From f0193d3ea73b966b5dbfa272c8228d743b8856ef Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 13 Sep 2018 22:12:15 -0400 Subject: 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 --- net/nfc/nci/uart.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/nfc') diff --git a/net/nfc/nci/uart.c b/net/nfc/nci/uart.c index a66f102c6c01..d1fa0f22c10c 100644 --- a/net/nfc/nci/uart.c +++ b/net/nfc/nci/uart.c @@ -465,6 +465,7 @@ static struct tty_ldisc_ops nci_uart_ldisc = { .receive_buf = nci_uart_tty_receive, .write_wakeup = nci_uart_tty_wakeup, .ioctl = nci_uart_tty_ioctl, + .compat_ioctl = nci_uart_tty_ioctl, }; static int __init nci_uart_init(void) -- cgit v1.2.3-59-g8ed1b