arch/ia64/kernel/ptrace.c

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This source file includes following definitions.
in_syscall
ia64_get_scratch_nat_bits
ia64_put_scratch_nat_bits
ia64_increment_ip
ia64_decrement_ip
get_rnat
put_rnat
on_kernel_rbs
ia64_peek
ia64_poke
ia64_get_user_rbs_end
ia64_sync_user_rbs
ia64_sync_kernel_rbs
do_sync_rbs
ia64_ptrace_stop
ia64_sync_krbs
ptrace_attach_sync_user_rbs
ia64_flush_fph
ia64_sync_fph
convert_to_non_syscall
access_nat_bits
ptrace_getregs
ptrace_setregs
user_enable_single_step
user_enable_block_step
user_disable_single_step
ptrace_disable
arch_ptrace
syscall_trace_enter
syscall_trace_leave
access_elf_gpreg
access_elf_breg
access_elf_areg
access_elf_reg
do_gpregs_get
do_gpregs_set
do_fpregs_get
do_fpregs_set
do_regset_call
gpregs_get
gpregs_set
do_gpregs_writeback
gpregs_writeback
fpregs_active
fpregs_get
fpregs_set
access_uarea
task_user_regset_view
syscall_get_set_args_cb
ia64_syscall_get_set_arguments
   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Kernel support for the ptrace() and syscall tracing interfaces.
   4  *
   5  * Copyright (C) 1999-2005 Hewlett-Packard Co
   6  *      David Mosberger-Tang <davidm@hpl.hp.com>
   7  * Copyright (C) 2006 Intel Co
   8  *  2006-08-12  - IA64 Native Utrace implementation support added by
   9  *      Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
  10  *
  11  * Derived from the x86 and Alpha versions.
  12  */
  13 #include <linux/kernel.h>
  14 #include <linux/sched.h>
  15 #include <linux/sched/task.h>
  16 #include <linux/sched/task_stack.h>
  17 #include <linux/mm.h>
  18 #include <linux/errno.h>
  19 #include <linux/ptrace.h>
  20 #include <linux/user.h>
  21 #include <linux/security.h>
  22 #include <linux/audit.h>
  23 #include <linux/signal.h>
  24 #include <linux/regset.h>
  25 #include <linux/elf.h>
  26 #include <linux/tracehook.h>
  27 
  28 #include <asm/pgtable.h>
  29 #include <asm/processor.h>
  30 #include <asm/ptrace_offsets.h>
  31 #include <asm/rse.h>
  32 #include <linux/uaccess.h>
  33 #include <asm/unwind.h>
  34 #ifdef CONFIG_PERFMON
  35 #include <asm/perfmon.h>
  36 #endif
  37 
  38 #include "entry.h"
  39 
  40 /*
  41  * Bits in the PSR that we allow ptrace() to change:
  42  *      be, up, ac, mfl, mfh (the user mask; five bits total)
  43  *      db (debug breakpoint fault; one bit)
  44  *      id (instruction debug fault disable; one bit)
  45  *      dd (data debug fault disable; one bit)
  46  *      ri (restart instruction; two bits)
  47  *      is (instruction set; one bit)
  48  */
  49 #define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS      \
  50                    | IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
  51 
  52 #define MASK(nbits)     ((1UL << (nbits)) - 1)  /* mask with NBITS bits set */
  53 #define PFM_MASK        MASK(38)
  54 
  55 #define PTRACE_DEBUG    0
  56 
  57 #if PTRACE_DEBUG
  58 # define dprintk(format...)     printk(format)
  59 # define inline
  60 #else
  61 # define dprintk(format...)
  62 #endif
  63 
  64 /* Return TRUE if PT was created due to kernel-entry via a system-call.  */
  65 
  66 static inline int
  67 in_syscall (struct pt_regs *pt)
  68 {
  69         return (long) pt->cr_ifs >= 0;
  70 }
  71 
  72 /*
  73  * Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
  74  * bitset where bit i is set iff the NaT bit of register i is set.
  75  */
  76 unsigned long
  77 ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
  78 {
  79 #       define GET_BITS(first, last, unat)                              \
  80         ({                                                              \
  81                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
  82                 unsigned long nbits = (last - first + 1);               \
  83                 unsigned long mask = MASK(nbits) << first;              \
  84                 unsigned long dist;                                     \
  85                 if (bit < first)                                        \
  86                         dist = 64 + bit - first;                        \
  87                 else                                                    \
  88                         dist = bit - first;                             \
  89                 ia64_rotr(unat, dist) & mask;                           \
  90         })
  91         unsigned long val;
  92 
  93         /*
  94          * Registers that are stored consecutively in struct pt_regs
  95          * can be handled in parallel.  If the register order in
  96          * struct_pt_regs changes, this code MUST be updated.
  97          */
  98         val  = GET_BITS( 1,  1, scratch_unat);
  99         val |= GET_BITS( 2,  3, scratch_unat);
 100         val |= GET_BITS(12, 13, scratch_unat);
 101         val |= GET_BITS(14, 14, scratch_unat);
 102         val |= GET_BITS(15, 15, scratch_unat);
 103         val |= GET_BITS( 8, 11, scratch_unat);
 104         val |= GET_BITS(16, 31, scratch_unat);
 105         return val;
 106 
 107 #       undef GET_BITS
 108 }
 109 
 110 /*
 111  * Set the NaT bits for the scratch registers according to NAT and
 112  * return the resulting unat (assuming the scratch registers are
 113  * stored in PT).
 114  */
 115 unsigned long
 116 ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
 117 {
 118 #       define PUT_BITS(first, last, nat)                               \
 119         ({                                                              \
 120                 unsigned long bit = ia64_unat_pos(&pt->r##first);       \
 121                 unsigned long nbits = (last - first + 1);               \
 122                 unsigned long mask = MASK(nbits) << first;              \
 123                 long dist;                                              \
 124                 if (bit < first)                                        \
 125                         dist = 64 + bit - first;                        \
 126                 else                                                    \
 127                         dist = bit - first;                             \
 128                 ia64_rotl(nat & mask, dist);                            \
 129         })
 130         unsigned long scratch_unat;
 131 
 132         /*
 133          * Registers that are stored consecutively in struct pt_regs
 134          * can be handled in parallel.  If the register order in
 135          * struct_pt_regs changes, this code MUST be updated.
 136          */
 137         scratch_unat  = PUT_BITS( 1,  1, nat);
 138         scratch_unat |= PUT_BITS( 2,  3, nat);
 139         scratch_unat |= PUT_BITS(12, 13, nat);
 140         scratch_unat |= PUT_BITS(14, 14, nat);
 141         scratch_unat |= PUT_BITS(15, 15, nat);
 142         scratch_unat |= PUT_BITS( 8, 11, nat);
 143         scratch_unat |= PUT_BITS(16, 31, nat);
 144 
 145         return scratch_unat;
 146 
 147 #       undef PUT_BITS
 148 }
 149 
 150 #define IA64_MLX_TEMPLATE       0x2
 151 #define IA64_MOVL_OPCODE        6
 152 
 153 void
 154 ia64_increment_ip (struct pt_regs *regs)
 155 {
 156         unsigned long w0, ri = ia64_psr(regs)->ri + 1;
 157 
 158         if (ri > 2) {
 159                 ri = 0;
 160                 regs->cr_iip += 16;
 161         } else if (ri == 2) {
 162                 get_user(w0, (char __user *) regs->cr_iip + 0);
 163                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
 164                         /*
 165                          * rfi'ing to slot 2 of an MLX bundle causes
 166                          * an illegal operation fault.  We don't want
 167                          * that to happen...
 168                          */
 169                         ri = 0;
 170                         regs->cr_iip += 16;
 171                 }
 172         }
 173         ia64_psr(regs)->ri = ri;
 174 }
 175 
 176 void
 177 ia64_decrement_ip (struct pt_regs *regs)
 178 {
 179         unsigned long w0, ri = ia64_psr(regs)->ri - 1;
 180 
 181         if (ia64_psr(regs)->ri == 0) {
 182                 regs->cr_iip -= 16;
 183                 ri = 2;
 184                 get_user(w0, (char __user *) regs->cr_iip + 0);
 185                 if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
 186                         /*
 187                          * rfi'ing to slot 2 of an MLX bundle causes
 188                          * an illegal operation fault.  We don't want
 189                          * that to happen...
 190                          */
 191                         ri = 1;
 192                 }
 193         }
 194         ia64_psr(regs)->ri = ri;
 195 }
 196 
 197 /*
 198  * This routine is used to read an rnat bits that are stored on the
 199  * kernel backing store.  Since, in general, the alignment of the user
 200  * and kernel are different, this is not completely trivial.  In
 201  * essence, we need to construct the user RNAT based on up to two
 202  * kernel RNAT values and/or the RNAT value saved in the child's
 203  * pt_regs.
