Simplify devpts_pty_kill

[pandora-kernel.git] / fs / devpts / inode.c

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 488eb42..a70d5d0 100644 (file)
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -27,6 +27,7 @@
 #define DEVPTS_SUPER_MAGIC 0x1cd1
 
 #define DEVPTS_DEFAULT_MODE 0600
+#define PTMX_MINOR     2
 
 extern int pty_limit;                  /* Config limit on Unix98 ptys */
 static DEFINE_IDA(allocated_ptys);
@@ -169,15 +170,7 @@ static struct file_system_type devpts_fs_type = {
  * to the System V naming convention
  */
 
-static struct dentry *get_node(int num)
-{
-       char s[12];
-       struct dentry *root = devpts_root;
-       mutex_lock(&root->d_inode->i_mutex);
-       return lookup_one_len(s, root, sprintf(s, "%d", num));
-}
-
-int devpts_new_index(void)
+int devpts_new_index(struct inode *ptmx_inode)
 {
        int index;
        int ida_ret;
@@ -205,20 +198,21 @@ retry:
        return index;
 }
 
-void devpts_kill_index(int idx)
+void devpts_kill_index(struct inode *ptmx_inode, int idx)
 {
        mutex_lock(&allocated_ptys_lock);
        ida_remove(&allocated_ptys, idx);
        mutex_unlock(&allocated_ptys_lock);
 }
 
-int devpts_pty_new(struct tty_struct *tty)
+int devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty)
 {
        int number = tty->index; /* tty layer puts index from devpts_new_index() in here */
        struct tty_driver *driver = tty->driver;
        dev_t device = MKDEV(driver->major, driver->minor_start+number);
        struct dentry *dentry;
        struct inode *inode = new_inode(devpts_mnt->mnt_sb);
+       char s[12];
 
        /* We're supposed to be given the slave end of a pty */
        BUG_ON(driver->type != TTY_DRIVER_TYPE_PTY);
@@ -233,10 +227,15 @@ int devpts_pty_new(struct tty_struct *tty)
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
        init_special_inode(inode, S_IFCHR|config.mode, device);
        inode->i_private = tty;
+       tty->driver_data = inode;
 
-       dentry = get_node(number);
-       if (!IS_ERR(dentry) && !dentry->d_inode) {
-               d_instantiate(dentry, inode);
+       sprintf(s, "%d", number);
+
+       mutex_lock(&devpts_root->d_inode->i_mutex);
+
+       dentry = d_alloc_name(devpts_root, s);
+       if (!IS_ERR(dentry)) {
+               d_add(dentry, inode);
                fsnotify_create(devpts_root->d_inode, dentry);
        }
 
@@ -245,36 +244,31 @@ int devpts_pty_new(struct tty_struct *tty)
        return 0;
 }
 
-struct tty_struct *devpts_get_tty(int number)
+struct tty_struct *devpts_get_tty(struct inode *pts_inode, int number)
 {
-       struct dentry *dentry = get_node(number);
-       struct tty_struct *tty;
-
-       tty = NULL;
-       if (!IS_ERR(dentry)) {
-               if (dentry->d_inode)
-                       tty = dentry->d_inode->i_private;
-               dput(dentry);
-       }
+       BUG_ON(pts_inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
 
-       mutex_unlock(&devpts_root->d_inode->i_mutex);
-
-       return tty;
+       if (pts_inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
+               return (struct tty_struct *)pts_inode->i_private;
+       return NULL;
 }
 
-void devpts_pty_kill(int number)
+void devpts_pty_kill(struct tty_struct *tty)
 {
-       struct dentry *dentry = get_node(number);
+       struct inode *inode = tty->driver_data;
+       struct dentry *dentry;
 
-       if (!IS_ERR(dentry)) {
-               struct inode *inode = dentry->d_inode;
-               if (inode) {
-                       inode->i_nlink--;
-                       d_delete(dentry);
-                       dput(dentry);
-               }
+       BUG_ON(inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
+
+       mutex_lock(&devpts_root->d_inode->i_mutex);
+
+       dentry = d_find_alias(inode);
+       if (dentry && !IS_ERR(dentry)) {
+               inode->i_nlink--;
+               d_delete(dentry);
                dput(dentry);
        }
+
        mutex_unlock(&devpts_root->d_inode->i_mutex);
 }