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 <[email protected]>
   6  * Copyright (C) 2006 Intel Co
   7  *  2006-08-12  - IA64 Native Utrace implementation support added by
   8  *      Anil S Keshavamurthy <[email protected]>
   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 <linux/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), FOLL_FORCE);
 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),
 493                                 FOLL_FORCE | FOLL_WRITE)
 494                    != sizeof(val))
 495                 return -EIO;
 496         return 0;
 497 }
 498
 499 /*
 500  * Calculate the address of the end of the user-level register backing
 501  * store.  This is the address that would have been stored in ar.bsp
 502  * if the user had executed a "cover" instruction right before
 503  * entering the kernel.  If CFMP is not NULL, it is used to return the
 504  * "current frame mask" that was active at the time the kernel was
 505  * entered.
 506  */
 507 unsigned long
 508 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
 509                        unsigned long *cfmp)
 510 {
 511         unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
 512         long ndirty;
 513
 514         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 515         bspstore = (unsigned long *) pt->ar_bspstore;
 516         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
 517
 518         if (in_syscall(pt))
 519                 ndirty += (cfm & 0x7f);
 520         else
 521                 cfm &= ~(1UL << 63);    /* clear valid bit */
 522
 523         if (cfmp)
 524                 *cfmp = cfm;
 525         return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
 526 }
 527
 528 /*
 529  * Synchronize (i.e, write) the RSE backing store living in kernel
 530  * space to the VM of the CHILD task.  SW and PT are the pointers to
 531  * the switch_stack and pt_regs structures, respectively.
 532  * USER_RBS_END is the user-level address at which the backing store
 533  * ends.
 534  */
 535 long
 536 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
 537                     unsigned long user_rbs_start, unsigned long user_rbs_end)
 538 {
 539         unsigned long addr, val;
 540         long ret;
 541
 542         /* now copy word for word from kernel rbs to user rbs: */
 543         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 544                 ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
 545                 if (ret < 0)
 546                         return ret;
 547                 if (access_process_vm(child, addr, &val, sizeof(val),
 548                                 FOLL_FORCE | FOLL_WRITE)
 549                     != sizeof(val))
 550                         return -EIO;
 551         }
 552         return 0;
 553 }
 554
 555 static long
 556 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
 557                 unsigned long user_rbs_start, unsigned long user_rbs_end)
 558 {
 559         unsigned long addr, val;
 560         long ret;
 561
 562         /* now copy word for word from user rbs to kernel rbs: */
 563         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 564                 if (access_process_vm(child, addr, &val, sizeof(val),
 565                                 FOLL_FORCE)
 566                                 != sizeof(val))
 567                         return -EIO;
 568
 569                 ret = ia64_poke(child, sw, user_rbs_end, addr, val);
 570                 if (ret < 0)
 571                         return ret;
 572         }
 573         return 0;
 574 }
 575
 576 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
 577                             unsigned long, unsigned long);
 578
 579 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
 580 {
 581         struct pt_regs *pt;
 582         unsigned long urbs_end;
 583         syncfunc_t fn = arg;
 584
 585         if (unw_unwind_to_user(info) < 0)
 586                 return;
 587         pt = task_pt_regs(info->task);
 588         urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
 589
 590         fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
 591 }
 592
 593 /*
 594  * when a thread is stopped (ptraced), debugger might change thread's user
 595  * stack (change memory directly), and we must avoid the RSE stored in kernel
 596  * to override user stack (user space's RSE is newer than kernel's in the
 597  * case). To workaround the issue, we copy kernel RSE to user RSE before the
 598  * task is stopped, so user RSE has updated data.  we then copy user RSE to
 599  * kernel after the task is resummed from traced stop and kernel will use the
 600  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
 601  * synchronize user RSE to kernel.
 602  */
 603 void ia64_ptrace_stop(void)
 604 {
 605         if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
 606                 return;
 607         set_notify_resume(current);
 608         unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
 609 }
 610
 611 /*
 612  * This is called to read back the register backing store.
 613  */
 614 void ia64_sync_krbs(void)
 615 {
 616         clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
 617
 618         unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
 619 }
 620
 621 /*
 622  * After PTRACE_ATTACH, a thread's register backing store area in user
 623  * space is assumed to contain correct data whenever the thread is
 624  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
 625  * But if the child was already stopped for job control when we attach
 626  * to it, then it might not ever get into ptrace_stop by the time we
 627  * want to examine the user memory containing the RBS.
 628  */
 629 void
 630 ptrace_attach_sync_user_rbs (struct task_struct *child)
 631 {
 632         int stopped = 0;
 633         struct unw_frame_info info;
 634
 635         /*
 636          * If the child is in TASK_STOPPED, we need to change that to
 637          * TASK_TRACED momentarily while we operate on it.  This ensures
 638          * that the child won't be woken up and return to user mode while
 639          * we are doing the sync.  (It can only be woken up for SIGKILL.)
 640          */
 641
 642         read_lock(&tasklist_lock);
 643         if (child->sighand) {
 644                 spin_lock_irq(&child->sighand->siglock);
 645                 if (child->state == TASK_STOPPED &&
 646                     !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
 647                         set_notify_resume(child);
 648
 649                         child->state = TASK_TRACED;
 650                         stopped = 1;
 651                 }
 652                 spin_unlock_irq(&child->sighand->siglock);
 653         }
 654         read_unlock(&tasklist_lock);
 655
 656         if (!stopped)
 657                 return;
 658
 659         unw_init_from_blocked_task(&info, child);
 660         do_sync_rbs(&info, ia64_sync_user_rbs);
 661
 662         /*
 663          * Now move the child back into TASK_STOPPED if it should be in a
 664          * job control stop, so that SIGCONT can be used to wake it up.
 665          */
 666         read_lock(&tasklist_lock);
 667         if (child->sighand) {
 668                 spin_lock_irq(&child->sighand->siglock);
 669                 if (child->state == TASK_TRACED &&
 670                     (child->signal->flags & SIGNAL_STOP_STOPPED)) {
 671                         child->state = TASK_STOPPED;
 672                 }
 673                 spin_unlock_irq(&child->sighand->siglock);
 674         }
 675         read_unlock(&tasklist_lock);
 676 }
 677
 678 /*
 679  * Write f32-f127 back to task->thread.fph if it has been modified.
