xref: /linux-6.15/include/linux/proc_fs.h (revision fa10fed3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * The proc filesystem constants/structures
4  */
5 #ifndef _LINUX_PROC_FS_H
6 #define _LINUX_PROC_FS_H
7 
8 #include <linux/compiler.h>
9 #include <linux/types.h>
10 #include <linux/fs.h>
11 
12 struct proc_dir_entry;
13 struct seq_file;
14 struct seq_operations;
15 
16 enum {
17 	/*
18 	 * All /proc entries using this ->proc_ops instance are never removed.
19 	 *
20 	 * If in doubt, ignore this flag.
21 	 */
22 #ifdef MODULE
23 	PROC_ENTRY_PERMANENT = 0U,
24 #else
25 	PROC_ENTRY_PERMANENT = 1U << 0,
26 #endif
27 };
28 
29 struct proc_ops {
30 	unsigned int proc_flags;
31 	int	(*proc_open)(struct inode *, struct file *);
32 	ssize_t	(*proc_read)(struct file *, char __user *, size_t, loff_t *);
33 	ssize_t	(*proc_write)(struct file *, const char __user *, size_t, loff_t *);
34 	loff_t	(*proc_lseek)(struct file *, loff_t, int);
35 	int	(*proc_release)(struct inode *, struct file *);
36 	__poll_t (*proc_poll)(struct file *, struct poll_table_struct *);
37 	long	(*proc_ioctl)(struct file *, unsigned int, unsigned long);
38 #ifdef CONFIG_COMPAT
39 	long	(*proc_compat_ioctl)(struct file *, unsigned int, unsigned long);
40 #endif
41 	int	(*proc_mmap)(struct file *, struct vm_area_struct *);
42 	unsigned long (*proc_get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
43 } __randomize_layout;
44 
45 /* definitions for hide_pid field */
46 enum {
47 	HIDEPID_OFF	  = 0,
48 	HIDEPID_NO_ACCESS = 1,
49 	HIDEPID_INVISIBLE = 2,
50 };
51 
52 struct proc_fs_info {
53 	struct pid_namespace *pid_ns;
54 	struct dentry *proc_self;        /* For /proc/self */
55 	struct dentry *proc_thread_self; /* For /proc/thread-self */
56 	kgid_t pid_gid;
57 	int hide_pid;
58 };
59 
60 static inline struct proc_fs_info *proc_sb_info(struct super_block *sb)
61 {
62 	return sb->s_fs_info;
63 }
64 
65 #ifdef CONFIG_PROC_FS
66 
67 typedef int (*proc_write_t)(struct file *, char *, size_t);
68 
69 extern void proc_root_init(void);
70 extern void proc_flush_pid(struct pid *);
71 
72 extern struct proc_dir_entry *proc_symlink(const char *,
73 		struct proc_dir_entry *, const char *);
74 extern struct proc_dir_entry *proc_mkdir(const char *, struct proc_dir_entry *);
75 extern struct proc_dir_entry *proc_mkdir_data(const char *, umode_t,
76 					      struct proc_dir_entry *, void *);
77 extern struct proc_dir_entry *proc_mkdir_mode(const char *, umode_t,
78 					      struct proc_dir_entry *);
79 struct proc_dir_entry *proc_create_mount_point(const char *name);
80 
81 struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode,
82 		struct proc_dir_entry *parent, const struct seq_operations *ops,
83 		unsigned int state_size, void *data);
84 #define proc_create_seq_data(name, mode, parent, ops, data) \
85 	proc_create_seq_private(name, mode, parent, ops, 0, data)
86 #define proc_create_seq(name, mode, parent, ops) \
87 	proc_create_seq_private(name, mode, parent, ops, 0, NULL)
88 struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
89 		struct proc_dir_entry *parent,
90 		int (*show)(struct seq_file *, void *), void *data);
91 #define proc_create_single(name, mode, parent, show) \
92 	proc_create_single_data(name, mode, parent, show, NULL)
93 
94 extern struct proc_dir_entry *proc_create_data(const char *, umode_t,
95 					       struct proc_dir_entry *,
96 					       const struct proc_ops *,
97 					       void *);
98 
99 struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct proc_ops *proc_ops);
100 extern void proc_set_size(struct proc_dir_entry *, loff_t);
101 extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t);
102 extern void *PDE_DATA(const struct inode *);
103 extern void *proc_get_parent_data(const struct inode *);
104 extern void proc_remove(struct proc_dir_entry *);
105 extern void remove_proc_entry(const char *, struct proc_dir_entry *);
106 extern int remove_proc_subtree(const char *, struct proc_dir_entry *);
107 
108 struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
109 		struct proc_dir_entry *parent, const struct seq_operations *ops,
110 		unsigned int state_size, void *data);
111 #define proc_create_net(name, mode, parent, ops, state_size) \
112 	proc_create_net_data(name, mode, parent, ops, state_size, NULL)
113 struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
114 		struct proc_dir_entry *parent,
115 		int (*show)(struct seq_file *, void *), void *data);
116 struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode,
117 						  struct proc_dir_entry *parent,
118 						  const struct seq_operations *ops,
119 						  proc_write_t write,
120 						  unsigned int state_size, void *data);
121 struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mode,
122 						    struct proc_dir_entry *parent,
123 						    int (*show)(struct seq_file *, void *),
124 						    proc_write_t write,
125 						    void *data);
126 extern struct pid *tgid_pidfd_to_pid(const struct file *file);
127 
128 #ifdef CONFIG_PROC_PID_ARCH_STATUS
129 /*
130  * The architecture which selects CONFIG_PROC_PID_ARCH_STATUS must
131  * provide proc_pid_arch_status() definition.
