Merge branch 'linus' into x86/xen
[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 #include <linux/tracehook.h>
39
40 #include <asm/segment.h>
41 #include <asm/page.h>
42 #include <asm/pgtable.h>
43 #include <asm/pgalloc.h>
44 #include <asm/system.h>
45 #include <asm/uaccess.h>
46 #include <asm/unistd.h>
47 #include "entry.h"
48
49 #ifdef CONFIG_COMPAT
50 #include "compat_ptrace.h"
51 #endif
52
53 enum s390_regset {
54         REGSET_GENERAL,
55         REGSET_FP,
56 };
57
58 static void
59 FixPerRegisters(struct task_struct *task)
60 {
61         struct pt_regs *regs;
62         per_struct *per_info;
63
64         regs = task_pt_regs(task);
65         per_info = (per_struct *) &task->thread.per_info;
66         per_info->control_regs.bits.em_instruction_fetch =
67                 per_info->single_step | per_info->instruction_fetch;
68         
69         if (per_info->single_step) {
70                 per_info->control_regs.bits.starting_addr = 0;
71 #ifdef CONFIG_COMPAT
72                 if (test_thread_flag(TIF_31BIT))
73                         per_info->control_regs.bits.ending_addr = 0x7fffffffUL;
74                 else
75 #endif
76                         per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN;
77         } else {
78                 per_info->control_regs.bits.starting_addr =
79                         per_info->starting_addr;
80                 per_info->control_regs.bits.ending_addr =
81                         per_info->ending_addr;
82         }
83         /*
84          * if any of the control reg tracing bits are on 
85          * we switch on per in the psw
86          */
87         if (per_info->control_regs.words.cr[0] & PER_EM_MASK)
88                 regs->psw.mask |= PSW_MASK_PER;
89         else
90                 regs->psw.mask &= ~PSW_MASK_PER;
91
92         if (per_info->control_regs.bits.em_storage_alteration)
93                 per_info->control_regs.bits.storage_alt_space_ctl = 1;
94         else
95                 per_info->control_regs.bits.storage_alt_space_ctl = 0;
96 }
97
98 void user_enable_single_step(struct task_struct *task)
99 {
100         task->thread.per_info.single_step = 1;
101         FixPerRegisters(task);
102 }
103
104 void user_disable_single_step(struct task_struct *task)
105 {
106         task->thread.per_info.single_step = 0;
107         FixPerRegisters(task);
108 }
109
110 /*
111  * Called by kernel/ptrace.c when detaching..
112  *
113  * Make sure single step bits etc are not set.
114  */
115 void
116 ptrace_disable(struct task_struct *child)
117 {
118         /* make sure the single step bit is not set. */
119         user_disable_single_step(child);
120 }
121
122 #ifndef CONFIG_64BIT
123 # define __ADDR_MASK 3
124 #else
125 # define __ADDR_MASK 7
126 #endif
127
128 /*
129  * Read the word at offset addr from the user area of a process. The
130  * trouble here is that the information is littered over different
131  * locations. The process registers are found on the kernel stack,
132  * the floating point stuff and the trace settings are stored in
133  * the task structure. In addition the different structures in
134  * struct user contain pad bytes that should be read as zeroes.
135  * Lovely...
136  */
137 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
138 {
139         struct user *dummy = NULL;
140         addr_t offset, tmp;
141
142         if (addr < (addr_t) &dummy->regs.acrs) {
143                 /*
144                  * psw and gprs are stored on the stack
145                  */
146                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
147                 if (addr == (addr_t) &dummy->regs.psw.mask)
148                         /* Remove per bit from user psw. */
149                         tmp &= ~PSW_MASK_PER;
150
151         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
152                 /*
153                  * access registers are stored in the thread structure
154                  */
155                 offset = addr - (addr_t) &dummy->regs.acrs;
156 #ifdef CONFIG_64BIT
157                 /*
158                  * Very special case: old & broken 64 bit gdb reading
159                  * from acrs[15]. Result is a 64 bit value. Read the
160                  * 32 bit acrs[15] value and shift it by 32. Sick...
