tty: fix up hung_up_tty_write() conversion

In commit "tty: implement write_iter", I left the write_iter conversion
of the hung up tty case alone, because I incorrectly thought it didn't
matter.

Jiri showed me the errors of my ways, and pointed out the problems with
that incomplete conversion.  Fix it all up.

Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/CAHk-=wh+-rGsa=xruEWdg_fJViFG8rN9bpLrfLz=_yBYh2tBhA@mail.gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 5028626..4a208a9 100644 (file)
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -437,8 +437,7 @@ static ssize_t hung_up_tty_read(struct file *file, char __user *buf,
        return 0;
 }
 
-static ssize_t hung_up_tty_write(struct file *file, const char __user *buf,
-                                size_t count, loff_t *ppos)
+static ssize_t hung_up_tty_write(struct kiocb *iocb, struct iov_iter *from)
 {
        return -EIO;
 }
@@ -504,7 +503,7 @@ static const struct file_operations console_fops = {
 static const struct file_operations hung_up_tty_fops = {
        .llseek         = no_llseek,
        .read           = hung_up_tty_read,
-       .write          = hung_up_tty_write,
+       .write_iter     = hung_up_tty_write,
        .poll           = hung_up_tty_poll,
        .unlocked_ioctl = hung_up_tty_ioctl,
        .compat_ioctl   = hung_up_tty_compat_ioctl,
@@ -1044,7 +1043,9 @@ static ssize_t tty_write(struct kiocb *iocb, struct iov_iter *from)
        if (tty->ops->write_room == NULL)
                tty_err(tty, "missing write_room method\n");
        ld = tty_ldisc_ref_wait(tty);
-       if (!ld || !ld->ops->write)
+       if (!ld)
+               return hung_up_tty_write(iocb, from);
+       if (!ld->ops->write)
                ret = -EIO;
        else
                ret = do_tty_write(ld->ops->write, tty, file, from);