t __user *u = ubuf;
 953		while (count > 0) {
 954			if (__put_user(__peek_user_compat(target, pos), u++))
 955				return -EFAULT;
 956			count -= sizeof(*u);
 957			pos += sizeof(*u);
 958		}
 959	}
 960	return 0;
 961}
 962
 963static int s390_compat_regs_set(struct task_struct *target,
 964				const struct user_regset *regset,
 965				unsigned int pos, unsigned int count,
 966				const void *kbuf, const void __user *ubuf)
 967{
 968	int rc = 0;
 969
 970	if (target == current)
 971		save_access_regs(target->thread.acrs);
 972
 973	if (kbuf) {
 974		const compat_ulong_t *k = kbuf;
 975		while (count > 0 && !rc) {
 976			rc = __poke_user_compat(target, pos, *k++);
 977			count -= sizeof(*k);
 978			pos += sizeof(*k);
 979		}
 980	} else {
 981		const compat_ulong_t  __user *u = ubuf;
 982		while (count > 0 && !rc) {
 983			compat_ulong_t word;
 984			rc = __get_user(word, u++);
 985			if (rc)
 986				break;
 987			rc = __poke_user_compat(target, pos, word);
 988			count -= sizeof(*u);
 989			pos += sizeof(*u);
 990		}
 991	}
 992
 993	if (rc == 0 && target == current)
 994		restore_access_regs(target->thread.acrs);
 995
 996	return rc;
 997}
 998
 999static int s390_compat_regs_high_get(struct task_struct *target,
1000				     const struct user_regset *regset,
1001				     unsigned int pos, unsigned int count,
1002				     void *kbuf, void __user *ubuf)
1003{
1004	compat_ulong_t *gprs_high;
1005
1006	gprs_high = (compat_ulong_t *)
1007		&task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1008	if (kbuf) {
1009		compat_ulong_t *k = kbuf;
1010		while (count > 0) {
1011			*k++ = *gprs_high;
1012			gprs_high += 2;
1013			count -= sizeof(*k);
1014		}
1015	} else {
1016		compat_ulong_t __user *u = ubuf;
1017		while (count > 0) {
1018			if (__put_user(*gprs_high, u++))
1019				return -EFAULT;
1020			gprs_high += 2;
1021			count -= sizeof(*u);
1022		}
1023	}
1024	return 0;
1025}
1026
1027static int s390_compat_regs_high_set(struct task_struct *target,
1028				     const struct user_regset *regset,
1029				     unsigned int pos, unsigned int count,
1030				     const void *kbuf, const void __user *ubuf)
1031{
1032	compat_ulong_t *gprs_high;
1033	int rc = 0;
1034
1035	gprs_high = (compat_ulong_t *)
1036		&task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1037	if (kbuf) {
1038		const compat_ulong_t *k = kbuf;
1039		while (count > 0) {
1040			*gprs_high = *k++;
1041			*gprs_high += 2;
1042			count -= sizeof(*k);
1043		}
1044	} else {
1045		const compat_ulong_t  __user *u = ubuf;
1046		while (count > 0 && !rc) {
1047			unsigned long word;
1048			rc = __get_user(word, u++);
1049			if (rc)
1050				break;
1051			*gprs_high = word;
1052			*gprs_high += 2;
1053			count -= sizeof(*u);
1054		}
1055	}
1056
1057	return rc;
1058}
1059
1060static int s390_compat_last_break_get(struct task_struct *target,
1061				      const struct user_regset *regset,
1062				      unsigned int pos, unsigned int count,
1063				      void *kbuf, void __user *ubuf)
1064{
1065	compat_ulong_t last_break;
1066
1067	if (count > 0) {
1068		last_break = task_thread_info(target)->last_break;
1069		if (kbuf) {
1070			unsigned long *k = kbuf;
1071			*k = last_break;
1072		} else {
1073			unsigned long  __user *u = ubuf;
1074			if (__put_user(last_break, u))
1075				return -EFAULT;
1076		}
1077	}
1078	return 0;
1079}
1080
 
 
 
 
 
 
 
 
1081static const struct user_regset s390_compat_regsets[] = {
1082	[REGSET_GENERAL] = {
1083		.core_note_type = NT_PRSTATUS,
1084		.n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1085		.size = sizeof(compat_long_t),
1086		.align = sizeof(compat_long_t),
1087		.get = s390_compat_regs_get,
1088		.set = s390_compat_regs_set,
1089	},
1090	[REGSET_FP] = {
1091		.core_note_type = NT_PRFPREG,
1092		.n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1093		.size = sizeof(compat_long_t),
1094		.align = sizeof(compat_long_t),
1095		.get = s390_fpregs_get,
1096		.set = s390_fpregs_set,
1097	},
1098	[REGSET_LAST_BREAK] = {
1099		.core_note_type = NT_S390_LAST_BREAK,
1100		.n = 1,
1101		.size = sizeof(long),
1102		.align = sizeof(long),
1103		.get = s390_compat_last_break_get,
 
 
 
 
 
 
 
 
 
