GNU Linux-libre 5.10.217-gnu1
[releases.git] / arch / ia64 / kernel / ptrace.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Kernel support for the ptrace() and syscall tracing interfaces.
4  *
5  * Copyright (C) 1999-2005 Hewlett-Packard Co
6  *      David Mosberger-Tang <davidm@hpl.hp.com>
7  * Copyright (C) 2006 Intel Co
8  *  2006-08-12  - IA64 Native Utrace implementation support added by
9  *      Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
10  *
11  * Derived from the x86 and Alpha versions.
12  */
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/sched/task.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/mm.h>
18 #include <linux/errno.h>
19 #include <linux/ptrace.h>
20 #include <linux/user.h>
21 #include <linux/security.h>
22 #include <linux/audit.h>
23 #include <linux/signal.h>
24 #include <linux/regset.h>
25 #include <linux/elf.h>
26 #include <linux/tracehook.h>
27
28 #include <asm/processor.h>
29 #include <asm/ptrace_offsets.h>
30 #include <asm/rse.h>
31 #include <linux/uaccess.h>
32 #include <asm/unwind.h>
33
34 #include "entry.h"
35
36 /*
37  * Bits in the PSR that we allow ptrace() to change:
38  *      be, up, ac, mfl, mfh (the user mask; five bits total)
39  *      db (debug breakpoint fault; one bit)
40  *      id (instruction debug fault disable; one bit)
41  *      dd (data debug fault disable; one bit)
42  *      ri (restart instruction; two bits)
43  *      is (instruction set; one bit)
44  */
45 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS      \
46                    | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
47
48 #define MASK(nbits)     ((1UL << (nbits)) - 1)  /* mask with NBITS bits set */
49 #define PFM_MASK        MASK(38)
50
51 #define PTRACE_DEBUG    0
52
53 #if PTRACE_DEBUG
54 # define dprintk(format...)     printk(format)
55 # define inline
56 #else
57 # define dprintk(format...)
58 #endif
59
60 /* Return TRUE if PT was created due to kernel-entry via a system-call.  */
61
62 static inline int
63 in_syscall (struct pt_regs *pt)
64 {
65         return (long) pt->cr_ifs >= 0;
66 }
67
68 /*
69  * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
70  * bitset where bit i is set iff the NaT bit of register i is set.
71  */
72 unsigned long
73 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
74 {
75 #       define GET_BITS(first, last, unat)                              \
76         ({                                                              \
77                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
78                 unsigned long nbits = (last - first + 1);               \
79                 unsigned long mask = MASK(nbits) << first;              \
80                 unsigned long dist;                                     \
81                 if (bit < first)                                        \
82                         dist = 64 + bit - first;                        \
83                 else                                                    \
84                         dist = bit - first;                             \
85                 ia64_rotr(unat, dist) & mask;                           \
86         })
87         unsigned long val;
88
89         /*
90          * Registers that are stored consecutively in struct pt_regs
91          * can be handled in parallel.  If the register order in
92          * struct_pt_regs changes, this code MUST be updated.
93          */
94         val  = GET_BITS( 1,  1, scratch_unat);
95         val |= GET_BITS( 2,  3, scratch_unat);
96         val |= GET_BITS(12, 13, scratch_unat);
97         val |= GET_BITS(14, 14, scratch_unat);
98         val |= GET_BITS(15, 15, scratch_unat);
99         val |= GET_BITS( 8, 11, scratch_unat);
100         val |= GET_BITS(16, 31, scratch_unat);
101         return val;
102
103 #       undef GET_BITS
104 }
105
106 /*
107  * Set the NaT bits for the scratch registers according to NAT and
108  * return the resulting unat (assuming the scratch registers are
109  * stored in PT).
110  */
111 unsigned long
112 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
113 {
114 #       define PUT_BITS(first, last, nat)                               \
115         ({                                                              \
116                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
117                 unsigned long nbits = (last - first + 1);               \
118                 unsigned long mask = MASK(nbits) << first;              \
119                 long dist;                                              \
120                 if (bit < first)                                        \
121                         dist = 64 + bit - first;                        \
122                 else                                                    \
123                         dist = bit - first;                             \
124                 ia64_rotl(nat & mask, dist);                            \
125         })
126         unsigned long scratch_unat;
127
128         /*
129          * Registers that are stored consecutively in struct pt_regs
130          * can be handled in parallel.  If the register order in
131          * struct_pt_regs changes, this code MUST be updated.
132          */
133         scratch_unat  = PUT_BITS( 1,  1, nat);
134         scratch_unat |= PUT_BITS( 2,  3, nat);
135         scratch_unat |= PUT_BITS(12, 13, nat);
136         scratch_unat |= PUT_BITS(14, 14, nat);
137         scratch_unat |= PUT_BITS(15, 15, nat);
138         scratch_unat |= PUT_BITS( 8, 11, nat);
139         scratch_unat |= PUT_BITS(16, 31, nat);
140
141         return scratch_unat;
142
143 #       undef PUT_BITS
144 }
145
146 #define IA64_MLX_TEMPLATE       0x2
147 #define IA64_MOVL_OPCODE        6
148
149 void
150 ia64_increment_ip (struct pt_regs *regs)
151 {
152         unsigned long w0, ri = ia64_psr(regs)->ri + 1;
153
154         if (ri > 2) {
155                 ri = 0;
156                 regs->cr_iip += 16;
157         } else if (ri == 2) {
158                 get_user(w0, (char __user *) regs->cr_iip + 0);
159                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
160                         /*
161                          * rfi'ing to slot 2 of an MLX bundle causes
162                          * an illegal operation fault.  We don't want
163                          * that to happen...
164                          */
165                         ri = 0;
166                         regs->cr_iip += 16;
167                 }
168         }
169         ia64_psr(regs)->ri = ri;
170 }
171
172 void
173 ia64_decrement_ip (struct pt_regs *regs)
174 {
175         unsigned long w0, ri = ia64_psr(regs)->ri - 1;
176
177         if (ia64_psr(regs)->ri == 0) {
178                 regs->cr_iip -= 16;
179                 ri = 2;
180                 get_user(w0, (char __user *) regs->cr_iip + 0);
181                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
182                         /*
183                          * rfi'ing to slot 2 of an MLX bundle causes
184                          * an illegal operation fault.  We don't want
185                          * that to happen...
186                          */
187                         ri = 1;
188                 }
189         }
190         ia64_psr(regs)->ri = ri;
191 }
192
193 /*
194  * This routine is used to read an rnat bits that are stored on the
195  * kernel backing store.  Since, in general, the alignment of the user
196  * and kernel are different, this is not completely trivial.  In
197  * essence, we need to construct the user RNAT based on up to two
198  * kernel RNAT values and/or the RNAT value saved in the child's
199  * pt_regs.
200  *
201  * user rbs
202  *
203  * +--------+ <-- lowest address
204  * | slot62 |
205  * +--------+
206  * |  rnat  | 0x....1f8
207  * +--------+
208  * | slot00 | \
209  * +--------+ |
210  * | slot01 | > child_regs->ar_rnat
211  * +--------+ |
212  * | slot02 | /                         kernel rbs
213  * +--------+                           +--------+
214  *          <- child_regs->ar_bspstore  | slot61 | <-- krbs
215  * +- - - - +                           +--------+
216  *                                      | slot62 |
217  * +- - - - +                           +--------+
218  *                                      |  rnat  |
219  * +- - - - +                           +--------+
220  *   vrnat                              | slot00 |
221  * +- - - - +                           +--------+
222  *                                      =        =
223  *                                      +--------+
224  *                                      | slot00 | \
225  *                                      +--------+ |
226  *                                      | slot01 | > child_stack->ar_rnat
227  *                                      +--------+ |
228  *                                      | slot02 | /
229  *                                      +--------+
230  *                                                <--- child_stack->ar_bspstore
231  *
232  * The way to think of this code is as follows: bit 0 in the user rnat
233  * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
234  * value.  The kernel rnat value holding this bit is stored in
235  * variable rnat0.  rnat1 is loaded with the kernel rnat value that
236  * form the upper bits of the user rnat value.
