Re: [PATCH v3 08/13] or1k: Linux Syscall Interface

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

Some comments below.

On 10/12/2021 20:34, Stafford Horne via Libc-alpha wrote:
> ---
>  sysdeps/unix/sysv/linux/or1k/arch-syscall.h   | 325 ++++++++++++++++++
>  sysdeps/unix/sysv/linux/or1k/bits/timesize.h  |  19 +
>  sysdeps/unix/sysv/linux/or1k/clone.c          |  61 ++++
>  sysdeps/unix/sysv/linux/or1k/jmp_buf-macros.h |  41 +++
>  sysdeps/unix/sysv/linux/or1k/mmap_internal.h  |  28 ++
>  sysdeps/unix/sysv/linux/or1k/or1k_clone.S     |  89 +++++
>  sysdeps/unix/sysv/linux/or1k/sysdep.c         |  34 ++
>  sysdeps/unix/sysv/linux/or1k/sysdep.h         | 201 +++++++++++
>  8 files changed, 798 insertions(+)
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/arch-syscall.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/bits/timesize.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/clone.c
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/jmp_buf-macros.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/mmap_internal.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/or1k_clone.S
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/sysdep.c
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/sysdep.h
> 
> diff --git a/sysdeps/unix/sysv/linux/or1k/arch-syscall.h b/sysdeps/unix/sysv/linux/or1k/arch-syscall.h
> new file mode 100644
> index 0000000000..c6c3556137
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/arch-syscall.h
> @@ -0,0 +1,325 @@
> +/* AUTOGENERATED by update-syscall-lists.py.  */
> +#define __NR_accept 202
> +#define __NR_accept4 242
> +#define __NR_acct 89
> +#define __NR_add_key 217
> +#define __NR_adjtimex 171
> +#define __NR_bind 200
> +#define __NR_bpf 280
> +#define __NR_brk 214
> +#define __NR_capget 90
> +#define __NR_capset 91
> +#define __NR_chdir 49
> +#define __NR_chroot 51
> +#define __NR_clock_adjtime 266
> +#define __NR_clock_adjtime64 405
> +#define __NR_clock_getres 114
> +#define __NR_clock_getres_time64 406
> +#define __NR_clock_gettime 113
> +#define __NR_clock_gettime64 403
> +#define __NR_clock_nanosleep 115
> +#define __NR_clock_nanosleep_time64 407
> +#define __NR_clock_settime 112
> +#define __NR_clock_settime64 404
> +#define __NR_clone 220
> +#define __NR_clone3 435
> +#define __NR_close 57
> +#define __NR_close_range 436
> +#define __NR_connect 203
> +#define __NR_copy_file_range 285
> +#define __NR_delete_module 106
> +#define __NR_dup 23
> +#define __NR_dup3 24
> +#define __NR_epoll_create1 20
> +#define __NR_epoll_ctl 21
> +#define __NR_epoll_pwait 22
> +#define __NR_epoll_pwait2 441
> +#define __NR_eventfd2 19
> +#define __NR_execve 221
> +#define __NR_execveat 281
> +#define __NR_exit 93
> +#define __NR_exit_group 94
> +#define __NR_faccessat 48
> +#define __NR_faccessat2 439
> +#define __NR_fadvise64_64 223
> +#define __NR_fallocate 47
> +#define __NR_fanotify_init 262
> +#define __NR_fanotify_mark 263
> +#define __NR_fchdir 50
> +#define __NR_fchmod 52
> +#define __NR_fchmodat 53
> +#define __NR_fchown 55
> +#define __NR_fchownat 54
> +#define __NR_fcntl64 25
> +#define __NR_fdatasync 83
> +#define __NR_fgetxattr 10
> +#define __NR_finit_module 273
