Re: [PATCH v7 07/13] LoongArch: Linux Syscall Interface

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

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

On 18/07/22 22:20, caiyinyu wrote:
> ---
>  sysdeps/loongarch/abort-instr.h               |   2 +
>  sysdeps/loongarch/hp-timing.h                 |  42 +++
>  .../unix/sysv/linux/loongarch/arch-syscall.h  | 301 ++++++++++++++++
>  sysdeps/unix/sysv/linux/loongarch/clone.S     |  96 ++++++
>  sysdeps/unix/sysv/linux/loongarch/clone3.S    |  83 +++++
>  sysdeps/unix/sysv/linux/loongarch/sysdep.S    |  53 +++
>  sysdeps/unix/sysv/linux/loongarch/sysdep.h    | 320 ++++++++++++++++++
>  sysdeps/unix/sysv/linux/loongarch/vfork.S     |  50 +++
>  8 files changed, 947 insertions(+)
>  create mode 100644 sysdeps/loongarch/abort-instr.h
>  create mode 100644 sysdeps/loongarch/hp-timing.h
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/arch-syscall.h
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/clone.S
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/clone3.S
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/sysdep.S
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/sysdep.h
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/vfork.S
> 
> diff --git a/sysdeps/loongarch/abort-instr.h b/sysdeps/loongarch/abort-instr.h
> new file mode 100644
> index 0000000000..46d3ad0871
> --- /dev/null
> +++ b/sysdeps/loongarch/abort-instr.h
> @@ -0,0 +1,2 @@
> +/* An instruction which should crash any program is a breakpoint.  */
> +#define ABORT_INSTRUCTION asm ("break 0")
> diff --git a/sysdeps/loongarch/hp-timing.h b/sysdeps/loongarch/hp-timing.h
> new file mode 100644
> index 0000000000..af1da81024
> --- /dev/null
> +++ b/sysdeps/loongarch/hp-timing.h
> @@ -0,0 +1,42 @@
> +/* High precision, low overhead timing functions.
> +   Copyright (C) 2022 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 _HP_TIMING_H
> +#define _HP_TIMING_H 1
> +
> +/* We always assume having the timestamp register.  */
> +#define HP_TIMING_AVAIL (1)
> +#define HP_SMALL_TIMING_AVAIL (1)
> +
> +/* We indeed have inlined functions.  */
> +#define HP_TIMING_INLINE (1)
> +
> +/* We use 64bit values for the times.  */
> +typedef unsigned long long int hp_timing_t;
> +
> +/* Read the stable counter.  */
> +#define HP_TIMING_NOW(Var) \
> +  ({ \
> +    unsigned long long int _count; \
> +    asm volatile ("rdtime.d\t%0,$r0" : "=r" (_count)); \
> +    (Var) = _count; \
> +  })
> +
> +#include <hp-timing-common.h>
> +
> +#endif /* hp-timing.h */
> diff --git a/sysdeps/unix/sysv/linux/loongarch/arch-syscall.h b/sysdeps/unix/sysv/linux/loongarch/arch-syscall.h
> new file mode 100644
> index 0000000000..6bb3c8adbc
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/arch-syscall.h
> @@ -0,0 +1,301 @@
> +/* 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_getres 114
> +#define __NR_clock_gettime 113
> +#define __NR_clock_nanosleep 115
> +#define __NR_clock_settime 112
> +#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 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_fcntl 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_fstatfs 44
> +#define __NR_fsync 82
> +#define __NR_ftruncate 46
> +#define __NR_futex 98
> +#define __NR_futex_waitv 449
> +#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_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_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_lookup_dcookie 18
> +#define __NR_lremovexattr 15
> +#define __NR_lseek 62
> +#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_mmap 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_timedsend 182
> +#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_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_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_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_recvmsg 212
> +#define __NR_remap_file_pages 234
> +#define __NR_removexattr 14
> +#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_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_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_sendfile 71
> +#define __NR_sendmmsg 269
> +#define __NR_sendmsg 211
> +#define __NR_sendto 206
> +#define __NR_set_mempolicy 237
> +#define __NR_set_mempolicy_home_node 450
> +#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_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_statfs 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_settime 110
> +#define __NR_timerfd_create 85
> +#define __NR_timerfd_gettime 87
> +#define __NR_timerfd_settime 86
> +#define __NR_times 153
> +#define __NR_tkill 130
> +#define __NR_truncate 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_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/loongarch/clone.S b/sysdeps/unix/sysv/linux/loongarch/clone.S
> new file mode 100644
> index 0000000000..c73245be82
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/clone.S
> @@ -0,0 +1,96 @@
> +/* The clone syscall wrapper.
