xref: /linux/fs/proc/internal.h (revision 930352862e9533fecc42c7ed20798a7c9e3aa874)
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  * The "next" pointer creates a linked list of one /proc directory,
28  * while parent/subdir create the directory structure (every
29  * /proc file has a parent, but "subdir" is NULL for all
30  * non-directory entries).
31  */
32 struct proc_dir_entry {
33 	unsigned int low_ino;
34 	umode_t mode;
35 	nlink_t nlink;
36 	kuid_t uid;
37 	kgid_t gid;
38 	loff_t size;
39 	const struct inode_operations *proc_iops;
40 	const struct file_operations *proc_fops;
41 	struct proc_dir_entry *next, *parent, *subdir;
42 	void *data;
43 	atomic_t count;		/* use count */
44 	atomic_t in_use;	/* number of callers into module in progress; */
45 			/* negative -> it's going away RSN */
46 	struct completion *pde_unload_completion;
47 	struct list_head pde_openers;	/* who did ->open, but not ->release */
48 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
49 	u8 namelen;
50 	char name[];
51 };
52 
53 union proc_op {
54 	int (*proc_get_link)(struct dentry *, struct path *);
55 	int (*proc_show)(struct seq_file *m,
56 		struct pid_namespace *ns, struct pid *pid,
57 		struct task_struct *task);
58 };
59 
60 struct proc_inode {
61 	struct pid *pid;
62 	int fd;
63 	union proc_op op;
64 	struct proc_dir_entry *pde;
65 	struct ctl_table_header *sysctl;
66 	struct ctl_table *sysctl_entry;
67 	struct proc_ns ns;
68 	struct inode vfs_inode;
69 };
70 
71 /*
72  * General functions
73  */
74 static inline struct proc_inode *PROC_I(const struct inode *inode)
75 {
76 	return container_of(inode, struct proc_inode, vfs_inode);
77 }
78 
79 static inline struct proc_dir_entry *PDE(const struct inode *inode)
80 {
81 	return PROC_I(inode)->pde;
82 }
83 
84 static inline void *__PDE_DATA(const struct inode *inode)
85 {
86 	return PDE(inode)->data;
87 }
88 
89 static inline struct pid *proc_pid(struct inode *inode)
90 {
91 	return PROC_I(inode)->pid;
92 }
93 
94 static inline struct task_struct *get_proc_task(struct inode *inode)
95 {
96 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
97 }
98 
99 static inline int task_dumpable(struct task_struct *task)
100 {
101 	int dumpable = 0;
102 	struct mm_struct *mm;
103 
104 	task_lock(task);
105 	mm = task->mm;
106 	if (mm)
107 		dumpable = get_dumpable(mm);
108 	task_unlock(task);
109 	if (dumpable == SUID_DUMP_USER)
110 		return 1;
111 	return 0;
112 }
113 
114 static inline unsigned name_to_int(const struct qstr *qstr)
115 {
116 	const char *name = qstr->name;
117 	int len = qstr->len;
118 	unsigned n = 0;
119 
120 	if (len > 1 && *name == '0')
121 		goto out;
122 	while (len-- > 0) {
123 		unsigned c = *name++ - '0';
124 		if (c > 9)
125 			goto out;
126 		if (n >= (~0U-9)/10)
127 			goto out;
128 		n *= 10;
129 		n += c;
130 	}
131 	return n;
132 out:
133 	return ~0U;
134 }
135 
136 /*
137  * Offset of the first process in the /proc root directory..
138  */
139 #define FIRST_PROCESS_ENTRY 256
140 
141 /* Worst case buffer size needed for holding an integer. */
142 #define PROC_NUMBUF 13
143 
144 /*
145  * array.c
146  */
147 extern const struct file_operations proc_tid_children_operations;
148 
149 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
150 			 struct pid *, struct task_struct *);
151 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
152 			  struct pid *, struct task_struct *);
153 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
154 			   struct pid *, struct task_struct *);
155 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
156 			  struct pid *, struct task_struct *);
157 
158 /*
159  * base.c
160  */
161 extern const struct dentry_operations pid_dentry_operations;
162 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
163 extern int proc_setattr(struct dentry *, struct iattr *);
164 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *);
165 extern int pid_revalidate(struct dentry *, unsigned int);
166 extern int pid_delete_dentry(const struct dentry *);
167 extern int proc_pid_readdir(struct file *, struct dir_context *);
168 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
169 extern loff_t mem_lseek(struct file *, loff_t, int);
170 
171 /* Lookups */
172 typedef int instantiate_t(struct inode *, struct dentry *,
173 				     struct task_struct *, const void *);
174 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
175 			   instantiate_t, struct task_struct *, const void *);
176 
177 /*
178  * generic.c
179  */
180 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
181 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
182 				     struct dentry *);
183 extern int proc_readdir(struct file *, struct dir_context *);
184 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
185 
186 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
187 {
188 	atomic_inc(&pde->count);
189 	return pde;
190 }
191 extern void pde_put(struct proc_dir_entry *);
192 
193 /*
194  * inode.c
195  */
196 struct pde_opener {
197 	struct file *file;
198 	struct list_head lh;
199 	int closing;
200 	struct completion *c;
201 };
202 
203 extern const struct inode_operations proc_pid_link_inode_operations;
204 
205 extern void proc_init_inodecache(void);
206 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
207 extern int proc_fill_super(struct super_block *);
208 extern void proc_entry_rundown(struct proc_dir_entry *);
209 
210 /*
211  * proc_namespaces.c
212  */
213 extern const struct inode_operations proc_ns_dir_inode_operations;
214 extern const struct file_operations proc_ns_dir_operations;
215 
216 /*
217  * proc_net.c
218  */
219 extern const struct file_operations proc_net_operations;
220 extern const struct inode_operations proc_net_inode_operations;
221 
222 #ifdef CONFIG_NET
223 extern int proc_net_init(void);
224 #else
225 static inline int proc_net_init(void) { return 0; }
226 #endif
227 
228 /*
229  * proc_self.c
230  */
231 extern int proc_setup_self(struct super_block *);
232 
233 /*
234  * proc_thread_self.c
235  */
236 extern int proc_setup_thread_self(struct super_block *);
237 extern void proc_thread_self_init(void);
238 
239 /*
240  * proc_sysctl.c
241  */
242 #ifdef CONFIG_PROC_SYSCTL
243 extern int proc_sys_init(void);
244 extern void sysctl_head_put(struct ctl_table_header *);
245 #else
246 static inline void proc_sys_init(void) { }
247 static inline void sysctl_head_put(struct ctl_table_header *head) { }
248 #endif
249 
250 /*
251  * proc_tty.c
252  */
253 #ifdef CONFIG_TTY
254 extern void proc_tty_init(void);
255 #else
256 static inline void proc_tty_init(void) {}
257 #endif
258 
259 /*
260  * root.c
261  */
262 extern struct proc_dir_entry proc_root;
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