networking: make skb_put & friends return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

18 files changed, 36 insertions, 38 deletions

diff --git a/drivers/net/ethernet/allwinner/sun4i-emac.c b/drivers/net/ethernet/allwinner/sun4i-emac.c
index c8f4d26fc9d4..3143de45baaa 100644
--- a/drivers/net/ethernet/allwinner/sun4i-emac.c
+++ b/drivers/net/ethernet/allwinner/sun4i-emac.c
@@ -633,7 +633,7 @@ static void emac_rx(struct net_device *dev)
 			if (!skb)
 				continue;
 			skb_reserve(skb, 2);
-			rdptr = (u8 *) skb_put(skb, rxlen - 4);
+			rdptr = skb_put(skb, rxlen - 4);
 
 			/* Read received packet from RX SRAM */
 			if (netif_msg_rx_status(db))
diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
index 2ff6bd139c96..e1a50c87c9a9 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
@@ -471,7 +471,7 @@ static int init_tp_parity(struct adapter *adap)
 		if (!skb)
 			goto alloc_skb_fail;
 
-		req = (struct cpl_smt_write_req *)__skb_put(skb, sizeof(*req));
+		req = __skb_put(skb, sizeof(*req));
 		memset(req, 0, sizeof(*req));
 		req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 		OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, i));
@@ -495,7 +495,7 @@ static int init_tp_parity(struct adapter *adap)
 		if (!skb)
 			goto alloc_skb_fail;
 
-		req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
+		req = __skb_put(skb, sizeof(*req));
 		memset(req, 0, sizeof(*req));
 		req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 		OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, i));
@@ -518,7 +518,7 @@ static int init_tp_parity(struct adapter *adap)
 		if (!skb)
 			goto alloc_skb_fail;
 
-		req = (struct cpl_rte_write_req *)__skb_put(skb, sizeof(*req));
+		req = __skb_put(skb, sizeof(*req));
 		memset(req, 0, sizeof(*req));
 		req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 		OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_RTE_WRITE_REQ, i));
@@ -538,7 +538,7 @@ static int init_tp_parity(struct adapter *adap)
 	if (!skb)
 		goto alloc_skb_fail;
 
-	greq = (struct cpl_set_tcb_field *)__skb_put(skb, sizeof(*greq));
+	greq = __skb_put(skb, sizeof(*greq));
 	memset(greq, 0, sizeof(*greq));
 	greq->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 	OPCODE_TID(greq) = htonl(MK_OPCODE_TID(CPL_SET_TCB_FIELD, 0));
@@ -909,7 +909,7 @@ static int write_smt_entry(struct adapter *adapter, int idx)
 	if (!skb)
 		return -ENOMEM;
 
-	req = (struct cpl_smt_write_req *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, idx));
 	req->mtu_idx = NMTUS - 1;	/* should be 0 but there's a T3 bug */
@@ -952,7 +952,7 @@ static int send_pktsched_cmd(struct adapter *adap, int sched, int qidx, int lo,
 	if (!skb)
 		return -ENOMEM;
 
-	req = (struct mngt_pktsched_wr *)skb_put(skb, sizeof(*req));
+	req = skb_put(skb, sizeof(*req));
 	req->wr_hi = htonl(V_WR_OP(FW_WROPCODE_MNGT));
 	req->mngt_opcode = FW_MNGTOPCODE_PKTSCHED_SET;
 	req->sched = sched;
diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
index fa81445e334c..50cd660732c5 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
@@ -552,7 +552,7 @@ static inline void mk_tid_release(struct sk_buff *skb, unsigned int tid)
 	struct cpl_tid_release *req;
 
 	skb->priority = CPL_PRIORITY_SETUP;
-	req = (struct cpl_tid_release *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_TID_RELEASE, tid));
 }
@@ -1096,7 +1096,7 @@ static void set_l2t_ix(struct t3cdev *tdev, u32 tid, struct l2t_entry *e)
 		return;
 	}
 	skb->priority = CPL_PRIORITY_CONTROL;
-	req = (struct cpl_set_tcb_field *)skb_put(skb, sizeof(*req));
+	req = skb_put(skb, sizeof(*req));
 	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SET_TCB_FIELD, tid));
 	req->reply = 0;
diff --git a/drivers/net/ethernet/chelsio/cxgb3/l2t.c b/drivers/net/ethernet/chelsio/cxgb3/l2t.c
index 26264125865f..248e40c6966c 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/l2t.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/l2t.c
@@ -96,7 +96,7 @@ static int setup_l2e_send_pending(struct t3cdev *dev, struct sk_buff *skb,
 			return -ENOMEM;
 	}
 
