xref: /linux-6.15/include/linux/proc_fs.h (revision 40efcb05)
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 typedef struct proc_dir_entry *(shadow_proc_t)(struct task_struct *task,
52 						struct proc_dir_entry *pde);
53 
54 struct proc_dir_entry {
55 	unsigned int low_ino;
56 	unsigned short namelen;
57 	const char *name;
58 	mode_t mode;
59 	nlink_t nlink;
60 	uid_t uid;
61 	gid_t gid;
62 	loff_t size;
63 	const struct inode_operations *proc_iops;
64 	/*
65 	 * NULL ->proc_fops means "PDE is going away RSN" or
66 	 * "PDE is just created". In either case, e.g. ->read_proc won't be
67 	 * called because it's too late or too early, respectively.
68 	 *
69 	 * If you're allocating ->proc_fops dynamically, save a pointer
70 	 * somewhere.
71 	 */
72 	const struct file_operations *proc_fops;
73 	get_info_t *get_info;
74 	struct module *owner;
75 	struct proc_dir_entry *next, *parent, *subdir;
76 	void *data;
77 	read_proc_t *read_proc;
78 	write_proc_t *write_proc;
79 	atomic_t count;		/* use count */
80 	int pde_users;	/* number of callers into module in progress */
81 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
82 	struct completion *pde_unload_completion;
83 	shadow_proc_t *shadow_proc;
84 };
85 
86 struct kcore_list {
87 	struct kcore_list *next;
88 	unsigned long addr;
89 	size_t size;
90 };
91 
92 struct vmcore {
93 	struct list_head list;
94 	unsigned long long paddr;
95 	unsigned long long size;
96 	loff_t offset;
97 };
98 
99 #ifdef CONFIG_PROC_FS
100 
101 extern struct proc_dir_entry proc_root;
102 extern struct proc_dir_entry *proc_root_fs;
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 struct pid_namespace;
131 extern int proc_fill_super(struct super_block *);
132 extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *);
133 
134 /*
135  * These are generic /proc routines that use the internal
136  * "struct proc_dir_entry" tree to traverse the filesystem.
137  *
138  * The /proc root directory has extended versions to take care
139  * of the /proc/<pid> subdirectories.
140  */
141 extern int proc_readdir(struct file *, void *, filldir_t);
142 extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
143 
144 extern const struct file_operations proc_kcore_operations;
145 extern const struct file_operations proc_kmsg_operations;
146 extern const struct file_operations ppc_htab_operations;
147 
148 extern int pid_ns_prepare_proc(struct pid_namespace *ns);
149 extern void pid_ns_release_proc(struct pid_namespace *ns);
150 
151 /*
152  * proc_tty.c
153  */
154 struct tty_driver;
155 extern void proc_tty_init(void);
156 extern void proc_tty_register_driver(struct tty_driver *driver);
157 extern void proc_tty_unregister_driver(struct tty_driver *driver);
158 
159 /*
160  * proc_devtree.c
161  */
162 #ifdef CONFIG_PROC_DEVICETREE
163 struct device_node;
164 struct property;
165 extern void proc_device_tree_init(void);
166 extern void proc_device_tree_add_node(struct device_node *, struct proc_dir_entry *);
167 extern void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop);
168 extern void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
169 					 struct property *prop);
170 extern void proc_device_tree_update_prop(struct proc_dir_entry *pde,
171 					 struct property *newprop,
172 					 struct property *oldprop);
173 #endif /* CONFIG_PROC_DEVICETREE */
174 
175 extern struct proc_dir_entry *proc_symlink(const char *,
176 		struct proc_dir_entry *, const char *);
177 extern struct proc_dir_entry *proc_mkdir(const char *,struct proc_dir_entry *);
178 extern struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