> +#define __NR_flistxattr 13
> +#define __NR_flock 32
> +#define __NR_fremovexattr 16
> +#define __NR_fsconfig 431
> +#define __NR_fsetxattr 7
> +#define __NR_fsmount 432
> +#define __NR_fsopen 430
> +#define __NR_fspick 433
> +#define __NR_fstat64 80
> +#define __NR_fstatat64 79
> +#define __NR_fstatfs64 44
> +#define __NR_fsync 82
> +#define __NR_ftruncate64 46
> +#define __NR_futex 98
> +#define __NR_futex_time64 422
> +#define __NR_get_mempolicy 236
> +#define __NR_get_robust_list 100
> +#define __NR_getcpu 168
> +#define __NR_getcwd 17
> +#define __NR_getdents64 61
> +#define __NR_getegid 177
> +#define __NR_geteuid 175
> +#define __NR_getgid 176
> +#define __NR_getgroups 158
> +#define __NR_getitimer 102
> +#define __NR_getpeername 205
> +#define __NR_getpgid 155
> +#define __NR_getpid 172
> +#define __NR_getppid 173
> +#define __NR_getpriority 141
> +#define __NR_getrandom 278
> +#define __NR_getresgid 150
> +#define __NR_getresuid 148
> +#define __NR_getrlimit 163
> +#define __NR_getrusage 165
> +#define __NR_getsid 156
> +#define __NR_getsockname 204
> +#define __NR_getsockopt 209
> +#define __NR_gettid 178
> +#define __NR_gettimeofday 169
> +#define __NR_getuid 174
> +#define __NR_getxattr 8
> +#define __NR_init_module 105
> +#define __NR_inotify_add_watch 27
> +#define __NR_inotify_init1 26
> +#define __NR_inotify_rm_watch 28
> +#define __NR_io_cancel 3
> +#define __NR_io_destroy 1
> +#define __NR_io_getevents 4
> +#define __NR_io_pgetevents 292
> +#define __NR_io_pgetevents_time64 416
> +#define __NR_io_setup 0
> +#define __NR_io_submit 2
> +#define __NR_io_uring_enter 426
> +#define __NR_io_uring_register 427
> +#define __NR_io_uring_setup 425
> +#define __NR_ioctl 29
> +#define __NR_ioprio_get 31
> +#define __NR_ioprio_set 30
> +#define __NR_kcmp 272
> +#define __NR_kexec_file_load 294
> +#define __NR_kexec_load 104
> +#define __NR_keyctl 219
> +#define __NR_kill 129
> +#define __NR_landlock_add_rule 445
> +#define __NR_landlock_create_ruleset 444
> +#define __NR_landlock_restrict_self 446
> +#define __NR_lgetxattr 9
> +#define __NR_linkat 37
> +#define __NR_listen 201
> +#define __NR_listxattr 11
> +#define __NR_llistxattr 12
> +#define __NR_llseek 62
> +#define __NR_lookup_dcookie 18
> +#define __NR_lremovexattr 15
> +#define __NR_lsetxattr 6
> +#define __NR_madvise 233
> +#define __NR_mbind 235
> +#define __NR_membarrier 283
> +#define __NR_memfd_create 279
> +#define __NR_migrate_pages 238
> +#define __NR_mincore 232
> +#define __NR_mkdirat 34
> +#define __NR_mknodat 33
> +#define __NR_mlock 228
> +#define __NR_mlock2 284
> +#define __NR_mlockall 230
> +#define __NR_mmap2 222
> +#define __NR_mount 40
> +#define __NR_mount_setattr 442
> +#define __NR_move_mount 429
> +#define __NR_move_pages 239
> +#define __NR_mprotect 226
> +#define __NR_mq_getsetattr 185
> +#define __NR_mq_notify 184
> +#define __NR_mq_open 180
> +#define __NR_mq_timedreceive 183
> +#define __NR_mq_timedreceive_time64 419
> +#define __NR_mq_timedsend 182
> +#define __NR_mq_timedsend_time64 418
> +#define __NR_mq_unlink 181
> +#define __NR_mremap 216
> +#define __NR_msgctl 187
> +#define __NR_msgget 186
> +#define __NR_msgrcv 188