-	req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	req->wr.wr_hi = htonl(V_WR_OP(FW_WROPCODE_FORWARD));
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, e->idx));
 	req->params = htonl(V_L2T_W_IDX(e->idx) | V_L2T_W_IFF(e->smt_idx) |
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
index 10736738ff30..a0fab65e80e8 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
@@ -190,7 +190,7 @@ static int del_filter_wr(struct adapter *adapter, int fidx)
 	if (!skb)
 		return -ENOMEM;
 
-	fwr = (struct fw_filter_wr *)__skb_put(skb, len);
+	fwr = __skb_put(skb, len);
 	t4_mk_filtdelwr(f->tid, fwr, adapter->sge.fw_evtq.abs_id);
 
 	/* Mark the filter as "pending" and ship off the Filter Work Request.
@@ -231,7 +231,7 @@ int set_filter_wr(struct adapter *adapter, int fidx)
 		}
 	}
 
-	fwr = (struct fw_filter_wr *)__skb_put(skb, sizeof(*fwr));
+	fwr = __skb_put(skb, sizeof(*fwr));
 	memset(fwr, 0, sizeof(*fwr));
 
 	/* It would be nice to put most of the following in t4_hw.c but most
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index 2c6de769f4e6..15fb284eafc0 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -1175,7 +1175,7 @@ static void mk_tid_release(struct sk_buff *skb, unsigned int chan,
 	struct cpl_tid_release *req;
 
 	set_wr_txq(skb, CPL_PRIORITY_SETUP, chan);
-	req = (struct cpl_tid_release *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	INIT_TP_WR(req, tid);
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_TID_RELEASE, tid));
 }
@@ -1359,7 +1359,7 @@ int cxgb4_create_server(const struct net_device *dev, unsigned int stid,
 		return -ENOMEM;
 
 	adap = netdev2adap(dev);
-	req = (struct cpl_pass_open_req *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	INIT_TP_WR(req, 0);
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_PASS_OPEN_REQ, stid));
 	req->local_port = sport;
@@ -1400,7 +1400,7 @@ int cxgb4_create_server6(const struct net_device *dev, unsigned int stid,
 		return -ENOMEM;
 
 	adap = netdev2adap(dev);
-	req = (struct cpl_pass_open_req6 *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	INIT_TP_WR(req, 0);
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_PASS_OPEN_REQ6, stid));
 	req->local_port = sport;
@@ -1432,7 +1432,7 @@ int cxgb4_remove_server(const struct net_device *dev, unsigned int stid,
 	if (!skb)
 		return -ENOMEM;
 
-	req = (struct cpl_close_listsvr_req *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	INIT_TP_WR(req, 0);
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_CLOSE_LISTSRV_REQ, stid));
 	req->reply_ctrl = htons(NO_REPLY_V(0) | (ipv6 ? LISTSVR_IPV6_V(1) :
diff --git a/drivers/net/ethernet/chelsio/cxgb4/l2t.c b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
index 6f3692db29af..f7ef8871dd0b 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/l2t.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
@@ -146,7 +146,7 @@ static int write_l2e(struct adapter *adap, struct l2t_entry *e, int sync)
 	if (!skb)
 		return -ENOMEM;
 
-	req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
+	req = __skb_put(skb, sizeof(*req));
 	INIT_TP_WR(req, 0);
 
 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ,
diff --git a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.h b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.h
index 515b94ff9080..4b5aacc09cab 100644
--- a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.h
+++ b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.h
@@ -90,7 +90,7 @@ cxgb_mk_tid_release(struct sk_buff *skb, u32 len, u32 tid, u16 chan)
 {
 	struct cpl_tid_release *req;
 
-	req = (struct cpl_tid_release *)__skb_put(skb, len);
+	req = __skb_put(skb, len);
 	memset(req, 0, len);
 
 	INIT_TP_WR(req, tid);
@@ -104,7 +104,7 @@ cxgb_mk_close_con_req(struct sk_buff *skb, u32 len, u32 tid, u16 chan,
 {
 	struct cpl_close_con_req *req;
 
-	req = (struct cpl_close_con_req *)__skb_put(skb, len);
+	req = __skb_put(skb, len);
 	memset(req, 0, len);
 
 	INIT_TP_WR(req, tid);
@@ -119,7 +119,7 @@ cxgb_mk_abort_req(struct sk_buff *skb, u32 len, u32 tid, u16 chan,
 {
 	struct cpl_abort_req *req;
 
-	req = (struct cpl_abort_req *)__skb_put(skb, len);
+	req = __skb_put(skb, len);
 	memset(req, 0, len);
 
