arch/mips/kernel/scall32-o32.S

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1995-99, 2000- 02, 06 Ralf Baechle <ralf@linux-mips.org>
   7  * Copyright (C) 2001 MIPS Technologies, Inc.
   8  * Copyright (C) 2004 Thiemo Seufer
   9  * Copyright (C) 2014 Imagination Technologies Ltd.
  10  */
  11 #include <linux/errno.h>
  12 #include <asm/asm.h>
  13 #include <asm/asmmacro.h>
  14 #include <asm/irqflags.h>
  15 #include <asm/mipsregs.h>
  16 #include <asm/regdef.h>
  17 #include <asm/stackframe.h>
  18 #include <asm/isadep.h>
  19 #include <asm/sysmips.h>
  20 #include <asm/thread_info.h>
  21 #include <asm/unistd.h>
  22 #include <asm/war.h>
  23 #include <asm/asm-offsets.h>
  24
  25 /* Highest syscall used of any syscall flavour */
  26 #define MAX_SYSCALL_NO  __NR_O32_Linux + __NR_O32_Linux_syscalls
  27
  28         .align  5
  29 NESTED(handle_sys, PT_SIZE, sp)
  30         .set    noat
  31         SAVE_SOME
  32         TRACE_IRQS_ON_RELOAD
  33         STI
  34         .set    at
  35
  36         lw      t1, PT_EPC(sp)          # skip syscall on return
  37
  38         subu    v0, v0, __NR_O32_Linux  # check syscall number
  39         addiu   t1, 4                   # skip to next instruction
  40         sw      t1, PT_EPC(sp)
  41
  42         sw      a3, PT_R26(sp)          # save a3 for syscall restarting
  43
  44         /*
  45          * More than four arguments.  Try to deal with it by copying the
  46          * stack arguments from the user stack to the kernel stack.
  47          * This Sucks (TM).
  48          */
  49         lw      t0, PT_R29(sp)          # get old user stack pointer
  50
  51         /*
  52          * We intentionally keep the kernel stack a little below the top of
  53          * userspace so we don't have to do a slower byte accurate check here.
  54          */
  55         lw      t5, TI_ADDR_LIMIT($28)
  56         addu    t4, t0, 32
  57         and     t5, t4
  58         bltz    t5, bad_stack           # -> sp is bad
  59
  60         /*
  61          * Ok, copy the args from the luser stack to the kernel stack.
  62          */
  63
  64         .set    push
  65         .set    noreorder
  66         .set    nomacro
  67
  68 load_a4: user_lw(t5, 16(t0))            # argument #5 from usp
  69 load_a5: user_lw(t6, 20(t0))            # argument #6 from usp
  70 load_a6: user_lw(t7, 24(t0))            # argument #7 from usp
  71 load_a7: user_lw(t8, 28(t0))            # argument #8 from usp
  72 loads_done:
  73
  74         sw      t5, 16(sp)              # argument #5 to ksp
  75         sw      t6, 20(sp)              # argument #6 to ksp
  76         sw      t7, 24(sp)              # argument #7 to ksp
  77         sw      t8, 28(sp)              # argument #8 to ksp
  78         .set    pop
  79
  80         .section __ex_table,"a"
  81         PTR     load_a4, bad_stack_a4
  82         PTR     load_a5, bad_stack_a5
  83         PTR     load_a6, bad_stack_a6
  84         PTR     load_a7, bad_stack_a7
  85         .previous
  86
  87         lw      t0, TI_FLAGS($28)       # syscall tracing enabled?
  88         li      t1, _TIF_WORK_SYSCALL_ENTRY
  89         and     t0, t1
  90         bnez    t0, syscall_trace_entry # -> yes
  91 syscall_common:
  92         sltiu   t0, v0, __NR_O32_Linux_syscalls + 1
  93         beqz    t0, illegal_syscall
  94
  95         sll     t0, v0, 2
  96         la      t1, sys_call_table
  97         addu    t1, t0
  98         lw      t2, (t1)                # syscall routine
  99
 100         beqz    t2, illegal_syscall
 101
 102         jalr    t2                      # Do The Real Thing (TM)
 103
 104         li      t0, -EMAXERRNO - 1      # error?
