[IPV4]: Correct rp_filter help text.
[linux-2.6/verdex.git] / arch / ia64 / kernel / ptrace.c
blob00f80324694829f5eef2e647299a8227213689f1
1 /*
2 * Kernel support for the ptrace() and syscall tracing interfaces.
4 * Copyright (C) 1999-2005 Hewlett-Packard Co
5 * David Mosberger-Tang <davidm@hpl.hp.com>
7 * Derived from the x86 and Alpha versions.
8 */
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/mm.h>
13 #include <linux/errno.h>
14 #include <linux/ptrace.h>
15 #include <linux/smp_lock.h>
16 #include <linux/user.h>
17 #include <linux/security.h>
18 #include <linux/audit.h>
19 #include <linux/signal.h>
21 #include <asm/pgtable.h>
22 #include <asm/processor.h>
23 #include <asm/ptrace_offsets.h>
24 #include <asm/rse.h>
25 #include <asm/system.h>
26 #include <asm/uaccess.h>
27 #include <asm/unwind.h>
28 #ifdef CONFIG_PERFMON
29 #include <asm/perfmon.h>
30 #endif
32 #include "entry.h"
35 * Bits in the PSR that we allow ptrace() to change:
36 * be, up, ac, mfl, mfh (the user mask; five bits total)
37 * db (debug breakpoint fault; one bit)
38 * id (instruction debug fault disable; one bit)
39 * dd (data debug fault disable; one bit)
40 * ri (restart instruction; two bits)
41 * is (instruction set; one bit)
43 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS \
44 | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
46 #define MASK(nbits) ((1UL << (nbits)) - 1) /* mask with NBITS bits set */
47 #define PFM_MASK MASK(38)
49 #define PTRACE_DEBUG 0
51 #if PTRACE_DEBUG
52 # define dprintk(format...) printk(format)
53 # define inline
54 #else
55 # define dprintk(format...)
56 #endif
58 /* Return TRUE if PT was created due to kernel-entry via a system-call. */
60 static inline int
61 in_syscall (struct pt_regs *pt)
63 return (long) pt->cr_ifs >= 0;
67 * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
68 * bitset where bit i is set iff the NaT bit of register i is set.
70 unsigned long
71 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
73 # define GET_BITS(first, last, unat) \
74 ({ \
75 unsigned long bit = ia64_unat_pos(&pt->r##first); \
76 unsigned long nbits = (last - first + 1); \
77 unsigned long mask = MASK(nbits) << first; \
78 unsigned long dist; \
79 if (bit < first) \
80 dist = 64 + bit - first; \
81 else \
82 dist = bit - first; \
83 ia64_rotr(unat, dist) & mask; \
85 unsigned long val;
88 * Registers that are stored consecutively in struct pt_regs
89 * can be handled in parallel. If the register order in
90 * struct_pt_regs changes, this code MUST be updated.
92 val = GET_BITS( 1, 1, scratch_unat);
93 val |= GET_BITS( 2, 3, scratch_unat);
94 val |= GET_BITS(12, 13, scratch_unat);
95 val |= GET_BITS(14, 14, scratch_unat);
96 val |= GET_BITS(15, 15, scratch_unat);
97 val |= GET_BITS( 8, 11, scratch_unat);
98 val |= GET_BITS(16, 31, scratch_unat);
99 return val;
101 # undef GET_BITS
105 * Set the NaT bits for the scratch registers according to NAT and
106 * return the resulting unat (assuming the scratch registers are
107 * stored in PT).
109 unsigned long
110 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
112 # define PUT_BITS(first, last, nat) \
113 ({ \
114 unsigned long bit = ia64_unat_pos(&pt->r##first); \
115 unsigned long nbits = (last - first + 1); \
116 unsigned long mask = MASK(nbits) << first; \
117 long dist; \
118 if (bit < first) \
119 dist = 64 + bit - first; \
120 else \
121 dist = bit - first; \
122 ia64_rotl(nat & mask, dist); \
124 unsigned long scratch_unat;
127 * Registers that are stored consecutively in struct pt_regs
128 * can be handled in parallel. If the register order in
129 * struct_pt_regs changes, this code MUST be updated.
131 scratch_unat = PUT_BITS( 1, 1, nat);
132 scratch_unat |= PUT_BITS( 2, 3, nat);
133 scratch_unat |= PUT_BITS(12, 13, nat);
134 scratch_unat |= PUT_BITS(14, 14, nat);
135 scratch_unat |= PUT_BITS(15, 15, nat);
136 scratch_unat |= PUT_BITS( 8, 11, nat);
137 scratch_unat |= PUT_BITS(16, 31, nat);
139 return scratch_unat;
141 # undef PUT_BITS
144 #define IA64_MLX_TEMPLATE 0x2
145 #define IA64_MOVL_OPCODE 6
147 void
148 ia64_increment_ip (struct pt_regs *regs)
150 unsigned long w0, ri = ia64_psr(regs)->ri + 1;
152 if (ri > 2) {
153 ri = 0;
154 regs->cr_iip += 16;
155 } else if (ri == 2) {
156 get_user(w0, (char __user *) regs->cr_iip + 0);
157 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
159 * rfi'ing to slot 2 of an MLX bundle causes
160 * an illegal operation fault. We don't want
161 * that to happen...
163 ri = 0;
164 regs->cr_iip += 16;
167 ia64_psr(regs)->ri = ri;
170 void
171 ia64_decrement_ip (struct pt_regs *regs)
173 unsigned long w0, ri = ia64_psr(regs)->ri - 1;
175 if (ia64_psr(regs)->ri == 0) {
176 regs->cr_iip -= 16;
177 ri = 2;
178 get_user(w0, (char __user *) regs->cr_iip + 0);
179 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
181 * rfi'ing to slot 2 of an MLX bundle causes
182 * an illegal operation fault. We don't want
183 * that to happen...
185 ri = 1;
188 ia64_psr(regs)->ri = ri;
192 * This routine is used to read an rnat bits that are stored on the
193 * kernel backing store. Since, in general, the alignment of the user
194 * and kernel are different, this is not completely trivial. In
195 * essence, we need to construct the user RNAT based on up to two
196 * kernel RNAT values and/or the RNAT value saved in the child's
197 * pt_regs.