> +   Copyright (C) 2022 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/>.  */
> +
> +/* clone() is even more special than fork() as it mucks with stacks
> +   and invokes a function in the right context after its all over.  */
> +
> +#include <sys/asm.h>
> +#include <sysdep.h>
> +#define _ERRNO_H  1
> +#include <bits/errno.h>
> +#include <tls.h>
> +#include "tcb-offsets.h"
> +
> +/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
> +   void *parent_tidptr, void *tls, void *child_tidptr) */
> +
> +ENTRY (__clone)
> +
> +	/* Align stack to 16.  */
> +	BSTRINS		a1, zero, 3, 0
> +
> +	/* Sanity check arguments.  */
> +	beqz		a0, L (invalid) /* No NULL function pointers.  */
> +	beqz		a1, L (invalid) /* No NULL stack pointers.  */
> +
> +	ADDI 		a1, a1, -16 /* Reserve argument save space.  */
> +	REG_S		a0, a1, 0   /* Save function pointer.  */
> +	REG_S		a3, a1, SZREG   /* Save argument pointer.  */
> +
> +	/* The syscall expects the args to be in different slots.  */
> +	or		a0, a2, zero
> +	or		a2, a4, zero
> +	or		a3, a6, zero
> +	or		a4, a5, zero
> +
> +	/* Do the system call.  */
> +	LI		a7,__NR_clone
> +	syscall		0
> +
> +	blt		a0, zero ,L (error)
> +	beqz		a0,L (thread_start)
> +
> +	/* Successful return from the parent.  */
> +	ret
> +
> +L (invalid):
> +	LI		a0, -EINVAL
> +
> +	/* Something bad happened -- no child created.  */
> +L (error):
> +	b		__syscall_error
> +
> +END (__clone)
> +
> +/* Load up the arguments to the function.  Put this block of code in
> +   its own function so that we can terminate the stack trace with our
> +   debug info.  */
> +ENTRY (__thread_start)
> +L (thread_start):
> +
> +/* Terminate call stack by noting ra is undefined.  Use a dummy
> +   .cfi_label to force starting the FDE.  */
> +	.cfi_label .Ldummy
> +	cfi_undefined (1)
> +
> +	/* Restore the arg for user's function.  */
> +	REG_L		a1, sp, 0   /* Function pointer.  */
> +	REG_L		a0, sp, SZREG   /* Argument pointer.  */
> +
> +	/* Call the user's function.  */
> +	jirl		ra, a1, 0
> +
> +	/* Call exit with the function's return value.  */
> +	LI		a7, __NR_exit
> +	syscall		0
> +
> +	END (__thread_start)
> +
> +libc_hidden_def (__clone)
> +weak_alias (__clone, clone)
> diff --git a/sysdeps/unix/sysv/linux/loongarch/clone3.S b/sysdeps/unix/sysv/linux/loongarch/clone3.S
> new file mode 100644
> index 0000000000..38be4c809b
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/clone3.S
> @@ -0,0 +1,83 @@
> +/* The clone3 syscall wrapper.
