arch/ia64/kernel/ptrace.c

   1 /*
   2  * Kernel support for the ptrace() and syscall tracing interfaces.
   3  *
   4  * Copyright (C) 1999-2005 Hewlett-Packard Co
   5  *      David Mosberger-Tang <davidm@hpl.hp.com>
   6  * Copyright (C) 2006 Intel Co
   7  *  2006-08-12  - IA64 Native Utrace implementation support added by
   8  *      Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
   9  *
  10  * Derived from the x86 and Alpha versions.
  11  */
  12 #include <linux/kernel.h>
  13 #include <linux/sched.h>
  14 #include <linux/mm.h>
  15 #include <linux/errno.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/user.h>
  18 #include <linux/security.h>
  19 #include <linux/audit.h>
  20 #include <linux/signal.h>
  21 #include <linux/regset.h>
  22 #include <linux/elf.h>
  23 #include <linux/tracehook.h>
  24
  25 #include <asm/pgtable.h>
  26 #include <asm/processor.h>
  27 #include <asm/ptrace_offsets.h>
  28 #include <asm/rse.h>
  29 #include <asm/uaccess.h>
  30 #include <asm/unwind.h>
  31 #ifdef CONFIG_PERFMON
  32 #include <asm/perfmon.h>
  33 #endif
  34
  35 #include "entry.h"
  36
  37 /*
  38  * Bits in the PSR that we allow ptrace() to change:
  39  *      be, up, ac, mfl, mfh (the user mask; five bits total)
  40  *      db (debug breakpoint fault; one bit)
  41  *      id (instruction debug fault disable; one bit)
  42  *      dd (data debug fault disable; one bit)
  43  *      ri (restart instruction; two bits)
  44  *      is (instruction set; one bit)
  45  */
  46 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS      \
  47                    | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
  48
  49 #define MASK(nbits)     ((1UL << (nbits)) - 1)  /* mask with NBITS bits set */
  50 #define PFM_MASK        MASK(38)
  51
  52 #define PTRACE_DEBUG    0
  53
  54 #if PTRACE_DEBUG
  55 # define dprintk(format...)     printk(format)
  56 # define inline
  57 #else
  58 # define dprintk(format...)
  59 #endif
  60
  61 /* Return TRUE if PT was created due to kernel-entry via a system-call.  */
  62
  63 static inline int
  64 in_syscall (struct pt_regs *pt)
  65 {
  66         return (long) pt->cr_ifs >= 0;
  67 }
  68
  69 /*
  70  * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
  71  * bitset where bit i is set iff the NaT bit of register i is set.
  72  */
  73 unsigned long
  74 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
  75 {
  76 #       define GET_BITS(first, last, unat)                              \
  77         ({                                                              \
  78                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
  79                 unsigned long nbits = (last - first + 1);               \
  80                 unsigned long mask = MASK(nbits) << first;              \
  81                 unsigned long dist;                                     \
  82                 if (bit < first)                                        \
  83                         dist = 64 + bit - first;                        \
  84                 else                                                    \
  85                         dist = bit - first;                             \
  86                 ia64_rotr(unat, dist) & mask;                           \
  87         })
  88         unsigned long val;
  89
  90         /*
  91          * Registers that are stored consecutively in struct pt_regs
  92          * can be handled in parallel.  If the register order in
  93          * struct_pt_regs changes, this code MUST be updated.
  94          */
  95         val  = GET_BITS( 1,  1, scratch_unat);
  96         val |= GET_BITS( 2,  3, scratch_unat);
  97         val |= GET_BITS(12, 13, scratch_unat);
  98         val |= GET_BITS(14, 14, scratch_unat);
  99         val |= GET_BITS(15, 15, scratch_unat);
 100         val |= GET_BITS( 8, 11, scratch_unat);
 101         val |= GET_BITS(16, 31, scratch_unat);
 102         return val;
 103
 104 #       undef GET_BITS
 105 }
 106
 107 /*
 108  * Set the NaT bits for the scratch registers according to NAT and
 109  * return the resulting unat (assuming the scratch registers are
 110  * stored in PT).
 111  */
 112 unsigned long
 113 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
 114 {
 115 #       define PUT_BITS(first, last, nat)                               \
 116         ({                                                              \
 117                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
 118                 unsigned long nbits = (last - first + 1);               \
 119                 unsigned long mask = MASK(nbits) << first;              \
 120                 long dist;                                              \
 121                 if (bit < first)                                        \
 122                         dist = 64 + bit - first;                        \
 123                 else                                                    \
 124                         dist = bit - first;                             \
 125                 ia64_rotl(nat & mask, dist);                            \
 126         })
 127         unsigned long scratch_unat;
 128
 129         /*
 130          * Registers that are stored consecutively in struct pt_regs
 131          * can be handled in parallel.  If the register order in
 132          * struct_pt_regs changes, this code MUST be updated.
 133          */
 134         scratch_unat  = PUT_BITS( 1,  1, nat);
 135         scratch_unat |= PUT_BITS( 2,  3, nat);
 136         scratch_unat |= PUT_BITS(12, 13, nat);
 137         scratch_unat |= PUT_BITS(14, 14, nat);
 138         scratch_unat |= PUT_BITS(15, 15, nat);
 139         scratch_unat |= PUT_BITS( 8, 11, nat);
 140         scratch_unat |= PUT_BITS(16, 31, nat);
 141
 142         return scratch_unat;
 143
 144 #       undef PUT_BITS
 145 }
 146
 147 #define IA64_MLX_TEMPLATE       0x2
 148 #define IA64_MOVL_OPCODE        6
 149
 150 void
 151 ia64_increment_ip (struct pt_regs *regs)
 152 {
 153         unsigned long w0, ri = ia64_psr(regs)->ri + 1;
 154
 155         if (ri > 2) {
 156                 ri = 0;
 157                 regs->cr_iip += 16;
 158         } else if (ri == 2) {
 159                 get_user(w0, (char __user *) regs->cr_iip + 0);
 160                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
 161                         /*
 162                          * rfi'ing to slot 2 of an MLX bundle causes
 163                          * an illegal operation fault.  We don't want
 164                          * that to happen...
 165                          */
 166                         ri = 0;
 167                         regs->cr_iip += 16;
 168                 }
 169         }
 170         ia64_psr(regs)->ri = ri;
 171 }
 172
 173 void
 174 ia64_decrement_ip (struct pt_regs *regs)
 175 {
 176         unsigned long w0, ri = ia64_psr(regs)->ri - 1;
 177
 178         if (ia64_psr(regs)->ri == 0) {
 179                 regs->cr_iip -= 16;
 180                 ri = 2;
 181                 get_user(w0, (char __user *) regs->cr_iip + 0);
 182                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
 183                         /*
 184                          * rfi'ing to slot 2 of an MLX bundle causes
 185                          * an illegal operation fault.  We don't want
 186                          * that to happen...
 187                          */
 188                         ri = 1;
 189                 }
 190         }
 191         ia64_psr(regs)->ri = ri;
 192 }
 193
 194 /*
 195  * This routine is used to read an rnat bits that are stored on the
 196  * kernel backing store.  Since, in general, the alignment of the user
 197  * and kernel are different, this is not completely trivial.  In
 198  * essence, we need to construct the user RNAT based on up to two
 199  * kernel RNAT values and/or the RNAT value saved in the child's
 200  * pt_regs.
 201  *
 202  * user rbs
 203  *
 204  * +--------+ <-- lowest address
 205  * | slot62 |
 206  * +--------+
 207  * |  rnat  | 0x....1f8
 208  * +--------+
 209  * | slot00 | \
 210  * +--------+ |
 211  * | slot01 | > child_regs->ar_rnat
 212  * +--------+ |
 213  * | slot02 | /                         kernel rbs
 214  * +--------+                           +--------+
 215  *          <- child_regs->ar_bspstore  | slot61 | <-- krbs
 216  * +- - - - +                           +--------+
 217  *                                      | slot62 |
 218  * +- - - - +                           +--------+
 219  *                                      |  rnat  |
 220  * +- - - - +                           +--------+
 221  *   vrnat                              | slot00 |
 222  * +- - - - +                           +--------+
 223  *                                      =        =
 224  *                                      +--------+
 225  *                                      | slot00 | \
 226  *                                      +--------+ |
 227  *                                      | slot01 | > child_stack->ar_rnat
 228  *                                      +--------+ |
 229  *                                      | slot02 | /
 230  *                                      +--------+
 231  *                                                <--- child_stack->ar_bspstore
 232  *
 233  * The way to think of this code is as follows: bit 0 in the user rnat
 234  * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
 235  * value.  The kernel rnat value holding this bit is stored in
 236  * variable rnat0.  rnat1 is loaded with the kernel rnat value that
 237  * form the upper bits of the user rnat value.