199 * user rbs
201 * +--------+ <-- lowest address
202 * | slot62 |
203 * +--------+
204 * | rnat | 0x....1f8
205 * +--------+
206 * | slot00 | \
207 * +--------+ |
208 * | slot01 | > child_regs->ar_rnat
209 * +--------+ |
210 * | slot02 | / kernel rbs
211 * +--------+ +--------+
212 * <- child_regs->ar_bspstore | slot61 | <-- krbs
213 * +- - - - + +--------+
214 * | slot62 |
215 * +- - - - + +--------+
216 * | rnat |
217 * +- - - - + +--------+
218 * vrnat | slot00 |
219 * +- - - - + +--------+
220 * = =
221 * +--------+
222 * | slot00 | \
223 * +--------+ |
224 * | slot01 | > child_stack->ar_rnat
225 * +--------+ |
226 * | slot02 | /
227 * +--------+
228 * <--- child_stack->ar_bspstore
230 * The way to think of this code is as follows: bit 0 in the user rnat
231 * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
232 * value. The kernel rnat value holding this bit is stored in
233 * variable rnat0. rnat1 is loaded with the kernel rnat value that
234 * form the upper bits of the user rnat value.
236 * Boundary cases:
238 * o when reading the rnat "below" the first rnat slot on the kernel
239 * backing store, rnat0/rnat1 are set to 0 and the low order bits are
240 * merged in from pt->ar_rnat.
242 * o when reading the rnat "above" the last rnat slot on the kernel
243 * backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
245 static unsigned long
246 get_rnat (struct task_struct *task, struct switch_stack *sw,
247 unsigned long *krbs, unsigned long *urnat_addr,
248 unsigned long *urbs_end)
250 unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
251 unsigned long umask = 0, mask, m;
252 unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
253 long num_regs, nbits;
254 struct pt_regs *pt;
256 pt = task_pt_regs(task);
257 kbsp = (unsigned long *) sw->ar_bspstore;
258 ubspstore = (unsigned long *) pt->ar_bspstore;
260 if (urbs_end < urnat_addr)
261 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
262 else
263 nbits = 63;
264 mask = MASK(nbits);
266 * First, figure out which bit number slot 0 in user-land maps
267 * to in the kernel rnat. Do this by figuring out how many
268 * register slots we're beyond the user's backingstore and
269 * then computing the equivalent address in kernel space.
271 num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
272 slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
273 shift = ia64_rse_slot_num(slot0_kaddr);
274 rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
275 rnat0_kaddr = rnat1_kaddr - 64;
277 if (ubspstore + 63 > urnat_addr) {
278 /* some bits need to be merged in from pt->ar_rnat */
279 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
280 urnat = (pt->ar_rnat & umask);
281 mask &= ~umask;
282 if (!mask)
283 return urnat;
286 m = mask << shift;
287 if (rnat0_kaddr >= kbsp)
288 rnat0 = sw->ar_rnat;
289 else if (rnat0_kaddr > krbs)
290 rnat0 = *rnat0_kaddr;
291 urnat |= (rnat0 & m) >> shift;
293 m = mask >> (63 - shift);
294 if (rnat1_kaddr >= kbsp)
295 rnat1 = sw->ar_rnat;
296 else if (rnat1_kaddr > krbs)
297 rnat1 = *rnat1_kaddr;
298 urnat |= (rnat1 & m) << (63 - shift);
299 return urnat;
303 * The reverse of get_rnat.
305 static void
306 put_rnat (struct task_struct *task, struct switch_stack *sw,
307 unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
308 unsigned long *urbs_end)
310 unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
311 unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
312 long num_regs, nbits;
313 struct pt_regs *pt;
314 unsigned long cfm, *urbs_kargs;
316 pt = task_pt_regs(task);
317 kbsp = (unsigned long *) sw->ar_bspstore;
318 ubspstore = (unsigned long *) pt->ar_bspstore;
320 urbs_kargs = urbs_end;
321 if (in_syscall(pt)) {
323 * If entered via syscall, don't allow user to set rnat bits
324 * for syscall args.
326 cfm = pt->cr_ifs;
327 urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
330 if (urbs_kargs >= urnat_addr)
331 nbits = 63;
332 else {
333 if ((urnat_addr - 63) >= urbs_kargs)
334 return;
335 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
337 mask = MASK(nbits);
340 * First, figure out which bit number slot 0 in user-land maps
341 * to in the kernel rnat. Do this by figuring out how many
342 * register slots we're beyond the user's backingstore and
343 * then computing the equivalent address in kernel space.
345 num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
346 slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
347 shift = ia64_rse_slot_num(slot0_kaddr);
348 rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
349 rnat0_kaddr = rnat1_kaddr - 64;
351 if (ubspstore + 63 > urnat_addr) {
352 /* some bits need to be place in pt->ar_rnat: */
353 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
354 pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
355 mask &= ~umask;
356 if (!mask)
357 return;
360 * Note: Section 11.1 of the EAS guarantees that bit 63 of an
361 * rnat slot is ignored. so we don't have to clear it here.
363 rnat0 = (urnat << shift);
364 m = mask << shift;
365 if (rnat0_kaddr >= kbsp)
366 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
367 else if (rnat0_kaddr > krbs)
368 *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
370 rnat1 = (urnat >> (63 - shift));
371 m = mask >> (63 - shift);
372 if (rnat1_kaddr >= kbsp)
373 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
374 else if (rnat1_kaddr > krbs)
375 *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
378 static inline int
379 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
380 unsigned long urbs_end)
382 unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
383 urbs_end);
384 return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
388 * Read a word from the user-level backing store of task CHILD. ADDR
389 * is the user-level address to read the word from, VAL a pointer to
390 * the return value, and USER_BSP gives the end of the user-level
391 * backing store (i.e., it's the address that would be in ar.bsp after
392 * the user executed a "cover" instruction).
394 * This routine takes care of accessing the kernel register backing
395 * store for those registers that got spilled there. It also takes
396 * care of calculating the appropriate RNaT collection words.
