xref: /linux-6.15/include/linux/proc_fs.h (revision c0a9290e)
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 /* Worst case buffer size needed for holding an integer. */
23 #define PROC_NUMBUF 13
24 
25 /*
26  * We always define these enumerators
27  */
28 
29 enum {
30 	PROC_ROOT_INO = 1,
31 };
32 
33 /*
34  * This is not completely implemented yet. The idea is to
35  * create an in-memory tree (like the actual /proc filesystem
36  * tree) of these proc_dir_entries, so that we can dynamically
37  * add new files to /proc.
38  *
39  * The "next" pointer creates a linked list of one /proc directory,
40  * while parent/subdir create the directory structure (every
41  * /proc file has a parent, but "subdir" is NULL for all
42  * non-directory entries).
43  *
44  * "get_info" is called at "read", while "owner" is used to protect module
45  * from unloading while proc_dir_entry is in use
46  */
47 
48 typedef	int (read_proc_t)(char *page, char **start, off_t off,
49 			  int count, int *eof, void *data);
50 typedef	int (write_proc_t)(struct file *file, const char __user *buffer,
51 			   unsigned long count, void *data);
52 typedef int (get_info_t)(char *, char **, off_t, int);
53 typedef struct proc_dir_entry *(shadow_proc_t)(struct task_struct *task,
54 						struct proc_dir_entry *pde);
55 
56 struct proc_dir_entry {
57 	unsigned int low_ino;
58 	unsigned short namelen;
59 	const char *name;
60 	mode_t mode;
61 	nlink_t nlink;
62 	uid_t uid;
63 	gid_t gid;
64 	loff_t size;
65 	const struct inode_operations *proc_iops;
66 	/*
67 	 * NULL ->proc_fops means "PDE is going away RSN" or
68 	 * "PDE is just created". In either case, e.g. ->read_proc won't be
69 	 * called because it's too late or too early, respectively.
70 	 *
71 	 * If you're allocating ->proc_fops dynamically, save a pointer
72 	 * somewhere.
73 	 */
74 	const struct file_operations *proc_fops;
75 	get_info_t *get_info;
76 	struct module *owner;
77 	struct proc_dir_entry *next, *parent, *subdir;
78 	void *data;
79 	read_proc_t *read_proc;
80 	write_proc_t *write_proc;
81 	atomic_t count;		/* use count */
82 	int pde_users;	/* number of callers into module in progress */
83 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
84 	struct completion *pde_unload_completion;
85 	shadow_proc_t *shadow_proc;
86 };
87 
88 struct kcore_list {
89 	struct kcore_list *next;
90 	unsigned long addr;
91 	size_t size;
92 };
93 
94 struct vmcore {
95 	struct list_head list;
96 	unsigned long long paddr;
97 	unsigned long long size;
98 	loff_t offset;
99 };
100 
101 #ifdef CONFIG_PROC_FS
102 
103 extern struct proc_dir_entry proc_root;
104 extern struct proc_dir_entry *proc_root_fs;
105 extern struct proc_dir_entry *proc_bus;
106 extern struct proc_dir_entry *proc_root_driver;
107 extern struct proc_dir_entry *proc_root_kcore;
108 
109 extern spinlock_t proc_subdir_lock;
110 
111 extern void proc_root_init(void);
112 extern void proc_misc_init(void);
113 
114 struct mm_struct;
115 
116 void proc_flush_task(struct task_struct *task);
117 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);
118 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir);
119 unsigned long task_vsize(struct mm_struct *);
120 int task_statm(struct mm_struct *, int *, int *, int *, int *);
121 char *task_mem(struct mm_struct *, char *);
122 
123 struct proc_dir_entry *de_get(struct proc_dir_entry *de);
124 void de_put(struct proc_dir_entry *de);
125 
126 extern struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
127 						struct proc_dir_entry *parent);
128 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
129 
130 extern struct vfsmount *proc_mnt;
131 struct pid_namespace;
132 extern int proc_fill_super(struct super_block *);
133 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
134 
135 /*
136  * These are generic /proc routines that use the internal
137  * "struct proc_dir_entry" tree to traverse the filesystem.
