xref: /linux/fs/proc/internal.h (revision 6b16f5d12202a23d875915349cc031c07fe1b3ec)
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 	char inline_name[];
66 } __randomize_layout;
67 
68 #define OFFSETOF_PDE_NAME offsetof(struct proc_dir_entry, inline_name)
69 #define SIZEOF_PDE_SLOT					\
70 	(OFFSETOF_PDE_NAME + 34 <= 64 ? 64 :		\
71 	 OFFSETOF_PDE_NAME + 34 <= 128 ? 128 :		\
72 	 OFFSETOF_PDE_NAME + 34 <= 192 ? 192 :		\
73 	 OFFSETOF_PDE_NAME + 34 <= 256 ? 256 :		\
74 	 OFFSETOF_PDE_NAME + 34 <= 512 ? 512 :		\
75 	 0)
76 
77 #define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE_SLOT - OFFSETOF_PDE_NAME)
78 
79 extern struct kmem_cache *proc_dir_entry_cache;
80 void pde_free(struct proc_dir_entry *pde);
81 
82 union proc_op {
83 	int (*proc_get_link)(struct dentry *, struct path *);
84 	int (*proc_show)(struct seq_file *m,
85 		struct pid_namespace *ns, struct pid *pid,
86 		struct task_struct *task);
87 };
88 
89 struct proc_inode {
90 	struct pid *pid;
91 	unsigned int fd;
92 	union proc_op op;
93 	struct proc_dir_entry *pde;
94 	struct ctl_table_header *sysctl;
95 	struct ctl_table *sysctl_entry;
96 	struct hlist_node sysctl_inodes;
97 	const struct proc_ns_operations *ns_ops;
98 	struct inode vfs_inode;
99 } __randomize_layout;
100 
101 /*
102  * General functions
103  */
104 static inline struct proc_inode *PROC_I(const struct inode *inode)
105 {
106 	return container_of(inode, struct proc_inode, vfs_inode);
107 }
108 
109 static inline struct proc_dir_entry *PDE(const struct inode *inode)
110 {
111 	return PROC_I(inode)->pde;
112 }
113 
114 static inline void *__PDE_DATA(const struct inode *inode)
115 {
116 	return PDE(inode)->data;
117 }
118 
119 static inline struct pid *proc_pid(struct inode *inode)
120 {
121 	return PROC_I(inode)->pid;
122 }
123 
124 static inline struct task_struct *get_proc_task(struct inode *inode)
125 {
126 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
127 }
128 
129 void task_dump_owner(struct task_struct *task, umode_t mode,
130 		     kuid_t *ruid, kgid_t *rgid);
131 
132 unsigned name_to_int(const struct qstr *qstr);
133 /*
134  * Offset of the first process in the /proc root directory..
135  */
136 #define FIRST_PROCESS_ENTRY 256
137 
138 /* Worst case buffer size needed for holding an integer. */
139 #define PROC_NUMBUF 13
140 
141 /*
142  * array.c
143  */
144 extern const struct file_operations proc_tid_children_operations;
145 
146 extern void proc_task_name(struct seq_file *m, struct task_struct *p,
147 			   bool escape);
148 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
149 			 struct pid *, struct task_struct *);
150 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
151 			  struct pid *, struct task_struct *);
152 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
153 			   struct pid *, struct task_struct *);
154 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
155 			  struct pid *, struct task_struct *);
156 
157 /*
158  * base.c
159  */
160 extern const struct dentry_operations pid_dentry_operations;
161 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
162 extern int proc_setattr(struct dentry *, struct iattr *);
163 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
164 extern void pid_update_inode(struct task_struct *, struct inode *);
165 extern int pid_delete_dentry(const struct dentry *);
166 extern int proc_pid_readdir(struct file *, struct dir_context *);
167 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
168 extern loff_t mem_lseek(struct file *, loff_t, int);
169 
170 /* Lookups */
171 typedef struct dentry *instantiate_t(struct dentry *,
172 				     struct task_struct *, const void *);
173 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int,
174 			   instantiate_t, struct task_struct *, const void *);
175 
176 /*
177  * generic.c
178  */
179 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
180 		struct proc_dir_entry **parent, void *data);
181 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
182 		struct proc_dir_entry *dp);
183 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