237  *
238  * Boundary cases:
239  *
240  * o when reading the rnat "below" the first rnat slot on the kernel
241  *   backing store, rnat0/rnat1 are set to 0 and the low order bits are
242  *   merged in from pt->ar_rnat.
243  *
244  * o when reading the rnat "above" the last rnat slot on the kernel
245  *   backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
246  */
247 static unsigned long
248 get_rnat (struct task_struct *task, struct switch_stack *sw,
249           unsigned long *krbs, unsigned long *urnat_addr,
250           unsigned long *urbs_end)
251 {
252         unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
253         unsigned long umask = 0, mask, m;
254         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
255         long num_regs, nbits;
256         struct pt_regs *pt;
257
258         pt = task_pt_regs(task);
259         kbsp = (unsigned long *) sw->ar_bspstore;
260         ubspstore = (unsigned long *) pt->ar_bspstore;
261
262         if (urbs_end < urnat_addr)
263                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
264         else
265                 nbits = 63;
266         mask = MASK(nbits);
267         /*
268          * First, figure out which bit number slot 0 in user-land maps
269          * to in the kernel rnat.  Do this by figuring out how many
270          * register slots we're beyond the user's backingstore and
271          * then computing the equivalent address in kernel space.
272          */
273         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
274         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
275         shift = ia64_rse_slot_num(slot0_kaddr);
276         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
277         rnat0_kaddr = rnat1_kaddr - 64;
278
279         if (ubspstore + 63 > urnat_addr) {
280                 /* some bits need to be merged in from pt->ar_rnat */
281                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
282                 urnat = (pt->ar_rnat & umask);
283                 mask &= ~umask;
284                 if (!mask)
285                         return urnat;
286         }
287
288         m = mask << shift;
289         if (rnat0_kaddr >= kbsp)
290                 rnat0 = sw->ar_rnat;
291         else if (rnat0_kaddr > krbs)
292                 rnat0 = *rnat0_kaddr;
293         urnat |= (rnat0 & m) >> shift;
294
295         m = mask >> (63 - shift);
296         if (rnat1_kaddr >= kbsp)
297                 rnat1 = sw->ar_rnat;
298         else if (rnat1_kaddr > krbs)
299                 rnat1 = *rnat1_kaddr;
300         urnat |= (rnat1 & m) << (63 - shift);
301         return urnat;
302 }
303
304 /*
305  * The reverse of get_rnat.
306  */
307 static void
308 put_rnat (struct task_struct *task, struct switch_stack *sw,
309           unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
310           unsigned long *urbs_end)
311 {
312         unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
313         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
314         long num_regs, nbits;
315         struct pt_regs *pt;
316         unsigned long cfm, *urbs_kargs;
317
318         pt = task_pt_regs(task);
319         kbsp = (unsigned long *) sw->ar_bspstore;
320         ubspstore = (unsigned long *) pt->ar_bspstore;
321
322         urbs_kargs = urbs_end;
323         if (in_syscall(pt)) {
324                 /*
325                  * If entered via syscall, don't allow user to set rnat bits
326                  * for syscall args.
327                  */
328                 cfm = pt->cr_ifs;
329                 urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
330         }
331
332         if (urbs_kargs >= urnat_addr)
333                 nbits = 63;
334         else {
335                 if ((urnat_addr - 63) >= urbs_kargs)
336                         return;
337                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
338         }
339         mask = MASK(nbits);
340
341         /*
342          * First, figure out which bit number slot 0 in user-land maps
343          * to in the kernel rnat.  Do this by figuring out how many
344          * register slots we're beyond the user's backingstore and
345          * then computing the equivalent address in kernel space.
346          */
347         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
348         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
349         shift = ia64_rse_slot_num(slot0_kaddr);
350         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
351         rnat0_kaddr = rnat1_kaddr - 64;
352
353         if (ubspstore + 63 > urnat_addr) {
354                 /* some bits need to be place in pt->ar_rnat: */
355                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
356                 pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
357                 mask &= ~umask;
358                 if (!mask)
359                         return;
360         }
361         /*
362          * Note: Section 11.1 of the EAS guarantees that bit 63 of an
363          * rnat slot is ignored. so we don't have to clear it here.
364          */
365         rnat0 = (urnat << shift);
366         m = mask << shift;
367         if (rnat0_kaddr >= kbsp)
368                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
369         else if (rnat0_kaddr > krbs)
370                 *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
371
372         rnat1 = (urnat >> (63 - shift));
373         m = mask >> (63 - shift);
374         if (rnat1_kaddr >= kbsp)
375                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
376         else if (rnat1_kaddr > krbs)
377                 *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
378 }
379
380 static inline int
381 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
382                unsigned long urbs_end)
383 {
384         unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
385                                                       urbs_end);
386         return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
387 }
388
389 /*
390  * Read a word from the user-level backing store of task CHILD.  ADDR
391  * is the user-level address to read the word from, VAL a pointer to
392  * the return value, and USER_BSP gives the end of the user-level
393  * backing store (i.e., it's the address that would be in ar.bsp after
394  * the user executed a "cover" instruction).
395  *
396  * This routine takes care of accessing the kernel register backing
397  * store for those registers that got spilled there.  It also takes
398  * care of calculating the appropriate RNaT collection words.
399  */
400 long
401 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
402            unsigned long user_rbs_end, unsigned long addr, long *val)
403 {
404         unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
405         struct pt_regs *child_regs;
406         size_t copied;
407         long ret;
408
409         urbs_end = (long *) user_rbs_end;
410         laddr = (unsigned long *) addr;
411         child_regs = task_pt_regs(child);
412         bspstore = (unsigned long *) child_regs->ar_bspstore;
413         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
414         if (on_kernel_rbs(addr, (unsigned long) bspstore,
415                           (unsigned long) urbs_end))
416         {
417                 /*
418                  * Attempt to read the RBS in an area that's actually
419                  * on the kernel RBS => read the corresponding bits in
420                  * the kernel RBS.
421                  */
422                 rnat_addr = ia64_rse_rnat_addr(laddr);
423                 ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
424
425                 if (laddr == rnat_addr) {
426                         /* return NaT collection word itself */
427                         *val = ret;
428                         return 0;
429                 }
430
431                 if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
432                         /*
433                          * It is implementation dependent whether the
434                          * data portion of a NaT value gets saved on a
435                          * st8.spill or RSE spill (e.g., see EAS 2.6,
436                          * 4.4.4.6 Register Spill and Fill).  To get
437                          * consistent behavior across all possible
438                          * IA-64 implementations, we return zero in
439                          * this case.
440                          */
441                         *val = 0;
442                         return 0;
443                 }
444
445                 if (laddr < urbs_end) {
446                         /*
447                          * The desired word is on the kernel RBS and
448                          * is not a NaT.
449                          */
450                         regnum = ia64_rse_num_regs(bspstore, laddr);
451                         *val = *ia64_rse_skip_regs(krbs, regnum);
452                         return 0;
453                 }
454         }
455         copied = access_process_vm(child, addr, &ret, sizeof(ret), FOLL_FORCE);
456         if (copied != sizeof(ret))
457                 return -EIO;
458         *val = ret;
459         return 0;
460 }
461
462 long
463 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
464            unsigned long user_rbs_end, unsigned long addr, long val)
465 {
466         unsigned long *bspstore, *krbs, regnum, *laddr;
467         unsigned long *urbs_end = (long *) user_rbs_end;
468         struct pt_regs *child_regs;
469
470         laddr = (unsigned long *) addr;
471         child_regs = task_pt_regs(child);
472         bspstore = (unsigned long *) child_regs->ar_bspstore;
473         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
474         if (on_kernel_rbs(addr, (unsigned long) bspstore,
475                           (unsigned long) urbs_end))
476         {
477                 /*
478                  * Attempt to write the RBS in an area that's actually
479                  * on the kernel RBS => write the corresponding bits
480                  * in the kernel RBS.
