xref: /linux/fs/proc/internal.h (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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 #include <linux/sched/coredump.h>
18 #include <linux/sched/task.h>
19 
20 struct ctl_table_header;
21 struct mempolicy;
22 
23 /*
24  * This is not completely implemented yet. The idea is to
25  * create an in-memory tree (like the actual /proc filesystem
26  * tree) of these proc_dir_entries, so that we can dynamically
27  * add new files to /proc.
28  *
29  * parent/subdir are used for the directory structure (every /proc file has a
30  * parent, but "subdir" is empty for all non-directory entries).
31  * subdir_node is used to build the rb tree "subdir" of the parent.
32  */
33 struct proc_dir_entry {
34 	unsigned int low_ino;
35 	umode_t mode;
36 	nlink_t nlink;
37 	kuid_t uid;
38 	kgid_t gid;
39 	loff_t size;
40 	const struct inode_operations *proc_iops;
41 	const struct file_operations *proc_fops;
42 	struct proc_dir_entry *parent;
43 	struct rb_root_cached subdir;
44 	struct rb_node subdir_node;
45 	void *data;
46 	atomic_t count;		/* use count */
47 	atomic_t in_use;	/* number of callers into module in progress; */
48 			/* negative -> it's going away RSN */
49 	struct completion *pde_unload_completion;
50 	struct list_head pde_openers;	/* who did ->open, but not ->release */
51 	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
52 	u8 namelen;
53 	char name[];
54 } __randomize_layout;
55 
56 union proc_op {
57 	int (*proc_get_link)(struct dentry *, struct path *);
58 	int (*proc_show)(struct seq_file *m,
59 		struct pid_namespace *ns, struct pid *pid,
60 		struct task_struct *task);
61 };
62 
63 struct proc_inode {
64 	struct pid *pid;
65 	unsigned int fd;
66 	union proc_op op;
67 	struct proc_dir_entry *pde;
68 	struct ctl_table_header *sysctl;
69 	struct ctl_table *sysctl_entry;
70 	struct hlist_node sysctl_inodes;
71 	const struct proc_ns_operations *ns_ops;
72 	struct inode vfs_inode;
73 } __randomize_layout;
74 
75 /*
76  * General functions
77  */
78 static inline struct proc_inode *PROC_I(const struct inode *inode)
79 {
80 	return container_of(inode, struct proc_inode, vfs_inode);
81 }
82 
83 static inline struct proc_dir_entry *PDE(const struct inode *inode)
84 {
85 	return PROC_I(inode)->pde;
86 }
87 
88 static inline void *__PDE_DATA(const struct inode *inode)
89 {
90 	return PDE(inode)->data;
91 }
92 
93 static inline struct pid *proc_pid(struct inode *inode)
94 {
95 	return PROC_I(inode)->pid;
96 }
97 
98 static inline struct task_struct *get_proc_task(struct inode *inode)
99 {
100 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
101 }
102 
103 void task_dump_owner(struct task_struct *task, umode_t mode,
104 		     kuid_t *ruid, kgid_t *rgid);
105 
106 unsigned name_to_int(const struct qstr *qstr);
107 /*
108  * Offset of the first process in the /proc root directory..