> +#define __NR_msgsnd 189
> +#define __NR_msync 227
> +#define __NR_munlock 229
> +#define __NR_munlockall 231
> +#define __NR_munmap 215
> +#define __NR_name_to_handle_at 264
> +#define __NR_nanosleep 101
> +#define __NR_nfsservctl 42
> +#define __NR_open_by_handle_at 265
> +#define __NR_open_tree 428
> +#define __NR_openat 56
> +#define __NR_openat2 437
> +#define __NR_or1k_atomic 244
> +#define __NR_perf_event_open 241
> +#define __NR_personality 92
> +#define __NR_pidfd_getfd 438
> +#define __NR_pidfd_open 434
> +#define __NR_pidfd_send_signal 424
> +#define __NR_pipe2 59
> +#define __NR_pivot_root 41
> +#define __NR_pkey_alloc 289
> +#define __NR_pkey_free 290
> +#define __NR_pkey_mprotect 288
> +#define __NR_ppoll 73
> +#define __NR_ppoll_time64 414
> +#define __NR_prctl 167
> +#define __NR_pread64 67
> +#define __NR_preadv 69
> +#define __NR_preadv2 286
> +#define __NR_prlimit64 261
> +#define __NR_process_madvise 440
> +#define __NR_process_mrelease 448
> +#define __NR_process_vm_readv 270
> +#define __NR_process_vm_writev 271
> +#define __NR_pselect6 72
> +#define __NR_pselect6_time64 413
> +#define __NR_ptrace 117
> +#define __NR_pwrite64 68
> +#define __NR_pwritev 70
> +#define __NR_pwritev2 287
> +#define __NR_quotactl 60
> +#define __NR_quotactl_fd 443
> +#define __NR_read 63
> +#define __NR_readahead 213
> +#define __NR_readlinkat 78
> +#define __NR_readv 65
> +#define __NR_reboot 142
> +#define __NR_recvfrom 207
> +#define __NR_recvmmsg 243
> +#define __NR_recvmmsg_time64 417
> +#define __NR_recvmsg 212
> +#define __NR_remap_file_pages 234
> +#define __NR_removexattr 14
> +#define __NR_renameat 38
> +#define __NR_renameat2 276
> +#define __NR_request_key 218
> +#define __NR_restart_syscall 128
> +#define __NR_rseq 293
> +#define __NR_rt_sigaction 134
> +#define __NR_rt_sigpending 136
> +#define __NR_rt_sigprocmask 135
> +#define __NR_rt_sigqueueinfo 138
> +#define __NR_rt_sigreturn 139
> +#define __NR_rt_sigsuspend 133
> +#define __NR_rt_sigtimedwait 137
> +#define __NR_rt_sigtimedwait_time64 421
> +#define __NR_rt_tgsigqueueinfo 240
> +#define __NR_sched_get_priority_max 125
> +#define __NR_sched_get_priority_min 126
> +#define __NR_sched_getaffinity 123
> +#define __NR_sched_getattr 275
> +#define __NR_sched_getparam 121
> +#define __NR_sched_getscheduler 120
> +#define __NR_sched_rr_get_interval 127
> +#define __NR_sched_rr_get_interval_time64 423
> +#define __NR_sched_setaffinity 122
> +#define __NR_sched_setattr 274
> +#define __NR_sched_setparam 118
> +#define __NR_sched_setscheduler 119
> +#define __NR_sched_yield 124
> +#define __NR_seccomp 277
> +#define __NR_semctl 191
> +#define __NR_semget 190
> +#define __NR_semop 193
> +#define __NR_semtimedop 192
> +#define __NR_semtimedop_time64 420
> +#define __NR_sendfile64 71
> +#define __NR_sendmmsg 269
> +#define __NR_sendmsg 211
> +#define __NR_sendto 206
> +#define __NR_set_mempolicy 237
> +#define __NR_set_robust_list 99
> +#define __NR_set_tid_address 96
> +#define __NR_setdomainname 162
> +#define __NR_setfsgid 152
> +#define __NR_setfsuid 151
> +#define __NR_setgid 144
> +#define __NR_setgroups 159
> +#define __NR_sethostname 161
