xref: /linux-6.15/include/linux/proc_fs.h (revision 2b8232ce)
1 #ifndef _LINUX_PROC_FS_H
2 #define _LINUX_PROC_FS_H
3 
4 #include <linux/slab.h>
5 #include <linux/fs.h>
6 #include <linux/spinlock.h>
7 #include <linux/magic.h>
8 #include <asm/atomic.h>
9 
10 struct net;
11 struct completion;
12 
13 /*
14  * The proc filesystem constants/structures
15  */
16 
17 /*
18  * Offset of the first process in the /proc root directory..
19  */
20 #define FIRST_PROCESS_ENTRY 256
21 
22 
23 /*
24  * We always define these enumerators
25  */
26 
27 enum {
28 	PROC_ROOT_INO = 1,
29 };
30 
31 /*
32  * This is not completely implemented yet. The idea is to
33  * create an in-memory tree (like the actual /proc filesystem
34  * tree) of these proc_dir_entries, so that we can dynamically
35  * add new files to /proc.
36  *
37  * The "next" pointer creates a linked list of one /proc directory,
38  * while parent/subdir create the directory structure (every
39  * /proc file has a parent, but "subdir" is NULL for all
40  * non-directory entries).
41  *
42  * "get_info" is called at "read", while "owner" is used to protect module
43  * from unloading while proc_dir_entry is in use
44  */
45 
46 typedef	int (read_proc_t)(char *page, char **start, off_t off,
47 			  int count, int *eof, void *data);
48 typedef	int (write_proc_t)(struct file *file, const char __user *buffer,
49 			   unsigned long count, void *data);
50 typedef int (get_info_t)(char *, char **, off_t, int);
51 
52 struct proc_dir_entry {
53 	unsigned int low_ino;
54 	unsigned short namelen;
55 	const char *name;
56 	mode_t mode;
57 	nlink_t nlink;
58 	uid_t uid;
59 	gid_t gid;
60 	loff_t size;
61 	const struct inode_operations *proc_iops;
62 	/*
63 	 * NULL ->proc_fops means "PDE is going away RSN" or
64 	 * "PDE is just created". In either case, e.g. ->read_proc won't be
65 	 * called because it's too late or too early, respectively.
66 	 *
67 	 * If you're allocating ->proc_fops dynamically, save a pointer
68 	 * somewhere.
69 	 */
70 	const struct file_operations *proc_fops;
71 	get_info_t *get_info;
72 	struct module *owner;
73 	struct proc_dir_entry *next, *parent, *subdir;
74 	void *data;
75 	read_proc_t *read_proc;
76 	write_proc_t *write_proc;
77 	atomic_t count;		/* use count */
78 	int deleted;		/* delete flag */
79 	int pde_users;	/* number of callers into module in progress */
80 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
81 	struct completion *pde_unload_completion;
82 };
83 
84 struct kcore_list {
85 	struct kcore_list *next;
86 	unsigned long addr;
87 	size_t size;
88 };
89 
90 struct vmcore {
91 	struct list_head list;
92 	unsigned long long paddr;
93 	unsigned long long size;
94 	loff_t offset;
95 };
96 
97 #ifdef CONFIG_PROC_FS
98 
99 extern struct proc_dir_entry proc_root;
100 extern struct proc_dir_entry *proc_root_fs;
101 extern struct proc_dir_entry *proc_bus;
102 extern struct proc_dir_entry *proc_root_driver;
103 extern struct proc_dir_entry *proc_root_kcore;
104 
105 extern spinlock_t proc_subdir_lock;
106 
107 extern void proc_root_init(void);
108 extern void proc_misc_init(void);
109 
110 struct mm_struct;
111 
112 void proc_flush_task(struct task_struct *task);
113 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);
114 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir);
115 unsigned long task_vsize(struct mm_struct *);
116 int task_statm(struct mm_struct *, int *, int *, int *, int *);
117 char *task_mem(struct mm_struct *, char *);
118 void clear_refs_smap(struct mm_struct *mm);
119 
120 struct proc_dir_entry *de_get(struct proc_dir_entry *de);
121 void de_put(struct proc_dir_entry *de);
122 
123 extern struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
124 						struct proc_dir_entry *parent);
125 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
126 
127 extern struct vfsmount *proc_mnt;
128 extern int proc_fill_super(struct super_block *,void *,int);
129 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
130 
131 /*
132  * These are generic /proc routines that use the internal
133  * "struct proc_dir_entry" tree to traverse the filesystem.
134  *
135  * The /proc root directory has extended versions to take care
136  * of the /proc/<pid> subdirectories.