 105         sltu    t0, t0, v0
 106         sw      t0, PT_R7(sp)           # set error flag
 107         beqz    t0, 1f
 108
 109         lw      t1, PT_R2(sp)           # syscall number
 110         negu    v0                      # error
 111         sw      t1, PT_R0(sp)           # save it for syscall restarting
 112 1:      sw      v0, PT_R2(sp)           # result
 113
 114 o32_syscall_exit:
 115         j       syscall_exit_partial
 116
 117 /* ------------------------------------------------------------------------ */
 118
 119 syscall_trace_entry:
 120         SAVE_STATIC
 121         move    s0, v0
 122         move    a0, sp
 123
 124         /*
 125          * syscall number is in v0 unless we called syscall(__NR_###)
 126          * where the real syscall number is in a0
 127          */
 128         addiu   a1, v0,  __NR_O32_Linux
 129         bnez    v0, 1f /* __NR_syscall at offset 0 */
 130         lw      a1, PT_R4(sp)
 131
 132 1:      jal     syscall_trace_enter
 133
 134         bltz    v0, 1f                  # seccomp failed? Skip syscall
 135
 136         move    v0, s0                  # restore syscall
 137
 138         RESTORE_STATIC
 139         lw      a0, PT_R4(sp)           # Restore argument registers
 140         lw      a1, PT_R5(sp)
 141         lw      a2, PT_R6(sp)
 142         lw      a3, PT_R7(sp)
 143         j       syscall_common
 144
 145 1:      j       syscall_exit
 146
 147 /* ------------------------------------------------------------------------ */
 148
 149         /*
 150          * Our open-coded access area sanity test for the stack pointer
 151          * failed. We probably should handle this case a bit more drastic.
 152          */
 153 bad_stack:
 154         li      v0, EFAULT
 155         sw      v0, PT_R2(sp)
 156         li      t0, 1                           # set error flag
 157         sw      t0, PT_R7(sp)
 158         j       o32_syscall_exit
 159
 160 bad_stack_a4:
 161         li      t5, 0
 162         b       load_a5
 163
 164 bad_stack_a5:
 165         li      t6, 0
 166         b       load_a6
 167
 168 bad_stack_a6:
 169         li      t7, 0
 170         b       load_a7
 171
 172 bad_stack_a7:
 173         li      t8, 0
 174         b       loads_done
 175
 176         /*
 177          * The system call does not exist in this kernel
 178          */
 179 illegal_syscall:
 180         li      v0, ENOSYS                      # error
 181         sw      v0, PT_R2(sp)
 182         li      t0, 1                           # set error flag
 183         sw      t0, PT_R7(sp)
 184         j       o32_syscall_exit
 185         END(handle_sys)
 186
 187         LEAF(sys_syscall)
 188         subu    t0, a0, __NR_O32_Linux  # check syscall number
 189         sltiu   v0, t0, __NR_O32_Linux_syscalls + 1
 190         beqz    t0, einval              # do not recurse
 191         sll     t1, t0, 2
 192         beqz    v0, einval
 193         lw      t2, sys_call_table(t1)          # syscall routine
 194         sw      a0, PT_R2(sp)                   # call routine directly on restart
 195
 196         /* Some syscalls like execve get their arguments from struct pt_regs
 197            and claim zero arguments in the syscall table. Thus we have to
 198            assume the worst case and shuffle around all potential arguments.