481                  */
482                 if (ia64_rse_is_rnat_slot(laddr))
483                         put_rnat(child, child_stack, krbs, laddr, val,
484                                  urbs_end);
485                 else {
486                         if (laddr < urbs_end) {
487                                 regnum = ia64_rse_num_regs(bspstore, laddr);
488                                 *ia64_rse_skip_regs(krbs, regnum) = val;
489                         }
490                 }
491         } else if (access_process_vm(child, addr, &val, sizeof(val),
492                                 FOLL_FORCE | FOLL_WRITE)
493                    != sizeof(val))
494                 return -EIO;
495         return 0;
496 }
497
498 /*
499  * Calculate the address of the end of the user-level register backing
500  * store.  This is the address that would have been stored in ar.bsp
501  * if the user had executed a "cover" instruction right before
502  * entering the kernel.  If CFMP is not NULL, it is used to return the
503  * "current frame mask" that was active at the time the kernel was
504  * entered.
505  */
506 unsigned long
507 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
508                        unsigned long *cfmp)
509 {
510         unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
511         long ndirty;
512
513         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
514         bspstore = (unsigned long *) pt->ar_bspstore;
515         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
516
517         if (in_syscall(pt))
518                 ndirty += (cfm & 0x7f);
519         else
520                 cfm &= ~(1UL << 63);    /* clear valid bit */
521
522         if (cfmp)
523                 *cfmp = cfm;
524         return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
525 }
526
527 /*
528  * Synchronize (i.e, write) the RSE backing store living in kernel
529  * space to the VM of the CHILD task.  SW and PT are the pointers to
530  * the switch_stack and pt_regs structures, respectively.
531  * USER_RBS_END is the user-level address at which the backing store
532  * ends.
533  */
534 long
535 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
536                     unsigned long user_rbs_start, unsigned long user_rbs_end)
537 {
538         unsigned long addr, val;
539         long ret;
540
541         /* now copy word for word from kernel rbs to user rbs: */
542         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
543                 ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
544                 if (ret < 0)
545                         return ret;
546                 if (access_process_vm(child, addr, &val, sizeof(val),
547                                 FOLL_FORCE | FOLL_WRITE)
548                     != sizeof(val))
549                         return -EIO;
550         }
551         return 0;
552 }
553
554 static long
555 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
556                 unsigned long user_rbs_start, unsigned long user_rbs_end)
557 {
558         unsigned long addr, val;
559         long ret;
560
561         /* now copy word for word from user rbs to kernel rbs: */
562         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
563                 if (access_process_vm(child, addr, &val, sizeof(val),
564                                 FOLL_FORCE)
565                                 != sizeof(val))
566                         return -EIO;
567
568                 ret = ia64_poke(child, sw, user_rbs_end, addr, val);
569                 if (ret < 0)
570                         return ret;
571         }
572         return 0;
573 }
574
575 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
576                             unsigned long, unsigned long);
577
578 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
579 {
580         struct pt_regs *pt;
581         unsigned long urbs_end;
582         syncfunc_t fn = arg;
583
584         if (unw_unwind_to_user(info) < 0)
585                 return;
586         pt = task_pt_regs(info->task);
587         urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
588
589         fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
590 }
591
592 /*
593  * when a thread is stopped (ptraced), debugger might change thread's user
594  * stack (change memory directly), and we must avoid the RSE stored in kernel
595  * to override user stack (user space's RSE is newer than kernel's in the
596  * case). To workaround the issue, we copy kernel RSE to user RSE before the
597  * task is stopped, so user RSE has updated data.  we then copy user RSE to
598  * kernel after the task is resummed from traced stop and kernel will use the
599  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
600  * synchronize user RSE to kernel.
601  */
602 void ia64_ptrace_stop(void)
603 {
604         if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
605                 return;
606         set_notify_resume(current);
607         unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
608 }
609
610 /*
611  * This is called to read back the register backing store.
612  */
613 void ia64_sync_krbs(void)
614 {
615         clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
616
617         unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
618 }
619
620 /*
621  * After PTRACE_ATTACH, a thread's register backing store area in user
622  * space is assumed to contain correct data whenever the thread is
623  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
624  * But if the child was already stopped for job control when we attach
625  * to it, then it might not ever get into ptrace_stop by the time we
626  * want to examine the user memory containing the RBS.
627  */
628 void
629 ptrace_attach_sync_user_rbs (struct task_struct *child)
630 {
631         int stopped = 0;
632         struct unw_frame_info info;
633
634         /*
635          * If the child is in TASK_STOPPED, we need to change that to
636          * TASK_TRACED momentarily while we operate on it.  This ensures
637          * that the child won't be woken up and return to user mode while
638          * we are doing the sync.  (It can only be woken up for SIGKILL.)
639          */
640
641         read_lock(&tasklist_lock);
642         if (child->sighand) {
643                 spin_lock_irq(&child->sighand->siglock);
644                 if (child->state == TASK_STOPPED &&
645                     !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
646                         set_notify_resume(child);
647
648                         child->state = TASK_TRACED;
649                         stopped = 1;
650                 }
651                 spin_unlock_irq(&child->sighand->siglock);
652         }
653         read_unlock(&tasklist_lock);
654
655         if (!stopped)
656                 return;
657
658         unw_init_from_blocked_task(&info, child);
659         do_sync_rbs(&info, ia64_sync_user_rbs);
660
661         /*
662          * Now move the child back into TASK_STOPPED if it should be in a
663          * job control stop, so that SIGCONT can be used to wake it up.
664          */
665         read_lock(&tasklist_lock);
666         if (child->sighand) {
667                 spin_lock_irq(&child->sighand->siglock);
668                 if (child->state == TASK_TRACED &&
669                     (child->signal->flags & SIGNAL_STOP_STOPPED)) {
670                         child->state = TASK_STOPPED;
671                 }
672                 spin_unlock_irq(&child->sighand->siglock);
673         }
674         read_unlock(&tasklist_lock);
675 }
676
677 /*
678  * Write f32-f127 back to task->thread.fph if it has been modified.
679  */
680 inline void
681 ia64_flush_fph (struct task_struct *task)
682 {
683         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
684
685         /*
686          * Prevent migrating this task while
687          * we're fiddling with the FPU state
688          */
689         preempt_disable();
690         if (ia64_is_local_fpu_owner(task) && psr->mfh) {
691                 psr->mfh = 0;
692                 task->thread.flags |= IA64_THREAD_FPH_VALID;
693                 ia64_save_fpu(&task->thread.fph[0]);
694         }
695         preempt_enable();
696 }
697
698 /*
699  * Sync the fph state of the task so that it can be manipulated
700  * through thread.fph.  If necessary, f32-f127 are written back to
701  * thread.fph or, if the fph state hasn't been used before, thread.fph
702  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
703  * ensure that the task picks up the state from thread.fph when it
704  * executes again.
705  */
706 void
707 ia64_sync_fph (struct task_struct *task)
708 {
709         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
710
711         ia64_flush_fph(task);
712         if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
713                 task->thread.flags |= IA64_THREAD_FPH_VALID;
714                 memset(&task->thread.fph, 0, sizeof(task->thread.fph));
715         }
716         ia64_drop_fpu(task);
717         psr->dfh = 1;
718 }
719
720 /*
721  * Change the machine-state of CHILD such that it will return via the normal
722  * kernel exit-path, rather than the syscall-exit path.
723  */
724 static void
725 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
726                         unsigned long cfm)
727 {
728         struct unw_frame_info info, prev_info;
729         unsigned long ip, sp, pr;
730
731         unw_init_from_blocked_task(&info, child);
732         while (1) {
733                 prev_info = info;
734                 if (unw_unwind(&info) < 0)
735                         return;
736
737                 unw_get_sp(&info, &sp);
738                 if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
739                     < IA64_PT_REGS_SIZE) {
740                         dprintk("ptrace.%s: ran off the top of the kernel "
741                                 "stack\n", __func__);
742                         return;
743                 }
744                 if (unw_get_pr (&prev_info, &pr) < 0) {
745                         unw_get_rp(&prev_info, &ip);
746                         dprintk("ptrace.%s: failed to read "
747                                 "predicate register (ip=0x%lx)\n",
748                                 __func__, ip);
749                         return;
750                 }
751                 if (unw_is_intr_frame(&info)
752                     && (pr & (1UL << PRED_USER_STACK)))
753                         break;
754         }
755
756         /*
757          * Note: at the time of this call, the target task is blocked
758          * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
759          * (aka, "pLvSys") we redirect execution from
760          * .work_pending_syscall_end to .work_processed_kernel.
