xref: /openbmc/linux/fs/proc/internal.h (revision 3fc41476)
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 	const struct dentry_operations *proc_dops;
48 	union {
49 		const struct seq_operations *seq_ops;
50 		int (*single_show)(struct seq_file *, void *);
51 	};
52 	proc_write_t write;
53 	void *data;
54 	unsigned int state_size;
55 	unsigned int low_ino;
56 	nlink_t nlink;
57 	kuid_t uid;
58 	kgid_t gid;
59 	loff_t size;
60 	struct proc_dir_entry *parent;
61 	struct rb_root subdir;
62 	struct rb_node subdir_node;
63 	char *name;
64 	umode_t mode;
65 	u8 namelen;
66 	char inline_name[];
67 } __randomize_layout;
68 
69 #define SIZEOF_PDE	(				\
70 	sizeof(struct proc_dir_entry) < 128 ? 128 :	\
71 	sizeof(struct proc_dir_entry) < 192 ? 192 :	\
72 	sizeof(struct proc_dir_entry) < 256 ? 256 :	\
73 	sizeof(struct proc_dir_entry) < 512 ? 512 :	\
74 	0)
75 #define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry))
76 
77 extern struct kmem_cache *proc_dir_entry_cache;
78 void pde_free(struct proc_dir_entry *pde);
79 
80 union proc_op {
81 	int (*proc_get_link)(struct dentry *, struct path *);
82 	int (*proc_show)(struct seq_file *m,
83 		struct pid_namespace *ns, struct pid *pid,
84 		struct task_struct *task);
85 	const char *lsm;
86 };
87 
88 struct proc_inode {
89 	struct pid *pid;
90 	unsigned int fd;
91 	union proc_op op;
92 	struct proc_dir_entry *pde;
93 	struct ctl_table_header *sysctl;
94 	struct ctl_table *sysctl_entry;
95 	struct hlist_node sysctl_inodes;
96 	const struct proc_ns_operations *ns_ops;
97 	struct inode vfs_inode;
98 } __randomize_layout;
99 
100 /*
101  * General functions
102  */
103 static inline struct proc_inode *PROC_I(const struct inode *inode)
104 {
105 	return container_of(inode, struct proc_inode, vfs_inode);
106 }
107 
108 static inline struct proc_dir_entry *PDE(const struct inode *inode)
109 {
110 	return PROC_I(inode)->pde;
111 }
112 
113 static inline void *__PDE_DATA(const struct inode *inode)
114 {
115 	return PDE(inode)->data;
116 }
117 
118 static inline struct pid *proc_pid(const struct inode *inode)
119 {
120 	return PROC_I(inode)->pid;
121 }
122 
123 static inline struct task_struct *get_proc_task(const struct inode *inode)
124 {
125 	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
126 }
127 
128 void task_dump_owner(struct task_struct *task, umode_t mode,
129 		     kuid_t *ruid, kgid_t *rgid);
130 
131 unsigned name_to_int(const struct qstr *qstr);
132 /*
133  * Offset of the first process in the /proc root directory..
