On 21. 01. 21, 10:00, Greg Kroah-Hartman wrote:
From: Linus Torvalds <torva...@linux-foundation.org>
Now that the ldisc read() function takes kernel pointers, it's fairly
straightforward to make the tty file operations use .read_iter() instead
of .read().
That automatically gives us vread() and friends, and also makes it
possible to do .splice_read() on ttys again.
Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops")
Reported-by: Oliver Giles <ohw.gi...@gmail.com>
Cc: Christoph Hellwig <h...@lst.de>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Al Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torva...@linux-foundation.org>
---
drivers/tty/tty_io.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index a34f8bcf875e..8846d3b99845 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
...
@@ -907,10 +909,10 @@ static int iterate_tty_read(struct tty_ldisc *ld, struct
tty_struct *tty, struct
* read calls may be outstanding in parallel.
*/
-static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
- loff_t *ppos)
+static ssize_t tty_read(struct kiocb *iocb, struct iov_iter *to)
{
int i;
+ struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
struct tty_struct *tty = file_tty(file);
struct tty_ldisc *ld;
@@ -923,11 +925,9 @@ static ssize_t tty_read(struct file *file, char __user
*buf, size_t count,
/* We want to wait for the line discipline to sort out in this
situation */
ld = tty_ldisc_ref_wait(tty);
- if (!ld)
- return hung_up_tty_read(file, buf, count, ppos);
i = -EIO;
- if (ld->ops->read)
- i = iterate_tty_read(ld, tty, file, buf, count);
+ if (ld && ld->ops->read)
+ i = iterate_tty_read(ld, tty, file, to);
tty_ldisc_deref(ld);
Here we have the same problem as in tty_write.
And also the other one with hung_up_tty_read not converted.
thanks,
--
js