761          */
762         unw_get_pr(&prev_info, &pr);
763         pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
764         pr |=  (1UL << PRED_NON_SYSCALL);
765         unw_set_pr(&prev_info, pr);
766
767         pt->cr_ifs = (1UL << 63) | cfm;
768         /*
769          * Clear the memory that is NOT written on syscall-entry to
770          * ensure we do not leak kernel-state to user when execution
771          * resumes.
772          */
773         pt->r2 = 0;
774         pt->r3 = 0;
775         pt->r14 = 0;
776         memset(&pt->r16, 0, 16*8);      /* clear r16-r31 */
777         memset(&pt->f6, 0, 6*16);       /* clear f6-f11 */
778         pt->b7 = 0;
779         pt->ar_ccv = 0;
780         pt->ar_csd = 0;
781         pt->ar_ssd = 0;
782 }
783
784 static int
785 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
786                  struct unw_frame_info *info,
787                  unsigned long *data, int write_access)
788 {
789         unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
790         char nat = 0;
791
792         if (write_access) {
793                 nat_bits = *data;
794                 scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
795                 if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
796                         dprintk("ptrace: failed to set ar.unat\n");
797                         return -1;
798                 }
799                 for (regnum = 4; regnum <= 7; ++regnum) {
800                         unw_get_gr(info, regnum, &dummy, &nat);
801                         unw_set_gr(info, regnum, dummy,
802                                    (nat_bits >> regnum) & 1);
803                 }
804         } else {
805                 if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
806                         dprintk("ptrace: failed to read ar.unat\n");
807                         return -1;
808                 }
809                 nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
810                 for (regnum = 4; regnum <= 7; ++regnum) {
811                         unw_get_gr(info, regnum, &dummy, &nat);
812                         nat_bits |= (nat != 0) << regnum;
813                 }
814                 *data = nat_bits;
815         }
816         return 0;
817 }
818
819 static int
820 access_uarea (struct task_struct *child, unsigned long addr,
821               unsigned long *data, int write_access);
822
823 static long
824 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
825 {
826         unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
827         struct unw_frame_info info;
828         struct ia64_fpreg fpval;
829         struct switch_stack *sw;
830         struct pt_regs *pt;
831         long ret, retval = 0;
832         char nat = 0;
833         int i;
834
835         if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
836                 return -EIO;
837
838         pt = task_pt_regs(child);
839         sw = (struct switch_stack *) (child->thread.ksp + 16);
840         unw_init_from_blocked_task(&info, child);
841         if (unw_unwind_to_user(&info) < 0) {
842                 return -EIO;
843         }
844
845         if (((unsigned long) ppr & 0x7) != 0) {
846                 dprintk("ptrace:unaligned register address %p\n", ppr);
847                 return -EIO;
848         }
849
850         if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
851             || access_uarea(child, PT_AR_EC, &ec, 0) < 0
852             || access_uarea(child, PT_AR_LC, &lc, 0) < 0
853             || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
854             || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
855             || access_uarea(child, PT_CFM, &cfm, 0)
856             || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
857                 return -EIO;
858
859         /* control regs */
860
861         retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
862         retval |= __put_user(psr, &ppr->cr_ipsr);
863
864         /* app regs */
865
866         retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
867         retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
868         retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
869         retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
870         retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
871         retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
872
873         retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
874         retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
875         retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
876         retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
877         retval |= __put_user(cfm, &ppr->cfm);
878
879         /* gr1-gr3 */
880
881         retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
882         retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
883
884         /* gr4-gr7 */
885
886         for (i = 4; i < 8; i++) {
887                 if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
888                         return -EIO;
889                 retval |= __put_user(val, &ppr->gr[i]);
890         }
891
892         /* gr8-gr11 */
893
894         retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
895
896         /* gr12-gr15 */
897
898         retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
899         retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
900         retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
901
902         /* gr16-gr31 */
903
904         retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
905
906         /* b0 */
907
908         retval |= __put_user(pt->b0, &ppr->br[0]);
909
910         /* b1-b5 */
911
912         for (i = 1; i < 6; i++) {
913                 if (unw_access_br(&info, i, &val, 0) < 0)
914                         return -EIO;
915                 __put_user(val, &ppr->br[i]);
916         }
917
918         /* b6-b7 */
919
920         retval |= __put_user(pt->b6, &ppr->br[6]);
921         retval |= __put_user(pt->b7, &ppr->br[7]);
922
923         /* fr2-fr5 */
924
925         for (i = 2; i < 6; i++) {
926                 if (unw_get_fr(&info, i, &fpval) < 0)
927                         return -EIO;
928                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
929         }
930
931         /* fr6-fr11 */
932
933         retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
934                                  sizeof(struct ia64_fpreg) * 6);
935
936         /* fp scratch regs(12-15) */
937
938         retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
939                                  sizeof(struct ia64_fpreg) * 4);
940
941         /* fr16-fr31 */
942
943         for (i = 16; i < 32; i++) {
944                 if (unw_get_fr(&info, i, &fpval) < 0)
945                         return -EIO;
946                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
947         }
948
949         /* fph */
950
951         ia64_flush_fph(child);
952         retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
953                                  sizeof(ppr->fr[32]) * 96);
954
955         /*  preds */
956
957         retval |= __put_user(pt->pr, &ppr->pr);
958
959         /* nat bits */
960
961         retval |= __put_user(nat_bits, &ppr->nat);
962
963         ret = retval ? -EIO : 0;
964         return ret;
965 }
966
967 static long
968 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
969 {
970         unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
971         struct unw_frame_info info;
972         struct switch_stack *sw;
973         struct ia64_fpreg fpval;
974         struct pt_regs *pt;
975         long ret, retval = 0;
976         int i;
977
978         memset(&fpval, 0, sizeof(fpval));
979
980         if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
981                 return -EIO;
982
983         pt = task_pt_regs(child);
984         sw = (struct switch_stack *) (child->thread.ksp + 16);
985         unw_init_from_blocked_task(&info, child);
986         if (unw_unwind_to_user(&info) < 0) {
987                 return -EIO;
988         }
989
990         if (((unsigned long) ppr & 0x7) != 0) {
991                 dprintk("ptrace:unaligned register address %p\n", ppr);
992                 return -EIO;
993         }
994
995         /* control regs */
996
997         retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
998         retval |= __get_user(psr, &ppr->cr_ipsr);
999
1000         /* app regs */
1001
1002         retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1003         retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1004         retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1005         retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1006         retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1007         retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1008
1009         retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1010         retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1011         retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1012         retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1013         retval |= __get_user(cfm, &ppr->cfm);
1014
1015         /* gr1-gr3 */
1016
1017         retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1018         retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1019
1020         /* gr4-gr7 */
1021
1022         for (i = 4; i < 8; i++) {
1023                 retval |= __get_user(val, &ppr->gr[i]);
1024                 /* NaT bit will be set via PT_NAT_BITS: */
1025                 if (unw_set_gr(&info, i, val, 0) < 0)
1026                         return -EIO;
1027         }
1028
1029         /* gr8-gr11 */
1030
1031         retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1032
1033         /* gr12-gr15 */
1034
1035         retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1036         retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1037         retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1038
1039         /* gr16-gr31 */
1040
1041         retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1042
1043         /* b0 */
1044
1045         retval |= __get_user(pt->b0, &ppr->br[0]);
1046
1047         /* b1-b5 */
1048
1049         for (i = 1; i < 6; i++) {
1050                 retval |= __get_user(val, &ppr->br[i]);
1051                 unw_set_br(&info, i, val);
1052         }
1053
1054         /* b6-b7 */
1055
1056         retval |= __get_user(pt->b6, &ppr->br[6]);
1057         retval |= __get_user(pt->b7, &ppr->br[7]);
1058
1059         /* fr2-fr5 */
1060
1061         for (i = 2; i < 6; i++) {
1062                 retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1063                 if (unw_set_fr(&info, i, fpval) < 0)
1064                         return -EIO;
1065         }
1066
1067         /* fr6-fr11 */
1068
1069         retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1070                                    sizeof(ppr->fr[6]) * 6);
1071
1072         /* fp scratch regs(12-15) */
1073
1074         retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1075                                    sizeof(ppr->fr[12]) * 4);
1076
1077         /* fr16-fr31 */
1078
1079         for (i = 16; i < 32; i++) {
1080                 retval |= __copy_from_user(&fpval, &ppr->fr[i],
1081                                            sizeof(fpval));
1082                 if (unw_set_fr(&info, i, fpval) < 0)
1083                         return -EIO;
1084         }
1085
1086         /* fph */
1087
1088         ia64_sync_fph(child);
1089         retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1090                                    sizeof(ppr->fr[32]) * 96);
1091
1092         /* preds */
1093
1094         retval |= __get_user(pt->pr, &ppr->pr);
1095
1096         /* nat bits */
1097
1098         retval |= __get_user(nat_bits, &ppr->nat);
1099
1100         retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1101         retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1102         retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1103         retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1104         retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1105         retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1106         retval |= access_uarea(child, PT_CFM, &cfm, 1);
1107         retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1108
1109         ret = retval ? -EIO : 0;
1110         return ret;
1111 }
1112
1113 void
1114 user_enable_single_step (struct task_struct *child)
1115 {
1116         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1117
1118         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1119         child_psr->ss = 1;
1120 }
1121
1122 void
1123 user_enable_block_step (struct task_struct *child)
1124 {
1125         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1126
1127         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1128         child_psr->tb = 1;
1129 }
1130
1131 void
1132 user_disable_single_step (struct task_struct *child)
1133 {
1134         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1135
1136         /* make sure the single step/taken-branch trap bits are not set: */
1137         clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1138         child_psr->ss = 0;
1139         child_psr->tb = 0;
1140 }
1141
1142 /*
1143  * Called by kernel/ptrace.c when detaching..
