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
18struct ctl_table_header;
19struct mempolicy;
20
21/*
22 * This is not completely implemented yet. The idea is to
23 * create an in-memory tree (like the actual /proc filesystem
24 * tree) of these proc_dir_entries, so that we can dynamically
25 * add new files to /proc.
26 *
27 * parent/subdir are used for the directory structure (every /proc file has a
28 * parent, but "subdir" is empty for all non-directory entries).
29 * subdir_node is used to build the rb tree "subdir" of the parent.
30 */
31struct proc_dir_entry {
32	unsigned int low_ino;
33	umode_t mode;
34	nlink_t nlink;
35	kuid_t uid;
36	kgid_t gid;
37	loff_t size;
38	const struct inode_operations *proc_iops;
39	const struct file_operations *proc_fops;
40	struct proc_dir_entry *parent;
41	struct rb_root subdir;
42	struct rb_node subdir_node;
43	void *data;
44	atomic_t count;		/* use count */
45	atomic_t in_use;	/* number of callers into module in progress; */
46			/* negative -> it's going away RSN */
47	struct completion *pde_unload_completion;
48	struct list_head pde_openers;	/* who did ->open, but not ->release */
49	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
50	u8 namelen;
51	char name[];
52};
53
54union proc_op {
55	int (*proc_get_link)(struct dentry *, struct path *);
56	int (*proc_show)(struct seq_file *m,
57		struct pid_namespace *ns, struct pid *pid,
58		struct task_struct *task);
59};
60
61struct proc_inode {
62	struct pid *pid;
63	int fd;
64	union proc_op op;
65	struct proc_dir_entry *pde;
66	struct ctl_table_header *sysctl;
67	struct ctl_table *sysctl_entry;
68	const struct proc_ns_operations *ns_ops;
69	struct inode vfs_inode;
70};
71
72/*
73 * General functions
74 */
75static inline struct proc_inode *PROC_I(const struct inode *inode)
76{
77	return container_of(inode, struct proc_inode, vfs_inode);
78}
79
80static inline struct proc_dir_entry *PDE(const struct inode *inode)
81{
82	return PROC_I(inode)->pde;
83}
84
85static inline void *__PDE_DATA(const struct inode *inode)
86{
87	return PDE(inode)->data;
88}
89
90static inline struct pid *proc_pid(struct inode *inode)
91{
92	return PROC_I(inode)->pid;
93}
94
95static inline struct task_struct *get_proc_task(struct inode *inode)
96{
97	return get_pid_task(proc_pid(inode), PIDTYPE_PID);
98}
99
100static inline int task_dumpable(struct task_struct *task)
101{
102	int dumpable = 0;
103	struct mm_struct *mm;
104
105	task_lock(task);
106	mm = task->mm;
107	if (mm)
108		dumpable = get_dumpable(mm);
109	task_unlock(task);
110	if (dumpable == SUID_DUMP_USER)
111		return 1;
112	return 0;
113}
114
115static inline unsigned name_to_int(const struct qstr *qstr)
116{
117	const char *name = qstr->name;
118	int len = qstr->len;
119	unsigned n = 0;
120
121	if (len > 1 && *name == '0')
122		goto out;
123	while (len-- > 0) {
124		unsigned c = *name++ - '0';
125		if (c > 9)
126			goto out;
127		if (n >= (~0U-9)/10)
128			goto out;
129		n *= 10;
130		n += c;
131	}
132	return n;
133out:
134	return ~0U;
135}
136
137/*
138 * Offset of the first process in the /proc root directory..
