net/smc: unify the structs of accept or confirm message for v1 and v2

The structs of CLC accept and confirm messages for SMCv1 and SMCv2 are
separately defined and often casted to each other in the code, which may
increase the risk of errors caused by future divergence of them. So
unify them into one struct for better maintainability.

Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 25 deletions

diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h
index 1697b84d85be..03f9ccea8c5e 100644
--- a/net/smc/smc_clc.h
+++ b/net/smc/smc_clc.h
@@ -259,28 +259,21 @@ struct smc_clc_fce_gid_ext {
 struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
 	struct smc_clc_msg_hdr hdr;
 	union {
-		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
-		struct { /* SMC-D */
-			struct smcd_clc_msg_accept_confirm_common d0;
-			u32 reserved5[3];
-		};
-	};
-} __packed;			/* format defined in RFC7609 */
-
-struct smc_clc_msg_accept_confirm_v2 {	/* clc accept / confirm message */
-	struct smc_clc_msg_hdr hdr;
-	union {
 		struct { /* SMC-R */
 			struct smcr_clc_msg_accept_confirm r0;
-			u8 eid[SMC_MAX_EID_LEN];
-			u8 reserved6[8];
-		} r1;
+			struct { /* v2 only */
+				u8 eid[SMC_MAX_EID_LEN];
+				u8 reserved6[8];
+			} __packed r1;
+		};
 		struct { /* SMC-D */
 			struct smcd_clc_msg_accept_confirm_common d0;
-			__be16 chid;
-			u8 eid[SMC_MAX_EID_LEN];
-			u8 reserved5[8];
-		} d1;
+			struct { /* v2 only, but 12 bytes reserved in v1 */
+				__be16 chid;
+				u8 eid[SMC_MAX_EID_LEN];
+				u8 reserved5[8];
+			} __packed d1;
+		};
 	};
 };
 
@@ -389,24 +382,23 @@ smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
 }
 
 static inline struct smc_clc_first_contact_ext *
-smc_get_clc_first_contact_ext(struct smc_clc_msg_accept_confirm_v2 *clc_v2,
+smc_get_clc_first_contact_ext(struct smc_clc_msg_accept_confirm *clc,
 			      bool is_smcd)
 {
 	int clc_v2_len;
 
-	if (clc_v2->hdr.version == SMC_V1 ||
-	    !(clc_v2->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
+	if (clc->hdr.version == SMC_V1 ||
+	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
 		return NULL;
 
 	if (is_smcd)
 		clc_v2_len =
-			offsetofend(struct smc_clc_msg_accept_confirm_v2, d1);
+			offsetofend(struct smc_clc_msg_accept_confirm, d1);
 	else
 		clc_v2_len =
-			offsetofend(struct smc_clc_msg_accept_confirm_v2, r1);
+			offsetofend(struct smc_clc_msg_accept_confirm, r1);
 
-	return (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) +
-						    clc_v2_len);
+	return (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
 }
 
 struct smcd_dev;