Merge branch 'for-rmk' of git://pasiphae.extern.pengutronix.de/git/imx/linux-2.6.git
[linux-2.6] / arch / s390 / kernel / ptrace.c
1 /*
2  *  arch/s390/kernel/ptrace.c
3  *
4  *  S390 version
5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Based on PowerPC version 
10  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
11  *
12  *  Derived from "arch/m68k/kernel/ptrace.c"
13  *  Copyright (C) 1994 by Hamish Macdonald
14  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
15  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
16  *
17  * Modified by Cort Dougan (cort@cs.nmt.edu) 
18  *
19  *
20  * This file is subject to the terms and conditions of the GNU General
21  * Public License.  See the file README.legal in the main directory of
22  * this archive for more details.
23  */
24
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/mm.h>
28 #include <linux/smp.h>
29 #include <linux/smp_lock.h>
30 #include <linux/errno.h>
31 #include <linux/ptrace.h>
32 #include <linux/user.h>
33 #include <linux/security.h>
34 #include <linux/audit.h>
35 #include <linux/signal.h>
36 #include <linux/elf.h>
37 #include <linux/regset.h>
38
39 #include <asm/segment.h>
40 #include <asm/page.h>
41 #include <asm/pgtable.h>
42 #include <asm/pgalloc.h>
43 #include <asm/system.h>
44 #include <asm/uaccess.h>
45 #include <asm/unistd.h>
46 #include "entry.h"
47
48 #ifdef CONFIG_COMPAT
49 #include "compat_ptrace.h"
50 #endif
51
52 enum s390_regset {
53         REGSET_GENERAL,
54         REGSET_FP,
55 };
56
57 static void
58 FixPerRegisters(struct task_struct *task)
59 {
60         struct pt_regs *regs;
61         per_struct *per_info;
62
63         regs = task_pt_regs(task);
64         per_info = (per_struct *) &task->thread.per_info;
65         per_info->control_regs.bits.em_instruction_fetch =
66                 per_info->single_step | per_info->instruction_fetch;
67         
68         if (per_info->single_step) {
69                 per_info->control_regs.bits.starting_addr = 0;
70 #ifdef CONFIG_COMPAT
71                 if (test_thread_flag(TIF_31BIT))
72                         per_info->control_regs.bits.ending_addr = 0x7fffffffUL;
73                 else
74 #endif
75                         per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN;
76         } else {
77                 per_info->control_regs.bits.starting_addr =
78                         per_info->starting_addr;
79                 per_info->control_regs.bits.ending_addr =
80                         per_info->ending_addr;
81         }
82         /*
83          * if any of the control reg tracing bits are on 
84          * we switch on per in the psw
85          */
86         if (per_info->control_regs.words.cr[0] & PER_EM_MASK)
87                 regs->psw.mask |= PSW_MASK_PER;
88         else
89                 regs->psw.mask &= ~PSW_MASK_PER;
90
91         if (per_info->control_regs.bits.em_storage_alteration)
92                 per_info->control_regs.bits.storage_alt_space_ctl = 1;
93         else
94                 per_info->control_regs.bits.storage_alt_space_ctl = 0;
95 }
96
97 void user_enable_single_step(struct task_struct *task)
98 {
99         task->thread.per_info.single_step = 1;
100         FixPerRegisters(task);
101 }
102
103 void user_disable_single_step(struct task_struct *task)
104 {
105         task->thread.per_info.single_step = 0;
106         FixPerRegisters(task);
107 }
108
109 /*
110  * Called by kernel/ptrace.c when detaching..
111  *
112  * Make sure single step bits etc are not set.
113  */
114 void
115 ptrace_disable(struct task_struct *child)
116 {
117         /* make sure the single step bit is not set. */
118         user_disable_single_step(child);
119 }
120
121 #ifndef CONFIG_64BIT
122 # define __ADDR_MASK 3
123 #else
124 # define __ADDR_MASK 7
125 #endif
126
127 /*
128  * Read the word at offset addr from the user area of a process. The
129  * trouble here is that the information is littered over different
130  * locations. The process registers are found on the kernel stack,
131  * the floating point stuff and the trace settings are stored in
132  * the task structure. In addition the different structures in
133  * struct user contain pad bytes that should be read as zeroes.