> +   Copyright (C) 2022 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/>.  */
> +
> +/* clone3() is even more special than fork() as it mucks with stacks
> +   and invokes a function in the right context after its all over.  */
> +
> +#include <sys/asm.h>
> +#include <sysdep.h>
> +#define _ERRNO_H  1
> +#include <bits/errno.h>
> +#include <tls.h>
> +#include "tcb-offsets.h"
> +
> +/* int clone3(struct clone_args *cl_args, size_t size,
> +   int (*func)(void *arg), void *arg); */
> +
> +ENTRY (__clone3)
> +
> +	/* Sanity check arguments.  */
> +	beqz		a0, L (invalid)	/* No NULL cl_args pointer.  */
> +	beqz		a2, L (invalid)	/* No NULL function pointer.  */
> +
> +	/* Do the system call.  */
> +	LI		a7, __NR_clone3
> +	syscall		0
> +
> +	blt		a0, zero ,L (error)
> +	beqz		a0, L (thread_start3)
> +
> +	/* Successful return from the parent.  */
> +	ret
> +
> +L (invalid):
> +	LI		a0, -EINVAL
> +
> +	/* Something bad happened -- no child created.  */
> +L (error):
> +	b		__syscall_error
> +
> +END (__clone3)
> +
> +/* Load up the arguments to the function.  Put this block of code in
> +   its own function so that we can terminate the stack trace with our
> +   debug info.  */
> +ENTRY (__thread_start3)
> +L (thread_start3):
> +
> +/* Terminate call stack by noting ra is undefined.  Use a dummy
> +   .cfi_label to force starting the FDE.  */
> +	.cfi_label .Ldummy
> +	cfi_undefined (1)
> +
> +	/* Align stack to 16.  */
> +	BSTRINS		sp, zero, 3, 0
> +
> +	/* Set up arguments for the function call.  */
> +	move		a0, a3		/* Argument.  */
> +	jirl		ra, a2, 0	/* Call function.  */
> +
> +	/* Call exit with the function's return value.  */
> +	LI		a7, __NR_exit
> +	syscall		0
> +
> +	END (__thread_start3)
> +
> +libc_hidden_def (__clone3)
> +weak_alias (__clone3, clone3)
> diff --git a/sysdeps/unix/sysv/linux/loongarch/sysdep.S b/sysdeps/unix/sysv/linux/loongarch/sysdep.S
> new file mode 100644
> index 0000000000..a4db2a97b5
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/sysdep.S
> @@ -0,0 +1,53 @@
> +/* syscall error handlers
> +   Copyright (C) 2022 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>
> +
> +#if IS_IN (libc)
> +# define errno __libc_errno
> +#endif
> +
> +ENTRY (__syscall_error)
> +/* Fall through to __syscall_set_errno */
> +END (__syscall_error)
> +
> +/* Non-standard calling convention: argument in a0, return address in t0,
> +   and clobber only t1.
> + */
> +ENTRY (__syscall_set_errno)
> +
> +/* We got here because a0 < 0, but only codes in the range [-4095, -1]
> +   represent errors.  Otherwise, just return the result normally.
> + */
> +	li.d		t1, -4096
> +	bgeu		t1, a0, L (out)
> +	sub.w		a0, zero, a0
> +#if RTLD_PRIVATE_ERRNO
> +	la		t1, rtld_errno
> +#elif defined(__PIC__)
> +	la.tls.ie	t1, errno
> +	add.d		t1, tp, t1
> +#else
> +	la.tls.le	t1, errno
> +	add.d		t1, tp, t1
> +#endif
> +	st.w		a0, t1, 0
> +	li.d		a0, -1
> +L (out):
> +	ret
> +END (__syscall_set_errno)
> diff --git a/sysdeps/unix/sysv/linux/loongarch/sysdep.h b/sysdeps/unix/sysv/linux/loongarch/sysdep.h
> new file mode 100644
> index 0000000000..c586df819c
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/sysdep.h
> @@ -0,0 +1,320 @@
> +/* Assembly macros for LoongArch.