138  *
139  * The /proc root directory has extended versions to take care
140  * of the /proc/<pid> subdirectories.
141  */
142 extern int proc_readdir(struct file *, void *, filldir_t);
143 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
144 
145 extern const struct file_operations proc_kcore_operations;
146 extern const struct file_operations proc_kmsg_operations;
147 extern const struct file_operations ppc_htab_operations;
148 
149 extern int pid_ns_prepare_proc(struct pid_namespace *ns);
150 extern void pid_ns_release_proc(struct pid_namespace *ns);
151 
152 /*
153  * proc_tty.c
154  */
155 struct tty_driver;
156 extern void proc_tty_init(void);
157 extern void proc_tty_register_driver(struct tty_driver *driver);
158 extern void proc_tty_unregister_driver(struct tty_driver *driver);
159 
160 /*
161  * proc_devtree.c
162  */
163 #ifdef CONFIG_PROC_DEVICETREE
164 struct device_node;
165 struct property;
166 extern void proc_device_tree_init(void);
167 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
168 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
169 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
170 					 struct property *prop);
171 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
172 					 struct property *newprop,
173 					 struct property *oldprop);
174 #endif /* CONFIG_PROC_DEVICETREE */
175 
176 extern struct proc_dir_entry *proc_symlink(const char *,
177 		struct proc_dir_entry *, const char *);
178 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
179 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
180 			struct proc_dir_entry *parent);
181 
182 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
183 	mode_t mode, struct proc_dir_entry *base,
184 	read_proc_t *read_proc, void * data)
185 {
186 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
187 	if (res) {
188 		res->read_proc=read_proc;
189 		res->data=data;
190 	}
191 	return res;
192 }
193 
194 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
195 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
196 {
197 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
198 	if (res) res->get_info=get_info;
199 	return res;
200 }
201 
202 extern struct proc_dir_entry *proc_net_fops_create(struct net *net,
203 	const char *name, mode_t mode, const struct file_operations *fops);
204 extern void proc_net_remove(struct net *net, const char *name);
205 extern struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
206 	struct proc_dir_entry *parent);
207 
208 #else
209 
210 #define proc_root_driver NULL
211 #define proc_bus NULL
212 
213 #define proc_net_fops_create(net, name, mode, fops)  ({ (void)(mode), NULL; })
214 static inline void proc_net_remove(struct net *net, const char *name) {}
215 
216 static inline void proc_flush_task(struct task_struct *task)
217 {
218 }
219 
220 static inline struct proc_dir_entry *create_proc_entry(const char *name,
221 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
222 
223 #define remove_proc_entry(name, parent) do {} while (0)
224 
225 static inline struct proc_dir_entry *proc_symlink(const char *name,
226 		struct proc_dir_entry *parent,const char *dest) {return NULL;}
227 static inline struct proc_dir_entry *proc_mkdir(const char *name,
228 	struct proc_dir_entry *parent) {return NULL;}
229 
230 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
231 	mode_t mode, struct proc_dir_entry *base,
232 	read_proc_t *read_proc, void * data) { return NULL; }
233 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
234 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
235 	{ return NULL; }
236 
237 struct tty_driver;
238 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
239 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
240 
241 extern struct proc_dir_entry proc_root;
242 
243 static inline int pid_ns_prepare_proc(struct pid_namespace *ns)
244 {
245 	return 0;
246 }
247 
248 static inline void pid_ns_release_proc(struct pid_namespace *ns)
249 {
250 }
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 static inline struct net *PDE_NET(struct proc_dir_entry *pde)
286 {
287 	return pde->parent->data;
288 }
289 
290 struct net *get_proc_net(const struct inode *inode);
291 
292 struct proc_maps_private {
293 	struct pid *pid;
294 	struct task_struct *task;
295 #ifdef CONFIG_MMU
296 	struct vm_area_struct *tail_vma;
297 #endif
298 };
299 
300 #endif /* _LINUX_PROC_FS_H */
301