arch/sparc/kernel/sys_sparc_64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* linux/arch/sparc64/kernel/sys_sparc.c
   3  *
   4  * This file contains various random system calls that
   5  * have a non-standard calling sequence on the Linux/sparc
   6  * platform.
   7  */
   8
   9 #include <linux/errno.h>
  10 #include <linux/types.h>
  11 #include <linux/sched/signal.h>
  12 #include <linux/sched/mm.h>
  13 #include <linux/sched/debug.h>
  14 #include <linux/fs.h>
  15 #include <linux/file.h>
  16 #include <linux/mm.h>
  17 #include <linux/sem.h>
  18 #include <linux/msg.h>
  19 #include <linux/shm.h>
  20 #include <linux/stat.h>
  21 #include <linux/mman.h>
  22 #include <linux/utsname.h>
  23 #include <linux/smp.h>
  24 #include <linux/slab.h>
  25 #include <linux/syscalls.h>
  26 #include <linux/ipc.h>
  27 #include <linux/personality.h>
  28 #include <linux/random.h>
  29 #include <linux/export.h>
  30 #include <linux/context_tracking.h>
  31 #include <linux/timex.h>
  32 #include <linux/uaccess.h>
  33 #include <linux/hugetlb.h>
  34
  35 #include <asm/utrap.h>
  36 #include <asm/unistd.h>
  37
  38 #include "entry.h"
  39 #include "kernel.h"
  40 #include "systbls.h"
  41
  42 /* #define DEBUG_UNIMP_SYSCALL */
  43
  44 SYSCALL_DEFINE0(getpagesize)
  45 {
  46         return PAGE_SIZE;
  47 }
  48
  49 /* Does addr --> addr+len fall within 4GB of the VA-space hole or
  50  * overflow past the end of the 64-bit address space?
  51  */
  52 static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
  53 {
  54         unsigned long va_exclude_start, va_exclude_end;
  55
  56         va_exclude_start = VA_EXCLUDE_START;
  57         va_exclude_end   = VA_EXCLUDE_END;
  58
  59         if (unlikely(len >= va_exclude_start))
  60                 return 1;
  61
  62         if (unlikely((addr + len) < addr))
  63                 return 1;
  64
  65         if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
  66                      ((addr + len) >= va_exclude_start &&
  67                       (addr + len) < va_exclude_end)))
  68                 return 1;
  69
  70         return 0;
  71 }
  72
  73 /* These functions differ from the default implementations in
  74  * mm/mmap.c in two ways:
  75  *
  76  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
  77  *    for fixed such mappings we just validate what the user gave us.
  78  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
  79  *    the spitfire/niagara VA-hole.
  80  */
  81
  82 static inline unsigned long COLOR_ALIGN(unsigned long addr,
  83                                          unsigned long pgoff)
  84 {
  85         unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
  86         unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
  87
  88         return base + off;
  89 }
  90
  91 static unsigned long get_align_mask(struct file *filp, unsigned long flags)
  92 {
  93         if (filp && is_file_hugepages(filp))
  94                 return huge_page_mask_align(filp);
  95         if (filp || (flags & MAP_SHARED))
  96                 return PAGE_MASK & (SHMLBA - 1);
  97
  98         return 0;
  99 }
 100
 101 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags)
 102 {
 103         struct mm_struct *mm = current->mm;
 104         struct vm_area_struct * vma;
 105         unsigned long task_size = TASK_SIZE;
 106         int do_color_align;
 107         struct vm_unmapped_area_info info = {};
 108         bool file_hugepage = false;
 109
 110         if (filp && is_file_hugepages(filp))
 111                 file_hugepage = true;
 112
 113         if (flags & MAP_FIXED) {
 114                 /* We do not accept a shared mapping if it would violate
 115                  * cache aliasing constraints.
