RDMA/rxe: Move ICRC checking to a subroutine

Move the code in rxe_recv() that checks the ICRC on incoming packets to a
subroutine rxe_check_icrc() and move that to rxe_icrc.c.

Link: https://lore.kernel.org/r/20210707040040.15434-2-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Reviewed-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/sw/rxe/rxe_icrc.c

@@ -67,3 +67,41 @@ u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
 			rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES);
 	return crc;
 }
+
+/**
+ * rxe_icrc_check() - Compute ICRC for a packet and compare to the ICRC
+ *		      delivered in the packet.
+ * @skb: packet buffer
+ * @pkt: packet info
+ *
+ * Return: 0 if the values match else an error
+ */
+int rxe_icrc_check(struct sk_buff *skb, struct rxe_pkt_info *pkt)
+{
+	__be32 *icrcp;
+	u32 pkt_icrc;
+	u32 icrc;
+
+	icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);
+	pkt_icrc = be32_to_cpu(*icrcp);
+
+	icrc = rxe_icrc_hdr(pkt, skb);
+	icrc = rxe_crc32(pkt->rxe, icrc, (u8 *)payload_addr(pkt),
+				payload_size(pkt) + bth_pad(pkt));
+	icrc = (__force u32)cpu_to_be32(~icrc);
+
+	if (unlikely(icrc != pkt_icrc)) {
+		if (skb->protocol == htons(ETH_P_IPV6))
+			pr_warn_ratelimited("bad ICRC from %pI6c\n",
+					    &ipv6_hdr(skb)->saddr);
+		else if (skb->protocol == htons(ETH_P_IP))
+			pr_warn_ratelimited("bad ICRC from %pI4\n",
+					    &ip_hdr(skb)->saddr);
+		else
+			pr_warn_ratelimited("bad ICRC from unknown\n");
+
+		return -EINVAL;
+	}
+
+	return 0;
+}

drivers/infiniband/sw/rxe/rxe_loc.h

@@ -193,7 +193,9 @@ int rxe_completer(void *arg);
 int rxe_requester(void *arg);
 int rxe_responder(void *arg);
 
+/* rxe_icrc.c */
 u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb);
+int rxe_icrc_check(struct sk_buff *skb, struct rxe_pkt_info *pkt);
 
 void rxe_resp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb);
 

drivers/infiniband/sw/rxe/rxe_recv.c

@@ -361,8 +361,6 @@ void rxe_rcv(struct sk_buff *skb)
 	int err;
 	struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
 	struct rxe_dev *rxe = pkt->rxe;
-	__be32 *icrcp;
-	u32 calc_icrc, pack_icrc;
 
 	if (unlikely(skb->len < RXE_BTH_BYTES))
 		goto drop;
@@ -384,26 +382,9 @@ void rxe_rcv(struct sk_buff *skb)
 	if (unlikely(err))
 		goto drop;
 
-	/* Verify ICRC */
-	icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);
-	pack_icrc = be32_to_cpu(*icrcp);
-
-	calc_icrc = rxe_icrc_hdr(pkt, skb);
-	calc_icrc = rxe_crc32(rxe, calc_icrc, (u8 *)payload_addr(pkt),
-			      payload_size(pkt) + bth_pad(pkt));
-	calc_icrc = (__force u32)cpu_to_be32(~calc_icrc);
-	if (unlikely(calc_icrc != pack_icrc)) {
-		if (skb->protocol == htons(ETH_P_IPV6))
-			pr_warn_ratelimited("bad ICRC from %pI6c\n",
-					    &ipv6_hdr(skb)->saddr);
-		else if (skb->protocol == htons(ETH_P_IP))
-			pr_warn_ratelimited("bad ICRC from %pI4\n",
-					    &ip_hdr(skb)->saddr);
-		else
-			pr_warn_ratelimited("bad ICRC from unknown\n");
-
+	err = rxe_icrc_check(skb, pkt);
+	if (unlikely(err))
 		goto drop;
-	}
 
 	rxe_counter_inc(rxe, RXE_CNT_RCVD_PKTS);