1104	},
1105	[REGSET_GENERAL_EXTENDED] = {
1106		.core_note_type = NT_S390_HIGH_GPRS,
1107		.n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1108		.size = sizeof(compat_long_t),
1109		.align = sizeof(compat_long_t),
1110		.get = s390_compat_regs_high_get,
1111		.set = s390_compat_regs_high_set,
1112	},
1113};
1114
1115static const struct user_regset_view user_s390_compat_view = {
1116	.name = "s390",
1117	.e_machine = EM_S390,
1118	.regsets = s390_compat_regsets,
1119	.n = ARRAY_SIZE(s390_compat_regsets)
1120};
1121#endif
1122
1123const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1124{
1125#ifdef CONFIG_COMPAT
1126	if (test_tsk_thread_flag(task, TIF_31BIT))
1127		return &user_s390_compat_view;
1128#endif
1129	return &user_s390_view;
1130}
1131
1132static const char *gpr_names[NUM_GPRS] = {
1133	"r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1134	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1135};
1136
1137unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1138{
1139	if (offset >= NUM_GPRS)
1140		return 0;
1141	return regs->gprs[offset];
1142}
1143
1144int regs_query_register_offset(const char *name)
1145{
1146	unsigned long offset;
1147
1148	if (!name || *name != 'r')
1149		return -EINVAL;
1150	if (strict_strtoul(name + 1, 10, &offset))
1151		return -EINVAL;
1152	if (offset >= NUM_GPRS)
1153		return -EINVAL;
1154	return offset;
1155}
1156
1157const char *regs_query_register_name(unsigned int offset)
1158{
1159	if (offset >= NUM_GPRS)
1160		return NULL;
1161	return gpr_names[offset];
1162}
1163
1164static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1165{
1166	unsigned long ksp = kernel_stack_pointer(regs);
1167
1168	return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1169}
1170
1171/**
1172 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1173 * @regs:pt_regs which contains kernel stack pointer.
1174 * @n:stack entry number.
1175 *
1176 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1177 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1178 * this returns 0.
1179 */
1180unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1181{
1182	unsigned long addr;
1183
1184	addr = kernel_stack_pointer(regs) + n * sizeof(long);
1185	if (!regs_within_kernel_stack(regs, addr))
1186		return 0;
1187	return *(unsigned long *)addr;
1188}
v3.5.6
   1/*
   2 *  Ptrace user space interface.
   3 *
   4 *    Copyright IBM Corp. 1999,2010
   5 *    Author(s): Denis Joseph Barrow
   6 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/sched.h>
  11#include <linux/mm.h>
  12#include <linux/smp.h>
  13#include <linux/errno.h>
  14#include <linux/ptrace.h>
  15#include <linux/user.h>
  16#include <linux/security.h>
  17#include <linux/audit.h>
  18#include <linux/signal.h>
  19#include <linux/elf.h>
  20#include <linux/regset.h>
  21#include <linux/tracehook.h>
  22#include <linux/seccomp.h>
  23#include <linux/compat.h>
  24#include <trace/syscall.h>
 
  25#include <asm/segment.h>
  26#include <asm/page.h>
  27#include <asm/pgtable.h>
  28#include <asm/pgalloc.h>
 
  29#include <asm/uaccess.h>
  30#include <asm/unistd.h>
  31#include <asm/switch_to.h>
  32#include "entry.h"
  33
  34#ifdef CONFIG_COMPAT
  35#include "compat_ptrace.h"
  36#endif
  37
  38#define CREATE_TRACE_POINTS
  39#include <trace/events/syscalls.h>
  40
  41enum s390_regset {
  42	REGSET_GENERAL,
  43	REGSET_FP,
  44	REGSET_LAST_BREAK,
  45	REGSET_SYSTEM_CALL,
  46	REGSET_GENERAL_EXTENDED,
  47};
  48
  49void update_per_regs(struct task_struct *task)
  50{
 
 
 
 
 
  51	struct pt_regs *regs = task_pt_regs(task);
  52	struct thread_struct *thread = &task->thread;
  53	struct per_regs old, new;
 