161                  */
162                 if (addr == (addr_t) &dummy->regs.acrs[15])
163                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
164                 else
165 #endif
166                 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
167
168         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
169                 /*
170                  * orig_gpr2 is stored on the kernel stack
171                  */
172                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
173
174         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
175                 /*
176                  * prevent reads of padding hole between
177                  * orig_gpr2 and fp_regs on s390.
178                  */
179                 tmp = 0;
180
181         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
182                 /* 
183                  * floating point regs. are stored in the thread structure
184                  */
185                 offset = addr - (addr_t) &dummy->regs.fp_regs;
186                 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
187                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
188                         tmp &= (unsigned long) FPC_VALID_MASK
189                                 << (BITS_PER_LONG - 32);
190
191         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
192                 /*
193                  * per_info is found in the thread structure
194                  */
195                 offset = addr - (addr_t) &dummy->regs.per_info;
196                 tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset);
197
198         } else
199                 tmp = 0;
200
201         return tmp;
202 }
203
204 static int
205 peek_user(struct task_struct *child, addr_t addr, addr_t data)
206 {
207         struct user *dummy = NULL;
208         addr_t tmp, mask;
209
210         /*
211          * Stupid gdb peeks/pokes the access registers in 64 bit with
212          * an alignment of 4. Programmers from hell...
213          */
214         mask = __ADDR_MASK;
215 #ifdef CONFIG_64BIT
216         if (addr >= (addr_t) &dummy->regs.acrs &&
217             addr < (addr_t) &dummy->regs.orig_gpr2)
218                 mask = 3;
219 #endif
220         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
221                 return -EIO;
222
223         tmp = __peek_user(child, addr);
224         return put_user(tmp, (addr_t __user *) data);
225 }
226
227 /*
228  * Write a word to the user area of a process at location addr. This
229  * operation does have an additional problem compared to peek_user.
230  * Stores to the program status word and on the floating point
231  * control register needs to get checked for validity.
232  */
233 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
234 {
235         struct user *dummy = NULL;
236         addr_t offset;
237
238         if (addr < (addr_t) &dummy->regs.acrs) {
239                 /*
240                  * psw and gprs are stored on the stack
241                  */
242                 if (addr == (addr_t) &dummy->regs.psw.mask &&
243 #ifdef CONFIG_COMPAT
244                     data != PSW_MASK_MERGE(psw_user32_bits, data) &&
245 #endif
246                     data != PSW_MASK_MERGE(psw_user_bits, data))
247                         /* Invalid psw mask. */
248                         return -EINVAL;
249 #ifndef CONFIG_64BIT
250                 if (addr == (addr_t) &dummy->regs.psw.addr)
251                         /* I'd like to reject addresses without the
252                            high order bit but older gdb's rely on it */
253                         data |= PSW_ADDR_AMODE;
254 #endif
255                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
256
257         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
258                 /*
259                  * access registers are stored in the thread structure
260                  */
261                 offset = addr - (addr_t) &dummy->regs.acrs;
262 #ifdef CONFIG_64BIT
263                 /*
264                  * Very special case: old & broken 64 bit gdb writing
265                  * to acrs[15] with a 64 bit value. Ignore the lower
266                  * half of the value and write the upper 32 bit to
267                  * acrs[15]. Sick...
268                  */
269                 if (addr == (addr_t) &dummy->regs.acrs[15])
270                         child->thread.acrs[15] = (unsigned int) (data >> 32);
271                 else
272 #endif
273                 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
274
275         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
276                 /*
277                  * orig_gpr2 is stored on the kernel stack
278                  */
279                 task_pt_regs(child)->orig_gpr2 = data;
280
281         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
282                 /*
283                  * prevent writes of padding hole between
284                  * orig_gpr2 and fp_regs on s390.