 116                  */
 117                 if (!file_hugepage && (flags & MAP_SHARED) &&
 118                     ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 119                         return -EINVAL;
 120                 return addr;
 121         }
 122
 123         if (test_thread_flag(TIF_32BIT))
 124                 task_size = STACK_TOP32;
 125         if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
 126                 return -ENOMEM;
 127
 128         do_color_align = 0;
 129         if ((filp || (flags & MAP_SHARED)) && !file_hugepage)
 130                 do_color_align = 1;
 131
 132         if (addr) {
 133                 if (do_color_align)
 134                         addr = COLOR_ALIGN(addr, pgoff);
 135                 else
 136                         addr = PAGE_ALIGN(addr);
 137
 138                 vma = find_vma(mm, addr);
 139                 if (task_size - len >= addr &&
 140                     (!vma || addr + len <= vm_start_gap(vma)))
 141                         return addr;
 142         }
 143
 144         info.length = len;
 145         info.low_limit = TASK_UNMAPPED_BASE;
 146         info.high_limit = min(task_size, VA_EXCLUDE_START);
 147         info.align_mask = get_align_mask(filp, flags);
 148         if (!file_hugepage)
 149                 info.align_offset = pgoff << PAGE_SHIFT;
 150         addr = vm_unmapped_area(&info);
 151
 152         if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
 153                 VM_BUG_ON(addr != -ENOMEM);
 154                 info.low_limit = VA_EXCLUDE_END;
 155                 info.high_limit = task_size;
 156                 addr = vm_unmapped_area(&info);
 157         }
 158
 159         return addr;
 160 }
 161
 162 unsigned long
 163 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 164                           const unsigned long len, const unsigned long pgoff,
 165                           const unsigned long flags, vm_flags_t vm_flags)
 166 {
 167         struct vm_area_struct *vma;
 168         struct mm_struct *mm = current->mm;
 169         unsigned long task_size = STACK_TOP32;
 170         unsigned long addr = addr0;
 171         int do_color_align;
 172         struct vm_unmapped_area_info info = {};
 173         bool file_hugepage = false;
 174
 175         /* This should only ever run for 32-bit processes.  */
 176         BUG_ON(!test_thread_flag(TIF_32BIT));
 177
 178         if (filp && is_file_hugepages(filp))
 179                 file_hugepage = true;
 180
 181         if (flags & MAP_FIXED) {
 182                 /* We do not accept a shared mapping if it would violate
 183                  * cache aliasing constraints.
 184                  */
 185                 if (!file_hugepage && (flags & MAP_SHARED) &&
 186                     ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 187                         return -EINVAL;
 188                 return addr;
 189         }
 190
 191         if (unlikely(len > task_size))
 192                 return -ENOMEM;
 193
 194         do_color_align = 0;
 195         if ((filp || (flags & MAP_SHARED)) && !file_hugepage)
 196                 do_color_align = 1;
 197
 198         /* requesting a specific address */
 199         if (addr) {
 200                 if (do_color_align)
 201                         addr = COLOR_ALIGN(addr, pgoff);
 202                 else
 203                         addr = PAGE_ALIGN(addr);
 204
 205                 vma = find_vma(mm, addr);
 206                 if (task_size - len >= addr &&
 207                     (!vma || addr + len <= vm_start_gap(vma)))
 208                         return addr;
 209         }
 210
 211         info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 212         info.length = len;
 213         info.low_limit = PAGE_SIZE;
 214         info.high_limit = mm->mmap_base;
 215         info.align_mask = get_align_mask(filp, flags);
 216         if (!file_hugepage)
 217                 info.align_offset = pgoff << PAGE_SHIFT;
 218         addr = vm_unmapped_area(&info);
 219
 220         /*
 221          * A failed mmap() very likely causes application failure,
 222          * so fall back to the bottom-up function here. This scenario
 223          * can happen with large stack limits and large mmap()
 224          * allocations.