 238  *
 239  * Boundary cases:
 240  *
 241  * o when reading the rnat "below" the first rnat slot on the kernel
 242  *   backing store, rnat0/rnat1 are set to 0 and the low order bits are
 243  *   merged in from pt->ar_rnat.
 244  *
 245  * o when reading the rnat "above" the last rnat slot on the kernel
 246  *   backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
 247  */
 248 static unsigned long
 249 get_rnat (struct task_struct *task, struct switch_stack *sw,
 250           unsigned long *krbs, unsigned long *urnat_addr,
 251           unsigned long *urbs_end)
 252 {
 253         unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
 254         unsigned long umask = 0, mask, m;
 255         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
 256         long num_regs, nbits;
 257         struct pt_regs *pt;
 258
 259         pt = task_pt_regs(task);
 260         kbsp = (unsigned long *) sw->ar_bspstore;
 261         ubspstore = (unsigned long *) pt->ar_bspstore;
 262
 263         if (urbs_end < urnat_addr)
 264                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
 265         else
 266                 nbits = 63;
 267         mask = MASK(nbits);
 268         /*
 269          * First, figure out which bit number slot 0 in user-land maps
 270          * to in the kernel rnat.  Do this by figuring out how many
 271          * register slots we're beyond the user's backingstore and
 272          * then computing the equivalent address in kernel space.
 273          */
 274         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
 275         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
 276         shift = ia64_rse_slot_num(slot0_kaddr);
 277         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
 278         rnat0_kaddr = rnat1_kaddr - 64;
 279
 280         if (ubspstore + 63 > urnat_addr) {
 281                 /* some bits need to be merged in from pt->ar_rnat */
 282                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
 283                 urnat = (pt->ar_rnat & umask);
 284                 mask &= ~umask;
 285                 if (!mask)
 286                         return urnat;
 287         }
 288
 289         m = mask << shift;
 290         if (rnat0_kaddr >= kbsp)
 291                 rnat0 = sw->ar_rnat;
 292         else if (rnat0_kaddr > krbs)
 293                 rnat0 = *rnat0_kaddr;
 294         urnat |= (rnat0 & m) >> shift;
 295
 296         m = mask >> (63 - shift);
 297         if (rnat1_kaddr >= kbsp)
 298                 rnat1 = sw->ar_rnat;
 299         else if (rnat1_kaddr > krbs)
 300                 rnat1 = *rnat1_kaddr;
 301         urnat |= (rnat1 & m) << (63 - shift);
 302         return urnat;
 303 }
 304
 305 /*
 306  * The reverse of get_rnat.
 307  */
 308 static void
 309 put_rnat (struct task_struct *task, struct switch_stack *sw,
 310           unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
 311           unsigned long *urbs_end)
 312 {
 313         unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
 314         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
 315         long num_regs, nbits;
 316         struct pt_regs *pt;
 317         unsigned long cfm, *urbs_kargs;
 318
 319         pt = task_pt_regs(task);
 320         kbsp = (unsigned long *) sw->ar_bspstore;
 321         ubspstore = (unsigned long *) pt->ar_bspstore;
 322
 323         urbs_kargs = urbs_end;
 324         if (in_syscall(pt)) {
 325                 /*
 326                  * If entered via syscall, don't allow user to set rnat bits
 327                  * for syscall args.
 328                  */
 329                 cfm = pt->cr_ifs;
 330                 urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
 331         }
 332
 333         if (urbs_kargs >= urnat_addr)
 334                 nbits = 63;
 335         else {
 336                 if ((urnat_addr - 63) >= urbs_kargs)
 337                         return;
 338                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
 339         }
 340         mask = MASK(nbits);
 341
 342         /*
 343          * First, figure out which bit number slot 0 in user-land maps
 344          * to in the kernel rnat.  Do this by figuring out how many
 345          * register slots we're beyond the user's backingstore and
 346          * then computing the equivalent address in kernel space.
 347          */
 348         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
 349         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
 350         shift = ia64_rse_slot_num(slot0_kaddr);
 351         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
 352         rnat0_kaddr = rnat1_kaddr - 64;
 353
 354         if (ubspstore + 63 > urnat_addr) {
 355                 /* some bits need to be place in pt->ar_rnat: */
 356                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
 357                 pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
 358                 mask &= ~umask;
 359                 if (!mask)
 360                         return;
 361         }
 362         /*
 363          * Note: Section 11.1 of the EAS guarantees that bit 63 of an
 364          * rnat slot is ignored. so we don't have to clear it here.
 365          */
 366         rnat0 = (urnat << shift);
 367         m = mask << shift;
 368         if (rnat0_kaddr >= kbsp)
 369                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
 370         else if (rnat0_kaddr > krbs)
 371                 *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
 372
 373         rnat1 = (urnat >> (63 - shift));
 374         m = mask >> (63 - shift);
 375         if (rnat1_kaddr >= kbsp)
 376                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
 377         else if (rnat1_kaddr > krbs)
 378                 *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
 379 }
 380
 381 static inline int
 382 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
 383                unsigned long urbs_end)
 384 {
 385         unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
 386                                                       urbs_end);
 387         return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
 388 }
 389
 390 /*
 391  * Read a word from the user-level backing store of task CHILD.  ADDR
 392  * is the user-level address to read the word from, VAL a pointer to
 393  * the return value, and USER_BSP gives the end of the user-level
 394  * backing store (i.e., it's the address that would be in ar.bsp after
 395  * the user executed a "cover" instruction).
 396  *
 397  * This routine takes care of accessing the kernel register backing
 398  * store for those registers that got spilled there.  It also takes
 399  * care of calculating the appropriate RNaT collection words.
 400  */
 401 long
 402 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
 403            unsigned long user_rbs_end, unsigned long addr, long *val)
 404 {
 405         unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
 406         struct pt_regs *child_regs;
 407         size_t copied;
 408         long ret;
 409
 410         urbs_end = (long *) user_rbs_end;
 411         laddr = (unsigned long *) addr;
 412         child_regs = task_pt_regs(child);
 413         bspstore = (unsigned long *) child_regs->ar_bspstore;
 414         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 415         if (on_kernel_rbs(addr, (unsigned long) bspstore,
 416                           (unsigned long) urbs_end))
 417         {
 418                 /*
 419                  * Attempt to read the RBS in an area that's actually
 420                  * on the kernel RBS => read the corresponding bits in
 421                  * the kernel RBS.
 422                  */
 423                 rnat_addr = ia64_rse_rnat_addr(laddr);
 424                 ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
 425
 426                 if (laddr == rnat_addr) {
 427                         /* return NaT collection word itself */
 428                         *val = ret;
 429                         return 0;
 430                 }
 431
 432                 if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
 433                         /*
 434                          * It is implementation dependent whether the
 435                          * data portion of a NaT value gets saved on a
 436                          * st8.spill or RSE spill (e.g., see EAS 2.6,
 437                          * 4.4.4.6 Register Spill and Fill).  To get
 438                          * consistent behavior across all possible
 439                          * IA-64 implementations, we return zero in
 440                          * this case.
 441                          */
 442                         *val = 0;
 443                         return 0;
 444                 }
 445
 446                 if (laddr < urbs_end) {
 447                         /*
 448                          * The desired word is on the kernel RBS and
 449                          * is not a NaT.
 450                          */
 451                         regnum = ia64_rse_num_regs(bspstore, laddr);
 452                         *val = *ia64_rse_skip_regs(krbs, regnum);
 453                         return 0;
 454                 }
 455         }
 456         copied = access_process_vm(child, addr, &ret, sizeof(ret), 0);
 457         if (copied != sizeof(ret))
 458                 return -EIO;
 459         *val = ret;
 460         return 0;
 461 }
 462
 463 long
 464 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
 465            unsigned long user_rbs_end, unsigned long addr, long val)
 466 {
 467         unsigned long *bspstore, *krbs, regnum, *laddr;
 468         unsigned long *urbs_end = (long *) user_rbs_end;
 469         struct pt_regs *child_regs;
 470
 471         laddr = (unsigned long *) addr;
 472         child_regs = task_pt_regs(child);
 473         bspstore = (unsigned long *) child_regs->ar_bspstore;
 474         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 475         if (on_kernel_rbs(addr, (unsigned long) bspstore,
 476                           (unsigned long) urbs_end))
 477         {
 478                 /*
 479                  * Attempt to write the RBS in an area that's actually
 480                  * on the kernel RBS => write the corresponding bits
 481                  * in the kernel RBS.