 680  */
 681 inline void
 682 ia64_flush_fph (struct task_struct *task)
 683 {
 684         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 685
 686         /*
 687          * Prevent migrating this task while
 688          * we're fiddling with the FPU state
 689          */
 690         preempt_disable();
 691         if (ia64_is_local_fpu_owner(task) && psr->mfh) {
 692                 psr->mfh = 0;
 693                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 694                 ia64_save_fpu(&task->thread.fph[0]);
 695         }
 696         preempt_enable();
 697 }
 698
 699 /*
 700  * Sync the fph state of the task so that it can be manipulated
 701  * through thread.fph.  If necessary, f32-f127 are written back to
 702  * thread.fph or, if the fph state hasn't been used before, thread.fph
 703  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
 704  * ensure that the task picks up the state from thread.fph when it
 705  * executes again.
 706  */
 707 void
 708 ia64_sync_fph (struct task_struct *task)
 709 {
 710         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 711
 712         ia64_flush_fph(task);
 713         if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
 714                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 715                 memset(&task->thread.fph, 0, sizeof(task->thread.fph));
 716         }
 717         ia64_drop_fpu(task);
 718         psr->dfh = 1;
 719 }
 720
 721 /*
 722  * Change the machine-state of CHILD such that it will return via the normal
 723  * kernel exit-path, rather than the syscall-exit path.
 724  */
 725 static void
 726 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
 727                         unsigned long cfm)
 728 {
 729         struct unw_frame_info info, prev_info;
 730         unsigned long ip, sp, pr;
 731
 732         unw_init_from_blocked_task(&info, child);
 733         while (1) {
 734                 prev_info = info;
 735                 if (unw_unwind(&info) < 0)
 736                         return;
 737
 738                 unw_get_sp(&info, &sp);
 739                 if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
 740                     < IA64_PT_REGS_SIZE) {
 741                         dprintk("ptrace.%s: ran off the top of the kernel "
 742                                 "stack\n", __func__);
 743                         return;
 744                 }
 745                 if (unw_get_pr (&prev_info, &pr) < 0) {
 746                         unw_get_rp(&prev_info, &ip);
 747                         dprintk("ptrace.%s: failed to read "
 748                                 "predicate register (ip=0x%lx)\n",
 749                                 __func__, ip);
 750                         return;
 751                 }
 752                 if (unw_is_intr_frame(&info)
 753                     && (pr & (1UL << PRED_USER_STACK)))
 754                         break;
 755         }
 756
 757         /*
 758          * Note: at the time of this call, the target task is blocked
 759          * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
 760          * (aka, "pLvSys") we redirect execution from
 761          * .work_pending_syscall_end to .work_processed_kernel.
 762          */
 763         unw_get_pr(&prev_info, &pr);
 764         pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
 765         pr |=  (1UL << PRED_NON_SYSCALL);
 766         unw_set_pr(&prev_info, pr);
 767
 768         pt->cr_ifs = (1UL << 63) | cfm;
 769         /*
 770          * Clear the memory that is NOT written on syscall-entry to
 771          * ensure we do not leak kernel-state to user when execution
 772          * resumes.
 773          */
 774         pt->r2 = 0;
 775         pt->r3 = 0;
 776         pt->r14 = 0;
 777         memset(&pt->r16, 0, 16*8);      /* clear r16-r31 */
 778         memset(&pt->f6, 0, 6*16);       /* clear f6-f11 */
 779         pt->b7 = 0;
 780         pt->ar_ccv = 0;
 781         pt->ar_csd = 0;
 782         pt->ar_ssd = 0;
 783 }
 784
 785 static int
 786 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
 787                  struct unw_frame_info *info,
 788                  unsigned long *data, int write_access)
 789 {
 790         unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
 791         char nat = 0;
 792
 793         if (write_access) {
 794                 nat_bits = *data;
 795                 scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
 796                 if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
 797                         dprintk("ptrace: failed to set ar.unat\n");
 798                         return -1;
 799                 }
 800                 for (regnum = 4; regnum <= 7; ++regnum) {
 801                         unw_get_gr(info, regnum, &dummy, &nat);
 802                         unw_set_gr(info, regnum, dummy,
 803                                    (nat_bits >> regnum) & 1);
 804                 }
 805         } else {
 806                 if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
 807                         dprintk("ptrace: failed to read ar.unat\n");
 808                         return -1;
 809                 }
 810                 nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
 811                 for (regnum = 4; regnum <= 7; ++regnum) {
 812                         unw_get_gr(info, regnum, &dummy, &nat);
 813                         nat_bits |= (nat != 0) << regnum;
 814                 }
 815                 *data = nat_bits;
 816         }
 817         return 0;
 818 }
 819
 820 static int
 821 access_uarea (struct task_struct *child, unsigned long addr,
 822               unsigned long *data, int write_access);
 823
 824 static long
 825 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 826 {
 827         unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
 828         struct unw_frame_info info;
 829         struct ia64_fpreg fpval;
 830         struct switch_stack *sw;
 831         struct pt_regs *pt;
 832         long ret, retval = 0;
 833         char nat = 0;
 834         int i;
 835
 836         if (!access_ok(VERIFY_WRITE, ppr, sizeof(struct pt_all_user_regs)))
 837                 return -EIO;
 838
 839         pt = task_pt_regs(child);
 840         sw = (struct switch_stack *) (child->thread.ksp + 16);
 841         unw_init_from_blocked_task(&info, child);
 842         if (unw_unwind_to_user(&info) < 0) {
 843                 return -EIO;
 844         }
 845
 846         if (((unsigned long) ppr & 0x7) != 0) {
 847                 dprintk("ptrace:unaligned register address %p\n", ppr);
 848                 return -EIO;
 849         }
 850
 851         if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
 852             || access_uarea(child, PT_AR_EC, &ec, 0) < 0
 853             || access_uarea(child, PT_AR_LC, &lc, 0) < 0
 854             || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
 855             || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
 856             || access_uarea(child, PT_CFM, &cfm, 0)
 857             || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
 858                 return -EIO;
 859
 860         /* control regs */
 861
 862         retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
 863         retval |= __put_user(psr, &ppr->cr_ipsr);
 864
 865         /* app regs */
 866
 867         retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
 868         retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
 869         retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
 870         retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
 871         retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
 872         retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
 873
 874         retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
 875         retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
 876         retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
 877         retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
 878         retval |= __put_user(cfm, &ppr->cfm);
 879
 880         /* gr1-gr3 */
 881
 882         retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
 883         retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
 884
 885         /* gr4-gr7 */
 886
 887         for (i = 4; i < 8; i++) {
 888                 if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
 889                         return -EIO;
 890                 retval |= __put_user(val, &ppr->gr[i]);