134  * Lovely...
135  */
136 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
137 {
138         struct user *dummy = NULL;
139         addr_t offset, tmp;
140
141         if (addr < (addr_t) &dummy->regs.acrs) {
142                 /*
143                  * psw and gprs are stored on the stack
144                  */
145                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
146                 if (addr == (addr_t) &dummy->regs.psw.mask)
147                         /* Remove per bit from user psw. */
148                         tmp &= ~PSW_MASK_PER;
149
150         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
151                 /*
152                  * access registers are stored in the thread structure
153                  */
154                 offset = addr - (addr_t) &dummy->regs.acrs;
155 #ifdef CONFIG_64BIT
156                 /*
157                  * Very special case: old & broken 64 bit gdb reading
158                  * from acrs[15]. Result is a 64 bit value. Read the
159                  * 32 bit acrs[15] value and shift it by 32. Sick...
160                  */
161                 if (addr == (addr_t) &dummy->regs.acrs[15])
162                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
163                 else
164 #endif
165                 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
166
167         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
168                 /*
169                  * orig_gpr2 is stored on the kernel stack
170                  */
171                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
172
173         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
174                 /*
175                  * prevent reads of padding hole between
176                  * orig_gpr2 and fp_regs on s390.
177                  */
178                 tmp = 0;
179
180         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
181                 /* 
182                  * floating point regs. are stored in the thread structure
183                  */
184                 offset = addr - (addr_t) &dummy->regs.fp_regs;
185                 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
186                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
187                         tmp &= (unsigned long) FPC_VALID_MASK
188                                 << (BITS_PER_LONG - 32);
189
190         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
191                 /*
192                  * per_info is found in the thread structure
193                  */
194                 offset = addr - (addr_t) &dummy->regs.per_info;
195                 tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset);
196
197         } else
198                 tmp = 0;
199
200         return tmp;
201 }
202
203 static int
204 peek_user(struct task_struct *child, addr_t addr, addr_t data)
205 {
206         struct user *dummy = NULL;
207         addr_t tmp, mask;
208
209         /*
210          * Stupid gdb peeks/pokes the access registers in 64 bit with
211          * an alignment of 4. Programmers from hell...
212          */
213         mask = __ADDR_MASK;
214 #ifdef CONFIG_64BIT
215         if (addr >= (addr_t) &dummy->regs.acrs &&
216             addr < (addr_t) &dummy->regs.orig_gpr2)
217                 mask = 3;
218 #endif
219         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
220                 return -EIO;
221
222         tmp = __peek_user(child, addr);
223         return put_user(tmp, (addr_t __user *) data);
224 }
225
226 /*
227  * Write a word to the user area of a process at location addr. This
228  * operation does have an additional problem compared to peek_user.
229  * Stores to the program status word and on the floating point
230  * control register needs to get checked for validity.
231  */
232 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
233 {
234         struct user *dummy = NULL;
235         addr_t offset;
236
237         if (addr < (addr_t) &dummy->regs.acrs) {
238                 /*
239                  * psw and gprs are stored on the stack
240                  */
241                 if (addr == (addr_t) &dummy->regs.psw.mask &&
242 #ifdef CONFIG_COMPAT
243                     data != PSW_MASK_MERGE(psw_user32_bits, data) &&
244 #endif
245                     data != PSW_MASK_MERGE(psw_user_bits, data))
246                         /* Invalid psw mask. */
247                         return -EINVAL;
248 #ifndef CONFIG_64BIT
249                 if (addr == (addr_t) &dummy->regs.psw.addr)
250                         /* I'd like to reject addresses without the
251                            high order bit but older gdb's rely on it */
252                         data |= PSW_ADDR_AMODE;
253 #endif
254                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
255
256         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
257                 /*
258                  * access registers are stored in the thread structure
259                  */
260                 offset = addr - (addr_t) &dummy->regs.acrs;
261 #ifdef CONFIG_64BIT
262                 /*
263                  * Very special case: old & broken 64 bit gdb writing
264                  * to acrs[15] with a 64 bit value. Ignore the lower
265                  * half of the value and write the upper 32 bit to
266                  * acrs[15]. Sick...
