xref: /openbmc/linux/fs/proc/internal.h (revision 4cff79e9)
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 	void *data;
48 	unsigned int low_ino;
49 	nlink_t nlink;
50 	kuid_t uid;
51 	kgid_t gid;
52 	loff_t size;
53 	struct proc_dir_entry *parent;
54 	struct rb_root subdir;
55 	struct rb_node subdir_node;
56 	char *name;
57 	umode_t mode;
58 	u8 namelen;
59 #ifdef CONFIG_64BIT
60 #define SIZEOF_PDE_INLINE_NAME	(192-139)
61 #else
62 #define SIZEOF_PDE_INLINE_NAME	(128-87)
63 #endif
64 	char inline_name[SIZEOF_PDE_INLINE_NAME];
65 } __randomize_layout;
66 
67 extern struct kmem_cache *proc_dir_entry_cache;
68 void pde_free(struct proc_dir_entry *pde);
69 
70 union proc_op {
71 	int (*proc_get_link)(struct dentry *, struct path *);
72 	int (*proc_show)(struct seq_file *m,
73 		struct pid_namespace *ns, struct pid *pid,
74 		struct task_struct *task);
75 };
76 
77 struct proc_inode {
78 	struct pid *pid;
79 	unsigned int fd;
80 	union proc_op op;
81 	struct proc_dir_entry *pde;
82 	struct ctl_table_header *sysctl;
83 	struct ctl_table *sysctl_entry;
84 	struct hlist_node sysctl_inodes;
85 	const struct proc_ns_operations *ns_ops;
86 	struct inode vfs_inode;
87 } __randomize_layout;
88 
89 /*
90  * General functions
91  */
92 static inline struct proc_inode *PROC_I(const struct inode *inode)
93 {
94 	return container_of(inode, struct proc_inode, vfs_inode);
95 }
96 
97 static inline struct proc_dir_entry *PDE(const struct inode *inode)
98 {
99 	return PROC_I(inode)->pde;
100 }
101 
102 static inline void *__PDE_DATA(const struct inode *inode)
103 {
104 	return PDE(inode)->data;
105 }
106 
107 static inline struct pid *proc_pid(struct inode *inode)
108 {
109 	return PROC_I(inode)->pid;
110 }
111 
112 static inline struct task_struct *get_proc_task(struct inode *inode)
113 {
114 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
115 }
116 
117 void task_dump_owner(struct task_struct *task, umode_t mode,
118 		     kuid_t *ruid, kgid_t *rgid);
119 
120 unsigned name_to_int(const struct qstr *qstr);
121 /*
122  * Offset of the first process in the /proc root directory..
123  */
124 #define FIRST_PROCESS_ENTRY 256
125 
126 /* Worst case buffer size needed for holding an integer. */
127 #define PROC_NUMBUF 13
128 
129 /*
130  * array.c
131  */
132 extern const struct file_operations proc_tid_children_operations;
133 
134 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
135 			 struct pid *, struct task_struct *);
136 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
137 			  struct pid *, struct task_struct *);
138 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
139 			   struct pid *, struct task_struct *);
140 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
141 			  struct pid *, struct task_struct *);
142 
143 /*
144  * base.c
145  */
146 extern const struct dentry_operations pid_dentry_operations;
147 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
148 extern int proc_setattr(struct dentry *, struct iattr *);
149 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
150 extern int pid_revalidate(struct dentry *, unsigned int);
151 extern int pid_delete_dentry(const struct dentry *);
152 extern int proc_pid_readdir(struct file *, struct dir_context *);
153 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
154 extern loff_t mem_lseek(struct file *, loff_t, int);
155 
156 /* Lookups */
157 typedef int instantiate_t(struct inode *, struct dentry *,
158 				     struct task_struct *, const void *);
159 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
160 			   instantiate_t, struct task_struct *, const void *);
161 
162 /*
163  * generic.c
164  */
165 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
166 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
167 extern int proc_readdir(struct file *, struct dir_context *);
