tty: n_tty: use min3() in copy_from_read_buf()

n is a minimum of:
* available chars in the ring buffer
* available chars in the ring buffer till the end of the ring buffer
* requested number (*nr)

We can use min3() for that instead of two min()s.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230919085156.1578-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index e917faa0b84ce51dd31d1442fa5d85d567516f22..6a112910c05828062cc2a58393a178fe41294e31 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1965,8 +1965,7 @@ static bool copy_from_read_buf(const struct tty_struct *tty, u8 **kbp,
        size_t head = smp_load_acquire(&ldata->commit_head);
        size_t tail = MASK(ldata->read_tail);
 
-       n = min(head - ldata->read_tail, N_TTY_BUF_SIZE - tail);
-       n = min(*nr, n);
+       n = min3(head - ldata->read_tail, N_TTY_BUF_SIZE - tail, *nr);
        if (n) {
                u8 *from = read_buf_addr(ldata, tail);
                memcpy(*kbp, from, n);