 204  *
 205  * user rbs
 206  *
 207  * +--------+ <-- lowest address
 208  * | slot62 |
 209  * +--------+
 210  * |  rnat  | 0x....1f8
 211  * +--------+
 212  * | slot00 | \
 213  * +--------+ |
 214  * | slot01 | > child_regs->ar_rnat
 215  * +--------+ |
 216  * | slot02 | /                         kernel rbs
 217  * +--------+                           +--------+
 218  *          <- child_regs->ar_bspstore  | slot61 | <-- krbs
 219  * +- - - - +                           +--------+
 220  *                                      | slot62 |
 221  * +- - - - +                           +--------+
 222  *                                      |  rnat  |
 223  * +- - - - +                           +--------+
 224  *   vrnat                              | slot00 |
 225  * +- - - - +                           +--------+
 226  *                                      =        =
 227  *                                      +--------+
 228  *                                      | slot00 | \
 229  *                                      +--------+ |
 230  *                                      | slot01 | > child_stack->ar_rnat
 231  *                                      +--------+ |
 232  *                                      | slot02 | /
 233  *                                      +--------+
 234  *                                                <--- child_stack->ar_bspstore
 235  *
 236  * The way to think of this code is as follows: bit 0 in the user rnat
 237  * corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
 238  * value.  The kernel rnat value holding this bit is stored in
 239  * variable rnat0.  rnat1 is loaded with the kernel rnat value that
 240  * form the upper bits of the user rnat value.
 241  *
 242  * Boundary cases:
 243  *
 244  * o when reading the rnat "below" the first rnat slot on the kernel
 245  *   backing store, rnat0/rnat1 are set to 0 and the low order bits are
 246  *   merged in from pt->ar_rnat.
 247  *
 248  * o when reading the rnat "above" the last rnat slot on the kernel
 249  *   backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
 250  */
 251 static unsigned long
 252 get_rnat (struct task_struct *task, struct switch_stack *sw,
 253           unsigned long *krbs, unsigned long *urnat_addr,
 254           unsigned long *urbs_end)
 255 {
 256         unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
 257         unsigned long umask = 0, mask, m;
 258         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
 259         long num_regs, nbits;
 260         struct pt_regs *pt;
 261 
 262         pt = task_pt_regs(task);
 263         kbsp = (unsigned long *) sw->ar_bspstore;
 264         ubspstore = (unsigned long *) pt->ar_bspstore;
 265 
 266         if (urbs_end < urnat_addr)
 267                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
 268         else
 269                 nbits = 63;
 270         mask = MASK(nbits);
 271         /*
 272          * First, figure out which bit number slot 0 in user-land maps
 273          * to in the kernel rnat.  Do this by figuring out how many
 274          * register slots we're beyond the user's backingstore and
 275          * then computing the equivalent address in kernel space.
 276          */
 277         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
 278         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
 279         shift = ia64_rse_slot_num(slot0_kaddr);
 280         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
 281         rnat0_kaddr = rnat1_kaddr - 64;
 282 
 283         if (ubspstore + 63 > urnat_addr) {
 284                 /* some bits need to be merged in from pt->ar_rnat */
 285                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
 286                 urnat = (pt->ar_rnat & umask);
 287                 mask &= ~umask;
 288                 if (!mask)
 289                         return urnat;
 290         }
 291 
 292         m = mask << shift;
 293         if (rnat0_kaddr >= kbsp)
 294                 rnat0 = sw->ar_rnat;
 295         else if (rnat0_kaddr > krbs)
 296                 rnat0 = *rnat0_kaddr;
 297         urnat |= (rnat0 & m) >> shift;
 298 
 299         m = mask >> (63 - shift);
 300         if (rnat1_kaddr >= kbsp)
 301                 rnat1 = sw->ar_rnat;
 302         else if (rnat1_kaddr > krbs)
 303                 rnat1 = *rnat1_kaddr;
 304         urnat |= (rnat1 & m) << (63 - shift);
 305         return urnat;
 306 }
 307 
 308 /*
 309  * The reverse of get_rnat.
 310  */
 311 static void
 312 put_rnat (struct task_struct *task, struct switch_stack *sw,
 313           unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
 314           unsigned long *urbs_end)
 315 {
 316         unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
 317         unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
 318         long num_regs, nbits;
 319         struct pt_regs *pt;
 320         unsigned long cfm, *urbs_kargs;
 321 
 322         pt = task_pt_regs(task);
 323         kbsp = (unsigned long *) sw->ar_bspstore;
 324         ubspstore = (unsigned long *) pt->ar_bspstore;
 325 
 326         urbs_kargs = urbs_end;
 327         if (in_syscall(pt)) {
 328                 /*
 329                  * If entered via syscall, don't allow user to set rnat bits
 330                  * for syscall args.
 331                  */
 332                 cfm = pt->cr_ifs;
 333                 urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
 334         }
 335 
 336         if (urbs_kargs >= urnat_addr)
 337                 nbits = 63;
 338         else {
 339                 if ((urnat_addr - 63) >= urbs_kargs)
 340                         return;
 341                 nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
 342         }
 343         mask = MASK(nbits);
 344 
 345         /*
 346          * First, figure out which bit number slot 0 in user-land maps
 347          * to in the kernel rnat.  Do this by figuring out how many
 348          * register slots we're beyond the user's backingstore and
 349          * then computing the equivalent address in kernel space.
 350          */
 351         num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
 352         slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
 353         shift = ia64_rse_slot_num(slot0_kaddr);
 354         rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
 355         rnat0_kaddr = rnat1_kaddr - 64;
 356 
 357         if (ubspstore + 63 > urnat_addr) {
 358                 /* some bits need to be place in pt->ar_rnat: */
 359                 umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
 360                 pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
 361                 mask &= ~umask;
 362                 if (!mask)
 363                         return;
 364         }
 365         /*
 366          * Note: Section 11.1 of the EAS guarantees that bit 63 of an
 367          * rnat slot is ignored. so we don't have to clear it here.
 368          */
 369         rnat0 = (urnat << shift);
 370         m = mask << shift;
 371         if (rnat0_kaddr >= kbsp)
 372                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
 373         else if (rnat0_kaddr > krbs)
 374                 *rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
 375 
 376         rnat1 = (urnat >> (63 - shift));
 377         m = mask >> (63 - shift);
 378         if (rnat1_kaddr >= kbsp)
 379                 sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
 380         else if (rnat1_kaddr > krbs)
 381                 *rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
 382 }
 383 
 384 static inline int
 385 on_kernel_rbs (unsigned long addr, unsigned long bspstore,
 386                unsigned long urbs_end)
 387 {
 388         unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
 389                                                       urbs_end);
 390         return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
 391 }
 392 
 393 /*
 394  * Read a word from the user-level backing store of task CHILD.  ADDR
 395  * is the user-level address to read the word from, VAL a pointer to
 396  * the return value, and USER_BSP gives the end of the user-level
 397  * backing store (i.e., it's the address that would be in ar.bsp after
 398  * the user executed a "cover" instruction).
 399  *
 400  * This routine takes care of accessing the kernel register backing
 401  * store for those registers that got spilled there.  It also takes
 402  * care of calculating the appropriate RNaT collection words.
 403  */
 404 long
 405 ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
 406            unsigned long user_rbs_end, unsigned long addr, long *val)
 407 {
 408         unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
 409         struct pt_regs *child_regs;
 410         size_t copied;
 411         long ret;
 412 
 413         urbs_end = (long *) user_rbs_end;
 414         laddr = (unsigned long *) addr;
 415         child_regs = task_pt_regs(child);
 416         bspstore = (unsigned long *) child_regs->ar_bspstore;
 417         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 418         if (on_kernel_rbs(addr, (unsigned long) bspstore,
 419                           (unsigned long) urbs_end))
 420         {
 421                 /*
 422                  * Attempt to read the RBS in an area that's actually
 423                  * on the kernel RBS => read the corresponding bits in
 424                  * the kernel RBS.
 425                  */
 426                 rnat_addr = ia64_rse_rnat_addr(laddr);
 427                 ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
 428 
 429                 if (laddr == rnat_addr) {
 430                         /* return NaT collection word itself */
 431                         *val = ret;
 432                         return 0;
 433                 }
 434 
 435                 if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
 436                         /*
 437                          * It is implementation dependent whether the
 438                          * data portion of a NaT value gets saved on a
 439                          * st8.spill or RSE spill (e.g., see EAS 2.6,
 440                          * 4.4.4.6 Register Spill and Fill).  To get
 441                          * consistent behavior across all possible
 442                          * IA-64 implementations, we return zero in
 443                          * this case.
 444                          */
 445                         *val = 0;
 446                         return 0;
 447                 }
 448 
 449                 if (laddr < urbs_end) {
 450                         /*
 451                          * The desired word is on the kernel RBS and
 452                          * is not a NaT.
 453                          */
 454                         regnum = ia64_rse_num_regs(bspstore, laddr);
 455                         *val = *ia64_rse_skip_regs(krbs, regnum);
 456                         return 0;
 457                 }
 458         }
 459         copied = access_process_vm(child, addr, &ret, sizeof(ret), FOLL_FORCE);
 460         if (copied != sizeof(ret))
 461                 return -EIO;
 462         *val = ret;
 463         return 0;
 464 }
 465 
 466 long
 467 ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
 468            unsigned long user_rbs_end, unsigned long addr, long val)
 469 {
 470         unsigned long *bspstore, *krbs, regnum, *laddr;
 471         unsigned long *urbs_end = (long *) user_rbs_end;
 472         struct pt_regs *child_regs;
 473 
 474         laddr = (unsigned long *) addr;
 475         child_regs = task_pt_regs(child);
 476         bspstore = (unsigned long *) child_regs->ar_bspstore;
 477         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 478         if (on_kernel_rbs(addr, (unsigned long) bspstore,
 479                           (unsigned long) urbs_end))
 480         {
 481                 /*
 482                  * Attempt to write the RBS in an area that's actually
 483                  * on the kernel RBS => write the corresponding bits
 484                  * in the kernel RBS.
