proc tty: add struct tty_operations::proc_fops

Used for gradual switch of TTY drivers from using ->read_proc which helps
with gradual switch from ->read_proc for the whole tree.

As side effect, fix possible race condition when ->data initialized after
PDE is hooked into proc tree.

->proc_fops takes precedence over ->read_proc.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alexey Dobriyan 2009-03-31 15:19:15 -07:00 committed by Linus Torvalds
parent 15f7176eb1
commit ae149b6bec
2 changed files with 14 additions and 7 deletions

View file

@ -144,16 +144,22 @@ void proc_tty_register_driver(struct tty_driver *driver)
{
struct proc_dir_entry *ent;
if (!driver->ops->read_proc || !driver->driver_name ||
driver->proc_entry)
if (!driver->driver_name || driver->proc_entry)
return;
ent = create_proc_entry(driver->driver_name, 0, proc_tty_driver);
if (!ent)
if (driver->ops->proc_fops) {
ent = proc_create_data(driver->driver_name, 0, proc_tty_driver,
driver->ops->proc_fops, driver);
if (!ent)
return;
} else if (driver->ops->read_proc) {
ent = create_proc_entry(driver->driver_name, 0, proc_tty_driver);
if (!ent)
return;
ent->read_proc = driver->ops->read_proc;
ent->data = driver;
} else
return;
ent->read_proc = driver->ops->read_proc;
ent->data = driver;
driver->proc_entry = ent;
}

View file

@ -264,6 +264,7 @@ struct tty_operations {
int (*poll_get_char)(struct tty_driver *driver, int line);
void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
#endif
const struct file_operations *proc_fops;
};
struct tty_driver {