[SCSI] iscsi_transport: Added Ping support

Added ping support for iscsi adapter, application can use this
interface for diagnostic network connection.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index 3aac991..7ff9678 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -60,6 +60,7 @@
 
 	ISCSI_UEVENT_PATH_UPDATE	= UEVENT_BASE + 20,
 	ISCSI_UEVENT_SET_IFACE_PARAMS	= UEVENT_BASE + 21,
+	ISCSI_UEVENT_PING		= UEVENT_BASE + 22,
 
 	/* up events */
 	ISCSI_KEVENT_RECV_PDU		= KEVENT_BASE + 1,
@@ -73,6 +74,7 @@
 	ISCSI_KEVENT_IF_DOWN		= KEVENT_BASE + 8,
 	ISCSI_KEVENT_CONN_LOGIN_STATE   = KEVENT_BASE + 9,
 	ISCSI_KEVENT_HOST_EVENT		= KEVENT_BASE + 10,
+	ISCSI_KEVENT_PING_COMP		= KEVENT_BASE + 11,
 };
 
 enum iscsi_tgt_dscvr {
@@ -186,6 +188,14 @@
 			uint32_t	host_no;
 			uint32_t	count;
 		} set_iface_params;
+		struct msg_iscsi_ping {
+			uint32_t        host_no;
+			uint32_t        iface_num;
+			uint32_t        iface_type;
+			uint32_t        payload_size;
+			uint32_t	pid;	/* unique ping id associated
+						   with each ping request */
+		} iscsi_ping;
 	} u;
 	union {
 		/* messages k -> u */
@@ -235,6 +245,13 @@
 			uint32_t	data_size;
 			enum iscsi_host_event_code code;
 		} host_event;
+		struct msg_ping_comp {
+			uint32_t        host_no;
+			uint32_t        status;
+			uint32_t	pid;	/* unique ping id associated
+						   with each ping request */
+			uint32_t        data_size;
+		} ping_comp;
 	} r;
 } __attribute__ ((aligned (sizeof(uint64_t))));