iscsi-target: Add tpg_enabled_sendtargets for disabled discovery

This patch adds a new tpg_enabled_sendtargets configfs attribute
to allow in-band sendtargets discovery information to include
target-portal-groups (TPGs) in !TPG_STATE_ACTIVE state.

This functionality is useful for clustered iSCSI targets, where
TPGTs handled on remote cluster nodes should be advertised in
the SendTargets response.

By default, this new attribute retains the default behaviour of
existing code which to ignore portal-groups in !TPG_STATE_ACTIVE
state.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/target/iscsi/iscsi_target_tpg.c b/drivers/target/iscsi/iscsi_target_tpg.c
index 968068ffcb1c..8262a853e888 100644
--- a/drivers/target/iscsi/iscsi_target_tpg.c
+++ b/drivers/target/iscsi/iscsi_target_tpg.c
@@ -226,6 +226,7 @@ static void iscsit_set_default_tpg_attribs(struct iscsi_portal_group *tpg)
 	a->default_erl = TA_DEFAULT_ERL;
 	a->t10_pi = TA_DEFAULT_T10_PI;
 	a->fabric_prot_type = TA_DEFAULT_FABRIC_PROT_TYPE;
+	a->tpg_enabled_sendtargets = TA_DEFAULT_TPG_ENABLED_SENDTARGETS;
 }
 
 int iscsit_tpg_add_portal_group(struct iscsi_tiqn *tiqn, struct iscsi_portal_group *tpg)
@@ -892,3 +893,21 @@ int iscsit_ta_fabric_prot_type(
 
 	return 0;
 }
+
+int iscsit_ta_tpg_enabled_sendtargets(
+	struct iscsi_portal_group *tpg,
+	u32 flag)
+{
+	struct iscsi_tpg_attrib *a = &tpg->tpg_attrib;
+
+	if ((flag != 0) && (flag != 1)) {
+		pr_err("Illegal value %d\n", flag);
+		return -EINVAL;
+	}
+
+	a->tpg_enabled_sendtargets = flag;
+	pr_debug("iSCSI_TPG[%hu] - TPG enabled bit required for SendTargets:"
+		" %s\n", tpg->tpgt, (a->tpg_enabled_sendtargets) ? "ON" : "OFF");
+
+	return 0;
+}