1144  *
1145  * Make sure the single step bit is not set.
1146  */
1147 void
1148 ptrace_disable (struct task_struct *child)
1149 {
1150         user_disable_single_step(child);
1151 }
1152
1153 long
1154 arch_ptrace (struct task_struct *child, long request,
1155              unsigned long addr, unsigned long data)
1156 {
1157         switch (request) {
1158         case PTRACE_PEEKTEXT:
1159         case PTRACE_PEEKDATA:
1160                 /* read word at location addr */
1161                 if (ptrace_access_vm(child, addr, &data, sizeof(data),
1162                                 FOLL_FORCE)
1163                     != sizeof(data))
1164                         return -EIO;
1165                 /* ensure return value is not mistaken for error code */
1166                 force_successful_syscall_return();
1167                 return data;
1168
1169         /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1170          * by the generic ptrace_request().
1171          */
1172
1173         case PTRACE_PEEKUSR:
1174                 /* read the word at addr in the USER area */
1175                 if (access_uarea(child, addr, &data, 0) < 0)
1176                         return -EIO;
1177                 /* ensure return value is not mistaken for error code */
1178                 force_successful_syscall_return();
1179                 return data;
1180
1181         case PTRACE_POKEUSR:
1182                 /* write the word at addr in the USER area */
1183                 if (access_uarea(child, addr, &data, 1) < 0)
1184                         return -EIO;
1185                 return 0;
1186
1187         case PTRACE_OLD_GETSIGINFO:
1188                 /* for backwards-compatibility */
1189                 return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1190
1191         case PTRACE_OLD_SETSIGINFO:
1192                 /* for backwards-compatibility */
1193                 return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1194
1195         case PTRACE_GETREGS:
1196                 return ptrace_getregs(child,
1197                                       (struct pt_all_user_regs __user *) data);
1198
1199         case PTRACE_SETREGS:
1200                 return ptrace_setregs(child,
1201                                       (struct pt_all_user_regs __user *) data);
1202
1203         default:
1204                 return ptrace_request(child, request, addr, data);
1205         }
1206 }
1207
1208
1209 /* "asmlinkage" so the input arguments are preserved... */
1210
1211 asmlinkage long
1212 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1213                      long arg4, long arg5, long arg6, long arg7,
1214                      struct pt_regs regs)
1215 {
1216         if (test_thread_flag(TIF_SYSCALL_TRACE))
1217                 if (tracehook_report_syscall_entry(&regs))
1218                         return -ENOSYS;
1219
1220         /* copy user rbs to kernel rbs */
1221         if (test_thread_flag(TIF_RESTORE_RSE))
1222                 ia64_sync_krbs();
1223
1224
1225         audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
1226
1227         return 0;
1228 }
1229
1230 /* "asmlinkage" so the input arguments are preserved... */
1231
1232 asmlinkage void
1233 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1234                      long arg4, long arg5, long arg6, long arg7,
1235                      struct pt_regs regs)
1236 {
1237         int step;
1238
1239         audit_syscall_exit(&regs);
1240
1241         step = test_thread_flag(TIF_SINGLESTEP);
1242         if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1243                 tracehook_report_syscall_exit(&regs, step);
1244
1245         /* copy user rbs to kernel rbs */
1246         if (test_thread_flag(TIF_RESTORE_RSE))
1247                 ia64_sync_krbs();
1248 }
1249
1250 /* Utrace implementation starts here */
1251 struct regset_get {
1252         void *kbuf;
1253         void __user *ubuf;
1254 };
1255
1256 struct regset_set {
1257         const void *kbuf;
1258         const void __user *ubuf;
1259 };
1260
1261 struct regset_getset {
1262         struct task_struct *target;
1263         const struct user_regset *regset;
1264         union {
1265                 struct regset_get get;
1266                 struct regset_set set;
1267         } u;
1268         unsigned int pos;
1269         unsigned int count;
1270         int ret;
1271 };
1272
1273 static const ptrdiff_t pt_offsets[32] =
1274 {
1275 #define R(n) offsetof(struct pt_regs, r##n)
1276         [0] = -1, R(1), R(2), R(3),
1277         [4] = -1, [5] = -1, [6] = -1, [7] = -1,
1278         R(8), R(9), R(10), R(11), R(12), R(13), R(14), R(15),
1279         R(16), R(17), R(18), R(19), R(20), R(21), R(22), R(23),
1280         R(24), R(25), R(26), R(27), R(28), R(29), R(30), R(31),
1281 #undef R
1282 };
1283
1284 static int
1285 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1286                 unsigned long addr, unsigned long *data, int write_access)
1287 {
1288         struct pt_regs *pt = task_pt_regs(target);
1289         unsigned reg = addr / sizeof(unsigned long);
1290         ptrdiff_t d = pt_offsets[reg];
1291
1292         if (d >= 0) {
1293                 unsigned long *ptr = (void *)pt + d;
1294                 if (write_access)
1295                         *ptr = *data;
1296                 else
1297                         *data = *ptr;
1298                 return 0;
1299         } else {
1300                 char nat = 0;
1301                 if (write_access) {
1302                         /* read NaT bit first: */
1303                         unsigned long dummy;
1304                         int ret = unw_get_gr(info, reg, &dummy, &nat);
1305                         if (ret < 0)
1306                                 return ret;
1307                 }
1308                 return unw_access_gr(info, reg, data, &nat, write_access);
1309         }
1310 }
1311
1312 static int
1313 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1314                 unsigned long addr, unsigned long *data, int write_access)
1315 {
1316         struct pt_regs *pt;
1317         unsigned long *ptr = NULL;
1318
1319         pt = task_pt_regs(target);
1320         switch (addr) {
1321         case ELF_BR_OFFSET(0):
1322                 ptr = &pt->b0;
1323                 break;
1324         case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1325                 return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1326                                      data, write_access);
1327         case ELF_BR_OFFSET(6):
1328                 ptr = &pt->b6;
1329                 break;
1330         case ELF_BR_OFFSET(7):
1331                 ptr = &pt->b7;
1332         }
1333         if (write_access)
1334                 *ptr = *data;
1335         else
1336                 *data = *ptr;
1337         return 0;
1338 }
1339
1340 static int
1341 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1342                 unsigned long addr, unsigned long *data, int write_access)
1343 {
1344         struct pt_regs *pt;
1345         unsigned long cfm, urbs_end;
1346         unsigned long *ptr = NULL;
1347
1348         pt = task_pt_regs(target);
1349         if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1350                 switch (addr) {
1351                 case ELF_AR_RSC_OFFSET:
1352                         /* force PL3 */
1353                         if (write_access)
1354                                 pt->ar_rsc = *data | (3 << 2);
1355                         else
1356                                 *data = pt->ar_rsc;
1357                         return 0;
1358                 case ELF_AR_BSP_OFFSET:
1359                         /*
1360                          * By convention, we use PT_AR_BSP to refer to
1361                          * the end of the user-level backing store.