 485                  */
 486                 if (ia64_rse_is_rnat_slot(laddr))
 487                         put_rnat(child, child_stack, krbs, laddr, val,
 488                                  urbs_end);
 489                 else {
 490                         if (laddr < urbs_end) {
 491                                 regnum = ia64_rse_num_regs(bspstore, laddr);
 492                                 *ia64_rse_skip_regs(krbs, regnum) = val;
 493                         }
 494                 }
 495         } else if (access_process_vm(child, addr, &val, sizeof(val),
 496                                 FOLL_FORCE | FOLL_WRITE)
 497                    != sizeof(val))
 498                 return -EIO;
 499         return 0;
 500 }
 501 
 502 /*
 503  * Calculate the address of the end of the user-level register backing
 504  * store.  This is the address that would have been stored in ar.bsp
 505  * if the user had executed a "cover" instruction right before
 506  * entering the kernel.  If CFMP is not NULL, it is used to return the
 507  * "current frame mask" that was active at the time the kernel was
 508  * entered.
 509  */
 510 unsigned long
 511 ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
 512                        unsigned long *cfmp)
 513 {
 514         unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
 515         long ndirty;
 516 
 517         krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
 518         bspstore = (unsigned long *) pt->ar_bspstore;
 519         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
 520 
 521         if (in_syscall(pt))
 522                 ndirty += (cfm & 0x7f);
 523         else
 524                 cfm &= ~(1UL << 63);    /* clear valid bit */
 525 
 526         if (cfmp)
 527                 *cfmp = cfm;
 528         return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
 529 }
 530 
 531 /*
 532  * Synchronize (i.e, write) the RSE backing store living in kernel
 533  * space to the VM of the CHILD task.  SW and PT are the pointers to
 534  * the switch_stack and pt_regs structures, respectively.
 535  * USER_RBS_END is the user-level address at which the backing store
 536  * ends.
 537  */
 538 long
 539 ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
 540                     unsigned long user_rbs_start, unsigned long user_rbs_end)
 541 {
 542         unsigned long addr, val;
 543         long ret;
 544 
 545         /* now copy word for word from kernel rbs to user rbs: */
 546         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 547                 ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
 548                 if (ret < 0)
 549                         return ret;
 550                 if (access_process_vm(child, addr, &val, sizeof(val),
 551                                 FOLL_FORCE | FOLL_WRITE)
 552                     != sizeof(val))
 553                         return -EIO;
 554         }
 555         return 0;
 556 }
 557 
 558 static long
 559 ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
 560                 unsigned long user_rbs_start, unsigned long user_rbs_end)
 561 {
 562         unsigned long addr, val;
 563         long ret;
 564 
 565         /* now copy word for word from user rbs to kernel rbs: */
 566         for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
 567                 if (access_process_vm(child, addr, &val, sizeof(val),
 568                                 FOLL_FORCE)
 569                                 != sizeof(val))
 570                         return -EIO;
 571 
 572                 ret = ia64_poke(child, sw, user_rbs_end, addr, val);
 573                 if (ret < 0)
 574                         return ret;
 575         }
 576         return 0;
 577 }
 578 
 579 typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
 580                             unsigned long, unsigned long);
 581 
 582 static void do_sync_rbs(struct unw_frame_info *info, void *arg)
 583 {
 584         struct pt_regs *pt;
 585         unsigned long urbs_end;
 586         syncfunc_t fn = arg;
 587 
 588         if (unw_unwind_to_user(info) < 0)
 589                 return;
 590         pt = task_pt_regs(info->task);
 591         urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
 592 
 593         fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
 594 }
 595 
 596 /*
 597  * when a thread is stopped (ptraced), debugger might change thread's user
 598  * stack (change memory directly), and we must avoid the RSE stored in kernel
 599  * to override user stack (user space's RSE is newer than kernel's in the
 600  * case). To workaround the issue, we copy kernel RSE to user RSE before the
 601  * task is stopped, so user RSE has updated data.  we then copy user RSE to
 602  * kernel after the task is resummed from traced stop and kernel will use the
 603  * newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
 604  * synchronize user RSE to kernel.
 605  */
 606 void ia64_ptrace_stop(void)
 607 {
 608         if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
 609                 return;
 610         set_notify_resume(current);
 611         unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
 612 }
 613 
 614 /*
 615  * This is called to read back the register backing store.
 616  */
 617 void ia64_sync_krbs(void)
 618 {
 619         clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
 620 
 621         unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
 622 }
 623 
 624 /*
 625  * After PTRACE_ATTACH, a thread's register backing store area in user
 626  * space is assumed to contain correct data whenever the thread is
 627  * stopped.  arch_ptrace_stop takes care of this on tracing stops.
 628  * But if the child was already stopped for job control when we attach
 629  * to it, then it might not ever get into ptrace_stop by the time we
 630  * want to examine the user memory containing the RBS.
 631  */
 632 void
 633 ptrace_attach_sync_user_rbs (struct task_struct *child)
 634 {
 635         int stopped = 0;
 636         struct unw_frame_info info;
 637 
 638         /*
 639          * If the child is in TASK_STOPPED, we need to change that to
 640          * TASK_TRACED momentarily while we operate on it.  This ensures
 641          * that the child won't be woken up and return to user mode while
 642          * we are doing the sync.  (It can only be woken up for SIGKILL.)
 643          */
 644 
 645         read_lock(&tasklist_lock);
 646         if (child->sighand) {
 647                 spin_lock_irq(&child->sighand->siglock);
 648                 if (child->state == TASK_STOPPED &&
 649                     !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
 650                         set_notify_resume(child);
 651 
 652                         child->state = TASK_TRACED;
 653                         stopped = 1;
 654                 }
 655                 spin_unlock_irq(&child->sighand->siglock);
 656         }
 657         read_unlock(&tasklist_lock);
 658 
 659         if (!stopped)
 660                 return;
 661 
 662         unw_init_from_blocked_task(&info, child);
 663         do_sync_rbs(&info, ia64_sync_user_rbs);
 664 
 665         /*
 666          * Now move the child back into TASK_STOPPED if it should be in a
 667          * job control stop, so that SIGCONT can be used to wake it up.
 668          */
 669         read_lock(&tasklist_lock);
 670         if (child->sighand) {
 671                 spin_lock_irq(&child->sighand->siglock);
 672                 if (child->state == TASK_TRACED &&
 673                     (child->signal->flags & SIGNAL_STOP_STOPPED)) {
 674                         child->state = TASK_STOPPED;
 675                 }
 676                 spin_unlock_irq(&child->sighand->siglock);
 677         }
 678         read_unlock(&tasklist_lock);
 679 }
 680 
 681 /*
 682  * Write f32-f127 back to task->thread.fph if it has been modified.
 683  */
 684 inline void
 685 ia64_flush_fph (struct task_struct *task)
 686 {
 687         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 688 
 689         /*
 690          * Prevent migrating this task while
 691          * we're fiddling with the FPU state
 692          */
 693         preempt_disable();
 694         if (ia64_is_local_fpu_owner(task) && psr->mfh) {
 695                 psr->mfh = 0;
 696                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 697                 ia64_save_fpu(&task->thread.fph[0]);
 698         }
 699         preempt_enable();
 700 }
 701 
 702 /*
 703  * Sync the fph state of the task so that it can be manipulated
 704  * through thread.fph.  If necessary, f32-f127 are written back to
 705  * thread.fph or, if the fph state hasn't been used before, thread.fph
 706  * is cleared to zeroes.  Also, access to f32-f127 is disabled to
 707  * ensure that the task picks up the state from thread.fph when it
 708  * executes again.
 709  */
 710 void
 711 ia64_sync_fph (struct task_struct *task)
 712 {
 713         struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
 714 
 715         ia64_flush_fph(task);
 716         if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
 717                 task->thread.flags |= IA64_THREAD_FPH_VALID;
 718                 memset(&task->thread.fph, 0, sizeof(task->thread.fph));
 719         }
 720         ia64_drop_fpu(task);
 721         psr->dfh = 1;
 722 }
 723 
 724 /*
 725  * Change the machine-state of CHILD such that it will return via the normal
 726  * kernel exit-path, rather than the syscall-exit path.
 727  */
 728 static void
 729 convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
 730                         unsigned long cfm)
 731 {
 732         struct unw_frame_info info, prev_info;
 733         unsigned long ip, sp, pr;
 734 
 735         unw_init_from_blocked_task(&info, child);
 736         while (1) {
 737                 prev_info = info;
 738                 if (unw_unwind(&info) < 0)
 739                         return;
 740 
 741                 unw_get_sp(&info, &sp);
 742                 if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
 743                     < IA64_PT_REGS_SIZE) {
 744                         dprintk("ptrace.%s: ran off the top of the kernel "
 745                                 "stack\n", __func__);
 746                         return;
 747                 }
 748                 if (unw_get_pr (&prev_info, &pr) < 0) {
 749                         unw_get_rp(&prev_info, &ip);
 750                         dprintk("ptrace.%s: failed to read "
 751                                 "predicate register (ip=0x%lx)\n",
 752                                 __func__, ip);
 753                         return;
 754                 }
 755                 if (unw_is_intr_frame(&info)
 756                     && (pr & (1UL << PRED_USER_STACK)))
 757                         break;
 758         }
 759 
 760         /*
 761          * Note: at the time of this call, the target task is blocked
 762          * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
 763          * (aka, "pLvSys") we redirect execution from
 764          * .work_pending_syscall_end to .work_processed_kernel.