 891         }
 892
 893         /* gr8-gr11 */
 894
 895         retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
 896
 897         /* gr12-gr15 */
 898
 899         retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
 900         retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
 901         retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
 902
 903         /* gr16-gr31 */
 904
 905         retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
 906
 907         /* b0 */
 908
 909         retval |= __put_user(pt->b0, &ppr->br[0]);
 910
 911         /* b1-b5 */
 912
 913         for (i = 1; i < 6; i++) {
 914                 if (unw_access_br(&info, i, &val, 0) < 0)
 915                         return -EIO;
 916                 __put_user(val, &ppr->br[i]);
 917         }
 918
 919         /* b6-b7 */
 920
 921         retval |= __put_user(pt->b6, &ppr->br[6]);
 922         retval |= __put_user(pt->b7, &ppr->br[7]);
 923
 924         /* fr2-fr5 */
 925
 926         for (i = 2; i < 6; i++) {
 927                 if (unw_get_fr(&info, i, &fpval) < 0)
 928                         return -EIO;
 929                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 930         }
 931
 932         /* fr6-fr11 */
 933
 934         retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
 935                                  sizeof(struct ia64_fpreg) * 6);
 936
 937         /* fp scratch regs(12-15) */
 938
 939         retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
 940                                  sizeof(struct ia64_fpreg) * 4);
 941
 942         /* fr16-fr31 */
 943
 944         for (i = 16; i < 32; i++) {
 945                 if (unw_get_fr(&info, i, &fpval) < 0)
 946                         return -EIO;
 947                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 948         }
 949
 950         /* fph */
 951
 952         ia64_flush_fph(child);
 953         retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
 954                                  sizeof(ppr->fr[32]) * 96);
 955
 956         /*  preds */
 957
 958         retval |= __put_user(pt->pr, &ppr->pr);
 959
 960         /* nat bits */
 961
 962         retval |= __put_user(nat_bits, &ppr->nat);
 963
 964         ret = retval ? -EIO : 0;
 965         return ret;
 966 }
 967
 968 static long
 969 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 970 {
 971         unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
 972         struct unw_frame_info info;
 973         struct switch_stack *sw;
 974         struct ia64_fpreg fpval;
 975         struct pt_regs *pt;
 976         long ret, retval = 0;
 977         int i;
 978
 979         memset(&fpval, 0, sizeof(fpval));
 980
 981         if (!access_ok(VERIFY_READ, ppr, sizeof(struct pt_all_user_regs)))
 982                 return -EIO;
 983
 984         pt = task_pt_regs(child);
 985         sw = (struct switch_stack *) (child->thread.ksp + 16);
 986         unw_init_from_blocked_task(&info, child);
 987         if (unw_unwind_to_user(&info) < 0) {
 988                 return -EIO;
 989         }
 990
 991         if (((unsigned long) ppr & 0x7) != 0) {
 992                 dprintk("ptrace:unaligned register address %p\n", ppr);
 993                 return -EIO;
 994         }
 995
 996         /* control regs */
 997
 998         retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
 999         retval |= __get_user(psr, &ppr->cr_ipsr);
1000
1001         /* app regs */
1002
1003         retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1004         retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1005         retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1006         retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1007         retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1008         retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1009
1010         retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1011         retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1012         retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1013         retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1014         retval |= __get_user(cfm, &ppr->cfm);
1015
1016         /* gr1-gr3 */
1017
1018         retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1019         retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1020
1021         /* gr4-gr7 */
1022
1023         for (i = 4; i < 8; i++) {
1024                 retval |= __get_user(val, &ppr->gr[i]);
1025                 /* NaT bit will be set via PT_NAT_BITS: */
1026                 if (unw_set_gr(&info, i, val, 0) < 0)
1027                         return -EIO;
1028         }
1029
1030         /* gr8-gr11 */
1031
1032         retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1033
1034         /* gr12-gr15 */
1035
1036         retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1037         retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1038         retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1039
1040         /* gr16-gr31 */
1041
1042         retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1043
1044         /* b0 */
1045
1046         retval |= __get_user(pt->b0, &ppr->br[0]);
1047
1048         /* b1-b5 */
1049
1050         for (i = 1; i < 6; i++) {
1051                 retval |= __get_user(val, &ppr->br[i]);
1052                 unw_set_br(&info, i, val);
1053         }
1054
1055         /* b6-b7 */
1056
1057         retval |= __get_user(pt->b6, &ppr->br[6]);
1058         retval |= __get_user(pt->b7, &ppr->br[7]);
1059
1060         /* fr2-fr5 */
1061
1062         for (i = 2; i < 6; i++) {
1063                 retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1064                 if (unw_set_fr(&info, i, fpval) < 0)
1065                         return -EIO;
1066         }
1067
1068         /* fr6-fr11 */
1069
1070         retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1071                                    sizeof(ppr->fr[6]) * 6);
1072
1073         /* fp scratch regs(12-15) */
1074
1075         retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1076                                    sizeof(ppr->fr[12]) * 4);
1077
1078         /* fr16-fr31 */
1079
1080         for (i = 16; i < 32; i++) {
1081                 retval |= __copy_from_user(&fpval, &ppr->fr[i],
1082                                            sizeof(fpval));
1083                 if (unw_set_fr(&info, i, fpval) < 0)
1084                         return -EIO;
1085         }
1086
1087         /* fph */
1088
1089         ia64_sync_fph(child);
1090         retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1091                                    sizeof(ppr->fr[32]) * 96);
1092
1093         /* preds */
1094
1095         retval |= __get_user(pt->pr, &ppr->pr);
1096
1097         /* nat bits */
1098
1099         retval |= __get_user(nat_bits, &ppr->nat);
1100
1101         retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1102         retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1103         retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1104         retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1105         retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1106         retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1107         retval |= access_uarea(child, PT_CFM, &cfm, 1);
1108         retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1109
1110         ret = retval ? -EIO : 0;
1111         return ret;
1112 }
1113
1114 void
1115 user_enable_single_step (struct task_struct *child)
1116 {
1117         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1118
1119         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1120         child_psr->ss = 1;
1121 }
1122
1123 void
1124 user_enable_block_step (struct task_struct *child)
1125 {
1126         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1127
1128         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1129         child_psr->tb = 1;
1130 }
1131
1132 void
1133 user_disable_single_step (struct task_struct *child)
1134 {
1135         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1136
1137         /* make sure the single step/taken-branch trap bits are not set: */
1138         clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1139         child_psr->ss = 0;
1140         child_psr->tb = 0;
1141 }
1142
1143 /*
1144  * Called by kernel/ptrace.c when detaching..
1145  *
1146  * Make sure the single step bit is not set.