285                  */
286                 return 0;
287
288         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
289                 /*
290                  * floating point regs. are stored in the thread structure
291                  */
292                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
293                     (data & ~((unsigned long) FPC_VALID_MASK
294                               << (BITS_PER_LONG - 32))) != 0)
295                         return -EINVAL;
296                 offset = addr - (addr_t) &dummy->regs.fp_regs;
297                 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
298
299         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
300                 /*
301                  * per_info is found in the thread structure 
302                  */
303                 offset = addr - (addr_t) &dummy->regs.per_info;
304                 *(addr_t *)((addr_t) &child->thread.per_info + offset) = data;
305
306         }
307
308         FixPerRegisters(child);
309         return 0;
310 }
311
312 static int
313 poke_user(struct task_struct *child, addr_t addr, addr_t data)
314 {
315         struct user *dummy = NULL;
316         addr_t mask;
317
318         /*
319          * Stupid gdb peeks/pokes the access registers in 64 bit with
320          * an alignment of 4. Programmers from hell indeed...
321          */
322         mask = __ADDR_MASK;
323 #ifdef CONFIG_64BIT
324         if (addr >= (addr_t) &dummy->regs.acrs &&
325             addr < (addr_t) &dummy->regs.orig_gpr2)
326                 mask = 3;
327 #endif
328         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
329                 return -EIO;
330
331         return __poke_user(child, addr, data);
332 }
333
334 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
335 {
336         ptrace_area parea; 
337         int copied, ret;
338
339         switch (request) {
340         case PTRACE_PEEKTEXT:
341         case PTRACE_PEEKDATA:
342                 /* Remove high order bit from address (only for 31 bit). */
343                 addr &= PSW_ADDR_INSN;
344                 /* read word at location addr. */
345                 return generic_ptrace_peekdata(child, addr, data);
346
347         case PTRACE_PEEKUSR:
348                 /* read the word at location addr in the USER area. */
349                 return peek_user(child, addr, data);
350
351         case PTRACE_POKETEXT:
352         case PTRACE_POKEDATA:
353                 /* Remove high order bit from address (only for 31 bit). */
354                 addr &= PSW_ADDR_INSN;
355                 /* write the word at location addr. */
356                 return generic_ptrace_pokedata(child, addr, data);
357
358         case PTRACE_POKEUSR:
359                 /* write the word at location addr in the USER area */
360                 return poke_user(child, addr, data);
361
362         case PTRACE_PEEKUSR_AREA:
363         case PTRACE_POKEUSR_AREA:
364                 if (copy_from_user(&parea, (void __force __user *) addr,
365                                                         sizeof(parea)))
366                         return -EFAULT;
367                 addr = parea.kernel_addr;
368                 data = parea.process_addr;
369                 copied = 0;
370                 while (copied < parea.len) {
371                         if (request == PTRACE_PEEKUSR_AREA)
372                                 ret = peek_user(child, addr, data);
373                         else {
374                                 addr_t utmp;
375                                 if (get_user(utmp,
376                                              (addr_t __force __user *) data))
377                                         return -EFAULT;
378                                 ret = poke_user(child, addr, utmp);
379                         }
380                         if (ret)
381                                 return ret;
382                         addr += sizeof(unsigned long);
383                         data += sizeof(unsigned long);
384                         copied += sizeof(unsigned long);
385                 }
386                 return 0;
387         }
388         return ptrace_request(child, request, addr, data);
389 }
390
391 #ifdef CONFIG_COMPAT
392 /*
393  * Now the fun part starts... a 31 bit program running in the
394  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
395  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
396  * to handle, the difference to the 64 bit versions of the requests
397  * is that the access is done in multiples of 4 byte instead of
398  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
399  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
400  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
401  * is a 31 bit program too, the content of struct user can be
402  * emulated. A 31 bit program peeking into the struct user of
403  * a 64 bit program is a no-no.
404  */
405
406 /*
407  * Same as peek_user but for a 31 bit program.
