xref: /linux/fs/proc/internal.h (revision 564def71765caf65040f926c0783b9c27cc6c087)
1 /* Internal procfs definitions
2  *
3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/proc_fs.h>
13 #include <linux/proc_ns.h>
14 #include <linux/refcount.h>
15 #include <linux/spinlock.h>
16 #include <linux/atomic.h>
17 #include <linux/binfmts.h>
18 #include <linux/sched/coredump.h>
19 #include <linux/sched/task.h>
20 
21 struct ctl_table_header;
22 struct mempolicy;
23 
24 /*
25  * This is not completely implemented yet. The idea is to
26  * create an in-memory tree (like the actual /proc filesystem
27  * tree) of these proc_dir_entries, so that we can dynamically
28  * add new files to /proc.
29  *
30  * parent/subdir are used for the directory structure (every /proc file has a
31  * parent, but "subdir" is empty for all non-directory entries).
32  * subdir_node is used to build the rb tree "subdir" of the parent.
33  */
34 struct proc_dir_entry {
35 	/*
36 	 * number of callers into module in progress;
37 	 * negative -> it's going away RSN
38 	 */
39 	atomic_t in_use;
40 	refcount_t refcnt;
41 	struct list_head pde_openers;	/* who did ->open, but not ->release */
42 	/* protects ->pde_openers and all struct pde_opener instances */
43 	spinlock_t pde_unload_lock;
44 	struct completion *pde_unload_completion;
45 	const struct inode_operations *proc_iops;
46 	const struct file_operations *proc_fops;
47 	union {
48 		const struct seq_operations *seq_ops;
49 		int (*single_show)(struct seq_file *, void *);
50 	};
51 	proc_write_t write;
52 	void *data;
53 	unsigned int state_size;
54 	unsigned int low_ino;
55 	nlink_t nlink;
56 	kuid_t uid;
57 	kgid_t gid;
58 	loff_t size;
59 	struct proc_dir_entry *parent;
60 	struct rb_root subdir;
61 	struct rb_node subdir_node;
62 	char *name;
63 	umode_t mode;
64 	u8 namelen;
65 #ifdef CONFIG_64BIT
66 #define SIZEOF_PDE_INLINE_NAME	(192-155)
67 #else
68 #define SIZEOF_PDE_INLINE_NAME	(128-95)
69 #endif
70 	char inline_name[SIZEOF_PDE_INLINE_NAME];
71 } __randomize_layout;
72 
73 extern struct kmem_cache *proc_dir_entry_cache;
74 void pde_free(struct proc_dir_entry *pde);
75 
76 union proc_op {
77 	int (*proc_get_link)(struct dentry *, struct path *);
78 	int (*proc_show)(struct seq_file *m,
79 		struct pid_namespace *ns, struct pid *pid,
80 		struct task_struct *task);
81 };
82 
83 struct proc_inode {
84 	struct pid *pid;
85 	unsigned int fd;
86 	union proc_op op;
87 	struct proc_dir_entry *pde;
88 	struct ctl_table_header *sysctl;
89 	struct ctl_table *sysctl_entry;
90 	struct hlist_node sysctl_inodes;
91 	const struct proc_ns_operations *ns_ops;
92 	struct inode vfs_inode;
93 } __randomize_layout;
94 
95 /*
96  * General functions
97  */
98 static inline struct proc_inode *PROC_I(const struct inode *inode)
99 {
100 	return container_of(inode, struct proc_inode, vfs_inode);
101 }
102 
103 static inline struct proc_dir_entry *PDE(const struct inode *inode)
104 {
105 	return PROC_I(inode)->pde;
106 }
107 
108 static inline void *__PDE_DATA(const struct inode *inode)
109 {
110 	return PDE(inode)->data;
111 }
112 
113 static inline struct pid *proc_pid(struct inode *inode)
114 {
115 	return PROC_I(inode)->pid;
116 }
117 
118 static inline struct task_struct *get_proc_task(struct inode *inode)
119 {
120 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
121 }
122 
123 void task_dump_owner(struct task_struct *task, umode_t mode,
124 		     kuid_t *ruid, kgid_t *rgid);
125 
126 unsigned name_to_int(const struct qstr *qstr);
127 /*
128  * Offset of the first process in the /proc root directory..
