1/* -*- mode: c; c-basic-offset:8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * configfs_internal.h - Internal stuff for configfs
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public
17 * License along with this program; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 021110-1307, USA.
20 *
21 * Based on sysfs:
22 * 	sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
23 *
24 * configfs Copyright (C) 2005 Oracle.  All rights reserved.
25 */
26
27#include <linux/slab.h>
28#include <linux/list.h>
29
30struct configfs_dirent {
31	atomic_t		s_count;
32	struct list_head	s_sibling;
33	struct list_head	s_children;
34	struct list_head	s_links;
35	void 			* s_element;
36	int			s_type;
37	umode_t			s_mode;
38	struct dentry		* s_dentry;
39	struct iattr		* s_iattr;
40};
41
42#define CONFIGFS_ROOT		0x0001
43#define CONFIGFS_DIR		0x0002
44#define CONFIGFS_ITEM_ATTR 	0x0004
45#define CONFIGFS_ITEM_LINK 	0x0020
46#define CONFIGFS_USET_DIR	0x0040
47#define CONFIGFS_USET_DEFAULT	0x0080
48#define CONFIGFS_USET_DROPPING	0x0100
49#define CONFIGFS_NOT_PINNED	(CONFIGFS_ITEM_ATTR)
50
51extern struct vfsmount * configfs_mount;
52extern struct kmem_cache *configfs_dir_cachep;
53
54extern int configfs_is_root(struct config_item *item);
55
56extern struct inode * configfs_new_inode(mode_t mode, struct configfs_dirent *);
57extern int configfs_create(struct dentry *, int mode, int (*init)(struct inode *));
58
59extern int configfs_create_file(struct config_item *, const struct configfs_attribute *);
60extern int configfs_make_dirent(struct configfs_dirent *,
61				struct dentry *, void *, umode_t, int);
62
63extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int);
64extern void configfs_hash_and_remove(struct dentry * dir, const char * name);
65
66extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);
67extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent);
68extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr);
69
70extern int configfs_pin_fs(void);
71extern void configfs_release_fs(void);
72
73extern struct rw_semaphore configfs_rename_sem;
74extern struct super_block * configfs_sb;
75extern const struct file_operations configfs_dir_operations;
76extern const struct file_operations configfs_file_operations;
77extern const struct file_operations bin_fops;
78extern const struct inode_operations configfs_dir_inode_operations;
79extern const struct inode_operations configfs_symlink_inode_operations;
80
81extern int configfs_symlink(struct inode *dir, struct dentry *dentry,
82			    const char *symname);
83extern int configfs_unlink(struct inode *dir, struct dentry *dentry);
84
85struct configfs_symlink {
86	struct list_head sl_list;
87	struct config_item *sl_target;
88};
89
90extern int configfs_create_link(struct configfs_symlink *sl,
91				struct dentry *parent,
92				struct dentry *dentry);
93
94static inline struct config_item * to_item(struct dentry * dentry)
95{
96	struct configfs_dirent * sd = dentry->d_fsdata;
97	return ((struct config_item *) sd->s_element);
98}
99
100static inline struct configfs_attribute * to_attr(struct dentry * dentry)
101{
102	struct configfs_dirent * sd = dentry->d_fsdata;
103	return ((struct configfs_attribute *) sd->s_element);
104}
105
106static inline struct config_item *configfs_get_config_item(struct dentry *dentry)
107{
108	struct config_item * item = NULL;
109
110	spin_lock(&dcache_lock);
111	if (!d_unhashed(dentry)) {
112		struct configfs_dirent * sd = dentry->d_fsdata;
113		if (sd->s_type & CONFIGFS_ITEM_LINK) {
114			struct configfs_symlink * sl = sd->s_element;
115			item = config_item_get(sl->sl_target);
116		} else
117			item = config_item_get(sd->s_element);
118	}
119	spin_unlock(&dcache_lock);
120
121	return item;
122}
123
124static inline void release_configfs_dirent(struct configfs_dirent * sd)
125{
126	if (!(sd->s_type & CONFIGFS_ROOT)) {
127		kfree(sd->s_iattr);
128		kmem_cache_free(configfs_dir_cachep, sd);
129	}
130}
131
132static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd)
133{
134	if (sd) {
135		WARN_ON(!atomic_read(&sd->s_count));
136		atomic_inc(&sd->s_count);
137	}
138	return sd;
139}
140
141static inline void configfs_put(struct configfs_dirent * sd)
142{
143	WARN_ON(!atomic_read(&sd->s_count));
144	if (atomic_dec_and_test(&sd->s_count))
145		release_configfs_dirent(sd);
146}
147