MFC r268326:

Make iSCSI initiator keep Initiator Session ID (ISID) across reconnects.

Previously ISID was changed every time, that made impossible correct
persistent reservation, because reconnected session was identified as
completely new one.

3 files changed, 13 insertions, 6 deletions

diff --git a/sys/dev/iscsi/iscsi.c b/sys/dev/iscsi/iscsi.c
index e7691fc..0a75838 100644
--- a/sys/dev/iscsi/iscsi.c
+++ b/sys/dev/iscsi/iscsi.c
@@ -1226,6 +1226,9 @@ iscsi_ioctl_daemon_wait(struct iscsi_softc *sc,
 		ISCSI_SESSION_UNLOCK(is);
 
 		request->idr_session_id = is->is_id;
+		memcpy(&request->idr_isid, &is->is_isid,
+		    sizeof(request->idr_isid));
+		request->idr_tsih = 0;	/* New or reinstated session. */
 		memcpy(&request->idr_conf, &is->is_conf,
 		    sizeof(request->idr_conf));
 
@@ -1275,7 +1278,7 @@ iscsi_ioctl_daemon_handoff(struct iscsi_softc *sc,
 
 	strlcpy(is->is_target_alias, handoff->idh_target_alias,
 	    sizeof(is->is_target_alias));
-	memcpy(is->is_isid, handoff->idh_isid, sizeof(is->is_isid));
+	is->is_tsih = handoff->idh_tsih;
 	is->is_statsn = handoff->idh_statsn;
 	is->is_initial_r2t = handoff->idh_initial_r2t;
 	is->is_immediate_data = handoff->idh_immediate_data;
@@ -1651,6 +1654,9 @@ iscsi_ioctl_session_add(struct iscsi_softc *sc, struct iscsi_session_add *isa)
 	is->is_softc = sc;
 	sc->sc_last_session_id++;
 	is->is_id = sc->sc_last_session_id;
+	is->is_isid[0] = 0x80; /* RFC 3720, 10.12.5: 10b, "Random" ISID. */
+	arc4rand(&is->is_isid[1], 5, 0);
+	is->is_tsih = 0;
 	callout_init(&is->is_callout, 1);
 	callout_reset(&is->is_callout, 1 * hz, iscsi_callout, is);
 	TAILQ_INSERT_TAIL(&sc->sc_sessions, is, is_next);
diff --git a/sys/dev/iscsi/iscsi.h b/sys/dev/iscsi/iscsi.h
index e18f7f8..0fe1515 100644
--- a/sys/dev/iscsi/iscsi.h
+++ b/sys/dev/iscsi/iscsi.h
@@ -64,6 +64,7 @@ struct iscsi_session {
 	size_t				is_max_burst_length;
 	size_t				is_first_burst_length;
 	uint8_t				is_isid[6];
+	uint16_t			is_tsih;
 	bool				is_immediate_data;
 	size_t				is_max_data_segment_length;
 	char				is_target_alias[ISCSI_ALIAS_LEN];
diff --git a/sys/dev/iscsi/iscsi_ioctl.h b/sys/dev/iscsi/iscsi_ioctl.h
index ace1ebd..4e06b87 100644
--- a/sys/dev/iscsi/iscsi_ioctl.h
+++ b/sys/dev/iscsi/iscsi_ioctl.h
@@ -91,8 +91,8 @@ struct iscsi_session_state {
 struct iscsi_daemon_request {
 	unsigned int			idr_session_id;
 	struct iscsi_session_conf	idr_conf;
-	uint8_t				idr_spare_isid[6];
-	uint16_t			idr_spare_tsih;
+	uint8_t				idr_isid[6];
+	uint16_t			idr_tsih;
 	uint16_t			idr_spare_cid;
 	int				idr_spare[4];
 };
@@ -101,9 +101,9 @@ struct iscsi_daemon_handoff {
 	unsigned int			idh_session_id;
 	int				idh_socket;
 	char				idh_target_alias[ISCSI_ALIAS_LEN];
-	uint8_t				idh_isid[6];
-	uint16_t			idr_spare_tsih;
-	uint16_t			idr_spare_cid;
+	uint8_t				idh_spare_isid[6];
+	uint16_t			idh_tsih;
+	uint16_t			idh_spare_cid;
 	uint32_t			idh_statsn;
 	int				idh_header_digest;
 	int				idh_data_digest;