 199            If you want performance, don't use indirect syscalls. */
 200
 201         move    a0, a1                          # shift argument registers
 202         move    a1, a2
 203         move    a2, a3
 204         lw      a3, 16(sp)
 205         lw      t4, 20(sp)
 206         lw      t5, 24(sp)
 207         lw      t6, 28(sp)
 208         sw      t4, 16(sp)
 209         sw      t5, 20(sp)
 210         sw      t6, 24(sp)
 211         sw      a0, PT_R4(sp)                   # .. and push back a0 - a3, some
 212         sw      a1, PT_R5(sp)                   # syscalls expect them there
 213         sw      a2, PT_R6(sp)
 214         sw      a3, PT_R7(sp)
 215         sw      a3, PT_R26(sp)                  # update a3 for syscall restarting
 216         jr      t2
 217         /* Unreached */
 218
 219 einval: li      v0, -ENOSYS
 220         jr      ra
 221         END(sys_syscall)
 222
 223         .align  2
 224         .type   sys_call_table, @object
 225 EXPORT(sys_call_table)
 226         PTR     sys_syscall                     /* 4000 */
 227         PTR     sys_exit
 228         PTR     __sys_fork
 229         PTR     sys_read
 230         PTR     sys_write
 231         PTR     sys_open                        /* 4005 */
 232         PTR     sys_close
 233         PTR     sys_waitpid
 234         PTR     sys_creat
 235         PTR     sys_link
 236         PTR     sys_unlink                      /* 4010 */
 237         PTR     sys_execve
 238         PTR     sys_chdir
 239         PTR     sys_time
 240         PTR     sys_mknod
 241         PTR     sys_chmod                       /* 4015 */
 242         PTR     sys_lchown
 243         PTR     sys_ni_syscall
 244         PTR     sys_ni_syscall                  /* was sys_stat */
 245         PTR     sys_lseek
 246         PTR     sys_getpid                      /* 4020 */
 247         PTR     sys_mount
 248         PTR     sys_oldumount
 249         PTR     sys_setuid
 250         PTR     sys_getuid
 251         PTR     sys_stime                       /* 4025 */
 252         PTR     sys_ptrace
 253         PTR     sys_alarm
 254         PTR     sys_ni_syscall                  /* was sys_fstat */
 255         PTR     sys_pause
 256         PTR     sys_utime                       /* 4030 */
 257         PTR     sys_ni_syscall
 258         PTR     sys_ni_syscall
 259         PTR     sys_access
 260         PTR     sys_nice
 261         PTR     sys_ni_syscall                  /* 4035 */
 262         PTR     sys_sync
 263         PTR     sys_kill
 264         PTR     sys_rename
 265         PTR     sys_mkdir
 266         PTR     sys_rmdir                       /* 4040 */
 267         PTR     sys_dup
 268         PTR     sysm_pipe
 269         PTR     sys_times
 270         PTR     sys_ni_syscall
 271         PTR     sys_brk                         /* 4045 */
 272         PTR     sys_setgid
 273         PTR     sys_getgid
 274         PTR     sys_ni_syscall                  /* was signal(2) */
 275         PTR     sys_geteuid
 276         PTR     sys_getegid                     /* 4050 */
 277         PTR     sys_acct
 278         PTR     sys_umount
 279         PTR     sys_ni_syscall
 280         PTR     sys_ioctl
 281         PTR     sys_fcntl                       /* 4055 */
 282         PTR     sys_ni_syscall
 283         PTR     sys_setpgid
 284         PTR     sys_ni_syscall
 285         PTR     sys_olduname
 286         PTR     sys_umask                       /* 4060 */
 287         PTR     sys_chroot
 288         PTR     sys_ustat
 289         PTR     sys_dup2
 290         PTR     sys_getppid
 291         PTR     sys_getpgrp                     /* 4065 */
 292         PTR     sys_setsid
 293         PTR     sys_sigaction
 294         PTR     sys_sgetmask
 295         PTR     sys_ssetmask
 296         PTR     sys_setreuid                    /* 4070 */
 297         PTR     sys_setregid
 298         PTR     sys_sigsuspend
 299         PTR     sys_sigpending
 300         PTR     sys_sethostname
 301         PTR     sys_setrlimit                   /* 4075 */
 302         PTR     sys_getrlimit
 303         PTR     sys_getrusage
 304         PTR     sys_gettimeofday
 305         PTR     sys_settimeofday
