[SCSI] libfc: release DDP context if frame_send() fails

In case frame_send() fails, make sure to let the underlying HW release the DDP
context that has already been set up before calling frame_send().

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>

drivers/scsi/libfc/fc_exch.c

@@ -1978,6 +1978,7 @@ static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
 	spin_unlock_bh(&ep->ex_lock);
 	return sp;
 err:
+	fc_fcp_ddp_done(fr_fsp(fp));
 	rc = fc_exch_done_locked(ep);
 	spin_unlock_bh(&ep->ex_lock);
 	if (!rc)

drivers/scsi/libfc/fc_fcp.c

@@ -312,7 +312,7 @@ void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
  *		       DDP related resources for a fcp_pkt
  * @fsp: The FCP packet that DDP had been used on
  */
-static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
+void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
 {
 	struct fc_lport *lport;
 

drivers/scsi/libfc/fc_libfc.h

@@ -108,6 +108,7 @@ extern struct fc4_prov fc_rport_fcp_init;	/* FCP initiator provider */
  * Set up direct-data placement for this I/O request
  */
 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid);
+void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp);
 
 /*
  * Module setup functions