> +#define __NR_setitimer 103
> +#define __NR_setns 268
> +#define __NR_setpgid 154
> +#define __NR_setpriority 140
> +#define __NR_setregid 143
> +#define __NR_setresgid 149
> +#define __NR_setresuid 147
> +#define __NR_setreuid 145
> +#define __NR_setrlimit 164
> +#define __NR_setsid 157
> +#define __NR_setsockopt 208
> +#define __NR_settimeofday 170
> +#define __NR_setuid 146
> +#define __NR_setxattr 5
> +#define __NR_shmat 196
> +#define __NR_shmctl 195
> +#define __NR_shmdt 197
> +#define __NR_shmget 194
> +#define __NR_shutdown 210
> +#define __NR_sigaltstack 132
> +#define __NR_signalfd4 74
> +#define __NR_socket 198
> +#define __NR_socketpair 199
> +#define __NR_splice 76
> +#define __NR_statfs64 43
> +#define __NR_statx 291
> +#define __NR_swapoff 225
> +#define __NR_swapon 224
> +#define __NR_symlinkat 36
> +#define __NR_sync 81
> +#define __NR_sync_file_range 84
> +#define __NR_syncfs 267
> +#define __NR_sysinfo 179
> +#define __NR_syslog 116
> +#define __NR_tee 77
> +#define __NR_tgkill 131
> +#define __NR_timer_create 107
> +#define __NR_timer_delete 111
> +#define __NR_timer_getoverrun 109
> +#define __NR_timer_gettime 108
> +#define __NR_timer_gettime64 408
> +#define __NR_timer_settime 110
> +#define __NR_timer_settime64 409
> +#define __NR_timerfd_create 85
> +#define __NR_timerfd_gettime 87
> +#define __NR_timerfd_gettime64 410
> +#define __NR_timerfd_settime 86
> +#define __NR_timerfd_settime64 411
> +#define __NR_times 153
> +#define __NR_tkill 130
> +#define __NR_truncate64 45
> +#define __NR_umask 166
> +#define __NR_umount2 39
> +#define __NR_uname 160
> +#define __NR_unlinkat 35
> +#define __NR_unshare 97
> +#define __NR_userfaultfd 282
> +#define __NR_utimensat 88
> +#define __NR_utimensat_time64 412
> +#define __NR_vhangup 58
> +#define __NR_vmsplice 75
> +#define __NR_wait4 260
> +#define __NR_waitid 95
> +#define __NR_write 64
> +#define __NR_writev 66
> diff --git a/sysdeps/unix/sysv/linux/or1k/bits/timesize.h b/sysdeps/unix/sysv/linux/or1k/bits/timesize.h
> new file mode 100644
> index 0000000000..3ab388da7f
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/bits/timesize.h
> @@ -0,0 +1,19 @@
> +/* Bit size of the time_t type at glibc build time, OpenRISC version.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#define __TIMESIZE	64

Ok, although I think we should flip the default to 64 bits make
old ports to override to 32.

> diff --git a/sysdeps/unix/sysv/linux/or1k/clone.c b/sysdeps/unix/sysv/linux/or1k/clone.c
> new file mode 100644
> index 0000000000..531fd17e29
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/clone.c
> @@ -0,0 +1,61 @@
> +/* OpenRISC helper for the clone syscall.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <stdarg.h>
> +#include <sysdep.h>
> +
> +extern int __or1k_clone (int (*fn)(void *), void *child_stack,
> +			 int flags, void *arg, pid_t *ptid,
> +			 void *tls, pid_t *ctid);
> +
> +
> +/* The OpenRISC ABI uses the stack for varargs like those using in clone
> +   but the linux syscall ABI uses registers.
> +   This function moves from varargs to regs.  */
> +int
> +__clone (int (*fn)(void *), void *child_stack,
> +	 int flags, void *arg, ...
