[PATCH v4] scsi: qla2xxx: Fix flex array member not at end

In qla_edif_bsg.h: `struct fc_bsg_reply` and `struct fc_bsg_request`
have flexible array members, thus they must be the last member of
the parent structure. Contininging in the effort to add
`-Wflex-array-member-not-at-end`, put `struct fc_bsg_*` inside a
union with the trailing members padded to the size of `struct fc_bsg_*`
to silence the warning. This is similar to TRAILING_OVERLAP, exept
that the position of the flexible array member is also in a union,
causing it to not be the last member of the structure.

Suggested-by: John Meneghini <[email protected]>
Signed-off-by: Jesse Taube <[email protected]>
---
V1 -> V2:
 - Rewrite
V2 -> V3:
 - Fix commit description
V3 -> V4:
 - Accedentally sent V1 ;(
   Send correct version.
---
 drivers/scsi/qla2xxx/qla_edif_bsg.h | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_edif_bsg.h b/drivers/scsi/qla2xxx/qla_edif_bsg.h
index 514c265ba86e..2b32a3185629 100644
--- a/drivers/scsi/qla2xxx/qla_edif_bsg.h
+++ b/drivers/scsi/qla2xxx/qla_edif_bsg.h
@@ -36,16 +36,26 @@ struct extra_auth_els {
 } __packed;
 
 struct qla_bsg_auth_els_request {
-	struct fc_bsg_request r;
-	struct extra_auth_els e;
+	union {
+		struct fc_bsg_request r;
+		struct {
+			unsigned char __fc_bsg_request_sz[sizeof(struct fc_bsg_request)];
+			struct extra_auth_els e;
+		};
+	};
 };
 
 struct qla_bsg_auth_els_reply {
-	struct fc_bsg_reply r;
-	uint32_t rx_xchg_address;
-	uint8_t version;
-	uint8_t pad[VND_CMD_PAD_SIZE];
-	uint8_t reserved[VND_CMD_APP_RESERVED_SIZE];
+	union {
+		struct fc_bsg_reply r;
+		struct {
+			unsigned char __fc_bsg_reply_sz[sizeof(struct fc_bsg_reply)];
+			uint32_t rx_xchg_address;
+			uint8_t version;
+			uint8_t pad[VND_CMD_PAD_SIZE];
+			uint8_t reserved[VND_CMD_APP_RESERVED_SIZE];
+		};
+	};
 };
 
 struct app_id {
-- 
2.54.0