 482                  */
 483                 if (ia64_rse_is_rnat_slot(laddr))
 484                         put_rnat(child, child_stack, krbs, laddr, val,
 485                                  urbs_end);
 486                 else {
 487                         if (laddr < urbs_end) {
 488                                 regnum = ia64_rse_num_regs(bspstore, laddr);
 489                                 *ia64_rse_skip_regs(krbs, regnum) = val;
 490                         }
 491                 }
 492         } else if (access_process_vm(child, addr, &val, sizeof(val), 1)
 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), 1)
 547                     != sizeof(val))
 548                         return -EIO;
 549         }
 550         return 0;
 551 }
 552
 553 static long
 554 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
 555                 unsigned long user_rbs_start, unsigned long user_rbs_end)
 556 {
 557         unsigned long addr, val;
 558         long ret;
 559
 560         /* now copy word for word from user rbs to kernel rbs: */
 561         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 562                 if (access_process_vm(child, addr, &val, sizeof(val), 0)
 563                                 != sizeof(val))
 564                         return -EIO;
 565
 566                 ret = ia64_poke(child, sw, user_rbs_end, addr, val);
 567                 if (ret < 0)
 568                         return ret;
 569         }
 570         return 0;
 571 }
 572
 573 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
 574                             unsigned long, unsigned long);
 575
 576 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
 577 {
 578         struct pt_regs *pt;
 579         unsigned long urbs_end;
 580         syncfunc_t fn = arg;
 581
 582         if (unw_unwind_to_user(info) < 0)
 583                 return;
 584         pt = task_pt_regs(info->task);
 585         urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
 586
 587         fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
 588 }
 589
 590 /*
 591  * when a thread is stopped (ptraced), debugger might change thread's user
 592  * stack (change memory directly), and we must avoid the RSE stored in kernel
 593  * to override user stack (user space's RSE is newer than kernel's in the
 594  * case). To workaround the issue, we copy kernel RSE to user RSE before the
 595  * task is stopped, so user RSE has updated data.  we then copy user RSE to
 596  * kernel after the task is resummed from traced stop and kernel will use the
 597  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
 598  * synchronize user RSE to kernel.
 599  */
 600 void ia64_ptrace_stop(void)
 601 {
 602         if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
 603                 return;
 604         set_notify_resume(current);
 605         unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
 606 }
 607
 608 /*
 609  * This is called to read back the register backing store.
 610  */
 611 void ia64_sync_krbs(void)
 612 {
 613         clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
 614
 615         unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
 616 }
 617
 618 /*
 619  * After PTRACE_ATTACH, a thread's register backing store area in user
 620  * space is assumed to contain correct data whenever the thread is
 621  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
 622  * But if the child was already stopped for job control when we attach
 623  * to it, then it might not ever get into ptrace_stop by the time we
 624  * want to examine the user memory containing the RBS.
 625  */
 626 void
 627 ptrace_attach_sync_user_rbs (struct task_struct *child)
 628 {
 629         int stopped = 0;
 630         struct unw_frame_info info;
 631
 632         /*
 633          * If the child is in TASK_STOPPED, we need to change that to
 634          * TASK_TRACED momentarily while we operate on it.  This ensures
 635          * that the child won't be woken up and return to user mode while
 636          * we are doing the sync.  (It can only be woken up for SIGKILL.)
 637          */
 638
 639         read_lock(&tasklist_lock);
 640         if (child->sighand) {
 641                 spin_lock_irq(&child->sighand->siglock);
 642                 if (child->state == TASK_STOPPED &&
 643                     !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
 644                         set_notify_resume(child);
 645
 646                         child->state = TASK_TRACED;
 647                         stopped = 1;
 648                 }
 649                 spin_unlock_irq(&child->sighand->siglock);
 650         }
 651         read_unlock(&tasklist_lock);
 652
 653         if (!stopped)
 654                 return;
 655
 656         unw_init_from_blocked_task(&info, child);
 657         do_sync_rbs(&info, ia64_sync_user_rbs);
 658
 659         /*
 660          * Now move the child back into TASK_STOPPED if it should be in a
 661          * job control stop, so that SIGCONT can be used to wake it up.
 662          */
 663         read_lock(&tasklist_lock);
 664         if (child->sighand) {
 665                 spin_lock_irq(&child->sighand->siglock);
 666                 if (child->state == TASK_TRACED &&
 667                     (child->signal->flags & SIGNAL_STOP_STOPPED)) {
 668                         child->state = TASK_STOPPED;
 669                 }
 670                 spin_unlock_irq(&child->sighand->siglock);
 671         }
 672         read_unlock(&tasklist_lock);
 673 }
 674
 675 /*
 676  * Write f32-f127 back to task->thread.fph if it has been modified.
 677  */
 678 inline void
 679 ia64_flush_fph (struct task_struct *task)
 680 {
 681         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 682
 683         /*
 684          * Prevent migrating this task while
 685          * we're fiddling with the FPU state
 686          */
 687         preempt_disable();
 688         if (ia64_is_local_fpu_owner(task) && psr->mfh) {
 689                 psr->mfh = 0;
 690                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 691                 ia64_save_fpu(&task->thread.fph[0]);
 692         }
 693         preempt_enable();
 694 }
 695
 696 /*
 697  * Sync the fph state of the task so that it can be manipulated
 698  * through thread.fph.  If necessary, f32-f127 are written back to
 699  * thread.fph or, if the fph state hasn't been used before, thread.fph
 700  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
 701  * ensure that the task picks up the state from thread.fph when it
 702  * executes again.
 703  */
 704 void
 705 ia64_sync_fph (struct task_struct *task)
 706 {
 707         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 708
 709         ia64_flush_fph(task);
 710         if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
 711                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 712                 memset(&task->thread.fph, 0, sizeof(task->thread.fph));
 713         }
 714         ia64_drop_fpu(task);
 715         psr->dfh = 1;
 716 }
 717
 718 /*
 719  * Change the machine-state of CHILD such that it will return via the normal
 720  * kernel exit-path, rather than the syscall-exit path.
 721  */
 722 static void
 723 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
 724                         unsigned long cfm)
 725 {
 726         struct unw_frame_info info, prev_info;
 727         unsigned long ip, sp, pr;
 728
 729         unw_init_from_blocked_task(&info, child);
 730         while (1) {
 731                 prev_info = info;
 732                 if (unw_unwind(&info) < 0)
 733                         return;
 734
 735                 unw_get_sp(&info, &sp);
 736                 if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
 737                     < IA64_PT_REGS_SIZE) {
 738                         dprintk("ptrace.%s: ran off the top of the kernel "
 739                                 "stack\n", __func__);
 740                         return;
 741                 }
 742                 if (unw_get_pr (&prev_info, &pr) < 0) {
 743                         unw_get_rp(&prev_info, &ip);
 744                         dprintk("ptrace.%s: failed to read "
 745                                 "predicate register (ip=0x%lx)\n",
 746                                 __func__, ip);
 747                         return;
 748                 }
 749                 if (unw_is_intr_frame(&info)
 750                     && (pr & (1UL << PRED_USER_STACK)))
 751                         break;
 752         }
 753
 754         /*
 755          * Note: at the time of this call, the target task is blocked
 756          * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
 757          * (aka, "pLvSys") we redirect execution from
 758          * .work_pending_syscall_end to .work_processed_kernel.
 759          */
 760         unw_get_pr(&prev_info, &pr);
 761         pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
 762         pr |=  (1UL << PRED_NON_SYSCALL);
 763         unw_set_pr(&prev_info, pr);
 764
 765         pt->cr_ifs = (1UL << 63) | cfm;
 766         /*
 767          * Clear the memory that is NOT written on syscall-entry to
 768          * ensure we do not leak kernel-state to user when execution
 769          * resumes.
