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.Dd August 16, 2018
.Dt VFS_SET 9
.Os
.Sh NAME
.Nm VFS_SET
.Nd set up loadable file system
.Vt vfsconf
.Sh SYNOPSIS
.In sys/param.h
.In sys/kernel.h
.In sys/module.h
.In sys/mount.h
.Ft void
.Fn VFS_SET "struct vfsops *vfsops" "fsname" "int flags"
.Sh DESCRIPTION
.Fn VFS_SET
creates a
.Vt vfsconf
structure for the loadable module with the given
.Fa vfsops , fsname
and
.Fa flags ,
and declares it by calling
.Xr DECLARE_MODULE 9
using
.Fn vfs_modevent
as the event handler.
.Pp
Possible values for the
.Fa flags
argument are:
.Bl -hang -width ".Dv VFCF_DELEGADMIN"
.It Dv VFCF_STATIC
File system should be statically available in the kernel.
.It Dv VFCF_NETWORK
Network exportable file system.
.It Dv VFCF_READONLY
Does not support write operations.
.It Dv VFCF_SYNTHETIC
Pseudo file system, data does not represent on-disk files.
.It Dv VFCF_LOOPBACK
Loopback file system layer.
.It Dv VFCF_UNICODE
File names are stored as Unicode.
.It Dv VFCF_JAIL
Can be mounted from within a jail if
.Va allow.mount
and
.Va allow.mount.<fsname>
jail parameters are set.
.It Dv VFCF_DELEGADMIN
Supports delegated administration if
.Va vfs.usermount
sysctl is set to
.Dv 1 .
.It Dv VFCF_SBDRY
When in VFS method, the thread suspension is deferred to the user
boundary upon arrival of stop action.
.El
.Sh PSEUDOCODE
.Bd -literal
/*
 * Fill in the fields for which we have special methods.
 * The others are initially null.  This tells vfs to change them to
 * pointers to vfs_std* functions during file system registration.
 */
static struct vfsops myfs_vfsops = {
        .vfs_mount =    myfs_mount,
        .vfs_root =     myfs_root,
        .vfs_statfs =   myfs_statfs,
        .vfs_unmount =  myfs_unmount,
};

VFS_SET(myfs_vfsops, myfs, 0);
.Ed
.Sh SEE ALSO
.Xr jail 2 ,
.Xr jail 8 ,
.Xr DECLARE_MODULE 9 ,
.Xr vfs_modevent 9 ,
.Xr vfsconf 9
.Sh AUTHORS
This manual page was written by
.An Chad David Aq Mt davidc@acns.ab.ca .