| vfsconf.9 (87252) | vfsconf.9 (87857) |
|---|---|
| 1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as --- 10 unchanged lines hidden (view full) --- 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" | 1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as --- 10 unchanged lines hidden (view full) --- 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" |
| 27.\" $FreeBSD: head/share/man/man9/vfsconf.9 87252 2001-12-03 00:25:04Z alfred $ | 27.\" $FreeBSD: head/share/man/man9/vfsconf.9 87857 2001-12-14 09:11:13Z ru $ |
| 28.\" 29.Dd November 21, 2001 30.Dt VFSCONF 9 31.Os 32.Sh NAME 33.Nm vfsconf 34.Nd "vfs configuration information" 35.Sh SYNOPSIS 36.In sys/param.h 37.In sys/mount.h 38.Ft int 39.Fn vfs_register "struct vfsconf *vfc" 40.Ft int 41.Fn vfs_unregister "struct vfsconf *vfc" 42.Ft int 43.Fn vfs_modevent "module_t mod" "int type" "void *data" 44.Sh DESCRIPTION | 28.\" 29.Dd November 21, 2001 30.Dt VFSCONF 9 31.Os 32.Sh NAME 33.Nm vfsconf 34.Nd "vfs configuration information" 35.Sh SYNOPSIS 36.In sys/param.h 37.In sys/mount.h 38.Ft int 39.Fn vfs_register "struct vfsconf *vfc" 40.Ft int 41.Fn vfs_unregister "struct vfsconf *vfc" 42.Ft int 43.Fn vfs_modevent "module_t mod" "int type" "void *data" 44.Sh DESCRIPTION |
| 45Each filesystem type known to the kernel has a vfsconf structure that contains the | 45Each filesystem type known to the kernel has a 46.Vt vfsconf 47structure that contains the |
| 46information required to create a new mount of that filesystems type. 47.Bd -literal | 48information required to create a new mount of that filesystems type. 49.Bd -literal |
| 48 struct vfsconf { 49 struct vfsops *vfc_vfsops; /* filesystem operations vector */ 50 char vfc_name[MFSNAMELEN]; /* filesystem type name */ 51 int vfc_typenum; /* historic filesystem type number */ 52 int vfc_refcount; /* number mounted of this type */ 53 int vfc_flags; /* permanent flags */ 54 struct vfsconf *vfc_next; /* next in list */ 55 }; 56 | 50struct vfsconf { 51 struct vfsops *vfc_vfsops; /* filesystem operations vector */ 52 char vfc_name[MFSNAMELEN]; /* filesystem type name */ 53 int vfc_typenum; /* historic filesystem type number */ 54 int vfc_refcount; /* number mounted of this type */ 55 int vfc_flags; /* permanent flags */ 56 struct vfsconf *vfc_next; /* next in list */ 57}; |
| 57.Ed | 58.Ed |
| 58When a new filesystem is mounted 59.Fn vfs_mount 60does a lookup of the vfcconf structure by its name, and if it is not already registered, | 59.Pp 60When a new filesystem is mounted, 61.Xr vfs_mount 9 62does a lookup of the 63.Vt vfsconf 64structure by its name, and if it is not already registered, |
| 61attempts to load a kernel module for it. | 65attempts to load a kernel module for it. |
| 62The filesystem operations for the new mount point are taken from vfc_vfsops, and mnt_vfc 63in the mount structure is made to point directly at the vfcconf structure for the | 66The filesystem operations for the new mount point are taken from 67.Va vfc_vfsops , 68and 69.Va mnt_vfc 70in the 71.Vt mount 72structure is made to point directly at the 73.Vt vfsconf 74structure for the |
| 64filesystem type. | 75filesystem type. |
| 65The filesystem type number is taken from vfs_typenum which was assigned in | 76The filesystem type number is taken from 77.Va vfc_typenum 78which was assigned in |
| 66.Fn vfs_register , | 79.Fn vfs_register , |
| 67and the mount flags are taken from a mask of vfc_flags. 68Each time a filesystem of a given type is mounted vfc_refcount is incremented. | 80and the mount flags are taken from a mask of 81.Va vfc_flags . 82Each time a filesystem of a given type is mounted, 83.Va vfc_refcount 84is incremented. |