> +   Copyright (C) 2022 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_LOONGARCH_SYSDEP_H
> +#define _LINUX_LOONGARCH_SYSDEP_H 1
> +
> +#include <sysdeps/unix/sysv/linux/generic/sysdep.h>
> +#include <tls.h>
> +
> +#ifdef __ASSEMBLER__
> +
> +#include <sys/asm.h>
> +#define ret jirl zero, ra, 0
> +#define L(label) .L##label
> +
> +/* Performs a system call, handling errors by setting errno.  Linux indicates
> +   errors by setting a0 to a value between -1 and -4095.  */
> +#undef PSEUDO
> +#define PSEUDO(name, syscall_name, args) \
> +  ENTRY (name); \
> +  li.d a7, SYS_ify (syscall_name); \
> +  syscall 0; \
> +  li.d a7, -4096; \
> +  bltu a7, a0, .Lsyscall_error##name;
> +
> +#undef PSEUDO_END
> +#define PSEUDO_END(sym) \
> +  SYSCALL_ERROR_HANDLER (sym); \
> +  ret; \
> +  END (sym);
> +
> +#if !IS_IN(libc)
> +#if RTLD_PRIVATE_ERRNO
> +
> +#define SYSCALL_ERROR_HANDLER(name) \
> +  .Lsyscall_error##name : la t0, rtld_errno; \
> +  sub.w a0, zero, a0; \
> +  st.w a0, t0, 0; \
> +  li.d a0, -1;
> +
> +#else
> +
> +#define SYSCALL_ERROR_HANDLER(name) \
> +  .Lsyscall_error##name : la.tls.ie t0, errno; \
> +  add.d t0, tp, t0; \
> +  sub.w a0, zero, a0; \
> +  st.w a0, t0, 0; \
> +  li.d a0, -1;
> +
> +#endif
> +#else
> +
> +#define SYSCALL_ERROR_HANDLER(name) .Lsyscall_error##name : b __syscall_error;
> +
> +#endif
> +
> +/* Performs a system call, not setting errno.  */
> +#undef PSEUDO_NEORRNO
> +#define PSEUDO_NOERRNO(name, syscall_name, args) \
> +  ENTRY (name); \
> +  li.d a7, SYS_ify (syscall_name); \
> +  syscall 0;
> +
> +#undef PSEUDO_END_NOERRNO
> +#define PSEUDO_END_NOERRNO(name) END (name);
> +
> +#undef ret_NOERRNO
> +#define ret_NOERRNO ret
> +
> +/* Perfroms a system call, returning the error code.  */
> +#undef PSEUDO_ERRVAL
> +#define PSEUDO_ERRVAL(name, syscall_name, args) \
> +  PSEUDO_NOERRNO (name, syscall_name, args); \
> +  slli.d a0, a0, 32; \
> +  srai.d a0, a0, 32; /* sign_ext */ \
> +  sub.d a0, zero, a0;
> +
> +#undef PSEUDO_END_ERRVAL
> +#define PSEUDO_END_ERRVAL(name) END (name);
> +
> +#undef ret_ERRVAL
> +#define ret_ERRVAL ret
> +
> +#endif /* __ASSEMBLER__ */
> +
> +/* In order to get __set_errno() definition in INLINE_SYSCALL.  */
> +#ifndef __ASSEMBLER__
> +#include <errno.h>
> +#endif
> +
> +#include <sysdeps/unix/sysdep.h>
> +
> +#undef SYS_ify
> +#define SYS_ify(syscall_name) __NR_##syscall_name
> +
> +#ifndef __ASSEMBLER__
> +
> +#define VDSO_NAME "LINUX_2.6"
> +#define VDSO_HASH 61765110
> +
> +/* List of system calls which are supported as vsyscalls.  */
> +#define HAVE_CLOCK_GETRES64_VSYSCALL "__vdso_clock_getres"
> +#define HAVE_CLOCK_GETTIME64_VSYSCALL "__vdso_clock_gettime"
> +#define HAVE_GETCPU_VSYSCALL "__vdso_getcpu"
> +
> +#define HAVE_CLONE3_WRAPPER 1
> +
> +#define INTERNAL_SYSCALL(name, nr, args...) \
> +  internal_syscall##nr (SYS_ify (name), args)
> +
> +#define INTERNAL_SYSCALL_NCS(number, nr, args...) \
> +  internal_syscall##nr (number, args)
> +
> +#define internal_syscall0(number, dummy...) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0"); \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "=r"(__a0) \
> +		       : "r"(__a7) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall1(number, arg0) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall2(number, arg0, arg1) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall3(number, arg0, arg1, arg2) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      long int _arg2 = (long int) (arg2); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      register long int __a2 asm ("$a2") = _arg2; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1), "r"(__a2) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall4(number, arg0, arg1, arg2, arg3) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      long int _arg2 = (long int) (arg2); \
> +      long int _arg3 = (long int) (arg3); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      register long int __a2 asm ("$a2") = _arg2; \