 765          */
 766         unw_get_pr(&prev_info, &pr);
 767         pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
 768         pr |=  (1UL << PRED_NON_SYSCALL);
 769         unw_set_pr(&prev_info, pr);
 770 
 771         pt->cr_ifs = (1UL << 63) | cfm;
 772         /*
 773          * Clear the memory that is NOT written on syscall-entry to
 774          * ensure we do not leak kernel-state to user when execution
 775          * resumes.
 776          */
 777         pt->r2 = 0;
 778         pt->r3 = 0;
 779         pt->r14 = 0;
 780         memset(&pt->r16, 0, 16*8);      /* clear r16-r31 */
 781         memset(&pt->f6, 0, 6*16);       /* clear f6-f11 */
 782         pt->b7 = 0;
 783         pt->ar_ccv = 0;
 784         pt->ar_csd = 0;
 785         pt->ar_ssd = 0;
 786 }
 787 
 788 static int
 789 access_nat_bits (struct task_struct *child, struct pt_regs *pt,
 790                  struct unw_frame_info *info,
 791                  unsigned long *data, int write_access)
 792 {
 793         unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
 794         char nat = 0;
 795 
 796         if (write_access) {
 797                 nat_bits = *data;
 798                 scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
 799                 if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
 800                         dprintk("ptrace: failed to set ar.unat\n");
 801                         return -1;
 802                 }
 803                 for (regnum = 4; regnum <= 7; ++regnum) {
 804                         unw_get_gr(info, regnum, &dummy, &nat);
 805                         unw_set_gr(info, regnum, dummy,
 806                                    (nat_bits >> regnum) & 1);
 807                 }
 808         } else {
 809                 if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
 810                         dprintk("ptrace: failed to read ar.unat\n");
 811                         return -1;
 812                 }
 813                 nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
 814                 for (regnum = 4; regnum <= 7; ++regnum) {
 815                         unw_get_gr(info, regnum, &dummy, &nat);
 816                         nat_bits |= (nat != 0) << regnum;
 817                 }
 818                 *data = nat_bits;
 819         }
 820         return 0;
 821 }
 822 
 823 static int
 824 access_uarea (struct task_struct *child, unsigned long addr,
 825               unsigned long *data, int write_access);
 826 
 827 static long
 828 ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 829 {
 830         unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
 831         struct unw_frame_info info;
 832         struct ia64_fpreg fpval;
 833         struct switch_stack *sw;
 834         struct pt_regs *pt;
 835         long ret, retval = 0;
 836         char nat = 0;
 837         int i;
 838 
 839         if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
 840                 return -EIO;
 841 
 842         pt = task_pt_regs(child);
 843         sw = (struct switch_stack *) (child->thread.ksp + 16);
 844         unw_init_from_blocked_task(&info, child);
 845         if (unw_unwind_to_user(&info) < 0) {
 846                 return -EIO;
 847         }
 848 
 849         if (((unsigned long) ppr & 0x7) != 0) {
 850                 dprintk("ptrace:unaligned register address %p\n", ppr);
 851                 return -EIO;
 852         }
 853 
 854         if (access_uarea(child, PT_CR_IPSR, &psr, 0) < 0
 855             || access_uarea(child, PT_AR_EC, &ec, 0) < 0
 856             || access_uarea(child, PT_AR_LC, &lc, 0) < 0
 857             || access_uarea(child, PT_AR_RNAT, &rnat, 0) < 0
 858             || access_uarea(child, PT_AR_BSP, &bsp, 0) < 0
 859             || access_uarea(child, PT_CFM, &cfm, 0)
 860             || access_uarea(child, PT_NAT_BITS, &nat_bits, 0))
 861                 return -EIO;
 862 
 863         /* control regs */
 864 
 865         retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
 866         retval |= __put_user(psr, &ppr->cr_ipsr);
 867 
 868         /* app regs */
 869 
 870         retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
 871         retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
 872         retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
 873         retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
 874         retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
 875         retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
 876 
 877         retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
 878         retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
 879         retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
 880         retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
 881         retval |= __put_user(cfm, &ppr->cfm);
 882 
 883         /* gr1-gr3 */
 884 
 885         retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
 886         retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
 887 
 888         /* gr4-gr7 */
 889 
 890         for (i = 4; i < 8; i++) {
 891                 if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
 892                         return -EIO;
 893                 retval |= __put_user(val, &ppr->gr[i]);
 894         }
 895 
 896         /* gr8-gr11 */
 897 
 898         retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
 899 
 900         /* gr12-gr15 */
 901 
 902         retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
 903         retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
 904         retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
 905 
 906         /* gr16-gr31 */
 907 
 908         retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
 909 
 910         /* b0 */
 911 
 912         retval |= __put_user(pt->b0, &ppr->br[0]);
 913 
 914         /* b1-b5 */
 915 
 916         for (i = 1; i < 6; i++) {
 917                 if (unw_access_br(&info, i, &val, 0) < 0)
 918                         return -EIO;
 919                 __put_user(val, &ppr->br[i]);
 920         }
 921 
 922         /* b6-b7 */
 923 
 924         retval |= __put_user(pt->b6, &ppr->br[6]);
 925         retval |= __put_user(pt->b7, &ppr->br[7]);
 926 
 927         /* fr2-fr5 */
 928 
 929         for (i = 2; i < 6; i++) {
 930                 if (unw_get_fr(&info, i, &fpval) < 0)
 931                         return -EIO;
 932                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 933         }
 934 
 935         /* fr6-fr11 */
 936 
 937         retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
 938                                  sizeof(struct ia64_fpreg) * 6);
 939 
 940         /* fp scratch regs(12-15) */
 941 
 942         retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
 943                                  sizeof(struct ia64_fpreg) * 4);
 944 
 945         /* fr16-fr31 */
 946 
 947         for (i = 16; i < 32; i++) {
 948                 if (unw_get_fr(&info, i, &fpval) < 0)
 949                         return -EIO;
 950                 retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
 951         }
 952 
 953         /* fph */
 954 
 955         ia64_flush_fph(child);
 956         retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
 957                                  sizeof(ppr->fr[32]) * 96);
 958 
 959         /*  preds */
 960 
 961         retval |= __put_user(pt->pr, &ppr->pr);
 962 
 963         /* nat bits */
 964 
 965         retval |= __put_user(nat_bits, &ppr->nat);
 966 
 967         ret = retval ? -EIO : 0;
 968         return ret;
 969 }
 970 
 971 static long
 972 ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
 973 {
 974         unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
 975         struct unw_frame_info info;
 976         struct switch_stack *sw;
 977         struct ia64_fpreg fpval;
 978         struct pt_regs *pt;
 979         long ret, retval = 0;
 980         int i;
 981 
 982         memset(&fpval, 0, sizeof(fpval));
 983 
 984         if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
 985                 return -EIO;
 986 
 987         pt = task_pt_regs(child);
 988         sw = (struct switch_stack *) (child->thread.ksp + 16);
 989         unw_init_from_blocked_task(&info, child);
 990         if (unw_unwind_to_user(&info) < 0) {
 991                 return -EIO;
 992         }
 993 
 994         if (((unsigned long) ppr & 0x7) != 0) {
 995                 dprintk("ptrace:unaligned register address %p\n", ppr);
 996                 return -EIO;
 997         }
 998 
 999         /* control regs */
1000 
1001         retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
1002         retval |= __get_user(psr, &ppr->cr_ipsr);
1003 
1004         /* app regs */
1005 
1006         retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
1007         retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
1008         retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
1009         retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
1010         retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
1011         retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
1012 
1013         retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
1014         retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
1015         retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
1016         retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
1017         retval |= __get_user(cfm, &ppr->cfm);
1018 
1019         /* gr1-gr3 */
1020 
1021         retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
1022         retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
1023 
1024         /* gr4-gr7 */
1025 
1026         for (i = 4; i < 8; i++) {
1027                 retval |= __get_user(val, &ppr->gr[i]);
1028                 /* NaT bit will be set via PT_NAT_BITS: */
1029                 if (unw_set_gr(&info, i, val, 0) < 0)
1030                         return -EIO;
1031         }
1032 
1033         /* gr8-gr11 */
1034 
1035         retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
1036 
1037         /* gr12-gr15 */
1038 
1039         retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
1040         retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
1041         retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
1042 
1043         /* gr16-gr31 */
1044 
1045         retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
1046 
1047         /* b0 */
1048 
1049         retval |= __get_user(pt->b0, &ppr->br[0]);
1050 
1051         /* b1-b5 */
1052 
1053         for (i = 1; i < 6; i++) {
1054                 retval |= __get_user(val, &ppr->br[i]);
1055                 unw_set_br(&info, i, val);
1056         }
1057 
1058         /* b6-b7 */
1059 
1060         retval |= __get_user(pt->b6, &ppr->br[6]);
1061         retval |= __get_user(pt->b7, &ppr->br[7]);
1062 
1063         /* fr2-fr5 */
1064 
1065         for (i = 2; i < 6; i++) {
1066                 retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
1067                 if (unw_set_fr(&info, i, fpval) < 0)
1068                         return -EIO;
1069         }
1070 
1071         /* fr6-fr11 */
1072 
1073         retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
1074                                    sizeof(ppr->fr[6]) * 6);
1075 
1076         /* fp scratch regs(12-15) */
1077 
1078         retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
1079                                    sizeof(ppr->fr[12]) * 4);
1080 
1081         /* fr16-fr31 */
1082 
1083         for (i = 16; i < 32; i++) {
1084                 retval |= __copy_from_user(&fpval, &ppr->fr[i],
1085                                            sizeof(fpval));
1086                 if (unw_set_fr(&info, i, fpval) < 0)
1087                         return -EIO;
1088         }
1089 
1090         /* fph */
1091 
1092         ia64_sync_fph(child);
1093         retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
1094                                    sizeof(ppr->fr[32]) * 96);
1095 
1096         /* preds */
1097 
1098         retval |= __get_user(pt->pr, &ppr->pr);
1099 
1100         /* nat bits */
1101 
1102         retval |= __get_user(nat_bits, &ppr->nat);
1103 
1104         retval |= access_uarea(child, PT_CR_IPSR, &psr, 1);
1105         retval |= access_uarea(child, PT_AR_RSC, &rsc, 1);
1106         retval |= access_uarea(child, PT_AR_EC, &ec, 1);
1107         retval |= access_uarea(child, PT_AR_LC, &lc, 1);
1108         retval |= access_uarea(child, PT_AR_RNAT, &rnat, 1);
1109         retval |= access_uarea(child, PT_AR_BSP, &bsp, 1);
1110         retval |= access_uarea(child, PT_CFM, &cfm, 1);
1111         retval |= access_uarea(child, PT_NAT_BITS, &nat_bits, 1);
1112 
1113         ret = retval ? -EIO : 0;
1114         return ret;
1115 }
1116 
1117 void
1118 user_enable_single_step (struct task_struct *child)
1119 {
1120         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1121 
1122         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1123         child_psr->ss = 1;
1124 }
1125 
1126 void
1127 user_enable_block_step (struct task_struct *child)
1128 {
1129         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1130 
1131         set_tsk_thread_flag(child, TIF_SINGLESTEP);
1132         child_psr->tb = 1;
1133 }
1134 
1135 void
1136 user_disable_single_step (struct task_struct *child)
1137 {
1138         struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
1139 
1140         /* make sure the single step/taken-branch trap bits are not set: */
1141         clear_tsk_thread_flag(child, TIF_SINGLESTEP);
1142         child_psr->ss = 0;
1143         child_psr->tb = 0;
1144 }
1145 
1146 /*
1147  * Called by kernel/ptrace.c when detaching..