> +	 /* pid_t *ptid, struct user_desc *tls, pid_t *ctid */ )
> +{
> +  void *ptid;
> +  void *tls;
> +  void *ctid;
> +  va_list ap;
> +  int err;
> +
> +  va_start (ap, arg);
> +  ptid = va_arg (ap, void *);
> +  tls = va_arg (ap, void *);
> +  ctid = va_arg (ap, void *);
> +  va_end (ap);
> +
> +  /* Sanity check the arguments */
> +  err = -EINVAL;
> +  if (!fn)
> +    goto syscall_error;
> +  if (!child_stack)
> +    goto syscall_error;
> +
> +  return __or1k_clone (fn, child_stack, flags, arg, ptid, tls, ctid);
> +
> +syscall_error:
> +  __set_errno (-err);
> +  return -1;
> +}
> +libc_hidden_def (__clone)
> +weak_alias (__clone, clone)

Ok, I take that implementing it solely on __or1k_clone is more complex than
using a C wrapper.

> diff --git a/sysdeps/unix/sysv/linux/or1k/jmp_buf-macros.h b/sysdeps/unix/sysv/linux/or1k/jmp_buf-macros.h
> new file mode 100644
> index 0000000000..3c5c1826ab
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/jmp_buf-macros.h
> @@ -0,0 +1,41 @@
> +/* jump buffer constants, OpenRISC version.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library.  If not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +/* Produced by this program:
> +
> +   #include <stdio.h>
> +   #include <unistd.h>
> +   #include <setjmp.h>
> +   #include <stddef.h>
> +
> +   int main (int argc, char **argv)
> +   {
> +       printf ("#define JMP_BUF_SIZE %d\n", sizeof (jmp_buf));
> +       printf ("#define JMP_BUF_ALIGN %d\n", __alignof__ (jmp_buf));
> +       printf ("#define SIGJMP_BUF_SIZE %d\n", sizeof (sigjmp_buf));
> +       printf ("#define SIGJMP_BUF_ALIGN %d\n", __alignof__ (sigjmp_buf));
> +       printf ("#define MASK_WAS_SAVED_OFFSET %d\n", offsetof (struct __jmp_buf_tag, __mask_was_saved));
> +       printf ("#define SAVED_MASK_OFFSET %d\n", offsetof (struct __jmp_buf_tag, __saved_mask));
> +   } */
> +
> +#define JMP_BUF_SIZE 184
> +#define JMP_BUF_ALIGN 4
> +#define SIGJMP_BUF_SIZE 184
> +#define SIGJMP_BUF_ALIGN 4
> +#define MASK_WAS_SAVED_OFFSET 52
> +#define SAVED_MASK_OFFSET 56

You don't need this file since bc801b3a40f3a9bc8f24f1d0fdc39413874c3172.

> diff --git a/sysdeps/unix/sysv/linux/or1k/mmap_internal.h b/sysdeps/unix/sysv/linux/or1k/mmap_internal.h
> new file mode 100644
> index 0000000000..817b841e5b
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/mmap_internal.h
> @@ -0,0 +1,28 @@
> +/* Common mmap definition for Linux implementation.  OpenRISC version.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef MMAP_OR1K_INTERNAL_LINUX_H
> +#define MMAP_OR1K_INTERNAL_LINUX_H
> +
> +/* OpenRISC Linux sets the page shift to 13 and mmap2 expects
> +   offsets to be provided in 8K pages.  */
> +#define MMAP2_PAGE_UNIT 8192ULL
> +
> +#include_next <mmap_internal.h>
> +
> +#endif

Ok.

> diff --git a/sysdeps/unix/sysv/linux/or1k/or1k_clone.S b/sysdeps/unix/sysv/linux/or1k/or1k_clone.S
> new file mode 100644
> index 0000000000..337eb17d06
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/or1k_clone.S
> @@ -0,0 +1,89 @@
> +/* clone helper __or1k_clone for OpenRISC.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, write to the Free
> +   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
> +   02111-1307 USA.  */
> +
> +#include <sysdep.h>
> +#include <tls.h>
> +#define __ASSEMBLY__
> +#include <linux/sched.h>
> +
> +	.text
> +ENTRY(__or1k_clone)
> +
> +	/* To handle GCC varargs we need to use our __clone wrapper to pop
> +	   everything from the stack for us.