> +      register long int __a3 asm ("$a3") = _arg3; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1), "r"(__a2), "r"(__a3) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall5(number, arg0, arg1, arg2, arg3, arg4) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      long int _arg2 = (long int) (arg2); \
> +      long int _arg3 = (long int) (arg3); \
> +      long int _arg4 = (long int) (arg4); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      register long int __a2 asm ("$a2") = _arg2; \
> +      register long int __a3 asm ("$a3") = _arg3; \
> +      register long int __a4 asm ("$a4") = _arg4; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1), "r"(__a2), \
> +			 "r"(__a3), "r"(__a4) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall6(number, arg0, arg1, arg2, arg3, arg4, arg5) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      long int _arg2 = (long int) (arg2); \
> +      long int _arg3 = (long int) (arg3); \
> +      long int _arg4 = (long int) (arg4); \
> +      long int _arg5 = (long int) (arg5); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      register long int __a2 asm ("$a2") = _arg2; \
> +      register long int __a3 asm ("$a3") = _arg3; \
> +      register long int __a4 asm ("$a4") = _arg4; \
> +      register long int __a5 asm ("$a5") = _arg5; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1), "r"(__a2), "r"(__a3), \
> +			 "r"(__a4), "r"(__a5) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define internal_syscall7(number, arg0, arg1, arg2, arg3, arg4, arg5, arg6) \
> +  ({ \
> +    long int _sys_result; \
> +\
> +    { \
> +      long int _arg0 = (long int) (arg0); \
> +      long int _arg1 = (long int) (arg1); \
> +      long int _arg2 = (long int) (arg2); \
> +      long int _arg3 = (long int) (arg3); \
> +      long int _arg4 = (long int) (arg4); \
> +      long int _arg5 = (long int) (arg5); \
> +      long int _arg6 = (long int) (arg6); \
> +      register long int __a7 asm ("$a7") = number; \
> +      register long int __a0 asm ("$a0") = _arg0; \
> +      register long int __a1 asm ("$a1") = _arg1; \
> +      register long int __a2 asm ("$a2") = _arg2; \
> +      register long int __a3 asm ("$a3") = _arg3; \
> +      register long int __a4 asm ("$a4") = _arg4; \
> +      register long int __a5 asm ("$a5") = _arg5; \
> +      register long int __a6 asm ("$a6") = _arg6; \
> +      __asm__ volatile ("syscall 0\n\t" \
> +		       : "+r"(__a0) \
> +		       : "r"(__a7), "r"(__a1), "r"(__a2), "r"(__a3), \
> +			 "r"(__a4), "r"(__a5), "r"(__a6) \
> +		       : __SYSCALL_CLOBBERS); \
> +      _sys_result = __a0; \
> +    } \
> +    _sys_result; \
> +  })
> +
> +#define __SYSCALL_CLOBBERS \
> +  "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8", "memory"
> +
> +extern long int __syscall_error (long int neg_errno);
> +
> +#endif /* ! __ASSEMBLER__ */
> +
> +/* Pointer mangling is not supported.  */
> +#define PTR_MANGLE(var) (void) (var)
> +#define PTR_DEMANGLE(var) (void) (var)
> +
> +#endif /* linux/loongarch/sysdep.h */
> diff --git a/sysdeps/unix/sysv/linux/loongarch/vfork.S b/sysdeps/unix/sysv/linux/loongarch/vfork.S
> new file mode 100644
> index 0000000000..fcc84e3549
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/vfork.S
> @@ -0,0 +1,50 @@
> +/* vfork for Linux.
> +   Copyright (C) 2022 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>
> +#define _ERRNO_H  1
> +#include <bits/errno.h>
> +
> +/* Clone the calling process, but without copying the whole address space.
> +   The calling process is suspended until the new process exits or is
> +   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
> +   and the process ID of the new process to the old process.  */
> +
> +ENTRY (__vfork)
> +
> +	li.d	a0, 0x4111 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
> +	add.d   a1, zero, sp
> +
> +	/* Do the system call.  */
> +	li.d	a7, __NR_clone
> +	syscall	0
> +
> +	blt	a0, zero ,L (error)
> +
> +	ret
> +
> +L (error):
> +	b	__syscall_error
> +
> +END (__vfork)
> +
> +libc_hidden_def (__vfork)
> +
> +weak_alias (__vfork, vfork)
> +strong_alias (__vfork, __libc_vfork)