xref: /openbmc/linux/fs/proc/internal.h (revision 82e6fdd6)
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 	/*
35 	 * number of callers into module in progress;
36 	 * negative -> it's going away RSN
37 	 */
38 	atomic_t in_use;
39 	atomic_t count;		/* use count */
40 	struct list_head pde_openers;	/* who did ->open, but not ->release */
41 	/* protects ->pde_openers and all struct pde_opener instances */
42 	spinlock_t pde_unload_lock;
43 	struct completion *pde_unload_completion;
44 	const struct inode_operations *proc_iops;
45 	const struct file_operations *proc_fops;
46 	void *data;
47 	unsigned int low_ino;
48 	nlink_t nlink;
49 	kuid_t uid;
50 	kgid_t gid;
51 	loff_t size;
52 	struct proc_dir_entry *parent;
53 	struct rb_root_cached subdir;
54 	struct rb_node subdir_node;
55 	umode_t mode;
56 	u8 namelen;
57 	char name[];
58 } __randomize_layout;
59 
60 union proc_op {
61 	int (*proc_get_link)(struct dentry *, struct path *);
62 	int (*proc_show)(struct seq_file *m,
63 		struct pid_namespace *ns, struct pid *pid,
64 		struct task_struct *task);
65 };
66 
67 struct proc_inode {
68 	struct pid *pid;
69 	unsigned int fd;
70 	union proc_op op;
71 	struct proc_dir_entry *pde;
72 	struct ctl_table_header *sysctl;
73 	struct ctl_table *sysctl_entry;
74 	struct hlist_node sysctl_inodes;
75 	const struct proc_ns_operations *ns_ops;
76 	struct inode vfs_inode;
77 } __randomize_layout;
78 
79 /*
80  * General functions
81  */
82 static inline struct proc_inode *PROC_I(const struct inode *inode)
83 {
84 	return container_of(inode, struct proc_inode, vfs_inode);
85 }
86 
87 static inline struct proc_dir_entry *PDE(const struct inode *inode)
88 {
89 	return PROC_I(inode)->pde;
90 }
91 
92 static inline void *__PDE_DATA(const struct inode *inode)
93 {
94 	return PDE(inode)->data;
95 }
96 
97 static inline struct pid *proc_pid(struct inode *inode)
98 {
99 	return PROC_I(inode)->pid;
100 }
101 
102 static inline struct task_struct *get_proc_task(struct inode *inode)
103 {
104 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
105 }
106 
107 void task_dump_owner(struct task_struct *task, umode_t mode,
108 		     kuid_t *ruid, kgid_t *rgid);
109 
110 unsigned name_to_int(const struct qstr *qstr);
111 /*
112  * Offset of the first process in the /proc root directory..
113  */
114 #define FIRST_PROCESS_ENTRY 256
115 
116 /* Worst case buffer size needed for holding an integer. */
117 #define PROC_NUMBUF 13
118 
119 /*
120  * array.c
121  */
122 extern const struct file_operations proc_tid_children_operations;
123 
124 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
125 			 struct pid *, struct task_struct *);
126 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
127 			  struct pid *, struct task_struct *);
128 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
129 			   struct pid *, struct task_struct *);
130 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
131 			  struct pid *, struct task_struct *);
132 
133 /*
134  * base.c
135  */
136 extern const struct dentry_operations pid_dentry_operations;
137 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
138 extern int proc_setattr(struct dentry *, struct iattr *);
139 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
140 extern int pid_revalidate(struct dentry *, unsigned int);
141 extern int pid_delete_dentry(const struct dentry *);
142 extern int proc_pid_readdir(struct file *, struct dir_context *);
143 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
144 extern loff_t mem_lseek(struct file *, loff_t, int);
145 
146 /* Lookups */
147 typedef int instantiate_t(struct inode *, struct dentry *,
148 				     struct task_struct *, const void *);
149 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
150 			   instantiate_t, struct task_struct *, const void *);
151 
152 /*
153  * generic.c
154  */
155 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
