2 * linux/fs/proc/inode.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/sched.h>
8 #include <linux/proc_fs.h>
9 #include <linux/kernel.h>
11 #include <linux/string.h>
12 #include <linux/stat.h>
13 #include <linux/file.h>
14 #include <linux/locks.h>
15 #include <linux/limits.h>
16 #define __NO_VERSION__
17 #include <linux/module.h>
18 #include <linux/smp_lock.h>
20 #include <asm/system.h>
21 #include <asm/uaccess.h>
23 extern void free_proc_entry(struct proc_dir_entry *);
25 static inline struct proc_dir_entry * de_get(struct proc_dir_entry *de)
28 atomic_inc(&de->count);
33 * Decrements the use count and checks for deferred deletion.
35 static void de_put(struct proc_dir_entry *de)
39 if (!atomic_read(&de->count)) {
40 printk("de_put: entry %s already free!\n", de->name);
45 if (atomic_dec_and_test(&de->count)) {
47 printk("de_put: deferred delete of %s\n",
57 * Decrement the use count of the proc_dir_entry.
59 static void proc_delete_inode(struct inode *inode)
61 struct proc_dir_entry *de = inode->u.generic_ip;
63 inode->i_state = I_CLEAR;
65 if (PROC_INODE_PROPER(inode)) {
66 proc_pid_delete_inode(inode);
71 __MOD_DEC_USE_COUNT(de->owner);
76 struct vfsmount *proc_mnt;
78 static void proc_read_inode(struct inode * inode)
80 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
83 static int proc_statfs(struct super_block *sb, struct statfs *buf)
85 buf->f_type = PROC_SUPER_MAGIC;
86 buf->f_bsize = PAGE_SIZE/sizeof(long);
90 buf->f_namelen = NAME_MAX;
94 static struct super_operations proc_sops = {
95 read_inode: proc_read_inode,
96 put_inode: force_delete,
97 delete_inode: proc_delete_inode,
102 static int parse_options(char *options,uid_t *uid,gid_t *gid)
104 char *this_char,*value;
108 if (!options) return 1;
109 for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
110 if ((value = strchr(this_char,'=')) != NULL)
112 if (!strcmp(this_char,"uid")) {
113 if (!value || !*value)
115 *uid = simple_strtoul(value,&value,0);
119 else if (!strcmp(this_char,"gid")) {
120 if (!value || !*value)
122 *gid = simple_strtoul(value,&value,0);
131 struct inode * proc_get_inode(struct super_block * sb, int ino,
132 struct proc_dir_entry * de)
134 struct inode * inode;
137 * Increment the use count so the dir entry can't disappear.
141 /* shouldn't ever happen */
142 if (de && de->deleted)
143 printk("proc_iget: using deleted entry %s, count=%d\n", de->name, atomic_read(&de->count));
146 inode = iget(sb, ino);
150 inode->u.generic_ip = (void *) de;
153 inode->i_mode = de->mode;
154 inode->i_uid = de->uid;
155 inode->i_gid = de->gid;
158 inode->i_size = de->size;
160 inode->i_nlink = de->nlink;
162 __MOD_INC_USE_COUNT(de->owner);
164 inode->i_op = de->proc_iops;
166 inode->i_fop = de->proc_fops;
167 else if (S_ISBLK(de->mode)||S_ISCHR(de->mode)||S_ISFIFO(de->mode))
168 init_special_inode(inode,de->mode,kdev_t_to_nr(de->rdev));
179 struct super_block *proc_read_super(struct super_block *s,void *data,
182 struct inode * root_inode;
183 struct task_struct *p;
185 s->s_blocksize = 1024;
186 s->s_blocksize_bits = 10;
187 s->s_magic = PROC_SUPER_MAGIC;
188 s->s_op = &proc_sops;
189 s->s_maxbytes = ~0UL;
191 root_inode = proc_get_inode(s, PROC_ROOT_INO, &proc_root);
195 * Fixup the root inode's nlink value
197 read_lock(&tasklist_lock);
198 for_each_task(p) if (p->pid) root_inode->i_nlink++;
199 read_unlock(&tasklist_lock);
200 s->s_root = d_alloc_root(root_inode);
203 parse_options(data, &root_inode->i_uid, &root_inode->i_gid);
207 printk("proc_read_super: get root inode failed\n");
211 MODULE_LICENSE("GPL");