diff options
Diffstat (limited to 'drivers/tty/tty_ldisc.c')
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 42 |
1 files changed, 27 insertions, 15 deletions
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 1ba74d6f5e5c..03f414172f34 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -19,6 +19,7 @@ #include <linux/seq_file.h> #include <linux/uaccess.h> #include <linux/ratelimit.h> +#include "tty.h" #undef LDISC_DEBUG_HANGUP @@ -147,7 +148,7 @@ static int tty_ldisc_autoload = IS_BUILTIN(CONFIG_LDISC_AUTOLOAD); * Returns: -EINVAL if the discipline index is not [N_TTY..NR_LDISCS] or * if the discipline is not registered * -EAGAIN if request_module() failed to load or register the - * the discipline + * discipline * -ENOMEM if allocation failure * * Otherwise, returns a pointer to the discipline and bumps the @@ -459,7 +460,7 @@ static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld) WARN_ON(test_and_set_bit(TTY_LDISC_OPEN, &tty->flags)); if (ld->ops->open) { int ret; - /* BTM here locks versus a hangup event */ + /* BTM here locks versus a hangup event */ ret = ld->ops->open(tty); if (ret) clear_bit(TTY_LDISC_OPEN, &tty->flags); @@ -508,7 +509,8 @@ static int tty_ldisc_failto(struct tty_struct *tty, int ld) return PTR_ERR(disc); tty->ldisc = disc; tty_set_termios_ldisc(tty, ld); - if ((r = tty_ldisc_open(tty, disc)) < 0) + r = tty_ldisc_open(tty, disc); + if (r < 0) tty_ldisc_put(disc); return r; } @@ -529,9 +531,11 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) const char *name = tty_name(tty); pr_warn("Falling back ldisc for %s.\n", name); - /* The traditional behaviour is to fall back to N_TTY, we - want to avoid falling back to N_NULL unless we have no - choice to avoid the risk of breaking anything */ + /* + * The traditional behaviour is to fall back to N_TTY, we + * want to avoid falling back to N_NULL unless we have no + * choice to avoid the risk of breaking anything + */ if (tty_ldisc_failto(tty, N_TTY) < 0 && tty_ldisc_failto(tty, N_NULL) < 0) panic("Couldn't open N_NULL ldisc for %s.", name); @@ -600,17 +604,21 @@ int tty_set_ldisc(struct tty_struct *tty, int disc) up_read(&tty->termios_rwsem); } - /* At this point we hold a reference to the new ldisc and a - reference to the old ldisc, or we hold two references to - the old ldisc (if it was restored as part of error cleanup - above). In either case, releasing a single reference from - the old ldisc is correct. */ + /* + * At this point we hold a reference to the new ldisc and a + * reference to the old ldisc, or we hold two references to + * the old ldisc (if it was restored as part of error cleanup + * above). In either case, releasing a single reference from + * the old ldisc is correct. + */ new_ldisc = old_ldisc; out: tty_ldisc_unlock(tty); - /* Restart the work queue in case no characters kick it off. Safe if - already running */ + /* + * Restart the work queue in case no characters kick it off. Safe if + * already running + */ tty_buffer_restart_work(tty->port); err: tty_ldisc_put(new_ldisc); /* drop the extra reference */ @@ -771,6 +779,7 @@ void tty_ldisc_hangup(struct tty_struct *tty, bool reinit) int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty) { int retval = tty_ldisc_open(tty, tty->ldisc); + if (retval) return retval; @@ -811,8 +820,10 @@ void tty_ldisc_release(struct tty_struct *tty) tty_ldisc_kill(o_tty); tty_ldisc_unlock_pair(tty, o_tty); - /* And the memory resources remaining (buffers, termios) will be - disposed of when the kref hits zero */ + /* + * And the memory resources remaining (buffers, termios) will be + * disposed of when the kref hits zero + */ tty_ldisc_debug(tty, "released\n"); } @@ -829,6 +840,7 @@ EXPORT_SYMBOL_GPL(tty_ldisc_release); int tty_ldisc_init(struct tty_struct *tty) { struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY); + if (IS_ERR(ld)) return PTR_ERR(ld); tty->ldisc = ld; |