 306         PTR     sys_getgroups                   /* 4080 */
 307         PTR     sys_setgroups
 308         PTR     sys_ni_syscall                  /* old_select */
 309         PTR     sys_symlink
 310         PTR     sys_ni_syscall                  /* was sys_lstat */
 311         PTR     sys_readlink                    /* 4085 */
 312         PTR     sys_uselib
 313         PTR     sys_swapon
 314         PTR     sys_reboot
 315         PTR     sys_old_readdir
 316         PTR     sys_mips_mmap                   /* 4090 */
 317         PTR     sys_munmap
 318         PTR     sys_truncate
 319         PTR     sys_ftruncate
 320         PTR     sys_fchmod
 321         PTR     sys_fchown                      /* 4095 */
 322         PTR     sys_getpriority
 323         PTR     sys_setpriority
 324         PTR     sys_ni_syscall
 325         PTR     sys_statfs
 326         PTR     sys_fstatfs                     /* 4100 */
 327         PTR     sys_ni_syscall                  /* was ioperm(2) */
 328         PTR     sys_socketcall
 329         PTR     sys_syslog
 330         PTR     sys_setitimer
 331         PTR     sys_getitimer                   /* 4105 */
 332         PTR     sys_newstat
 333         PTR     sys_newlstat
 334         PTR     sys_newfstat
 335         PTR     sys_uname
 336         PTR     sys_ni_syscall                  /* 4110 was iopl(2) */
 337         PTR     sys_vhangup
 338         PTR     sys_ni_syscall                  /* was sys_idle() */
 339         PTR     sys_ni_syscall                  /* was sys_vm86 */
 340         PTR     sys_wait4
 341         PTR     sys_swapoff                     /* 4115 */
 342         PTR     sys_sysinfo
 343         PTR     sys_ipc
 344         PTR     sys_fsync
 345         PTR     sys_sigreturn
 346         PTR     __sys_clone                     /* 4120 */
 347         PTR     sys_setdomainname
 348         PTR     sys_newuname
 349         PTR     sys_ni_syscall                  /* sys_modify_ldt */
 350         PTR     sys_adjtimex
 351         PTR     sys_mprotect                    /* 4125 */
 352         PTR     sys_sigprocmask
 353         PTR     sys_ni_syscall                  /* was create_module */
 354         PTR     sys_init_module
 355         PTR     sys_delete_module
 356         PTR     sys_ni_syscall                  /* 4130 was get_kernel_syms */
 357         PTR     sys_quotactl
 358         PTR     sys_getpgid
 359         PTR     sys_fchdir
 360         PTR     sys_bdflush
 361         PTR     sys_sysfs                       /* 4135 */
 362         PTR     sys_personality
 363         PTR     sys_ni_syscall                  /* for afs_syscall */
 364         PTR     sys_setfsuid
 365         PTR     sys_setfsgid
 366         PTR     sys_llseek                      /* 4140 */
 367         PTR     sys_getdents
 368         PTR     sys_select
 369         PTR     sys_flock
 370         PTR     sys_msync
 371         PTR     sys_readv                       /* 4145 */
 372         PTR     sys_writev
 373         PTR     sys_cacheflush
 374         PTR     sys_cachectl
 375         PTR     sys_sysmips
 376         PTR     sys_ni_syscall                  /* 4150 */
 377         PTR     sys_getsid
 378         PTR     sys_fdatasync
 379         PTR     sys_sysctl
 380         PTR     sys_mlock
 381         PTR     sys_munlock                     /* 4155 */
 382         PTR     sys_mlockall
 383         PTR     sys_munlockall
 384         PTR     sys_sched_setparam
 385         PTR     sys_sched_getparam
 386         PTR     sys_sched_setscheduler          /* 4160 */
 387         PTR     sys_sched_getscheduler
 388         PTR     sys_sched_yield
 389         PTR     sys_sched_get_priority_max
 390         PTR     sys_sched_get_priority_min
 391         PTR     sys_sched_rr_get_interval       /* 4165 */
 392         PTR     sys_nanosleep
 393         PTR     sys_mremap
 394         PTR     sys_accept
 395         PTR     sys_bind
 396         PTR     sys_connect                     /* 4170 */
 397         PTR     sys_getpeername
 398         PTR     sys_getsockname
 399         PTR     sys_getsockopt
 400         PTR     sys_listen
