xref: /linux-6.15/include/linux/proc_fs.h (revision aeb3f462)
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 completion;
11 
12 /*
13  * The proc filesystem constants/structures
14  */
15 
16 /*
17  * Offset of the first process in the /proc root directory..
18  */
19 #define FIRST_PROCESS_ENTRY 256
20 
21 
22 /*
23  * We always define these enumerators
24  */
25 
26 enum {
27 	PROC_ROOT_INO = 1,
28 };
29 
30 /*
31  * This is not completely implemented yet. The idea is to
32  * create an in-memory tree (like the actual /proc filesystem
33  * tree) of these proc_dir_entries, so that we can dynamically
34  * add new files to /proc.
35  *
36  * The "next" pointer creates a linked list of one /proc directory,
37  * while parent/subdir create the directory structure (every
38  * /proc file has a parent, but "subdir" is NULL for all
39  * non-directory entries).
40  *
41  * "get_info" is called at "read", while "owner" is used to protect module
42  * from unloading while proc_dir_entry is in use
43  */
44 
45 typedef	int (read_proc_t)(char *page, char **start, off_t off,
46 			  int count, int *eof, void *data);
47 typedef	int (write_proc_t)(struct file *file, const char __user *buffer,
48 			   unsigned long count, void *data);
49 typedef int (get_info_t)(char *, char **, off_t, int);
50 
51 struct proc_dir_entry {
52 	unsigned int low_ino;
53 	unsigned short namelen;
54 	const char *name;
55 	mode_t mode;
56 	nlink_t nlink;
57 	uid_t uid;
58 	gid_t gid;
59 	loff_t size;
60 	const struct inode_operations *proc_iops;
61 	/*
62 	 * NULL ->proc_fops means "PDE is going away RSN" or
63 	 * "PDE is just created". In either case, e.g. ->read_proc won't be
64 	 * called because it's too late or too early, respectively.
65 	 *
66 	 * If you're allocating ->proc_fops dynamically, save a pointer
67 	 * somewhere.
68 	 */
69 	const struct file_operations *proc_fops;
70 	get_info_t *get_info;
71 	struct module *owner;
72 	struct proc_dir_entry *next, *parent, *subdir;
73 	void *data;
74 	read_proc_t *read_proc;
75 	write_proc_t *write_proc;
76 	atomic_t count;		/* use count */
77 	int deleted;		/* delete flag */
78 	void *set;
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_net;
102 extern struct proc_dir_entry *proc_net_stat;
103 extern struct proc_dir_entry *proc_bus;
104 extern struct proc_dir_entry *proc_root_driver;
105 extern struct proc_dir_entry *proc_root_kcore;
106 
107 extern spinlock_t proc_subdir_lock;
108 
109 extern void proc_root_init(void);
110 extern void proc_misc_init(void);
111 
112 struct mm_struct;
113 
114 void proc_flush_task(struct task_struct *task);
115 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);
116 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir);
117 unsigned long task_vsize(struct mm_struct *);
118 int task_statm(struct mm_struct *, int *, int *, int *, int *);
119 char *task_mem(struct mm_struct *, char *);
120 void clear_refs_smap(struct mm_struct *mm);
121 
122 struct proc_dir_entry *de_get(struct proc_dir_entry *de);
123 void de_put(struct proc_dir_entry *de);
124 
125 extern struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
126 						struct proc_dir_entry *parent);
127 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
128 
129 extern struct vfsmount *proc_mnt;
130 extern int proc_fill_super(struct super_block *,void *,int);
131 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
132 
133 /*
134  * These are generic /proc routines that use the internal
135  * "struct proc_dir_entry" tree to traverse the filesystem.
136  *
137  * The /proc root directory has extended versions to take care
138  * of the /proc/<pid> subdirectories.