 770          */
 771         pt->r2 = 0;
 772         pt->r3 = 0;
 773         pt->r14 = 0;
 774         memset(&pt->r16, 0, 16*8);      /* clear r16-r31 */
 775         memset(&pt->f6, 0, 6*16);       /* clear f6-f11 */
 776         pt->b7 = 0;
 777         pt->ar_ccv = 0;
 778         pt->ar_csd = 0;
 779         pt->ar_ssd = 0;
 780 }
 781
 782 static int
 783 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
 784                  struct unw_frame_info *info,
 785                  unsigned long *data, int write_access)
 786 {
 787         unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
 788         char nat = 0;
 789
 790         if (write_access) {
 791                 nat_bits = *data;
 792                 scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
 793                 if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
 794                         dprintk("ptrace: failed to set ar.unat\n");
 795                         return -1;
 796                 }
 797                 for (regnum = 4; regnum <= 7; ++regnum) {
 798                         unw_get_gr(info, regnum, &dummy, &nat);
 799                         unw_set_gr(info, regnum, dummy,
 800                                    (nat_bits >> regnum) & 1);
 801                 }
 802         } else {
 803                 if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
 804                         dprintk("ptrace: failed to read ar.unat\n");
 805                         return -1;
 806                 }
 807                 nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
 808                 for (regnum = 4; regnum <= 7; ++regnum) {
 809                         unw_get_gr(info, regnum, &dummy, &nat);
 810                         nat_bits |= (nat != 0) << regnum;
 811                 }
 812                 *data = nat_bits;
 813         }
 814         return 0;
 815 }
 816
 817 static int
 818 access_uarea (struct task_struct *child, unsigned long addr,
 819               unsigned long *data, int write_access);
 820
 821 static long
 822 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 823 {
 824         unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
 825         struct unw_frame_info info;
 826         struct ia64_fpreg fpval;
 827         struct switch_stack *sw;
 828         struct pt_regs *pt;
 829         long ret, retval = 0;
 830         char nat = 0;
 831         int i;
 832
 833         if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs)))
 834                 return -EIO;
 835
 836         pt = task_pt_regs(child);
 837         sw = (struct switch_stack *) (child->thread.ksp + 16);
 838         unw_init_from_blocked_task(&info, child);
 839         if (unw_unwind_to_user(&info) < 0) {
 840                 return -EIO;
 841         }
 842
 843         if (((unsigned long) ppr & 0x7) != 0) {
 844                 dprintk("ptrace:unaligned register address %p\n", ppr);
 845                 return -EIO;
 846         }
 847
 848         if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
 849             || access_uarea(child, PT_AR_EC, &ec, 0) < 0
 850             || access_uarea(child, PT_AR_LC, &lc, 0) < 0
 851             || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
 852             || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
 853             || access_uarea(child, PT_CFM, &cfm, 0)
 854             || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
 855                 return -EIO;
 856
 857         /* control regs */
 858
 859         retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
 860         retval |= __put_user(psr, &ppr->cr_ipsr);
 861
 862         /* app regs */
 863
 864         retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
 865         retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
 866         retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
 867         retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
 868         retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
 869         retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
 870
 871         retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
 872         retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
 873         retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
 874         retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
 875         retval |= __put_user(cfm, &ppr->cfm);
 876
 877         /* gr1-gr3 */
 878
 879         retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
 880         retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
 881
 882         /* gr4-gr7 */
 883
 884         for (i = 4; i < 8; i++) {
 885                 if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
 886                         return -EIO;
 887                 retval |= __put_user(val, &ppr->gr[i]);
 888         }
 889
 890         /* gr8-gr11 */
 891
 892         retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
 893
 894         /* gr12-gr15 */
 895
 896         retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
 897         retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
 898         retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
 899
 900         /* gr16-gr31 */
 901
 902         retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
 903
 904         /* b0 */
 905
 906         retval |= __put_user(pt->b0, &ppr->br[0]);
 907
 908         /* b1-b5 */
 909
 910         for (i = 1; i < 6; i++) {
 911                 if (unw_access_br(&info, i, &val, 0) < 0)
 912                         return -EIO;
 913                 __put_user(val, &ppr->br[i]);
 914         }
 915
 916         /* b6-b7 */
 917
 918         retval |= __put_user(pt->b6, &ppr->br[6]);
 919         retval |= __put_user(pt->b7, &ppr->br[7]);
 920
 921         /* fr2-fr5 */
 922
 923         for (i = 2; i < 6; i++) {
 924                 if (unw_get_fr(&info, i, &fpval) < 0)
 925                         return -EIO;
 926                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 927         }
 928
 929         /* fr6-fr11 */
 930
 931         retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
 932                                  sizeof(struct ia64_fpreg) * 6);
 933
 934         /* fp scratch regs(12-15) */
 935
 936         retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
 937                                  sizeof(struct ia64_fpreg) * 4);
 938
 939         /* fr16-fr31 */
 940
 941         for (i = 16; i < 32; i++) {
 942                 if (unw_get_fr(&info, i, &fpval) < 0)
 943                         return -EIO;
 944                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 945         }
 946
 947         /* fph */
 948
 949         ia64_flush_fph(child);
 950         retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
 951                                  sizeof(ppr->fr[32]) * 96);
 952
 953         /*  preds */
 954
 955         retval |= __put_user(pt->pr, &ppr->pr);
 956
 957         /* nat bits */
 958
 959         retval |= __put_user(nat_bits, &ppr->nat);
 960
 961         ret = retval ? -EIO : 0;
 962         return ret;
 963 }
 964
 965 static long
 966 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 967 {
 968         unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
 969         struct unw_frame_info info;
 970         struct switch_stack *sw;
 971         struct ia64_fpreg fpval;
 972         struct pt_regs *pt;
 973         long ret, retval = 0;
 974         int i;
 975
 976         memset(&fpval, 0, sizeof(fpval));
 977
 978         if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs)))
 979                 return -EIO;
 980
 981         pt = task_pt_regs(child);
 982         sw = (struct switch_stack *) (child->thread.ksp + 16);
 983         unw_init_from_blocked_task(&info, child);
 984         if (unw_unwind_to_user(&info) < 0) {
 985                 return -EIO;
 986         }
 987
 988         if (((unsigned long) ppr & 0x7) != 0) {
 989                 dprintk("ptrace:unaligned register address %p\n", ppr);
 990                 return -EIO;
 991         }
 992
 993         /* control regs */
 994
 995         retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
 996         retval |= __get_user(psr, &ppr->cr_ipsr);
 997
 998         /* app regs */
 999
1000         retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1001         retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1002         retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1003         retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1004         retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1005         retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1006
1007         retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1008         retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1009         retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1010         retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1011         retval |= __get_user(cfm, &ppr->cfm);
1012
1013         /* gr1-gr3 */
1014
1015         retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1016         retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1017
1018         /* gr4-gr7 */
1019
1020         for (i = 4; i < 8; i++) {
1021                 retval |= __get_user(val, &ppr->gr[i]);
1022                 /* NaT bit will be set via PT_NAT_BITS: */
1023                 if (unw_set_gr(&info, i, val, 0) < 0)
1024                         return -EIO;
1025         }
1026
1027         /* gr8-gr11 */
1028
1029         retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1030
1031         /* gr12-gr15 */
1032
1033         retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1034         retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1035         retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1036
1037         /* gr16-gr31 */
1038
1039         retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1040
1041         /* b0 */
1042
1043         retval |= __get_user(pt->b0, &ppr->br[0]);
1044
1045         /* b1-b5 */
1046
1047         for (i = 1; i < 6; i++) {
1048                 retval |= __get_user(val, &ppr->br[i]);
1049                 unw_set_br(&info, i, val);
1050         }
1051
1052         /* b6-b7 */
1053
1054         retval |= __get_user(pt->b6, &ppr->br[6]);
1055         retval |= __get_user(pt->b7, &ppr->br[7]);
1056
1057         /* fr2-fr5 */
1058
1059         for (i = 2; i < 6; i++) {
1060                 retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1061                 if (unw_set_fr(&info, i, fpval) < 0)
1062                         return -EIO;
1063         }
1064
1065         /* fr6-fr11 */
1066
1067         retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1068                                    sizeof(ppr->fr[6]) * 6);
1069
1070         /* fp scratch regs(12-15) */
1071
1072         retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1073                                    sizeof(ppr->fr[12]) * 4);
1074
1075         /* fr16-fr31 */
1076
1077         for (i = 16; i < 32; i++) {
1078                 retval |= __copy_from_user(&fpval, &ppr->fr[i],
1079                                            sizeof(fpval));
1080                 if (unw_set_fr(&info, i, fpval) < 0)
1081                         return -EIO;
1082         }
1083
1084         /* fph */
1085
1086         ia64_sync_fph(child);
1087         retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1088                                    sizeof(ppr->fr[32]) * 96);
1089
1090         /* preds */
1091
1092         retval |= __get_user(pt->pr, &ppr->pr);
1093
1094         /* nat bits */
1095
1096         retval |= __get_user(nat_bits, &ppr->nat);
1097
1098         retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1099         retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1100         retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1101         retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1102         retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1103         retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1104         retval |= access_uarea(child, PT_CFM, &cfm, 1);
1105         retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1106
1107         ret = retval ? -EIO : 0;
1108         return ret;
1109 }
1110
1111 void
1112 user_enable_single_step (struct task_struct *child)
1113 {
1114         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1115
1116         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1117         child_psr->ss = 1;
1118 }
1119
1120 void
1121 user_enable_block_step (struct task_struct *child)
1122 {
1123         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1124
1125         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1126         child_psr->tb = 1;
1127 }
1128
1129 void
1130 user_disable_single_step (struct task_struct *child)
1131 {
1132         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1133
1134         /* make sure the single step/taken-branch trap bits are not set: */
1135         clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1136         child_psr->ss = 0;
1137         child_psr->tb = 0;
1138 }
1139
1140 /*
1141  * Called by kernel/ptrace.c when detaching..
