xref: /linux/fs/proc/internal.h (revision 4e1a33b105ddf201f66dcc44490c6086a25eca0b)
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/spinlock.h>
15 #include <linux/atomic.h>
16 #include <linux/binfmts.h>
17 
18 struct ctl_table_header;
19 struct mempolicy;
20 
21 /*
22  * This is not completely implemented yet. The idea is to
23  * create an in-memory tree (like the actual /proc filesystem
24  * tree) of these proc_dir_entries, so that we can dynamically
25  * add new files to /proc.
26  *
27  * parent/subdir are used for the directory structure (every /proc file has a
28  * parent, but "subdir" is empty for all non-directory entries).
29  * subdir_node is used to build the rb tree "subdir" of the parent.
30  */
31 struct proc_dir_entry {
32 	unsigned int low_ino;
33 	umode_t mode;
34 	nlink_t nlink;
35 	kuid_t uid;
36 	kgid_t gid;
37 	loff_t size;
38 	const struct inode_operations *proc_iops;
39 	const struct file_operations *proc_fops;
40 	struct proc_dir_entry *parent;
41 	struct rb_root subdir;
42 	struct rb_node subdir_node;
43 	void *data;
44 	atomic_t count;		/* use count */
45 	atomic_t in_use;	/* number of callers into module in progress; */
46 			/* negative -> it's going away RSN */
47 	struct completion *pde_unload_completion;
48 	struct list_head pde_openers;	/* who did ->open, but not ->release */
49 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
50 	u8 namelen;
51 	char name[];
52 };
53 
54 union proc_op {
55 	int (*proc_get_link)(struct dentry *, struct path *);
56 	int (*proc_show)(struct seq_file *m,
57 		struct pid_namespace *ns, struct pid *pid,
58 		struct task_struct *task);
59 };
60 
61 struct proc_inode {
62 	struct pid *pid;
63 	unsigned int fd;
64 	union proc_op op;
65 	struct proc_dir_entry *pde;
66 	struct ctl_table_header *sysctl;
67 	struct ctl_table *sysctl_entry;
68 	struct list_head sysctl_inodes;
69 	const struct proc_ns_operations *ns_ops;
70 	struct inode vfs_inode;
71 };
72 
73 /*
74  * General functions
75  */
76 static inline struct proc_inode *PROC_I(const struct inode *inode)
77 {
78 	return container_of(inode, struct proc_inode, vfs_inode);
79 }
80 
81 static inline struct proc_dir_entry *PDE(const struct inode *inode)
82 {
83 	return PROC_I(inode)->pde;
84 }
85 
86 static inline void *__PDE_DATA(const struct inode *inode)
87 {
88 	return PDE(inode)->data;
89 }
90 
91 static inline struct pid *proc_pid(struct inode *inode)
92 {
93 	return PROC_I(inode)->pid;
94 }
95 
96 static inline struct task_struct *get_proc_task(struct inode *inode)
97 {
98 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
99 }
100 
101 void task_dump_owner(struct task_struct *task, mode_t mode,
102 		     kuid_t *ruid, kgid_t *rgid);
103 
104 static inline unsigned name_to_int(const struct qstr *qstr)
105 {
106 	const char *name = qstr->name;
107 	int len = qstr->len;
108 	unsigned n = 0;
109 
110 	if (len > 1 && *name == '0')
111 		goto out;
112 	while (len-- > 0) {
113 		unsigned c = *name++ - '0';
114 		if (c > 9)
115 			goto out;
116 		if (n >= (~0U-9)/10)
117 			goto out;
118 		n *= 10;
119 		n += c;
120 	}
121 	return n;
122 out:
123 	return ~0U;
124 }
125 
126 /*
127  * Offset of the first process in the /proc root directory..