 225          */
 226         if (addr & ~PAGE_MASK) {
 227                 VM_BUG_ON(addr != -ENOMEM);
 228                 info.flags = 0;
 229                 info.low_limit = TASK_UNMAPPED_BASE;
 230                 info.high_limit = STACK_TOP32;
 231                 addr = vm_unmapped_area(&info);
 232         }
 233
 234         return addr;
 235 }
 236
 237 /* Try to align mapping such that we align it as much as possible. */
 238 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
 239 {
 240         unsigned long align_goal, addr = -ENOMEM;
 241
 242         if (flags & MAP_FIXED) {
 243                 /* Ok, don't mess with it. */
 244                 return mm_get_unmapped_area(current->mm, NULL, orig_addr, len, pgoff, flags);
 245         }
 246         flags &= ~MAP_SHARED;
 247
 248         align_goal = PAGE_SIZE;
 249         if (len >= (4UL * 1024 * 1024))
 250                 align_goal = (4UL * 1024 * 1024);
 251         else if (len >= (512UL * 1024))
 252                 align_goal = (512UL * 1024);
 253         else if (len >= (64UL * 1024))
 254                 align_goal = (64UL * 1024);
 255
 256         do {
 257                 addr = mm_get_unmapped_area(current->mm, NULL, orig_addr,
 258                                             len + (align_goal - PAGE_SIZE), pgoff, flags);
 259                 if (!(addr & ~PAGE_MASK)) {
 260                         addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
 261                         break;
 262                 }
 263
 264                 if (align_goal == (4UL * 1024 * 1024))
 265                         align_goal = (512UL * 1024);
 266                 else if (align_goal == (512UL * 1024))
 267                         align_goal = (64UL * 1024);
 268                 else
 269                         align_goal = PAGE_SIZE;
 270         } while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
 271
 272         /* Mapping is smaller than 64K or larger areas could not
 273          * be obtained.
 274          */
 275         if (addr & ~PAGE_MASK)
 276                 addr = mm_get_unmapped_area(current->mm, NULL, orig_addr, len, pgoff, flags);
 277
 278         return addr;
 279 }
 280 EXPORT_SYMBOL(get_fb_unmapped_area);
 281
 282 /* Essentially the same as PowerPC.  */
 283 static unsigned long mmap_rnd(void)
 284 {
 285         unsigned long rnd = 0UL;
 286
 287         if (current->flags & PF_RANDOMIZE) {
 288                 unsigned long val = get_random_long();
 289                 if (test_thread_flag(TIF_32BIT))
 290                         rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
 291                 else
 292                         rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
 293         }
 294         return rnd << PAGE_SHIFT;
 295 }
 296
 297 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 298 {
 299         unsigned long random_factor = mmap_rnd();
 300         unsigned long gap;
 301
 302         /*
 303          * Fall back to the standard layout if the personality
 304          * bit is set, or if the expected stack growth is unlimited:
 305          */
 306         gap = rlim_stack->rlim_cur;
 307         if (!test_thread_flag(TIF_32BIT) ||
 308             (current->personality & ADDR_COMPAT_LAYOUT) ||
 309             gap == RLIM_INFINITY ||
 310             sysctl_legacy_va_layout) {
 311                 mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
 312                 clear_bit(MMF_TOPDOWN, &mm->flags);
 313         } else {
 314                 /* We know it's 32-bit */
 315                 unsigned long task_size = STACK_TOP32;
 316
 317                 if (gap < 128 * 1024 * 1024)
 318                         gap = 128 * 1024 * 1024;
 319                 if (gap > (task_size / 6 * 5))
 320                         gap = (task_size / 6 * 5);
 321
 322                 mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
 323                 set_bit(MMF_TOPDOWN, &mm->flags);
 324         }
 325 }
 326
 327 /*
 328  * sys_pipe() is the normal C calling standard for creating
 329  * a pipe. It's not the way unix traditionally does this, though.
 330  */
 331 SYSCALL_DEFINE0(sparc_pipe)
 332 {
 333         int fd[2];
 334         int error;
 335
 336         error = do_pipe_flags(fd, 0);
 337         if (error)
 338                 goto out;
 339         current_pt_regs()->u_regs[UREG_I1] = fd[1];
 340         error = fd[0];
 341 out:
 342         return error;
 343 }
 344
 345 /*
 346  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 347  *
 348  * This is really horribly ugly.
