iscsi-target: remove support for obsolete markers

Support for markers is currently broken because of a bug in
iscsi_enforce_integrity_rules(): the "IFMarkInt_Reject" and
"OFMarkInt_Reject" variables are always equal to 1 in
iscsi_enforce_integrity_rules().

Moreover, fixed interval markers keys (IFMarker, OFMarker, IFMarkInt
and OFMarkInt) are obsolete according to iSCSI RFC 7143:

>From http://tools.ietf.org/html/rfc7143#section-13.25:

   13.25.  Obsoleted Keys

   This document obsoletes the following keys defined in [RFC3720]:
   IFMarker, OFMarker, OFMarkInt, and IFMarkInt.  However, iSCSI
   implementations compliant to this document may still receive these
   obsoleted keys -- i.e., in a responder role -- in a text negotiation.

   When an IFMarker or OFMarker key is received, a compliant iSCSI
   implementation SHOULD respond with the constant "Reject" value.  The
   implementation MAY alternatively respond with a "No" value.

   However, the implementation MUST NOT respond with a "NotUnderstood"
   value for either of these keys.

   When an IFMarkInt or OFMarkInt key is received, a compliant iSCSI
   implementation MUST respond with the constant "Reject" value.  The
   implementation MUST NOT respond with a "NotUnderstood" value for
   either of these keys.

This patch disables markers by turning the corresponding parameters to
read-only. The default value of IFMarker and OFMarker remains "No" but
the user cannot change it to "Yes" anymore. The new value of IFMarkInt
and OFMarkInt is "Reject".

(Drop left-over iscsi_get_value_from_number_range + make configfs
 parameters attrs R/W nops - nab)

Signed-off-by: Christophe Vu-Brugier <cvubrugier@fastmail.fm>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 0 insertions, 48 deletions

diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index b18edda3e8af..37d23e5e08dc 100644
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -809,54 +809,6 @@ void iscsit_inc_session_usage_count(struct iscsi_session *sess)
 	spin_unlock_bh(&sess->session_usage_lock);
 }
 
-/*
- *	Setup conn->if_marker and conn->of_marker values based upon
- *	the initial marker-less interval. (see iSCSI v19 A.2)
- */
-int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
-{
-	int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
-	/*
-	 * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
-	 */
-	u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
-	u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
-
-	if (conn->conn_ops->OFMarker) {
-		/*
-		 * Account for the first Login Command received not
-		 * via iscsi_recv_msg().
-		 */
-		conn->of_marker += ISCSI_HDR_LEN;
-		if (conn->of_marker <= OFMarkInt) {
-			conn->of_marker = (OFMarkInt - conn->of_marker);
-		} else {
-			login_ofmarker_count = (conn->of_marker / OFMarkInt);
-			next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
-					(login_ofmarker_count * MARKER_SIZE);
-			conn->of_marker = (next_marker - conn->of_marker);
-		}
-		conn->of_marker_offset = 0;
-		pr_debug("Setting OFMarker value to %u based on Initial"
-			" Markerless Interval.\n", conn->of_marker);
-	}
-
-	if (conn->conn_ops->IFMarker) {
-		if (conn->if_marker <= IFMarkInt) {
-			conn->if_marker = (IFMarkInt - conn->if_marker);
-		} else {
-			login_ifmarker_count = (conn->if_marker / IFMarkInt);
-			next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
-					(login_ifmarker_count * MARKER_SIZE);
-			conn->if_marker = (next_marker - conn->if_marker);
-		}
-		pr_debug("Setting IFMarker value to %u based on Initial"
-			" Markerless Interval.\n", conn->if_marker);
-	}
-
-	return 0;
-}
-
 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
 {
 	struct iscsi_conn *conn;