> +	   Now everything is placed in the registers which saves us a lot
> +	   of trouble.
> +
> +	   The userland implementation is:
> +
> +	     int clone (int (*fn)(void *), void *child_stack,
> +			int flags, void *arg, pid_t *ptid,
> +			struct user_desc *tls, pid_t *ctid);
> +	   The kernel entry is:
> +
> +	     int clone (long flags, void *child_stack, int *parent_tid,
> +			int *child_tid, struct void *tls)
> +
> +	     NB: tls isn't really an argument, it is read from r7 directly.  */
> +
> +	/* First, align the stack to 4 bytes.  */
> +	l.xori	r11, r0, -4
> +	l.and	r4, r4, r11
> +
> +	/* Put 'fn', 'arg' and 'flags' on the child stack.  */
> +	l.addi	r4, r4, -12
> +	l.sw	8(r4), r3
> +	l.sw	4(r4), r6
> +	l.sw	0(r4), r5
> +
> +	l.ori	r3, r5, 0
> +	/* The child_stack is already in r4.  */
> +	l.ori	r5, r7, 0
> +	l.lwz	r6, 0(r1)
> +	l.ori	r7, r8, 0
> +
> +	DO_CALL (clone)
> +
> +	l.sfgeui r11, 0xf001
> +	l.bf	L(error)
> +	 l.nop
> +
> +	/* If we are not the child, return the pid.  */
> +	l.sfeqi	r11, 0
> +	l.bf	L(thread_start)
> +	 l.nop
> +
> +	l.jr	r9
> +	 l.nop
> +
> +L(thread_start):
> +	/* Load function from stack.  */
> +	l.lwz	r11, 8(r1)
> +	l.jalr	r11
> +	 l.lwz	r3, 4(r1)
> +
> +	/* Exit the child thread.  */
> +	l.ori	r3, r11, 0
> +	DO_CALL (exit)
> +
> +L(error):
> +	l.j	SYSCALL_ERROR_NAME
> +	 l.ori	r3, r11, 0
> +
> +PSEUDO_END (__or1k_clone)
> diff --git a/sysdeps/unix/sysv/linux/or1k/sysdep.c b/sysdeps/unix/sysv/linux/or1k/sysdep.c
> new file mode 100644
> index 0000000000..1130cba687
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/sysdep.c
> @@ -0,0 +1,34 @@
> +/* OpenRISC wrapper for setting errno.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library.  If not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#include <errno.h>
> +
> +long int __syscall_error (long int err);
> +hidden_proto (__syscall_error)
> +
> +/* This routine is jumped to by all the syscall handlers, to stash
> +   an error number into errno.  */
> +long int
> +__syscall_error (long int err)
> +{
> +  __set_errno (- err);
> +  return -1;
> +}
> +hidden_def (__syscall_error)
> diff --git a/sysdeps/unix/sysv/linux/or1k/sysdep.h b/sysdeps/unix/sysv/linux/or1k/sysdep.h
> new file mode 100644
> index 0000000000..5dd6da48a1
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/sysdep.h
> @@ -0,0 +1,201 @@
> +/* Assembler and syscall macros.  OpenRISC version.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library.  If not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef _LINUX_OR1K_SYSDEP_H
> +#define _LINUX_OR1K_SYSDEP_H 1
> +
> +#include <sysdeps/or1k/sysdep.h>
> +#include <sysdeps/unix/sysv/linux/generic/sysdep.h>
> +#include <tls.h>
> +
> +/* "workarounds" for generic code needing to handle 64-bit time_t.  */
> +
> +#undef __NR_clock_getres
> +#undef __NR_futex
> +#undef __NR_ppoll
> +#undef __NR_pselect6
> +#undef __NR_recvmmsg
> +#undef __NR_rt_sigtimedwait
> +#undef __NR_semtimedop
> +#undef __NR_utimensat
> +
> +/* Fix sysdeps/unix/sysv/linux/clock_getcpuclockid.c.  */
> +#define __NR_clock_getres	__NR_clock_getres_time64
> +/* Fix sysdeps/nptl/lowlevellock-futex.h.  */
> +#define __NR_futex		__NR_futex_time64