1148  *
1149  * Make sure the single step bit is not set.
1150  */
1151 void
1152 ptrace_disable (struct task_struct *child)
1153 {
1154         user_disable_single_step(child);
1155 }
1156 
1157 long
1158 arch_ptrace (struct task_struct *child, long request,
1159              unsigned long addr, unsigned long data)
1160 {
1161         switch (request) {
1162         case PTRACE_PEEKTEXT:
1163         case PTRACE_PEEKDATA:
1164                 /* read word at location addr */
1165                 if (ptrace_access_vm(child, addr, &data, sizeof(data),
1166                                 FOLL_FORCE)
1167                     != sizeof(data))
1168                         return -EIO;
1169                 /* ensure return value is not mistaken for error code */
1170                 force_successful_syscall_return();
1171                 return data;
1172 
1173         /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
1174          * by the generic ptrace_request().
1175          */
1176 
1177         case PTRACE_PEEKUSR:
1178                 /* read the word at addr in the USER area */
1179                 if (access_uarea(child, addr, &data, 0) < 0)
1180                         return -EIO;
1181                 /* ensure return value is not mistaken for error code */
1182                 force_successful_syscall_return();
1183                 return data;
1184 
1185         case PTRACE_POKEUSR:
1186                 /* write the word at addr in the USER area */
1187                 if (access_uarea(child, addr, &data, 1) < 0)
1188                         return -EIO;
1189                 return 0;
1190 
1191         case PTRACE_OLD_GETSIGINFO:
1192                 /* for backwards-compatibility */
1193                 return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
1194 
1195         case PTRACE_OLD_SETSIGINFO:
1196                 /* for backwards-compatibility */
1197                 return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
1198 
1199         case PTRACE_GETREGS:
1200                 return ptrace_getregs(child,
1201                                       (struct pt_all_user_regs __user *) data);
1202 
1203         case PTRACE_SETREGS:
1204                 return ptrace_setregs(child,
1205                                       (struct pt_all_user_regs __user *) data);
1206 
1207         default:
1208                 return ptrace_request(child, request, addr, data);
1209         }
1210 }
1211 
1212 
1213 /* "asmlinkage" so the input arguments are preserved... */
1214 
1215 asmlinkage long
1216 syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
1217                      long arg4, long arg5, long arg6, long arg7,
1218                      struct pt_regs regs)
1219 {
1220         if (test_thread_flag(TIF_SYSCALL_TRACE))
1221                 if (tracehook_report_syscall_entry(&regs))
1222                         return -ENOSYS;
1223 
1224         /* copy user rbs to kernel rbs */
1225         if (test_thread_flag(TIF_RESTORE_RSE))
1226                 ia64_sync_krbs();
1227 
1228 
1229         audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
1230 
1231         return 0;
1232 }
1233 
1234 /* "asmlinkage" so the input arguments are preserved... */
1235 
1236 asmlinkage void
1237 syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
1238                      long arg4, long arg5, long arg6, long arg7,
1239                      struct pt_regs regs)
1240 {
1241         int step;
1242 
1243         audit_syscall_exit(&regs);
1244 
1245         step = test_thread_flag(TIF_SINGLESTEP);
1246         if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1247                 tracehook_report_syscall_exit(&regs, step);
1248 
1249         /* copy user rbs to kernel rbs */
1250         if (test_thread_flag(TIF_RESTORE_RSE))
1251                 ia64_sync_krbs();
1252 }
1253 
1254 /* Utrace implementation starts here */
1255 struct regset_get {
1256         void *kbuf;
1257         void __user *ubuf;
1258 };
1259 
1260 struct regset_set {
1261         const void *kbuf;
1262         const void __user *ubuf;
1263 };
1264 
1265 struct regset_getset {
1266         struct task_struct *target;
1267         const struct user_regset *regset;
1268         union {
1269                 struct regset_get get;
1270                 struct regset_set set;
1271         } u;
1272         unsigned int pos;
1273         unsigned int count;
1274         int ret;
1275 };
1276 
1277 static int
1278 access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
1279                 unsigned long addr, unsigned long *data, int write_access)
1280 {
1281         struct pt_regs *pt;
1282         unsigned long *ptr = NULL;
1283         int ret;
1284         char nat = 0;
1285 
1286         pt = task_pt_regs(target);
1287         switch (addr) {
1288         case ELF_GR_OFFSET(1):
1289                 ptr = &pt->r1;
1290                 break;
1291         case ELF_GR_OFFSET(2):
1292         case ELF_GR_OFFSET(3):
1293                 ptr = (void *)&pt->r2 + (addr - ELF_GR_OFFSET(2));
1294                 break;
1295         case ELF_GR_OFFSET(4) ... ELF_GR_OFFSET(7):
1296                 if (write_access) {
1297                         /* read NaT bit first: */
1298                         unsigned long dummy;
1299 
1300                         ret = unw_get_gr(info, addr/8, &dummy, &nat);
1301                         if (ret < 0)
1302                                 return ret;
1303                 }
1304                 return unw_access_gr(info, addr/8, data, &nat, write_access);
1305         case ELF_GR_OFFSET(8) ... ELF_GR_OFFSET(11):
1306                 ptr = (void *)&pt->r8 + addr - ELF_GR_OFFSET(8);
1307                 break;
1308         case ELF_GR_OFFSET(12):
1309         case ELF_GR_OFFSET(13):
1310                 ptr = (void *)&pt->r12 + addr - ELF_GR_OFFSET(12);
1311                 break;
1312         case ELF_GR_OFFSET(14):
1313                 ptr = &pt->r14;
1314                 break;
1315         case ELF_GR_OFFSET(15):
1316                 ptr = &pt->r15;
1317         }
1318         if (write_access)
1319                 *ptr = *data;
1320         else
1321                 *data = *ptr;
1322         return 0;
1323 }
1324 
1325 static int
1326 access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
1327                 unsigned long addr, unsigned long *data, int write_access)
1328 {
1329         struct pt_regs *pt;
1330         unsigned long *ptr = NULL;
1331 
1332         pt = task_pt_regs(target);
1333         switch (addr) {
1334         case ELF_BR_OFFSET(0):
1335                 ptr = &pt->b0;
1336                 break;
1337         case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
1338                 return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
1339                                      data, write_access);
1340         case ELF_BR_OFFSET(6):
1341                 ptr = &pt->b6;
1342                 break;
1343         case ELF_BR_OFFSET(7):
1344                 ptr = &pt->b7;
1345         }
1346         if (write_access)
1347                 *ptr = *data;
1348         else
1349                 *data = *ptr;
1350         return 0;
1351 }
1352 
1353 static int
1354 access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
1355                 unsigned long addr, unsigned long *data, int write_access)
1356 {
1357         struct pt_regs *pt;
1358         unsigned long cfm, urbs_end;
1359         unsigned long *ptr = NULL;
1360 
1361         pt = task_pt_regs(target);
1362         if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
1363                 switch (addr) {
1364                 case ELF_AR_RSC_OFFSET:
1365                         /* force PL3 */
1366                         if (write_access)
1367                                 pt->ar_rsc = *data | (3 << 2);
1368                         else
1369                                 *data = pt->ar_rsc;
1370                         return 0;
1371                 case ELF_AR_BSP_OFFSET:
1372                         /*
1373                          * By convention, we use PT_AR_BSP to refer to
1374                          * the end of the user-level backing store.
