Simplify devpts_pty_kill

When creating a new pty, save the pty's inode in the tty->driver_data.
Use this inode in pty_kill() to identify the devpts instance. Since
we now have the inode for the pty, we can skip get_node() lookup and
remove the unused get_node().

TODO:
	- check if the mutex_lock is needed in pty_kill().

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sukadev Bhattiprolu 2008-10-13 10:43:27 +01:00 committed by Linus Torvalds
parent 89a52e109e
commit a6f37daa8b

View file

@ -170,14 +170,6 @@ 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(struct inode *ptmx_inode)
{
int index;
@ -235,6 +227,7 @@ int devpts_pty_new(struct inode *ptmx_inode, 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;
sprintf(s, "%d", number);
@ -262,18 +255,20 @@ struct tty_struct *devpts_get_tty(struct inode *pts_inode, int number)
void devpts_pty_kill(struct tty_struct *tty)
{
int number = tty->index;
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);
}