arch/mn10300/kernel/entry.S

   1 ###############################################################################
   2 #
   3 # MN10300 Exception and interrupt entry points
   4 #
   5 # Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
   6 # Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   7 # Modified by David Howells (dhowells@redhat.com)
   8 #
   9 # This program is free software; you can redistribute it and/or
  10 # modify it under the terms of the GNU General Public Licence
  11 # as published by the Free Software Foundation; either version
  12 # 2 of the Licence, or (at your option) any later version.
  13 #
  14 ###############################################################################
  15 #include <linux/sys.h>
  16 #include <linux/linkage.h>
  17 #include <asm/smp.h>
  18 #include <asm/system.h>
  19 #include <asm/irqflags.h>
  20 #include <asm/thread_info.h>
  21 #include <asm/intctl-regs.h>
  22 #include <asm/busctl-regs.h>
  23 #include <asm/timer-regs.h>
  24 #include <unit/leds.h>
  25 #include <asm/page.h>
  26 #include <asm/pgtable.h>
  27 #include <asm/errno.h>
  28 #include <asm/asm-offsets.h>
  29 #include <asm/frame.inc>
  30
  31 #ifdef CONFIG_PREEMPT
  32 #define preempt_stop            __cli
  33 #else
  34 #define preempt_stop
  35 #define resume_kernel           restore_all
  36 #endif
  37
  38         .macro __cli
  39         and     ~EPSW_IM,epsw
  40         or      EPSW_IE|MN10300_CLI_LEVEL,epsw
  41         nop
  42         nop
  43         nop
  44         .endm
  45         .macro __sti
  46         or      EPSW_IE|EPSW_IM_7,epsw
  47         .endm
  48
  49
  50         .am33_2
  51
  52 ###############################################################################
  53 #
  54 # the return path for a forked child
  55 # - on entry, D0 holds the address of the previous task to run
  56 #
  57 ###############################################################################
  58 ENTRY(ret_from_fork)
  59         call    schedule_tail[],0
  60         GET_THREAD_INFO a2
  61
  62         # return 0 to indicate child process
  63         clr     d0
  64         mov     d0,(REG_D0,fp)
  65         jmp     syscall_exit
  66
  67 ###############################################################################
  68 #
  69 # system call handler
  70 #
  71 ###############################################################################
  72 ENTRY(system_call)
  73         add     -4,sp
  74         SAVE_ALL
  75         mov     d0,(REG_ORIG_D0,fp)
  76         GET_THREAD_INFO a2
  77         cmp     nr_syscalls,d0
  78         bcc     syscall_badsys
  79         btst    _TIF_SYSCALL_TRACE,(TI_flags,a2)
  80         bne     syscall_entry_trace
  81 syscall_call:
  82         add     d0,d0,a1
  83         add     a1,a1
  84         mov     (REG_A0,fp),d0
  85         mov     (sys_call_table,a1),a0
  86         calls   (a0)
  87         mov     d0,(REG_D0,fp)
  88 syscall_exit:
  89         # make sure we don't miss an interrupt setting need_resched or
  90         # sigpending between sampling and the rti
  91         __cli
  92         mov     (TI_flags,a2),d2
  93         btst    _TIF_ALLWORK_MASK,d2
  94         bne     syscall_exit_work
  95 restore_all:
  96         RESTORE_ALL
  97
  98 ###############################################################################
  99 #
 100 # perform work that needs to be done immediately before resumption and syscall
 101 # tracing
 102 #
 103 ###############################################################################
 104         ALIGN
 105 syscall_exit_work:
 106         btst    _TIF_SYSCALL_TRACE,d2
 107         beq     work_pending
 108         __sti                           # could let syscall_trace_exit() call
 109                                         # schedule() instead
 110         mov     fp,d0
 111         call    syscall_trace_exit[],0  # do_syscall_trace(regs)
 112         jmp     resume_userspace
 113
 114         ALIGN
 115 work_pending:
 116         btst    _TIF_NEED_RESCHED,d2
 117         beq     work_notifysig
 118
 119 work_resched:
 120         call    schedule[],0
 121
 122         # make sure we don't miss an interrupt setting need_resched or
 123         # sigpending between sampling and the rti
 124         __cli
 125
 126         # is there any work to be done other than syscall tracing?