267                  */
268                 if (addr == (addr_t) &dummy->regs.acrs[15])
269                         child->thread.acrs[15] = (unsigned int) (data >> 32);
270                 else
271 #endif
272                 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
273
274         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
275                 /*
276                  * orig_gpr2 is stored on the kernel stack
277                  */
278                 task_pt_regs(child)->orig_gpr2 = data;
279
280         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
281                 /*
282                  * prevent writes of padding hole between
283                  * orig_gpr2 and fp_regs on s390.
284                  */
285                 return 0;
286
287         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
288                 /*
289                  * floating point regs. are stored in the thread structure
290                  */
291                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
292                     (data & ~((unsigned long) FPC_VALID_MASK
293                               << (BITS_PER_LONG - 32))) != 0)
294                         return -EINVAL;
295                 offset = addr - (addr_t) &dummy->regs.fp_regs;
296                 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
297
298         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
299                 /*
300                  * per_info is found in the thread structure 
301                  */
302                 offset = addr - (addr_t) &dummy->regs.per_info;
303                 *(addr_t *)((addr_t) &child->thread.per_info + offset) = data;
304
305         }
306
307         FixPerRegisters(child);
308         return 0;
309 }
310
311 static int
312 poke_user(struct task_struct *child, addr_t addr, addr_t data)
313 {
314         struct user *dummy = NULL;
315         addr_t mask;
316
317         /*
318          * Stupid gdb peeks/pokes the access registers in 64 bit with
319          * an alignment of 4. Programmers from hell indeed...
320          */
321         mask = __ADDR_MASK;
322 #ifdef CONFIG_64BIT
323         if (addr >= (addr_t) &dummy->regs.acrs &&
324             addr < (addr_t) &dummy->regs.orig_gpr2)
325                 mask = 3;
326 #endif
327         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
328                 return -EIO;
329
330         return __poke_user(child, addr, data);
331 }
332
333 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
334 {
335         ptrace_area parea; 
336         int copied, ret;
337
338         switch (request) {
339         case PTRACE_PEEKTEXT:
340         case PTRACE_PEEKDATA:
341                 /* Remove high order bit from address (only for 31 bit). */
342                 addr &= PSW_ADDR_INSN;
343                 /* read word at location addr. */
344                 return generic_ptrace_peekdata(child, addr, data);
345
346         case PTRACE_PEEKUSR:
347                 /* read the word at location addr in the USER area. */
348                 return peek_user(child, addr, data);
349
350         case PTRACE_POKETEXT:
351         case PTRACE_POKEDATA:
352                 /* Remove high order bit from address (only for 31 bit). */
353                 addr &= PSW_ADDR_INSN;
354                 /* write the word at location addr. */
355                 return generic_ptrace_pokedata(child, addr, data);
356
357         case PTRACE_POKEUSR:
358                 /* write the word at location addr in the USER area */
359                 return poke_user(child, addr, data);
360
361         case PTRACE_PEEKUSR_AREA:
362         case PTRACE_POKEUSR_AREA:
363                 if (copy_from_user(&parea, (void __force __user *) addr,
364                                                         sizeof(parea)))
365                         return -EFAULT;
366                 addr = parea.kernel_addr;
367                 data = parea.process_addr;
368                 copied = 0;
369                 while (copied < parea.len) {
370                         if (request == PTRACE_PEEKUSR_AREA)
371                                 ret = peek_user(child, addr, data);
372                         else {
373                                 addr_t utmp;
374                                 if (get_user(utmp,
375                                              (addr_t __force __user *) data))
376                                         return -EFAULT;
377                                 ret = poke_user(child, addr, utmp);
378                         }
379                         if (ret)
380                                 return ret;
381                         addr += sizeof(unsigned long);
382                         data += sizeof(unsigned long);
383                         copied += sizeof(unsigned long);
384                 }
385                 return 0;
386         }
387         return ptrace_request(child, request, addr, data);
388 }
389
390 #ifdef CONFIG_COMPAT
391 /*
392  * Now the fun part starts... a 31 bit program running in the
393  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
394  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
395  * to handle, the difference to the 64 bit versions of the requests
396  * is that the access is done in multiples of 4 byte instead of
397  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
398  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
399  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
400  * is a 31 bit program too, the content of struct user can be
401  * emulated. A 31 bit program peeking into the struct user of
402  * a 64 bit program is a no-no.