1375                          * Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
1376                          * to get the real value of ar.bsp at the time
1377                          * the kernel was entered.
1378                          *
1379                          * Furthermore, when changing the contents of
1380                          * PT_AR_BSP (or PT_CFM) while the task is
1381                          * blocked in a system call, convert the state
1382                          * so that the non-system-call exit
1383                          * path is used.  This ensures that the proper
1384                          * state will be picked up when resuming
1385                          * execution.  However, it *also* means that
1386                          * once we write PT_AR_BSP/PT_CFM, it won't be
1387                          * possible to modify the syscall arguments of
1388                          * the pending system call any longer.  This
1389                          * shouldn't be an issue because modifying
1390                          * PT_AR_BSP/PT_CFM generally implies that
1391                          * we're either abandoning the pending system
1392                          * call or that we defer it's re-execution
1393                          * (e.g., due to GDB doing an inferior
1394                          * function call).
1395                          */
1396                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1397                         if (write_access) {
1398                                 if (*data != urbs_end) {
1399                                         if (in_syscall(pt))
1400                                                 convert_to_non_syscall(target,
1401                                                                        pt,
1402                                                                        cfm);
1403                                         /*
1404                                          * Simulate user-level write
1405                                          * of ar.bsp:
1406                                          */
1407                                         pt->loadrs = 0;
1408                                         pt->ar_bspstore = *data;
1409                                 }
1410                         } else
1411                                 *data = urbs_end;
1412                         return 0;
1413                 case ELF_AR_BSPSTORE_OFFSET:
1414                         ptr = &pt->ar_bspstore;
1415                         break;
1416                 case ELF_AR_RNAT_OFFSET:
1417                         ptr = &pt->ar_rnat;
1418                         break;
1419                 case ELF_AR_CCV_OFFSET:
1420                         ptr = &pt->ar_ccv;
1421                         break;
1422                 case ELF_AR_UNAT_OFFSET:
1423                         ptr = &pt->ar_unat;
1424                         break;
1425                 case ELF_AR_FPSR_OFFSET:
1426                         ptr = &pt->ar_fpsr;
1427                         break;
1428                 case ELF_AR_PFS_OFFSET:
1429                         ptr = &pt->ar_pfs;
1430                         break;
1431                 case ELF_AR_LC_OFFSET:
1432                         return unw_access_ar(info, UNW_AR_LC, data,
1433                                              write_access);
1434                 case ELF_AR_EC_OFFSET:
1435                         return unw_access_ar(info, UNW_AR_EC, data,
1436                                              write_access);
1437                 case ELF_AR_CSD_OFFSET:
1438                         ptr = &pt->ar_csd;
1439                         break;
1440                 case ELF_AR_SSD_OFFSET:
1441                         ptr = &pt->ar_ssd;
1442                 }
1443         } else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
1444                 switch (addr) {
1445                 case ELF_CR_IIP_OFFSET:
1446                         ptr = &pt->cr_iip;
1447                         break;
1448                 case ELF_CFM_OFFSET:
1449                         urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
1450                         if (write_access) {
1451                                 if (((cfm ^ *data) & PFM_MASK) != 0) {
1452                                         if (in_syscall(pt))
1453                                                 convert_to_non_syscall(target,
1454                                                                        pt,
1455                                                                        cfm);
1456                                         pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
1457                                                       | (*data & PFM_MASK));
1458                                 }
1459                         } else
1460                                 *data = cfm;
1461                         return 0;
1462                 case ELF_CR_IPSR_OFFSET:
1463                         if (write_access) {
1464                                 unsigned long tmp = *data;
1465                                 /* psr.ri==3 is a reserved value: SDM 2:25 */
1466                                 if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
1467                                         tmp &= ~IA64_PSR_RI;
1468                                 pt->cr_ipsr = ((tmp & IPSR_MASK)
1469                                                | (pt->cr_ipsr & ~IPSR_MASK));
1470                         } else
1471                                 *data = (pt->cr_ipsr & IPSR_MASK);
1472                         return 0;
1473                 }
1474         } else if (addr == ELF_NAT_OFFSET)
1475                 return access_nat_bits(target, pt, info,
1476                                        data, write_access);
1477         else if (addr == ELF_PR_OFFSET)
1478                 ptr = &pt->pr;
1479         else
1480                 return -1;
1481 
1482         if (write_access)
1483                 *ptr = *data;
1484         else
1485                 *data = *ptr;
1486 
1487         return 0;
1488 }
1489 
1490 static int
1491 access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
1492                 unsigned long addr, unsigned long *data, int write_access)
1493 {
1494         if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(15))
1495                 return access_elf_gpreg(target, info, addr, data, write_access);
1496         else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
1497                 return access_elf_breg(target, info, addr, data, write_access);
1498         else
1499                 return access_elf_areg(target, info, addr, data, write_access);
1500 }
1501 
1502 void do_gpregs_get(struct unw_frame_info *info, void *arg)
1503 {
1504         struct pt_regs *pt;
1505         struct regset_getset *dst = arg;
1506         elf_greg_t tmp[16];
1507         unsigned int i, index, min_copy;
1508 
1509         if (unw_unwind_to_user(info) < 0)
1510                 return;
1511 
1512         /*
1513          * coredump format:
1514          *      r0-r31
1515          *      NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
1516          *      predicate registers (p0-p63)
1517          *      b0-b7
1518          *      ip cfm user-mask
1519          *      ar.rsc ar.bsp ar.bspstore ar.rnat
1520          *      ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
1521          */
1522 
1523 
1524         /* Skip r0 */
1525         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1526                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1527                                                       &dst->u.get.kbuf,
1528                                                       &dst->u.get.ubuf,
1529                                                       0, ELF_GR_OFFSET(1));
1530                 if (dst->ret || dst->count == 0)
1531                         return;
1532         }
1533 
1534         /* gr1 - gr15 */
1535         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1536                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1537                 min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
1538                          (dst->pos + dst->count) : ELF_GR_OFFSET(16);
1539                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1540                                 index++)
1541                         if (access_elf_reg(dst->target, info, i,
1542                                                 &tmp[index], 0) < 0) {
1543                                 dst->ret = -EIO;
1544                                 return;
1545                         }
1546                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1547                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1548                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1549                 if (dst->ret || dst->count == 0)
1550                         return;
1551         }
1552 
1553         /* r16-r31 */
1554         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1555                 pt = task_pt_regs(dst->target);
1556                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1557                                 &dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
1558                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1559                 if (dst->ret || dst->count == 0)
1560                         return;
1561         }
1562 
1563         /* nat, pr, b0 - b7 */
1564         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1565                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1566                 min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
1567                          (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
1568                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1569                                 index++)
1570                         if (access_elf_reg(dst->target, info, i,
1571                                                 &tmp[index], 0) < 0) {
1572                                 dst->ret = -EIO;
1573                                 return;
1574                         }
1575                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1576                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1577                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1578                 if (dst->ret || dst->count == 0)
1579                         return;
1580         }
1581 
1582         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1583          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1584          */
1585         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1586                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1587                 min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
1588                          (dst->pos + dst->count) : ELF_AR_END_OFFSET;
1589                 for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
1590                                 index++)
1591                         if (access_elf_reg(dst->target, info, i,
1592                                                 &tmp[index], 0) < 0) {
1593                                 dst->ret = -EIO;
1594                                 return;
1595                         }
1596                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1597                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1598                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1599         }
1600 }
1601 
1602 void do_gpregs_set(struct unw_frame_info *info, void *arg)
1603 {
1604         struct pt_regs *pt;
1605         struct regset_getset *dst = arg;
1606         elf_greg_t tmp[16];
1607         unsigned int i, index;
1608 
1609         if (unw_unwind_to_user(info) < 0)
1610                 return;
1611 
1612         /* Skip r0 */
1613         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
1614                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1615                                                        &dst->u.set.kbuf,
