From 73ec06fc5f5c8e1097a7a4a4ab2d7c6c3a007e81 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 13 Oct 2008 10:42:29 +0100 Subject: [PATCH] tty: Finish fixing up the init_dev interface to use ERR_PTR Original suggestion and proposal from Sukadev Bhattiprolu. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/char/pty.c | 6 +++-- drivers/char/tty_io.c | 52 +++++++++++++++++-------------------------- include/linux/tty.h | 4 ++-- 3 files changed, 27 insertions(+), 35 deletions(-) diff --git a/drivers/char/pty.c b/drivers/char/pty.c index 4e6490bda75..c9845002303 100644 --- a/drivers/char/pty.c +++ b/drivers/char/pty.c @@ -501,11 +501,13 @@ static int __ptmx_open(struct inode *inode, struct file *filp) return index; mutex_lock(&tty_mutex); - retval = tty_init_dev(ptm_driver, index, &tty, 1); + tty = tty_init_dev(ptm_driver, index, 1); mutex_unlock(&tty_mutex); - if (retval) + if (IS_ERR(tty)) { + retval = PTR_ERR(tty); goto out; + } set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ filp->private_data = tty; diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 888380f573d..b0ad4880c3a 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -1324,35 +1324,32 @@ static int tty_reopen(struct tty_struct *tty) * relaxed for the (most common) case of reopening a tty. */ -int tty_init_dev(struct tty_driver *driver, int idx, - struct tty_struct **ret_tty, int first_ok) +struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, + int first_ok) { struct tty_struct *tty, *o_tty; struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc; struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc; - int retval = 0; + int retval; /* check whether we're reopening an existing tty */ tty = tty_driver_lookup_tty(driver, idx); - if (IS_ERR(tty)) { - retval = PTR_ERR(tty); - goto end_init; - } + + if (IS_ERR(tty)) + return tty; if (tty) { retval = tty_reopen(tty); if (retval) - return retval; - *ret_tty = tty; - return 0; + return ERR_PTR(retval); + return tty; } /* Check if pty master is being opened multiple times */ if (driver->subtype == PTY_TYPE_MASTER && - (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) { - retval = -EIO; - goto end_init; - } + (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) + return ERR_PTR(-EIO); + /* * First time open is complex, especially for PTY devices. * This code guarantees that either everything succeeds and the @@ -1361,10 +1358,8 @@ int tty_init_dev(struct tty_driver *driver, int idx, * and locked termios may be retained.) */ - if (!try_module_get(driver->owner)) { - retval = -ENODEV; - goto end_init; - } + if (!try_module_get(driver->owner)) + return ERR_PTR(-ENODEV); o_tty = NULL; tp = o_tp = NULL; @@ -1475,7 +1470,8 @@ int tty_init_dev(struct tty_driver *driver, int idx, tty_driver_kref_get(driver); tty->count++; - if (tty_driver_install_tty(driver, tty) < 0) + retval = tty_driver_install_tty(driver, tty); + if (retval < 0) goto release_mem_out; /* @@ -1485,14 +1481,9 @@ int tty_init_dev(struct tty_driver *driver, int idx, */ retval = tty_ldisc_setup(tty, o_tty); - if (retval) goto release_mem_out; - - *ret_tty = tty; - /* All paths come through here to release the mutex */ -end_init: - return retval; + return tty; /* Release locally allocated memory ... nothing placed in slots */ free_mem_out: @@ -1507,8 +1498,7 @@ free_mem_out: fail_no_mem: module_put(driver->owner); - retval = -ENOMEM; - goto end_init; + return ERR_PTR(-ENOMEM); /* call the tty release_tty routine to clean out this slot */ release_mem_out: @@ -1516,7 +1506,7 @@ release_mem_out: printk(KERN_INFO "tty_init_dev: ldisc open failed, " "clearing slot %d\n", idx); release_tty(tty, idx); - goto end_init; + return ERR_PTR(retval); } void tty_free_termios(struct tty_struct *tty) @@ -1925,11 +1915,11 @@ retry_open: return -ENODEV; } got_driver: - retval = tty_init_dev(driver, index, &tty, 0); + tty = tty_init_dev(driver, index, 0); mutex_unlock(&tty_mutex); tty_driver_kref_put(driver); - if (retval) - return retval; + if (IS_ERR(tty)) + return PTR_ERR(tty); filp->private_data = tty; file_move(filp, &tty->tty_files); diff --git a/include/linux/tty.h b/include/linux/tty.h index 6cc7ccc93c6..54523a37e95 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -401,8 +401,8 @@ extern dev_t tty_devnum(struct tty_struct *tty); extern void proc_clear_tty(struct task_struct *p); extern struct tty_struct *get_current_tty(void); extern void tty_default_fops(struct file_operations *fops); -extern int tty_init_dev(struct tty_driver *driver, int idx, - struct tty_struct **ret_tty, int first_ok); +extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, + int first_ok); extern void tty_release_dev(struct file *filp); extern struct mutex tty_mutex; -- 2.41.1