1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * fs/kernfs/kernfs-internal.h - kernfs internal header file
4 *
5 * Copyright (c) 2001-3 Patrick Mochel
6 * Copyright (c) 2007 SUSE Linux Products GmbH
7 * Copyright (c) 2007, 2013 Tejun Heo <teheo@suse.de>
8 */
9
10 #ifndef __KERNFS_INTERNAL_H
11 #define __KERNFS_INTERNAL_H
12
13 #include <linux/lockdep.h>
14 #include <linux/fs.h>
15 #include <linux/mutex.h>
16 #include <linux/xattr.h>
17
18 #include <linux/kernfs.h>
19 #include <linux/fs_context.h>
20
21 struct kernfs_iattrs {
22 kuid_t ia_uid;
23 kgid_t ia_gid;
24 struct timespec64 ia_atime;
25 struct timespec64 ia_mtime;
26 struct timespec64 ia_ctime;
27
28 struct simple_xattrs xattrs;
29 };
30
31 /* +1 to avoid triggering overflow warning when negating it */
32 #define KN_DEACTIVATED_BIAS (INT_MIN + 1)
33
34 /* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */
35
36 /**
37 * kernfs_root - find out the kernfs_root a kernfs_node belongs to
38 * @kn: kernfs_node of interest
39 *
40 * Return the kernfs_root @kn belongs to.
41 */
kernfs_root(struct kernfs_node * kn)42 static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn)
43 {
44 /* if parent exists, it's always a dir; otherwise, @sd is a dir */
45 if (kn->parent)
46 kn = kn->parent;
47 return kn->dir.root;
48 }
49
50 /*
51 * mount.c
52 */
53 struct kernfs_super_info {
54 struct super_block *sb;
55
56 /*
57 * The root associated with this super_block. Each super_block is
58 * identified by the root and ns it's associated with.
59 */
60 struct kernfs_root *root;
61
62 /*
63 * Each sb is associated with one namespace tag, currently the
64 * network namespace of the task which mounted this kernfs
65 * instance. If multiple tags become necessary, make the following
66 * an array and compare kernfs_node tag against every entry.
67 */
68 const void *ns;
69
70 /* anchored at kernfs_root->supers, protected by kernfs_mutex */
71 struct list_head node;
72 };
73 #define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info))
74
kernfs_dentry_node(struct dentry * dentry)75 static inline struct kernfs_node *kernfs_dentry_node(struct dentry *dentry)
76 {
77 if (d_really_is_negative(dentry))
78 return NULL;
79 return d_inode(dentry)->i_private;
80 }
81
82 extern const struct super_operations kernfs_sops;
83 extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
84
85 /*
86 * inode.c
87 */
88 extern const struct xattr_handler *kernfs_xattr_handlers[];
89 void kernfs_evict_inode(struct inode *inode);
90 int kernfs_iop_permission(struct inode *inode, int mask);
91 int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr);
92 int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
93 u32 request_mask, unsigned int query_flags);
94 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
95 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
96
97 /*
98 * dir.c
99 */
100 extern struct mutex kernfs_mutex;
101 extern const struct dentry_operations kernfs_dops;
102 extern const struct file_operations kernfs_dir_fops;
103 extern const struct inode_operations kernfs_dir_iops;
104
105 struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
106 void kernfs_put_active(struct kernfs_node *kn);
107 int kernfs_add_one(struct kernfs_node *kn);
108 struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
109 const char *name, umode_t mode,
110 kuid_t uid, kgid_t gid,
111 unsigned flags);
112 struct kernfs_node *kernfs_find_and_get_node_by_ino(struct kernfs_root *root,
113 unsigned int ino);
114
115 /*
116 * file.c
117 */
118 extern const struct file_operations kernfs_file_fops;
119
120 void kernfs_drain_open_files(struct kernfs_node *kn);
121
122 /*
123 * symlink.c
124 */
125 extern const struct inode_operations kernfs_symlink_iops;
126
127 #endif /* __KERNFS_INTERNAL_H */
128