> +/* Fix sysdeps/unix/sysv/linux/pause.c.  */
> +#define __NR_ppoll		__NR_ppoll_time64
> +/* Fix sysdeps/unix/sysv/linux/select.c.  */
> +#define __NR_pselect6		__NR_pselect6_time64
> +/* Fix sysdeps/unix/sysv/linux/recvmmsg.c.  */
> +#define __NR_recvmmsg		__NR_recvmmsg_time64
> +/* Fix sysdeps/unix/sysv/linux/sigtimedwait.c.  */
> +#define __NR_rt_sigtimedwait	__NR_rt_sigtimedwait_time64
> +/* Fix sysdeps/unix/sysv/linux/semtimedop.c.  */
> +#define __NR_semtimedop		__NR_semtimedop_time64
> +/* Hack sysdeps/unix/sysv/linux/generic/utimes.c.  */
> +#define __NR_utimensat		__NR_utimensat_time64
> +
> +#undef SYS_ify
> +#define SYS_ify(syscall_name)   (__NR_##syscall_name)
> +
> +/* Linux uses a negative return value to indicate syscall errors,
> +   unlike most Unices, which use the condition codes' carry flag.
> +
> +   Since version 2.1 the return value of a system call might be
> +   negative even if the call succeeded.  E.g., the lseek system call
> +   might return a large offset.  Therefore we must not anymore test
> +   for < 0, but test for a real error by making sure the value in R0
> +   is a real error number.  Linus said he will make sure the no syscall
> +   returns a value in -1 .. -4095 as a valid result so we can safely
> +   test with -4095.  */
> +
> +#ifdef __ASSEMBLER__
> +
> +/* Macros used in syscall-template.S */
> +#define ret          l.jr r9; l.nop
> +#define ret_NOERRNO  l.jr r9; l.nop
> +
> +#undef	DO_CALL
> +#define DO_CALL(syscall_name) \
> +  l.addi r11, r0, SYS_ify (syscall_name); \
> +  l.sys 1; \
> +   l.nop
> +
> +#undef	PSEUDO
> +#define PSEUDO(name, syscall_name, args) \
> +  ENTRY (name); \
> +  DO_CALL(syscall_name); \
> +  /* if -4096 < ret < 0 holds, it's an error */ \
> +  l.sfgeui r11, 0xf001; \
> +  l.bf L(pseudo_end); \
> +   l.nop
> +
> +#undef	PSEUDO_NOERRNO
> +#define PSEUDO_NOERRNO(name, syscall_name, args)  \
> +  ENTRY (name);           \
> +  DO_CALL(syscall_name)
> +
> +#undef	PSEUDO_END
> +#define PSEUDO_END(name) \
> +L(pseudo_end): \
> +  l.j SYSCALL_ERROR_NAME; \
> +  l.ori r3,r11,0; \
> +  END (name)
> +
> +#undef	PSEUDO_END_NOERRNO
> +#define PSEUDO_END_NOERRNO(name) \
> +  END (name)
> +
> +#ifndef PIC
> +/* For static code, on error jump to __syscall_error directly.  */
> +# define SYSCALL_ERROR_NAME __syscall_error
> +#elif !IS_IN (libc)
> +/* Use the internal name for libc shared objects.  */
> +# define SYSCALL_ERROR_NAME __GI___syscall_error
> +#else
> +/* Otherwise, on error do a full PLT jump.  */
> +# define SYSCALL_ERROR_NAME plt(__syscall_error)
> +#endif
> +
> +#else /* not __ASSEMBLER__ */
> +
> +#include <errno.h>
> +
> +extern long int __syscall_error (long int neg_errno);
> +
> +/* Pointer mangling is not yet supported for or1k.  */
> +#define PTR_MANGLE(var) (void) (var)
> +#define PTR_DEMANGLE(var) (void) (var)
> +
> +#undef INTERNAL_SYSCALL
> +#define INTERNAL_SYSCALL(name, nr, args...) \
> +	INTERNAL_SYSCALL_NCS (SYS_ify (name), nr, args)
> +
> +/* The _NCS variant allows non-constant syscall numbers.  */
> +#undef INTERNAL_SYSCALL_NCS
> +#define INTERNAL_SYSCALL_NCS(number, nr, args...) \
> +        ({ unsigned long int __sys_result;                                     \