1147  */
1148 void
1149 ptrace_disable (struct task_struct *child)
1150 {
1151         user_disable_single_step(child);
1152 }
1153
1154 long
1155 arch_ptrace (struct task_struct *child, long request,
1156              unsigned long addr, unsigned long data)
1157 {
1158         switch (request) {
1159         case PTRACE_PEEKTEXT:
1160         case PTRACE_PEEKDATA:
1161                 /* read word at location addr */
1162                 if (ptrace_access_vm(child, addr, &data, sizeof(data),
1163                                 FOLL_FORCE)
1164                     != sizeof(data))
1165                         return -EIO;
1166                 /* ensure return value is not mistaken for error code */
1167                 force_successful_syscall_return();
1168                 return data;
1169
1170         /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1171          * by the generic ptrace_request().
1172          */
1173
1174         case PTRACE_PEEKUSR:
1175                 /* read the word at addr in the USER area */
1176                 if (access_uarea(child, addr, &data, 0) < 0)
1177                         return -EIO;
1178                 /* ensure return value is not mistaken for error code */
1179                 force_successful_syscall_return();
1180                 return data;
1181
1182         case PTRACE_POKEUSR:
1183                 /* write the word at addr in the USER area */
1184                 if (access_uarea(child, addr, &data, 1) < 0)
1185                         return -EIO;
1186                 return 0;
1187
1188         case PTRACE_OLD_GETSIGINFO:
1189                 /* for backwards-compatibility */
1190                 return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1191
1192         case PTRACE_OLD_SETSIGINFO:
1193                 /* for backwards-compatibility */
1194                 return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1195
1196         case PTRACE_GETREGS:
1197                 return ptrace_getregs(child,
1198                                       (struct pt_all_user_regs __user *) data);
1199
1200         case PTRACE_SETREGS:
1201                 return ptrace_setregs(child,
1202                                       (struct pt_all_user_regs __user *) data);
1203
1204         default:
1205                 return ptrace_request(child, request, addr, data);
1206         }
1207 }
1208
1209
1210 /* "asmlinkage" so the input arguments are preserved... */
1211
1212 asmlinkage long
1213 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1214                      long arg4, long arg5, long arg6, long arg7,
1215                      struct pt_regs regs)
1216 {
1217         if (test_thread_flag(TIF_SYSCALL_TRACE))
1218                 if (tracehook_report_syscall_entry(&regs))
1219                         return -ENOSYS;
1220
1221         /* copy user rbs to kernel rbs */
1222         if (test_thread_flag(TIF_RESTORE_RSE))
1223                 ia64_sync_krbs();
1224
1225
1226         audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
1227
1228         return 0;
1229 }
1230
1231 /* "asmlinkage" so the input arguments are preserved... */
1232
1233 asmlinkage void
1234 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1235                      long arg4, long arg5, long arg6, long arg7,
1236                      struct pt_regs regs)
1237 {
1238         int step;
1239
1240         audit_syscall_exit(&regs);
1241
1242         step = test_thread_flag(TIF_SINGLESTEP);
1243         if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1244                 tracehook_report_syscall_exit(&regs, step);
1245
1246         /* copy user rbs to kernel rbs */
1247         if (test_thread_flag(TIF_RESTORE_RSE))
1248                 ia64_sync_krbs();
1249 }
1250
1251 /* Utrace implementation starts here */
1252 struct regset_get {
1253         void *kbuf;
1254         void __user *ubuf;
1255 };
1256
1257 struct regset_set {
1258         const void *kbuf;
1259         const void __user *ubuf;
1260 };
1261
1262 struct regset_getset {
1263         struct task_struct *target;
1264         const struct user_regset *regset;
1265         union {
1266                 struct regset_get get;
1267                 struct regset_set set;
1268         } u;
1269         unsigned int pos;
1270         unsigned int count;
1271         int ret;
1272 };
1273
1274 static int
1275 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1276                 unsigned long addr, unsigned long *data, int write_access)
1277 {
1278         struct pt_regs *pt;
1279         unsigned long *ptr = NULL;
1280         int ret;
1281         char nat = 0;
1282
1283         pt = task_pt_regs(target);
1284         switch (addr) {
1285         case ELF_GR_OFFSET(1):
1286                 ptr = &pt->r1;
1287                 break;
1288         case ELF_GR_OFFSET(2):
1289         case ELF_GR_OFFSET(3):
1290                 ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2));
1291                 break;
1292         case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7):
1293                 if (write_access) {
1294                         /* read NaT bit first: */
1295                         unsigned long dummy;
1296
1297                         ret = unw_get_gr(info, addr/8, &dummy, &nat);
1298                         if (ret < 0)
1299                                 return ret;
1300                 }
1301                 return unw_access_gr(info, addr/8, data, &nat, write_access);
1302         case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11):
1303                 ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8);
1304                 break;
1305         case ELF_GR_OFFSET(12):
1306         case ELF_GR_OFFSET(13):
1307                 ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12);
1308                 break;
1309         case ELF_GR_OFFSET(14):
1310                 ptr = &pt->r14;
1311                 break;
1312         case ELF_GR_OFFSET(15):
1313                 ptr = &pt->r15;
1314         }
1315         if (write_access)
1316                 *ptr = *data;
1317         else
1318                 *data = *ptr;
1319         return 0;
1320 }
1321
1322 static int
1323 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1324                 unsigned long addr, unsigned long *data, int write_access)
1325 {
1326         struct pt_regs *pt;
1327         unsigned long *ptr = NULL;
1328
1329         pt = task_pt_regs(target);
1330         switch (addr) {
1331         case ELF_BR_OFFSET(0):
1332                 ptr = &pt->b0;
1333                 break;
1334         case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1335                 return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1336                                      data, write_access);
1337         case ELF_BR_OFFSET(6):
1338                 ptr = &pt->b6;
1339                 break;
1340         case ELF_BR_OFFSET(7):
1341                 ptr = &pt->b7;
1342         }
1343         if (write_access)
1344                 *ptr = *data;
1345         else
1346                 *data = *ptr;
1347         return 0;
1348 }
1349
1350 static int
1351 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1352                 unsigned long addr, unsigned long *data, int write_access)
1353 {
1354         struct pt_regs *pt;
1355         unsigned long cfm, urbs_end;
1356         unsigned long *ptr = NULL;
1357
1358         pt = task_pt_regs(target);
1359         if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1360                 switch (addr) {
1361                 case ELF_AR_RSC_OFFSET:
1362                         /* force PL3 */
1363                         if (write_access)
1364                                 pt->ar_rsc = *data | (3 << 2);
1365                         else
1366                                 *data = pt->ar_rsc;
1367                         return 0;
1368                 case ELF_AR_BSP_OFFSET:
1369                         /*
1370                          * By convention, we use PT_AR_BSP to refer to
1371                          * the end of the user-level backing store.
