iscsi-target: Add iser-target parameter keys + setup during login

This patch adds RDMAExtensions, InitiatorRecvDataSegmentLength and
TargetRecvDataSegmentLength parameters keys necessary for iser-target
login to occur.

This includes setting the necessary parameters during login path
code within iscsi_login_zero_tsih_s2(), and currently PAGE_SIZE
aligning the target's advertised MRDSL for immediate data and
unsolicited data-out incoming payloads.

v3 changes:
- Add iscsi_post_login_start_timers FIXME for ISER

v2 changes:

- Fix RDMAExtentions -> RDMAExtensions typo (andy)
- Drop unnecessary '== true' conditional checks for type bool

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c
index 84ce94a..f690be9 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -433,6 +433,28 @@
 			TYPERANGE_MARKINT, USE_INITIAL_ONLY);
 	if (!param)
 		goto out;
+	/*
+	 * Extra parameters for ISER from RFC-5046
+	 */
+	param = iscsi_set_default_param(pl, RDMAEXTENTIONS, INITIAL_RDMAEXTENTIONS,
+			PHASE_OPERATIONAL, SCOPE_SESSION_WIDE, SENDER_BOTH,
+			TYPERANGE_BOOL_AND, USE_LEADING_ONLY);
+	if (!param)
+		goto out;
+
+	param = iscsi_set_default_param(pl, INITIATORRECVDATASEGMENTLENGTH,
+			INITIAL_INITIATORRECVDATASEGMENTLENGTH,
+			PHASE_OPERATIONAL, SCOPE_CONNECTION_ONLY, SENDER_BOTH,
+			TYPERANGE_512_TO_16777215, USE_ALL);
+	if (!param)
+		goto out;
+
+	param = iscsi_set_default_param(pl, TARGETRECVDATASEGMENTLENGTH,
+			INITIAL_TARGETRECVDATASEGMENTLENGTH,
+			PHASE_OPERATIONAL, SCOPE_CONNECTION_ONLY, SENDER_BOTH,
+			TYPERANGE_512_TO_16777215, USE_ALL);
+	if (!param)
+		goto out;
 
 	*param_list_ptr = pl;
 	return 0;
@@ -442,19 +464,23 @@
 }
 
 int iscsi_set_keys_to_negotiate(
-	int sessiontype,
-	struct iscsi_param_list *param_list)
+	struct iscsi_param_list *param_list,
+	bool iser)
 {
 	struct iscsi_param *param;
 
+	param_list->iser = iser;
+
 	list_for_each_entry(param, &param_list->param_list, p_list) {
 		param->state = 0;
 		if (!strcmp(param->name, AUTHMETHOD)) {
 			SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, HEADERDIGEST)) {
-			SET_PSTATE_NEGOTIATE(param);
+			if (iser == false)
+				SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, DATADIGEST)) {
-			SET_PSTATE_NEGOTIATE(param);
+			if (iser == false)
+				SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, MAXCONNECTIONS)) {
 			SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, TARGETNAME)) {
@@ -473,7 +499,8 @@
 		} else if (!strcmp(param->name, IMMEDIATEDATA)) {
 			SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, MAXRECVDATASEGMENTLENGTH)) {
-			SET_PSTATE_NEGOTIATE(param);
+			if (iser == false)
+				SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, MAXXMITDATASEGMENTLENGTH)) {
 			continue;
 		} else if (!strcmp(param->name, MAXBURSTLENGTH)) {
@@ -502,6 +529,15 @@
 			SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, OFMARKINT)) {
 			SET_PSTATE_NEGOTIATE(param);
+		} else if (!strcmp(param->name, RDMAEXTENTIONS)) {
+			if (iser == true)
+				SET_PSTATE_NEGOTIATE(param);
+		} else if (!strcmp(param->name, INITIATORRECVDATASEGMENTLENGTH)) {
+			if (iser == true)
+				SET_PSTATE_NEGOTIATE(param);
+		} else if (!strcmp(param->name, TARGETRECVDATASEGMENTLENGTH)) {
+			if (iser == true)
+				SET_PSTATE_NEGOTIATE(param);
 		}
 	}
 
@@ -544,6 +580,12 @@
 			param->state &= ~PSTATE_NEGOTIATE;
 		else if (!strcmp(param->name, OFMARKINT))
 			param->state &= ~PSTATE_NEGOTIATE;
+		else if (!strcmp(param->name, RDMAEXTENTIONS))
+			param->state &= ~PSTATE_NEGOTIATE;
+		else if (!strcmp(param->name, INITIATORRECVDATASEGMENTLENGTH))
+			param->state &= ~PSTATE_NEGOTIATE;
+		else if (!strcmp(param->name, TARGETRECVDATASEGMENTLENGTH))
+			param->state &= ~PSTATE_NEGOTIATE;
 	}
 
 	return 0;
@@ -1759,6 +1801,9 @@
 		 * this key is not sent over the wire.
 		 */
 		if (!strcmp(param->name, MAXXMITDATASEGMENTLENGTH)) {
+			if (param_list->iser == true)
+				continue;
+
 			ops->MaxXmitDataSegmentLength =
 				simple_strtoul(param->value, &tmpptr, 0);
 			pr_debug("MaxXmitDataSegmentLength:     %s\n",
@@ -1804,6 +1849,22 @@
 				simple_strtoul(param->value, &tmpptr, 0);
 			pr_debug("IFMarkInt:                    %s\n",
 				param->value);
+		} else if (!strcmp(param->name, INITIATORRECVDATASEGMENTLENGTH)) {
+			ops->InitiatorRecvDataSegmentLength =
+				simple_strtoul(param->value, &tmpptr, 0);
+			pr_debug("InitiatorRecvDataSegmentLength: %s\n",
+				param->value);
+			ops->MaxRecvDataSegmentLength =
+					ops->InitiatorRecvDataSegmentLength;
+			pr_debug("Set MRDSL from InitiatorRecvDataSegmentLength\n");
+		} else if (!strcmp(param->name, TARGETRECVDATASEGMENTLENGTH)) {
+			ops->TargetRecvDataSegmentLength =
+				simple_strtoul(param->value, &tmpptr, 0);
+			pr_debug("TargetRecvDataSegmentLength:  %s\n",
+				param->value);
+			ops->MaxXmitDataSegmentLength =
+					ops->TargetRecvDataSegmentLength;
+			pr_debug("Set MXDSL from TargetRecvDataSegmentLength\n");
 		}
 	}
 	pr_debug("----------------------------------------------------"
@@ -1916,6 +1977,10 @@
 			ops->SessionType = !strcmp(param->value, DISCOVERY);
 			pr_debug("SessionType:                  %s\n",
 				param->value);
+		} else if (!strcmp(param->name, RDMAEXTENTIONS)) {
+			ops->RDMAExtensions = !strcmp(param->value, YES);
+			pr_debug("RDMAExtensions:               %s\n",
+				param->value);
 		}
 	}
 	pr_debug("----------------------------------------------------"