 	INIT_TP_WR(req, tid);
@@ -134,7 +134,7 @@ cxgb_mk_abort_rpl(struct sk_buff *skb, u32 len, u32 tid, u16 chan)
 {
 	struct cpl_abort_rpl *rpl;
 
-	rpl = (struct cpl_abort_rpl *)__skb_put(skb, len);
+	rpl = __skb_put(skb, len);
 	memset(rpl, 0, len);
 
 	INIT_TP_WR(rpl, tid);
@@ -149,7 +149,7 @@ cxgb_mk_rx_data_ack(struct sk_buff *skb, u32 len, u32 tid, u16 chan,
 {
 	struct cpl_rx_data_ack *req;
 
-	req = (struct cpl_rx_data_ack *)__skb_put(skb, len);
+	req = __skb_put(skb, len);
 	memset(req, 0, len);
 
 	INIT_TP_WR(req, tid);
diff --git a/drivers/net/ethernet/davicom/dm9000.c b/drivers/net/ethernet/davicom/dm9000.c
index 008dc8161775..16fe776ddbe5 100644
--- a/drivers/net/ethernet/davicom/dm9000.c
+++ b/drivers/net/ethernet/davicom/dm9000.c
@@ -1171,7 +1171,7 @@ dm9000_rx(struct net_device *dev)
 		if (GoodPacket &&
 		    ((skb = netdev_alloc_skb(dev, RxLen + 4)) != NULL)) {
 			skb_reserve(skb, 2);
-			rdptr = (u8 *) skb_put(skb, RxLen - 4);
+			rdptr = skb_put(skb, RxLen - 4);
 
 			/* Read received packet from RX SRAM */
 
diff --git a/drivers/net/ethernet/dnet.c b/drivers/net/ethernet/dnet.c
index 3e77dd863175..5a847941c46b 100644
--- a/drivers/net/ethernet/dnet.c
+++ b/drivers/net/ethernet/dnet.c
@@ -399,7 +399,7 @@ static int dnet_poll(struct napi_struct *napi, int budget)
 			 * 'skb_put()' points to the start of sk_buff
 			 * data area.
 			 */
-			data_ptr = (unsigned int *)skb_put(skb, pkt_len);
+			data_ptr = skb_put(skb, pkt_len);
 			for (i = 0; i < (pkt_len + 3) >> 2; i++)
 				*data_ptr++ = dnet_readl(bp, RX_DATA_FIFO);
 			skb->protocol = eth_type_trans(skb, dev);
diff --git a/drivers/net/ethernet/hp/hp100.c b/drivers/net/ethernet/hp/hp100.c
index 5673b071e39d..c6164a98f257 100644
--- a/drivers/net/ethernet/hp/hp100.c
+++ b/drivers/net/ethernet/hp/hp100.c
@@ -1281,7 +1281,7 @@ static int hp100_build_rx_pdl(hp100_ring_t * ringptr,
 		 */
 		skb_reserve(ringptr->skb, 2);
 
-		ringptr->skb->data = (u_char *) skb_put(ringptr->skb, MAX_ETHER_SIZE);
+		ringptr->skb->data = skb_put(ringptr->skb, MAX_ETHER_SIZE);
 
 		/* ringptr->pdl points to the beginning of the PDL, i.e. the PDH */
 		/* Note: 1st Fragment is used for the 4 byte packet status
diff --git a/drivers/net/ethernet/intel/i40e/i40e_fcoe.c b/drivers/net/ethernet/intel/i40e/i40e_fcoe.c
index b077ef8b00fa..2d1253c5b7a1 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_fcoe.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_fcoe.c
@@ -762,7 +762,7 @@ int i40e_fcoe_handle_offload(struct i40e_ring *rx_ring,
 		    (fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA)) {
 			struct fcoe_crc_eof *crc = NULL;
 
-			crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
+			crc = skb_put(skb, sizeof(*crc));
 			crc->fcoe_eof = FC_EOF_T;
 		} else {
 			/* otherwise, drop the header only frame */
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
index 2a653ec954f5..a23c2b5411a0 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
@@ -491,7 +491,7 @@ int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
 	if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
 	    (fctl & FC_FC_END_SEQ)) {
 		skb_linearize(skb);
-		crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
+		crc = skb_put(skb, sizeof(*crc));
 		crc->fcoe_eof = FC_EOF_T;
 	}
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_selftest.c b/drivers/net/ethernet/mellanox/mlx4/en_selftest.c
index 17112faafbcc..88699b181946 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_selftest.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_selftest.c
@@ -63,8 +63,8 @@ static int mlx4_en_test_loopback_xmit(struct mlx4_en_priv *priv)
 
 	skb_reserve(skb, NET_IP_ALIGN);
 