398 long
399 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
400 unsigned long user_rbs_end, unsigned long addr, long *val)
402 unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
403 struct pt_regs *child_regs;
404 size_t copied;
405 long ret;
407 urbs_end = (long *) user_rbs_end;
408 laddr = (unsigned long *) addr;
409 child_regs = task_pt_regs(child);
410 bspstore = (unsigned long *) child_regs->ar_bspstore;
411 krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
412 if (on_kernel_rbs(addr, (unsigned long) bspstore,
413 (unsigned long) urbs_end))
416 * Attempt to read the RBS in an area that's actually
417 * on the kernel RBS => read the corresponding bits in
418 * the kernel RBS.
420 rnat_addr = ia64_rse_rnat_addr(laddr);
421 ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
423 if (laddr == rnat_addr) {
424 /* return NaT collection word itself */
425 *val = ret;
426 return 0;
429 if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
431 * It is implementation dependent whether the
432 * data portion of a NaT value gets saved on a
433 * st8.spill or RSE spill (e.g., see EAS 2.6,
434 * 4.4.4.6 Register Spill and Fill). To get
435 * consistent behavior across all possible
436 * IA-64 implementations, we return zero in
437 * this case.
439 *val = 0;
440 return 0;
443 if (laddr < urbs_end) {
445 * The desired word is on the kernel RBS and
446 * is not a NaT.
448 regnum = ia64_rse_num_regs(bspstore, laddr);
449 *val = *ia64_rse_skip_regs(krbs, regnum);
450 return 0;
453 copied = access_process_vm(child, addr, &ret, sizeof(ret), 0);
454 if (copied != sizeof(ret))
455 return -EIO;
456 *val = ret;
457 return 0;
460 long
461 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
462 unsigned long user_rbs_end, unsigned long addr, long val)
464 unsigned long *bspstore, *krbs, regnum, *laddr;
465 unsigned long *urbs_end = (long *) user_rbs_end;
466 struct pt_regs *child_regs;
468 laddr = (unsigned long *) addr;
469 child_regs = task_pt_regs(child);
470 bspstore = (unsigned long *) child_regs->ar_bspstore;
471 krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
472 if (on_kernel_rbs(addr, (unsigned long) bspstore,
473 (unsigned long) urbs_end))
476 * Attempt to write the RBS in an area that's actually
477 * on the kernel RBS => write the corresponding bits
478 * in the kernel RBS.
480 if (ia64_rse_is_rnat_slot(laddr))
481 put_rnat(child, child_stack, krbs, laddr, val,
482 urbs_end);
483 else {
484 if (laddr < urbs_end) {
485 regnum = ia64_rse_num_regs(bspstore, laddr);
486 *ia64_rse_skip_regs(krbs, regnum) = val;
489 } else if (access_process_vm(child, addr, &val, sizeof(val), 1)
490 != sizeof(val))
491 return -EIO;
492 return 0;
496 * Calculate the address of the end of the user-level register backing
497 * store. This is the address that would have been stored in ar.bsp
498 * if the user had executed a "cover" instruction right before
499 * entering the kernel. If CFMP is not NULL, it is used to return the
500 * "current frame mask" that was active at the time the kernel was
501 * entered.
503 unsigned long
504 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
505 unsigned long *cfmp)
507 unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
508 long ndirty;
510 krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
511 bspstore = (unsigned long *) pt->ar_bspstore;
512 ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
514 if (in_syscall(pt))
515 ndirty += (cfm & 0x7f);
516 else
517 cfm &= ~(1UL << 63); /* clear valid bit */
519 if (cfmp)
520 *cfmp = cfm;
521 return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
525 * Synchronize (i.e, write) the RSE backing store living in kernel
526 * space to the VM of the CHILD task. SW and PT are the pointers to
527 * the switch_stack and pt_regs structures, respectively.
528 * USER_RBS_END is the user-level address at which the backing store
529 * ends.
531 long
532 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
533 unsigned long user_rbs_start, unsigned long user_rbs_end)
535 unsigned long addr, val;
536 long ret;
538 /* now copy word for word from kernel rbs to user rbs: */
539 for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
540 ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
541 if (ret < 0)
542 return ret;
543 if (access_process_vm(child, addr, &val, sizeof(val), 1)
544 != sizeof(val))
545 return -EIO;
547 return 0;
550 static inline int
551 thread_matches (struct task_struct *thread, unsigned long addr)
553 unsigned long thread_rbs_end;
554 struct pt_regs *thread_regs;
556 if (ptrace_check_attach(thread, 0) < 0)
558 * If the thread is not in an attachable state, we'll
559 * ignore it. The net effect is that if ADDR happens
560 * to overlap with the portion of the thread's
561 * register backing store that is currently residing
562 * on the thread's kernel stack, then ptrace() may end
563 * up accessing a stale value. But if the thread
564 * isn't stopped, that's a problem anyhow, so we're
565 * doing as well as we can...
567 return 0;
569 thread_regs = task_pt_regs(thread);
570 thread_rbs_end = ia64_get_user_rbs_end(thread, thread_regs, NULL);
571 if (!on_kernel_rbs(addr, thread_regs->ar_bspstore, thread_rbs_end))
572 return 0;
574 return 1; /* looks like we've got a winner */
578 * GDB apparently wants to be able to read the register-backing store
579 * of any thread when attached to a given process. If we are peeking
580 * or poking an address that happens to reside in the kernel-backing
581 * store of another thread, we need to attach to that thread, because
582 * otherwise we end up accessing stale data.
584 * task_list_lock must be read-locked before calling this routine!
586 static struct task_struct *
587 find_thread_for_addr (struct task_struct *child, unsigned long addr)
589 struct task_struct *p;
590 struct mm_struct *mm;
591 struct list_head *this, *next;
592 int mm_users;
594 if (!(mm = get_task_mm(child)))
595 return child;
597 /* -1 because of our get_task_mm(): */
598 mm_users = atomic_read(&mm->mm_users) - 1;
599 if (mm_users <= 1)
600 goto out; /* not multi-threaded */
603 * Traverse the current process' children list. Every task that
604 * one attaches to becomes a child. And it is only attached children
605 * of the debugger that are of interest (ptrace_check_attach checks
606 * for this).
608 list_for_each_safe(this, next, &current->children) {
609 p = list_entry(this, struct task_struct, sibling);
610 if (p->tgid != child->tgid)
611 continue;
612 if (thread_matches(p, addr)) {
613 child = p;
614 goto out;
618 out:
619 mmput(mm);
620 return child;
624 * Write f32-f127 back to task->thread.fph if it has been modified.