 401         PTR     sys_recv                        /* 4175 */
 402         PTR     sys_recvfrom
 403         PTR     sys_recvmsg
 404         PTR     sys_send
 405         PTR     sys_sendmsg
 406         PTR     sys_sendto                      /* 4180 */
 407         PTR     sys_setsockopt
 408         PTR     sys_shutdown
 409         PTR     sys_socket
 410         PTR     sys_socketpair
 411         PTR     sys_setresuid                   /* 4185 */
 412         PTR     sys_getresuid
 413         PTR     sys_ni_syscall                  /* was sys_query_module */
 414         PTR     sys_poll
 415         PTR     sys_ni_syscall                  /* was nfsservctl */
 416         PTR     sys_setresgid                   /* 4190 */
 417         PTR     sys_getresgid
 418         PTR     sys_prctl
 419         PTR     sys_rt_sigreturn
 420         PTR     sys_rt_sigaction
 421         PTR     sys_rt_sigprocmask              /* 4195 */
 422         PTR     sys_rt_sigpending
 423         PTR     sys_rt_sigtimedwait
 424         PTR     sys_rt_sigqueueinfo
 425         PTR     sys_rt_sigsuspend
 426         PTR     sys_pread64                     /* 4200 */
 427         PTR     sys_pwrite64
 428         PTR     sys_chown
 429         PTR     sys_getcwd
 430         PTR     sys_capget
 431         PTR     sys_capset                      /* 4205 */
 432         PTR     sys_sigaltstack
 433         PTR     sys_sendfile
 434         PTR     sys_ni_syscall
 435         PTR     sys_ni_syscall
 436         PTR     sys_mips_mmap2                  /* 4210 */
 437         PTR     sys_truncate64
 438         PTR     sys_ftruncate64
 439         PTR     sys_stat64
 440         PTR     sys_lstat64
 441         PTR     sys_fstat64                     /* 4215 */
 442         PTR     sys_pivot_root
 443         PTR     sys_mincore
 444         PTR     sys_madvise
 445         PTR     sys_getdents64
 446         PTR     sys_fcntl64                     /* 4220 */
 447         PTR     sys_ni_syscall
 448         PTR     sys_gettid
 449         PTR     sys_readahead
 450         PTR     sys_setxattr
 451         PTR     sys_lsetxattr                   /* 4225 */
 452         PTR     sys_fsetxattr
 453         PTR     sys_getxattr
 454         PTR     sys_lgetxattr
 455         PTR     sys_fgetxattr
 456         PTR     sys_listxattr                   /* 4230 */
 457         PTR     sys_llistxattr
 458         PTR     sys_flistxattr
 459         PTR     sys_removexattr
 460         PTR     sys_lremovexattr
 461         PTR     sys_fremovexattr                /* 4235 */
 462         PTR     sys_tkill
 463         PTR     sys_sendfile64
 464         PTR     sys_futex
 465 #ifdef CONFIG_MIPS_MT_FPAFF
 466         /*
 467          * For FPU affinity scheduling on MIPS MT processors, we need to
 468          * intercept sys_sched_xxxaffinity() calls until we get a proper hook
 469          * in kernel/sched/core.c.  Considered only temporary we only support
 470          * these hooks for the 32-bit kernel - there is no MIPS64 MT processor
 471          * atm.
 472          */
 473         PTR     mipsmt_sys_sched_setaffinity
 474         PTR     mipsmt_sys_sched_getaffinity
 475 #else
 476         PTR     sys_sched_setaffinity
 477         PTR     sys_sched_getaffinity           /* 4240 */
 478 #endif /* CONFIG_MIPS_MT_FPAFF */
 479         PTR     sys_io_setup
 480         PTR     sys_io_destroy
 481         PTR     sys_io_getevents
 482         PTR     sys_io_submit
 483         PTR     sys_io_cancel                   /* 4245 */
 484         PTR     sys_exit_group
 485         PTR     sys_lookup_dcookie
 486         PTR     sys_epoll_create
 487         PTR     sys_epoll_ctl
 488         PTR     sys_epoll_wait                  /* 4250 */
 489         PTR     sys_remap_file_pages
 490         PTR     sys_set_tid_address
 491         PTR     sys_restart_syscall
 492         PTR     sys_fadvise64_64
 493         PTR     sys_statfs64                    /* 4255 */
 494         PTR     sys_fstatfs64
 495         PTR     sys_timer_create
 496         PTR     sys_timer_settime
 497         PTR     sys_timer_gettime
 498         PTR     sys_timer_getoverrun            /* 4260 */
 499         PTR     sys_timer_delete