> +          {                                                                    \
> +            long int _sc_ret = (long int) number;                              \
> +            LOAD_ARGS_##nr (args)                                              \
> +            register long int __sc_ret __asm__ ("r11") = _sc_ret;              \
> +            __asm__ __volatile__ ("l.sys 1\n\t"                                \
> +				  " l.nop\n\t"                                 \
> +                                  : "+r" (__sc_ret)                            \
> +                                  : ASM_ARGS_##nr                              \
> +                                  : ASM_CLOBBERS_##nr                          \
> +                                    "r12", "r13", "r15", "r17", "r19",         \
> +                                    "r21", "r23", "r25", "r27", "r29",         \
> +                                    "r31", "memory");                          \
> +            __sys_result = __sc_ret;                                           \
> +          }                                                                    \
> +          (long int) __sys_result; })
> +
> +/* From here on we have nested macros that generate code for
> +   setting up syscall arguments.  */
> +
> +#define LOAD_ARGS_0()
> +
> +#define ASM_ARGS_0
> +#define ASM_CLOBBERS_0  "r3", ASM_CLOBBERS_1
> +
> +#define LOAD_ARGS_1(a) \
> +  long int _a = (long int)(a);                             \
> +  register long int __a __asm__ ("r3") = _a;
> +#define ASM_ARGS_1 "r" (__a)
> +#define ASM_CLOBBERS_1  "r4", ASM_CLOBBERS_2
> +
> +#define LOAD_ARGS_2(a, b) \
> +  long int _b = (long int)(b);                             \
> +  LOAD_ARGS_1 (a)                                          \
> +  register long int __b __asm__ ("r4") = _b;
> +#define ASM_ARGS_2 ASM_ARGS_1, "r" (__b)
> +#define ASM_CLOBBERS_2  "r5", ASM_CLOBBERS_3
> +
> +#define LOAD_ARGS_3(a, b, c) \
> +  long int _c = (long int)(c);                             \
> +  LOAD_ARGS_2 (a, b)                                       \
> +  register long int __c __asm__ ("r5") = _c;
> +#define ASM_ARGS_3 ASM_ARGS_2, "r" (__c)
> +#define ASM_CLOBBERS_3  "r6", ASM_CLOBBERS_4
> +
> +#define LOAD_ARGS_4(a, b, c, d) \
> +    LOAD_ARGS_3 (a, b, c)                                  \
> +  long int _d = (long int)(d);                             \
> +  register long int __d __asm__ ("r6") = _d;
> +#define ASM_ARGS_4 ASM_ARGS_3, "r" (__d)
> +#define ASM_CLOBBERS_4  "r7", ASM_CLOBBERS_5
> +
> +#define LOAD_ARGS_5(a, b, c, d, e) \
> +  long int _e = (long int)(e);                             \
> +  LOAD_ARGS_4 (a, b, c, d)                                 \
> +  register long int __e __asm__ ("r7") = _e;
> +#define ASM_ARGS_5 ASM_ARGS_4, "r" (__e)
> +#define ASM_CLOBBERS_5  "r8", ASM_CLOBBERS_6
> +
> +#define LOAD_ARGS_6(a, b, c, d, e, f) \
> +  long int _f = (long int)(f);                             \
> +  LOAD_ARGS_5 (a, b, c, d, e)                              \
> +  register long int __f __asm__ ("r8") = _f;
> +#define ASM_ARGS_6 ASM_ARGS_5, "r" (__f)
> +#define ASM_CLOBBERS_6
> +
> +#endif /* not __ASSEMBLER__ */
> +
> +#endif /* linux/or1k/sysdep.h */