xref: /linux-6.15/include/linux/proc_fs.h (revision 2a677896)
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 	int pde_users;	/* number of callers into module in progress */
79 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
80 	struct completion *pde_unload_completion;
81 };
82 
83 struct kcore_list {
84 	struct kcore_list *next;
85 	unsigned long addr;
86 	size_t size;
87 };
88 
89 struct vmcore {
90 	struct list_head list;
91 	unsigned long long paddr;
92 	unsigned long long size;
93 	loff_t offset;
94 };
95 
96 #ifdef CONFIG_PROC_FS
97 
98 extern struct proc_dir_entry proc_root;
99 extern struct proc_dir_entry *proc_root_fs;
100 extern struct proc_dir_entry *proc_net;
101 extern struct proc_dir_entry *proc_net_stat;
102 extern struct proc_dir_entry *proc_bus;
103 extern struct proc_dir_entry *proc_root_driver;
104 extern struct proc_dir_entry *proc_root_kcore;
105 
106 extern spinlock_t proc_subdir_lock;
107 
108 extern void proc_root_init(void);
109 extern void proc_misc_init(void);
110 
111 struct mm_struct;
112 
113 void proc_flush_task(struct task_struct *task);
114 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);
115 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir);
116 unsigned long task_vsize(struct mm_struct *);
117 int task_statm(struct mm_struct *, int *, int *, int *, int *);
118 char *task_mem(struct mm_struct *, char *);
119 void clear_refs_smap(struct mm_struct *mm);
120 
121 struct proc_dir_entry *de_get(struct proc_dir_entry *de);
122 void de_put(struct proc_dir_entry *de);
123 
124 extern struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
125 						struct proc_dir_entry *parent);
126 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
127 
128 extern struct vfsmount *proc_mnt;
129 extern int proc_fill_super(struct super_block *,void *,int);
130 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
131 
132 /*
133  * These are generic /proc routines that use the internal
134  * "struct proc_dir_entry" tree to traverse the filesystem.
135  *
136  * The /proc root directory has extended versions to take care
137  * of the /proc/<pid> subdirectories.
138  */
139 extern int proc_readdir(struct file *, void *, filldir_t);
140 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
141 
142 extern const struct file_operations proc_kcore_operations;
143 extern const struct file_operations proc_kmsg_operations;
144 extern const struct file_operations ppc_htab_operations;
145 
146 /*
147  * proc_tty.c
148  */
149 struct tty_driver;
150 extern void proc_tty_init(void);
151 extern void proc_tty_register_driver(struct tty_driver *driver);
152 extern void proc_tty_unregister_driver(struct tty_driver *driver);
153 
154 /*
155  * proc_devtree.c
156  */
157 #ifdef CONFIG_PROC_DEVICETREE
158 struct device_node;
159 struct property;
160 extern void proc_device_tree_init(void);
161 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
162 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
163 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
164 					 struct property *prop);
165 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
166 					 struct property *newprop,
167 					 struct property *oldprop);
168 #endif /* CONFIG_PROC_DEVICETREE */
169 
170 extern struct proc_dir_entry *proc_symlink(const char *,
171 		struct proc_dir_entry *, const char *);
172 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
173 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
174 			struct proc_dir_entry *parent);
175 
176 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
177 	mode_t mode, struct proc_dir_entry *base,
178 	read_proc_t *read_proc, void * data)
179 {
180 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
181 	if (res) {
182 		res->read_proc=read_proc;
183 		res->data=data;
184 	}
185 	return res;
186 }
187 
188 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
189 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
190 {
191 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
192 	if (res) res->get_info=get_info;
193 	return res;
194 }
195 
196 static inline struct proc_dir_entry *proc_net_create(const char *name,
197 	mode_t mode, get_info_t *get_info)
198 {
199 	return create_proc_info_entry(name,mode,proc_net,get_info);
200 }
201 
202 static inline struct proc_dir_entry *proc_net_fops_create(const char *name,
203 	mode_t mode, const struct file_operations *fops)
204 {
205 	struct proc_dir_entry *res = create_proc_entry(name, mode, proc_net);
206 	if (res)
207 		res->proc_fops = fops;
208 	return res;
209 }
210 
211 static inline void proc_net_remove(const char *name)
212 {
213 	remove_proc_entry(name,proc_net);
214 }
215 
216 #else
217 
218 #define proc_root_driver NULL
219 #define proc_net NULL
220 #define proc_bus NULL
221 
222 #define proc_net_fops_create(name, mode, fops)  ({ (void)(mode), NULL; })
223 #define proc_net_create(name, mode, info)	({ (void)(mode), NULL; })
224 static inline void proc_net_remove(const char *name) {}
225 
226 static inline void proc_flush_task(struct task_struct *task) { }
227 
228 static inline struct proc_dir_entry *create_proc_entry(const char *name,
229 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
230 
231 #define remove_proc_entry(name, parent) do {} while (0)
232 
233 static inline struct proc_dir_entry *proc_symlink(const char *name,
234 		struct proc_dir_entry *parent,const char *dest) {return NULL;}
235 static inline struct proc_dir_entry *proc_mkdir(const char *name,
236 	struct proc_dir_entry *parent) {return NULL;}
237 
238 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
239 	mode_t mode, struct proc_dir_entry *base,
240 	read_proc_t *read_proc, void * data) { return NULL; }
241 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
242 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
243 	{ return NULL; }
244 
245 struct tty_driver;
246 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
247 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
248 
249 extern struct proc_dir_entry proc_root;
250 
251 #endif /* CONFIG_PROC_FS */
252 
253 #if !defined(CONFIG_PROC_KCORE)
254 static inline void kclist_add(struct kcore_list *new, void *addr, size_t size)
255 {
256 }
257 #else
258 extern void kclist_add(struct kcore_list *, void *, size_t);
259 #endif
260 
261 union proc_op {
262 	int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
263 	int (*proc_read)(struct task_struct *task, char *page);
264 };
265 
266 struct proc_inode {
267 	struct pid *pid;
268 	int fd;
269 	union proc_op op;
270 	struct proc_dir_entry *pde;
271 	struct inode vfs_inode;
272 };
273 
274 static inline struct proc_inode *PROC_I(const struct inode *inode)
275 {
276 	return container_of(inode, struct proc_inode, vfs_inode);
277 }
278 
279 static inline struct proc_dir_entry *PDE(const struct inode *inode)
280 {
281 	return PROC_I(inode)->pde;
282 }
283 
284 struct proc_maps_private {
285 	struct pid *pid;
286 	struct task_struct *task;
287 #ifdef CONFIG_MMU
288 	struct vm_area_struct *tail_vma;
289 #endif
290 };
291 
292 #endif /* _LINUX_PROC_FS_H */
293