403  */
404
405 /*
406  * Same as peek_user but for a 31 bit program.
407  */
408 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
409 {
410         struct user32 *dummy32 = NULL;
411         per_struct32 *dummy_per32 = NULL;
412         addr_t offset;
413         __u32 tmp;
414
415         if (addr < (addr_t) &dummy32->regs.acrs) {
416                 /*
417                  * psw and gprs are stored on the stack
418                  */
419                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
420                         /* Fake a 31 bit psw mask. */
421                         tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
422                         tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
423                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
424                         /* Fake a 31 bit psw address. */
425                         tmp = (__u32) task_pt_regs(child)->psw.addr |
426                                 PSW32_ADDR_AMODE31;
427                 } else {
428                         /* gpr 0-15 */
429                         tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
430                                          addr*2 + 4);
431                 }
432         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
433                 /*
434                  * access registers are stored in the thread structure
435                  */
436                 offset = addr - (addr_t) &dummy32->regs.acrs;
437                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
438
439         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
440                 /*
441                  * orig_gpr2 is stored on the kernel stack
442                  */
443                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
444
445         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
446                 /*
447                  * prevent reads of padding hole between
448                  * orig_gpr2 and fp_regs on s390.
449                  */
450                 tmp = 0;
451
452         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
453                 /*
454                  * floating point regs. are stored in the thread structure 
455                  */
456                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
457                 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
458
459         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
460                 /*
461                  * per_info is found in the thread structure
462                  */
463                 offset = addr - (addr_t) &dummy32->regs.per_info;
464                 /* This is magic. See per_struct and per_struct32. */
465                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
466                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
467                     (offset >= (addr_t) &dummy_per32->starting_addr &&
468                      offset <= (addr_t) &dummy_per32->ending_addr) ||
469                     offset == (addr_t) &dummy_per32->lowcore.words.address)
470                         offset = offset*2 + 4;
471                 else
472                         offset = offset*2;
473                 tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset);
474
475         } else
476                 tmp = 0;
477
478         return tmp;
479 }
480
481 static int peek_user_compat(struct task_struct *child,
482                             addr_t addr, addr_t data)
483 {
484         __u32 tmp;
485
486         if (!test_thread_flag(TIF_31BIT) ||
487             (addr & 3) || addr > sizeof(struct user) - 3)
488                 return -EIO;
489
490         tmp = __peek_user_compat(child, addr);
491         return put_user(tmp, (__u32 __user *) data);
492 }
493
494 /*
495  * Same as poke_user but for a 31 bit program.
496  */
497 static int __poke_user_compat(struct task_struct *child,
498                               addr_t addr, addr_t data)
499 {
500         struct user32 *dummy32 = NULL;
501         per_struct32 *dummy_per32 = NULL;
502         __u32 tmp = (__u32) data;
503         addr_t offset;
504
505         if (addr < (addr_t) &dummy32->regs.acrs) {
506                 /*
507                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
508                  */
509                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
510                         /* Build a 64 bit psw mask from 31 bit mask. */
511                         if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
512                                 /* Invalid psw mask. */
513                                 return -EINVAL;
514                         task_pt_regs(child)->psw.mask =
515                                 PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
516                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
517                         /* Build a 64 bit psw address from 31 bit address. */
518                         task_pt_regs(child)->psw.addr =
519                                 (__u64) tmp & PSW32_ADDR_INSN;
520                 } else {
521                         /* gpr 0-15 */
522                         *(__u32*)((addr_t) &task_pt_regs(child)->psw
523                                   + addr*2 + 4) = tmp;
524                 }
525         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
526                 /*
527                  * access registers are stored in the thread structure
528                  */
529                 offset = addr - (addr_t) &dummy32->regs.acrs;
530                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
531
532         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
533                 /*
534                  * orig_gpr2 is stored on the kernel stack
535                  */
536                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
537
538         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
539                 /*
540                  * prevent writess of padding hole between
541                  * orig_gpr2 and fp_regs on s390.