 349  */
 350
 351 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
 352                 unsigned long, third, void __user *, ptr, long, fifth)
 353 {
 354         long err;
 355
 356         if (!IS_ENABLED(CONFIG_SYSVIPC))
 357                 return -ENOSYS;
 358
 359         /* No need for backward compatibility. We can start fresh... */
 360         if (call <= SEMTIMEDOP) {
 361                 switch (call) {
 362                 case SEMOP:
 363                         err = ksys_semtimedop(first, ptr,
 364                                               (unsigned int)second, NULL);
 365                         goto out;
 366                 case SEMTIMEDOP:
 367                         err = ksys_semtimedop(first, ptr, (unsigned int)second,
 368                                 (const struct __kernel_timespec __user *)
 369                                               (unsigned long) fifth);
 370                         goto out;
 371                 case SEMGET:
 372                         err = ksys_semget(first, (int)second, (int)third);
 373                         goto out;
 374                 case SEMCTL: {
 375                         err = ksys_old_semctl(first, second,
 376                                               (int)third | IPC_64,
 377                                               (unsigned long) ptr);
 378                         goto out;
 379                 }
 380                 default:
 381                         err = -ENOSYS;
 382                         goto out;
 383                 }
 384         }
 385         if (call <= MSGCTL) {
 386                 switch (call) {
 387                 case MSGSND:
 388                         err = ksys_msgsnd(first, ptr, (size_t)second,
 389                                          (int)third);
 390                         goto out;
 391                 case MSGRCV:
 392                         err = ksys_msgrcv(first, ptr, (size_t)second, fifth,
 393                                          (int)third);
 394                         goto out;
 395                 case MSGGET:
 396                         err = ksys_msgget((key_t)first, (int)second);
 397                         goto out;
 398                 case MSGCTL:
 399                         err = ksys_old_msgctl(first, (int)second | IPC_64, ptr);
 400                         goto out;
 401                 default:
 402                         err = -ENOSYS;
 403                         goto out;
 404                 }
 405         }
 406         if (call <= SHMCTL) {
 407                 switch (call) {
 408                 case SHMAT: {
 409                         ulong raddr;
 410                         err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
 411                         if (!err) {
 412                                 if (put_user(raddr,
 413                                              (ulong __user *) third))
 414                                         err = -EFAULT;
 415                         }
 416                         goto out;
 417                 }
 418                 case SHMDT:
 419                         err = ksys_shmdt(ptr);
 420                         goto out;
 421                 case SHMGET:
 422                         err = ksys_shmget(first, (size_t)second, (int)third);
 423                         goto out;
 424                 case SHMCTL:
 425                         err = ksys_old_shmctl(first, (int)second | IPC_64, ptr);
 426                         goto out;
 427                 default:
 428                         err = -ENOSYS;
 429                         goto out;
 430                 }
 431         } else {
 432                 err = -ENOSYS;
 433         }
 434 out:
 435         return err;
 436 }
 437
 438 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
 439 {
 440         long ret;
 441
 442         if (personality(current->personality) == PER_LINUX32 &&
 443             personality(personality) == PER_LINUX)
 444                 personality |= PER_LINUX32;
 445         ret = sys_personality(personality);
 446         if (personality(ret) == PER_LINUX32)
 447                 ret &= ~PER_LINUX32;
 448
 449         return ret;
 450 }
 451
 452 int sparc_mmap_check(unsigned long addr, unsigned long len)
 453 {
 454         if (test_thread_flag(TIF_32BIT)) {
 455                 if (len >= STACK_TOP32)
 456                         return -EINVAL;
 457
 458                 if (addr > STACK_TOP32 - len)
 459                         return -EINVAL;
 460         } else {
 461                 if (len >= VA_EXCLUDE_START)
 462                         return -EINVAL;
 463
 464                 if (invalid_64bit_range(addr, len))
