kernel_optimize_test/drivers/net/slip
Al Viro f0193d3ea7 change semantics of ldisc ->compat_ioctl()
First of all, make it return int.  Returning long when native method
had never allowed that is ridiculous and inconvenient.

More importantly, change the caller; if ldisc ->compat_ioctl() is NULL
or returns -ENOIOCTLCMD, tty_compat_ioctl() will try to feed cmd and
compat_ptr(arg) to ldisc's native ->ioctl().

That simplifies ->compat_ioctl() instances quite a bit - they only
need to deal with ioctls that are neither generic tty ones (those
would get shunted off to tty_ioctl()) nor simple compat pointer ones.

Note that something like TCFLSH won't reach ->compat_ioctl(),
even if ldisc ->ioctl() does handle it - it will be recognized
earlier and passed to tty_ioctl() (and ultimately - ldisc ->ioctl()).

For many ldiscs it means that NULL ->compat_ioctl() does the
right thing.  Those where it won't serve (see e.g. n_r3964.c) are
also easily dealt with - we need to handle the numeric-argument
ioctls (calling the native instance) and, if such would exist,
the ioctls that need layout conversion, etc.

All in-tree ldiscs dealt with.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:53 -04:00
..
Kconfig tty: Added a CONFIG_TTY option to allow removal of TTY 2013-01-18 16:15:27 -08:00
Makefile
slhc.c slip: Check if rstate is initialized before uncompressing 2018-04-11 10:33:46 -04:00
slip.c change semantics of ldisc ->compat_ioctl() 2018-10-13 00:50:53 -04:00
slip.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00