1372                          * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1373                          * to get the real value of ar.bsp at the time
1374                          * the kernel was entered.
1375                          *
1376                          * Furthermore, when changing the contents of
1377                          * PT_AR_BSP (or PT_CFM) while the task is
1378                          * blocked in a system call, convert the state
1379                          * so that the non-system-call exit
1380                          * path is used.  This ensures that the proper
1381                          * state will be picked up when resuming
1382                          * execution.  However, it *also* means that
1383                          * once we write PT_AR_BSP/PT_CFM, it won't be
1384                          * possible to modify the syscall arguments of
1385                          * the pending system call any longer.  This
1386                          * shouldn't be an issue because modifying
1387                          * PT_AR_BSP/PT_CFM generally implies that
1388                          * we're either abandoning the pending system
1389                          * call or that we defer it's re-execution
1390                          * (e.g., due to GDB doing an inferior
1391                          * function call).
1392                          */
1393                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1394                         if (write_access) {
1395                                 if (*data != urbs_end) {
1396                                         if (in_syscall(pt))
1397                                                 convert_to_non_syscall(target,
1398                                                                        pt,
1399                                                                        cfm);
1400                                         /*
1401                                          * Simulate user-level write
1402                                          * of ar.bsp:
1403                                          */
1404                                         pt->loadrs = 0;
1405                                         pt->ar_bspstore = *data;
1406                                 }
1407                         } else
1408                                 *data = urbs_end;
1409                         return 0;
1410                 case ELF_AR_BSPSTORE_OFFSET:
1411                         ptr = &pt->ar_bspstore;
1412                         break;
1413                 case ELF_AR_RNAT_OFFSET:
1414                         ptr = &pt->ar_rnat;
1415                         break;
1416                 case ELF_AR_CCV_OFFSET:
1417                         ptr = &pt->ar_ccv;
1418                         break;
1419                 case ELF_AR_UNAT_OFFSET:
1420                         ptr = &pt->ar_unat;
1421                         break;
1422                 case ELF_AR_FPSR_OFFSET:
1423                         ptr = &pt->ar_fpsr;
1424                         break;
1425                 case ELF_AR_PFS_OFFSET:
1426                         ptr = &pt->ar_pfs;
1427                         break;
1428                 case ELF_AR_LC_OFFSET:
1429                         return unw_access_ar(info, UNW_AR_LC, data,
1430                                              write_access);
1431                 case ELF_AR_EC_OFFSET:
1432                         return unw_access_ar(info, UNW_AR_EC, data,
1433                                              write_access);
1434                 case ELF_AR_CSD_OFFSET:
1435                         ptr = &pt->ar_csd;
1436                         break;
1437                 case ELF_AR_SSD_OFFSET:
1438                         ptr = &pt->ar_ssd;
1439                 }
1440         } else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1441                 switch (addr) {
1442                 case ELF_CR_IIP_OFFSET:
1443                         ptr = &pt->cr_iip;
1444                         break;
1445                 case ELF_CFM_OFFSET:
1446                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1447                         if (write_access) {
1448                                 if (((cfm ^ *data) & PFM_MASK) != 0) {
1449                                         if (in_syscall(pt))
1450                                                 convert_to_non_syscall(target,
1451                                                                        pt,
1452                                                                        cfm);
1453                                         pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1454                                                       | (*data & PFM_MASK));
1455                                 }
1456                         } else
1457                                 *data = cfm;
1458                         return 0;
1459                 case ELF_CR_IPSR_OFFSET:
1460                         if (write_access) {
1461                                 unsigned long tmp = *data;
1462                                 /* psr.ri==3 is a reserved value: SDM 2:25 */
1463                                 if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1464                                         tmp &= ~IA64_PSR_RI;
1465                                 pt->cr_ipsr = ((tmp & IPSR_MASK)
1466                                                | (pt->cr_ipsr & ~IPSR_MASK));
1467                         } else
1468                                 *data = (pt->cr_ipsr & IPSR_MASK);
1469                         return 0;
1470                 }
1471         } else if (addr == ELF_NAT_OFFSET)
1472                 return access_nat_bits(target, pt, info,
1473                                        data, write_access);
1474         else if (addr == ELF_PR_OFFSET)
1475                 ptr = &pt->pr;
1476         else
1477                 return -1;
1478
1479         if (write_access)
1480                 *ptr = *data;
1481         else
1482                 *data = *ptr;
1483
1484         return 0;
1485 }
1486
1487 static int
1488 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1489                 unsigned long addr, unsigned long *data, int write_access)
1490 {
1491         if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15))
1492                 return access_elf_gpreg(target, info, addr, data, write_access);
1493         else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1494                 return access_elf_breg(target, info, addr, data, write_access);
1495         else
1496                 return access_elf_areg(target, info, addr, data, write_access);
1497 }
1498
1499 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1500 {
1501         struct pt_regs *pt;
1502         struct regset_getset *dst = arg;
1503         elf_greg_t tmp[16];
1504         unsigned int i, index, min_copy;
1505
1506         if (unw_unwind_to_user(info) < 0)
1507                 return;
1508
1509         /*
1510          * coredump format:
1511          *      r0-r31
1512          *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1513          *      predicate registers (p0-p63)
1514          *      b0-b7
1515          *      ip cfm user-mask
1516          *      ar.rsc ar.bsp ar.bspstore ar.rnat
1517          *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1518          */
1519
1520
1521         /* Skip r0 */
1522         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1523                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1524                                                       &dst->u.get.kbuf,
1525                                                       &dst->u.get.ubuf,
1526                                                       0, ELF_GR_OFFSET(1));
1527                 if (dst->ret || dst->count == 0)
1528                         return;
1529         }
1530
1531         /* gr1 - gr15 */
1532         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1533                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1534                 min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
1535                          (dst->pos + dst->count) : ELF_GR_OFFSET(16);
1536                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1537                                 index++)
1538                         if (access_elf_reg(dst->target, info, i,
1539                                                 &tmp[index], 0) < 0) {
1540                                 dst->ret = -EIO;
1541                                 return;
1542                         }
1543                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1544                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1545                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1546                 if (dst->ret || dst->count == 0)
1547                         return;
1548         }
1549
1550         /* r16-r31 */