134  */
135 #define FIRST_PROCESS_ENTRY 256
136 
137 /* Worst case buffer size needed for holding an integer. */
138 #define PROC_NUMBUF 13
139 
140 /*
141  * array.c
142  */
143 extern const struct file_operations proc_tid_children_operations;
144 
145 extern void proc_task_name(struct seq_file *m, struct task_struct *p,
146 			   bool escape);
147 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
148 			 struct pid *, struct task_struct *);
149 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
150 			  struct pid *, struct task_struct *);
151 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
152 			   struct pid *, struct task_struct *);
153 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
154 			  struct pid *, struct task_struct *);
155 
156 /*
157  * base.c
158  */
159 extern const struct dentry_operations pid_dentry_operations;
160 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
161 extern int proc_setattr(struct dentry *, struct iattr *);
162 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
163 extern void pid_update_inode(struct task_struct *, struct inode *);
164 extern int pid_delete_dentry(const struct dentry *);
165 extern int proc_pid_readdir(struct file *, struct dir_context *);
166 struct dentry *proc_pid_lookup(struct dentry *, unsigned int);
167 extern loff_t mem_lseek(struct file *, loff_t, int);
168 
169 /* Lookups */
170 typedef struct dentry *instantiate_t(struct dentry *,
171 				     struct task_struct *, const void *);
172 bool proc_fill_cache(struct file *, struct dir_context *, const char *, unsigned int,
173 			   instantiate_t, struct task_struct *, const void *);
174 
175 /*
176  * generic.c
177  */
178 struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
179 		struct proc_dir_entry **parent, void *data);
180 struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
181 		struct proc_dir_entry *dp);
182 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
183 struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *);
184 extern int proc_readdir(struct file *, struct dir_context *);
185 int proc_readdir_de(struct file *, struct dir_context *, struct proc_dir_entry *);
186 
187 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
188 {
189 	refcount_inc(&pde->refcnt);
190 	return pde;
191 }
192 extern void pde_put(struct proc_dir_entry *);
193 
194 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
195 {
196 	return S_ISDIR(pde->mode) && !pde->proc_iops;
197 }
198 extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, loff_t *);
199 
200 /*
201  * inode.c
202  */
203 struct pde_opener {
204 	struct file *file;
205 	struct list_head lh;
206 	bool closing;
207 	struct completion *c;
208 } __randomize_layout;
209 extern const struct inode_operations proc_link_inode_operations;
210 extern const struct inode_operations proc_pid_link_inode_operations;
211 extern const struct super_operations proc_sops;
212 
213 void proc_init_kmemcache(void);
214 void set_proc_pid_nlink(void);
215 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
216 extern void proc_entry_rundown(struct proc_dir_entry *);
217 
218 /*
219  * proc_namespaces.c
220  */
221 extern const struct inode_operations proc_ns_dir_inode_operations;
222 extern const struct file_operations proc_ns_dir_operations;
223 
224 /*
225  * proc_net.c
226  */
227 extern const struct file_operations proc_net_operations;
228 extern const struct inode_operations proc_net_inode_operations;
229 
230 #ifdef CONFIG_NET
231 extern int proc_net_init(void);
232 #else
233 static inline int proc_net_init(void) { return 0; }
234 #endif
235 
236 /*
237  * proc_self.c
238  */
239 extern int proc_setup_self(struct super_block *);
240 
241 /*
242  * proc_thread_self.c
243  */
244 extern int proc_setup_thread_self(struct super_block *);
245 extern void proc_thread_self_init(void);
246 
247 /*
248  * proc_sysctl.c
249  */
250 #ifdef CONFIG_PROC_SYSCTL
251 extern int proc_sys_init(void);
252 extern void proc_sys_evict_inode(struct inode *inode,
253 				 struct ctl_table_header *head);
254 #else
255 static inline void proc_sys_init(void) { }
256 static inline void proc_sys_evict_inode(struct  inode *inode,
257 					struct ctl_table_header *head) { }
258 #endif
259 
260 /*
261  * proc_tty.c
262  */
263 #ifdef CONFIG_TTY
264 extern void proc_tty_init(void);
265 #else
266 static inline void proc_tty_init(void) {}
267 #endif
268 
269 /*
270  * root.c
271  */
272 extern struct proc_dir_entry proc_root;
273 
274 extern void proc_self_init(void);
275 
276 /*
277  * task_[no]mmu.c
278  */
279 struct mem_size_stats;
280 struct proc_maps_private {
281 	struct inode *inode;
282 	struct task_struct *task;
283 	struct mm_struct *mm;
284 #ifdef CONFIG_MMU
285 	struct vm_area_struct *tail_vma;
286 #endif
287 #ifdef CONFIG_NUMA
288 	struct mempolicy *task_mempolicy;
289 #endif
290 } __randomize_layout;
291 
292 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
293 
294 extern const struct file_operations proc_pid_maps_operations;
295 extern const struct file_operations proc_pid_numa_maps_operations;
296 extern const struct file_operations proc_pid_smaps_operations;
297 extern const struct file_operations proc_pid_smaps_rollup_operations;
298 extern const struct file_operations proc_clear_refs_operations;
299 extern const struct file_operations proc_pagemap_operations;
300 
301 extern unsigned long task_vsize(struct mm_struct *);
302 extern unsigned long task_statm(struct mm_struct *,
303 				unsigned long *, unsigned long *,
304 				unsigned long *, unsigned long *);
305 extern void task_mem(struct seq_file *, struct mm_struct *);
306