  54
  55	/* Copy user specified PER registers */
  56	new.control = thread->per_user.control;
  57	new.start = thread->per_user.start;
  58	new.end = thread->per_user.end;
  59
  60	/* merge TIF_SINGLE_STEP into user specified PER registers. */
  61	if (test_tsk_thread_flag(task, TIF_SINGLE_STEP)) {
  62		new.control |= PER_EVENT_IFETCH;
  63		new.start = 0;
  64		new.end = PSW_ADDR_INSN;
  65	}
  66
  67	/* Take care of the PER enablement bit in the PSW. */
  68	if (!(new.control & PER_EVENT_MASK)) {
  69		regs->psw.mask &= ~PSW_MASK_PER;
  70		return;
  71	}
  72	regs->psw.mask |= PSW_MASK_PER;
  73	__ctl_store(old, 9, 11);
  74	if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
  75		__ctl_load(new, 9, 11);
  76}
  77
  78void user_enable_single_step(struct task_struct *task)
  79{
  80	set_tsk_thread_flag(task, TIF_SINGLE_STEP);
  81	if (task == current)
  82		update_per_regs(task);
  83}
  84
  85void user_disable_single_step(struct task_struct *task)
  86{
  87	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
  88	if (task == current)
  89		update_per_regs(task);
  90}
  91
  92/*
  93 * Called by kernel/ptrace.c when detaching..
  94 *
  95 * Clear all debugging related fields.
  96 */
  97void ptrace_disable(struct task_struct *task)
  98{
  99	memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
 100	memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
 101	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
 102	clear_tsk_thread_flag(task, TIF_PER_TRAP);
 103}
 104
 105#ifndef CONFIG_64BIT
 106# define __ADDR_MASK 3
 107#else
 108# define __ADDR_MASK 7
 109#endif
 110
 111static inline unsigned long __peek_user_per(struct task_struct *child,
 112					    addr_t addr)
 113{
 114	struct per_struct_kernel *dummy = NULL;
 115
 116	if (addr == (addr_t) &dummy->cr9)
 117		/* Control bits of the active per set. */
 118		return test_thread_flag(TIF_SINGLE_STEP) ?
 119			PER_EVENT_IFETCH : child->thread.per_user.control;
 120	else if (addr == (addr_t) &dummy->cr10)
 121		/* Start address of the active per set. */
 122		return test_thread_flag(TIF_SINGLE_STEP) ?
 123			0 : child->thread.per_user.start;
 124	else if (addr == (addr_t) &dummy->cr11)
 125		/* End address of the active per set. */
 126		return test_thread_flag(TIF_SINGLE_STEP) ?
 127			PSW_ADDR_INSN : child->thread.per_user.end;
 128	else if (addr == (addr_t) &dummy->bits)
 129		/* Single-step bit. */
 130		return test_thread_flag(TIF_SINGLE_STEP) ?
 131			(1UL << (BITS_PER_LONG - 1)) : 0;
 132	else if (addr == (addr_t) &dummy->starting_addr)
 133		/* Start address of the user specified per set. */
 134		return child->thread.per_user.start;
 135	else if (addr == (addr_t) &dummy->ending_addr)
 136		/* End address of the user specified per set. */
 137		return child->thread.per_user.end;
 138	else if (addr == (addr_t) &dummy->perc_atmid)
 139		/* PER code, ATMID and AI of the last PER trap */
 140		return (unsigned long)
 141			child->thread.per_event.cause << (BITS_PER_LONG - 16);
 142	else if (addr == (addr_t) &dummy->address)
 143		/* Address of the last PER trap */
 144		return child->thread.per_event.address;
 145	else if (addr == (addr_t) &dummy->access_id)
 146		/* Access id of the last PER trap */
 147		return (unsigned long)
 148			child->thread.per_event.paid << (BITS_PER_LONG - 8);
 149	return 0;
 150}
 151
 152/*
 153 * Read the word at offset addr from the user area of a process. The
 154 * trouble here is that the information is littered over different
 155 * locations. The process registers are found on the kernel stack,
 156 * the floating point stuff and the trace settings are stored in
 157 * the task structure. In addition the different structures in
 158 * struct user contain pad bytes that should be read as zeroes.
 159 * Lovely...
 160 */
 161static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 162{
 163	struct user *dummy = NULL;
 164	addr_t offset, tmp;
 165
 166	if (addr < (addr_t) &dummy->regs.acrs) {
 167		/*
 168		 * psw and gprs are stored on the stack
 169		 */
 170		tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 171		if (addr == (addr_t) &dummy->regs.psw.mask)
 172			/* Return a clean psw mask. */
 173			tmp = psw_user_bits | (tmp & PSW_MASK_USER);
 174
 175	} else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 176		/*
 177		 * access registers are stored in the thread structure
 178		 */
 179		offset = addr - (addr_t) &dummy->regs.acrs;
 180#ifdef CONFIG_64BIT
 181		/*
 182		 * Very special case: old & broken 64 bit gdb reading
 183		 * from acrs[15]. Result is a 64 bit value. Read the
 184		 * 32 bit acrs[15] value and shift it by 32. Sick...
 185		 */
 186		if (addr == (addr_t) &dummy->regs.acrs[15])
 187			tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 188		else
 189#endif
 190		tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 191
 192	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 193		/*
 194		 * orig_gpr2 is stored on the kernel stack
 195		 */
 196		tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 197
 198	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
 199		/*
 200		 * prevent reads of padding hole between
 201		 * orig_gpr2 and fp_regs on s390.
 202		 */
 203		tmp = 0;
 204
 205	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 206		/* 
 207		 * floating point regs. are stored in the thread structure
 208		 */
 209		offset = addr - (addr_t) &dummy->regs.fp_regs;
 210		tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
 211		if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
 212			tmp &= (unsigned long) FPC_VALID_MASK
 213				<< (BITS_PER_LONG - 32);
 214
 215	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 216		/*
 217		 * Handle access to the per_info structure.
 218		 */
 219		addr -= (addr_t) &dummy->regs.per_info;
 220		tmp = __peek_user_per(child, addr);
 221
 222	} else
 223		tmp = 0;
 224
 225	return tmp;
 226}
 227
 228static int
 229peek_user(struct task_struct *child, addr_t addr, addr_t data)
 230{
 231	addr_t tmp, mask;
 232
 233	/*
 234	 * Stupid gdb peeks/pokes the access registers in 64 bit with
 235	 * an alignment of 4. Programmers from hell...
 236	 */
 237	mask = __ADDR_MASK;
 238#ifdef CONFIG_64BIT
 239	if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 240	    addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 241		mask = 3;
 242#endif
 243	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 244		return -EIO;
 245
 246	tmp = __peek_user(child, addr);
 247	return put_user(tmp, (addr_t __user *) data);
 248}
 249
 250static inline void __poke_user_per(struct task_struct *child,
 251				   addr_t addr, addr_t data)
 252{
 253	struct per_struct_kernel *dummy = NULL;
 254
 255	/*
 256	 * There are only three fields in the per_info struct that the
 257	 * debugger user can write to.
 258	 * 1) cr9: the debugger wants to set a new PER event mask
 259	 * 2) starting_addr: the debugger wants to set a new starting
 260	 *    address to use with the PER event mask.
 261	 * 3) ending_addr: the debugger wants to set a new ending
 262	 *    address to use with the PER event mask.
 263	 * The user specified PER event mask and the start and end
 264	 * addresses are used only if single stepping is not in effect.
 265	 * Writes to any other field in per_info are ignored.
 266	 */
 267	if (addr == (addr_t) &dummy->cr9)
 268		/* PER event mask of the user specified per set. */
 269		child->thread.per_user.control =
 270			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 271	else if (addr == (addr_t) &dummy->starting_addr)
 272		/* Starting address of the user specified per set. */
 273		child->thread.per_user.start = data;
 274	else if (addr == (addr_t) &dummy->ending_addr)
 275		/* Ending address of the user specified per set. */
 276		child->thread.per_user.end = data;
 277}
 278
 279/*
 280 * Write a word to the user area of a process at location addr. This
 281 * operation does have an additional problem compared to peek_user.
 282 * Stores to the program status word and on the floating point
 283 * control register needs to get checked for validity.
 284 */
 285static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 286{
 287	struct user *dummy = NULL;
 288	addr_t offset;
 289
 290	if (addr < (addr_t) &dummy->regs.acrs) {
 291		/*
 292		 * psw and gprs are stored on the stack
 293		 */
 294		if (addr == (addr_t) &dummy->regs.psw.mask &&
 295		    ((data & ~PSW_MASK_USER) != psw_user_bits ||
 296		     ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))))
 
 
 297			/* Invalid psw mask. */
 298			return -EINVAL;
 
 
 
 
 