 127         mov     (TI_flags,a2),d2
 128         btst    _TIF_WORK_MASK,d2
 129         beq     restore_all
 130         btst    _TIF_NEED_RESCHED,d2
 131         bne     work_resched
 132
 133         # deal with pending signals and notify-resume requests
 134 work_notifysig:
 135         mov     fp,d0
 136         mov     d2,d1
 137         call    do_notify_resume[],0
 138         jmp     resume_userspace
 139
 140         # perform syscall entry tracing
 141 syscall_entry_trace:
 142         mov     -ENOSYS,d0
 143         mov     d0,(REG_D0,fp)
 144         mov     fp,d0
 145         call    syscall_trace_entry[],0 # returns the syscall number to actually use
 146         mov     (REG_D1,fp),d1
 147         cmp     nr_syscalls,d0
 148         bcs     syscall_call
 149         jmp     syscall_exit
 150
 151 syscall_badsys:
 152         mov     -ENOSYS,d0
 153         mov     d0,(REG_D0,fp)
 154         jmp     resume_userspace
 155
 156         # userspace resumption stub bypassing syscall exit tracing
 157         .globl  ret_from_exception, ret_from_intr
 158         ALIGN
 159 ret_from_exception:
 160         preempt_stop
 161 ret_from_intr:
 162         GET_THREAD_INFO a2
 163         mov     (REG_EPSW,fp),d0        # need to deliver signals before
 164                                         # returning to userspace
 165         and     EPSW_nSL,d0
 166         beq     resume_kernel           # returning to supervisor mode
 167
 168 ENTRY(resume_userspace)
 169         # make sure we don't miss an interrupt setting need_resched or
 170         # sigpending between sampling and the rti
 171         __cli
 172
 173         # is there any work to be done on int/exception return?
 174         mov     (TI_flags,a2),d2
 175         btst    _TIF_WORK_MASK,d2
 176         bne     work_pending
 177         jmp     restore_all
 178
 179 #ifdef CONFIG_PREEMPT
 180 ENTRY(resume_kernel)
 181         __cli
 182         mov     (TI_preempt_count,a2),d0        # non-zero preempt_count ?
 183         cmp     0,d0
 184         bne     restore_all
 185
 186 need_resched:
 187         btst    _TIF_NEED_RESCHED,(TI_flags,a2)
 188         beq     restore_all
 189         mov     (REG_EPSW,fp),d0
 190         and     EPSW_IM,d0
 191         cmp     EPSW_IM_7,d0            # interrupts off (exception path) ?
 192         bne     restore_all
 193         call    preempt_schedule_irq[],0
 194         jmp     need_resched
 195 #endif
 196
 197
 198 ###############################################################################
 199 #
 200 # IRQ handler entry point
 201 # - intended to be entered at multiple priorities
 202 #
 203 ###############################################################################
 204 ENTRY(irq_handler)
 205         add     -4,sp
 206         SAVE_ALL
 207
 208         # it's not a syscall
 209         mov     0xffffffff,d0
 210         mov     d0,(REG_ORIG_D0,fp)
 211
 212         mov     fp,d0
 213         call    do_IRQ[],0                      # do_IRQ(regs)
 214
 215         jmp     ret_from_intr
 216
 217 ###############################################################################
 218 #
 219 # Monitor Signal handler entry point
 220 #
 221 ###############################################################################
 222 ENTRY(monitor_signal)
 223         movbu   (0xae000001),d1
 224         cmp     1,d1
 225         beq     monsignal
 226         ret     [],0
 227
 228 monsignal:
 229         or      EPSW_NMID,epsw
 230         mov     d0,a0
 231         mov     a0,sp
 232         mov     (REG_EPSW,fp),d1
 233         and     ~EPSW_nSL,d1
 234         mov     d1,(REG_EPSW,fp)
 235         movm    (sp),[d2,d3,a2,a3,exreg0,exreg1,exother]
 236         mov     (sp),a1
 237         mov     a1,usp
 238         movm    (sp),[other]
 239         add     4,sp
 240 here:   jmp     0x8e000008-here+0x8e000008
 241
 242 ###############################################################################
 243 #
 244 # Double Fault handler entry point
 245 # - note that there will not be a stack, D0/A0 will hold EPSW/PC as were
 246 #
 247 ###############################################################################
 248         .section .bss
 249         .balign THREAD_SIZE
 250         .space  THREAD_SIZE
 251 __df_stack:
 252         .previous
 253
 254 ENTRY(double_fault)
 255         mov     a0,(__df_stack-4)       # PC as was
 256         mov     d0,(__df_stack-8)       # EPSW as was
