xref: /dflybsd-src/share/man/man5/dirfs.5 (revision 1012d7827f4145ff76f5077a2d9a915880da2748)
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28.Dd September 5, 2013
29.Dt DIRFS 5
30.Os
31.Sh NAME
32.Nm dirfs
33.Nd "pseudo-filesystem for vkernel"
34.Sh SYNOPSIS
35To compile this driver into the vkernel,
36place the following line in your
37vkernel configuration file:
38.Bd -ragged -offset indent
39.Cd "options DIRFS"
40.Ed
41.Pp
42Actually this driver does not provide a loadable module.
43.Pp
44In
45.Xr fstab 5 :
46.Bd -literal -compact
47/usr/src     /mnt dirfs rw 0 0
48.Sh DESCRIPTION
49.Nm
50was born from the idea of providing an easy way for
51.Xr vkernel 7
52to access host's directories without any sort of configuration as it would be
53needed by NFS for example.
54.Pp
55It runs directly in the vkernel's
56.Xr VFS 9
57code, as any other regular filesystem but it uses syscalls to retrieve the
58information needed for every operation requested.
59.Pp
60It should be noted that when the vkernel is run by a regular user, the
61operations
62.Nm
63can perform on the mounted host directory are bound to the permissions of
64the aforementioned user.
65.Pp
66Multiple
67.Nm
68mounts are allowed.
69.Sh EXAMPLES
70To mount a
71.Nm
72memory file system:
73.Pp
74.Dl "mount -t dirfs /usr/src /mnt"
75.Sh SEE ALSO
76.Xr fstab 5 ,
77.Xr mount_dirfs 8 ,
78.Sh HISTORY
79The
80.Nm
81driver first appeared in
82.Dx 3.5 .
83.Sh AUTHORS
84.An -nosplit
85The
86.Nm
87vkernel implementation was written from the scratch by
88.An Antonio Huete Jimenez Aq Mt tuxillo@quantumachine.net
89.Pp
90Numerous fixes and pointers by
91.An Matthew Dillon Aq Mt dillon@apollo.backplane.com
92.Pp
93This manual page was written by
94.An Antonio Huete Jimenez Aq Mt tuxillo@quantumachine.net
95.Sh BUGS
96Currently there is no locking on file descriptors between the host
97and the vkernel.
98This means that there might be problems with concurrent accesses to the same
99file.
100.Pp
101There is no support for hardlinks in
102.Nm
103yet.
104