 
 299		*(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 300
 301	} else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 302		/*
 303		 * access registers are stored in the thread structure
 304		 */
 305		offset = addr - (addr_t) &dummy->regs.acrs;
 306#ifdef CONFIG_64BIT
 307		/*
 308		 * Very special case: old & broken 64 bit gdb writing
 309		 * to acrs[15] with a 64 bit value. Ignore the lower
 310		 * half of the value and write the upper 32 bit to
 311		 * acrs[15]. Sick...
 312		 */
 313		if (addr == (addr_t) &dummy->regs.acrs[15])
 314			child->thread.acrs[15] = (unsigned int) (data >> 32);
 315		else
 316#endif
 317		*(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 318
 319	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 320		/*
 321		 * orig_gpr2 is stored on the kernel stack
 322		 */
 323		task_pt_regs(child)->orig_gpr2 = data;
 324
 325	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
 326		/*
 327		 * prevent writes of padding hole between
 328		 * orig_gpr2 and fp_regs on s390.
 329		 */
 330		return 0;
 331
 332	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 333		/*
 334		 * floating point regs. are stored in the thread structure
 335		 */
 336		if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
 337		    (data & ~((unsigned long) FPC_VALID_MASK
 338			      << (BITS_PER_LONG - 32))) != 0)
 339			return -EINVAL;
 340		offset = addr - (addr_t) &dummy->regs.fp_regs;
 341		*(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
 342
 343	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 344		/*
 345		 * Handle access to the per_info structure.
 346		 */
 347		addr -= (addr_t) &dummy->regs.per_info;
 348		__poke_user_per(child, addr, data);
 349
 350	}
 351
 352	return 0;
 353}
 354
 355static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
 356{
 357	addr_t mask;
 358
 359	/*
 360	 * Stupid gdb peeks/pokes the access registers in 64 bit with
 361	 * an alignment of 4. Programmers from hell indeed...
 362	 */
 363	mask = __ADDR_MASK;
 364#ifdef CONFIG_64BIT
 365	if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 366	    addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 367		mask = 3;
 368#endif
 369	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 370		return -EIO;
 371
 372	return __poke_user(child, addr, data);
 373}
 374
 375long arch_ptrace(struct task_struct *child, long request,
 376		 unsigned long addr, unsigned long data)
 377{
 378	ptrace_area parea; 
 379	int copied, ret;
 380
 381	switch (request) {
 382	case PTRACE_PEEKUSR:
 383		/* read the word at location addr in the USER area. */
 384		return peek_user(child, addr, data);
 385
 386	case PTRACE_POKEUSR:
 387		/* write the word at location addr in the USER area */
 388		return poke_user(child, addr, data);
 389
 390	case PTRACE_PEEKUSR_AREA:
 391	case PTRACE_POKEUSR_AREA:
 392		if (copy_from_user(&parea, (void __force __user *) addr,
 393							sizeof(parea)))
 394			return -EFAULT;
 395		addr = parea.kernel_addr;
 396		data = parea.process_addr;
 397		copied = 0;
 398		while (copied < parea.len) {
 399			if (request == PTRACE_PEEKUSR_AREA)
 400				ret = peek_user(child, addr, data);
 401			else {
 402				addr_t utmp;
 403				if (get_user(utmp,
 404					     (addr_t __force __user *) data))
 405					return -EFAULT;
 406				ret = poke_user(child, addr, utmp);
 407			}
 408			if (ret)
 409				return ret;
 410			addr += sizeof(unsigned long);
 411			data += sizeof(unsigned long);
 412			copied += sizeof(unsigned long);
 413		}
 414		return 0;
 415	case PTRACE_GET_LAST_BREAK:
 416		put_user(task_thread_info(child)->last_break,
 417			 (unsigned long __user *) data);
 418		return 0;
 419	default:
 420		/* Removing high order bit from addr (only for 31 bit). */
 421		addr &= PSW_ADDR_INSN;
 422		return ptrace_request(child, request, addr, data);
 423	}
 424}
 425
 426#ifdef CONFIG_COMPAT
 427/*
 428 * Now the fun part starts... a 31 bit program running in the
 429 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 430 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 431 * to handle, the difference to the 64 bit versions of the requests
 432 * is that the access is done in multiples of 4 byte instead of
 433 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 434 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 435 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 436 * is a 31 bit program too, the content of struct user can be
 437 * emulated. A 31 bit program peeking into the struct user of
 438 * a 64 bit program is a no-no.
 439 */
 440
 441/*
 442 * Same as peek_user_per but for a 31 bit program.
 443 */
 444static inline __u32 __peek_user_per_compat(struct task_struct *child,
 445					   addr_t addr)
 446{
 447	struct compat_per_struct_kernel *dummy32 = NULL;
 448
 449	if (addr == (addr_t) &dummy32->cr9)
 450		/* Control bits of the active per set. */
 451		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 452			PER_EVENT_IFETCH : child->thread.per_user.control;
 453	else if (addr == (addr_t) &dummy32->cr10)
 454		/* Start address of the active per set. */
 455		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 456			0 : child->thread.per_user.start;
 457	else if (addr == (addr_t) &dummy32->cr11)
 458		/* End address of the active per set. */
 459		return test_thread_flag(TIF_SINGLE_STEP) ?
 460			PSW32_ADDR_INSN : child->thread.per_user.end;
 461	else if (addr == (addr_t) &dummy32->bits)
 462		/* Single-step bit. */
 463		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
 464			0x80000000 : 0;
 465	else if (addr == (addr_t) &dummy32->starting_addr)
 466		/* Start address of the user specified per set. */
 467		return (__u32) child->thread.per_user.start;
 468	else if (addr == (addr_t) &dummy32->ending_addr)
 469		/* End address of the user specified per set. */
 470		return (__u32) child->thread.per_user.end;
 471	else if (addr == (addr_t) &dummy32->perc_atmid)
 472		/* PER code, ATMID and AI of the last PER trap */
 473		return (__u32) child->thread.per_event.cause << 16;
 474	else if (addr == (addr_t) &dummy32->address)
 475		/* Address of the last PER trap */
 476		return (__u32) child->thread.per_event.address;
 477	else if (addr == (addr_t) &dummy32->access_id)
 478		/* Access id of the last PER trap */
 479		return (__u32) child->thread.per_event.paid << 24;
 480	return 0;
 481}
 482
 483/*
 484 * Same as peek_user but for a 31 bit program.
 485 */
 486static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 487{
 488	struct compat_user *dummy32 = NULL;
 489	addr_t offset;
 490	__u32 tmp;
 491
 492	if (addr < (addr_t) &dummy32->regs.acrs) {
 493		struct pt_regs *regs = task_pt_regs(child);
 494		/*
 495		 * psw and gprs are stored on the stack
 496		 */
 497		if (addr == (addr_t) &dummy32->regs.psw.mask) {
 498			/* Fake a 31 bit psw mask. */
 499			tmp = (__u32)(regs->psw.mask >> 32);
 500			tmp = psw32_user_bits | (tmp & PSW32_MASK_USER);
 501		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 502			/* Fake a 31 bit psw address. */
 503			tmp = (__u32) regs->psw.addr |
 504				(__u32)(regs->psw.mask & PSW_MASK_BA);
 505		} else {
 506			/* gpr 0-15 */
 507			tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
 