 257         mn10300_set_dbfleds             # display 'db-f' on the LEDs
 258         mov     0xaa55aa55,d0
 259         mov     d0,(__df_stack-12)      # no ORIG_D0
 260         mov     sp,a0                   # save corrupted SP
 261         mov     __df_stack-12,sp        # emergency supervisor stack
 262         SAVE_ALL
 263         mov     a0,(REG_A0,fp)          # save corrupted SP as A0 (which got
 264                                         # clobbered by the CPU)
 265         mov     fp,d0
 266         calls   do_double_fault
 267 double_fault_loop:
 268         bra     double_fault_loop
 269
 270 ###############################################################################
 271 #
 272 # Bus Error handler entry point
 273 # - handle external (async) bus errors separately
 274 #
 275 ###############################################################################
 276 ENTRY(raw_bus_error)
 277         add     -4,sp
 278         mov     d0,(sp)
 279         mov     (BCBERR),d0             # what
 280         btst    BCBERR_BEMR_DMA,d0      # see if it was an external bus error
 281         beq     __common_exception_aux  # it wasn't
 282
 283         SAVE_ALL
 284         mov     (BCBEAR),d1             # destination of erroneous access
 285
 286         mov     (REG_ORIG_D0,fp),d2
 287         mov     d2,(REG_D0,fp)
 288         mov     -1,d2
 289         mov     d2,(REG_ORIG_D0,fp)
 290
 291         add     -4,sp
 292         mov     fp,(12,sp)              # frame pointer
 293         call    io_bus_error[],0
 294         jmp     restore_all
 295
 296 ###############################################################################
 297 #
 298 # Miscellaneous exception entry points
 299 #
 300 ###############################################################################
 301 ENTRY(nmi_handler)
 302         add     -4,sp
 303         mov     d0,(sp)
 304         mov     (TBR),d0
 305         bra     __common_exception_nonmi
 306
 307 ENTRY(__common_exception)
 308         add     -4,sp
 309         mov     d0,(sp)
 310
 311 __common_exception_aux:
 312         mov     (TBR),d0
 313         and     ~EPSW_NMID,epsw         # turn NMIs back on if not NMI
 314         or      EPSW_IE,epsw
 315
 316 __common_exception_nonmi:
 317         and     0x0000FFFF,d0           # turn the exception code into a vector
 318                                         # table index
 319
 320         btst    0x00000007,d0
 321         bne     1f
 322         cmp     0x00000400,d0
 323         bge     1f
 324
 325         SAVE_ALL                        # build the stack frame
 326
 327         mov     (REG_D0,fp),a2          # get the exception number
 328         mov     (REG_ORIG_D0,fp),d0
 329         mov     d0,(REG_D0,fp)
 330         mov     -1,d0
 331         mov     d0,(REG_ORIG_D0,fp)
 332
 333 #ifdef CONFIG_GDBSTUB
 334         btst    0x01,(gdbstub_busy)
 335         beq     2f
 336         and     ~EPSW_IE,epsw
 337         mov     fp,d0
 338         mov     a2,d1
 339         call    gdbstub_exception[],0   # gdbstub itself caused an exception
 340         bra     restore_all
 341 2:
 342 #endif
 343
 344         mov     fp,d0                   # arg 0: stacked register file
 345         mov     a2,d1                   # arg 1: exception number
 346         lsr     1,a2
 347
 348         mov     (exception_table,a2),a2
 349         calls   (a2)
 350         jmp     ret_from_exception
 351
 352 1:      pi                              # BUG() equivalent
 353
 354 ###############################################################################
 355 #
 356 # Exception handler functions table
 357 #
 358 ###############################################################################
 359         .data
 360 ENTRY(exception_table)
 361         .rept   0x400>>1
 362          .long  uninitialised_exception
 363         .endr
 364         .previous
 365
 366 ###############################################################################
 367 #
 368 # Change an entry in the exception table
 369 # - D0 exception code, D1 handler
 370 #
 371 ###############################################################################
 372 ENTRY(set_excp_vector)
 373         lsr     1,d0
 374         add     exception_table,d0
 375         mov     d1,(d0)
 376         mov     4,d1
 377 #if defined(CONFIG_MN10300_CACHE_WBACK)
 378         jmp     mn10300_dcache_flush_inv_range2