408  */
409 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
410 {
411         struct user32 *dummy32 = NULL;
412         per_struct32 *dummy_per32 = NULL;
413         addr_t offset;
414         __u32 tmp;
415
416         if (addr < (addr_t) &dummy32->regs.acrs) {
417                 /*
418                  * psw and gprs are stored on the stack
419                  */
420                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
421                         /* Fake a 31 bit psw mask. */
422                         tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
423                         tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
424                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
425                         /* Fake a 31 bit psw address. */
426                         tmp = (__u32) task_pt_regs(child)->psw.addr |
427                                 PSW32_ADDR_AMODE31;
428                 } else {
429                         /* gpr 0-15 */
430                         tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
431                                          addr*2 + 4);
432                 }
433         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
434                 /*
435                  * access registers are stored in the thread structure
436                  */
437                 offset = addr - (addr_t) &dummy32->regs.acrs;
438                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
439
440         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
441                 /*
442                  * orig_gpr2 is stored on the kernel stack
443                  */
444                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
445
446         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
447                 /*
448                  * prevent reads of padding hole between
449                  * orig_gpr2 and fp_regs on s390.
450                  */
451                 tmp = 0;
452
453         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
454                 /*
455                  * floating point regs. are stored in the thread structure 
456                  */
457                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
458                 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
459
460         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
461                 /*
462                  * per_info is found in the thread structure
463                  */
464                 offset = addr - (addr_t) &dummy32->regs.per_info;
465                 /* This is magic. See per_struct and per_struct32. */
466                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
467                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
468                     (offset >= (addr_t) &dummy_per32->starting_addr &&
469                      offset <= (addr_t) &dummy_per32->ending_addr) ||
470                     offset == (addr_t) &dummy_per32->lowcore.words.address)
471                         offset = offset*2 + 4;
472                 else
473                         offset = offset*2;
474                 tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset);
475
476         } else
477                 tmp = 0;
478
479         return tmp;
480 }
481
482 static int peek_user_compat(struct task_struct *child,
483                             addr_t addr, addr_t data)
484 {
485         __u32 tmp;
486
487         if (!test_thread_flag(TIF_31BIT) ||
488             (addr & 3) || addr > sizeof(struct user) - 3)
489                 return -EIO;
490
491         tmp = __peek_user_compat(child, addr);
492         return put_user(tmp, (__u32 __user *) data);
493 }
494
495 /*
496  * Same as poke_user but for a 31 bit program.
497  */
498 static int __poke_user_compat(struct task_struct *child,
499                               addr_t addr, addr_t data)
500 {
501         struct user32 *dummy32 = NULL;
502         per_struct32 *dummy_per32 = NULL;
503         __u32 tmp = (__u32) data;
504         addr_t offset;
505
506         if (addr < (addr_t) &dummy32->regs.acrs) {
507                 /*
508                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
509                  */
510                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
511                         /* Build a 64 bit psw mask from 31 bit mask. */
512                         if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
513                                 /* Invalid psw mask. */
514                                 return -EINVAL;
515                         task_pt_regs(child)->psw.mask =
516                                 PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
517                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
518                         /* Build a 64 bit psw address from 31 bit address. */
519                         task_pt_regs(child)->psw.addr =
520                                 (__u64) tmp & PSW32_ADDR_INSN;
521                 } else {
522                         /* gpr 0-15 */
523                         *(__u32*)((addr_t) &task_pt_regs(child)->psw
524                                   + addr*2 + 4) = tmp;
525                 }
526         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
527                 /*
528                  * access registers are stored in the thread structure
529                  */
530                 offset = addr - (addr_t) &dummy32->regs.acrs;
531                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
532
533         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
534                 /*
535                  * orig_gpr2 is stored on the kernel stack
536                  */
537                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
538
539         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
540                 /*
541                  * prevent writess of padding hole between
542                  * orig_gpr2 and fp_regs on s390.