 508		}
 509	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 510		/*
 511		 * access registers are stored in the thread structure
 512		 */
 513		offset = addr - (addr_t) &dummy32->regs.acrs;
 514		tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 515
 516	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 517		/*
 518		 * orig_gpr2 is stored on the kernel stack
 519		 */
 520		tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 521
 522	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 523		/*
 524		 * prevent reads of padding hole between
 525		 * orig_gpr2 and fp_regs on s390.
 526		 */
 527		tmp = 0;
 528
 529	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 530		/*
 531		 * floating point regs. are stored in the thread structure 
 532		 */
 533	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
 534		tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
 535
 536	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 537		/*
 538		 * Handle access to the per_info structure.
 539		 */
 540		addr -= (addr_t) &dummy32->regs.per_info;
 541		tmp = __peek_user_per_compat(child, addr);
 542
 543	} else
 544		tmp = 0;
 545
 546	return tmp;
 547}
 548
 549static int peek_user_compat(struct task_struct *child,
 550			    addr_t addr, addr_t data)
 551{
 552	__u32 tmp;
 553
 554	if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 555		return -EIO;
 556
 557	tmp = __peek_user_compat(child, addr);
 558	return put_user(tmp, (__u32 __user *) data);
 559}
 560
 561/*
 562 * Same as poke_user_per but for a 31 bit program.
 563 */
 564static inline void __poke_user_per_compat(struct task_struct *child,
 565					  addr_t addr, __u32 data)
 566{
 567	struct compat_per_struct_kernel *dummy32 = NULL;
 568
 569	if (addr == (addr_t) &dummy32->cr9)
 570		/* PER event mask of the user specified per set. */
 571		child->thread.per_user.control =
 572			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
 573	else if (addr == (addr_t) &dummy32->starting_addr)
 574		/* Starting address of the user specified per set. */
 575		child->thread.per_user.start = data;
 576	else if (addr == (addr_t) &dummy32->ending_addr)
 577		/* Ending address of the user specified per set. */
 578		child->thread.per_user.end = data;
 579}
 580
 581/*
 582 * Same as poke_user but for a 31 bit program.
 583 */
 584static int __poke_user_compat(struct task_struct *child,
 585			      addr_t addr, addr_t data)
 586{
 587	struct compat_user *dummy32 = NULL;
 588	__u32 tmp = (__u32) data;
 589	addr_t offset;
 590
 591	if (addr < (addr_t) &dummy32->regs.acrs) {
 592		struct pt_regs *regs = task_pt_regs(child);
 593		/*
 594		 * psw, gprs, acrs and orig_gpr2 are stored on the stack
 595		 */
 596		if (addr == (addr_t) &dummy32->regs.psw.mask) {
 597			/* Build a 64 bit psw mask from 31 bit mask. */
 598			if ((tmp & ~PSW32_MASK_USER) != psw32_user_bits)
 599				/* Invalid psw mask. */
 600				return -EINVAL;
 601			regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
 602				(regs->psw.mask & PSW_MASK_BA) |
 603				(__u64)(tmp & PSW32_MASK_USER) << 32;
 604		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 605			/* Build a 64 bit psw address from 31 bit address. */
 606			regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
 607			/* Transfer 31 bit amode bit to psw mask. */
 608			regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
 609				(__u64)(tmp & PSW32_ADDR_AMODE);
 610		} else {
 611			/* gpr 0-15 */
 612			*(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
 