156 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
157 extern int proc_readdir(struct file *, struct dir_context *);
158 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
159 
160 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
161 {
162 	atomic_inc(&pde->count);
163 	return pde;
164 }
165 extern void pde_put(struct proc_dir_entry *);
166 
167 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
168 {
169 	return S_ISDIR(pde->mode) && !pde->proc_iops;
170 }
171 
172 /*
173  * inode.c
174  */
175 struct pde_opener {
176 	struct file *file;
177 	struct list_head lh;
178 	bool closing;
179 	struct completion *c;
180 };
181 extern const struct inode_operations proc_link_inode_operations;
182 
183 extern const struct inode_operations proc_pid_link_inode_operations;
184 
185 extern void proc_init_inodecache(void);
186 void set_proc_pid_nlink(void);
187 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
188 extern int proc_fill_super(struct super_block *, void *data, int flags);
189 extern void proc_entry_rundown(struct proc_dir_entry *);
190 
191 /*
192  * proc_namespaces.c
193  */
194 extern const struct inode_operations proc_ns_dir_inode_operations;
195 extern const struct file_operations proc_ns_dir_operations;
196 
197 /*
198  * proc_net.c
199  */
200 extern const struct file_operations proc_net_operations;
201 extern const struct inode_operations proc_net_inode_operations;
202 
203 #ifdef CONFIG_NET
204 extern int proc_net_init(void);
205 #else
206 static inline int proc_net_init(void) { return 0; }
207 #endif
208 
209 /*
210  * proc_self.c
211  */
212 extern int proc_setup_self(struct super_block *);
213 
214 /*
215  * proc_thread_self.c
216  */
217 extern int proc_setup_thread_self(struct super_block *);
218 extern void proc_thread_self_init(void);
219 
220 /*
221  * proc_sysctl.c
222  */
223 #ifdef CONFIG_PROC_SYSCTL
224 extern int proc_sys_init(void);
225 extern void proc_sys_evict_inode(struct inode *inode,
226 				 struct ctl_table_header *head);
227 #else
228 static inline void proc_sys_init(void) { }
229 static inline void proc_sys_evict_inode(struct  inode *inode,
230 					struct ctl_table_header *head) { }
231 #endif
232 
233 /*
234  * proc_tty.c
235  */
236 #ifdef CONFIG_TTY
237 extern void proc_tty_init(void);
238 #else
239 static inline void proc_tty_init(void) {}
240 #endif
241 
242 /*
243  * root.c
244  */
245 extern struct proc_dir_entry proc_root;
246 extern int proc_parse_options(char *options, struct pid_namespace *pid);
247 
248 extern void proc_self_init(void);
249 extern int proc_remount(struct super_block *, int *, char *);
250 
251 /*
252  * task_[no]mmu.c
253  */
254 struct mem_size_stats;
255 struct proc_maps_private {
256 	struct inode *inode;
257 	struct task_struct *task;
258 	struct mm_struct *mm;
259 	struct mem_size_stats *rollup;
260 #ifdef CONFIG_MMU
261 	struct vm_area_struct *tail_vma;
262 #endif
263 #ifdef CONFIG_NUMA
264 	struct mempolicy *task_mempolicy;
265 #endif
266 } __randomize_layout;
267 
268 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
269 
270 extern const struct file_operations proc_pid_maps_operations;
271 extern const struct file_operations proc_tid_maps_operations;
272 extern const struct file_operations proc_pid_numa_maps_operations;
273 extern const struct file_operations proc_tid_numa_maps_operations;
274 extern const struct file_operations proc_pid_smaps_operations;
275 extern const struct file_operations proc_pid_smaps_rollup_operations;
276 extern const struct file_operations proc_tid_smaps_operations;
277 extern const struct file_operations proc_clear_refs_operations;
278 extern const struct file_operations proc_pagemap_operations;
279 
280 extern unsigned long task_vsize(struct mm_struct *);
281 extern unsigned long task_statm(struct mm_struct *,
282 				unsigned long *, unsigned long *,
283 				unsigned long *, unsigned long *);
284 extern void task_mem(struct seq_file *, struct mm_struct *);
285