168 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
169 
170 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
171 {
172 	refcount_inc(&pde->refcnt);
173 	return pde;
174 }
175 extern void pde_put(struct proc_dir_entry *);
176 
177 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
178 {
179 	return S_ISDIR(pde->mode) && !pde->proc_iops;
180 }
181 
182 /*
183  * inode.c
184  */
185 struct pde_opener {
186 	struct file *file;
187 	struct list_head lh;
188 	bool closing;
189 	struct completion *c;
190 } __randomize_layout;
191 extern const struct inode_operations proc_link_inode_operations;
192 
193 extern const struct inode_operations proc_pid_link_inode_operations;
194 
195 void proc_init_kmemcache(void);
196 void set_proc_pid_nlink(void);
197 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
198 extern int proc_fill_super(struct super_block *, void *data, int flags);
199 extern void proc_entry_rundown(struct proc_dir_entry *);
200 
201 /*
202  * proc_namespaces.c
203  */
204 extern const struct inode_operations proc_ns_dir_inode_operations;
205 extern const struct file_operations proc_ns_dir_operations;
206 
207 /*
208  * proc_net.c
209  */
210 extern const struct file_operations proc_net_operations;
211 extern const struct inode_operations proc_net_inode_operations;
212 
213 #ifdef CONFIG_NET
214 extern int proc_net_init(void);
215 #else
216 static inline int proc_net_init(void) { return 0; }
217 #endif
218 
219 /*
220  * proc_self.c
221  */
222 extern int proc_setup_self(struct super_block *);
223 
224 /*
225  * proc_thread_self.c
226  */
227 extern int proc_setup_thread_self(struct super_block *);
228 extern void proc_thread_self_init(void);
229 
230 /*
231  * proc_sysctl.c
232  */
233 #ifdef CONFIG_PROC_SYSCTL
234 extern int proc_sys_init(void);
235 extern void proc_sys_evict_inode(struct inode *inode,
236 				 struct ctl_table_header *head);
237 #else
238 static inline void proc_sys_init(void) { }
239 static inline void proc_sys_evict_inode(struct  inode *inode,
240 					struct ctl_table_header *head) { }
241 #endif
242 
243 /*
244  * proc_tty.c
245  */
246 #ifdef CONFIG_TTY
247 extern void proc_tty_init(void);
248 #else
249 static inline void proc_tty_init(void) {}
250 #endif
251 
252 /*
253  * root.c
254  */
255 extern struct proc_dir_entry proc_root;
256 extern int proc_parse_options(char *options, struct pid_namespace *pid);
257 
258 extern void proc_self_init(void);
259 extern int proc_remount(struct super_block *, int *, char *);
260 
261 /*
262  * task_[no]mmu.c
263  */
264 struct mem_size_stats;
265 struct proc_maps_private {
266 	struct inode *inode;
267 	struct task_struct *task;
268 	struct mm_struct *mm;
269 	struct mem_size_stats *rollup;
270 #ifdef CONFIG_MMU
271 	struct vm_area_struct *tail_vma;
272 #endif
273 #ifdef CONFIG_NUMA
274 	struct mempolicy *task_mempolicy;
275 #endif
276 } __randomize_layout;
277 
278 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
279 
280 extern const struct file_operations proc_pid_maps_operations;
281 extern const struct file_operations proc_tid_maps_operations;
282 extern const struct file_operations proc_pid_numa_maps_operations;
283 extern const struct file_operations proc_tid_numa_maps_operations;
284 extern const struct file_operations proc_pid_smaps_operations;
285 extern const struct file_operations proc_pid_smaps_rollup_operations;
286 extern const struct file_operations proc_tid_smaps_operations;
287 extern const struct file_operations proc_clear_refs_operations;
288 extern const struct file_operations proc_pagemap_operations;
289 
290 extern unsigned long task_vsize(struct mm_struct *);
291 extern unsigned long task_statm(struct mm_struct *,
292 				unsigned long *, unsigned long *,
293 				unsigned long *, unsigned long *);
294 extern void task_mem(struct seq_file *, struct mm_struct *);
295