132  */
133 int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns,
134 			struct pid *pid, struct task_struct *task);
135 #endif /* CONFIG_PROC_PID_ARCH_STATUS */
136 
137 #else /* CONFIG_PROC_FS */
138 
139 static inline void proc_root_init(void)
140 {
141 }
142 
143 static inline void proc_flush_pid(struct pid *pid)
144 {
145 }
146 
147 static inline struct proc_dir_entry *proc_symlink(const char *name,
148 		struct proc_dir_entry *parent,const char *dest) { return NULL;}
149 static inline struct proc_dir_entry *proc_mkdir(const char *name,
150 	struct proc_dir_entry *parent) {return NULL;}
151 static inline struct proc_dir_entry *proc_create_mount_point(const char *name) { return NULL; }
152 static inline struct proc_dir_entry *proc_mkdir_data(const char *name,
153 	umode_t mode, struct proc_dir_entry *parent, void *data) { return NULL; }
154 static inline struct proc_dir_entry *proc_mkdir_mode(const char *name,
155 	umode_t mode, struct proc_dir_entry *parent) { return NULL; }
156 #define proc_create_seq_private(name, mode, parent, ops, size, data) ({NULL;})
157 #define proc_create_seq_data(name, mode, parent, ops, data) ({NULL;})
158 #define proc_create_seq(name, mode, parent, ops) ({NULL;})
159 #define proc_create_single(name, mode, parent, show) ({NULL;})
160 #define proc_create_single_data(name, mode, parent, show, data) ({NULL;})
161 #define proc_create(name, mode, parent, proc_ops) ({NULL;})
162 #define proc_create_data(name, mode, parent, proc_ops, data) ({NULL;})
163 
164 static inline void proc_set_size(struct proc_dir_entry *de, loff_t size) {}
165 static inline void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) {}
166 static inline void *PDE_DATA(const struct inode *inode) {BUG(); return NULL;}
167 static inline void *proc_get_parent_data(const struct inode *inode) { BUG(); return NULL; }
168 
169 static inline void proc_remove(struct proc_dir_entry *de) {}
170 #define remove_proc_entry(name, parent) do {} while (0)
171 static inline int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) { return 0; }
172 
173 #define proc_create_net_data(name, mode, parent, ops, state_size, data) ({NULL;})
174 #define proc_create_net(name, mode, parent, state_size, ops) ({NULL;})
175 #define proc_create_net_single(name, mode, parent, show, data) ({NULL;})
176 
177 static inline struct pid *tgid_pidfd_to_pid(const struct file *file)
178 {
179 	return ERR_PTR(-EBADF);
180 }
181 
182 #endif /* CONFIG_PROC_FS */
183 
184 struct net;
185 
186 static inline struct proc_dir_entry *proc_net_mkdir(
187 	struct net *net, const char *name, struct proc_dir_entry *parent)
188 {
189 	return proc_mkdir_data(name, 0, parent, net);
190 }
191 
192 struct ns_common;
193 int open_related_ns(struct ns_common *ns,
194 		   struct ns_common *(*get_ns)(struct ns_common *ns));
195 
196 /* get the associated pid namespace for a file in procfs */
197 static inline struct pid_namespace *proc_pid_ns(const struct inode *inode)
198 {
199 	return proc_sb_info(inode->i_sb)->pid_ns;
200 }
201 
202 #endif /* _LINUX_PROC_FS_H */
203