 465                         return -EINVAL;
 466         }
 467
 468         return 0;
 469 }
 470
 471 /* Linux version of mmap */
 472 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 473                 unsigned long, prot, unsigned long, flags, unsigned long, fd,
 474                 unsigned long, off)
 475 {
 476         unsigned long retval = -EINVAL;
 477
 478         if ((off + PAGE_ALIGN(len)) < off)
 479                 goto out;
 480         if (off & ~PAGE_MASK)
 481                 goto out;
 482         retval = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 483 out:
 484         return retval;
 485 }
 486
 487 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
 488 {
 489         if (invalid_64bit_range(addr, len))
 490                 return -EINVAL;
 491
 492         return vm_munmap(addr, len);
 493 }
 494
 495 SYSCALL_DEFINE5(64_mremap, unsigned long, addr, unsigned long, old_len,
 496                 unsigned long, new_len, unsigned long, flags,
 497                 unsigned long, new_addr)
 498 {
 499         if (test_thread_flag(TIF_32BIT))
 500                 return -EINVAL;
 501         return sys_mremap(addr, old_len, new_len, flags, new_addr);
 502 }
 503
 504 SYSCALL_DEFINE0(nis_syscall)
 505 {
 506         static int count;
 507         struct pt_regs *regs = current_pt_regs();
 508
 509         /* Don't make the system unusable, if someone goes stuck */
 510         if (count++ > 5)
 511                 return -ENOSYS;
 512
 513         printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
 514 #ifdef DEBUG_UNIMP_SYSCALL
 515         show_regs (regs);
 516 #endif
 517
 518         return -ENOSYS;
 519 }
 520
 521 /* #define DEBUG_SPARC_BREAKPOINT */
 522
 523 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
 524 {
 525         enum ctx_state prev_state = exception_enter();
 526
 527         if (test_thread_flag(TIF_32BIT)) {
 528                 regs->tpc &= 0xffffffff;
 529                 regs->tnpc &= 0xffffffff;
 530         }
 531 #ifdef DEBUG_SPARC_BREAKPOINT
 532         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
 533 #endif
 534         force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc);
 535 #ifdef DEBUG_SPARC_BREAKPOINT
 536         printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
 537 #endif
 538         exception_exit(prev_state);
 539 }
 540
 541 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
 542 {
 543         int nlen, err;
 544         char tmp[__NEW_UTS_LEN + 1];
 545
 546         if (len < 0)
 547                 return -EINVAL;
 548
 549         down_read(&uts_sem);
 550
 551         nlen = strlen(utsname()->domainname) + 1;
 552         err = -EINVAL;
 553         if (nlen > len)
 554                 goto out_unlock;
 555         memcpy(tmp, utsname()->domainname, nlen);
 556
 557         up_read(&uts_sem);
 558
 559         if (copy_to_user(name, tmp, nlen))
 560                 return -EFAULT;
 561         return 0;
 562
 563 out_unlock:
 564         up_read(&uts_sem);
 565         return err;
 566 }
 567
 568 SYSCALL_DEFINE1(sparc_adjtimex, struct __kernel_timex __user *, txc_p)
 569 {
 570         struct __kernel_timex txc;
 571         struct __kernel_old_timeval *tv = (void *)&txc.time;
 572         int ret;
 573
 574         /* Copy the user data space into the kernel copy
 575          * structure. But bear in mind that the structures
 576          * may change
 577          */
 578         if (copy_from_user(&txc, txc_p, sizeof(txc)))
 579                 return -EFAULT;
 580
 581         /*
 582          * override for sparc64 specific timeval type: tv_usec
 583          * is 32 bit wide instead of 64-bit in __kernel_timex
 584          */
 585         txc.time.tv_usec = tv->tv_usec;
 586         ret = do_adjtimex(&txc);
 587         tv->tv_usec = txc.time.tv_usec;
 588
 589         return copy_to_user(txc_p, &txc, sizeof(txc)) ? -EFAULT : ret;
 590 }
 591
 592 SYSCALL_DEFINE2(sparc_clock_adjtime, const clockid_t, which_clock,
 593                 struct __kernel_timex __user *, txc_p)
 594 {
 595         struct __kernel_timex txc;
 596         struct __kernel_old_timeval *tv = (void *)&txc.time;
 597         int ret;
 598
 599         if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) {
 600                 pr_err_once("process %d (%s) attempted a POSIX timer syscall "
 601                     "while CONFIG_POSIX_TIMERS is not set\n",
 602                     current->pid, current->comm);
 603
 604                 return -ENOSYS;
 605         }
 606
 607         /* Copy the user data space into the kernel copy
 608          * structure. But bear in mind that the structures
 609          * may change
 610          */