128  */
129 #define FIRST_PROCESS_ENTRY 256
130 
131 /* Worst case buffer size needed for holding an integer. */
132 #define PROC_NUMBUF 13
133 
134 /*
135  * array.c
136  */
137 extern const struct file_operations proc_tid_children_operations;
138 
139 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
140 			 struct pid *, struct task_struct *);
141 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
142 			  struct pid *, struct task_struct *);
143 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
144 			   struct pid *, struct task_struct *);
145 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
146 			  struct pid *, struct task_struct *);
147 
148 /*
149  * base.c
150  */
151 extern const struct dentry_operations pid_dentry_operations;
152 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
153 extern int proc_setattr(struct dentry *, struct iattr *);
154 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
155 extern int pid_revalidate(struct dentry *, unsigned int);
156 extern int pid_delete_dentry(const struct dentry *);
157 extern int proc_pid_readdir(struct file *, struct dir_context *);
158 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
159 extern loff_t mem_lseek(struct file *, loff_t, int);
160 
161 /* Lookups */
162 typedef int instantiate_t(struct inode *, struct dentry *,
163 				     struct task_struct *, const void *);
164 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
165 			   instantiate_t, struct task_struct *, const void *);
166 
167 /*
168  * generic.c
169  */
170 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
171 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
172 				     struct dentry *);
173 extern int proc_readdir(struct file *, struct dir_context *);
174 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
175 
176 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
177 {
178 	atomic_inc(&pde->count);
179 	return pde;
180 }
181 extern void pde_put(struct proc_dir_entry *);
182 
183 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
184 {
185 	return S_ISDIR(pde->mode) && !pde->proc_iops;
186 }
187 
188 /*
189  * inode.c
190  */
191 struct pde_opener {
192 	struct file *file;
193 	struct list_head lh;
194 	bool closing;
195 	struct completion *c;
196 };
197 extern const struct inode_operations proc_link_inode_operations;
198 
199 extern const struct inode_operations proc_pid_link_inode_operations;
200 
201 extern void proc_init_inodecache(void);
202 void set_proc_pid_nlink(void);
203 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
204 extern int proc_fill_super(struct super_block *, void *data, int flags);
205 extern void proc_entry_rundown(struct proc_dir_entry *);
206 
207 /*
208  * proc_namespaces.c
209  */
210 extern const struct inode_operations proc_ns_dir_inode_operations;
211 extern const struct file_operations proc_ns_dir_operations;
212 
213 /*
214  * proc_net.c
215  */
216 extern const struct file_operations proc_net_operations;
217 extern const struct inode_operations proc_net_inode_operations;
218 
219 #ifdef CONFIG_NET
220 extern int proc_net_init(void);
221 #else
222 static inline int proc_net_init(void) { return 0; }
223 #endif
224 
225 /*
226  * proc_self.c
227  */
228 extern int proc_setup_self(struct super_block *);
229 
230 /*
231  * proc_thread_self.c
232  */
233 extern int proc_setup_thread_self(struct super_block *);
234 extern void proc_thread_self_init(void);
235 
236 /*
237  * proc_sysctl.c
238  */
239 #ifdef CONFIG_PROC_SYSCTL
240 extern int proc_sys_init(void);
241 extern void proc_sys_evict_inode(struct inode *inode,
242 				 struct ctl_table_header *head);
243 #else
244 static inline void proc_sys_init(void) { }
245 static inline void proc_sys_evict_inode(struct  inode *inode,
246 					struct ctl_table_header *head) { }
247 #endif
248 
249 /*
250  * proc_tty.c
251  */
252 #ifdef CONFIG_TTY
253 extern void proc_tty_init(void);
254 #else
255 static inline void proc_tty_init(void) {}
256 #endif
257 
258 /*
259  * root.c
260  */
261 extern struct proc_dir_entry proc_root;
262 extern int proc_parse_options(char *options, struct pid_namespace *pid);
263 
264 extern void proc_self_init(void);
265 extern int proc_remount(struct super_block *, int *, char *);
266 
267 /*
268  * task_[no]mmu.c
269  */
270 struct proc_maps_private {
271 	struct inode *inode;
272 	struct task_struct *task;
273 	struct mm_struct *mm;
274 #ifdef CONFIG_MMU
275 	struct vm_area_struct *tail_vma;
276 #endif
277 #ifdef CONFIG_NUMA
278 	struct mempolicy *task_mempolicy;
279 #endif
280 };
281 
282 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
283 
284 extern const struct file_operations proc_pid_maps_operations;
285 extern const struct file_operations proc_tid_maps_operations;
286 extern const struct file_operations proc_pid_numa_maps_operations;
287 extern const struct file_operations proc_tid_numa_maps_operations;
288 extern const struct file_operations proc_pid_smaps_operations;
289 extern const struct file_operations proc_tid_smaps_operations;
290 extern const struct file_operations proc_clear_refs_operations;
291 extern const struct file_operations proc_pagemap_operations;
292 
293 extern unsigned long task_vsize(struct mm_struct *);
294 extern unsigned long task_statm(struct mm_struct *,
295 				unsigned long *, unsigned long *,
296 				unsigned long *, unsigned long *);
297 extern void task_mem(struct seq_file *, struct mm_struct *);
298