[SCSI] bnx2fc: Allocate fcoe_ctlr with bnx2fc_interface, not as a member

    Currently the fcoe_ctlr associated with an interface is allocated
    as a member of struct bnx2fc_interface. This causes problems when
    when later patches attempt to use the new fcoe_sysfs APIs which
    allow us to allocate the bnx2fc_interface as private data to a
    fcoe_ctlr_device instance. The problem is that libfcoe wants to
    be able use pointer math to find a fcoe_ctlr's fcoe_ctlr_device
    as well as finding a fcoe_ctlr_device's assocated fcoe_ctlr. To
    do this we need to allocate the fcoe_ctlr_device, with private
    data for the LLD. The private data will contain the fcoe_ctlr
    and its private data will be the bnx2fc_interface.

    +-------------------+
    | fcoe_ctlr_device  |
    +-------------------+
    | fcoe_ctlr         |
    +-------------------+
    | bnx2fc_interface  |
    +-------------------+

    This prep work will allow us to go from a fcoe_ctlr_device
    instance to its fcoe_ctlr as well as from a fcoe_ctlr to its
    fcoe_ctlr_device once the fcoe_sysfs API is in use (later
    patches in this series).

Signed-off-by: Robert Love <robert.w.love@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/bnx2fc/bnx2fc.h

@@ -228,13 +228,16 @@ struct bnx2fc_interface {
 	struct packet_type fip_packet_type;
 	struct workqueue_struct *timer_work_queue;
 	struct kref kref;
-	struct fcoe_ctlr ctlr;
 	u8 vlan_enabled;
 	int vlan_id;
 	bool enabled;
 };
 
-#define bnx2fc_from_ctlr(fip) container_of(fip, struct bnx2fc_interface, ctlr)
+#define bnx2fc_from_ctlr(x)			\
+	((struct bnx2fc_interface *)((x) + 1))
+
+#define bnx2fc_to_ctlr(x)					\
+	((struct fcoe_ctlr *)(((struct fcoe_ctlr *)(x)) - 1))
 
 struct bnx2fc_lport {
 	struct list_head list;

drivers/scsi/bnx2fc/bnx2fc_els.c

@@ -900,7 +900,7 @@ struct fc_seq *bnx2fc_elsct_send(struct fc_lport *lport, u32 did,
 {
 	struct fcoe_port *port = lport_priv(lport);
 	struct bnx2fc_interface *interface = port->priv;
-	struct fcoe_ctlr *fip = &interface->ctlr;
+	struct fcoe_ctlr *fip = bnx2fc_to_ctlr(interface);
 	struct fc_frame_header *fh = fc_frame_header_get(fp);
 
 	switch (op) {