1616                                                        &dst->u.set.ubuf,
1617                                                        0, ELF_GR_OFFSET(1));
1618                 if (dst->ret || dst->count == 0)
1619                         return;
1620         }
1621 
1622         /* gr1-gr15 */
1623         if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
1624                 i = dst->pos;
1625                 index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
1626                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1627                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1628                                 ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
1629                 if (dst->ret)
1630                         return;
1631                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1632                         if (access_elf_reg(dst->target, info, i,
1633                                                 &tmp[index], 1) < 0) {
1634                                 dst->ret = -EIO;
1635                                 return;
1636                         }
1637                 if (dst->count == 0)
1638                         return;
1639         }
1640 
1641         /* gr16-gr31 */
1642         if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
1643                 pt = task_pt_regs(dst->target);
1644                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1645                                 &dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
1646                                 ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
1647                 if (dst->ret || dst->count == 0)
1648                         return;
1649         }
1650 
1651         /* nat, pr, b0 - b7 */
1652         if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
1653                 i = dst->pos;
1654                 index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
1655                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1656                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1657                                 ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
1658                 if (dst->ret)
1659                         return;
1660                 for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
1661                         if (access_elf_reg(dst->target, info, i,
1662                                                 &tmp[index], 1) < 0) {
1663                                 dst->ret = -EIO;
1664                                 return;
1665                         }
1666                 if (dst->count == 0)
1667                         return;
1668         }
1669 
1670         /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
1671          * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
1672          */
1673         if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
1674                 i = dst->pos;
1675                 index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
1676                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1677                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1678                                 ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
1679                 if (dst->ret)
1680                         return;
1681                 for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
1682                         if (access_elf_reg(dst->target, info, i,
1683                                                 &tmp[index], 1) < 0) {
1684                                 dst->ret = -EIO;
1685                                 return;
1686                         }
1687         }
1688 }
1689 
1690 #define ELF_FP_OFFSET(i)        (i * sizeof(elf_fpreg_t))
1691 
1692 void do_fpregs_get(struct unw_frame_info *info, void *arg)
1693 {
1694         struct regset_getset *dst = arg;
1695         struct task_struct *task = dst->target;
1696         elf_fpreg_t tmp[30];
1697         int index, min_copy, i;
1698 
1699         if (unw_unwind_to_user(info) < 0)
1700                 return;
1701 
1702         /* Skip pos 0 and 1 */
1703         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1704                 dst->ret = user_regset_copyout_zero(&dst->pos, &dst->count,
1705                                                       &dst->u.get.kbuf,
1706                                                       &dst->u.get.ubuf,
1707                                                       0, ELF_FP_OFFSET(2));
1708                 if (dst->count == 0 || dst->ret)
1709                         return;
1710         }
1711 
1712         /* fr2-fr31 */
1713         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1714                 index = (dst->pos - ELF_FP_OFFSET(2)) / sizeof(elf_fpreg_t);
1715 
1716                 min_copy = min(((unsigned int)ELF_FP_OFFSET(32)),
1717                                 dst->pos + dst->count);
1718                 for (i = dst->pos; i < min_copy; i += sizeof(elf_fpreg_t),
1719                                 index++)
1720                         if (unw_get_fr(info, i / sizeof(elf_fpreg_t),
1721                                          &tmp[index])) {
1722                                 dst->ret = -EIO;
1723                                 return;
1724                         }
1725                 dst->ret = user_regset_copyout(&dst->pos, &dst->count,
1726                                 &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
1727                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1728                 if (dst->count == 0 || dst->ret)
1729                         return;
1730         }
1731 
1732         /* fph */
1733         if (dst->count > 0) {
1734                 ia64_flush_fph(dst->target);
1735                 if (task->thread.flags & IA64_THREAD_FPH_VALID)
1736                         dst->ret = user_regset_copyout(
1737                                 &dst->pos, &dst->count,
1738                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1739                                 &dst->target->thread.fph,
1740                                 ELF_FP_OFFSET(32), -1);
1741                 else
1742                         /* Zero fill instead.  */
1743                         dst->ret = user_regset_copyout_zero(
1744                                 &dst->pos, &dst->count,
1745                                 &dst->u.get.kbuf, &dst->u.get.ubuf,
1746                                 ELF_FP_OFFSET(32), -1);
1747         }
1748 }
1749 
1750 void do_fpregs_set(struct unw_frame_info *info, void *arg)
1751 {
1752         struct regset_getset *dst = arg;
1753         elf_fpreg_t fpreg, tmp[30];
1754         int index, start, end;
1755 
1756         if (unw_unwind_to_user(info) < 0)
1757                 return;
1758 
1759         /* Skip pos 0 and 1 */
1760         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
1761                 dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
1762                                                        &dst->u.set.kbuf,
1763                                                        &dst->u.set.ubuf,
1764                                                        0, ELF_FP_OFFSET(2));
1765                 if (dst->count == 0 || dst->ret)
1766                         return;
1767         }
1768 
1769         /* fr2-fr31 */
1770         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
1771                 start = dst->pos;
1772                 end = min(((unsigned int)ELF_FP_OFFSET(32)),
1773                          dst->pos + dst->count);
1774                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1775                                 &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
1776                                 ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
1777                 if (dst->ret)
1778                         return;
1779 
1780                 if (start & 0xF) { /* only write high part */
1781                         if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
1782                                          &fpreg)) {
1783                                 dst->ret = -EIO;
1784                                 return;
1785                         }
1786                         tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
1787                                 = fpreg.u.bits[0];
1788                         start &= ~0xFUL;
1789                 }
1790                 if (end & 0xF) { /* only write low part */
1791                         if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
1792                                         &fpreg)) {
1793                                 dst->ret = -EIO;
1794                                 return;
1795                         }
1796                         tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
1797                                 = fpreg.u.bits[1];
1798                         end = (end + 0xF) & ~0xFUL;
1799                 }
1800 
1801                 for ( ; start < end ; start += sizeof(elf_fpreg_t)) {
1802                         index = start / sizeof(elf_fpreg_t);
1803                         if (unw_set_fr(info, index, tmp[index - 2])) {
1804                                 dst->ret = -EIO;
1805                                 return;
1806                         }
1807                 }
1808                 if (dst->ret || dst->count == 0)
1809                         return;
1810         }
1811 
1812         /* fph */
1813         if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
1814                 ia64_sync_fph(dst->target);
1815                 dst->ret = user_regset_copyin(&dst->pos, &dst->count,
1816                                                 &dst->u.set.kbuf,
1817                                                 &dst->u.set.ubuf,
1818                                                 &dst->target->thread.fph,
1819                                                 ELF_FP_OFFSET(32), -1);
1820         }
1821 }
1822 
1823 static int
1824 do_regset_call(void (*call)(struct unw_frame_info *, void *),
1825                struct task_struct *target,
1826                const struct user_regset *regset,
1827                unsigned int pos, unsigned int count,
1828                const void *kbuf, const void __user *ubuf)
1829 {
1830         struct regset_getset info = { .target = target, .regset = regset,
1831                                  .pos = pos, .count = count,
1832                                  .u.set = { .kbuf = kbuf, .ubuf = ubuf },
1833                                  .ret = 0 };
1834 
1835         if (target == current)
1836                 unw_init_running(call, &info);
1837         else {
1838                 struct unw_frame_info ufi;
1839                 memset(&ufi, 0, sizeof(ufi));
1840                 unw_init_from_blocked_task(&ufi, target);
1841                 (*call)(&ufi, &info);
1842         }
1843 
1844         return info.ret;
1845 }
1846 
1847 static int
1848 gpregs_get(struct task_struct *target,
1849            const struct user_regset *regset,
1850            unsigned int pos, unsigned int count,
1851            void *kbuf, void __user *ubuf)
1852 {
1853         return do_regset_call(do_gpregs_get, target, regset, pos, count,
1854                 kbuf, ubuf);
1855 }
1856 
1857 static int gpregs_set(struct task_struct *target,
1858                 const struct user_regset *regset,
1859                 unsigned int pos, unsigned int count,
1860                 const void *kbuf, const void __user *ubuf)
1861 {
1862         return do_regset_call(do_gpregs_set, target, regset, pos, count,
1863                 kbuf, ubuf);
1864 }
1865 
1866 static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
1867 {
1868         do_sync_rbs(info, ia64_sync_user_rbs);
1869 }
1870 
1871 /*
1872  * This is called to write back the register backing store.
1873  * ptrace does this before it stops, so that a tracer reading the user
1874  * memory after the thread stops will get the current register data.