1362                          * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1363                          * to get the real value of ar.bsp at the time
1364                          * the kernel was entered.
1365                          *
1366                          * Furthermore, when changing the contents of
1367                          * PT_AR_BSP (or PT_CFM) while the task is
1368                          * blocked in a system call, convert the state
1369                          * so that the non-system-call exit
1370                          * path is used.  This ensures that the proper
1371                          * state will be picked up when resuming
1372                          * execution.  However, it *also* means that
1373                          * once we write PT_AR_BSP/PT_CFM, it won't be
1374                          * possible to modify the syscall arguments of
1375                          * the pending system call any longer.  This
1376                          * shouldn't be an issue because modifying
1377                          * PT_AR_BSP/PT_CFM generally implies that
1378                          * we're either abandoning the pending system
1379                          * call or that we defer it's re-execution
1380                          * (e.g., due to GDB doing an inferior
1381                          * function call).
1382                          */
1383                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1384                         if (write_access) {
1385                                 if (*data != urbs_end) {
1386                                         if (in_syscall(pt))
1387                                                 convert_to_non_syscall(target,
1388                                                                        pt,
1389                                                                        cfm);
1390                                         /*
1391                                          * Simulate user-level write
1392                                          * of ar.bsp:
1393                                          */
1394                                         pt->loadrs = 0;
1395                                         pt->ar_bspstore = *data;
1396                                 }
1397                         } else
1398                                 *data = urbs_end;
1399                         return 0;
1400                 case ELF_AR_BSPSTORE_OFFSET:
1401                         ptr = &pt->ar_bspstore;
1402                         break;
1403                 case ELF_AR_RNAT_OFFSET:
1404                         ptr = &pt->ar_rnat;
1405                         break;
1406                 case ELF_AR_CCV_OFFSET:
1407                         ptr = &pt->ar_ccv;
1408                         break;
1409                 case ELF_AR_UNAT_OFFSET:
1410                         ptr = &pt->ar_unat;
1411                         break;
1412                 case ELF_AR_FPSR_OFFSET:
1413                         ptr = &pt->ar_fpsr;
1414                         break;
1415                 case ELF_AR_PFS_OFFSET:
1416                         ptr = &pt->ar_pfs;
1417                         break;
1418                 case ELF_AR_LC_OFFSET:
1419                         return unw_access_ar(info, UNW_AR_LC, data,
1420                                              write_access);
1421                 case ELF_AR_EC_OFFSET:
1422                         return unw_access_ar(info, UNW_AR_EC, data,
1423                                              write_access);
1424                 case ELF_AR_CSD_OFFSET:
1425                         ptr = &pt->ar_csd;
1426                         break;
1427                 case ELF_AR_SSD_OFFSET:
1428                         ptr = &pt->ar_ssd;
1429                 }
1430         } else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1431                 switch (addr) {
1432                 case ELF_CR_IIP_OFFSET:
1433                         ptr = &pt->cr_iip;
1434                         break;
1435                 case ELF_CFM_OFFSET:
1436                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1437                         if (write_access) {
1438                                 if (((cfm ^ *data) & PFM_MASK) != 0) {
1439                                         if (in_syscall(pt))
1440                                                 convert_to_non_syscall(target,
1441                                                                        pt,
1442                                                                        cfm);
1443                                         pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1444                                                       | (*data & PFM_MASK));
1445                                 }
1446                         } else
1447                                 *data = cfm;
1448                         return 0;
1449                 case ELF_CR_IPSR_OFFSET:
1450                         if (write_access) {
1451                                 unsigned long tmp = *data;
1452                                 /* psr.ri==3 is a reserved value: SDM 2:25 */
1453                                 if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1454                                         tmp &= ~IA64_PSR_RI;
1455                                 pt->cr_ipsr = ((tmp & IPSR_MASK)
1456                                                | (pt->cr_ipsr & ~IPSR_MASK));
1457                         } else
1458                                 *data = (pt->cr_ipsr & IPSR_MASK);
1459                         return 0;
1460                 }
1461         } else if (addr == ELF_NAT_OFFSET)
1462                 return access_nat_bits(target, pt, info,
1463                                        data, write_access);
1464         else if (addr == ELF_PR_OFFSET)
1465                 ptr = &pt->pr;
1466         else
1467                 return -1;
1468
1469         if (write_access)
1470                 *ptr = *data;
1471         else
1472                 *data = *ptr;
1473
1474         return 0;
1475 }
1476
1477 static int
1478 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1479                 unsigned long addr, unsigned long *data, int write_access)
1480 {
1481         if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(31))
1482                 return access_elf_gpreg(target, info, addr, data, write_access);
1483         else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1484                 return access_elf_breg(target, info, addr, data, write_access);
1485         else
1486                 return access_elf_areg(target, info, addr, data, write_access);
1487 }
1488
1489 struct regset_membuf {
1490         struct membuf to;
1491         int ret;
1492 };
1493
1494 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1495 {
1496         struct regset_membuf *dst = arg;
1497         struct membuf to = dst->to;
1498         unsigned int n;
1499         elf_greg_t reg;
1500
1501         if (unw_unwind_to_user(info) < 0)
1502                 return;
1503
1504         /*
1505          * coredump format:
1506          *      r0-r31
1507          *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1508          *      predicate registers (p0-p63)
1509          *      b0-b7
1510          *      ip cfm user-mask
1511          *      ar.rsc ar.bsp ar.bspstore ar.rnat
1512          *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1513          */
1514
1515
1516         /* Skip r0 */
1517         membuf_zero(&to, 8);
1518         for (n = 8; to.left && n < ELF_AR_END_OFFSET; n += 8) {
1519                 if (access_elf_reg(info->task, info, n, &reg, 0) < 0) {
1520                         dst->ret = -EIO;
1521                         return;
1522                 }
1523                 membuf_store(&to, reg);
1524         }
1525 }
1526
1527 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1528 {
1529         struct regset_getset *dst = arg;
1530
1531         if (unw_unwind_to_user(info) < 0)
1532                 return;
1533
1534         if (!dst->count)
1535                 return;
1536         /* Skip r0 */
1537         if (dst->pos < ELF_GR_OFFSET(1)) {
1538                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1539                                                        &dst->u.set.kbuf,
1540                                                        &dst->u.set.ubuf,
1541                                                        0, ELF_GR_OFFSET(1));
1542                 if (dst->ret)
1543                         return;
1544         }
1545
1546         while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
1547                 unsigned int n, from, to;
1548                 elf_greg_t tmp[16];
1549
1550                 from = dst->pos;
1551                 to = from + sizeof(tmp);
1552                 if (to > ELF_AR_END_OFFSET)
1553                         to = ELF_AR_END_OFFSET;
1554                 /* get up to 16 values */
1555                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1556                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1557                                 from, to);
1558                 if (dst->ret)
1559                         return;
1560                 /* now copy them into registers */
1561                 for (n = 0; from < dst->pos; from += sizeof(elf_greg_t), n++)
1562                         if (access_elf_reg(dst->target, info, from,
1563                                                 &tmp[n], 1) < 0) {
1564                                 dst->ret = -EIO;
1565                                 return;
1566                         }
1567         }
1568 }
1569