1551         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1552                 pt = task_pt_regs(dst->target);
1553                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1554                                 &dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
1555                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1556                 if (dst->ret || dst->count == 0)
1557                         return;
1558         }
1559
1560         /* nat, pr, b0 - b7 */
1561         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1562                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1563                 min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
1564                          (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
1565                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1566                                 index++)
1567                         if (access_elf_reg(dst->target, info, i,
1568                                                 &tmp[index], 0) < 0) {
1569                                 dst->ret = -EIO;
1570                                 return;
1571                         }
1572                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1573                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1574                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1575                 if (dst->ret || dst->count == 0)
1576                         return;
1577         }
1578
1579         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1580          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1581          */
1582         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1583                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1584                 min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
1585                          (dst->pos + dst->count) : ELF_AR_END_OFFSET;
1586                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1587                                 index++)
1588                         if (access_elf_reg(dst->target, info, i,
1589                                                 &tmp[index], 0) < 0) {
1590                                 dst->ret = -EIO;
1591                                 return;
1592                         }
1593                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1594                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1595                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1596         }
1597 }
1598
1599 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1600 {
1601         struct pt_regs *pt;
1602         struct regset_getset *dst = arg;
1603         elf_greg_t tmp[16];
1604         unsigned int i, index;
1605
1606         if (unw_unwind_to_user(info) < 0)
1607                 return;
1608
1609         /* Skip r0 */
1610         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1611                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1612                                                        &dst->u.set.kbuf,
1613                                                        &dst->u.set.ubuf,
1614                                                        0, ELF_GR_OFFSET(1));
1615                 if (dst->ret || dst->count == 0)
1616                         return;
1617         }
1618
1619         /* gr1-gr15 */
1620         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1621                 i = dst->pos;
1622                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1623                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1624                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1625                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1626                 if (dst->ret)
1627                         return;
1628                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1629                         if (access_elf_reg(dst->target, info, i,
1630                                                 &tmp[index], 1) < 0) {
1631                                 dst->ret = -EIO;
1632                                 return;
1633                         }
1634                 if (dst->count == 0)
1635                         return;
1636         }
1637
1638         /* gr16-gr31 */
1639         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1640                 pt = task_pt_regs(dst->target);
1641                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1642                                 &dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
1643                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1644                 if (dst->ret || dst->count == 0)
1645                         return;
1646         }
1647
1648         /* nat, pr, b0 - b7 */
1649         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1650                 i = dst->pos;
1651                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1652                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1653                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1654                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1655                 if (dst->ret)
1656                         return;
1657                 for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
1658                         if (access_elf_reg(dst->target, info, i,
1659                                                 &tmp[index], 1) < 0) {
1660                                 dst->ret = -EIO;
1661                                 return;
1662                         }
1663                 if (dst->count == 0)
1664                         return;
1665         }
1666
1667         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1668          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1669          */
1670         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1671                 i = dst->pos;
1672                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1673                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1674                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1675                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1676                 if (dst->ret)
1677                         return;
1678                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1679                         if (access_elf_reg(dst->target, info, i,
1680                                                 &tmp[index], 1) < 0) {
1681                                 dst->ret = -EIO;
1682                                 return;
1683                         }
1684         }
1685 }
1686
1687 #define ELF_FP_OFFSET(i)        (i * sizeof(elf_fpreg_t))
1688
1689 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1690 {
1691         struct regset_getset *dst = arg;
1692         struct task_struct *task = dst->target;
1693         elf_fpreg_t tmp[30];
1694         int index, min_copy, i;
1695
1696         if (unw_unwind_to_user(info) < 0)
1697                 return;
1698
1699         /* Skip pos 0 and 1 */
1700         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1701                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1702                                                       &dst->u.get.kbuf,
1703                                                       &dst->u.get.ubuf,
1704                                                       0, ELF_FP_OFFSET(2));
1705                 if (dst->count == 0 || dst->ret)
1706                         return;
1707         }
1708
1709         /* fr2-fr31 */
1710         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1711                 index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t);
1712
1713                 min_copy = min(((unsigned int)ELF_FP_OFFSET(32)),
1714                                 dst->pos + dst->count);
1715                 for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t),
1716                                 index++)
1717                         if (unw_get_fr(info, i / sizeof(elf_fpreg_t),
1718                                          &tmp[index])) {
1719                                 dst->ret = -EIO;
1720                                 return;
1721                         }
1722                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1723                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1724                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1725                 if (dst->count == 0 || dst->ret)
1726                         return;
1727         }
1728
1729         /* fph */
1730         if (dst->count > 0) {
1731                 ia64_flush_fph(dst->target);
1732                 if (task->thread.flags & IA64_THREAD_FPH_VALID)
1733                         dst->ret = user_regset_copyout(
1734                                 &dst->pos, &dst->count,
