[PATCH net-next RESEND 2/2] af_unix: Refactor unix_read_skb()

From: Peilin Ye
Date: Fri Sep 23 2022 - 00:59:51 EST


From: Peilin Ye <peilin.ye@xxxxxxxxxxxxx>

Similar to udp_read_skb(), delete the unnecessary while loop in
unix_read_skb() for readability. Since recv_actor() cannot return a
value greater than skb->len (see sk_psock_verdict_recv()), remove the
redundant check.

Suggested-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
Signed-off-by: Peilin Ye <peilin.ye@xxxxxxxxxxxxx>
---
net/unix/af_unix.c | 34 ++++++++++------------------------
1 file changed, 10 insertions(+), 24 deletions(-)

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index dea2972c8178..c955c7253d4b 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -2536,32 +2536,18 @@ static int unix_dgram_recvmsg(struct socket *sock, struct msghdr *msg, size_t si

static int unix_read_skb(struct sock *sk, skb_read_actor_t recv_actor)
{
- int copied = 0;
-
- while (1) {
- struct unix_sock *u = unix_sk(sk);
- struct sk_buff *skb;
- int used, err;
-
- mutex_lock(&u->iolock);
- skb = skb_recv_datagram(sk, MSG_DONTWAIT, &err);
- mutex_unlock(&u->iolock);
- if (!skb)
- return err;
+ struct unix_sock *u = unix_sk(sk);
+ struct sk_buff *skb;
+ int err, copied;

- used = recv_actor(sk, skb);
- if (used <= 0) {
- if (!copied)
- copied = used;
- kfree_skb(skb);
- break;
- } else if (used <= skb->len) {
- copied += used;
- }
+ mutex_lock(&u->iolock);
+ skb = skb_recv_datagram(sk, MSG_DONTWAIT, &err);
+ mutex_unlock(&u->iolock);
+ if (!skb)
+ return err;

- kfree_skb(skb);
- break;
- }
+ copied = recv_actor(sk, skb);
+ kfree_skb(skb);

return copied;
}
--
2.20.1