 379 #else
 380         ret     [],0
 381 #endif
 382
 383 ###############################################################################
 384 #
 385 # System call table
 386 #
 387 ###############################################################################
 388         .data
 389 ENTRY(sys_call_table)
 390         .long sys_restart_syscall       /* 0 */
 391         .long sys_exit
 392         .long sys_fork
 393         .long sys_read
 394         .long sys_write
 395         .long sys_open          /* 5 */
 396         .long sys_close
 397         .long sys_waitpid
 398         .long sys_creat
 399         .long sys_link
 400         .long sys_unlink        /* 10 */
 401         .long sys_execve
 402         .long sys_chdir
 403         .long sys_time
 404         .long sys_mknod
 405         .long sys_chmod         /* 15 */
 406         .long sys_lchown16
 407         .long sys_ni_syscall    /* old break syscall holder */
 408         .long sys_stat
 409         .long sys_lseek
 410         .long sys_getpid        /* 20 */
 411         .long sys_mount
 412         .long sys_oldumount
 413         .long sys_setuid16
 414         .long sys_getuid16
 415         .long sys_stime         /* 25 */
 416         .long sys_ptrace
 417         .long sys_alarm
 418         .long sys_fstat
 419         .long sys_pause
 420         .long sys_utime         /* 30 */
 421         .long sys_ni_syscall    /* old stty syscall holder */
 422         .long sys_ni_syscall    /* old gtty syscall holder */
 423         .long sys_access
 424         .long sys_nice
 425         .long sys_ni_syscall    /* 35 - old ftime syscall holder */
 426         .long sys_sync
 427         .long sys_kill
 428         .long sys_rename
 429         .long sys_mkdir
 430         .long sys_rmdir         /* 40 */
 431         .long sys_dup
 432         .long sys_pipe
 433         .long sys_times
 434         .long sys_ni_syscall    /* old prof syscall holder */
 435         .long sys_brk           /* 45 */
 436         .long sys_setgid16
 437         .long sys_getgid16
 438         .long sys_signal
 439         .long sys_geteuid16
 440         .long sys_getegid16     /* 50 */
 441         .long sys_acct
 442         .long sys_umount        /* recycled never used phys() */
 443         .long sys_ni_syscall    /* old lock syscall holder */
 444         .long sys_ioctl
 445         .long sys_fcntl         /* 55 */
 446         .long sys_ni_syscall    /* old mpx syscall holder */
 447         .long sys_setpgid
 448         .long sys_ni_syscall    /* old ulimit syscall holder */
 449         .long sys_ni_syscall    /* old sys_olduname */
 450         .long sys_umask         /* 60 */
 451         .long sys_chroot
 452         .long sys_ustat
 453         .long sys_dup2
 454         .long sys_getppid
 455         .long sys_getpgrp       /* 65 */
 456         .long sys_setsid
 457         .long sys_sigaction
 458         .long sys_sgetmask
 459         .long sys_ssetmask
 460         .long sys_setreuid16    /* 70 */
 461         .long sys_setregid16
 462         .long sys_sigsuspend
 463         .long sys_sigpending
 464         .long sys_sethostname
 465         .long sys_setrlimit     /* 75 */
 466         .long sys_old_getrlimit
 467         .long sys_getrusage
 468         .long sys_gettimeofday
 469         .long sys_settimeofday
 470         .long sys_getgroups16   /* 80 */
 471         .long sys_setgroups16
 472         .long sys_old_select
 473         .long sys_symlink
 474         .long sys_lstat
 475         .long sys_readlink      /* 85 */
 476         .long sys_uselib
 477         .long sys_swapon
 478         .long sys_reboot
 479         .long sys_old_readdir
 480         .long old_mmap          /* 90 */
 481         .long sys_munmap
 482         .long sys_truncate
 483         .long sys_ftruncate
 484         .long sys_fchmod
 485         .long sys_fchown16      /* 95 */
 486         .long sys_getpriority
 487         .long sys_setpriority
 488         .long sys_ni_syscall    /* old profil syscall holder */
 489         .long sys_statfs
 490         .long sys_fstatfs       /* 100 */
 491         .long sys_ni_syscall    /* ioperm */
 492         .long sys_socketcall
 493         .long sys_syslog
 494         .long sys_setitimer
 495         .long sys_getitimer     /* 105 */
 496         .long sys_newstat
 497         .long sys_newlstat
 498         .long sys_newfstat
 499         .long sys_ni_syscall    /* old sys_uname */