179 			struct proc_dir_entry *parent);
180 
181 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
182 	mode_t mode, struct proc_dir_entry *base,
183 	read_proc_t *read_proc, void * data)
184 {
185 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
186 	if (res) {
187 		res->read_proc=read_proc;
188 		res->data=data;
189 	}
190 	return res;
191 }
192 
193 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
194 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
195 {
196 	struct proc_dir_entry *res=create_proc_entry(name,mode,base);
197 	if (res) res->get_info=get_info;
198 	return res;
199 }
200 
201 extern struct proc_dir_entry *proc_net_fops_create(struct net *net,
202 	const char *name, mode_t mode, const struct file_operations *fops);
203 extern void proc_net_remove(struct net *net, const char *name);
204 
205 #else
206 
207 #define proc_root_driver NULL
208 #define proc_bus NULL
209 
210 #define proc_net_fops_create(net, name, mode, fops)  ({ (void)(mode), NULL; })
211 static inline void proc_net_remove(struct net *net, const char *name) {}
212 
213 static inline void proc_flush_task(struct task_struct *task)
214 {
215 }
216 
217 static inline struct proc_dir_entry *create_proc_entry(const char *name,
218 	mode_t mode, struct proc_dir_entry *parent) { return NULL; }
219 
220 #define remove_proc_entry(name, parent) do {} while (0)
221 
222 static inline struct proc_dir_entry *proc_symlink(const char *name,
223 		struct proc_dir_entry *parent,const char *dest) {return NULL;}
224 static inline struct proc_dir_entry *proc_mkdir(const char *name,
225 	struct proc_dir_entry *parent) {return NULL;}
226 
227 static inline struct proc_dir_entry *create_proc_read_entry(const char *name,
228 	mode_t mode, struct proc_dir_entry *base,
229 	read_proc_t *read_proc, void * data) { return NULL; }
230 static inline struct proc_dir_entry *create_proc_info_entry(const char *name,
231 	mode_t mode, struct proc_dir_entry *base, get_info_t *get_info)
232 	{ return NULL; }
233 
234 struct tty_driver;
235 static inline void proc_tty_register_driver(struct tty_driver *driver) {};
236 static inline void proc_tty_unregister_driver(struct tty_driver *driver) {};
237 
238 extern struct proc_dir_entry proc_root;
239 
240 static inline int pid_ns_prepare_proc(struct pid_namespace *ns)
241 {
242 	return 0;
243 }
244 
245 static inline void pid_ns_release_proc(struct pid_namespace *ns)
246 {
247 }
248 
249 #endif /* CONFIG_PROC_FS */
250 
251 #if !defined(CONFIG_PROC_KCORE)
252 static inline void kclist_add(struct kcore_list *new, void *addr, size_t size)
253 {
254 }
255 #else
256 extern void kclist_add(struct kcore_list *, void *, size_t);
257 #endif
258 
259 union proc_op {
260 	int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
261 	int (*proc_read)(struct task_struct *task, char *page);
262 };
263 
264 struct proc_inode {
265 	struct pid *pid;
266 	int fd;
267 	union proc_op op;
268 	struct proc_dir_entry *pde;
269 	struct inode vfs_inode;
270 };
271 
272 static inline struct proc_inode *PROC_I(const struct inode *inode)
273 {
274 	return container_of(inode, struct proc_inode, vfs_inode);
275 }
276 
277 static inline struct proc_dir_entry *PDE(const struct inode *inode)
278 {
279 	return PROC_I(inode)->pde;
280 }
281 
282 static inline struct net *PDE_NET(struct proc_dir_entry *pde)
283 {
284 	return pde->parent->data;
285 }
286 
287 struct net *get_proc_net(const struct inode *inode);
288 
289 struct proc_maps_private {
290 	struct pid *pid;
291 	struct task_struct *task;
292 #ifdef CONFIG_MMU
293 	struct vm_area_struct *tail_vma;
294 #endif
295 };
296 
297 #endif /* _LINUX_PROC_FS_H */
298