1/*
 2 * V9FS FID Management
 3 *
 4 *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
 5 *
 6 *  This program is free software; you can redistribute it and/or modify
 7 *  it under the terms of the GNU General Public License version 2
 8 *  as published by the Free Software Foundation.
 9 *
10 *  This program is distributed in the hope that it will be useful,
11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 *  GNU General Public License for more details.
14 *
15 *  You should have received a copy of the GNU General Public License
16 *  along with this program; if not, write to:
17 *  Free Software Foundation
18 *  51 Franklin Street, Fifth Floor
19 *  Boston, MA  02111-1301  USA
20 *
21 */
22#ifndef FS_9P_FID_H
23#define FS_9P_FID_H
24#include <linux/list.h>
25
26/**
27 * struct v9fs_dentry - 9p private data stored in dentry d_fsdata
28 * @lock: protects the fidlist
29 * @fidlist: list of FIDs currently associated with this dentry
30 *
31 * This structure defines the 9p private data associated with
32 * a particular dentry.  In particular, this private data is used
33 * to lookup which 9P FID handle should be used for a particular VFS
34 * operation.  FID handles are associated with dentries instead of
35 * inodes in order to more closely map functionality to the Plan 9
36 * expected behavior for FID reclaimation and tracking.
37 *
38 * See Also: Mapping FIDs to Linux VFS model in
39 * Design and Implementation of the Linux 9P File System documentation
40 */
41struct v9fs_dentry {
42	spinlock_t lock; /* protect fidlist */
43	struct list_head fidlist;
44};
45
46struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
47struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
48int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
49struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
50#endif