1142  *
1143  * Make sure the single step bit is not set.
1144  */
1145 void
1146 ptrace_disable (struct task_struct *child)
1147 {
1148         user_disable_single_step(child);
1149 }
1150
1151 long
1152 arch_ptrace (struct task_struct *child, long request,
1153              unsigned long addr, unsigned long data)
1154 {
1155         switch (request) {
1156         case PTRACE_PEEKTEXT:
1157         case PTRACE_PEEKDATA:
1158                 /* read word at location addr */
1159                 if (access_process_vm(child, addr, &data, sizeof(data), 0)
1160                     != sizeof(data))
1161                         return -EIO;
1162                 /* ensure return value is not mistaken for error code */
1163                 force_successful_syscall_return();
1164                 return data;
1165
1166         /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1167          * by the generic ptrace_request().
1168          */
1169
1170         case PTRACE_PEEKUSR:
1171                 /* read the word at addr in the USER area */
1172                 if (access_uarea(child, addr, &data, 0) < 0)
1173                         return -EIO;
1174                 /* ensure return value is not mistaken for error code */
1175                 force_successful_syscall_return();
1176                 return data;
1177
1178         case PTRACE_POKEUSR:
1179                 /* write the word at addr in the USER area */
1180                 if (access_uarea(child, addr, &data, 1) < 0)
1181                         return -EIO;
1182                 return 0;
1183
1184         case PTRACE_OLD_GETSIGINFO:
1185                 /* for backwards-compatibility */
1186                 return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1187
1188         case PTRACE_OLD_SETSIGINFO:
1189                 /* for backwards-compatibility */
1190                 return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1191
1192         case PTRACE_GETREGS:
1193                 return ptrace_getregs(child,
1194                                       (struct pt_all_user_regs __user *) data);
1195
1196         case PTRACE_SETREGS:
1197                 return ptrace_setregs(child,
1198                                       (struct pt_all_user_regs __user *) data);
1199
1200         default:
1201                 return ptrace_request(child, request, addr, data);
1202         }
1203 }
1204
1205
1206 /* "asmlinkage" so the input arguments are preserved... */
1207
1208 asmlinkage long
1209 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1210                      long arg4, long arg5, long arg6, long arg7,
1211                      struct pt_regs regs)
1212 {
1213         if (test_thread_flag(TIF_SYSCALL_TRACE))
1214                 if (tracehook_report_syscall_entry(&regs))
1215                         return -ENOSYS;
1216
1217         /* copy user rbs to kernel rbs */
1218         if (test_thread_flag(TIF_RESTORE_RSE))
1219                 ia64_sync_krbs();
1220
1221
1222         audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
1223
1224         return 0;
1225 }
1226
1227 /* "asmlinkage" so the input arguments are preserved... */
1228
1229 asmlinkage void
1230 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1231                      long arg4, long arg5, long arg6, long arg7,
1232                      struct pt_regs regs)
1233 {
1234         int step;
1235
1236         audit_syscall_exit(&regs);
1237
1238         step = test_thread_flag(TIF_SINGLESTEP);
1239         if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1240                 tracehook_report_syscall_exit(&regs, step);
1241
1242         /* copy user rbs to kernel rbs */
1243         if (test_thread_flag(TIF_RESTORE_RSE))
1244                 ia64_sync_krbs();
1245 }
1246
1247 /* Utrace implementation starts here */
1248 struct regset_get {
1249         void *kbuf;
1250         void __user *ubuf;
1251 };
1252
1253 struct regset_set {
1254         const void *kbuf;
1255         const void __user *ubuf;
1256 };
1257
1258 struct regset_getset {
1259         struct task_struct *target;
1260         const struct user_regset *regset;
1261         union {
1262                 struct regset_get get;
1263                 struct regset_set set;
1264         } u;
1265         unsigned int pos;
1266         unsigned int count;
1267         int ret;
1268 };
1269
1270 static int
1271 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1272                 unsigned long addr, unsigned long *data, int write_access)
1273 {
1274         struct pt_regs *pt;
1275         unsigned long *ptr = NULL;
1276         int ret;
1277         char nat = 0;
1278
1279         pt = task_pt_regs(target);
1280         switch (addr) {
1281         case ELF_GR_OFFSET(1):
1282                 ptr = &pt->r1;
1283                 break;
1284         case ELF_GR_OFFSET(2):
1285         case ELF_GR_OFFSET(3):
1286                 ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2));
1287                 break;
1288         case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7):
1289                 if (write_access) {
1290                         /* read NaT bit first: */
1291                         unsigned long dummy;
1292
1293                         ret = unw_get_gr(info, addr/8, &dummy, &nat);
1294                         if (ret < 0)
1295                                 return ret;
1296                 }
1297                 return unw_access_gr(info, addr/8, data, &nat, write_access);
1298         case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11):
1299                 ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8);
1300                 break;
1301         case ELF_GR_OFFSET(12):
1302         case ELF_GR_OFFSET(13):
1303                 ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12);
1304                 break;
1305         case ELF_GR_OFFSET(14):
1306                 ptr = &pt->r14;
1307                 break;
1308         case ELF_GR_OFFSET(15):
1309                 ptr = &pt->r15;
1310         }
1311         if (write_access)
1312                 *ptr = *data;
1313         else
1314                 *data = *ptr;
1315         return 0;
1316 }
1317
1318 static int
1319 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1320                 unsigned long addr, unsigned long *data, int write_access)
1321 {
1322         struct pt_regs *pt;
1323         unsigned long *ptr = NULL;
1324
1325         pt = task_pt_regs(target);
1326         switch (addr) {
1327         case ELF_BR_OFFSET(0):
1328                 ptr = &pt->b0;
1329                 break;
1330         case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1331                 return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1332                                      data, write_access);
1333         case ELF_BR_OFFSET(6):
1334                 ptr = &pt->b6;
1335                 break;
1336         case ELF_BR_OFFSET(7):
1337                 ptr = &pt->b7;
1338         }
1339         if (write_access)
1340                 *ptr = *data;
1341         else
1342                 *data = *ptr;
1343         return 0;
1344 }
1345
1346 static int
1347 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1348                 unsigned long addr, unsigned long *data, int write_access)
1349 {
1350         struct pt_regs *pt;
1351         unsigned long cfm, urbs_end;
1352         unsigned long *ptr = NULL;
1353
1354         pt = task_pt_regs(target);
1355         if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1356                 switch (addr) {
1357                 case ELF_AR_RSC_OFFSET:
1358                         /* force PL3 */
1359                         if (write_access)
1360                                 pt->ar_rsc = *data | (3 << 2);
1361                         else
1362                                 *data = pt->ar_rsc;
1363                         return 0;
1364                 case ELF_AR_BSP_OFFSET:
1365                         /*
1366                          * By convention, we use PT_AR_BSP to refer to
1367                          * the end of the user-level backing store.
1368                          * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1369                          * to get the real value of ar.bsp at the time
1370                          * the kernel was entered.
