xref: /linux-6.15/include/linux/proc_fs.h (revision 5134d8fe)
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 void task_mem(struct seq_file *, struct mm_struct *);
122 void clear_refs_smap(struct mm_struct *mm);
123 
124 struct proc_dir_entry *de_get(struct proc_dir_entry *de);
125 void de_put(struct proc_dir_entry *de);
126 
127 extern struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
128 						struct proc_dir_entry *parent);
129 struct proc_dir_entry *proc_create(const char *name, mode_t mode,
130 				struct proc_dir_entry *parent,
131 				const struct file_operations *proc_fops);
132 extern void remove_proc_entry(const char *name, struct proc_dir_entry *parent);
133 
134 extern struct vfsmount *proc_mnt;
135 struct pid_namespace;
136 extern int proc_fill_super(struct super_block *);
137 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
138 
139 /*
140  * These are generic /proc routines that use the internal
141  * "struct proc_dir_entry" tree to traverse the filesystem.
142  *
143  * The /proc root directory has extended versions to take care
144  * of the /proc/<pid> subdirectories.
145  */
146 extern int proc_readdir(struct file *, void *, filldir_t);
147 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
148 
149 extern const struct file_operations proc_kcore_operations;
150 extern const struct file_operations proc_kmsg_operations;
151 extern const struct file_operations ppc_htab_operations;
152 
153 extern int pid_ns_prepare_proc(struct pid_namespace *ns);
154 extern void pid_ns_release_proc(struct pid_namespace *ns);
155 
156 /*
157  * proc_tty.c
158  */
159 struct tty_driver;
160 extern void proc_tty_init(void);
161 extern void proc_tty_register_driver(struct tty_driver *driver);
162 extern void proc_tty_unregister_driver(struct tty_driver *driver);
163 
164 /*
165  * proc_devtree.c
166  */
167 #ifdef CONFIG_PROC_DEVICETREE
168 struct device_node;
169 struct property;
170 extern void proc_device_tree_init(void);
171 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
172 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
173 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
174 					 struct property *prop);
175 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
176 					 struct property *newprop,
177 					 struct property *oldprop);
178 #endif /* CONFIG_PROC_DEVICETREE */
179 
180 extern struct proc_dir_entry *proc_symlink(const char *,
181 		struct proc_dir_entry *, const char *);
182 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
183 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
184 			struct proc_dir_entry *parent);
185 
186 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
187 	mode_t mode, struct proc_dir_entry *base,
188 	read_proc_t *read_proc, void * data)
189 {
190 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
191 	if (res) {
192 		res->read_proc=read_proc;
193 		res->data=data;
194 	}
195 	return res;
196 }
197 
198 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
199 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
200 {
201 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
202 	if (res) res->get_info=get_info;
203 	return res;
204 }
205 
206 extern struct proc_dir_entry *proc_net_fops_create(struct net *net,
207 	const char *name, mode_t mode, const struct file_operations *fops);
208 extern void proc_net_remove(struct net *net, const char *name);
209 extern struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
210 	struct proc_dir_entry *parent);
211 
212 #else
213 
214 #define proc_root_driver NULL
215 #define proc_bus NULL
216 
217 #define proc_net_fops_create(net, name, mode, fops)  ({ (void)(mode), NULL; })
218 static inline void proc_net_remove(struct net *net, const char *name) {}
219 
220 static inline void proc_flush_task(struct task_struct *task)
221 {
222 }
223 
224 static inline struct proc_dir_entry *create_proc_entry(const char *name,
225 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
226 static inline struct proc_dir_entry *proc_create(const char *name,
227 	mode_t mode, struct proc_dir_entry *parent,
228 	const struct file_operations *proc_fops)
229 {
230 	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 static inline int pid_ns_prepare_proc(struct pid_namespace *ns)
253 {
254 	return 0;
255 }
256 
257 static inline void pid_ns_release_proc(struct pid_namespace *ns)
258 {
259 }
260 
261 #endif /* CONFIG_PROC_FS */
262 
263 #if !defined(CONFIG_PROC_KCORE)
264 static inline void kclist_add(struct kcore_list *new, void *addr, size_t size)
265 {
266 }
267 #else
268 extern void kclist_add(struct kcore_list *, void *, size_t);
269 #endif
270 
271 union proc_op {
272 	int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
273 	int (*proc_read)(struct task_struct *task, char *page);
274 	int (*proc_show)(struct seq_file *m,
275 		struct pid_namespace *ns, struct pid *pid,
276 		struct task_struct *task);
277 };
278 
279 struct proc_inode {
280 	struct pid *pid;
281 	int fd;
282 	union proc_op op;
283 	struct proc_dir_entry *pde;
284 	struct inode vfs_inode;
285 };
286 
287 static inline struct proc_inode *PROC_I(const struct inode *inode)
288 {
289 	return container_of(inode, struct proc_inode, vfs_inode);
290 }
291 
292 static inline struct proc_dir_entry *PDE(const struct inode *inode)
293 {
294 	return PROC_I(inode)->pde;
295 }
296 
297 static inline struct net *PDE_NET(struct proc_dir_entry *pde)
298 {
299 	return pde->parent->data;
300 }
301 
302 struct net *get_proc_net(const struct inode *inode);
303 
304 struct proc_maps_private {
305 	struct pid *pid;
306 	struct task_struct *task;
307 #ifdef CONFIG_MMU
308 	struct vm_area_struct *tail_vma;
309 #endif
310 };
311 
312 #endif /* _LINUX_PROC_FS_H */
313