iscsi-target: Expose default_erl as TPG attribute

This patch exposes default_erl as a TPG attribute so that it may be
set TPG wide in demo-mode, but still allow the existing NodeACL
attribute to be overridden on a per initiator basis.

Reported-by: Arshad Hussain <[e-mail]>
Signed-off-by: Nicholas Bellinger <[e-mail]>

drivers/target/iscsi/iscsi_target_configfs.c

···
  */
 DEF_TPG_ATTRIB(demo_mode_discovery);
 TPG_ATTR(demo_mode_discovery, S_IRUGO | S_IWUSR);
+/*
+ * Define iscsi_tpg_attrib_s_default_erl
+ */
+DEF_TPG_ATTRIB(default_erl);
+TPG_ATTR(default_erl, S_IRUGO | S_IWUSR);
 
 static struct configfs_attribute *lio_target_tpg_attrib_attrs[] = {
 	&iscsi_tpg_attrib_authentication.attr,
···
 	&iscsi_tpg_attrib_demo_mode_write_protect.attr,
 	&iscsi_tpg_attrib_prod_mode_write_protect.attr,
 	&iscsi_tpg_attrib_demo_mode_discovery.attr,
+	&iscsi_tpg_attrib_default_erl.attr,
 	NULL,
 };
 
···
 {
 	struct iscsi_node_acl *acl = container_of(se_acl, struct iscsi_node_acl,
 				se_node_acl);
+	struct se_portal_group *se_tpg = se_acl->se_tpg;
+	struct iscsi_portal_group *tpg = container_of(se_tpg,
+				struct iscsi_portal_group, tpg_se_tpg);
 
 	acl->node_attrib.nacl = acl;
-	iscsit_set_default_node_attribues(acl);
+	iscsit_set_default_node_attribues(acl, tpg);
 }
 
 static int lio_check_stop_free(struct se_cmd *se_cmd)

drivers/target/iscsi/iscsi_target_core.h

···
 #define NA_RANDOM_DATAIN_PDU_OFFSETS	0
 #define NA_RANDOM_DATAIN_SEQ_OFFSETS	0
 #define NA_RANDOM_R2T_OFFSETS		0
-#define NA_DEFAULT_ERL			0
-#define NA_DEFAULT_ERL_MAX		2
-#define NA_DEFAULT_ERL_MIN		0
 
 /* struct iscsi_tpg_attrib sanity values */
 #define TA_AUTHENTICATION		1
···
 /* Disabled by default in production mode w/ explict ACLs */
 #define TA_PROD_MODE_WRITE_PROTECT	0
 #define TA_DEMO_MODE_DISCOVERY		1
+#define TA_DEFAULT_ERL			0
 #define TA_CACHE_CORE_NPS		0
 
 
···
 	u32			demo_mode_write_protect;
 	u32			prod_mode_write_protect;
 	u32			demo_mode_discovery;
+	u32			default_erl;
 	struct iscsi_portal_group *tpg;
 };
 

drivers/target/iscsi/iscsi_target_nodeattrib.c

···
 }
 
 void iscsit_set_default_node_attribues(
-	struct iscsi_node_acl *acl)
+	struct iscsi_node_acl *acl,
+	struct iscsi_portal_group *tpg)
 {
 	struct iscsi_node_attrib *a = &acl->node_attrib;
 
···
 	a->random_datain_pdu_offsets = NA_RANDOM_DATAIN_PDU_OFFSETS;
 	a->random_datain_seq_offsets = NA_RANDOM_DATAIN_SEQ_OFFSETS;
 	a->random_r2t_offsets = NA_RANDOM_R2T_OFFSETS;
-	a->default_erl = NA_DEFAULT_ERL;
+	a->default_erl = tpg->tpg_attrib.default_erl;
 }
 
 int iscsit_na_dataout_timeout(

drivers/target/iscsi/iscsi_target_nodeattrib.h

···
 #ifndef ISCSI_TARGET_NODEATTRIB_H
 #define ISCSI_TARGET_NODEATTRIB_H
 
-extern void iscsit_set_default_node_attribues(struct iscsi_node_acl *);
+extern void iscsit_set_default_node_attribues(struct iscsi_node_acl *,
+					      struct iscsi_portal_group *);
 extern int iscsit_na_dataout_timeout(struct iscsi_node_acl *, u32);
 extern int iscsit_na_dataout_timeout_retries(struct iscsi_node_acl *, u32);
 extern int iscsit_na_nopin_timeout(struct iscsi_node_acl *, u32);

drivers/target/iscsi/iscsi_target_tpg.c

···
 	a->demo_mode_write_protect = TA_DEMO_MODE_WRITE_PROTECT;
 	a->prod_mode_write_protect = TA_PROD_MODE_WRITE_PROTECT;
 	a->demo_mode_discovery = TA_DEMO_MODE_DISCOVERY;
+	a->default_erl = TA_DEFAULT_ERL;
 }
 
 int iscsit_tpg_add_portal_group(struct iscsi_tiqn *tiqn, struct iscsi_portal_group *tpg)
···
 	pr_debug("iSCSI_TPG[%hu] - Demo Mode Discovery bit:"
 		" %s\n", tpg->tpgt, (a->demo_mode_discovery) ?
 		"ON" : "OFF");
+
+	return 0;
+}
+
+int iscsit_ta_default_erl(
+	struct iscsi_portal_group *tpg,
+	u32 default_erl)
+{
+	struct iscsi_tpg_attrib *a = &tpg->tpg_attrib;
+
+	if ((default_erl != 0) && (default_erl != 1) && (default_erl != 2)) {
+		pr_err("Illegal value for default_erl: %u\n", default_erl);
+		return -EINVAL;
+	}
+
+	a->default_erl = default_erl;
+	pr_debug("iSCSI_TPG[%hu] - DefaultERL: %u\n", tpg->tpgt, a->default_erl);
 
 	return 0;
 }

drivers/target/iscsi/iscsi_target_tpg.h

···
 extern int iscsit_ta_demo_mode_write_protect(struct iscsi_portal_group *, u32);
 extern int iscsit_ta_prod_mode_write_protect(struct iscsi_portal_group *, u32);
 extern int iscsit_ta_demo_mode_discovery(struct iscsi_portal_group *, u32);
+extern int iscsit_ta_default_erl(struct iscsi_portal_group *, u32);
 
 #endif /* ISCSI_TARGET_TPG_H */