626 inline void
627 ia64_flush_fph (struct task_struct *task)
629 struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
632 * Prevent migrating this task while
633 * we're fiddling with the FPU state
635 preempt_disable();
636 if (ia64_is_local_fpu_owner(task) && psr->mfh) {
637 psr->mfh = 0;
638 task->thread.flags |= IA64_THREAD_FPH_VALID;
639 ia64_save_fpu(&task->thread.fph[0]);
641 preempt_enable();
645 * Sync the fph state of the task so that it can be manipulated
646 * through thread.fph. If necessary, f32-f127 are written back to
647 * thread.fph or, if the fph state hasn't been used before, thread.fph
648 * is cleared to zeroes. Also, access to f32-f127 is disabled to
649 * ensure that the task picks up the state from thread.fph when it
650 * executes again.
652 void
653 ia64_sync_fph (struct task_struct *task)
655 struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
657 ia64_flush_fph(task);
658 if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
659 task->thread.flags |= IA64_THREAD_FPH_VALID;
660 memset(&task->thread.fph, 0, sizeof(task->thread.fph));
662 ia64_drop_fpu(task);
663 psr->dfh = 1;
666 static int
667 access_fr (struct unw_frame_info *info, int regnum, int hi,
668 unsigned long *data, int write_access)
670 struct ia64_fpreg fpval;
671 int ret;
673 ret = unw_get_fr(info, regnum, &fpval);
674 if (ret < 0)
675 return ret;
677 if (write_access) {
678 fpval.u.bits[hi] = *data;
679 ret = unw_set_fr(info, regnum, fpval);
680 } else
681 *data = fpval.u.bits[hi];
682 return ret;
686 * Change the machine-state of CHILD such that it will return via the normal
687 * kernel exit-path, rather than the syscall-exit path.
689 static void
690 convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt,
691 unsigned long cfm)
693 struct unw_frame_info info, prev_info;
694 unsigned long ip, sp, pr;
696 unw_init_from_blocked_task(&info, child);
697 while (1) {
698 prev_info = info;
699 if (unw_unwind(&info) < 0)
700 return;
702 unw_get_sp(&info, &sp);
703 if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
704 < IA64_PT_REGS_SIZE) {
705 dprintk("ptrace.%s: ran off the top of the kernel "
706 "stack\n", __FUNCTION__);
707 return;
709 if (unw_get_pr (&prev_info, &pr) < 0) {
710 unw_get_rp(&prev_info, &ip);
711 dprintk("ptrace.%s: failed to read "
712 "predicate register (ip=0x%lx)\n",
713 __FUNCTION__, ip);
714 return;
716 if (unw_is_intr_frame(&info)
717 && (pr & (1UL << PRED_USER_STACK)))
718 break;
722 * Note: at the time of this call, the target task is blocked
723 * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
724 * (aka, "pLvSys") we redirect execution from
725 * .work_pending_syscall_end to .work_processed_kernel.
727 unw_get_pr(&prev_info, &pr);
728 pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
729 pr |= (1UL << PRED_NON_SYSCALL);
730 unw_set_pr(&prev_info, pr);
732 pt->cr_ifs = (1UL << 63) | cfm;
734 * Clear the memory that is NOT written on syscall-entry to
735 * ensure we do not leak kernel-state to user when execution
736 * resumes.
738 pt->r2 = 0;
739 pt->r3 = 0;
740 pt->r14 = 0;
741 memset(&pt->r16, 0, 16*8); /* clear r16-r31 */
742 memset(&pt->f6, 0, 6*16); /* clear f6-f11 */
743 pt->b7 = 0;
744 pt->ar_ccv = 0;
745 pt->ar_csd = 0;
746 pt->ar_ssd = 0;
749 static int
750 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
751 struct unw_frame_info *info,
752 unsigned long *data, int write_access)
754 unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
755 char nat = 0;
757 if (write_access) {
758 nat_bits = *data;
759 scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
760 if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
761 dprintk("ptrace: failed to set ar.unat\n");
762 return -1;
764 for (regnum = 4; regnum <= 7; ++regnum) {
765 unw_get_gr(info, regnum, &dummy, &nat);
766 unw_set_gr(info, regnum, dummy,
767 (nat_bits >> regnum) & 1);
769 } else {
770 if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
771 dprintk("ptrace: failed to read ar.unat\n");
772 return -1;
774 nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
775 for (regnum = 4; regnum <= 7; ++regnum) {
776 unw_get_gr(info, regnum, &dummy, &nat);
777 nat_bits |= (nat != 0) << regnum;
779 *data = nat_bits;
781 return 0;
784 static int
785 access_uarea (struct task_struct *child, unsigned long addr,
786 unsigned long *data, int write_access)
788 unsigned long *ptr, regnum, urbs_end, rnat_addr, cfm;
789 struct switch_stack *sw;
790 struct pt_regs *pt;
791 # define pt_reg_addr(pt, reg) ((void *) \
792 ((unsigned long) (pt) \
793 + offsetof(struct pt_regs, reg)))
796 pt = task_pt_regs(child);
797 sw = (struct switch_stack *) (child->thread.ksp + 16);
799 if ((addr & 0x7) != 0) {
800 dprintk("ptrace: unaligned register address 0x%lx\n", addr);
801 return -1;
804 if (addr < PT_F127 + 16) {
805 /* accessing fph */
806 if (write_access)
807 ia64_sync_fph(child);
808 else
809 ia64_flush_fph(child);
810 ptr = (unsigned long *)
811 ((unsigned long) &child->thread.fph + addr);
812 } else if ((addr >= PT_F10) && (addr < PT_F11 + 16)) {
813 /* scratch registers untouched by kernel (saved in pt_regs) */
814 ptr = pt_reg_addr(pt, f10) + (addr - PT_F10);
815 } else if (addr >= PT_F12 && addr < PT_F15 + 16) {
817 * Scratch registers untouched by kernel (saved in
818 * switch_stack).
