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-rw-r--r--fs/proc/inode.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
new file mode 100644
index 0000000..133c286
--- /dev/null
+++ b/fs/proc/inode.c
@@ -0,0 +1,218 @@
+/*
+ * linux/fs/proc/inode.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/time.h>
+#include <linux/proc_fs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/file.h>
+#include <linux/limits.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/smp_lock.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+extern void free_proc_entry(struct proc_dir_entry *);
+
+static inline struct proc_dir_entry * de_get(struct proc_dir_entry *de)
+{
+ if (de)
+ atomic_inc(&de->count);
+ return de;
+}
+
+/*
+ * Decrements the use count and checks for deferred deletion.
+ */
+static void de_put(struct proc_dir_entry *de)
+{
+ if (de) {
+ lock_kernel();
+ if (!atomic_read(&de->count)) {
+ printk("de_put: entry %s already free!\n", de->name);
+ unlock_kernel();
+ return;
+ }
+
+ if (atomic_dec_and_test(&de->count)) {
+ if (de->deleted) {
+ printk("de_put: deferred delete of %s\n",
+ de->name);
+ free_proc_entry(de);
+ }
+ }
+ unlock_kernel();
+ }
+}
+
+/*
+ * Decrement the use count of the proc_dir_entry.
+ */
+static void proc_delete_inode(struct inode *inode)
+{
+ struct proc_dir_entry *de;
+ struct task_struct *tsk;
+
+ /* Let go of any associated process */
+ tsk = PROC_I(inode)->task;
+ if (tsk)
+ put_task_struct(tsk);
+
+ /* Let go of any associated proc directory entry */
+ de = PROC_I(inode)->pde;
+ if (de) {
+ if (de->owner)
+ module_put(de->owner);
+ de_put(de);
+ }
+ clear_inode(inode);
+}
+
+struct vfsmount *proc_mnt;
+
+static void proc_read_inode(struct inode * inode)
+{
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+}
+
+static kmem_cache_t * proc_inode_cachep;
+
+static struct inode *proc_alloc_inode(struct super_block *sb)
+{
+ struct proc_inode *ei;
+ struct inode *inode;
+
+ ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, SLAB_KERNEL);
+ if (!ei)
+ return NULL;
+ ei->task = NULL;
+ ei->type = 0;
+ ei->op.proc_get_link = NULL;
+ ei->pde = NULL;
+ inode = &ei->vfs_inode;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ return inode;
+}
+
+static void proc_destroy_inode(struct inode *inode)
+{
+ kmem_cache_free(proc_inode_cachep, PROC_I(inode));
+}
+
+static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
+{
+ struct proc_inode *ei = (struct proc_inode *) foo;
+
+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR)
+ inode_init_once(&ei->vfs_inode);
+}
+
+int __init proc_init_inodecache(void)
+{
+ proc_inode_cachep = kmem_cache_create("proc_inode_cache",
+ sizeof(struct proc_inode),
+ 0, SLAB_RECLAIM_ACCOUNT,
+ init_once, NULL);
+ if (proc_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static int proc_remount(struct super_block *sb, int *flags, char *data)
+{
+ *flags |= MS_NODIRATIME;
+ return 0;
+}
+
+static struct super_operations proc_sops = {
+ .alloc_inode = proc_alloc_inode,
+ .destroy_inode = proc_destroy_inode,
+ .read_inode = proc_read_inode,
+ .drop_inode = generic_delete_inode,
+ .delete_inode = proc_delete_inode,
+ .statfs = simple_statfs,
+ .remount_fs = proc_remount,
+};
+
+struct inode *proc_get_inode(struct super_block *sb, unsigned int ino,
+ struct proc_dir_entry *de)
+{
+ struct inode * inode;
+
+ /*
+ * Increment the use count so the dir entry can't disappear.
+ */
+ de_get(de);
+
+ WARN_ON(de && de->deleted);
+
+ inode = iget(sb, ino);
+ if (!inode)
+ goto out_fail;
+
+ PROC_I(inode)->pde = de;
+ if (de) {
+ if (de->mode) {
+ inode->i_mode = de->mode;
+ inode->i_uid = de->uid;
+ inode->i_gid = de->gid;
+ }
+ if (de->size)
+ inode->i_size = de->size;
+ if (de->nlink)
+ inode->i_nlink = de->nlink;
+ if (!try_module_get(de->owner))
+ goto out_fail;
+ if (de->proc_iops)
+ inode->i_op = de->proc_iops;
+ if (de->proc_fops)
+ inode->i_fop = de->proc_fops;
+ }
+
+out:
+ return inode;
+
+out_fail:
+ de_put(de);
+ goto out;
+}
+
+int proc_fill_super(struct super_block *s, void *data, int silent)
+{
+ struct inode * root_inode;
+
+ s->s_flags |= MS_NODIRATIME;
+ s->s_blocksize = 1024;
+ s->s_blocksize_bits = 10;
+ s->s_magic = PROC_SUPER_MAGIC;
+ s->s_op = &proc_sops;
+ s->s_time_gran = 1;
+
+ root_inode = proc_get_inode(s, PROC_ROOT_INO, &proc_root);
+ if (!root_inode)
+ goto out_no_root;
+ /*
+ * Fixup the root inode's nlink value
+ */
+ root_inode->i_nlink += nr_processes();
+ root_inode->i_uid = 0;
+ root_inode->i_gid = 0;
+ s->s_root = d_alloc_root(root_inode);
+ if (!s->s_root)
+ goto out_no_root;
+ return 0;
+
+out_no_root:
+ printk("proc_read_super: get root inode failed\n");
+ iput(root_inode);
+ return -ENOMEM;
+}
+MODULE_LICENSE("GPL");
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