543                  */
544                 return 0;
545
546         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
547                 /*
548                  * floating point regs. are stored in the thread structure 
549                  */
550                 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
551                     (tmp & ~FPC_VALID_MASK) != 0)
552                         /* Invalid floating point control. */
553                         return -EINVAL;
554                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
555                 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
556
557         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
558                 /*
559                  * per_info is found in the thread structure.
560                  */
561                 offset = addr - (addr_t) &dummy32->regs.per_info;
562                 /*
563                  * This is magic. See per_struct and per_struct32.
564                  * By incident the offsets in per_struct are exactly
565                  * twice the offsets in per_struct32 for all fields.
566                  * The 8 byte fields need special handling though,
567                  * because the second half (bytes 4-7) is needed and
568                  * not the first half.
569                  */
570                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
571                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
572                     (offset >= (addr_t) &dummy_per32->starting_addr &&
573                      offset <= (addr_t) &dummy_per32->ending_addr) ||
574                     offset == (addr_t) &dummy_per32->lowcore.words.address)
575                         offset = offset*2 + 4;
576                 else
577                         offset = offset*2;
578                 *(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp;
579
580         }
581
582         FixPerRegisters(child);
583         return 0;
584 }
585
586 static int poke_user_compat(struct task_struct *child,
587                             addr_t addr, addr_t data)
588 {
589         if (!test_thread_flag(TIF_31BIT) ||
590             (addr & 3) || addr > sizeof(struct user32) - 3)
591                 return -EIO;
592
593         return __poke_user_compat(child, addr, data);
594 }
595
596 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
597                         compat_ulong_t caddr, compat_ulong_t cdata)
598 {
599         unsigned long addr = caddr;
600         unsigned long data = cdata;
601         ptrace_area_emu31 parea; 
602         int copied, ret;
603
604         switch (request) {
605         case PTRACE_PEEKUSR:
606                 /* read the word at location addr in the USER area. */
607                 return peek_user_compat(child, addr, data);
608
609         case PTRACE_POKEUSR:
610                 /* write the word at location addr in the USER area */
611                 return poke_user_compat(child, addr, data);
612
613         case PTRACE_PEEKUSR_AREA:
614         case PTRACE_POKEUSR_AREA:
615                 if (copy_from_user(&parea, (void __force __user *) addr,
616                                                         sizeof(parea)))
617                         return -EFAULT;
618                 addr = parea.kernel_addr;
619                 data = parea.process_addr;
620                 copied = 0;
621                 while (copied < parea.len) {
622                         if (request == PTRACE_PEEKUSR_AREA)
623                                 ret = peek_user_compat(child, addr, data);
624                         else {
625                                 __u32 utmp;
626                                 if (get_user(utmp,
627                                              (__u32 __force __user *) data))
628                                         return -EFAULT;
629                                 ret = poke_user_compat(child, addr, utmp);
630                         }
631                         if (ret)
632                                 return ret;
633                         addr += sizeof(unsigned int);
634                         data += sizeof(unsigned int);
635                         copied += sizeof(unsigned int);
636                 }
637                 return 0;
638         }
639         return compat_ptrace_request(child, request, addr, data);
640 }
641 #endif
642
643 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
644 {
645         long ret;
646
647         /*
648          * The sysc_tracesys code in entry.S stored the system
649          * call number to gprs[2].
650          */
651         ret = regs->gprs[2];
652         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
653             (tracehook_report_syscall_entry(regs) ||
654              regs->gprs[2] >= NR_syscalls)) {
655                 /*
656                  * Tracing decided this syscall should not happen or the
657                  * debugger stored an invalid system call number. Skip
658                  * the system call and the system call restart handling.
659                  */
660                 regs->trap = -1;
661                 ret = -1;
662         }
663
664         if (unlikely(current->audit_context))
665                 audit_syscall_entry(test_thread_flag(TIF_31BIT) ?