820 ptr = (unsigned long *) ((long) sw
821 + (addr - PT_NAT_BITS - 32));
822 } else if (addr < PT_AR_LC + 8) {
823 /* preserved state: */
824 struct unw_frame_info info;
825 char nat = 0;
826 int ret;
828 unw_init_from_blocked_task(&info, child);
829 if (unw_unwind_to_user(&info) < 0)
830 return -1;
832 switch (addr) {
833 case PT_NAT_BITS:
834 return access_nat_bits(child, pt, &info,
835 data, write_access);
837 case PT_R4: case PT_R5: case PT_R6: case PT_R7:
838 if (write_access) {
839 /* read NaT bit first: */
840 unsigned long dummy;
842 ret = unw_get_gr(&info, (addr - PT_R4)/8 + 4,
843 &dummy, &nat);
844 if (ret < 0)
845 return ret;
847 return unw_access_gr(&info, (addr - PT_R4)/8 + 4, data,
848 &nat, write_access);
850 case PT_B1: case PT_B2: case PT_B3:
851 case PT_B4: case PT_B5:
852 return unw_access_br(&info, (addr - PT_B1)/8 + 1, data,
853 write_access);
855 case PT_AR_EC:
856 return unw_access_ar(&info, UNW_AR_EC, data,
857 write_access);
859 case PT_AR_LC:
860 return unw_access_ar(&info, UNW_AR_LC, data,
861 write_access);
863 default:
864 if (addr >= PT_F2 && addr < PT_F5 + 16)
865 return access_fr(&info, (addr - PT_F2)/16 + 2,
866 (addr & 8) != 0, data,
867 write_access);
868 else if (addr >= PT_F16 && addr < PT_F31 + 16)
869 return access_fr(&info,
870 (addr - PT_F16)/16 + 16,
871 (addr & 8) != 0,
872 data, write_access);
873 else {
874 dprintk("ptrace: rejecting access to register "
875 "address 0x%lx\n", addr);
876 return -1;
879 } else if (addr < PT_F9+16) {
880 /* scratch state */
881 switch (addr) {
882 case PT_AR_BSP:
884 * By convention, we use PT_AR_BSP to refer to
885 * the end of the user-level backing store.
886 * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
887 * to get the real value of ar.bsp at the time
888 * the kernel was entered.
890 * Furthermore, when changing the contents of
891 * PT_AR_BSP (or PT_CFM) we MUST copy any
892 * users-level stacked registers that are
893 * stored on the kernel stack back to
894 * user-space because otherwise, we might end
895 * up clobbering kernel stacked registers.
896 * Also, if this happens while the task is
897 * blocked in a system call, which convert the
898 * state such that the non-system-call exit
899 * path is used. This ensures that the proper
900 * state will be picked up when resuming
901 * execution. However, it *also* means that
902 * once we write PT_AR_BSP/PT_CFM, it won't be
903 * possible to modify the syscall arguments of
904 * the pending system call any longer. This
905 * shouldn't be an issue because modifying
906 * PT_AR_BSP/PT_CFM generally implies that
907 * we're either abandoning the pending system
908 * call or that we defer it's re-execution
909 * (e.g., due to GDB doing an inferior
910 * function call).
912 urbs_end = ia64_get_user_rbs_end(child, pt, &cfm);
913 if (write_access) {
914 if (*data != urbs_end) {
915 if (ia64_sync_user_rbs(child, sw,
916 pt->ar_bspstore,
917 urbs_end) < 0)
918 return -1;
919 if (in_syscall(pt))
920 convert_to_non_syscall(child,
922 cfm);
924 * Simulate user-level write
925 * of ar.bsp:
927 pt->loadrs = 0;
928 pt->ar_bspstore = *data;
930 } else
931 *data = urbs_end;
932 return 0;
934 case PT_CFM:
935 urbs_end = ia64_get_user_rbs_end(child, pt, &cfm);
936 if (write_access) {
937 if (((cfm ^ *data) & PFM_MASK) != 0) {
938 if (ia64_sync_user_rbs(child, sw,
939 pt->ar_bspstore,
940 urbs_end) < 0)
941 return -1;
942 if (in_syscall(pt))
943 convert_to_non_syscall(child,
945 cfm);
946 pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
947 | (*data & PFM_MASK));
949 } else
950 *data = cfm;
951 return 0;
953 case PT_CR_IPSR:
954 if (write_access)
955 pt->cr_ipsr = ((*data & IPSR_MASK)
956 | (pt->cr_ipsr & ~IPSR_MASK));
957 else
958 *data = (pt->cr_ipsr & IPSR_MASK);
959 return 0;
961 case PT_AR_RSC:
962 if (write_access)
963 pt->ar_rsc = *data | (3 << 2); /* force PL3 */
964 else
965 *data = pt->ar_rsc;
966 return 0;
968 case PT_AR_RNAT:
969 urbs_end = ia64_get_user_rbs_end(child, pt, NULL);
970 rnat_addr = (long) ia64_rse_rnat_addr((long *)
971 urbs_end);
972 if (write_access)
973 return ia64_poke(child, sw, urbs_end,
974 rnat_addr, *data);
975 else
976 return ia64_peek(child, sw, urbs_end,
977 rnat_addr, data);
979 case PT_R1:
980 ptr = pt_reg_addr(pt, r1);
981 break;
982 case PT_R2: case PT_R3:
983 ptr = pt_reg_addr(pt, r2) + (addr - PT_R2);
984 break;
985 case PT_R8: case PT_R9: case PT_R10: case PT_R11:
986 ptr = pt_reg_addr(pt, r8) + (addr - PT_R8);
987 break;
988 case PT_R12: case PT_R13:
989 ptr = pt_reg_addr(pt, r12) + (addr - PT_R12);
990 break;
991 case PT_R14:
992 ptr = pt_reg_addr(pt, r14);
993 break;
994 case PT_R15:
995 ptr = pt_reg_addr(pt, r15);
996 break;
997 case PT_R16: case PT_R17: case PT_R18: case PT_R19:
998 case PT_R20: case PT_R21: case PT_R22: case PT_R23:
999 case PT_R24: case PT_R25: case PT_R26: case PT_R27:
1000 case PT_R28: case PT_R29: case PT_R30: case PT_R31:
1001 ptr = pt_reg_addr(pt, r16) + (addr - PT_R16);
1002 break;
1003 case PT_B0:
1004 ptr = pt_reg_addr(pt, b0);
1005 break;
1006 case PT_B6:
1007 ptr = pt_reg_addr(pt, b6);
1008 break;
1009 case PT_B7:
1010 ptr = pt_reg_addr(pt, b7);
1011 break;
1012 case PT_F6: case PT_F6+8: case PT_F7: case PT_F7+8:
1013 case PT_F8: case PT_F8+8: case PT_F9: case PT_F9+8:
1014 ptr = pt_reg_addr(pt, f6) + (addr - PT_F6);
1015 break;
1016 case PT_AR_BSPSTORE:
1017 ptr = pt_reg_addr(pt, ar_bspstore);
1018 break;
1019 case PT_AR_UNAT:
1020 ptr = pt_reg_addr(pt, ar_unat);
1021 break;
1022 case PT_AR_PFS:
1023 ptr = pt_reg_addr(pt, ar_pfs);
1024 break;
1025 case PT_AR_CCV:
1026 ptr = pt_reg_addr(pt, ar_ccv);