184 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
185 extern int proc_readdir(struct file *, struct dir_context *);
186 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
187 
188 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
189 {
190 	refcount_inc(&pde->refcnt);
191 	return pde;
192 }
193 extern void pde_put(struct proc_dir_entry *);
194 
195 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
196 {
197 	return S_ISDIR(pde->mode) && !pde->proc_iops;
198 }
199 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *);
200 
201 /*
202  * inode.c
203  */
204 struct pde_opener {
205 	struct file *file;
206 	struct list_head lh;
207 	bool closing;
208 	struct completion *c;
209 } __randomize_layout;
210 extern const struct inode_operations proc_link_inode_operations;
211 
212 extern const struct inode_operations proc_pid_link_inode_operations;
213 
214 void proc_init_kmemcache(void);
215 void set_proc_pid_nlink(void);
216 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
217 extern int proc_fill_super(struct super_block *, void *data, int flags);
218 extern void proc_entry_rundown(struct proc_dir_entry *);
219 
220 /*
221  * proc_namespaces.c
222  */
223 extern const struct inode_operations proc_ns_dir_inode_operations;
224 extern const struct file_operations proc_ns_dir_operations;
225 
226 /*
227  * proc_net.c
228  */
229 extern const struct file_operations proc_net_operations;
230 extern const struct inode_operations proc_net_inode_operations;
231 
232 #ifdef CONFIG_NET
233 extern int proc_net_init(void);
234 #else
235 static inline int proc_net_init(void) { return 0; }
236 #endif
237 
238 /*
239  * proc_self.c
240  */
241 extern int proc_setup_self(struct super_block *);
242 
243 /*
244  * proc_thread_self.c
245  */
246 extern int proc_setup_thread_self(struct super_block *);
247 extern void proc_thread_self_init(void);
248 
249 /*
250  * proc_sysctl.c
251  */
252 #ifdef CONFIG_PROC_SYSCTL
253 extern int proc_sys_init(void);
254 extern void proc_sys_evict_inode(struct inode *inode,
255 				 struct ctl_table_header *head);
256 #else
257 static inline void proc_sys_init(void) { }
258 static inline void proc_sys_evict_inode(struct  inode *inode,
259 					struct ctl_table_header *head) { }
260 #endif
261 
262 /*
263  * proc_tty.c
264  */
265 #ifdef CONFIG_TTY
266 extern void proc_tty_init(void);
267 #else
268 static inline void proc_tty_init(void) {}
269 #endif
270 
271 /*
272  * root.c
273  */
274 extern struct proc_dir_entry proc_root;
275 extern int proc_parse_options(char *options, struct pid_namespace *pid);
276 
277 extern void proc_self_init(void);
278 extern int proc_remount(struct super_block *, int *, char *);
279 
280 /*
281  * task_[no]mmu.c
282  */
283 struct mem_size_stats;
284 struct proc_maps_private {
285 	struct inode *inode;
286 	struct task_struct *task;
287 	struct mm_struct *mm;
288 	struct mem_size_stats *rollup;
289 #ifdef CONFIG_MMU
290 	struct vm_area_struct *tail_vma;
291 #endif
292 #ifdef CONFIG_NUMA
293 	struct mempolicy *task_mempolicy;
294 #endif
295 } __randomize_layout;
296 
297 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
298 
299 extern const struct file_operations proc_pid_maps_operations;
300 extern const struct file_operations proc_tid_maps_operations;
301 extern const struct file_operations proc_pid_numa_maps_operations;
302 extern const struct file_operations proc_tid_numa_maps_operations;
303 extern const struct file_operations proc_pid_smaps_operations;
304 extern const struct file_operations proc_pid_smaps_rollup_operations;
305 extern const struct file_operations proc_tid_smaps_operations;
306 extern const struct file_operations proc_clear_refs_operations;
307 extern const struct file_operations proc_pagemap_operations;
308 
309 extern unsigned long task_vsize(struct mm_struct *);
310 extern unsigned long task_statm(struct mm_struct *,
311 				unsigned long *, unsigned long *,
312 				unsigned long *, unsigned long *);
313 extern void task_mem(struct seq_file *, struct mm_struct *);
314