diff options
author | Alan Cox <alan@lxorguk.ukuu.org.uk> | 2008-04-30 00:53:29 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-30 08:29:40 -0700 |
commit | 04f378b198da233ca0aca341b113dc6579d46123 (patch) | |
tree | 696e7bd401125cee71ecaa2047c4273f38732554 /drivers/char/vt.c | |
parent | e52384426064bca0669a954736206adca7595d48 (diff) | |
download | lwn-04f378b198da233ca0aca341b113dc6579d46123.tar.gz lwn-04f378b198da233ca0aca341b113dc6579d46123.zip |
tty: BKL pushdown
- Push the BKL down into the line disciplines
- Switch the tty layer to unlocked_ioctl
- Introduce a new ctrl_lock spin lock for the control bits
- Eliminate much of the lock_kernel use in n_tty
- Prepare to (but don't yet) call the drivers with the lock dropped
on the paths that historically held the lock
BKL now primarily protects open/close/ldisc change in the tty layer
[jirislaby@gmail.com: a couple of fixes]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/char/vt.c')
-rw-r--r-- | drivers/char/vt.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/char/vt.c b/drivers/char/vt.c index 1c2660477135..e64f0bf3624e 100644 --- a/drivers/char/vt.c +++ b/drivers/char/vt.c @@ -2541,6 +2541,9 @@ int tioclinux(struct tty_struct *tty, unsigned long arg) if (get_user(type, p)) return -EFAULT; ret = 0; + + lock_kernel(); + switch (type) { case TIOCL_SETSEL: @@ -2560,7 +2563,7 @@ int tioclinux(struct tty_struct *tty, unsigned long arg) ret = sel_loadlut(p); break; case TIOCL_GETSHIFTSTATE: - + /* * Make it possible to react to Shift+Mousebutton. * Note that 'shift_state' is an undocumented @@ -2615,6 +2618,7 @@ int tioclinux(struct tty_struct *tty, unsigned long arg) ret = -EINVAL; break; } + unlock_kernel(); return ret; } @@ -3829,7 +3833,7 @@ static int con_font_get(struct vc_data *vc, struct console_font_op *op) goto out; c = (font.width+7)/8 * 32 * font.charcount; - + if (op->data && font.charcount > op->charcount) rc = -ENOSPC; if (!(op->flags & KD_FONT_FLAG_OLD)) { |