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/rwsem.h> |
17 | #include <linux/xattr.h> |
18 | |
19 | #include <linux/kernfs.h> |
20 | #include <linux/fs_context.h> |
21 | |
22 | struct kernfs_iattrs { |
23 | kuid_t ia_uid; |
24 | kgid_t ia_gid; |
25 | struct timespec64 ia_atime; |
26 | struct timespec64 ia_mtime; |
27 | struct timespec64 ia_ctime; |
28 | |
29 | struct simple_xattrs xattrs; |
30 | atomic_t nr_user_xattrs; |
31 | atomic_t user_xattr_size; |
32 | }; |
33 | |
34 | struct kernfs_root { |
35 | /* published fields */ |
36 | struct kernfs_node *kn; |
37 | unsigned int flags; /* KERNFS_ROOT_* flags */ |
38 | |
39 | /* private fields, do not use outside kernfs proper */ |
40 | struct idr ino_idr; |
41 | u32 last_id_lowbits; |
42 | u32 id_highbits; |
43 | struct kernfs_syscall_ops *syscall_ops; |
44 | |
45 | /* list of kernfs_super_info of this root, protected by kernfs_rwsem */ |
46 | struct list_head supers; |
47 | |
48 | wait_queue_head_t deactivate_waitq; |
49 | struct rw_semaphore kernfs_rwsem; |
50 | struct rw_semaphore kernfs_iattr_rwsem; |
51 | struct rw_semaphore kernfs_supers_rwsem; |
52 | }; |
53 | |
54 | /* +1 to avoid triggering overflow warning when negating it */ |
55 | #define KN_DEACTIVATED_BIAS (INT_MIN + 1) |
56 | |
57 | /* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */ |
58 | |
59 | /** |
60 | * kernfs_root - find out the kernfs_root a kernfs_node belongs to |
61 | * @kn: kernfs_node of interest |
62 | * |
63 | * Return: the kernfs_root @kn belongs to. |
64 | */ |
65 | static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn) |
66 | { |
67 | /* if parent exists, it's always a dir; otherwise, @sd is a dir */ |
68 | if (kn->parent) |
69 | kn = kn->parent; |
70 | return kn->dir.root; |
71 | } |
72 | |
73 | /* |
74 | * mount.c |
75 | */ |
76 | struct kernfs_super_info { |
77 | struct super_block *sb; |
78 | |
79 | /* |
80 | * The root associated with this super_block. Each super_block is |
81 | * identified by the root and ns it's associated with. |
82 | */ |
83 | struct kernfs_root *root; |
84 | |
85 | /* |
86 | * Each sb is associated with one namespace tag, currently the |
87 | * network namespace of the task which mounted this kernfs |
88 | * instance. If multiple tags become necessary, make the following |
89 | * an array and compare kernfs_node tag against every entry. |
90 | */ |
91 | const void *ns; |
92 | |
93 | /* anchored at kernfs_root->supers, protected by kernfs_rwsem */ |
94 | struct list_head node; |
95 | }; |
96 | #define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info)) |
97 | |
98 | static inline struct kernfs_node *kernfs_dentry_node(struct dentry *dentry) |
99 | { |
100 | if (d_really_is_negative(dentry)) |
101 | return NULL; |
102 | return d_inode(dentry)->i_private; |
103 | } |
104 | |
105 | static inline void kernfs_set_rev(struct kernfs_node *parent, |
106 | struct dentry *dentry) |
107 | { |
108 | dentry->d_time = parent->dir.rev; |
109 | } |
110 | |
111 | static inline void kernfs_inc_rev(struct kernfs_node *parent) |
112 | { |
113 | parent->dir.rev++; |
114 | } |
115 | |
116 | static inline bool kernfs_dir_changed(struct kernfs_node *parent, |
117 | struct dentry *dentry) |
118 | { |
119 | if (parent->dir.rev != dentry->d_time) |
120 | return true; |
121 | return false; |
122 | } |
123 | |
124 | extern const struct super_operations kernfs_sops; |
125 | extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache; |
126 | |
127 | /* |
128 | * inode.c |
129 | */ |
130 | extern const struct xattr_handler * const kernfs_xattr_handlers[]; |
131 | void kernfs_evict_inode(struct inode *inode); |
132 | int kernfs_iop_permission(struct mnt_idmap *idmap, |
133 | struct inode *inode, int mask); |
134 | int kernfs_iop_setattr(struct mnt_idmap *idmap, struct dentry *dentry, |
135 | struct iattr *iattr); |
136 | int kernfs_iop_getattr(struct mnt_idmap *idmap, |
137 | const struct path *path, struct kstat *stat, |
138 | u32 request_mask, unsigned int query_flags); |
139 | ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size); |
140 | int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr); |
141 | |
142 | /* |
143 | * dir.c |
144 | */ |
145 | extern const struct dentry_operations kernfs_dops; |
146 | extern const struct file_operations kernfs_dir_fops; |
147 | extern const struct inode_operations kernfs_dir_iops; |
148 | |
149 | struct kernfs_node *kernfs_get_active(struct kernfs_node *kn); |
150 | void kernfs_put_active(struct kernfs_node *kn); |
151 | int kernfs_add_one(struct kernfs_node *kn); |
152 | struct kernfs_node *kernfs_new_node(struct kernfs_node *parent, |
153 | const char *name, umode_t mode, |
154 | kuid_t uid, kgid_t gid, |
155 | unsigned flags); |
156 | |
157 | /* |
158 | * file.c |
159 | */ |
160 | extern const struct file_operations kernfs_file_fops; |
161 | |
162 | bool kernfs_should_drain_open_files(struct kernfs_node *kn); |
163 | void kernfs_drain_open_files(struct kernfs_node *kn); |
164 | |
165 | /* |
166 | * symlink.c |
167 | */ |
168 | extern const struct inode_operations kernfs_symlink_iops; |
169 | |
170 | /* |
171 | * kernfs locks |
172 | */ |
173 | extern struct kernfs_global_locks *kernfs_locks; |
174 | #endif /* __KERNFS_INTERNAL_H */ |
175 | |