1570 #define ELF_FP_OFFSET(i)        (i * sizeof(elf_fpreg_t))
1571
1572 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1573 {
1574         struct task_struct *task = info->task;
1575         struct regset_membuf *dst = arg;
1576         struct membuf to = dst->to;
1577         elf_fpreg_t reg;
1578         unsigned int n;
1579
1580         if (unw_unwind_to_user(info) < 0)
1581                 return;
1582
1583         /* Skip pos 0 and 1 */
1584         membuf_zero(&to, 2 * sizeof(elf_fpreg_t));
1585
1586         /* fr2-fr31 */
1587         for (n = 2; to.left && n < 32; n++) {
1588                 if (unw_get_fr(info, n, &reg)) {
1589                         dst->ret = -EIO;
1590                         return;
1591                 }
1592                 membuf_write(&to, &reg, sizeof(reg));
1593         }
1594
1595         /* fph */
1596         if (!to.left)
1597                 return;
1598
1599         ia64_flush_fph(task);
1600         if (task->thread.flags & IA64_THREAD_FPH_VALID)
1601                 membuf_write(&to, &task->thread.fph, 96 * sizeof(reg));
1602         else
1603                 membuf_zero(&to, 96 * sizeof(reg));
1604 }
1605
1606 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1607 {
1608         struct regset_getset *dst = arg;
1609         elf_fpreg_t fpreg, tmp[30];
1610         int index, start, end;
1611
1612         if (unw_unwind_to_user(info) < 0)
1613                 return;
1614
1615         /* Skip pos 0 and 1 */
1616         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1617                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1618                                                        &dst->u.set.kbuf,
1619                                                        &dst->u.set.ubuf,
1620                                                        0, ELF_FP_OFFSET(2));
1621                 if (dst->count == 0 || dst->ret)
1622                         return;
1623         }
1624
1625         /* fr2-fr31 */
1626         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1627                 start = dst->pos;
1628                 end = min(((unsigned int)ELF_FP_OFFSET(32)),
1629                          dst->pos + dst->count);
1630                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1631                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1632                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1633                 if (dst->ret)
1634                         return;
1635
1636                 if (start & 0xF) { /* only write high part */
1637                         if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1638                                          &fpreg)) {
1639                                 dst->ret = -EIO;
1640                                 return;
1641                         }
1642                         tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1643                                 = fpreg.u.bits[0];
1644                         start &= ~0xFUL;
1645                 }
1646                 if (end & 0xF) { /* only write low part */
1647                         if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1648                                         &fpreg)) {
1649                                 dst->ret = -EIO;
1650                                 return;
1651                         }
1652                         tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1653                                 = fpreg.u.bits[1];
1654                         end = (end + 0xF) & ~0xFUL;
1655                 }
1656
1657                 for ( ; start < end ; start += sizeof(elf_fpreg_t)) {
1658                         index = start / sizeof(elf_fpreg_t);
1659                         if (unw_set_fr(info, index, tmp[index - 2])) {
1660                                 dst->ret = -EIO;
1661                                 return;
1662                         }
1663                 }
1664                 if (dst->ret || dst->count == 0)
1665                         return;
1666         }
1667
1668         /* fph */
1669         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1670                 ia64_sync_fph(dst->target);
1671                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1672                                                 &dst->u.set.kbuf,
1673                                                 &dst->u.set.ubuf,
1674                                                 &dst->target->thread.fph,
1675                                                 ELF_FP_OFFSET(32), -1);
1676         }
1677 }
1678
1679 static void
1680 unwind_and_call(void (*call)(struct unw_frame_info *, void *),
1681                struct task_struct *target, void *data)
1682 {
1683         if (target == current)
1684                 unw_init_running(call, data);
1685         else {
1686                 struct unw_frame_info info;
1687                 memset(&info, 0, sizeof(info));
1688                 unw_init_from_blocked_task(&info, target);
1689                 (*call)(&info, data);
1690         }
1691 }
1692
1693 static int
1694 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1695                struct task_struct *target,
1696                const struct user_regset *regset,
1697                unsigned int pos, unsigned int count,
1698                const void *kbuf, const void __user *ubuf)
1699 {
1700         struct regset_getset info = { .target = target, .regset = regset,
1701                                  .pos = pos, .count = count,
1702                                  .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1703                                  .ret = 0 };
1704         unwind_and_call(call, target, &info);
1705         return info.ret;
1706 }
1707
1708 static int
1709 gpregs_get(struct task_struct *target,
1710            const struct user_regset *regset,
1711            struct membuf to)
1712 {
1713         struct regset_membuf info = {.to = to};
1714         unwind_and_call(do_gpregs_get, target, &info);
1715         return info.ret;
1716 }
1717
1718 static int gpregs_set(struct task_struct *target,
1719                 const struct user_regset *regset,
1720                 unsigned int pos, unsigned int count,
1721                 const void *kbuf, const void __user *ubuf)
1722 {
1723         return do_regset_call(do_gpregs_set, target, regset, pos, count,
1724                 kbuf, ubuf);
1725 }
1726
1727 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1728 {
1729         do_sync_rbs(info, ia64_sync_user_rbs);
1730 }
1731
1732 /*
1733  * This is called to write back the register backing store.
1734  * ptrace does this before it stops, so that a tracer reading the user
1735  * memory after the thread stops will get the current register data.
1736  */
1737 static int
1738 gpregs_writeback(struct task_struct *target,
1739                  const struct user_regset *regset,
1740                  int now)
1741 {
1742         if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1743                 return 0;
1744         set_notify_resume(target);
1745         return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1746                 NULL, NULL);
1747 }
1748
1749 static int
1750 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1751 {
1752         return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1753 }
1754
1755 static int fpregs_get(struct task_struct *target,
1756                 const struct user_regset *regset,
1757                 struct membuf to)
1758 {
1759         struct regset_membuf info = {.to = to};
1760         unwind_and_call(do_fpregs_get, target, &info);
1761         return info.ret;
1762 }
1763
1764 static int fpregs_set(struct task_struct *target,
1765                 const struct user_regset *regset,
1766                 unsigned int pos, unsigned int count,
1767                 const void *kbuf, const void __user *ubuf)
1768 {
1769         return do_regset_call(do_fpregs_set, target, regset, pos, count,
1770                 kbuf, ubuf);
1771 }
1772
1773 static int
1774 access_uarea(struct task_struct *child, unsigned long addr,
1775               unsigned long *data, int write_access)
1776 {
1777         unsigned int pos = -1; /* an invalid value */
1778         unsigned long *ptr, regnum;
1779
1780         if ((addr & 0x7) != 0) {
1781                 dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1782                 return -1;
1783         }
1784         if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1785                 (addr >= PT_R7 + 8 && addr < PT_B1) ||
1786                 (addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1787                 (addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1788                 dprintk("ptrace: rejecting access to register "
1789                                         "address 0x%lx\n", addr);
1790                 return -1;
1791         }
1792
1793         switch (addr) {
1794         case PT_F32 ... (PT_F127 + 15):
1795                 pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1796                 break;
1797         case PT_F2 ... (PT_F5 + 15):
1798                 pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1799                 break;
1800         case PT_F10 ... (PT_F31 + 15):
1801                 pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1802                 break;
1803         case PT_F6 ... (PT_F9 + 15):
1804                 pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1805                 break;
1806         }
1807
1808         if (pos != -1) {
1809                 unsigned reg = pos / sizeof(elf_fpreg_t);
1810                 int which_half = (pos / sizeof(unsigned long)) & 1;
1811
1812                 if (reg < 32) { /* fr2-fr31 */