542                  */
543                 return 0;
544
545         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
546                 /*
547                  * floating point regs. are stored in the thread structure 
548                  */
549                 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
550                     (tmp & ~FPC_VALID_MASK) != 0)
551                         /* Invalid floating point control. */
552                         return -EINVAL;
553                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
554                 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
555
556         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
557                 /*
558                  * per_info is found in the thread structure.
559                  */
560                 offset = addr - (addr_t) &dummy32->regs.per_info;
561                 /*
562                  * This is magic. See per_struct and per_struct32.
563                  * By incident the offsets in per_struct are exactly
564                  * twice the offsets in per_struct32 for all fields.
565                  * The 8 byte fields need special handling though,
566                  * because the second half (bytes 4-7) is needed and
567                  * not the first half.
568                  */
569                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
570                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
571                     (offset >= (addr_t) &dummy_per32->starting_addr &&
572                      offset <= (addr_t) &dummy_per32->ending_addr) ||
573                     offset == (addr_t) &dummy_per32->lowcore.words.address)
574                         offset = offset*2 + 4;
575                 else
576                         offset = offset*2;
577                 *(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp;
578
579         }
580
581         FixPerRegisters(child);
582         return 0;
583 }
584
585 static int poke_user_compat(struct task_struct *child,
586                             addr_t addr, addr_t data)
587 {
588         if (!test_thread_flag(TIF_31BIT) ||
589             (addr & 3) || addr > sizeof(struct user32) - 3)
590                 return -EIO;
591
592         return __poke_user_compat(child, addr, data);
593 }
594
595 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
596                         compat_ulong_t caddr, compat_ulong_t cdata)
597 {
598         unsigned long addr = caddr;
599         unsigned long data = cdata;
600         ptrace_area_emu31 parea; 
601         int copied, ret;
602
603         switch (request) {
604         case PTRACE_PEEKUSR:
605                 /* read the word at location addr in the USER area. */
606                 return peek_user_compat(child, addr, data);
607
608         case PTRACE_POKEUSR:
609                 /* write the word at location addr in the USER area */
610                 return poke_user_compat(child, addr, data);
611
612         case PTRACE_PEEKUSR_AREA:
613         case PTRACE_POKEUSR_AREA:
614                 if (copy_from_user(&parea, (void __force __user *) addr,
615                                                         sizeof(parea)))
616                         return -EFAULT;
617                 addr = parea.kernel_addr;
618                 data = parea.process_addr;
619                 copied = 0;
620                 while (copied < parea.len) {
621                         if (request == PTRACE_PEEKUSR_AREA)
622                                 ret = peek_user_compat(child, addr, data);
623                         else {
624                                 __u32 utmp;
625                                 if (get_user(utmp,
626                                              (__u32 __force __user *) data))
627                                         return -EFAULT;
628                                 ret = poke_user_compat(child, addr, utmp);
629                         }
630                         if (ret)
631                                 return ret;
632                         addr += sizeof(unsigned int);
633                         data += sizeof(unsigned int);
634                         copied += sizeof(unsigned int);
635                 }
636                 return 0;
637         }
638         return compat_ptrace_request(child, request, addr, data);
639 }
640 #endif
641
642 asmlinkage void
643 syscall_trace(struct pt_regs *regs, int entryexit)
644 {
645         if (unlikely(current->audit_context) && entryexit)
646                 audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);
647
648         if (!test_thread_flag(TIF_SYSCALL_TRACE))
649                 goto out;
650         if (!(current->ptrace & PT_PTRACED))
651                 goto out;
652         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
653                                  ? 0x80 : 0));
654
655         /*
656          * If the debuffer has set an invalid system call number,
657          * we prepare to skip the system call restart handling.