1027 break;
1028 case PT_AR_FPSR:
1029 ptr = pt_reg_addr(pt, ar_fpsr);
1030 break;
1031 case PT_CR_IIP:
1032 ptr = pt_reg_addr(pt, cr_iip);
1033 break;
1034 case PT_PR:
1035 ptr = pt_reg_addr(pt, pr);
1036 break;
1037 /* scratch register */
1039 default:
1040 /* disallow accessing anything else... */
1041 dprintk("ptrace: rejecting access to register "
1042 "address 0x%lx\n", addr);
1043 return -1;
1045 } else if (addr <= PT_AR_SSD) {
1046 ptr = pt_reg_addr(pt, ar_csd) + (addr - PT_AR_CSD);
1047 } else {
1048 /* access debug registers */
1050 if (addr >= PT_IBR) {
1051 regnum = (addr - PT_IBR) >> 3;
1052 ptr = &child->thread.ibr[0];
1053 } else {
1054 regnum = (addr - PT_DBR) >> 3;
1055 ptr = &child->thread.dbr[0];
1058 if (regnum >= 8) {
1059 dprintk("ptrace: rejecting access to register "
1060 "address 0x%lx\n", addr);
1061 return -1;
1063 #ifdef CONFIG_PERFMON
1065 * Check if debug registers are used by perfmon. This
1066 * test must be done once we know that we can do the
1067 * operation, i.e. the arguments are all valid, but
1068 * before we start modifying the state.
1070 * Perfmon needs to keep a count of how many processes
1071 * are trying to modify the debug registers for system
1072 * wide monitoring sessions.
1074 * We also include read access here, because they may
1075 * cause the PMU-installed debug register state
1076 * (dbr[], ibr[]) to be reset. The two arrays are also
1077 * used by perfmon, but we do not use
1078 * IA64_THREAD_DBG_VALID. The registers are restored
1079 * by the PMU context switch code.
1081 if (pfm_use_debug_registers(child)) return -1;
1082 #endif
1084 if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
1085 child->thread.flags |= IA64_THREAD_DBG_VALID;
1086 memset(child->thread.dbr, 0,
1087 sizeof(child->thread.dbr));
1088 memset(child->thread.ibr, 0,
1089 sizeof(child->thread.ibr));
1092 ptr += regnum;
1094 if ((regnum & 1) && write_access) {
1095 /* don't let the user set kernel-level breakpoints: */
1096 *ptr = *data & ~(7UL << 56);
1097 return 0;
1100 if (write_access)
1101 *ptr = *data;
1102 else
1103 *data = *ptr;
1104 return 0;
1107 static long
1108 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
1110 unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
1111 struct unw_frame_info info;
1112 struct ia64_fpreg fpval;
1113 struct switch_stack *sw;
1114 struct pt_regs *pt;
1115 long ret, retval = 0;
1116 char nat = 0;
1117 int i;
1119 if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs)))
1120 return -EIO;
1122 pt = task_pt_regs(child);
1123 sw = (struct switch_stack *) (child->thread.ksp + 16);
1124 unw_init_from_blocked_task(&info, child);
1125 if (unw_unwind_to_user(&info) < 0) {
1126 return -EIO;
1129 if (((unsigned long) ppr & 0x7) != 0) {
1130 dprintk("ptrace:unaligned register address %p\n", ppr);
1131 return -EIO;
1134 if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
1135 || access_uarea(child, PT_AR_EC, &ec, 0) < 0
1136 || access_uarea(child, PT_AR_LC, &lc, 0) < 0
1137 || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
1138 || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
1139 || access_uarea(child, PT_CFM, &cfm, 0)
1140 || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
1141 return -EIO;
1143 /* control regs */
1145 retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
1146 retval |= __put_user(psr, &ppr->cr_ipsr);
1148 /* app regs */
1150 retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1151 retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
1152 retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1153 retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1154 retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1155 retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1157 retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
1158 retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
1159 retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1160 retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
1161 retval |= __put_user(cfm, &ppr->cfm);
1163 /* gr1-gr3 */
1165 retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
1166 retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
1168 /* gr4-gr7 */
1170 for (i = 4; i < 8; i++) {
1171 if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
1172 return -EIO;
1173 retval |= __put_user(val, &ppr->gr[i]);
1176 /* gr8-gr11 */
1178 retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
1180 /* gr12-gr15 */
1182 retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
1183 retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
1184 retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
1186 /* gr16-gr31 */
1188 retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
1190 /* b0 */
1192 retval |= __put_user(pt->b0, &ppr->br[0]);
1194 /* b1-b5 */
1196 for (i = 1; i < 6; i++) {
1197 if (unw_access_br(&info, i, &val, 0) < 0)
1198 return -EIO;
1199 __put_user(val, &ppr->br[i]);
1202 /* b6-b7 */
1204 retval |= __put_user(pt->b6, &ppr->br[6]);
1205 retval |= __put_user(pt->b7, &ppr->br[7]);
1207 /* fr2-fr5 */
1209 for (i = 2; i < 6; i++) {
1210 if (unw_get_fr(&info, i, &fpval) < 0)
1211 return -EIO;
1212 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
1215 /* fr6-fr11 */
1217 retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
1218 sizeof(struct ia64_fpreg) * 6);
1220 /* fp scratch regs(12-15) */
1222 retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
1223 sizeof(struct ia64_fpreg) * 4);
1225 /* fr16-fr31 */
1227 for (i = 16; i < 32; i++) {
1228 if (unw_get_fr(&info, i, &fpval) < 0)
1229 return -EIO;