1371                          *
1372                          * Furthermore, when changing the contents of
1373                          * PT_AR_BSP (or PT_CFM) while the task is
1374                          * blocked in a system call, convert the state
1375                          * so that the non-system-call exit
1376                          * path is used.  This ensures that the proper
1377                          * state will be picked up when resuming
1378                          * execution.  However, it *also* means that
1379                          * once we write PT_AR_BSP/PT_CFM, it won't be
1380                          * possible to modify the syscall arguments of
1381                          * the pending system call any longer.  This
1382                          * shouldn't be an issue because modifying
1383                          * PT_AR_BSP/PT_CFM generally implies that
1384                          * we're either abandoning the pending system
1385                          * call or that we defer it's re-execution
1386                          * (e.g., due to GDB doing an inferior
1387                          * function call).
1388                          */
1389                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1390                         if (write_access) {
1391                                 if (*data != urbs_end) {
1392                                         if (in_syscall(pt))
1393                                                 convert_to_non_syscall(target,
1394                                                                        pt,
1395                                                                        cfm);
1396                                         /*
1397                                          * Simulate user-level write
1398                                          * of ar.bsp:
1399                                          */
1400                                         pt->loadrs = 0;
1401                                         pt->ar_bspstore = *data;
1402                                 }
1403                         } else
1404                                 *data = urbs_end;
1405                         return 0;
1406                 case ELF_AR_BSPSTORE_OFFSET:
1407                         ptr = &pt->ar_bspstore;
1408                         break;
1409                 case ELF_AR_RNAT_OFFSET:
1410                         ptr = &pt->ar_rnat;
1411                         break;
1412                 case ELF_AR_CCV_OFFSET:
1413                         ptr = &pt->ar_ccv;
1414                         break;
1415                 case ELF_AR_UNAT_OFFSET:
1416                         ptr = &pt->ar_unat;
1417                         break;
1418                 case ELF_AR_FPSR_OFFSET:
1419                         ptr = &pt->ar_fpsr;
1420                         break;
1421                 case ELF_AR_PFS_OFFSET:
1422                         ptr = &pt->ar_pfs;
1423                         break;
1424                 case ELF_AR_LC_OFFSET:
1425                         return unw_access_ar(info, UNW_AR_LC, data,
1426                                              write_access);
1427                 case ELF_AR_EC_OFFSET:
1428                         return unw_access_ar(info, UNW_AR_EC, data,
1429                                              write_access);
1430                 case ELF_AR_CSD_OFFSET:
1431                         ptr = &pt->ar_csd;
1432                         break;
1433                 case ELF_AR_SSD_OFFSET:
1434                         ptr = &pt->ar_ssd;
1435                 }
1436         } else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1437                 switch (addr) {
1438                 case ELF_CR_IIP_OFFSET:
1439                         ptr = &pt->cr_iip;
1440                         break;
1441                 case ELF_CFM_OFFSET:
1442                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1443                         if (write_access) {
1444                                 if (((cfm ^ *data) & PFM_MASK) != 0) {
1445                                         if (in_syscall(pt))
1446                                                 convert_to_non_syscall(target,
1447                                                                        pt,
1448                                                                        cfm);
1449                                         pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1450                                                       | (*data & PFM_MASK));
1451                                 }
1452                         } else
1453                                 *data = cfm;
1454                         return 0;
1455                 case ELF_CR_IPSR_OFFSET:
1456                         if (write_access) {
1457                                 unsigned long tmp = *data;
1458                                 /* psr.ri==3 is a reserved value: SDM 2:25 */
1459                                 if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1460                                         tmp &= ~IA64_PSR_RI;
1461                                 pt->cr_ipsr = ((tmp & IPSR_MASK)
1462                                                | (pt->cr_ipsr & ~IPSR_MASK));
1463                         } else
1464                                 *data = (pt->cr_ipsr & IPSR_MASK);
1465                         return 0;
1466                 }
1467         } else if (addr == ELF_NAT_OFFSET)
1468                 return access_nat_bits(target, pt, info,
1469                                        data, write_access);
1470         else if (addr == ELF_PR_OFFSET)
1471                 ptr = &pt->pr;
1472         else
1473                 return -1;
1474
1475         if (write_access)
1476                 *ptr = *data;
1477         else
1478                 *data = *ptr;
1479
1480         return 0;
1481 }
1482
1483 static int
1484 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1485                 unsigned long addr, unsigned long *data, int write_access)
1486 {
1487         if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15))
1488                 return access_elf_gpreg(target, info, addr, data, write_access);
1489         else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1490                 return access_elf_breg(target, info, addr, data, write_access);
1491         else
1492                 return access_elf_areg(target, info, addr, data, write_access);
1493 }
1494
1495 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1496 {
1497         struct pt_regs *pt;
1498         struct regset_getset *dst = arg;
1499         elf_greg_t tmp[16];
1500         unsigned int i, index, min_copy;
1501
1502         if (unw_unwind_to_user(info) < 0)
1503                 return;
1504
1505         /*
1506          * coredump format:
1507          *      r0-r31
1508          *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1509          *      predicate registers (p0-p63)
1510          *      b0-b7
1511          *      ip cfm user-mask
1512          *      ar.rsc ar.bsp ar.bspstore ar.rnat
1513          *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1514          */
1515
1516
1517         /* Skip r0 */
1518         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1519                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1520                                                       &dst->u.get.kbuf,
1521                                                       &dst->u.get.ubuf,
1522                                                       0, ELF_GR_OFFSET(1));
1523                 if (dst->ret || dst->count == 0)
1524                         return;
1525         }
1526
1527         /* gr1 - gr15 */
1528         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1529                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1530                 min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
1531                          (dst->pos + dst->count) : ELF_GR_OFFSET(16);
1532                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1533                                 index++)
1534                         if (access_elf_reg(dst->target, info, i,
1535                                                 &tmp[index], 0) < 0) {
1536                                 dst->ret = -EIO;
1537                                 return;
1538                         }
1539                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1540                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1541                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1542                 if (dst->ret || dst->count == 0)
1543                         return;
1544         }
1545
1546         /* r16-r31 */
1547         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1548                 pt = task_pt_regs(dst->target);
1549                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1550                                 &dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
1551                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1552                 if (dst->ret || dst->count == 0)
1553                         return;
1554         }
1555
1556         /* nat, pr, b0 - b7 */
1557         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1558                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1559                 min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
1560                          (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
1561                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1562                                 index++)
1563                         if (access_elf_reg(dst->target, info, i,
1564                                                 &tmp[index], 0) < 0) {
1565                                 dst->ret = -EIO;
1566                                 return;
1567                         }
1568                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1569                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1570                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1571                 if (dst->ret || dst->count == 0)
1572                         return;
1573         }
1574
1575         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1576          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1577          */
1578         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1579                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1580                 min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
1581                          (dst->pos + dst->count) : ELF_AR_END_OFFSET;
1582                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1583                                 index++)
1584                         if (access_elf_reg(dst->target, info, i,
1585                                                 &tmp[index], 0) < 0) {
1586                                 dst->ret = -EIO;
1587                                 return;
1588                         }
1589                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1590                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1591                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1592         }
1593 }
1594
1595 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1596 {
1597         struct pt_regs *pt;
1598         struct regset_getset *dst = arg;
1599         elf_greg_t tmp[16];
1600         unsigned int i, index;
1601
1602         if (unw_unwind_to_user(info) < 0)
1603                 return;
1604
1605         /* Skip r0 */
1606         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1607                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1608                                                        &dst->u.set.kbuf,