 500         .long sys_ni_syscall    /* 110 - iopl */
 501         .long sys_vhangup
 502         .long sys_ni_syscall    /* old "idle" system call */
 503         .long sys_ni_syscall    /* vm86old */
 504         .long sys_wait4
 505         .long sys_swapoff       /* 115 */
 506         .long sys_sysinfo
 507         .long sys_ipc
 508         .long sys_fsync
 509         .long sys_sigreturn
 510         .long sys_clone         /* 120 */
 511         .long sys_setdomainname
 512         .long sys_newuname
 513         .long sys_ni_syscall    /* modify_ldt */
 514         .long sys_adjtimex
 515         .long sys_mprotect      /* 125 */
 516         .long sys_sigprocmask
 517         .long sys_ni_syscall    /* old "create_module" */
 518         .long sys_init_module
 519         .long sys_delete_module
 520         .long sys_ni_syscall    /* 130: old "get_kernel_syms" */
 521         .long sys_quotactl
 522         .long sys_getpgid
 523         .long sys_fchdir
 524         .long sys_bdflush
 525         .long sys_sysfs         /* 135 */
 526         .long sys_personality
 527         .long sys_ni_syscall    /* reserved for afs_syscall */
 528         .long sys_setfsuid16
 529         .long sys_setfsgid16
 530         .long sys_llseek        /* 140 */
 531         .long sys_getdents
 532         .long sys_select
 533         .long sys_flock
 534         .long sys_msync
 535         .long sys_readv         /* 145 */
 536         .long sys_writev
 537         .long sys_getsid
 538         .long sys_fdatasync
 539         .long sys_sysctl
 540         .long sys_mlock         /* 150 */
 541         .long sys_munlock
 542         .long sys_mlockall
 543         .long sys_munlockall
 544         .long sys_sched_setparam
 545         .long sys_sched_getparam   /* 155 */
 546         .long sys_sched_setscheduler
 547         .long sys_sched_getscheduler
 548         .long sys_sched_yield
 549         .long sys_sched_get_priority_max
 550         .long sys_sched_get_priority_min  /* 160 */
 551         .long sys_sched_rr_get_interval
 552         .long sys_nanosleep
 553         .long sys_mremap
 554         .long sys_setresuid16
 555         .long sys_getresuid16   /* 165 */
 556         .long sys_ni_syscall    /* vm86 */
 557         .long sys_ni_syscall    /* Old sys_query_module */
 558         .long sys_poll
 559         .long sys_nfsservctl
 560         .long sys_setresgid16   /* 170 */
 561         .long sys_getresgid16
 562         .long sys_prctl
 563         .long sys_rt_sigreturn
 564         .long sys_rt_sigaction
 565         .long sys_rt_sigprocmask        /* 175 */
 566         .long sys_rt_sigpending
 567         .long sys_rt_sigtimedwait
 568         .long sys_rt_sigqueueinfo
 569         .long sys_rt_sigsuspend
 570         .long sys_pread64       /* 180 */
 571         .long sys_pwrite64
 572         .long sys_chown16
 573         .long sys_getcwd
 574         .long sys_capget
 575         .long sys_capset        /* 185 */
 576         .long sys_sigaltstack
 577         .long sys_sendfile
 578         .long sys_ni_syscall    /* reserved for streams1 */
 579         .long sys_ni_syscall    /* reserved for streams2 */
 580         .long sys_vfork         /* 190 */
 581         .long sys_getrlimit
 582         .long sys_mmap_pgoff
 583         .long sys_truncate64
 584         .long sys_ftruncate64
 585         .long sys_stat64        /* 195 */
 586         .long sys_lstat64
 587         .long sys_fstat64
 588         .long sys_lchown
 589         .long sys_getuid
 590         .long sys_getgid        /* 200 */
 591         .long sys_geteuid
 592         .long sys_getegid
 593         .long sys_setreuid
 594         .long sys_setregid
 595         .long sys_getgroups     /* 205 */
 596         .long sys_setgroups
 597         .long sys_fchown
 598         .long sys_setresuid
 599         .long sys_getresuid
 600         .long sys_setresgid     /* 210 */
 601         .long sys_getresgid
 602         .long sys_chown
 603         .long sys_setuid
 604         .long sys_setgid
 605         .long sys_setfsuid      /* 215 */
 606         .long sys_setfsgid
 607         .long sys_pivot_root
 608         .long sys_mincore
 609         .long sys_madvise
 610         .long sys_getdents64    /* 220 */
 611         .long sys_fcntl64
 612         .long sys_ni_syscall    /* reserved for TUX */
 613         .long sys_ni_syscall
 614         .long sys_gettid