139  */
140 extern int proc_readdir(struct file *, void *, filldir_t);
141 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
142 
143 extern const struct file_operations proc_kcore_operations;
144 extern const struct file_operations proc_kmsg_operations;
145 extern const struct file_operations ppc_htab_operations;
146 
147 /*
148  * proc_tty.c
149  */
150 struct tty_driver;
151 extern void proc_tty_init(void);
152 extern void proc_tty_register_driver(struct tty_driver *driver);
153 extern void proc_tty_unregister_driver(struct tty_driver *driver);
154 
155 /*
156  * proc_devtree.c
157  */
158 #ifdef CONFIG_PROC_DEVICETREE
159 struct device_node;
160 struct property;
161 extern void proc_device_tree_init(void);
162 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
163 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
164 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
165 					 struct property *prop);
166 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
167 					 struct property *newprop,
168 					 struct property *oldprop);
169 #endif /* CONFIG_PROC_DEVICETREE */
170 
171 extern struct proc_dir_entry *proc_symlink(const char *,
172 		struct proc_dir_entry *, const char *);
173 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
174 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
175 			struct proc_dir_entry *parent);
176 
177 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
178 	mode_t mode, struct proc_dir_entry *base,
179 	read_proc_t *read_proc, void * data)
180 {
181 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
182 	if (res) {
183 		res->read_proc=read_proc;
184 		res->data=data;
185 	}
186 	return res;
187 }
188 
189 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
190 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
191 {
192 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
193 	if (res) res->get_info=get_info;
194 	return res;
195 }
196 
197 static inline struct proc_dir_entry *proc_net_create(const char *name,
198 	mode_t mode, get_info_t *get_info)
199 {
200 	return create_proc_info_entry(name,mode,proc_net,get_info);
201 }
202 
203 static inline struct proc_dir_entry *proc_net_fops_create(const char *name,
204 	mode_t mode, const struct file_operations *fops)
205 {
206 	struct proc_dir_entry *res = create_proc_entry(name, mode, proc_net);
207 	if (res)
208 		res->proc_fops = fops;
209 	return res;
210 }
211 
212 static inline void proc_net_remove(const char *name)
213 {
214 	remove_proc_entry(name,proc_net);
215 }
216 
217 #else
218 
219 #define proc_root_driver NULL
220 #define proc_net NULL
221 #define proc_bus NULL
222 
223 #define proc_net_fops_create(name, mode, fops)  ({ (void)(mode), NULL; })
224 #define proc_net_create(name, mode, info)	({ (void)(mode), NULL; })
225 static inline void proc_net_remove(const char *name) {}
226 
227 static inline void proc_flush_task(struct task_struct *task) { }
228 
229 static inline struct proc_dir_entry *create_proc_entry(const char *name,
230 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
231 
232 #define remove_proc_entry(name, parent) do {} while (0)
233 
234 static inline struct proc_dir_entry *proc_symlink(const char *name,
235 		struct proc_dir_entry *parent,const char *dest) {return NULL;}
236 static inline struct proc_dir_entry *proc_mkdir(const char *name,
237 	struct proc_dir_entry *parent) {return NULL;}
238 
239 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
240 	mode_t mode, struct proc_dir_entry *base,
241 	read_proc_t *read_proc, void * data) { return NULL; }
242 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
243 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
244 	{ return NULL; }
245 
246 struct tty_driver;
247 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
248 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
249 
250 extern struct proc_dir_entry proc_root;
251 
252 #endif /* CONFIG_PROC_FS */
253 
254 #if !defined(CONFIG_PROC_KCORE)
255 static inline void kclist_add(struct kcore_list *new, void *addr, size_t size)
256 {
257 }
258 #else
259 extern void kclist_add(struct kcore_list *, void *, size_t);
260 #endif
261 
262 union proc_op {
263 	int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
264 	int (*proc_read)(struct task_struct *task, char *page);
265 };
266 
267 struct proc_inode {
268 	struct pid *pid;
269 	int fd;
270 	union proc_op op;
271 	struct proc_dir_entry *pde;
272 	struct inode vfs_inode;
273 };
274 
275 static inline struct proc_inode *PROC_I(const struct inode *inode)
276 {
277 	return container_of(inode, struct proc_inode, vfs_inode);
278 }
279 
280 static inline struct proc_dir_entry *PDE(const struct inode *inode)
281 {
282 	return PROC_I(inode)->pde;
283 }
284 
285 struct proc_maps_private {
286 	struct pid *pid;
287 	struct task_struct *task;
288 #ifdef CONFIG_MMU
289 	struct vm_area_struct *tail_vma;
290 #endif
291 };
292 
293 #endif /* _LINUX_PROC_FS_H */
294