666                                         AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
667                                     regs->gprs[2], regs->orig_gpr2,
668                                     regs->gprs[3], regs->gprs[4],
669                                     regs->gprs[5]);
670         return ret;
671 }
672
673 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
674 {
675         if (unlikely(current->audit_context))
676                 audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
677                                    regs->gprs[2]);
678
679         if (test_thread_flag(TIF_SYSCALL_TRACE))
680                 tracehook_report_syscall_exit(regs, 0);
681 }
682
683 /*
684  * user_regset definitions.
685  */
686
687 static int s390_regs_get(struct task_struct *target,
688                          const struct user_regset *regset,
689                          unsigned int pos, unsigned int count,
690                          void *kbuf, void __user *ubuf)
691 {
692         if (target == current)
693                 save_access_regs(target->thread.acrs);
694
695         if (kbuf) {
696                 unsigned long *k = kbuf;
697                 while (count > 0) {
698                         *k++ = __peek_user(target, pos);
699                         count -= sizeof(*k);
700                         pos += sizeof(*k);
701                 }
702         } else {
703                 unsigned long __user *u = ubuf;
704                 while (count > 0) {
705                         if (__put_user(__peek_user(target, pos), u++))
706                                 return -EFAULT;
707                         count -= sizeof(*u);
708                         pos += sizeof(*u);
709                 }
710         }
711         return 0;
712 }
713
714 static int s390_regs_set(struct task_struct *target,
715                          const struct user_regset *regset,
716                          unsigned int pos, unsigned int count,
717                          const void *kbuf, const void __user *ubuf)
718 {
719         int rc = 0;
720
721         if (target == current)
722                 save_access_regs(target->thread.acrs);
723
724         if (kbuf) {
725                 const unsigned long *k = kbuf;
726                 while (count > 0 && !rc) {
727                         rc = __poke_user(target, pos, *k++);
728                         count -= sizeof(*k);
729                         pos += sizeof(*k);
730                 }
731         } else {
732                 const unsigned long  __user *u = ubuf;
733                 while (count > 0 && !rc) {
734                         unsigned long word;
735                         rc = __get_user(word, u++);
736                         if (rc)
737                                 break;
738                         rc = __poke_user(target, pos, word);
739                         count -= sizeof(*u);
740                         pos += sizeof(*u);
741                 }
742         }
743
744         if (rc == 0 && target == current)
745                 restore_access_regs(target->thread.acrs);
746
747         return rc;
748 }
749
750 static int s390_fpregs_get(struct task_struct *target,
751                            const struct user_regset *regset, unsigned int pos,
752                            unsigned int count, void *kbuf, void __user *ubuf)
753 {
754         if (target == current)
755                 save_fp_regs(&target->thread.fp_regs);
756
757         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
758                                    &target->thread.fp_regs, 0, -1);
759 }
760
761 static int s390_fpregs_set(struct task_struct *target,
762                            const struct user_regset *regset, unsigned int pos,
763                            unsigned int count, const void *kbuf,
764                            const void __user *ubuf)
765 {
766         int rc = 0;
767
768         if (target == current)
769                 save_fp_regs(&target->thread.fp_regs);
770
771         /* If setting FPC, must validate it first. */
772         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
773                 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
774                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
775                                         0, offsetof(s390_fp_regs, fprs));
776                 if (rc)
777                         return rc;
778                 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
779                         return -EINVAL;
780                 target->thread.fp_regs.fpc = fpc[0];
781         }
782
783         if (rc == 0 && count > 0)
784                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
785                                         target->thread.fp_regs.fprs,
786                                         offsetof(s390_fp_regs, fprs), -1);