-	ethh = (struct ethhdr *)skb_put(skb, sizeof(struct ethhdr));
-	packet	= (unsigned char *)skb_put(skb, packet_size);
+	ethh = skb_put(skb, sizeof(struct ethhdr));
+	packet = skb_put(skb, packet_size);
 	memcpy(ethh->h_dest, priv->dev->dev_addr, ETH_ALEN);
 	eth_zero_addr(ethh->h_source);
 	ethh->h_proto = htons(ETH_P_ARP);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c b/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c
index 601abf240d63..c456ca07b562 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c
@@ -136,10 +136,10 @@ static struct sk_buff *mlx5e_test_get_udp_skb(struct mlx5e_priv *priv)
 	skb_reset_mac_header(skb);
 
 	skb_set_network_header(skb, skb->len);
-	iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr));
+	iph = skb_put(skb, sizeof(struct iphdr));
 
 	skb_set_transport_header(skb, skb->len);
-	udph = (struct udphdr *)skb_put(skb, sizeof(struct udphdr));
+	udph = skb_put(skb, sizeof(struct udphdr));
 
 	/* Fill ETH header */
 	ether_addr_copy(ethh->h_dest, priv->netdev->dev_addr);
@@ -167,7 +167,7 @@ static struct sk_buff *mlx5e_test_get_udp_skb(struct mlx5e_priv *priv)
 	ip_send_check(iph);
 
 	/* Fill test header and data */
-	mlxh = (struct mlx5ehdr *)skb_put(skb, sizeof(*mlxh));
+	mlxh = skb_put(skb, sizeof(*mlxh));
 	mlxh->version = 0;
 	mlxh->magic = cpu_to_be64(MLX5E_TEST_MAGIC);
 	strlcpy(mlxh->text, mlx5e_test_text, sizeof(mlxh->text));
diff --git a/drivers/net/ethernet/micrel/ks8842.c b/drivers/net/ethernet/micrel/ks8842.c
index cb0102dd7f70..e3d7c74d47bb 100644
--- a/drivers/net/ethernet/micrel/ks8842.c
+++ b/drivers/net/ethernet/micrel/ks8842.c
@@ -669,7 +669,7 @@ static void ks8842_rx_frame(struct net_device *netdev,
 			ks8842_update_rx_counters(netdev, status, len);
 
 			if (adapter->conf_flags & KS884X_16BIT) {
-				u16 *data16 = (u16 *)skb_put(skb, len);
+				u16 *data16 = skb_put(skb, len);
 				ks8842_select_bank(adapter, 17);
 				while (len > 0) {
 					*data16++ = ioread16(adapter->hw_addr +
@@ -679,7 +679,7 @@ static void ks8842_rx_frame(struct net_device *netdev,
 					len -= sizeof(u32);
 				}
 			} else {
-				u32 *data = (u32 *)skb_put(skb, len);
+				u32 *data = skb_put(skb, len);
 
 				ks8842_select_bank(adapter, 17);
 				while (len > 0) {
diff --git a/drivers/net/ethernet/sfc/falcon/selftest.c b/drivers/net/ethernet/sfc/falcon/selftest.c
index 92bc34c91547..55c0fbbc4fb8 100644
--- a/drivers/net/ethernet/sfc/falcon/selftest.c
+++ b/drivers/net/ethernet/sfc/falcon/selftest.c
@@ -431,8 +431,7 @@ static int ef4_begin_loopback(struct ef4_tx_queue *tx_queue)
 
 		/* Copy the payload in, incrementing the source address to
 		 * exercise the rss vectors */
-		payload = ((struct ef4_loopback_payload *)
-			   skb_put(skb, sizeof(state->payload)));
+		payload = skb_put(skb, sizeof(state->payload));
 		memcpy(payload, &state->payload, sizeof(state->payload));
 		payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));
 
diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c
index dab286a337a6..f6936949fc85 100644
--- a/drivers/net/ethernet/sfc/selftest.c
+++ b/drivers/net/ethernet/sfc/selftest.c
@@ -431,8 +431,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
 
 		/* Copy the payload in, incrementing the source address to
 		 * exercise the rss vectors */
-		payload = ((struct efx_loopback_payload *)
-			   skb_put(skb, sizeof(state->payload)));
+		payload = skb_put(skb, sizeof(state->payload));
 		memcpy(payload, &state->payload, sizeof(state->payload));
 		payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));