1813                         struct unw_frame_info info;
1814                         elf_fpreg_t fpreg;
1815
1816                         memset(&info, 0, sizeof(info));
1817                         unw_init_from_blocked_task(&info, child);
1818                         if (unw_unwind_to_user(&info) < 0)
1819                                 return 0;
1820
1821                         if (unw_get_fr(&info, reg, &fpreg))
1822                                 return -1;
1823                         if (write_access) {
1824                                 fpreg.u.bits[which_half] = *data;
1825                                 if (unw_set_fr(&info, reg, fpreg))
1826                                         return -1;
1827                         } else {
1828                                 *data = fpreg.u.bits[which_half];
1829                         }
1830                 } else { /* fph */
1831                         elf_fpreg_t *p = &child->thread.fph[reg - 32];
1832                         unsigned long *bits = &p->u.bits[which_half];
1833
1834                         ia64_sync_fph(child);
1835                         if (write_access)
1836                                 *bits = *data;
1837                         else if (child->thread.flags & IA64_THREAD_FPH_VALID)
1838                                 *data = *bits;
1839                         else
1840                                 *data = 0;
1841                 }
1842                 return 0;
1843         }
1844
1845         switch (addr) {
1846         case PT_NAT_BITS:
1847                 pos = ELF_NAT_OFFSET;
1848                 break;
1849         case PT_R4 ... PT_R7:
1850                 pos = addr - PT_R4 + ELF_GR_OFFSET(4);
1851                 break;
1852         case PT_B1 ... PT_B5:
1853                 pos = addr - PT_B1 + ELF_BR_OFFSET(1);
1854                 break;
1855         case PT_AR_EC:
1856                 pos = ELF_AR_EC_OFFSET;
1857                 break;
1858         case PT_AR_LC:
1859                 pos = ELF_AR_LC_OFFSET;
1860                 break;
1861         case PT_CR_IPSR:
1862                 pos = ELF_CR_IPSR_OFFSET;
1863                 break;
1864         case PT_CR_IIP:
1865                 pos = ELF_CR_IIP_OFFSET;
1866                 break;
1867         case PT_CFM:
1868                 pos = ELF_CFM_OFFSET;
1869                 break;
1870         case PT_AR_UNAT:
1871                 pos = ELF_AR_UNAT_OFFSET;
1872                 break;
1873         case PT_AR_PFS:
1874                 pos = ELF_AR_PFS_OFFSET;
1875                 break;
1876         case PT_AR_RSC:
1877                 pos = ELF_AR_RSC_OFFSET;
1878                 break;
1879         case PT_AR_RNAT:
1880                 pos = ELF_AR_RNAT_OFFSET;
1881                 break;
1882         case PT_AR_BSPSTORE:
1883                 pos = ELF_AR_BSPSTORE_OFFSET;
1884                 break;
1885         case PT_PR:
1886                 pos = ELF_PR_OFFSET;
1887                 break;
1888         case PT_B6:
1889                 pos = ELF_BR_OFFSET(6);
1890                 break;
1891         case PT_AR_BSP:
1892                 pos = ELF_AR_BSP_OFFSET;
1893                 break;
1894         case PT_R1 ... PT_R3:
1895                 pos = addr - PT_R1 + ELF_GR_OFFSET(1);
1896                 break;
1897         case PT_R12 ... PT_R15:
1898                 pos = addr - PT_R12 + ELF_GR_OFFSET(12);
1899                 break;
1900         case PT_R8 ... PT_R11:
1901                 pos = addr - PT_R8 + ELF_GR_OFFSET(8);
1902                 break;
1903         case PT_R16 ... PT_R31:
1904                 pos = addr - PT_R16 + ELF_GR_OFFSET(16);
1905                 break;
1906         case PT_AR_CCV:
1907                 pos = ELF_AR_CCV_OFFSET;
1908                 break;
1909         case PT_AR_FPSR:
1910                 pos = ELF_AR_FPSR_OFFSET;
1911                 break;
1912         case PT_B0:
1913                 pos = ELF_BR_OFFSET(0);
1914                 break;
1915         case PT_B7:
1916                 pos = ELF_BR_OFFSET(7);
1917                 break;
1918         case PT_AR_CSD:
1919                 pos = ELF_AR_CSD_OFFSET;
1920                 break;
1921         case PT_AR_SSD:
1922                 pos = ELF_AR_SSD_OFFSET;
1923                 break;
1924         }
1925
1926         if (pos != -1) {
1927                 struct unw_frame_info info;
1928
1929                 memset(&info, 0, sizeof(info));
1930                 unw_init_from_blocked_task(&info, child);
1931                 if (unw_unwind_to_user(&info) < 0)
1932                         return 0;
1933
1934                 return access_elf_reg(child, &info, pos, data, write_access);
1935         }
1936
1937         /* access debug registers */
1938         if (addr >= PT_IBR) {
1939                 regnum = (addr - PT_IBR) >> 3;
1940                 ptr = &child->thread.ibr[0];
1941         } else {
1942                 regnum = (addr - PT_DBR) >> 3;
1943                 ptr = &child->thread.dbr[0];
1944         }
1945
1946         if (regnum >= 8) {
1947                 dprintk("ptrace: rejecting access to register "
1948                                 "address 0x%lx\n", addr);
1949                 return -1;
1950         }
1951
1952         if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
1953                 child->thread.flags |= IA64_THREAD_DBG_VALID;
1954                 memset(child->thread.dbr, 0,
1955                                 sizeof(child->thread.dbr));
1956                 memset(child->thread.ibr, 0,
1957                                 sizeof(child->thread.ibr));
1958         }
1959
1960         ptr += regnum;
1961
1962         if ((regnum & 1) && write_access) {
1963                 /* don't let the user set kernel-level breakpoints: */
1964                 *ptr = *data & ~(7UL << 56);
1965                 return 0;
1966         }
1967         if (write_access)
1968                 *ptr = *data;
1969         else
1970                 *data = *ptr;
1971         return 0;
1972 }
1973
1974 static const struct user_regset native_regsets[] = {
1975         {
1976                 .core_note_type = NT_PRSTATUS,
1977                 .n = ELF_NGREG,
1978                 .size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
1979                 .regset_get = gpregs_get, .set = gpregs_set,
1980                 .writeback = gpregs_writeback
1981         },
1982         {
1983                 .core_note_type = NT_PRFPREG,
1984                 .n = ELF_NFPREG,
1985                 .size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
1986                 .regset_get = fpregs_get, .set = fpregs_set, .active = fpregs_active
1987         },
1988 };
1989
1990 static const struct user_regset_view user_ia64_view = {
1991         .name = "ia64",
1992         .e_machine = EM_IA_64,
1993         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
1994 };
1995
1996 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
1997 {
1998         return &user_ia64_view;
1999 }
2000
2001 struct syscall_get_set_args {
2002         unsigned int i;
2003         unsigned int n;
2004         unsigned long *args;
2005         struct pt_regs *regs;
2006         int rw;
2007 };
2008
2009 static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2010 {
2011         struct syscall_get_set_args *args = data;
2012         struct pt_regs *pt = args->regs;
2013         unsigned long *krbs, cfm, ndirty, nlocals, nouts;
2014         int i, count;
2015
2016         if (unw_unwind_to_user(info) < 0)
2017                 return;
2018
2019         /*
2020          * We get here via a few paths:
2021          * - break instruction: cfm is shared with caller.
2022          *   syscall args are in out= regs, locals are non-empty.
2023          * - epsinstruction: cfm is set by br.call
2024          *   locals don't exist.
2025          *
2026          * For both cases argguments are reachable in cfm.sof - cfm.sol.
2027          * CFM: [ ... | sor: 17..14 | sol : 13..7 | sof : 6..0 ]
2028          */
2029         cfm = pt->cr_ifs;
2030         nlocals = (cfm >> 7) & 0x7f; /* aka sol */
2031         nouts = (cfm & 0x7f) - nlocals; /* aka sof - sol */
2032         krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2033         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2034
2035         count = 0;
2036         if (in_syscall(pt))
2037                 count = min_t(int, args->n, nouts);
2038
2039         /* Iterate over outs. */
2040         for (i = 0; i < count; i++) {
2041                 int j = ndirty + nlocals + i + args->i;
2042                 if (args->rw)
2043                         *ia64_rse_skip_regs(krbs, j) = args->args[i];
2044                 else
2045                         args->args[i] = *ia64_rse_skip_regs(krbs, j);
2046         }
2047
2048         if (!args->rw) {
2049                 while (i < args->n) {
2050                         args->args[i] = 0;
2051                         i++;
2052                 }
2053         }
2054 }
2055
2056 void ia64_syscall_get_set_arguments(struct task_struct *task,
2057         struct pt_regs *regs, unsigned long *args, int rw)
2058 {
2059         struct syscall_get_set_args data = {
2060                 .i = 0,
2061                 .n = 6,
2062                 .args = args,
2063                 .regs = regs,
2064                 .rw = rw,
2065         };
2066
2067         if (task == current)
2068                 unw_init_running(syscall_get_set_args_cb, &data);
2069         else {
2070                 struct unw_frame_info ufi;
2071                 memset(&ufi, 0, sizeof(ufi));
2072                 unw_init_from_blocked_task(&ufi, task);
2073                 syscall_get_set_args_cb(&ufi, &data);
2074         }
2075 }