658          */
659         if (!entryexit && regs->gprs[2] >= NR_syscalls)
660                 regs->trap = -1;
661
662         /*
663          * this isn't the same as continuing with a signal, but it will do
664          * for normal use.  strace only continues with a signal if the
665          * stopping signal is not SIGTRAP.  -brl
666          */
667         if (current->exit_code) {
668                 send_sig(current->exit_code, current, 1);
669                 current->exit_code = 0;
670         }
671  out:
672         if (unlikely(current->audit_context) && !entryexit)
673                 audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X,
674                                     regs->gprs[2], regs->orig_gpr2, regs->gprs[3],
675                                     regs->gprs[4], regs->gprs[5]);
676 }
677
678 /*
679  * user_regset definitions.
680  */
681
682 static int s390_regs_get(struct task_struct *target,
683                          const struct user_regset *regset,
684                          unsigned int pos, unsigned int count,
685                          void *kbuf, void __user *ubuf)
686 {
687         if (target == current)
688                 save_access_regs(target->thread.acrs);
689
690         if (kbuf) {
691                 unsigned long *k = kbuf;
692                 while (count > 0) {
693                         *k++ = __peek_user(target, pos);
694                         count -= sizeof(*k);
695                         pos += sizeof(*k);
696                 }
697         } else {
698                 unsigned long __user *u = ubuf;
699                 while (count > 0) {
700                         if (__put_user(__peek_user(target, pos), u++))
701                                 return -EFAULT;
702                         count -= sizeof(*u);
703                         pos += sizeof(*u);
704                 }
705         }
706         return 0;
707 }
708
709 static int s390_regs_set(struct task_struct *target,
710                          const struct user_regset *regset,
711                          unsigned int pos, unsigned int count,
712                          const void *kbuf, const void __user *ubuf)
713 {
714         int rc = 0;
715
716         if (target == current)
717                 save_access_regs(target->thread.acrs);
718
719         if (kbuf) {
720                 const unsigned long *k = kbuf;
721                 while (count > 0 && !rc) {
722                         rc = __poke_user(target, pos, *k++);
723                         count -= sizeof(*k);
724                         pos += sizeof(*k);
725                 }
726         } else {
727                 const unsigned long  __user *u = ubuf;
728                 while (count > 0 && !rc) {
729                         unsigned long word;
730                         rc = __get_user(word, u++);
731                         if (rc)
732                                 break;
733                         rc = __poke_user(target, pos, word);
734                         count -= sizeof(*u);
735                         pos += sizeof(*u);
736                 }
737         }
738
739         if (rc == 0 && target == current)
740                 restore_access_regs(target->thread.acrs);
741
742         return rc;
743 }
744
745 static int s390_fpregs_get(struct task_struct *target,
746                            const struct user_regset *regset, unsigned int pos,
747                            unsigned int count, void *kbuf, void __user *ubuf)
748 {
749         if (target == current)
750                 save_fp_regs(&target->thread.fp_regs);
751
752         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
753                                    &target->thread.fp_regs, 0, -1);
754 }
755
756 static int s390_fpregs_set(struct task_struct *target,
757                            const struct user_regset *regset, unsigned int pos,
758                            unsigned int count, const void *kbuf,
759                            const void __user *ubuf)
760 {
761         int rc = 0;
762
763         if (target == current)
764                 save_fp_regs(&target->thread.fp_regs);
765
766         /* If setting FPC, must validate it first. */
767         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
768                 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
769                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
770                                         0, offsetof(s390_fp_regs, fprs));
771                 if (rc)
772                         return rc;
773                 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
774                         return -EINVAL;
775                 target->thread.fp_regs.fpc = fpc[0];
776         }
777
778         if (rc == 0 && count > 0)
779                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
780                                         target->thread.fp_regs.fprs,
