xref: /netbsd-src/lib/libpuffs/puffs_node.3 (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1.\"	$NetBSD: puffs_node.3,v 1.3 2007/12/01 19:18:50 wiz Exp $
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3.\" Copyright (c) 2007 Antti Kantee.  All rights reserved.
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26.Dd June 24, 2007
27.Dt PUFFS_NODE 3
28.Os
29.Sh NAME
30.Nm puffs_node
31.Nd puffs node routines
32.Sh LIBRARY
33.Lb libpuffs
34.Sh SYNOPSIS
35.In puffs.h
36.Ft struct puffs_node *
37.Fn puffs_pn_new "struct puffs_usermount *pu" "void *priv"
38.Ft void *
39.Fo puffs_nodewalk_fn
40.Fa "struct puffs_usermount *pu" "struct puffs_node *pn" "void *arg"
41.Fc
42.Ft void *
43.Fo puffs_pn_nodewalk
44.Fa "struct puffs_usermount *pu" "puffs_nodewalk_fn nwfn" "void *arg"
45.Fc
46.Ft void
47.Fn puffs_pn_remove "struct puffs_node *pn"
48.Ft void
49.Fn puffs_pn_put "struct puffs_node *pn"
50.Sh DESCRIPTION
51.Em IMPORTANT NOTE!
52This document describes interfaces which are not yet guaranteed to be
53stable.
54In case you update your system sources, please recompile everything
55and fix compilation errors.
56If your sources are out-of-sync, incorrect operation may result.
57The interfaces in this document will most likely be hugely simplified
58in later versions or made transparent to the implementation.
59.Pp
60.Em MORE IMPORTANT STUFF!
61It should especially be noted, that it is yet completely unsure, how
62much of the internals contents of
63.Vt struct puffs_node
64will be exposed to file systems in the end.
65.Pp
66.Bl -tag -width xxxx
67.It Fn puffs_pn_new pu priv
68Create a new node and attach it to the mountpoint
69.Ar pu .
70The argument
71.Ar priv
72can be used for associating file system specific data with the new
73node and will not be accessed by puffs.
74.It Fn puffs_nodewalk_fn pu pn arg
75A callback for
76.Fn puffs_nodewalk .
77The list of nodes is iterated in the argument
78.Ar pn
79and the argument
80.Ar arg
81is the argument given to
82.Fn puffs_nodewalk .
83.It Fn puffs_nodewalk pu nwfn arg
84Walk all nodes associted with the mountpoint
85.Ar pu
86and call
87.Fn nwfn
88for them.
89The walk is aborted if
90.Fn puffs_nodewalk_fn
91returns a value which is not
92.Dv NULL .
93This value is also returned this function.
94In case the whole set of nodes is traversed,
95.Dv NULL
96is returned.
97This function is useful for example in handling the
98.Fn puffs_fs_sync
99callback, when cached data for every node should be flushed to stable
100storage.
101.It Fn puffs_pn_remove pn
102Signal that a node has been removed from the file system, but do not
103yet release resources associated with the node.
104This will prevent the nodewalk functions from accessing the node.
105If necessary, this is usually called from
106.Fn puffs_node_remove
107and
108.Fn puffs_node_rmdir .
109.It Fn puffs_pn_put pn
110Free all resources associated with node
111.Ar pn .
112This is typically called from
113.Fn puffs_node_reclaim .
114.Pp
115.El
116.Sh SEE ALSO
117.Xr puffs 3
118