1230 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
1233 /* fph */
1235 ia64_flush_fph(child);
1236 retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
1237 sizeof(ppr->fr[32]) * 96);
1239 /* preds */
1241 retval |= __put_user(pt->pr, &ppr->pr);
1243 /* nat bits */
1245 retval |= __put_user(nat_bits, &ppr->nat);
1247 ret = retval ? -EIO : 0;
1248 return ret;
1251 static long
1252 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
1254 unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
1255 struct unw_frame_info info;
1256 struct switch_stack *sw;
1257 struct ia64_fpreg fpval;
1258 struct pt_regs *pt;
1259 long ret, retval = 0;
1260 int i;
1262 memset(&fpval, 0, sizeof(fpval));
1264 if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs)))
1265 return -EIO;
1267 pt = task_pt_regs(child);
1268 sw = (struct switch_stack *) (child->thread.ksp + 16);
1269 unw_init_from_blocked_task(&info, child);
1270 if (unw_unwind_to_user(&info) < 0) {
1271 return -EIO;
1274 if (((unsigned long) ppr & 0x7) != 0) {
1275 dprintk("ptrace:unaligned register address %p\n", ppr);
1276 return -EIO;
1279 /* control regs */
1281 retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
1282 retval |= __get_user(psr, &ppr->cr_ipsr);
1284 /* app regs */
1286 retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1287 retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1288 retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1289 retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1290 retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1291 retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1293 retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1294 retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1295 retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1296 retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1297 retval |= __get_user(cfm, &ppr->cfm);
1299 /* gr1-gr3 */
1301 retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1302 retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1304 /* gr4-gr7 */
1306 for (i = 4; i < 8; i++) {
1307 retval |= __get_user(val, &ppr->gr[i]);
1308 /* NaT bit will be set via PT_NAT_BITS: */
1309 if (unw_set_gr(&info, i, val, 0) < 0)
1310 return -EIO;
1313 /* gr8-gr11 */
1315 retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1317 /* gr12-gr15 */
1319 retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1320 retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1321 retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1323 /* gr16-gr31 */
1325 retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1327 /* b0 */
1329 retval |= __get_user(pt->b0, &ppr->br[0]);
1331 /* b1-b5 */
1333 for (i = 1; i < 6; i++) {
1334 retval |= __get_user(val, &ppr->br[i]);
1335 unw_set_br(&info, i, val);
1338 /* b6-b7 */
1340 retval |= __get_user(pt->b6, &ppr->br[6]);
1341 retval |= __get_user(pt->b7, &ppr->br[7]);
1343 /* fr2-fr5 */
1345 for (i = 2; i < 6; i++) {
1346 retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1347 if (unw_set_fr(&info, i, fpval) < 0)
1348 return -EIO;
1351 /* fr6-fr11 */
1353 retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1354 sizeof(ppr->fr[6]) * 6);
1356 /* fp scratch regs(12-15) */
1358 retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1359 sizeof(ppr->fr[12]) * 4);
1361 /* fr16-fr31 */
1363 for (i = 16; i < 32; i++) {
1364 retval |= __copy_from_user(&fpval, &ppr->fr[i],
1365 sizeof(fpval));
1366 if (unw_set_fr(&info, i, fpval) < 0)
1367 return -EIO;
1370 /* fph */
1372 ia64_sync_fph(child);
1373 retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1374 sizeof(ppr->fr[32]) * 96);
1376 /* preds */
1378 retval |= __get_user(pt->pr, &ppr->pr);
1380 /* nat bits */
1382 retval |= __get_user(nat_bits, &ppr->nat);
1384 retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1385 retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1386 retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1387 retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1388 retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1389 retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1390 retval |= access_uarea(child, PT_CFM, &cfm, 1);
1391 retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1393 ret = retval ? -EIO : 0;
1394 return ret;
1398 * Called by kernel/ptrace.c when detaching..
1400 * Make sure the single step bit is not set.
1402 void
1403 ptrace_disable (struct task_struct *child)
1405 struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1407 /* make sure the single step/taken-branch trap bits are not set: */
1408 clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1409 child_psr->ss = 0;
1410 child_psr->tb = 0;
1413 asmlinkage long
1414 sys_ptrace (long request, pid_t pid, unsigned long addr, unsigned long data)
1416 struct pt_regs *pt;
1417 unsigned long urbs_end, peek_or_poke;
1418 struct task_struct *child;
1419 struct switch_stack *sw;
1420 long ret;
1422 lock_kernel();
1423 ret = -EPERM;
1424 if (request == PTRACE_TRACEME) {
1425 ret = ptrace_traceme();
1426 goto out;
1429 peek_or_poke = (request == PTRACE_PEEKTEXT
1430 || request == PTRACE_PEEKDATA
1431 || request == PTRACE_POKETEXT
1432 || request == PTRACE_POKEDATA);
1433 ret = -ESRCH;
1434 read_lock(&tasklist_lock);
1436 child = find_task_by_pid(pid);
1437 if (child) {
1438 if (peek_or_poke)
1439 child = find_thread_for_addr(child, addr);
1440 get_task_struct(child);
1443 read_unlock(&tasklist_lock);
1444 if (!child)
1445 goto out;
1446 ret = -EPERM;
1447 if (pid == 1) /* no messing around with init! */
1448 goto out_tsk;