109  */
110 #define FIRST_PROCESS_ENTRY 256
111 
112 /* Worst case buffer size needed for holding an integer. */
113 #define PROC_NUMBUF 13
114 
115 /*
116  * array.c
117  */
118 extern const struct file_operations proc_tid_children_operations;
119 
120 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
121 			 struct pid *, struct task_struct *);
122 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
123 			  struct pid *, struct task_struct *);
124 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
125 			   struct pid *, struct task_struct *);
126 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
127 			  struct pid *, struct task_struct *);
128 
129 /*
130  * base.c
131  */
132 extern const struct dentry_operations pid_dentry_operations;
133 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
134 extern int proc_setattr(struct dentry *, struct iattr *);
135 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
136 extern int pid_revalidate(struct dentry *, unsigned int);
137 extern int pid_delete_dentry(const struct dentry *);
138 extern int proc_pid_readdir(struct file *, struct dir_context *);
139 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
140 extern loff_t mem_lseek(struct file *, loff_t, int);
141 
142 /* Lookups */
143 typedef int instantiate_t(struct inode *, struct dentry *,
144 				     struct task_struct *, const void *);
145 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
146 			   instantiate_t, struct task_struct *, const void *);
147 
148 /*
149  * generic.c
150  */
151 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
152 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
153 				     struct dentry *);
154 extern int proc_readdir(struct file *, struct dir_context *);
155 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
156 
157 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
158 {
159 	atomic_inc(&pde->count);
160 	return pde;
161 }
162 extern void pde_put(struct proc_dir_entry *);
163 
164 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
165 {
166 	return S_ISDIR(pde->mode) && !pde->proc_iops;
167 }
168 
169 /*
170  * inode.c
171  */
172 struct pde_opener {
173 	struct file *file;
174 	struct list_head lh;
175 	bool closing;
176 	struct completion *c;
177 };
178 extern const struct inode_operations proc_link_inode_operations;
179 
180 extern const struct inode_operations proc_pid_link_inode_operations;
181 
182 extern void proc_init_inodecache(void);
183 void set_proc_pid_nlink(void);
184 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
185 extern int proc_fill_super(struct super_block *, void *data, int flags);
186 extern void proc_entry_rundown(struct proc_dir_entry *);
187 
188 /*
189  * proc_namespaces.c
190  */
191 extern const struct inode_operations proc_ns_dir_inode_operations;
192 extern const struct file_operations proc_ns_dir_operations;
193 
194 /*
195  * proc_net.c
196  */
197 extern const struct file_operations proc_net_operations;
198 extern const struct inode_operations proc_net_inode_operations;
199 
200 #ifdef CONFIG_NET
201 extern int proc_net_init(void);
202 #else
203 static inline int proc_net_init(void) { return 0; }
204 #endif
205 
206 /*
207  * proc_self.c
208  */
209 extern int proc_setup_self(struct super_block *);
210 
211 /*
212  * proc_thread_self.c
213  */
214 extern int proc_setup_thread_self(struct super_block *);
215 extern void proc_thread_self_init(void);
216 
217 /*
218  * proc_sysctl.c
219  */
220 #ifdef CONFIG_PROC_SYSCTL
221 extern int proc_sys_init(void);
222 extern void proc_sys_evict_inode(struct inode *inode,
223 				 struct ctl_table_header *head);
224 #else
225 static inline void proc_sys_init(void) { }
226 static inline void proc_sys_evict_inode(struct  inode *inode,
227 					struct ctl_table_header *head) { }
228 #endif
229 
230 /*
231  * proc_tty.c
232  */
233 #ifdef CONFIG_TTY
234 extern void proc_tty_init(void);
235 #else
236 static inline void proc_tty_init(void) {}
237 #endif
238 
239 /*
240  * root.c
241  */
242 extern struct proc_dir_entry proc_root;
243 extern int proc_parse_options(char *options, struct pid_namespace *pid);
244 
245 extern void proc_self_init(void);
246 extern int proc_remount(struct super_block *, int *, char *);
247 
248 /*
249  * task_[no]mmu.c
250  */
251 struct mem_size_stats;
252 struct proc_maps_private {
253 	struct inode *inode;
254 	struct task_struct *task;
255 	struct mm_struct *mm;
256 	struct mem_size_stats *rollup;
257 #ifdef CONFIG_MMU
258 	struct vm_area_struct *tail_vma;
259 #endif
260 #ifdef CONFIG_NUMA
261 	struct mempolicy *task_mempolicy;
262 #endif
263 } __randomize_layout;
264 
265 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
266 
267 extern const struct file_operations proc_pid_maps_operations;
268 extern const struct file_operations proc_tid_maps_operations;
269 extern const struct file_operations proc_pid_numa_maps_operations;
270 extern const struct file_operations proc_tid_numa_maps_operations;
271 extern const struct file_operations proc_pid_smaps_operations;
272 extern const struct file_operations proc_pid_smaps_rollup_operations;
273 extern const struct file_operations proc_tid_smaps_operations;
274 extern const struct file_operations proc_clear_refs_operations;
275 extern const struct file_operations proc_pagemap_operations;
276 
277 extern unsigned long task_vsize(struct mm_struct *);
278 extern unsigned long task_statm(struct mm_struct *,
279 				unsigned long *, unsigned long *,
280 				unsigned long *, unsigned long *);
281 extern void task_mem(struct seq_file *, struct mm_struct *);
282