787
788         if (rc == 0 && target == current)
789                 restore_fp_regs(&target->thread.fp_regs);
790
791         return rc;
792 }
793
794 static const struct user_regset s390_regsets[] = {
795         [REGSET_GENERAL] = {
796                 .core_note_type = NT_PRSTATUS,
797                 .n = sizeof(s390_regs) / sizeof(long),
798                 .size = sizeof(long),
799                 .align = sizeof(long),
800                 .get = s390_regs_get,
801                 .set = s390_regs_set,
802         },
803         [REGSET_FP] = {
804                 .core_note_type = NT_PRFPREG,
805                 .n = sizeof(s390_fp_regs) / sizeof(long),
806                 .size = sizeof(long),
807                 .align = sizeof(long),
808                 .get = s390_fpregs_get,
809                 .set = s390_fpregs_set,
810         },
811 };
812
813 static const struct user_regset_view user_s390_view = {
814         .name = UTS_MACHINE,
815         .e_machine = EM_S390,
816         .regsets = s390_regsets,
817         .n = ARRAY_SIZE(s390_regsets)
818 };
819
820 #ifdef CONFIG_COMPAT
821 static int s390_compat_regs_get(struct task_struct *target,
822                                 const struct user_regset *regset,
823                                 unsigned int pos, unsigned int count,
824                                 void *kbuf, void __user *ubuf)
825 {
826         if (target == current)
827                 save_access_regs(target->thread.acrs);
828
829         if (kbuf) {
830                 compat_ulong_t *k = kbuf;
831                 while (count > 0) {
832                         *k++ = __peek_user_compat(target, pos);
833                         count -= sizeof(*k);
834                         pos += sizeof(*k);
835                 }
836         } else {
837                 compat_ulong_t __user *u = ubuf;
838                 while (count > 0) {
839                         if (__put_user(__peek_user_compat(target, pos), u++))
840                                 return -EFAULT;
841                         count -= sizeof(*u);
842                         pos += sizeof(*u);
843                 }
844         }
845         return 0;
846 }
847
848 static int s390_compat_regs_set(struct task_struct *target,
849                                 const struct user_regset *regset,
850                                 unsigned int pos, unsigned int count,
851                                 const void *kbuf, const void __user *ubuf)
852 {
853         int rc = 0;
854
855         if (target == current)
856                 save_access_regs(target->thread.acrs);
857
858         if (kbuf) {
859                 const compat_ulong_t *k = kbuf;
860                 while (count > 0 && !rc) {
861                         rc = __poke_user_compat(target, pos, *k++);
862                         count -= sizeof(*k);
863                         pos += sizeof(*k);
864                 }
865         } else {
866                 const compat_ulong_t  __user *u = ubuf;
867                 while (count > 0 && !rc) {
868                         compat_ulong_t word;
869                         rc = __get_user(word, u++);
870                         if (rc)
871                                 break;
872                         rc = __poke_user_compat(target, pos, word);
873                         count -= sizeof(*u);
874                         pos += sizeof(*u);
875                 }
876         }
877
878         if (rc == 0 && target == current)
879                 restore_access_regs(target->thread.acrs);
880
881         return rc;
882 }
883
884 static const struct user_regset s390_compat_regsets[] = {
885         [REGSET_GENERAL] = {
886                 .core_note_type = NT_PRSTATUS,
887                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
888                 .size = sizeof(compat_long_t),
889                 .align = sizeof(compat_long_t),
890                 .get = s390_compat_regs_get,
891                 .set = s390_compat_regs_set,
892         },
893         [REGSET_FP] = {
894                 .core_note_type = NT_PRFPREG,
895                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
896                 .size = sizeof(compat_long_t),
897                 .align = sizeof(compat_long_t),
898                 .get = s390_fpregs_get,
899                 .set = s390_fpregs_set,
900         },
901 };
902
903 static const struct user_regset_view user_s390_compat_view = {
904         .name = "s390",
905         .e_machine = EM_S390,
906         .regsets = s390_compat_regsets,
907         .n = ARRAY_SIZE(s390_compat_regsets)
908 };
909 #endif
910
911 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
912 {
913 #ifdef CONFIG_COMPAT
914         if (test_tsk_thread_flag(task, TIF_31BIT))
915                 return &user_s390_compat_view;
916 #endif
917         return &user_s390_view;
918 }