 613		}
 614	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 615		/*
 616		 * access registers are stored in the thread structure
 617		 */
 618		offset = addr - (addr_t) &dummy32->regs.acrs;
 619		*(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 620
 621	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 622		/*
 623		 * orig_gpr2 is stored on the kernel stack
 624		 */
 625		*(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 626
 627	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 628		/*
 629		 * prevent writess of padding hole between
 630		 * orig_gpr2 and fp_regs on s390.
 631		 */
 632		return 0;
 633
 634	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 635		/*
 636		 * floating point regs. are stored in the thread structure 
 637		 */
 638		if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
 639		    (tmp & ~FPC_VALID_MASK) != 0)
 640			/* Invalid floating point control. */
 641			return -EINVAL;
 642	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
 643		*(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
 644
 645	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 646		/*
 647		 * Handle access to the per_info structure.
 648		 */
 649		addr -= (addr_t) &dummy32->regs.per_info;
 650		__poke_user_per_compat(child, addr, data);
 651	}
 652
 653	return 0;
 654}
 655
 656static int poke_user_compat(struct task_struct *child,
 657			    addr_t addr, addr_t data)
 658{
 659	if (!is_compat_task() || (addr & 3) ||
 660	    addr > sizeof(struct compat_user) - 3)
 661		return -EIO;
 662
 663	return __poke_user_compat(child, addr, data);
 664}
 665
 666long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 667			compat_ulong_t caddr, compat_ulong_t cdata)
 668{
 669	unsigned long addr = caddr;
 670	unsigned long data = cdata;
 671	compat_ptrace_area parea;
 672	int copied, ret;
 673
 674	switch (request) {
 675	case PTRACE_PEEKUSR:
 676		/* read the word at location addr in the USER area. */
 677		return peek_user_compat(child, addr, data);
 678
 679	case PTRACE_POKEUSR:
 680		/* write the word at location addr in the USER area */
 681		return poke_user_compat(child, addr, data);
 682
 683	case PTRACE_PEEKUSR_AREA:
 684	case PTRACE_POKEUSR_AREA:
 685		if (copy_from_user(&parea, (void __force __user *) addr,
 686							sizeof(parea)))
 687			return -EFAULT;
 688		addr = parea.kernel_addr;
 689		data = parea.process_addr;
 690		copied = 0;
 691		while (copied < parea.len) {
 692			if (request == PTRACE_PEEKUSR_AREA)
 693				ret = peek_user_compat(child, addr, data);
 694			else {
 695				__u32 utmp;
 696				if (get_user(utmp,
 697					     (__u32 __force __user *) data))
 698					return -EFAULT;
 699				ret = poke_user_compat(child, addr, utmp);
 700			}
 701			if (ret)
 702				return ret;
 703			addr += sizeof(unsigned int);
 704			data += sizeof(unsigned int);
 705			copied += sizeof(unsigned int);
 706		}
 707		return 0;
 708	case PTRACE_GET_LAST_BREAK:
 709		put_user(task_thread_info(child)->last_break,
 710			 (unsigned int __user *) data);
 711		return 0;
 712	}
 713	return compat_ptrace_request(child, request, addr, data);
 714}
 715#endif
 716
 717asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 718{
 719	long ret = 0;
 720
 721	/* Do the secure computing check first. */
 722	secure_computing_strict(regs->gprs[2]);
 723
 724	/*
 725	 * The sysc_tracesys code in entry.S stored the system
 726	 * call number to gprs[2].
 727	 */
 728	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 729	    (tracehook_report_syscall_entry(regs) ||
 730	     regs->gprs[2] >= NR_syscalls)) {
 731		/*
 732		 * Tracing decided this syscall should not happen or the
 733		 * debugger stored an invalid system call number. Skip
 734		 * the system call and the system call restart handling.
 735		 */
 736		clear_thread_flag(TIF_SYSCALL);
 737		ret = -1;
 738	}
 739
 740	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 741		trace_sys_enter(regs, regs->gprs[2]);
 742
 743	audit_syscall_entry(is_compat_task() ?
 744				AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
 745			    regs->gprs[2], regs->orig_gpr2,
 746			    regs->gprs[3], regs->gprs[4],
 747			    regs->gprs[5]);
 
 748	return ret ?: regs->gprs[2];
 749}
 750
 751asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 752{
 753	audit_syscall_exit(regs);
 
