linux/arch/ia64/kernel/ptrace.c
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   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
  66static inline int
  67in_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 */
  76unsigned long
  77ia64_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 */
 115unsigned long
 116ia64_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
 153void
 154ia64_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
 176void
 177ia64_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 */
 251static unsigned long
 252get_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 */
 311static void
 312put_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
 384static inline int
 385on_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 */
 404long
 405ia64_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
 466long
 467ia64_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 */
 510unsigned long
 511ia64_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 */
 538long
 539ia64_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
 558static long
 559ia64_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
 579typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
 580                            unsigned long, unsigned long);
 581
 582static 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 */
 606void 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 */
 617void 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 */
 632void
 633ptrace_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 */
 684inline void
 685ia64_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 */
 710void
 711ia64_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 */
 728static void
 729convert_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
 788static int
 789access_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
 823static int
 824access_uarea (struct task_struct *child, unsigned long addr,
 825              unsigned long *data, int write_access);
 826
 827static long
 828ptrace_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
 971static long
 972ptrace_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
1117void
1118user_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
1126void
1127user_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
1135void
1136user_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 */
1151void
1152ptrace_disable (struct task_struct *child)
1153{
1154        user_disable_single_step(child);
1155}
1156
1157long
1158arch_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
1215asmlinkage long
1216syscall_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
1236asmlinkage void
1237syscall_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 */
1255struct regset_get {
1256        void *kbuf;
1257        void __user *ubuf;
1258};
1259
1260struct regset_set {
1261        const void *kbuf;
1262        const void __user *ubuf;
1263};
1264
1265struct 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
1277static int
1278access_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
1325static int
1326access_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
1353static int
1354access_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
1490static int
1491access_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
1502void 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
1602void 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
1692void 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
1750void 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
1823static int
1824do_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
1847static int
1848gpregs_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
1857static 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
1866static 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 */
1876static int
1877gpregs_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
1888static int
1889fpregs_active(struct task_struct *target, const struct user_regset *regset)
1890{
1891        return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
1892}
1893
1894static 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
1903static 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
1912static int
1913access_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
2111static 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
2127static 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
2133const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
2134{
2135        return &user_ia64_view;
2136}
2137
2138struct 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
2146static 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
2181void 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}
2201