129  */
130 #define FIRST_PROCESS_ENTRY 256
131 
132 /* Worst case buffer size needed for holding an integer. */
133 #define PROC_NUMBUF 13
134 
135 /*
136  * array.c
137  */
138 extern const struct file_operations proc_tid_children_operations;
139 
140 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
141 			 struct pid *, struct task_struct *);
142 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
143 			  struct pid *, struct task_struct *);
144 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
145 			   struct pid *, struct task_struct *);
146 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
147 			  struct pid *, struct task_struct *);
148 
149 /*
150  * base.c
151  */
152 extern const struct dentry_operations pid_dentry_operations;
153 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
154 extern int proc_setattr(struct dentry *, struct iattr *);
155 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
156 extern int pid_revalidate(struct dentry *, unsigned int);
157 extern int pid_delete_dentry(const struct dentry *);
158 extern int proc_pid_readdir(struct file *, struct dir_context *);
159 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
160 extern loff_t mem_lseek(struct file *, loff_t, int);
161 
162 /* Lookups */
163 typedef int instantiate_t(struct inode *, struct dentry *,
164 				     struct task_struct *, const void *);
165 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
166 			   instantiate_t, struct task_struct *, const void *);
167 
168 /*
169  * generic.c
170  */
171 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
172 		struct proc_dir_entry **parent, void *data);
173 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
174 		struct proc_dir_entry *dp);
175 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
176 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
177 extern int proc_readdir(struct file *, struct dir_context *);
178 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
179 
180 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
181 {
182 	refcount_inc(&pde->refcnt);
183 	return pde;
184 }
185 extern void pde_put(struct proc_dir_entry *);
186 
187 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
188 {
189 	return S_ISDIR(pde->mode) && !pde->proc_iops;
190 }
191 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *);
192 
193 /*
194  * inode.c
195  */
196 struct pde_opener {
197 	struct file *file;
198 	struct list_head lh;
199 	bool closing;
200 	struct completion *c;
201 } __randomize_layout;
202 extern const struct inode_operations proc_link_inode_operations;
203 
204 extern const struct inode_operations proc_pid_link_inode_operations;
205 
206 void proc_init_kmemcache(void);
207 void set_proc_pid_nlink(void);
208 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
209 extern int proc_fill_super(struct super_block *, void *data, int flags);
210 extern void proc_entry_rundown(struct proc_dir_entry *);
211 
212 /*
213  * proc_namespaces.c
214  */
215 extern const struct inode_operations proc_ns_dir_inode_operations;
216 extern const struct file_operations proc_ns_dir_operations;
217 
218 /*
219  * proc_net.c
220  */
221 extern const struct file_operations proc_net_operations;
222 extern const struct inode_operations proc_net_inode_operations;
223 
224 #ifdef CONFIG_NET
225 extern int proc_net_init(void);
226 #else
227 static inline int proc_net_init(void) { return 0; }
228 #endif
229 
230 /*
231  * proc_self.c
232  */
233 extern int proc_setup_self(struct super_block *);
234 
235 /*
236  * proc_thread_self.c
237  */
238 extern int proc_setup_thread_self(struct super_block *);
239 extern void proc_thread_self_init(void);
240 
241 /*
242  * proc_sysctl.c
243  */
244 #ifdef CONFIG_PROC_SYSCTL
245 extern int proc_sys_init(void);
246 extern void proc_sys_evict_inode(struct inode *inode,
247 				 struct ctl_table_header *head);
248 #else
249 static inline void proc_sys_init(void) { }
250 static inline void proc_sys_evict_inode(struct  inode *inode,
251 					struct ctl_table_header *head) { }
252 #endif
253 
254 /*
255  * proc_tty.c
256  */
257 #ifdef CONFIG_TTY
258 extern void proc_tty_init(void);
259 #else
260 static inline void proc_tty_init(void) {}
261 #endif
262 
263 /*
264  * root.c
265  */
266 extern struct proc_dir_entry proc_root;
267 extern int proc_parse_options(char *options, struct pid_namespace *pid);
268 
269 extern void proc_self_init(void);
270 extern int proc_remount(struct super_block *, int *, char *);
271 
272 /*
273  * task_[no]mmu.c
274  */
275 struct mem_size_stats;
276 struct proc_maps_private {
277 	struct inode *inode;
278 	struct task_struct *task;
279 	struct mm_struct *mm;
280 	struct mem_size_stats *rollup;
281 #ifdef CONFIG_MMU
282 	struct vm_area_struct *tail_vma;
283 #endif
284 #ifdef CONFIG_NUMA
285 	struct mempolicy *task_mempolicy;
286 #endif
287 } __randomize_layout;
288 
289 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
290 
291 extern const struct file_operations proc_pid_maps_operations;
292 extern const struct file_operations proc_tid_maps_operations;
293 extern const struct file_operations proc_pid_numa_maps_operations;
294 extern const struct file_operations proc_tid_numa_maps_operations;
295 extern const struct file_operations proc_pid_smaps_operations;
296 extern const struct file_operations proc_pid_smaps_rollup_operations;
297 extern const struct file_operations proc_tid_smaps_operations;
298 extern const struct file_operations proc_clear_refs_operations;
299 extern const struct file_operations proc_pagemap_operations;
300 
301 extern unsigned long task_vsize(struct mm_struct *);
302 extern unsigned long task_statm(struct mm_struct *,
303 				unsigned long *, unsigned long *,
304 				unsigned long *, unsigned long *);
305 extern void task_mem(struct seq_file *, struct mm_struct *);
306