 
 754
 755	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 756		trace_sys_exit(regs, regs->gprs[2]);
 757
 758	if (test_thread_flag(TIF_SYSCALL_TRACE))
 759		tracehook_report_syscall_exit(regs, 0);
 760}
 761
 762/*
 763 * user_regset definitions.
 764 */
 765
 766static int s390_regs_get(struct task_struct *target,
 767			 const struct user_regset *regset,
 768			 unsigned int pos, unsigned int count,
 769			 void *kbuf, void __user *ubuf)
 770{
 771	if (target == current)
 772		save_access_regs(target->thread.acrs);
 773
 774	if (kbuf) {
 775		unsigned long *k = kbuf;
 776		while (count > 0) {
 777			*k++ = __peek_user(target, pos);
 778			count -= sizeof(*k);
 779			pos += sizeof(*k);
 780		}
 781	} else {
 782		unsigned long __user *u = ubuf;
 783		while (count > 0) {
 784			if (__put_user(__peek_user(target, pos), u++))
 785				return -EFAULT;
 786			count -= sizeof(*u);
 787			pos += sizeof(*u);
 788		}
 789	}
 790	return 0;
 791}
 792
 793static int s390_regs_set(struct task_struct *target,
 794			 const struct user_regset *regset,
 795			 unsigned int pos, unsigned int count,
 796			 const void *kbuf, const void __user *ubuf)
 797{
 798	int rc = 0;
 799
 800	if (target == current)
 801		save_access_regs(target->thread.acrs);
 802
 803	if (kbuf) {
 804		const unsigned long *k = kbuf;
 805		while (count > 0 && !rc) {
 806			rc = __poke_user(target, pos, *k++);
 807			count -= sizeof(*k);
 808			pos += sizeof(*k);
 809		}
 810	} else {
 811		const unsigned long  __user *u = ubuf;
 812		while (count > 0 && !rc) {
 813			unsigned long word;
 814			rc = __get_user(word, u++);
 815			if (rc)
 816				break;
 817			rc = __poke_user(target, pos, word);
 818			count -= sizeof(*u);
 819			pos += sizeof(*u);
 820		}
 821	}
 822
 823	if (rc == 0 && target == current)
 824		restore_access_regs(target->thread.acrs);
 825
 826	return rc;
 827}
 828
 829static int s390_fpregs_get(struct task_struct *target,
 830			   const struct user_regset *regset, unsigned int pos,
 831			   unsigned int count, void *kbuf, void __user *ubuf)
 832{
 833	if (target == current)
 834		save_fp_regs(&target->thread.fp_regs);
 835
 836	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 837				   &target->thread.fp_regs, 0, -1);
 838}
 839
 840static int s390_fpregs_set(struct task_struct *target,
 841			   const struct user_regset *regset, unsigned int pos,
 842			   unsigned int count, const void *kbuf,
 843			   const void __user *ubuf)
 844{
 845	int rc = 0;
 846
 847	if (target == current)
 848		save_fp_regs(&target->thread.fp_regs);
 849
 850	/* If setting FPC, must validate it first. */
 851	if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 852		u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
 853		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
 854					0, offsetof(s390_fp_regs, fprs));
 855		if (rc)
 856			return rc;
 857		if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
 858			return -EINVAL;
 859		target->thread.fp_regs.fpc = fpc[0];
 860	}
 861
 862	if (rc == 0 && count > 0)
 863		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 864					target->thread.fp_regs.fprs,
 865					offsetof(s390_fp_regs, fprs), -1);
 866
 867	if (rc == 0 && target == current)
 868		restore_fp_regs(&target->thread.fp_regs);
 869
 870	return rc;
 871}
 872
 873#ifdef CONFIG_64BIT
 874
 875static int s390_last_break_get(struct task_struct *target,
 876			       const struct user_regset *regset,
 877			       unsigned int pos, unsigned int count,
 878			       void *kbuf, void __user *ubuf)
 879{
 880	if (count > 0) {
 881		if (kbuf) {
 882			unsigned long *k = kbuf;
 883			*k = task_thread_info(target)->last_break;
 884		} else {
 885			unsigned long  __user *u = ubuf;
 886			if (__put_user(task_thread_info(target)->last_break, u))
 887				return -EFAULT;
 888		}
 889	}
 890	return 0;
 891}
 892
 893static int s390_last_break_set(struct task_struct *target,
 894			       const struct user_regset *regset,
 895			       unsigned int pos, unsigned int count,
 896			       const void *kbuf, const void __user *ubuf)
 897{
 898	return 0;
 899}
 900
 901#endif
 902
 903static int s390_system_call_get(struct task_struct *target,
 904				const struct user_regset *regset,
 905				unsigned int pos, unsigned int count,
 906				void *kbuf, void __user *ubuf)
 907{
 908	unsigned int *data = &task_thread_info(target)->system_call;
 909	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 910				   data, 0, sizeof(unsigned int));
 911}
 912
 913static int s390_system_call_set(struct task_struct *target,
 914				const struct user_regset *regset,
 915				unsigned int pos, unsigned int count,
 916				const void *kbuf, const void __user *ubuf)
 917{
 918	unsigned int *data = &task_thread_info(target)->system_call;
 919	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 920				  data, 0, sizeof(unsigned int));
 921}
 922
 923static const struct user_regset s390_regsets[] = {
 924	[REGSET_GENERAL] = {
 925		.core_note_type = NT_PRSTATUS,
 926		.n = sizeof(s390_regs) / sizeof(long),
 927		.size = sizeof(long),
 928		.align = sizeof(long),
 929		.get = s390_regs_get,
 930		.set = s390_regs_set,
 931	},
 932	[REGSET_FP] = {
 933		.core_note_type = NT_PRFPREG,
 934		.n = sizeof(s390_fp_regs) / sizeof(long),
 935		.size = sizeof(long),
 936		.align = sizeof(long),
 937		.get = s390_fpregs_get,
 938		.set = s390_fpregs_set,
 939	},
 940#ifdef CONFIG_64BIT
 941	[REGSET_LAST_BREAK] = {
 942		.core_note_type = NT_S390_LAST_BREAK,
 943		.n = 1,
 944		.size = sizeof(long),
 945		.align = sizeof(long),
 946		.get = s390_last_break_get,
 947		.set = s390_last_break_set,
 948	},
 949#endif
 950	[REGSET_SYSTEM_CALL] = {
 951		.core_note_type = NT_S390_SYSTEM_CALL,
 952		.n = 1,
 953		.size = sizeof(unsigned int),
 954		.align = sizeof(unsigned int),
 955		.get = s390_system_call_get,
 956		.set = s390_system_call_set,
 957	},
 958};
 959
 960static const struct user_regset_view user_s390_view = {
 961	.name = UTS_MACHINE,
 962	.e_machine = EM_S390,
 963	.regsets = s390_regsets,
 964	.n = ARRAY_SIZE(s390_regsets)
 965};
 966
 967#ifdef CONFIG_COMPAT
 968static int s390_compat_regs_get(struct task_struct *target,
 969				const struct user_regset *regset,
 970				unsigned int pos, unsigned int count,
 971				void *kbuf, void __user *ubuf)
 972{
 973	if (target == current)
 974		save_access_regs(target->thread.acrs);
 975
 976	if (kbuf) {
 977		compat_ulong_t *k = kbuf;
 978		while (count > 0) {
 979			*k++ = __peek_user_compat(target, pos);
 980			count -= sizeof(*k);
 981			pos += sizeof(*k);
 982		}
 983	} else {
 984		compat_ulong_t __user *u = ubuf;
 985		while (count > 0) {
 986			if (__put_user(__peek_user_compat(target, pos), u++))
 987				return -EFAULT;
 988			count -= sizeof(*u);
 989			pos += sizeof(*u);