1875  */
1876 static int
1877 gpregs_writeback(struct task_struct *target,
1878                  const struct user_regset *regset,
1879                  int now)
1880 {
1881         if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
1882                 return 0;
1883         set_notify_resume(target);
1884         return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
1885                 NULL, NULL);
1886 }
1887 
1888 static int
1889 fpregs_active(struct task_struct *target, const struct user_regset *regset)
1890 {
1891         return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1892 }
1893 
1894 static int fpregs_get(struct task_struct *target,
1895                 const struct user_regset *regset,
1896                 unsigned int pos, unsigned int count,
1897                 void *kbuf, void __user *ubuf)
1898 {
1899         return do_regset_call(do_fpregs_get, target, regset, pos, count,
1900                 kbuf, ubuf);
1901 }
1902 
1903 static int fpregs_set(struct task_struct *target,
1904                 const struct user_regset *regset,
1905                 unsigned int pos, unsigned int count,
1906                 const void *kbuf, const void __user *ubuf)
1907 {
1908         return do_regset_call(do_fpregs_set, target, regset, pos, count,
1909                 kbuf, ubuf);
1910 }
1911 
1912 static int
1913 access_uarea(struct task_struct *child, unsigned long addr,
1914               unsigned long *data, int write_access)
1915 {
1916         unsigned int pos = -1; /* an invalid value */
1917         int ret;
1918         unsigned long *ptr, regnum;
1919 
1920         if ((addr & 0x7) != 0) {
1921                 dprintk("ptrace: unaligned register address 0x%lx\n", addr);
1922                 return -1;
1923         }
1924         if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
1925                 (addr >= PT_R7 + 8 && addr < PT_B1) ||
1926                 (addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
1927                 (addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
1928                 dprintk("ptrace: rejecting access to register "
1929                                         "address 0x%lx\n", addr);
1930                 return -1;
1931         }
1932 
1933         switch (addr) {
1934         case PT_F32 ... (PT_F127 + 15):
1935                 pos = addr - PT_F32 + ELF_FP_OFFSET(32);
1936                 break;
1937         case PT_F2 ... (PT_F5 + 15):
1938                 pos = addr - PT_F2 + ELF_FP_OFFSET(2);
1939                 break;
1940         case PT_F10 ... (PT_F31 + 15):
1941                 pos = addr - PT_F10 + ELF_FP_OFFSET(10);
1942                 break;
1943         case PT_F6 ... (PT_F9 + 15):
1944                 pos = addr - PT_F6 + ELF_FP_OFFSET(6);
1945                 break;
1946         }
1947 
1948         if (pos != -1) {
1949                 if (write_access)
1950                         ret = fpregs_set(child, NULL, pos,
1951                                 sizeof(unsigned long), data, NULL);
1952                 else
1953                         ret = fpregs_get(child, NULL, pos,
1954                                 sizeof(unsigned long), data, NULL);
1955                 if (ret != 0)
1956                         return -1;
1957                 return 0;
1958         }
1959 
1960         switch (addr) {
1961         case PT_NAT_BITS:
1962                 pos = ELF_NAT_OFFSET;
1963                 break;
1964         case PT_R4 ... PT_R7:
1965                 pos = addr - PT_R4 + ELF_GR_OFFSET(4);
1966                 break;
1967         case PT_B1 ... PT_B5:
1968                 pos = addr - PT_B1 + ELF_BR_OFFSET(1);
1969                 break;
1970         case PT_AR_EC:
1971                 pos = ELF_AR_EC_OFFSET;
1972                 break;
1973         case PT_AR_LC:
1974                 pos = ELF_AR_LC_OFFSET;
1975                 break;
1976         case PT_CR_IPSR:
1977                 pos = ELF_CR_IPSR_OFFSET;
1978                 break;
1979         case PT_CR_IIP:
1980                 pos = ELF_CR_IIP_OFFSET;
1981                 break;
1982         case PT_CFM:
1983                 pos = ELF_CFM_OFFSET;
1984                 break;
1985         case PT_AR_UNAT:
1986                 pos = ELF_AR_UNAT_OFFSET;
1987                 break;
1988         case PT_AR_PFS:
1989                 pos = ELF_AR_PFS_OFFSET;
1990                 break;
1991         case PT_AR_RSC:
1992                 pos = ELF_AR_RSC_OFFSET;
1993                 break;
1994         case PT_AR_RNAT:
1995                 pos = ELF_AR_RNAT_OFFSET;
1996                 break;
1997         case PT_AR_BSPSTORE:
1998                 pos = ELF_AR_BSPSTORE_OFFSET;
1999                 break;
2000         case PT_PR:
2001                 pos = ELF_PR_OFFSET;
2002                 break;
2003         case PT_B6:
2004                 pos = ELF_BR_OFFSET(6);
2005                 break;
2006         case PT_AR_BSP:
2007                 pos = ELF_AR_BSP_OFFSET;
2008                 break;
2009         case PT_R1 ... PT_R3:
2010                 pos = addr - PT_R1 + ELF_GR_OFFSET(1);
2011                 break;
2012         case PT_R12 ... PT_R15:
2013                 pos = addr - PT_R12 + ELF_GR_OFFSET(12);
2014                 break;
2015         case PT_R8 ... PT_R11:
2016                 pos = addr - PT_R8 + ELF_GR_OFFSET(8);
2017                 break;
2018         case PT_R16 ... PT_R31:
2019                 pos = addr - PT_R16 + ELF_GR_OFFSET(16);
2020                 break;
2021         case PT_AR_CCV:
2022                 pos = ELF_AR_CCV_OFFSET;
2023                 break;
2024         case PT_AR_FPSR:
2025                 pos = ELF_AR_FPSR_OFFSET;
2026                 break;
2027         case PT_B0:
2028                 pos = ELF_BR_OFFSET(0);
2029                 break;
2030         case PT_B7:
2031                 pos = ELF_BR_OFFSET(7);
2032                 break;
2033         case PT_AR_CSD:
2034                 pos = ELF_AR_CSD_OFFSET;
2035                 break;
2036         case PT_AR_SSD:
2037                 pos = ELF_AR_SSD_OFFSET;
2038                 break;
2039         }
2040 
2041         if (pos != -1) {
2042                 if (write_access)
2043                         ret = gpregs_set(child, NULL, pos,
2044                                 sizeof(unsigned long), data, NULL);
2045                 else
2046                         ret = gpregs_get(child, NULL, pos,
2047                                 sizeof(unsigned long), data, NULL);
2048                 if (ret != 0)
2049                         return -1;
2050                 return 0;
2051         }
2052 
2053         /* access debug registers */
2054         if (addr >= PT_IBR) {
2055                 regnum = (addr - PT_IBR) >> 3;
2056                 ptr = &child->thread.ibr[0];
2057         } else {
2058                 regnum = (addr - PT_DBR) >> 3;
2059                 ptr = &child->thread.dbr[0];
2060         }
2061 
2062         if (regnum >= 8) {
2063                 dprintk("ptrace: rejecting access to register "
2064                                 "address 0x%lx\n", addr);
2065                 return -1;
2066         }
2067 #ifdef CONFIG_PERFMON
2068         /*
2069          * Check if debug registers are used by perfmon. This
2070          * test must be done once we know that we can do the
2071          * operation, i.e. the arguments are all valid, but
2072          * before we start modifying the state.
2073          *
2074          * Perfmon needs to keep a count of how many processes
2075          * are trying to modify the debug registers for system
2076          * wide monitoring sessions.
2077          *
2078          * We also include read access here, because they may
2079          * cause the PMU-installed debug register state
2080          * (dbr[], ibr[]) to be reset. The two arrays are also
2081          * used by perfmon, but we do not use
2082          * IA64_THREAD_DBG_VALID. The registers are restored
2083          * by the PMU context switch code.
2084          */
2085         if (pfm_use_debug_registers(child))
2086                 return -1;
2087 #endif
2088 
2089         if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
2090                 child->thread.flags |= IA64_THREAD_DBG_VALID;
2091                 memset(child->thread.dbr, 0,
2092                                 sizeof(child->thread.dbr));
2093                 memset(child->thread.ibr, 0,
2094                                 sizeof(child->thread.ibr));
2095         }
2096 
2097         ptr += regnum;
2098 
2099         if ((regnum & 1) && write_access) {
2100                 /* don't let the user set kernel-level breakpoints: */
2101                 *ptr = *data & ~(7UL << 56);
2102                 return 0;
2103         }
2104         if (write_access)
2105                 *ptr = *data;
2106         else
2107                 *data = *ptr;
2108         return 0;
2109 }
2110 
2111 static const struct user_regset native_regsets[] = {
2112         {
2113                 .core_note_type = NT_PRSTATUS,
2114                 .n = ELF_NGREG,
2115                 .size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
2116                 .get = gpregs_get, .set = gpregs_set,
2117                 .writeback = gpregs_writeback
2118         },
2119         {
2120                 .core_note_type = NT_PRFPREG,
2121                 .n = ELF_NFPREG,
2122                 .size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
2123                 .get = fpregs_get, .set = fpregs_set, .active = fpregs_active
2124         },
2125 };
2126 
2127 static const struct user_regset_view user_ia64_view = {
2128         .name = "ia64",
2129         .e_machine = EM_IA_64,
2130         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
2131 };
2132 
2133 const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2134 {
2135         return &user_ia64_view;
2136 }
2137 
2138 struct syscall_get_set_args {
2139         unsigned int i;
2140         unsigned int n;
2141         unsigned long *args;
2142         struct pt_regs *regs;
2143         int rw;
2144 };
2145 
2146 static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
2147 {
2148         struct syscall_get_set_args *args = data;
2149         struct pt_regs *pt = args->regs;
2150         unsigned long *krbs, cfm, ndirty;
2151         int i, count;
2152 
2153         if (unw_unwind_to_user(info) < 0)
2154                 return;
2155 
2156         cfm = pt->cr_ifs;
2157         krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
2158         ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
2159 
2160         count = 0;
2161         if (in_syscall(pt))
2162                 count = min_t(int, args->n, cfm & 0x7f);
2163 
2164         for (i = 0; i < count; i++) {
2165                 if (args->rw)
2166                         *ia64_rse_skip_regs(krbs, ndirty + i + args->i) =
2167                                 args->args[i];
2168                 else
2169                         args->args[i] = *ia64_rse_skip_regs(krbs,
2170                                 ndirty + i + args->i);
2171         }
2172 
2173         if (!args->rw) {
2174                 while (i < args->n) {
2175                         args->args[i] = 0;
2176                         i++;
2177                 }
2178         }
2179 }
2180 
2181 void ia64_syscall_get_set_arguments(struct task_struct *task,
2182         struct pt_regs *regs, unsigned long *args, int rw)
2183 {
2184         struct syscall_get_set_args data = {
2185                 .i = 0,
2186                 .n = 6,
2187                 .args = args,
2188                 .regs = regs,
2189                 .rw = rw,
2190         };
2191 
2192         if (task == current)
2193                 unw_init_running(syscall_get_set_args_cb, &data);
2194         else {
2195                 struct unw_frame_info ufi;
2196                 memset(&ufi, 0, sizeof(ufi));
2197                 unw_init_from_blocked_task(&ufi, task);
2198                 syscall_get_set_args_cb(&ufi, &data);
2199         }
2200 }
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root/arch/ia64/kernel/ptrace.c

DEFINITIONS