1609                                                        &dst->u.set.ubuf,
1610                                                        0, ELF_GR_OFFSET(1));
1611                 if (dst->ret || dst->count == 0)
1612                         return;
1613         }
1614
1615         /* gr1-gr15 */
1616         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1617                 i = dst->pos;
1618                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1619                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1620                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1621                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1622                 if (dst->ret)
1623                         return;
1624                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1625                         if (access_elf_reg(dst->target, info, i,
1626                                                 &tmp[index], 1) < 0) {
1627                                 dst->ret = -EIO;
1628                                 return;
1629                         }
1630                 if (dst->count == 0)
1631                         return;
1632         }
1633
1634         /* gr16-gr31 */
1635         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1636                 pt = task_pt_regs(dst->target);
1637                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1638                                 &dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
1639                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1640                 if (dst->ret || dst->count == 0)
1641                         return;
1642         }
1643
1644         /* nat, pr, b0 - b7 */
1645         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1646                 i = dst->pos;
1647                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1648                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1649                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1650                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1651                 if (dst->ret)
1652                         return;
1653                 for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
1654                         if (access_elf_reg(dst->target, info, i,
1655                                                 &tmp[index], 1) < 0) {
1656                                 dst->ret = -EIO;
1657                                 return;
1658                         }
1659                 if (dst->count == 0)
1660                         return;
1661         }
1662
1663         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1664          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1665          */
1666         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1667                 i = dst->pos;
1668                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1669                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1670                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1671                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1672                 if (dst->ret)
1673                         return;
1674                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1675                         if (access_elf_reg(dst->target, info, i,
1676                                                 &tmp[index], 1) < 0) {
1677                                 dst->ret = -EIO;
1678                                 return;
1679                         }
1680         }
1681 }
1682
1683 #define ELF_FP_OFFSET(i)        (i * sizeof(elf_fpreg_t))
1684
1685 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1686 {
1687         struct regset_getset *dst = arg;
1688         struct task_struct *task = dst->target;
1689         elf_fpreg_t tmp[30];
1690         int index, min_copy, i;
1691
1692         if (unw_unwind_to_user(info) < 0)
1693                 return;
1694
1695         /* Skip pos 0 and 1 */
1696         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1697                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1698                                                       &dst->u.get.kbuf,
1699                                                       &dst->u.get.ubuf,
1700                                                       0, ELF_FP_OFFSET(2));
1701                 if (dst->count == 0 || dst->ret)
1702                         return;
1703         }
1704
1705         /* fr2-fr31 */
1706         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1707                 index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t);
1708
1709                 min_copy = min(((unsigned int)ELF_FP_OFFSET(32)),
1710                                 dst->pos + dst->count);
1711                 for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t),
1712                                 index++)
1713                         if (unw_get_fr(info, i / sizeof(elf_fpreg_t),
1714                                          &tmp[index])) {
1715                                 dst->ret = -EIO;
1716                                 return;
1717                         }
1718                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1719                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1720                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1721                 if (dst->count == 0 || dst->ret)
1722                         return;
1723         }
1724
1725         /* fph */
1726         if (dst->count > 0) {
1727                 ia64_flush_fph(dst->target);
1728                 if (task->thread.flags & IA64_THREAD_FPH_VALID)
1729                         dst->ret = user_regset_copyout(
1730                                 &dst->pos, &dst->count,
1731                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1732                                 &dst->target->thread.fph,
1733                                 ELF_FP_OFFSET(32), -1);
1734                 else
1735                         /* Zero fill instead.  */
1736                         dst->ret = user_regset_copyout_zero(
1737                                 &dst->pos, &dst->count,
1738                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1739                                 ELF_FP_OFFSET(32), -1);
1740         }
1741 }
1742
1743 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1744 {
1745         struct regset_getset *dst = arg;
1746         elf_fpreg_t fpreg, tmp[30];
1747         int index, start, end;
1748
1749         if (unw_unwind_to_user(info) < 0)
1750                 return;
1751
1752         /* Skip pos 0 and 1 */
1753         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1754                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1755                                                        &dst->u.set.kbuf,
1756                                                        &dst->u.set.ubuf,
1757                                                        0, ELF_FP_OFFSET(2));
1758                 if (dst->count == 0 || dst->ret)
1759                         return;
1760         }
1761
1762         /* fr2-fr31 */
1763         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1764                 start = dst->pos;
1765                 end = min(((unsigned int)ELF_FP_OFFSET(32)),
1766                          dst->pos + dst->count);
1767                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1768                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1769                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1770                 if (dst->ret)
1771                         return;
1772
1773                 if (start & 0xF) { /* only write high part */
1774                         if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1775                                          &fpreg)) {
1776                                 dst->ret = -EIO;
1777                                 return;
1778                         }
1779                         tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1780                                 = fpreg.u.bits[0];
1781                         start &= ~0xFUL;
1782                 }
1783                 if (end & 0xF) { /* only write low part */
1784                         if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1785                                         &fpreg)) {
1786                                 dst->ret = -EIO;
1787                                 return;
1788                         }
1789                         tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1790                                 = fpreg.u.bits[1];
1791                         end = (end + 0xF) & ~0xFUL;
1792                 }
1793
1794                 for ( ; start < end ; start += sizeof(elf_fpreg_t)) {
1795                         index = start / sizeof(elf_fpreg_t);
1796                         if (unw_set_fr(info, index, tmp[index - 2])) {
1797                                 dst->ret = -EIO;
1798                                 return;
1799                         }
1800                 }
1801                 if (dst->ret || dst->count == 0)
1802                         return;
1803         }
1804
1805         /* fph */
1806         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1807                 ia64_sync_fph(dst->target);
1808                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1809                                                 &dst->u.set.kbuf,
1810                                                 &dst->u.set.ubuf,
1811                                                 &dst->target->thread.fph,
1812                                                 ELF_FP_OFFSET(32), -1);
1813         }
1814 }
1815
1816 static int
1817 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1818                struct task_struct *target,
1819                const struct user_regset *regset,
1820                unsigned int pos, unsigned int count,
1821                const void *kbuf, const void __user *ubuf)
1822 {
1823         struct regset_getset info = { .target = target, .regset = regset,
1824                                  .pos = pos, .count = count,
1825                                  .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1826                                  .ret = 0 };
1827
1828         if (target == current)
1829                 unw_init_running(call, &info);
1830         else {
1831                 struct unw_frame_info ufi;
1832                 memset(&ufi, 0, sizeof(ufi));
1833                 unw_init_from_blocked_task(&ufi, target);
1834                 (*call)(&ufi, &info);
1835         }
1836
1837         return info.ret;
1838 }
1839
1840 static int
1841 gpregs_get(struct task_struct *target,
1842            const struct user_regset *regset,
1843            unsigned int pos, unsigned int count,
1844            void *kbuf, void __user *ubuf)
1845 {
1846         return do_regset_call(do_gpregs_get, target, regset, pos, count,
1847                 kbuf, ubuf);
1848 }
1849
1850 static int gpregs_set(struct task_struct *target,
1851                 const struct user_regset *regset,
1852                 unsigned int pos, unsigned int count,
1853                 const void *kbuf, const void __user *ubuf)
1854 {
1855         return do_regset_call(do_gpregs_set, target, regset, pos, count,
1856                 kbuf, ubuf);
1857 }
1858
1859 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1860 {
1861         do_sync_rbs(info, ia64_sync_user_rbs);
1862 }
1863
1864 /*
1865  * This is called to write back the register backing store.
1866  * ptrace does this before it stops, so that a tracer reading the user
1867  * memory after the thread stops will get the current register data.
