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>
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index c6e72ae..9663e87 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -1046,7 +1046,7 @@
struct inode *inode = file->f_path.dentry->d_inode;
struct vc_data *vc;
- if (file->f_op->ioctl != tty_ioctl)
+ if (file->f_op->unlocked_ioctl != tty_ioctl)
return -EINVAL;
tty = (struct tty_struct *)file->private_data;