1735                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1736                                 &dst->target->thread.fph,
1737                                 ELF_FP_OFFSET(32), -1);
1738                 else
1739                         /* Zero fill instead.  */
1740                         dst->ret = user_regset_copyout_zero(
1741                                 &dst->pos, &dst->count,
1742                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1743                                 ELF_FP_OFFSET(32), -1);
1744         }
1745 }
1746
1747 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1748 {
1749         struct regset_getset *dst = arg;
1750         elf_fpreg_t fpreg, tmp[30];
1751         int index, start, end;
1752
1753         if (unw_unwind_to_user(info) < 0)
1754                 return;
1755
1756         /* Skip pos 0 and 1 */
1757         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1758                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1759                                                        &dst->u.set.kbuf,
1760                                                        &dst->u.set.ubuf,
1761                                                        0, ELF_FP_OFFSET(2));
1762                 if (dst->count == 0 || dst->ret)
1763                         return;
1764         }
1765
1766         /* fr2-fr31 */
1767         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1768                 start = dst->pos;
1769                 end = min(((unsigned int)ELF_FP_OFFSET(32)),
1770                          dst->pos + dst->count);
1771                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1772                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1773                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1774                 if (dst->ret)
1775                         return;
1776
1777                 if (start & 0xF) { /* only write high part */
1778                         if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1779                                          &fpreg)) {
1780                                 dst->ret = -EIO;
1781                                 return;
1782                         }
1783                         tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1784                                 = fpreg.u.bits[0];
1785                         start &= ~0xFUL;
1786                 }
1787                 if (end & 0xF) { /* only write low part */
1788                         if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1789                                         &fpreg)) {
1790                                 dst->ret = -EIO;
1791                                 return;
1792                         }
1793                         tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1794                                 = fpreg.u.bits[1];
1795                         end = (end + 0xF) & ~0xFUL;
1796                 }
1797
1798                 for ( ; start < end ; start += sizeof(elf_fpreg_t)) {
1799                         index = start / sizeof(elf_fpreg_t);
1800                         if (unw_set_fr(info, index, tmp[index - 2])) {
1801                                 dst->ret = -EIO;
1802                                 return;
1803                         }
1804                 }
1805                 if (dst->ret || dst->count == 0)
1806                         return;
1807         }
1808
1809         /* fph */
1810         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1811                 ia64_sync_fph(dst->target);
1812                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1813                                                 &dst->u.set.kbuf,
1814                                                 &dst->u.set.ubuf,
1815                                                 &dst->target->thread.fph,
1816                                                 ELF_FP_OFFSET(32), -1);
1817         }
1818 }
1819
1820 static int
1821 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1822                struct task_struct *target,
1823                const struct user_regset *regset,
1824                unsigned int pos, unsigned int count,
1825                const void *kbuf, const void __user *ubuf)
1826 {
1827         struct regset_getset info = { .target = target, .regset = regset,
1828                                  .pos = pos, .count = count,
1829                                  .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1830                                  .ret = 0 };
1831
1832         if (target == current)
1833                 unw_init_running(call, &info);
1834         else {
1835                 struct unw_frame_info ufi;
1836                 memset(&ufi, 0, sizeof(ufi));
1837                 unw_init_from_blocked_task(&ufi, target);
1838                 (*call)(&ufi, &info);
1839         }
1840
1841         return info.ret;
1842 }
1843
1844 static int
1845 gpregs_get(struct task_struct *target,
1846            const struct user_regset *regset,
1847            unsigned int pos, unsigned int count,
1848            void *kbuf, void __user *ubuf)
1849 {
1850         return do_regset_call(do_gpregs_get, target, regset, pos, count,
1851                 kbuf, ubuf);
1852 }
1853
1854 static int gpregs_set(struct task_struct *target,
1855                 const struct user_regset *regset,
1856                 unsigned int pos, unsigned int count,
1857                 const void *kbuf, const void __user *ubuf)
1858 {
1859         return do_regset_call(do_gpregs_set, target, regset, pos, count,
1860                 kbuf, ubuf);
1861 }
1862
1863 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1864 {
1865         do_sync_rbs(info, ia64_sync_user_rbs);
1866 }
1867
1868 /*
1869  * This is called to write back the register backing store.
1870  * ptrace does this before it stops, so that a tracer reading the user
1871  * memory after the thread stops will get the current register data.
1872  */
1873 static int
1874 gpregs_writeback(struct task_struct *target,
1875                  const struct user_regset *regset,
1876                  int now)
1877 {
1878         if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1879                 return 0;
1880         set_notify_resume(target);
1881         return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1882                 NULL, NULL);
1883 }
1884
1885 static int
1886 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1887 {
1888         return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1889 }
1890
1891 static int fpregs_get(struct task_struct *target,
1892                 const struct user_regset *regset,
1893                 unsigned int pos, unsigned int count,
1894                 void *kbuf, void __user *ubuf)
1895 {
1896         return do_regset_call(do_fpregs_get, target, regset, pos, count,
1897                 kbuf, ubuf);
1898 }
1899
1900 static int fpregs_set(struct task_struct *target,
1901                 const struct user_regset *regset,
1902                 unsigned int pos, unsigned int count,
1903                 const void *kbuf, const void __user *ubuf)
1904 {
1905         return do_regset_call(do_fpregs_set, target, regset, pos, count,
1906                 kbuf, ubuf);
1907 }
1908
1909 static int
1910 access_uarea(struct task_struct *child, unsigned long addr,
1911               unsigned long *data, int write_access)
1912 {
1913         unsigned int pos = -1; /* an invalid value */
1914         int ret;
1915         unsigned long *ptr, regnum;
1916
1917         if ((addr & 0x7) != 0) {
1918                 dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1919                 return -1;
1920         }
1921         if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1922                 (addr >= PT_R7 + 8 && addr < PT_B1) ||
1923                 (addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1924                 (addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1925                 dprintk("ptrace: rejecting access to register "
1926                                         "address 0x%lx\n", addr);
1927                 return -1;
1928         }
1929
1930         switch (addr) {
1931         case PT_F32 ... (PT_F127 + 15):
1932                 pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1933                 break;
1934         case PT_F2 ... (PT_F5 + 15):
1935                 pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1936                 break;
1937         case PT_F10 ... (PT_F31 + 15):
1938                 pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1939                 break;
1940         case PT_F6 ... (PT_F9 + 15):
1941                 pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1942                 break;
1943         }
1944
1945         if (pos != -1) {
1946                 if (write_access)
1947                         ret = fpregs_set(child, NULL, pos,
1948                                 sizeof(unsigned long), data, NULL);
1949                 else