139 */
140#define FIRST_PROCESS_ENTRY 256
141
142/* Worst case buffer size needed for holding an integer. */
143#define PROC_NUMBUF 13
144
145/*
146 * array.c
147 */
148extern const struct file_operations proc_tid_children_operations;
149
150extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
151			 struct pid *, struct task_struct *);
152extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
153			  struct pid *, struct task_struct *);
154extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
155			   struct pid *, struct task_struct *);
156extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
157			  struct pid *, struct task_struct *);
158
159/*
160 * base.c
161 */
162extern const struct dentry_operations pid_dentry_operations;
163extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
164extern int proc_setattr(struct dentry *, struct iattr *);
165extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *);
166extern int pid_revalidate(struct dentry *, unsigned int);
167extern int pid_delete_dentry(const struct dentry *);
168extern int proc_pid_readdir(struct file *, struct dir_context *);
169extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
170extern loff_t mem_lseek(struct file *, loff_t, int);
171
172/* Lookups */
173typedef int instantiate_t(struct inode *, struct dentry *,
174				     struct task_struct *, const void *);
175extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
176			   instantiate_t, struct task_struct *, const void *);
177
178/*
179 * generic.c
180 */
181extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
182extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
183				     struct dentry *);
184extern int proc_readdir(struct file *, struct dir_context *);
185extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
186
187static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
188{
189	atomic_inc(&pde->count);
190	return pde;
191}
192extern void pde_put(struct proc_dir_entry *);
193
194static inline bool is_empty_pde(const struct proc_dir_entry *pde)
195{
196	return S_ISDIR(pde->mode) && !pde->proc_iops;
197}
198struct proc_dir_entry *proc_create_mount_point(const char *name);
199
200/*
201 * inode.c
202 */
203struct pde_opener {
204	struct file *file;
205	struct list_head lh;
206	int closing;
207	struct completion *c;
208};
209extern const struct inode_operations proc_link_inode_operations;
210
211extern const struct inode_operations proc_pid_link_inode_operations;
212
213extern void proc_init_inodecache(void);
214extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
215extern int proc_fill_super(struct super_block *);
216extern void proc_entry_rundown(struct proc_dir_entry *);
217
218/*
219 * proc_namespaces.c
220 */
221extern const struct inode_operations proc_ns_dir_inode_operations;
222extern const struct file_operations proc_ns_dir_operations;
223
224/*
225 * proc_net.c
226 */
227extern const struct file_operations proc_net_operations;
228extern const struct inode_operations proc_net_inode_operations;
229
230#ifdef CONFIG_NET
231extern int proc_net_init(void);
232#else
233static inline int proc_net_init(void) { return 0; }
234#endif
235
236/*
237 * proc_self.c
238 */
239extern int proc_setup_self(struct super_block *);
240
241/*
242 * proc_thread_self.c
243 */
244extern int proc_setup_thread_self(struct super_block *);
245extern void proc_thread_self_init(void);
246
247/*
248 * proc_sysctl.c
249 */
250#ifdef CONFIG_PROC_SYSCTL
251extern int proc_sys_init(void);
252extern void sysctl_head_put(struct ctl_table_header *);
253#else
254static inline void proc_sys_init(void) { }
255static inline void sysctl_head_put(struct ctl_table_header *head) { }
256#endif
257
258/*
259 * proc_tty.c
260 */
261#ifdef CONFIG_TTY
262extern void proc_tty_init(void);
263#else
264static inline void proc_tty_init(void) {}
265#endif
266
267/*
268 * root.c
269 */
270extern struct proc_dir_entry proc_root;
271
272extern void proc_self_init(void);
273extern int proc_remount(struct super_block *, int *, char *);
274
275/*
276 * task_[no]mmu.c
277 */
278struct proc_maps_private {
279	struct inode *inode;
280	struct task_struct *task;
281	struct mm_struct *mm;
282#ifdef CONFIG_MMU
283	struct vm_area_struct *tail_vma;
284#endif
285#ifdef CONFIG_NUMA
286	struct mempolicy *task_mempolicy;
287#endif
288};
289
290struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
291
292extern const struct file_operations proc_pid_maps_operations;
293extern const struct file_operations proc_tid_maps_operations;
294extern const struct file_operations proc_pid_numa_maps_operations;
295extern const struct file_operations proc_tid_numa_maps_operations;
296extern const struct file_operations proc_pid_smaps_operations;
297extern const struct file_operations proc_tid_smaps_operations;
298extern const struct file_operations proc_clear_refs_operations;
299extern const struct file_operations proc_pagemap_operations;
300
301extern unsigned long task_vsize(struct mm_struct *);
302extern unsigned long task_statm(struct mm_struct *,
303				unsigned long *, unsigned long *,
304				unsigned long *, unsigned long *);
305extern void task_mem(struct seq_file *, struct mm_struct *);
306