1450 if (request == PTRACE_ATTACH) {
1451 ret = ptrace_attach(child);
1452 goto out_tsk;
1455 ret = ptrace_check_attach(child, request == PTRACE_KILL);
1456 if (ret < 0)
1457 goto out_tsk;
1459 pt = task_pt_regs(child);
1460 sw = (struct switch_stack *) (child->thread.ksp + 16);
1462 switch (request) {
1463 case PTRACE_PEEKTEXT:
1464 case PTRACE_PEEKDATA:
1465 /* read word at location addr */
1466 urbs_end = ia64_get_user_rbs_end(child, pt, NULL);
1467 ret = ia64_peek(child, sw, urbs_end, addr, &data);
1468 if (ret == 0) {
1469 ret = data;
1470 /* ensure "ret" is not mistaken as an error code: */
1471 force_successful_syscall_return();
1473 goto out_tsk;
1475 case PTRACE_POKETEXT:
1476 case PTRACE_POKEDATA:
1477 /* write the word at location addr */
1478 urbs_end = ia64_get_user_rbs_end(child, pt, NULL);
1479 ret = ia64_poke(child, sw, urbs_end, addr, data);
1480 goto out_tsk;
1482 case PTRACE_PEEKUSR:
1483 /* read the word at addr in the USER area */
1484 if (access_uarea(child, addr, &data, 0) < 0) {
1485 ret = -EIO;
1486 goto out_tsk;
1488 ret = data;
1489 /* ensure "ret" is not mistaken as an error code */
1490 force_successful_syscall_return();
1491 goto out_tsk;
1493 case PTRACE_POKEUSR:
1494 /* write the word at addr in the USER area */
1495 if (access_uarea(child, addr, &data, 1) < 0) {
1496 ret = -EIO;
1497 goto out_tsk;
1499 ret = 0;
1500 goto out_tsk;
1502 case PTRACE_OLD_GETSIGINFO:
1503 /* for backwards-compatibility */
1504 ret = ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1505 goto out_tsk;
1507 case PTRACE_OLD_SETSIGINFO:
1508 /* for backwards-compatibility */
1509 ret = ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1510 goto out_tsk;
1512 case PTRACE_SYSCALL:
1513 /* continue and stop at next (return from) syscall */
1514 case PTRACE_CONT:
1515 /* restart after signal. */
1516 ret = -EIO;
1517 if (!valid_signal(data))
1518 goto out_tsk;
1519 if (request == PTRACE_SYSCALL)
1520 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
1521 else
1522 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
1523 child->exit_code = data;
1526 * Make sure the single step/taken-branch trap bits
1527 * are not set:
1529 clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1530 ia64_psr(pt)->ss = 0;
1531 ia64_psr(pt)->tb = 0;
1533 wake_up_process(child);
1534 ret = 0;
1535 goto out_tsk;
1537 case PTRACE_KILL:
1539 * Make the child exit. Best I can do is send it a
1540 * sigkill. Perhaps it should be put in the status
1541 * that it wants to exit.
1543 if (child->exit_state == EXIT_ZOMBIE)
1544 /* already dead */
1545 goto out_tsk;
1546 child->exit_code = SIGKILL;
1548 ptrace_disable(child);
1549 wake_up_process(child);
1550 ret = 0;
1551 goto out_tsk;
1553 case PTRACE_SINGLESTEP:
1554 /* let child execute for one instruction */
1555 case PTRACE_SINGLEBLOCK:
1556 ret = -EIO;
1557 if (!valid_signal(data))
1558 goto out_tsk;
1560 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
1561 set_tsk_thread_flag(child, TIF_SINGLESTEP);
1562 if (request == PTRACE_SINGLESTEP) {
1563 ia64_psr(pt)->ss = 1;
1564 } else {
1565 ia64_psr(pt)->tb = 1;
1567 child->exit_code = data;
1569 /* give it a chance to run. */
1570 wake_up_process(child);
1571 ret = 0;
1572 goto out_tsk;
1574 case PTRACE_DETACH:
1575 /* detach a process that was attached. */
1576 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
1577 ret = ptrace_detach(child, data);
1578 goto out_tsk;
1580 case PTRACE_GETREGS:
1581 ret = ptrace_getregs(child,
1582 (struct pt_all_user_regs __user *) data);
1583 goto out_tsk;
1585 case PTRACE_SETREGS:
1586 ret = ptrace_setregs(child,
1587 (struct pt_all_user_regs __user *) data);
1588 goto out_tsk;
1590 default:
1591 ret = ptrace_request(child, request, addr, data);
1592 goto out_tsk;
1594 out_tsk:
1595 put_task_struct(child);
1596 out:
1597 unlock_kernel();
1598 return ret;
1602 static void
1603 syscall_trace (void)
1606 * The 0x80 provides a way for the tracing parent to
1607 * distinguish between a syscall stop and SIGTRAP delivery.
1609 ptrace_notify(SIGTRAP
1610 | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));
1613 * This isn't the same as continuing with a signal, but it
1614 * will do for normal use. strace only continues with a
1615 * signal if the stopping signal is not SIGTRAP. -brl
1617 if (current->exit_code) {
1618 send_sig(current->exit_code, current, 1);
1619 current->exit_code = 0;
1623 /* "asmlinkage" so the input arguments are preserved... */
1625 asmlinkage void
1626 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1627 long arg4, long arg5, long arg6, long arg7,
1628 struct pt_regs regs)
1630 if (test_thread_flag(TIF_SYSCALL_TRACE)
1631 && (current->ptrace & PT_PTRACED))
1632 syscall_trace();
1634 if (unlikely(current->audit_context)) {
1635 long syscall;
1636 int arch;
1638 if (IS_IA32_PROCESS(&regs)) {
1639 syscall = regs.r1;
1640 arch = AUDIT_ARCH_I386;
1641 } else {
1642 syscall = regs.r15;
1643 arch = AUDIT_ARCH_IA64;
1646 audit_syscall_entry(arch, syscall, arg0, arg1, arg2, arg3);
1651 /* "asmlinkage" so the input arguments are preserved... */
1653 asmlinkage void
1654 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1655 long arg4, long arg5, long arg6, long arg7,
1656 struct pt_regs regs)
1658 if (unlikely(current->audit_context)) {
1659 int success = AUDITSC_RESULT(regs.r10);
1660 long result = regs.r8;
1662 if (success != AUDITSC_SUCCESS)
1663 result = -result;
1664 audit_syscall_exit(success, result);
1667 if ((test_thread_flag(TIF_SYSCALL_TRACE)
1668 || test_thread_flag(TIF_SINGLESTEP))
1669 && (current->ptrace & PT_PTRACED))
1670 syscall_trace();