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Diffstat (limited to 'static/freebsd/man9/syscall_helper_register.9')
| -rw-r--r-- | static/freebsd/man9/syscall_helper_register.9 | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/static/freebsd/man9/syscall_helper_register.9 b/static/freebsd/man9/syscall_helper_register.9 new file mode 100644 index 00000000..bad8eee3 --- /dev/null +++ b/static/freebsd/man9/syscall_helper_register.9 @@ -0,0 +1,137 @@ +.\" Copyright (c) 2018 Conrad Meyer <cem@FreeBSD.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd February 10, 2018 +.Dt SYSCALL_HELPER_REGISTER 9 +.Os +.Sh NAME +.Nm syscall_helper_register , +.Nm syscall_helper_unregister +.Nd kernel syscall registration routines +.\" +.Sh SYNOPSIS +.In sys/sysent.h +.Ft int +.Fn syscall_helper_register "struct syscall_helper_data *sd" "int flags" +.Ft int +.Fn syscall_helper_unregister "struct syscall_helper_data *sd" +.\" +.Ss INITIALIZER MACROS +.Ft struct syscall_helper_data +.Fn SYSCALL_INIT_HELPER "syscallname" +.Ft struct syscall_helper_data +.Fn SYSCALL_INIT_HELPER_F "syscallname" "int flags" +.\" +.Ss COMPATIBILITY INITIALIZER MACROS +.Ft struct syscall_helper_data +.Fn SYSCALL_INIT_HELPER_COMPAT "syscallname" +.Ft struct syscall_helper_data +.Fn SYSCALL_INIT_HELPER_COMPAT_F "syscallname" "int flags" +.\" +.Sh DESCRIPTION +The +.Fn syscall_helper_register +registers a system call. +This function takes the structure +.Va struct syscall_helper_data sd , +which specifies the parameters for syscall registration: +.Pp +.Bd -literal -offset indent -compact +struct syscall_helper_data { + struct sysent new_sysent; + struct sysent old_sysent; + int syscall_no; + int registered; +}; +.Ed +.Pp +The only valid flag for the +.Fa flags +argument to +.Fn syscall_helper_register +is +.Dv SY_THR_STATIC . +This flag prevents the syscall from being unregistered. +.\" +.Pp +Before use, the structure must be initialized with one of the +.Fn SYSCALL_INIT_HELPER* +macros. +In new code, syscall implementation functions shall be named +.Fn sys_syscallname +and the regular macros shall be used. +.Pp +For legacy syscall functions named without "sys_" prefixes, the "COMPAT" +versions of the macros may be used. +.Pp +The only valid flag for the +.Fa flags +argument to the "F" variants of the initializer macros is +.Dv SYF_CAPENABLED . +This flag indicates that the syscall is allowed in capability mode. +.Pp +The +.Fn syscall_helper_unregister +unregisters a system call. +This function takes the same structure +.Va struct syscall_helper_data sd +that was previously initialized in the manner described above and used in a +successful invocation of +.Fn syscall_helper_register . +.\" +.Sh RETURN VALUES +If successful, +.Fn syscall_helper_register +and +.Fn syscall_helper_unregister +will return 0. +Otherwise, they will return an error. +.\" +.Sh ERRORS +The +.Fn syscall_helper_register +call will fail and the syscall will not be registered if: +.Bl -tag -width Er +.It Bq Er EINVAL +The +.Fa flags +argument contained a value other than +.Dv SY_THR_STATIC . +.It Bq Er EINVAL +The specified syscall number, +.Dv sd.syscall_no +.Dv ( SYS_syscallname ) , +was outside of the valid range of system call numbers (zero through +.Dv SYS_MAXSYSCALL ) . +.It Bq Er ENFILE +The system call table does not have any available slots. +.It Bq Er EEXIST +The specified syscall number, +.Dv sd.syscall_no +.Dv ( SYS_syscallname ) , +was already in use. +.El +.\" +.Sh SEE ALSO +.Xr SYSCALL_MODULE 9 |