 615         .long sys_readahead     /* 225 */
 616         .long sys_setxattr
 617         .long sys_lsetxattr
 618         .long sys_fsetxattr
 619         .long sys_getxattr
 620         .long sys_lgetxattr     /* 230 */
 621         .long sys_fgetxattr
 622         .long sys_listxattr
 623         .long sys_llistxattr
 624         .long sys_flistxattr
 625         .long sys_removexattr   /* 235 */
 626         .long sys_lremovexattr
 627         .long sys_fremovexattr
 628         .long sys_tkill
 629         .long sys_sendfile64
 630         .long sys_futex         /* 240 */
 631         .long sys_sched_setaffinity
 632         .long sys_sched_getaffinity
 633         .long sys_ni_syscall    /* sys_set_thread_area */
 634         .long sys_ni_syscall    /* sys_get_thread_area */
 635         .long sys_io_setup      /* 245 */
 636         .long sys_io_destroy
 637         .long sys_io_getevents
 638         .long sys_io_submit
 639         .long sys_io_cancel
 640         .long sys_fadvise64     /* 250 */
 641         .long sys_ni_syscall
 642         .long sys_exit_group
 643         .long sys_lookup_dcookie
 644         .long sys_epoll_create
 645         .long sys_epoll_ctl     /* 255 */
 646         .long sys_epoll_wait
 647         .long sys_remap_file_pages
 648         .long sys_set_tid_address
 649         .long sys_timer_create
 650         .long sys_timer_settime         /* 260 */
 651         .long sys_timer_gettime
 652         .long sys_timer_getoverrun
 653         .long sys_timer_delete
 654         .long sys_clock_settime
 655         .long sys_clock_gettime         /* 265 */
 656         .long sys_clock_getres
 657         .long sys_clock_nanosleep
 658         .long sys_statfs64
 659         .long sys_fstatfs64
 660         .long sys_tgkill                /* 270 */
 661         .long sys_utimes
 662         .long sys_fadvise64_64
 663         .long sys_ni_syscall    /* sys_vserver */
 664         .long sys_mbind
 665         .long sys_get_mempolicy         /* 275 */
 666         .long sys_set_mempolicy
 667         .long sys_mq_open
 668         .long sys_mq_unlink
 669         .long sys_mq_timedsend
 670         .long sys_mq_timedreceive       /* 280 */
 671         .long sys_mq_notify
 672         .long sys_mq_getsetattr
 673         .long sys_kexec_load
 674         .long sys_waitid
 675         .long sys_ni_syscall            /* 285 */ /* available */
 676         .long sys_add_key
 677         .long sys_request_key
 678         .long sys_keyctl
 679         .long sys_cacheflush
 680         .long sys_ioprio_set            /* 290 */
 681         .long sys_ioprio_get
 682         .long sys_inotify_init
 683         .long sys_inotify_add_watch
 684         .long sys_inotify_rm_watch
 685         .long sys_migrate_pages         /* 295 */
 686         .long sys_openat
 687         .long sys_mkdirat
 688         .long sys_mknodat
 689         .long sys_fchownat
 690         .long sys_futimesat             /* 300 */
 691         .long sys_fstatat64
 692         .long sys_unlinkat
 693         .long sys_renameat
 694         .long sys_linkat
 695         .long sys_symlinkat             /* 305 */
 696         .long sys_readlinkat
 697         .long sys_fchmodat
 698         .long sys_faccessat
 699         .long sys_pselect6
 700         .long sys_ppoll                 /* 310 */
 701         .long sys_unshare
 702         .long sys_set_robust_list
 703         .long sys_get_robust_list
 704         .long sys_splice
 705         .long sys_sync_file_range       /* 315 */
 706         .long sys_tee
 707         .long sys_vmsplice
 708         .long sys_move_pages
 709         .long sys_getcpu
 710         .long sys_epoll_pwait           /* 320 */
 711         .long sys_utimensat
 712         .long sys_signalfd
 713         .long sys_timerfd_create
 714         .long sys_eventfd
 715         .long sys_fallocate             /* 325 */
 716         .long sys_timerfd_settime
 717         .long sys_timerfd_gettime
 718         .long sys_signalfd4
 719         .long sys_eventfd2
 720         .long sys_epoll_create1         /* 330 */
 721         .long sys_dup3
 722         .long sys_pipe2
 723         .long sys_inotify_init1
 724         .long sys_preadv
 725         .long sys_pwritev               /* 335 */
 726         .long sys_rt_tgsigqueueinfo
 727         .long sys_perf_event_open
 728         .long sys_recvmmsg
 729
 730
 731 nr_syscalls=(.-sys_call_table)/4