net: remove noblock parameter from skb_recv_datagram()

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/mISDN/socket.c

@@ -121,7 +121,7 @@ mISDN_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	if (sk->sk_state == MISDN_CLOSED)
 		return 0;
 
-	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		return err;
 

drivers/net/ppp/pppoe.c

@@ -1011,8 +1011,7 @@ static int pppoe_recvmsg(struct socket *sock, struct msghdr *m,
 		goto end;
 	}
 
-	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
-				flags & MSG_DONTWAIT, &error);
+	skb = skb_recv_datagram(sk, flags, &error);
 	if (error < 0)
 		goto end;
 

include/linux/skbuff.h

@@ -3836,8 +3836,7 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk,
 struct sk_buff *__skb_recv_datagram(struct sock *sk,
 				    struct sk_buff_head *sk_queue,
 				    unsigned int flags, int *off, int *err);
-struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock,
-				  int *err);
+struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned int flags, int *err);
 __poll_t datagram_poll(struct file *file, struct socket *sock,
 			   struct poll_table_struct *wait);
 int skb_copy_datagram_iter(const struct sk_buff *from, int offset,

net/appletalk/ddp.c

@@ -1753,8 +1753,7 @@ static int atalk_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	int err = 0;
 	struct sk_buff *skb;
 
-	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
-						flags & MSG_DONTWAIT, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	lock_sock(sk);
 
 	if (!skb)

net/atm/common.c

@@ -540,7 +540,7 @@ int vcc_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	    !test_bit(ATM_VF_READY, &vcc->flags))
 		return 0;
 
-	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &error);
+	skb = skb_recv_datagram(sk, flags, &error);
 	if (!skb)
 		return error;
 

net/ax25/af_ax25.c

@@ -1669,8 +1669,7 @@ static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	}
 
 	/* Now we can treat all alike */
-	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
-				flags & MSG_DONTWAIT, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (skb == NULL)
 		goto out;
 

net/bluetooth/af_bluetooth.c

@@ -251,7 +251,6 @@ EXPORT_SYMBOL(bt_accept_dequeue);
 int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 		    int flags)
 {
-	int noblock = flags & MSG_DONTWAIT;
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	size_t copied;
@@ -263,7 +262,7 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	if (flags & MSG_OOB)
 		return -EOPNOTSUPP;
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb) {
 		if (sk->sk_shutdown & RCV_SHUTDOWN)
 			return 0;

net/bluetooth/hci_sock.c

@@ -1453,7 +1453,6 @@ static void hci_sock_cmsg(struct sock *sk, struct msghdr *msg,
 static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg,
 			    size_t len, int flags)
 {
-	int noblock = flags & MSG_DONTWAIT;
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	int copied, err;
@@ -1470,7 +1469,7 @@ static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg,
 	if (sk->sk_state == BT_CLOSED)
 		return 0;
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		return err;
 

net/caif/caif_socket.c

@@ -282,7 +282,7 @@ static int caif_seqpkt_recvmsg(struct socket *sock, struct msghdr *m,
 	if (flags & MSG_OOB)
 		goto read_error;
 
-	skb = skb_recv_datagram(sk, flags, 0 , &ret);
+	skb = skb_recv_datagram(sk, flags, &ret);
 	if (!skb)
 		goto read_error;
 	copylen = skb->len;

net/can/bcm.c

@@ -1632,12 +1632,9 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	int error = 0;
-	int noblock;
 	int err;
 
-	noblock =  flags & MSG_DONTWAIT;
-	flags   &= ~MSG_DONTWAIT;
-	skb = skb_recv_datagram(sk, flags, noblock, &error);
+	skb = skb_recv_datagram(sk, flags, &error);
 	if (!skb)
 		return error;
 

net/can/isotp.c

@@ -1047,7 +1047,6 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	struct isotp_sock *so = isotp_sk(sk);
-	int noblock = flags & MSG_DONTWAIT;
 	int ret = 0;
 
 	if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
@@ -1056,8 +1055,7 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	if (!so->bound)
 		return -EADDRNOTAVAIL;
 
-	flags &= ~MSG_DONTWAIT;
-	skb = skb_recv_datagram(sk, flags, noblock, &ret);
+	skb = skb_recv_datagram(sk, flags, &ret);
 	if (!skb)
 		return ret;
 

net/can/j1939/socket.c

@@ -802,7 +802,7 @@ static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg,
 		return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939,
 					  SCM_J1939_ERRQUEUE);
 
-	skb = skb_recv_datagram(sk, flags, 0, &ret);
+	skb = skb_recv_datagram(sk, flags, &ret);
 	if (!skb)
 		return ret;
 

net/can/raw.c

@@ -846,16 +846,12 @@ static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	struct sock *sk = sock->sk;
 	struct sk_buff *skb;
 	int err = 0;
-	int noblock;
-
-	noblock = flags & MSG_DONTWAIT;
-	flags &= ~MSG_DONTWAIT;
 
 	if (flags & MSG_ERRQUEUE)
 		return sock_recv_errqueue(sk, msg, size,
 					  SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE);
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		return err;
 

net/core/datagram.c

@@ -310,12 +310,11 @@ struct sk_buff *__skb_recv_datagram(struct sock *sk,
 EXPORT_SYMBOL(__skb_recv_datagram);
 
 struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned int flags,
-				  int noblock, int *err)
+				  int *err)
 {
 	int off = 0;
 
-	return __skb_recv_datagram(sk, &sk->sk_receive_queue,
-				   flags | (noblock ? MSG_DONTWAIT : 0),
+	return __skb_recv_datagram(sk, &sk->sk_receive_queue, flags,
 				   &off, err);
 }
 EXPORT_SYMBOL(skb_recv_datagram);

net/ieee802154/socket.c

@@ -314,7 +314,8 @@ static int raw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	int err = -EOPNOTSUPP;
 	struct sk_buff *skb;
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	flags |= (noblock ? MSG_DONTWAIT : 0);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		goto out;
 
@@ -703,7 +704,8 @@ static int dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	struct dgram_sock *ro = dgram_sk(sk);
 	DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	flags |= (noblock ? MSG_DONTWAIT : 0);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		goto out;
 

net/ipv4/ping.c

@@ -861,7 +861,8 @@ int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 	if (flags & MSG_ERRQUEUE)
 		return inet_recv_error(sk, msg, len, addr_len);
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	flags |= (noblock ? MSG_DONTWAIT : 0);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		goto out;
 

net/ipv4/raw.c

@@ -769,7 +769,8 @@ static int raw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 		goto out;
 	}
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	flags |= (noblock ? MSG_DONTWAIT : 0);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		goto out;
 

net/ipv6/raw.c

@@ -477,7 +477,8 @@ static int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
 		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	flags |= (noblock ? MSG_DONTWAIT : 0);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb)
 		goto out;
 

net/iucv/af_iucv.c

@@ -1223,7 +1223,6 @@ static void iucv_process_message_q(struct sock *sk)
 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
 			     size_t len, int flags)
 {
-	int noblock = flags & MSG_DONTWAIT;
 	struct sock *sk = sock->sk;
 	struct iucv_sock *iucv = iucv_sk(sk);
 	unsigned int copied, rlen;
@@ -1242,7 +1241,7 @@ static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
 
 	/* receive/dequeue next skb:
 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
-	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb) {
 		if (sk->sk_shutdown & RCV_SHUTDOWN)
 			return 0;

net/key/af_key.c

@@ -3696,7 +3696,7 @@ static int pfkey_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
 		goto out;
 
-	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
+	skb = skb_recv_datagram(sk, flags, &err);
 	if (skb == NULL)
 		goto out;