137  */
138 extern int proc_readdir(struct file *, void *, filldir_t);
139 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
140 
141 extern const struct file_operations proc_kcore_operations;
142 extern const struct file_operations proc_kmsg_operations;
143 extern const struct file_operations ppc_htab_operations;
144 
145 /*
146  * proc_tty.c
147  */
148 struct tty_driver;
149 extern void proc_tty_init(void);
150 extern void proc_tty_register_driver(struct tty_driver *driver);
151 extern void proc_tty_unregister_driver(struct tty_driver *driver);
152 
153 /*
154  * proc_devtree.c
155  */
156 #ifdef CONFIG_PROC_DEVICETREE
157 struct device_node;
158 struct property;
159 extern void proc_device_tree_init(void);
160 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
161 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
162 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
163 					 struct property *prop);
164 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
165 					 struct property *newprop,
166 					 struct property *oldprop);
167 #endif /* CONFIG_PROC_DEVICETREE */
168 
169 extern struct proc_dir_entry *proc_symlink(const char *,
170 		struct proc_dir_entry *, const char *);
171 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
172 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
173 			struct proc_dir_entry *parent);
174 
175 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
176 	mode_t mode, struct proc_dir_entry *base,
177 	read_proc_t *read_proc, void * data)
178 {
179 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
180 	if (res) {
181 		res->read_proc=read_proc;
182 		res->data=data;
183 	}
184 	return res;
185 }
186 
187 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
188 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
189 {
190 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
191 	if (res) res->get_info=get_info;
192 	return res;
193 }
194 
195 extern struct proc_dir_entry *proc_net_create(struct net *net,
196 	const char *name, mode_t mode, get_info_t *get_info);
197 extern struct proc_dir_entry *proc_net_fops_create(struct net *net,
198 	const char *name, mode_t mode, const struct file_operations *fops);
199 extern void proc_net_remove(struct net *net, const char *name);
200 
201 #else
202 
203 #define proc_root_driver NULL
204 #define proc_bus NULL
205 
206 #define proc_net_fops_create(net, name, mode, fops)  ({ (void)(mode), NULL; })
207 #define proc_net_create(net, name, mode, info)	({ (void)(mode), NULL; })
208 static inline void proc_net_remove(struct net *net, const char *name) {}
209 
210 static inline void proc_flush_task(struct task_struct *task) { }
211 
212 static inline struct proc_dir_entry *create_proc_entry(const char *name,
213 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
214 
215 #define remove_proc_entry(name, parent) do {} while (0)
216 
217 static inline struct proc_dir_entry *proc_symlink(const char *name,
218 		struct proc_dir_entry *parent,const char *dest) {return NULL;}
219 static inline struct proc_dir_entry *proc_mkdir(const char *name,
220 	struct proc_dir_entry *parent) {return NULL;}
221 
222 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
223 	mode_t mode, struct proc_dir_entry *base,
224 	read_proc_t *read_proc, void * data) { return NULL; }
225 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
226 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
227 	{ return NULL; }
228 
229 struct tty_driver;
230 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
231 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
232 
233 extern struct proc_dir_entry proc_root;
234 
235 #endif /* CONFIG_PROC_FS */
236 
237 #if !defined(CONFIG_PROC_KCORE)
238 static inline void kclist_add(struct kcore_list *new, void *addr, size_t size)
239 {
240 }
241 #else
242 extern void kclist_add(struct kcore_list *, void *, size_t);
243 #endif
244 
245 union proc_op {
246 	int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
247 	int (*proc_read)(struct task_struct *task, char *page);
248 };
249 
250 struct proc_inode {
251 	struct pid *pid;
252 	int fd;
253 	union proc_op op;
254 	struct proc_dir_entry *pde;
255 	struct inode vfs_inode;
256 };
257 
258 static inline struct proc_inode *PROC_I(const struct inode *inode)
259 {
260 	return container_of(inode, struct proc_inode, vfs_inode);
261 }
262 
263 static inline struct proc_dir_entry *PDE(const struct inode *inode)
264 {
265 	return PROC_I(inode)->pde;
266 }
267 
268 static inline struct net *PDE_NET(struct proc_dir_entry *pde)
269 {
270 	return pde->parent->data;
271 }
272 
273 struct net *get_proc_net(const struct inode *inode);
274 
275 struct proc_maps_private {
276 	struct pid *pid;
277 	struct task_struct *task;
278 #ifdef CONFIG_MMU
279 	struct vm_area_struct *tail_vma;
280 #endif
281 };
282 
283 #endif /* _LINUX_PROC_FS_H */
284