| 69.Pp 70.Fn vfs_register | 85.Pp 86.Fn vfs_register |
| 71takes a new vfsconf structure and adds it to the list of existing filesystems. 72If the type has not already been registered it is initialize by calling the | 87takes a new 88.Vt vfsconf 89structure and adds it to the list of existing filesystems. 90If the type has not already been registered, it is initialized by calling the |
| 73.Fn vfs_init 74function in the filesystem operations vector. 75.Fn vfs_register 76also updates the oid's of any sysctl nodes for this filesystem type 77to be the same as the newly assigned type number. 78.Pp 79.Fn vfs_unregister 80unlinks 81.Fa vfc 82from the list of registered filesystem types if there are currently no mounted instances. 83If the 84.Fn vfs_uninit | 91.Fn vfs_init 92function in the filesystem operations vector. 93.Fn vfs_register 94also updates the oid's of any sysctl nodes for this filesystem type 95to be the same as the newly assigned type number. 96.Pp 97.Fn vfs_unregister 98unlinks 99.Fa vfc 100from the list of registered filesystem types if there are currently no mounted instances. 101If the 102.Fn vfs_uninit |
| 85function in the filesystems initialization vector is defined it is called. | 103function in the filesystems initialization vector is defined, it is called. |
| 86.Pp 87.Fn vfs_modevent 88is registered by 89.Fn VFS_SET 90to handle the loading and unloading of filesystem kernel modules. 91In the case of | 104.Pp 105.Fn vfs_modevent 106is registered by 107.Fn VFS_SET 108to handle the loading and unloading of filesystem kernel modules. 109In the case of |
| 92.Dv MOD_LOAD | 110.Dv MOD_LOAD , |
| 93.Fn vfs_register 94is called. 95In the case of | 111.Fn vfs_register 112is called. 113In the case of |
| 96.Dv MOD_UNLOAD | 114.Dv MOD_UNLOAD , |
| 97.Fn vfs_unregister 98is called. 99.Sh RETURN VALUES 100.Fn vfs_register 101returns 0 if successful; otherwise, | 115.Fn vfs_unregister 116is called. 117.Sh RETURN VALUES 118.Fn vfs_register 119returns 0 if successful; otherwise, |
| 102.Dv EEXIST | 120.Er EEXIST |
| 103is returned indicating that the filesystem type has already been registered. 104.Pp 105.Fn vfs_unregister 106returns 0 if successful. | 121is returned indicating that the filesystem type has already been registered. 122.Pp 123.Fn vfs_unregister 124returns 0 if successful. |
| 107If no vfsconf entry can be found matching the name in | 125If no 126.Vt vfsconf 127entry can be found matching the name in |
| 108.Fa vfc , | 128.Fa vfc , |
| 109.Dv EINVAL | 129.Er EINVAL |
| 110is returned. | 130is returned. |
| 111If the reference count of mounted instances of the filesystem type is not zero 112.Dv EBUSY | 131If the reference count of mounted instances of the filesystem type is not zero, 132.Er EBUSY |
| 113is returned. 114If 115.Fn vfs_uninit | 133is returned. 134If 135.Fn vfs_uninit |
| 116is called any errors it returns will be returned by | 136is called, any errors it returns will be returned by |
| 117.Fn vfs_unregister . 118.Pp 119.Fn vfs_modevent 120returns the result of the call to 121.Fn vfs_register 122or | 137.Fn vfs_unregister . 138.Pp 139.Fn vfs_modevent 140returns the result of the call to 141.Fn vfs_register 142or |
| 123.Fn vfs_unregister | 143.Fn vfs_unregister , |
| 124whatever the case. 125.Sh SEE ALSO | 144whatever the case. 145.Sh SEE ALSO |
| 146.Xr vfs_mount 9 , |
|
| 126.Xr vfs_rootmountalloc 9 , | 147.Xr vfs_rootmountalloc 9 , |
| 127.Xr vfs_mount , | |
| 128.Xr VFS_SET 9 129.Sh AUTHORS 130This man page was written by 131.An Chad David Aq davidc@acns.ab.ca . | 148.Xr VFS_SET 9 149.Sh AUTHORS 150This man page was written by 151.An Chad David Aq davidc@acns.ab.ca . |