781                                         offsetof(s390_fp_regs, fprs), -1);
782
783         if (rc == 0 && target == current)
784                 restore_fp_regs(&target->thread.fp_regs);
785
786         return rc;
787 }
788
789 static const struct user_regset s390_regsets[] = {
790         [REGSET_GENERAL] = {
791                 .core_note_type = NT_PRSTATUS,
792                 .n = sizeof(s390_regs) / sizeof(long),
793                 .size = sizeof(long),
794                 .align = sizeof(long),
795                 .get = s390_regs_get,
796                 .set = s390_regs_set,
797         },
798         [REGSET_FP] = {
799                 .core_note_type = NT_PRFPREG,
800                 .n = sizeof(s390_fp_regs) / sizeof(long),
801                 .size = sizeof(long),
802                 .align = sizeof(long),
803                 .get = s390_fpregs_get,
804                 .set = s390_fpregs_set,
805         },
806 };
807
808 static const struct user_regset_view user_s390_view = {
809         .name = UTS_MACHINE,
810         .e_machine = EM_S390,
811         .regsets = s390_regsets,
812         .n = ARRAY_SIZE(s390_regsets)
813 };
814
815 #ifdef CONFIG_COMPAT
816 static int s390_compat_regs_get(struct task_struct *target,
817                                 const struct user_regset *regset,
818                                 unsigned int pos, unsigned int count,
819                                 void *kbuf, void __user *ubuf)
820 {
821         if (target == current)
822                 save_access_regs(target->thread.acrs);
823
824         if (kbuf) {
825                 compat_ulong_t *k = kbuf;
826                 while (count > 0) {
827                         *k++ = __peek_user_compat(target, pos);
828                         count -= sizeof(*k);
829                         pos += sizeof(*k);
830                 }
831         } else {
832                 compat_ulong_t __user *u = ubuf;
833                 while (count > 0) {
834                         if (__put_user(__peek_user_compat(target, pos), u++))
835                                 return -EFAULT;
836                         count -= sizeof(*u);
837                         pos += sizeof(*u);
838                 }
839         }
840         return 0;
841 }
842
843 static int s390_compat_regs_set(struct task_struct *target,
844                                 const struct user_regset *regset,
845                                 unsigned int pos, unsigned int count,
846                                 const void *kbuf, const void __user *ubuf)
847 {
848         int rc = 0;
849
850         if (target == current)
851                 save_access_regs(target->thread.acrs);
852
853         if (kbuf) {
854                 const compat_ulong_t *k = kbuf;
855                 while (count > 0 && !rc) {
856                         rc = __poke_user_compat(target, pos, *k++);
857                         count -= sizeof(*k);
858                         pos += sizeof(*k);
859                 }
860         } else {
861                 const compat_ulong_t  __user *u = ubuf;
862                 while (count > 0 && !rc) {
863                         compat_ulong_t word;
864                         rc = __get_user(word, u++);
865                         if (rc)
866                                 break;
867                         rc = __poke_user_compat(target, pos, word);
868                         count -= sizeof(*u);
869                         pos += sizeof(*u);
870                 }
871         }
872
873         if (rc == 0 && target == current)
874                 restore_access_regs(target->thread.acrs);
875
876         return rc;
877 }
878
879 static const struct user_regset s390_compat_regsets[] = {
880         [REGSET_GENERAL] = {
881                 .core_note_type = NT_PRSTATUS,
882                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
883                 .size = sizeof(compat_long_t),
884                 .align = sizeof(compat_long_t),
885                 .get = s390_compat_regs_get,
886                 .set = s390_compat_regs_set,
887         },
888         [REGSET_FP] = {
889                 .core_note_type = NT_PRFPREG,
890                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
891                 .size = sizeof(compat_long_t),
892                 .align = sizeof(compat_long_t),
893                 .get = s390_fpregs_get,
894                 .set = s390_fpregs_set,
895         },
896 };
897
898 static const struct user_regset_view user_s390_compat_view = {
899         .name = "s390",
900         .e_machine = EM_S390,
901         .regsets = s390_compat_regsets,
902         .n = ARRAY_SIZE(s390_compat_regsets)
903 };
904 #endif
905
906 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
907 {
908 #ifdef CONFIG_COMPAT
909         if (test_tsk_thread_flag(task, TIF_31BIT))
910                 return &user_s390_compat_view;
911 #endif
912         return &user_s390_view;
913 }