 990		}
 991	}
 992	return 0;
 993}
 994
 995static int s390_compat_regs_set(struct task_struct *target,
 996				const struct user_regset *regset,
 997				unsigned int pos, unsigned int count,
 998				const void *kbuf, const void __user *ubuf)
 999{
1000	int rc = 0;
1001
1002	if (target == current)
1003		save_access_regs(target->thread.acrs);
1004
1005	if (kbuf) {
1006		const compat_ulong_t *k = kbuf;
1007		while (count > 0 && !rc) {
1008			rc = __poke_user_compat(target, pos, *k++);
1009			count -= sizeof(*k);
1010			pos += sizeof(*k);
1011		}
1012	} else {
1013		const compat_ulong_t  __user *u = ubuf;
1014		while (count > 0 && !rc) {
1015			compat_ulong_t word;
1016			rc = __get_user(word, u++);
1017			if (rc)
1018				break;
1019			rc = __poke_user_compat(target, pos, word);
1020			count -= sizeof(*u);
1021			pos += sizeof(*u);
1022		}
1023	}
1024
1025	if (rc == 0 && target == current)
1026		restore_access_regs(target->thread.acrs);
1027
1028	return rc;
1029}
1030
1031static int s390_compat_regs_high_get(struct task_struct *target,
1032				     const struct user_regset *regset,
1033				     unsigned int pos, unsigned int count,
1034				     void *kbuf, void __user *ubuf)
1035{
1036	compat_ulong_t *gprs_high;
1037
1038	gprs_high = (compat_ulong_t *)
1039		&task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1040	if (kbuf) {
1041		compat_ulong_t *k = kbuf;
1042		while (count > 0) {
1043			*k++ = *gprs_high;
1044			gprs_high += 2;
1045			count -= sizeof(*k);
1046		}
1047	} else {
1048		compat_ulong_t __user *u = ubuf;
1049		while (count > 0) {
1050			if (__put_user(*gprs_high, u++))
1051				return -EFAULT;
1052			gprs_high += 2;
1053			count -= sizeof(*u);
1054		}
1055	}
1056	return 0;
1057}
1058
1059static int s390_compat_regs_high_set(struct task_struct *target,
1060				     const struct user_regset *regset,
1061				     unsigned int pos, unsigned int count,
1062				     const void *kbuf, const void __user *ubuf)
1063{
1064	compat_ulong_t *gprs_high;
1065	int rc = 0;
1066
1067	gprs_high = (compat_ulong_t *)
1068		&task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1069	if (kbuf) {
1070		const compat_ulong_t *k = kbuf;
1071		while (count > 0) {
1072			*gprs_high = *k++;
1073			*gprs_high += 2;
1074			count -= sizeof(*k);
1075		}
1076	} else {
1077		const compat_ulong_t  __user *u = ubuf;
1078		while (count > 0 && !rc) {
1079			unsigned long word;
1080			rc = __get_user(word, u++);
1081			if (rc)
1082				break;
1083			*gprs_high = word;
1084			*gprs_high += 2;
1085			count -= sizeof(*u);
1086		}
1087	}
1088
1089	return rc;
1090}
1091
1092static int s390_compat_last_break_get(struct task_struct *target,
1093				      const struct user_regset *regset,
1094				      unsigned int pos, unsigned int count,
1095				      void *kbuf, void __user *ubuf)
1096{
1097	compat_ulong_t last_break;
1098
1099	if (count > 0) {
1100		last_break = task_thread_info(target)->last_break;
1101		if (kbuf) {
1102			unsigned long *k = kbuf;
1103			*k = last_break;
1104		} else {
1105			unsigned long  __user *u = ubuf;
1106			if (__put_user(last_break, u))
1107				return -EFAULT;
1108		}
1109	}
1110	return 0;
1111}
1112
1113static int s390_compat_last_break_set(struct task_struct *target,
1114				      const struct user_regset *regset,
1115				      unsigned int pos, unsigned int count,
1116				      const void *kbuf, const void __user *ubuf)
1117{
1118	return 0;
1119}
1120
1121static const struct user_regset s390_compat_regsets[] = {
1122	[REGSET_GENERAL] = {
1123		.core_note_type = NT_PRSTATUS,
1124		.n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1125		.size = sizeof(compat_long_t),
1126		.align = sizeof(compat_long_t),
1127		.get = s390_compat_regs_get,
1128		.set = s390_compat_regs_set,
1129	},
1130	[REGSET_FP] = {
1131		.core_note_type = NT_PRFPREG,
1132		.n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1133		.size = sizeof(compat_long_t),
1134		.align = sizeof(compat_long_t),
1135		.get = s390_fpregs_get,
1136		.set = s390_fpregs_set,
1137	},
1138	[REGSET_LAST_BREAK] = {
1139		.core_note_type = NT_S390_LAST_BREAK,
1140		.n = 1,
1141		.size = sizeof(long),
1142		.align = sizeof(long),
1143		.get = s390_compat_last_break_get,
1144		.set = s390_compat_last_break_set,
1145	},
1146	[REGSET_SYSTEM_CALL] = {
1147		.core_note_type = NT_S390_SYSTEM_CALL,
1148		.n = 1,
1149		.size = sizeof(compat_uint_t),
1150		.align = sizeof(compat_uint_t),
1151		.get = s390_system_call_get,
1152		.set = s390_system_call_set,
1153	},
1154	[REGSET_GENERAL_EXTENDED] = {
1155		.core_note_type = NT_S390_HIGH_GPRS,
1156		.n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1157		.size = sizeof(compat_long_t),
1158		.align = sizeof(compat_long_t),
1159		.get = s390_compat_regs_high_get,
1160		.set = s390_compat_regs_high_set,
1161	},
1162};
1163
1164static const struct user_regset_view user_s390_compat_view = {
1165	.name = "s390",
1166	.e_machine = EM_S390,
1167	.regsets = s390_compat_regsets,
1168	.n = ARRAY_SIZE(s390_compat_regsets)
1169};
1170#endif
1171
1172const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1173{
1174#ifdef CONFIG_COMPAT
1175	if (test_tsk_thread_flag(task, TIF_31BIT))
1176		return &user_s390_compat_view;
1177#endif
1178	return &user_s390_view;
1179}
1180
1181static const char *gpr_names[NUM_GPRS] = {
1182	"r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1183	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1184};
1185
1186unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1187{
1188	if (offset >= NUM_GPRS)
1189		return 0;
1190	return regs->gprs[offset];
1191}
1192
1193int regs_query_register_offset(const char *name)
1194{
1195	unsigned long offset;
1196
1197	if (!name || *name != 'r')
1198		return -EINVAL;
1199	if (strict_strtoul(name + 1, 10, &offset))
1200		return -EINVAL;
1201	if (offset >= NUM_GPRS)
1202		return -EINVAL;
1203	return offset;
1204}
1205
1206const char *regs_query_register_name(unsigned int offset)
1207{
1208	if (offset >= NUM_GPRS)
1209		return NULL;
1210	return gpr_names[offset];
1211}
1212
1213static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1214{
1215	unsigned long ksp = kernel_stack_pointer(regs);
1216
1217	return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1218}
1219
1220/**
1221 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1222 * @regs:pt_regs which contains kernel stack pointer.
1223 * @n:stack entry number.
1224 *
1225 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1226 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1227 * this returns 0.
1228 */
1229unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1230{
1231	unsigned long addr;
1232
1233	addr = kernel_stack_pointer(regs) + n * sizeof(long);
1234	if (!regs_within_kernel_stack(regs, addr))
1235		return 0;
1236	return *(unsigned long *)addr;
1237}