1950                         ret = fpregs_get(child, NULL, pos,
1951                                 sizeof(unsigned long), data, NULL);
1952                 if (ret != 0)
1953                         return -1;
1954                 return 0;
1955         }
1956
1957         switch (addr) {
1958         case PT_NAT_BITS:
1959                 pos = ELF_NAT_OFFSET;
1960                 break;
1961         case PT_R4 ... PT_R7:
1962                 pos = addr - PT_R4 + ELF_GR_OFFSET(4);
1963                 break;
1964         case PT_B1 ... PT_B5:
1965                 pos = addr - PT_B1 + ELF_BR_OFFSET(1);
1966                 break;
1967         case PT_AR_EC:
1968                 pos = ELF_AR_EC_OFFSET;
1969                 break;
1970         case PT_AR_LC:
1971                 pos = ELF_AR_LC_OFFSET;
1972                 break;
1973         case PT_CR_IPSR:
1974                 pos = ELF_CR_IPSR_OFFSET;
1975                 break;
1976         case PT_CR_IIP:
1977                 pos = ELF_CR_IIP_OFFSET;
1978                 break;
1979         case PT_CFM:
1980                 pos = ELF_CFM_OFFSET;
1981                 break;
1982         case PT_AR_UNAT:
1983                 pos = ELF_AR_UNAT_OFFSET;
1984                 break;
1985         case PT_AR_PFS:
1986                 pos = ELF_AR_PFS_OFFSET;
1987                 break;
1988         case PT_AR_RSC:
1989                 pos = ELF_AR_RSC_OFFSET;
1990                 break;
1991         case PT_AR_RNAT:
1992                 pos = ELF_AR_RNAT_OFFSET;
1993                 break;
1994         case PT_AR_BSPSTORE:
1995                 pos = ELF_AR_BSPSTORE_OFFSET;
1996                 break;
1997         case PT_PR:
1998                 pos = ELF_PR_OFFSET;
1999                 break;
2000         case PT_B6:
2001                 pos = ELF_BR_OFFSET(6);
2002                 break;
2003         case PT_AR_BSP:
2004                 pos = ELF_AR_BSP_OFFSET;
2005                 break;
2006         case PT_R1 ... PT_R3:
2007                 pos = addr - PT_R1 + ELF_GR_OFFSET(1);
2008                 break;
2009         case PT_R12 ... PT_R15:
2010                 pos = addr - PT_R12 + ELF_GR_OFFSET(12);
2011                 break;
2012         case PT_R8 ... PT_R11:
2013                 pos = addr - PT_R8 + ELF_GR_OFFSET(8);
2014                 break;
2015         case PT_R16 ... PT_R31:
2016                 pos = addr - PT_R16 + ELF_GR_OFFSET(16);
2017                 break;
2018         case PT_AR_CCV:
2019                 pos = ELF_AR_CCV_OFFSET;
2020                 break;
2021         case PT_AR_FPSR:
2022                 pos = ELF_AR_FPSR_OFFSET;
2023                 break;
2024         case PT_B0:
2025                 pos = ELF_BR_OFFSET(0);
2026                 break;
2027         case PT_B7:
2028                 pos = ELF_BR_OFFSET(7);
2029                 break;
2030         case PT_AR_CSD:
2031                 pos = ELF_AR_CSD_OFFSET;
2032                 break;
2033         case PT_AR_SSD:
2034                 pos = ELF_AR_SSD_OFFSET;
2035                 break;
2036         }
2037
2038         if (pos != -1) {
2039                 if (write_access)
2040                         ret = gpregs_set(child, NULL, pos,
2041                                 sizeof(unsigned long), data, NULL);
2042                 else
2043                         ret = gpregs_get(child, NULL, pos,
2044                                 sizeof(unsigned long), data, NULL);
2045                 if (ret != 0)
2046                         return -1;
2047                 return 0;
2048         }
2049
2050         /* access debug registers */
2051         if (addr >= PT_IBR) {
2052                 regnum = (addr - PT_IBR) >> 3;
2053                 ptr = &child->thread.ibr[0];
2054         } else {
2055                 regnum = (addr - PT_DBR) >> 3;
2056                 ptr = &child->thread.dbr[0];
2057         }
2058
2059         if (regnum >= 8) {
2060                 dprintk("ptrace: rejecting access to register "
2061                                 "address 0x%lx\n", addr);
2062                 return -1;
2063         }
2064 #ifdef CONFIG_PERFMON
2065         /*
2066          * Check if debug registers are used by perfmon. This
2067          * test must be done once we know that we can do the
2068          * operation, i.e. the arguments are all valid, but
2069          * before we start modifying the state.
2070          *
2071          * Perfmon needs to keep a count of how many processes
2072          * are trying to modify the debug registers for system
2073          * wide monitoring sessions.
2074          *
2075          * We also include read access here, because they may
2076          * cause the PMU-installed debug register state
2077          * (dbr[], ibr[]) to be reset. The two arrays are also
2078          * used by perfmon, but we do not use
2079          * IA64_THREAD_DBG_VALID. The registers are restored
2080          * by the PMU context switch code.
2081          */
2082         if (pfm_use_debug_registers(child))
2083                 return -1;
2084 #endif
2085
2086         if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
2087                 child->thread.flags |= IA64_THREAD_DBG_VALID;
2088                 memset(child->thread.dbr, 0,
2089                                 sizeof(child->thread.dbr));
2090                 memset(child->thread.ibr, 0,
2091                                 sizeof(child->thread.ibr));
2092         }
2093
2094         ptr += regnum;
2095
2096         if ((regnum & 1) && write_access) {
2097                 /* don't let the user set kernel-level breakpoints: */
2098                 *ptr = *data & ~(7UL << 56);
2099                 return 0;
2100         }
2101         if (write_access)
2102                 *ptr = *data;
2103         else
2104                 *data = *ptr;
2105         return 0;
2106 }
2107
2108 static const struct user_regset native_regsets[] = {
2109         {
2110                 .core_note_type = NT_PRSTATUS,
2111                 .n = ELF_NGREG,
2112                 .size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2113                 .get = gpregs_get, .set = gpregs_set,
2114                 .writeback = gpregs_writeback
2115         },
2116         {
2117                 .core_note_type = NT_PRFPREG,
2118                 .n = ELF_NFPREG,
2119                 .size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2120                 .get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2121         },
2122 };
2123
2124 static const struct user_regset_view user_ia64_view = {
2125         .name = "ia64",
2126         .e_machine = EM_IA_64,
2127         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2128 };
2129
2130 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2131 {
2132         return &user_ia64_view;
2133 }
2134
2135 struct syscall_get_set_args {
2136         unsigned int i;
2137         unsigned int n;
2138         unsigned long *args;
2139         struct pt_regs *regs;
2140         int rw;
2141 };
2142
2143 static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2144 {
2145         struct syscall_get_set_args *args = data;
2146         struct pt_regs *pt = args->regs;
2147         unsigned long *krbs, cfm, ndirty;
2148         int i, count;
2149
2150         if (unw_unwind_to_user(info) < 0)
2151                 return;
2152
2153         cfm = pt->cr_ifs;
2154         krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2155         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2156
2157         count = 0;
2158         if (in_syscall(pt))
2159                 count = min_t(int, args->n, cfm & 0x7f);
2160
2161         for (i = 0; i < count; i++) {
2162                 if (args->rw)
2163                         *ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
2164                                 args->args[i];
2165                 else
2166                         args->args[i] = *ia64_rse_skip_regs(krbs,
2167                                 ndirty + i + args->i);
2168         }
2169
2170         if (!args->rw) {
2171                 while (i < args->n) {
2172                         args->args[i] = 0;
2173                         i++;
2174                 }
2175         }
2176 }
2177
2178 void ia64_syscall_get_set_arguments(struct task_struct *task,
2179         struct pt_regs *regs, unsigned int i, unsigned int n,
2180         unsigned long *args, int rw)
2181 {
2182         struct syscall_get_set_args data = {
2183                 .i = i,
2184                 .n = n,
2185                 .args = args,
2186                 .regs = regs,
2187                 .rw = rw,
2188         };
2189
2190         if (task == current)
2191                 unw_init_running(syscall_get_set_args_cb, &data);
2192         else {
2193                 struct unw_frame_info ufi;
2194                 memset(&ufi, 0, sizeof(ufi));
2195                 unw_init_from_blocked_task(&ufi, task);
2196                 syscall_get_set_args_cb(&ufi, &data);
2197         }
2198 }