 611         if (copy_from_user(&txc, txc_p, sizeof(txc)))
 612                 return -EFAULT;
 613
 614         /*
 615          * override for sparc64 specific timeval type: tv_usec
 616          * is 32 bit wide instead of 64-bit in __kernel_timex
 617          */
 618         txc.time.tv_usec = tv->tv_usec;
 619         ret = do_clock_adjtime(which_clock, &txc);
 620         tv->tv_usec = txc.time.tv_usec;
 621
 622         return copy_to_user(txc_p, &txc, sizeof(txc)) ? -EFAULT : ret;
 623 }
 624
 625 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
 626                 utrap_handler_t, new_p, utrap_handler_t, new_d,
 627                 utrap_handler_t __user *, old_p,
 628                 utrap_handler_t __user *, old_d)
 629 {
 630         if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
 631                 return -EINVAL;
 632         if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
 633                 if (old_p) {
 634                         if (!current_thread_info()->utraps) {
 635                                 if (put_user(NULL, old_p))
 636                                         return -EFAULT;
 637                         } else {
 638                                 if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
 639                                         return -EFAULT;
 640                         }
 641                 }
 642                 if (old_d) {
 643                         if (put_user(NULL, old_d))
 644                                 return -EFAULT;
 645                 }
 646                 return 0;
 647         }
 648         if (!current_thread_info()->utraps) {
 649                 current_thread_info()->utraps =
 650                         kcalloc(UT_TRAP_INSTRUCTION_31 + 1, sizeof(long),
 651                                 GFP_KERNEL);
 652                 if (!current_thread_info()->utraps)
 653                         return -ENOMEM;
 654                 current_thread_info()->utraps[0] = 1;
 655         } else {
 656                 if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
 657                     current_thread_info()->utraps[0] > 1) {
 658                         unsigned long *p = current_thread_info()->utraps;
 659
 660                         current_thread_info()->utraps =
 661                                 kmalloc_array(UT_TRAP_INSTRUCTION_31 + 1,
 662                                               sizeof(long),
 663                                               GFP_KERNEL);
 664                         if (!current_thread_info()->utraps) {
 665                                 current_thread_info()->utraps = p;
 666                                 return -ENOMEM;
 667                         }
 668                         p[0]--;
 669                         current_thread_info()->utraps[0] = 1;
 670                         memcpy(current_thread_info()->utraps+1, p+1,
 671                                UT_TRAP_INSTRUCTION_31*sizeof(long));
 672                 }
 673         }
 674         if (old_p) {
 675                 if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
 676                         return -EFAULT;
 677         }
 678         if (old_d) {
 679                 if (put_user(NULL, old_d))
 680                         return -EFAULT;
 681         }
 682         current_thread_info()->utraps[type] = (long)new_p;
 683
 684         return 0;
 685 }
 686
 687 SYSCALL_DEFINE1(memory_ordering, unsigned long, model)
 688 {
 689         struct pt_regs *regs = current_pt_regs();
 690         if (model >= 3)
 691                 return -EINVAL;
 692         regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
 693         return 0;
 694 }
 695
 696 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
 697                 struct sigaction __user *, oact, void __user *, restorer,
 698                 size_t, sigsetsize)
 699 {
 700         struct k_sigaction new_ka, old_ka;
 701         int ret;
 702
 703         /* XXX: Don't preclude handling different sized sigset_t's.  */
 704         if (sigsetsize != sizeof(sigset_t))
 705                 return -EINVAL;
 706
 707         if (act) {
 708                 new_ka.ka_restorer = restorer;
 709                 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
 710                         return -EFAULT;
 711         }
 712
 713         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 714
 715         if (!ret && oact) {
 716                 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
 717                         return -EFAULT;
 718         }
 719
 720         return ret;
 721 }
 722
 723 SYSCALL_DEFINE0(kern_features)
 724 {
 725         return KERN_FEATURE_MIXED_MODE_STACK;
 726 }