 500         PTR     sys_clock_settime
 501         PTR     sys_clock_gettime
 502         PTR     sys_clock_getres
 503         PTR     sys_clock_nanosleep             /* 4265 */
 504         PTR     sys_tgkill
 505         PTR     sys_utimes
 506         PTR     sys_mbind
 507         PTR     sys_get_mempolicy
 508         PTR     sys_set_mempolicy               /* 4270 */
 509         PTR     sys_mq_open
 510         PTR     sys_mq_unlink
 511         PTR     sys_mq_timedsend
 512         PTR     sys_mq_timedreceive
 513         PTR     sys_mq_notify                   /* 4275 */
 514         PTR     sys_mq_getsetattr
 515         PTR     sys_ni_syscall                  /* sys_vserver */
 516         PTR     sys_waitid
 517         PTR     sys_ni_syscall                  /* available, was setaltroot */
 518         PTR     sys_add_key                     /* 4280 */
 519         PTR     sys_request_key
 520         PTR     sys_keyctl
 521         PTR     sys_set_thread_area
 522         PTR     sys_inotify_init
 523         PTR     sys_inotify_add_watch           /* 4285 */
 524         PTR     sys_inotify_rm_watch
 525         PTR     sys_migrate_pages
 526         PTR     sys_openat
 527         PTR     sys_mkdirat
 528         PTR     sys_mknodat                     /* 4290 */
 529         PTR     sys_fchownat
 530         PTR     sys_futimesat
 531         PTR     sys_fstatat64
 532         PTR     sys_unlinkat
 533         PTR     sys_renameat                    /* 4295 */
 534         PTR     sys_linkat
 535         PTR     sys_symlinkat
 536         PTR     sys_readlinkat
 537         PTR     sys_fchmodat
 538         PTR     sys_faccessat                   /* 4300 */
 539         PTR     sys_pselect6
 540         PTR     sys_ppoll
 541         PTR     sys_unshare
 542         PTR     sys_splice
 543         PTR     sys_sync_file_range             /* 4305 */
 544         PTR     sys_tee
 545         PTR     sys_vmsplice
 546         PTR     sys_move_pages
 547         PTR     sys_set_robust_list
 548         PTR     sys_get_robust_list             /* 4310 */
 549         PTR     sys_kexec_load
 550         PTR     sys_getcpu
 551         PTR     sys_epoll_pwait
 552         PTR     sys_ioprio_set
 553         PTR     sys_ioprio_get                  /* 4315 */
 554         PTR     sys_utimensat
 555         PTR     sys_signalfd
 556         PTR     sys_ni_syscall                  /* was timerfd */
 557         PTR     sys_eventfd
 558         PTR     sys_fallocate                   /* 4320 */
 559         PTR     sys_timerfd_create
 560         PTR     sys_timerfd_gettime
 561         PTR     sys_timerfd_settime
 562         PTR     sys_signalfd4
 563         PTR     sys_eventfd2                    /* 4325 */
 564         PTR     sys_epoll_create1
 565         PTR     sys_dup3
 566         PTR     sys_pipe2
 567         PTR     sys_inotify_init1
 568         PTR     sys_preadv                      /* 4330 */
 569         PTR     sys_pwritev
 570         PTR     sys_rt_tgsigqueueinfo
 571         PTR     sys_perf_event_open
 572         PTR     sys_accept4
 573         PTR     sys_recvmmsg                    /* 4335 */
 574         PTR     sys_fanotify_init
 575         PTR     sys_fanotify_mark
 576         PTR     sys_prlimit64
 577         PTR     sys_name_to_handle_at
 578         PTR     sys_open_by_handle_at           /* 4340 */
 579         PTR     sys_clock_adjtime
 580         PTR     sys_syncfs
 581         PTR     sys_sendmmsg
 582         PTR     sys_setns
 583         PTR     sys_process_vm_readv            /* 4345 */
 584         PTR     sys_process_vm_writev
 585         PTR     sys_kcmp
 586         PTR     sys_finit_module
 587         PTR     sys_sched_setattr
 588         PTR     sys_sched_getattr               /* 4350 */
 589         PTR     sys_renameat2
 590         PTR     sys_seccomp
 591         PTR     sys_getrandom
 592         PTR     sys_memfd_create
 593         PTR     sys_bpf                         /* 4355 */
 594         PTR     sys_execveat
 595         PTR     sys_userfaultfd
 596         PTR     sys_membarrier
 597         PTR     sys_mlock2
 598         PTR     sys_copy_file_range             /* 4360 */