Commit f11afb61 authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

TTY: devpts, do not set driver_data 



The goal is to stop setting and using tty->driver_data in devpts code.
It should be used solely by the driver's code, pty in this case.

Now driver_data are managed only in the pty driver. devpts_pty_new is
switched to accept what we used to dig out of tty_struct, i.e. device
node number and index.

This also removes a note about driver_data being set outside of the
driver.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Acked-by: default avatarAlan Cox <alan@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 162b97cf

drivers/tty/pty.c

+5 −5
Original line number Diff line number Diff line
@@ -4,9 +4,6 @@ 
 *  Added support for a Unix98-style ptmx device.

 *    -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998

 *

 *  When reading this code see also fs/devpts. In particular note that the

 *  driver_data field is used by the devpts side as a binding to the devpts

 *  inode.

 */



#include <linux/module.h>
@@ -59,7 +56,7 @@ static void pty_close(struct tty_struct *tty, struct file *filp) 
#ifdef CONFIG_UNIX98_PTYS

		if (tty->driver == ptm_driver) {

		        mutex_lock(&devpts_mutex);

			devpts_pty_kill(tty->link);

			devpts_pty_kill(tty->link->driver_data);

		        mutex_unlock(&devpts_mutex);

		}

#endif
@@ -651,7 +648,9 @@ static int ptmx_open(struct inode *inode, struct file *filp) 


	tty_add_file(tty, filp);



	slave_inode = devpts_pty_new(inode, tty->link);

	slave_inode = devpts_pty_new(inode,

			MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index,

			tty->link);

	if (IS_ERR(slave_inode)) {

		retval = PTR_ERR(slave_inode);

		goto err_release;
@@ -662,6 +661,7 @@ static int ptmx_open(struct inode *inode, struct file *filp) 
		goto err_release;



	tty_unlock(tty);

	tty->link->driver_data = slave_inode;

	return 0;

err_release:

	tty_unlock(tty);

fs/devpts/inode.c

+6 −15
Original line number Diff line number Diff line
@@ -545,12 +545,9 @@ void devpts_kill_index(struct inode *ptmx_inode, int idx) 
	mutex_unlock(&allocated_ptys_lock);

}



struct inode *devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty)

struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index,

		void *priv)

{

	/* tty layer puts index from devpts_new_index() in here */

	int number = tty->index;

	struct tty_driver *driver = tty->driver;

	dev_t device = MKDEV(driver->major, driver->minor_start+number);

	struct dentry *dentry;

	struct super_block *sb = pts_sb_from_inode(ptmx_inode);

	struct inode *inode;
@@ -559,23 +556,18 @@ struct inode *devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty) 
	struct pts_mount_opts *opts = &fsi->mount_opts;

	char s[12];



	/* We're supposed to be given the slave end of a pty */

	BUG_ON(driver->type != TTY_DRIVER_TYPE_PTY);

	BUG_ON(driver->subtype != PTY_TYPE_SLAVE);



	inode = new_inode(sb);

	if (!inode)

		return ERR_PTR(-ENOMEM);



	inode->i_ino = number + 3;

	inode->i_ino = index + 3;

	inode->i_uid = opts->setuid ? opts->uid : current_fsuid();

	inode->i_gid = opts->setgid ? opts->gid : current_fsgid();

	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;

	init_special_inode(inode, S_IFCHR|opts->mode, device);

	inode->i_private = tty;

	tty->driver_data = inode;

	inode->i_private = priv;



	sprintf(s, "%d", number);

	sprintf(s, "%d", index);



	mutex_lock(&root->d_inode->i_mutex);
@@ -613,9 +605,8 @@ void *devpts_get_priv(struct inode *pts_inode) 
	return priv;

}



void devpts_pty_kill(struct tty_struct *tty)

void devpts_pty_kill(struct inode *inode)

{

	struct inode *inode = tty->driver_data;

	struct super_block *sb = pts_sb_from_inode(inode);

	struct dentry *root = sb->s_root;

	struct dentry *dentry;

include/linux/devpts_fs.h

+5 −4
Original line number Diff line number Diff line
@@ -20,11 +20,12 @@ 
int devpts_new_index(struct inode *ptmx_inode);

void devpts_kill_index(struct inode *ptmx_inode, int idx);

/* mknod in devpts */

struct inode *devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty);

struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index,

		void *priv);

/* get private structure */

void *devpts_get_priv(struct inode *pts_inode);

/* unlink */

void devpts_pty_kill(struct tty_struct *tty);

void devpts_pty_kill(struct inode *inode);



#else
@@ -32,7 +33,7 @@ void devpts_pty_kill(struct tty_struct *tty); 
static inline int devpts_new_index(struct inode *ptmx_inode) { return -EINVAL; }

static inline void devpts_kill_index(struct inode *ptmx_inode, int idx) { }

static inline struct inode *devpts_pty_new(struct inode *ptmx_inode,

		struct tty_struct *tty)

		dev_t device, int index, void *priv)

{

	return ERR_PTR(-EINVAL);

}
@@ -40,7 +41,7 @@ static inline void *devpts_get_priv(struct inode *pts_inode) 
{

	return NULL;

}

static inline void devpts_pty_kill(struct tty_struct *tty) { }

static inline void devpts_pty_kill(struct inode *inode) { }



#endif

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