1868  */
1869 static int
1870 gpregs_writeback(struct task_struct *target,
1871                  const struct user_regset *regset,
1872                  int now)
1873 {
1874         if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1875                 return 0;
1876         set_notify_resume(target);
1877         return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1878                 NULL, NULL);
1879 }
1880
1881 static int
1882 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1883 {
1884         return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1885 }
1886
1887 static int fpregs_get(struct task_struct *target,
1888                 const struct user_regset *regset,
1889                 unsigned int pos, unsigned int count,
1890                 void *kbuf, void __user *ubuf)
1891 {
1892         return do_regset_call(do_fpregs_get, target, regset, pos, count,
1893                 kbuf, ubuf);
1894 }
1895
1896 static int fpregs_set(struct task_struct *target,
1897                 const struct user_regset *regset,
1898                 unsigned int pos, unsigned int count,
1899                 const void *kbuf, const void __user *ubuf)
1900 {
1901         return do_regset_call(do_fpregs_set, target, regset, pos, count,
1902                 kbuf, ubuf);
1903 }
1904
1905 static int
1906 access_uarea(struct task_struct *child, unsigned long addr,
1907               unsigned long *data, int write_access)
1908 {
1909         unsigned int pos = -1; /* an invalid value */
1910         int ret;
1911         unsigned long *ptr, regnum;
1912
1913         if ((addr & 0x7) != 0) {
1914                 dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1915                 return -1;
1916         }
1917         if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1918                 (addr >= PT_R7 + 8 && addr < PT_B1) ||
1919                 (addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1920                 (addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1921                 dprintk("ptrace: rejecting access to register "
1922                                         "address 0x%lx\n", addr);
1923                 return -1;
1924         }
1925
1926         switch (addr) {
1927         case PT_F32 ... (PT_F127 + 15):
1928                 pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1929                 break;
1930         case PT_F2 ... (PT_F5 + 15):
1931                 pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1932                 break;
1933         case PT_F10 ... (PT_F31 + 15):
1934                 pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1935                 break;
1936         case PT_F6 ... (PT_F9 + 15):
1937                 pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1938                 break;
1939         }
1940
1941         if (pos != -1) {
1942                 if (write_access)
1943                         ret = fpregs_set(child, NULL, pos,
1944                                 sizeof(unsigned long), data, NULL);
1945                 else
1946                         ret = fpregs_get(child, NULL, pos,
1947                                 sizeof(unsigned long), data, NULL);
1948                 if (ret != 0)
1949                         return -1;
1950                 return 0;
1951         }
1952
1953         switch (addr) {
1954         case PT_NAT_BITS:
1955                 pos = ELF_NAT_OFFSET;
1956                 break;
1957         case PT_R4 ... PT_R7:
1958                 pos = addr - PT_R4 + ELF_GR_OFFSET(4);
1959                 break;
1960         case PT_B1 ... PT_B5:
1961                 pos = addr - PT_B1 + ELF_BR_OFFSET(1);
1962                 break;
1963         case PT_AR_EC:
1964                 pos = ELF_AR_EC_OFFSET;
1965                 break;
1966         case PT_AR_LC:
1967                 pos = ELF_AR_LC_OFFSET;
1968                 break;
1969         case PT_CR_IPSR:
1970                 pos = ELF_CR_IPSR_OFFSET;
1971                 break;
1972         case PT_CR_IIP:
1973                 pos = ELF_CR_IIP_OFFSET;
1974                 break;
1975         case PT_CFM:
1976                 pos = ELF_CFM_OFFSET;
1977                 break;
1978         case PT_AR_UNAT:
1979                 pos = ELF_AR_UNAT_OFFSET;
1980                 break;
1981         case PT_AR_PFS:
1982                 pos = ELF_AR_PFS_OFFSET;
1983                 break;
1984         case PT_AR_RSC:
1985                 pos = ELF_AR_RSC_OFFSET;
1986                 break;
1987         case PT_AR_RNAT:
1988                 pos = ELF_AR_RNAT_OFFSET;
1989                 break;
1990         case PT_AR_BSPSTORE:
1991                 pos = ELF_AR_BSPSTORE_OFFSET;
1992                 break;
1993         case PT_PR:
1994                 pos = ELF_PR_OFFSET;
1995                 break;
1996         case PT_B6:
1997                 pos = ELF_BR_OFFSET(6);
1998                 break;
1999         case PT_AR_BSP:
2000                 pos = ELF_AR_BSP_OFFSET;
2001                 break;
2002         case PT_R1 ... PT_R3:
2003                 pos = addr - PT_R1 + ELF_GR_OFFSET(1);
2004                 break;
2005         case PT_R12 ... PT_R15:
2006                 pos = addr - PT_R12 + ELF_GR_OFFSET(12);
2007                 break;
2008         case PT_R8 ... PT_R11:
2009                 pos = addr - PT_R8 + ELF_GR_OFFSET(8);
2010                 break;
2011         case PT_R16 ... PT_R31:
2012                 pos = addr - PT_R16 + ELF_GR_OFFSET(16);
2013                 break;
2014         case PT_AR_CCV:
2015                 pos = ELF_AR_CCV_OFFSET;
2016                 break;
2017         case PT_AR_FPSR:
2018                 pos = ELF_AR_FPSR_OFFSET;
2019                 break;
2020         case PT_B0:
2021                 pos = ELF_BR_OFFSET(0);
2022                 break;
2023         case PT_B7:
2024                 pos = ELF_BR_OFFSET(7);
2025                 break;
2026         case PT_AR_CSD:
2027                 pos = ELF_AR_CSD_OFFSET;
2028                 break;
2029         case PT_AR_SSD:
2030                 pos = ELF_AR_SSD_OFFSET;
2031                 break;
2032         }
2033
2034         if (pos != -1) {
2035                 if (write_access)
2036                         ret = gpregs_set(child, NULL, pos,
2037                                 sizeof(unsigned long), data, NULL);
2038                 else
2039                         ret = gpregs_get(child, NULL, pos,
2040                                 sizeof(unsigned long), data, NULL);
2041                 if (ret != 0)
2042                         return -1;
2043                 return 0;
2044         }
2045
2046         /* access debug registers */
2047         if (addr >= PT_IBR) {
2048                 regnum = (addr - PT_IBR) >> 3;
2049                 ptr = &child->thread.ibr[0];
2050         } else {
2051                 regnum = (addr - PT_DBR) >> 3;
2052                 ptr = &child->thread.dbr[0];
2053         }
2054
2055         if (regnum >= 8) {
2056                 dprintk("ptrace: rejecting access to register "
2057                                 "address 0x%lx\n", addr);
2058                 return -1;
2059         }
2060 #ifdef CONFIG_PERFMON
2061         /*
2062          * Check if debug registers are used by perfmon. This
2063          * test must be done once we know that we can do the
2064          * operation, i.e. the arguments are all valid, but
2065          * before we start modifying the state.
2066          *
2067          * Perfmon needs to keep a count of how many processes
2068          * are trying to modify the debug registers for system
2069          * wide monitoring sessions.
2070          *
2071          * We also include read access here, because they may
2072          * cause the PMU-installed debug register state
2073          * (dbr[], ibr[]) to be reset. The two arrays are also
2074          * used by perfmon, but we do not use
2075          * IA64_THREAD_DBG_VALID. The registers are restored
2076          * by the PMU context switch code.
2077          */
2078         if (pfm_use_debug_registers(child))
2079                 return -1;
2080 #endif
2081
2082         if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
2083                 child->thread.flags |= IA64_THREAD_DBG_VALID;
2084                 memset(child->thread.dbr, 0,
2085                                 sizeof(child->thread.dbr));
2086                 memset(child->thread.ibr, 0,
2087                                 sizeof(child->thread.ibr));
2088         }
2089
2090         ptr += regnum;
2091
2092         if ((regnum & 1) && write_access) {
2093                 /* don't let the user set kernel-level breakpoints: */
2094                 *ptr = *data & ~(7UL << 56);
2095                 return 0;
2096         }
2097         if (write_access)
2098                 *ptr = *data;
2099         else
2100                 *data = *ptr;
2101         return 0;
2102 }
2103
2104 static const struct user_regset native_regsets[] = {
2105         {
2106                 .core_note_type = NT_PRSTATUS,
2107                 .n = ELF_NGREG,
2108                 .size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2109                 .get = gpregs_get, .set = gpregs_set,
2110                 .writeback = gpregs_writeback
2111         },
2112         {
2113                 .core_note_type = NT_PRFPREG,
2114                 .n = ELF_NFPREG,
2115                 .size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2116                 .get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2117         },
2118 };
2119
2120 static const struct user_regset_view user_ia64_view = {
2121         .name = "ia64",
2122         .e_machine = EM_IA_64,
2123         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2124 };
2125
2126 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2127 {
2128         return &user_ia64_view;
2129 }
2130
2131 struct syscall_get_set_args {
2132         unsigned int i;
2133         unsigned int n;
2134         unsigned long *args;
2135         struct pt_regs *regs;
2136         int rw;
2137 };
2138
2139 static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2140 {
2141         struct syscall_get_set_args *args = data;
2142         struct pt_regs *pt = args->regs;
2143         unsigned long *krbs, cfm, ndirty;
2144         int i, count;
2145
2146         if (unw_unwind_to_user(info) < 0)
2147                 return;
2148
2149         cfm = pt->cr_ifs;
2150         krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2151         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2152
2153         count = 0;
2154         if (in_syscall(pt))
2155                 count = min_t(int, args->n, cfm & 0x7f);
2156
2157         for (i = 0; i < count; i++) {
2158                 if (args->rw)
2159                         *ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
2160                                 args->args[i];
2161                 else
2162                         args->args[i] = *ia64_rse_skip_regs(krbs,
2163                                 ndirty + i + args->i);
2164         }
2165
2166         if (!args->rw) {
2167                 while (i < args->n) {
2168                         args->args[i] = 0;
2169                         i++;
2170                 }
2171         }
2172 }
2173
2174 void ia64_syscall_get_set_arguments(struct task_struct *task,
2175         struct pt_regs *regs, unsigned int i, unsigned int n,
2176         unsigned long *args, int rw)
2177 {
2178         struct syscall_get_set_args data = {
2179                 .i = i,
2180                 .n = n,
2181                 .args = args,
2182                 .regs = regs,
2183                 .rw = rw,
2184         };
2185
2186         if (task == current)
2187                 unw_init_running(syscall_get_set_args_cb, &data);
2188         else {
2189                 struct unw_frame_info ufi;
2190                 memset(&ufi, 0, sizeof(ufi));
2191                 unw_init_from_blocked_task(&ufi, task);
2192                 syscall_get_set_args_cb(&ufi, &data);
2193         }
2194 }