4 files changed, 31 insertions, 0 deletions

diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c
index f86833fcf33c..f491f969ab95 100644
--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -1034,6 +1034,9 @@ TPG_PARAM_ATTR(ImmediateData, S_IRUGO | S_IWUSR);
 DEF_TPG_PARAM(MaxRecvDataSegmentLength);
 TPG_PARAM_ATTR(MaxRecvDataSegmentLength, S_IRUGO | S_IWUSR);
 
+DEF_TPG_PARAM(MaxXmitDataSegmentLength);
+TPG_PARAM_ATTR(MaxXmitDataSegmentLength, S_IRUGO | S_IWUSR);
+
 DEF_TPG_PARAM(MaxBurstLength);
 TPG_PARAM_ATTR(MaxBurstLength, S_IRUGO | S_IWUSR);
 
@@ -1079,6 +1082,7 @@ static struct configfs_attribute *lio_target_tpg_param_attrs[] = {
         &iscsi_tpg_param_InitialR2T.attr,
         &iscsi_tpg_param_ImmediateData.attr,
         &iscsi_tpg_param_MaxRecvDataSegmentLength.attr,
+        &iscsi_tpg_param_MaxXmitDataSegmentLength.attr,
         &iscsi_tpg_param_MaxBurstLength.attr,
         &iscsi_tpg_param_FirstBurstLength.attr,
         &iscsi_tpg_param_DefaultTime2Wait.attr,
diff --git a/drivers/target/iscsi/iscsi_target_core.h b/drivers/target/iscsi/iscsi_target_core.h
index 8a908b28d8b2..b26611aa5ff3 100644
--- a/drivers/target/iscsi/iscsi_target_core.h
+++ b/drivers/target/iscsi/iscsi_target_core.h
@@ -239,6 +239,7 @@ struct iscsi_conn_ops {
         u8      HeaderDigest;                   /* [0,1] == [None,CRC32C] */
         u8      DataDigest;                     /* [0,1] == [None,CRC32C] */
         u32     MaxRecvDataSegmentLength;       /* [512..2**24-1] */
+        u32     MaxXmitDataSegmentLength;       /* [512..2**24-1] */
         u8      OFMarker;                       /* [0,1] == [No,Yes] */
         u8      IFMarker;                       /* [0,1] == [No,Yes] */
         u32     OFMarkInt;                      /* [1..65535] */
diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c
index 0c4760fabfc0..40864ee70302 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -334,6 +334,13 @@ int iscsi_create_default_params(struct iscsi_param_list **param_list_ptr)
         if (!param)
                 goto out;
 
+        param = iscsi_set_default_param(pl, MAXXMITDATASEGMENTLENGTH,
+                        INITIAL_MAXXMITDATASEGMENTLENGTH,
+                        PHASE_OPERATIONAL, SCOPE_CONNECTION_ONLY, SENDER_BOTH,
+                        TYPERANGE_512_TO_16777215, USE_ALL);
+        if (!param)
+                goto out;
+
         param = iscsi_set_default_param(pl, MAXRECVDATASEGMENTLENGTH,
                         INITIAL_MAXRECVDATASEGMENTLENGTH,
                         PHASE_OPERATIONAL, SCOPE_CONNECTION_ONLY, SENDER_BOTH,
@@ -467,6 +474,8 @@ int iscsi_set_keys_to_negotiate(
                         SET_PSTATE_NEGOTIATE(param);
                 } else if (!strcmp(param->name, MAXRECVDATASEGMENTLENGTH)) {
                         SET_PSTATE_NEGOTIATE(param);
+                } else if (!strcmp(param->name, MAXXMITDATASEGMENTLENGTH)) {
+                        continue;
                 } else if (!strcmp(param->name, MAXBURSTLENGTH)) {
                         SET_PSTATE_NEGOTIATE(param);
                 } else if (!strcmp(param->name, FIRSTBURSTLENGTH)) {
@@ -1720,6 +1729,18 @@ void iscsi_set_connection_parameters(
         pr_debug("---------------------------------------------------"
                         "---------------\n");
         list_for_each_entry(param, &param_list->param_list, p_list) {
+                /*
+                 * Special case to set MAXXMITDATASEGMENTLENGTH from the
+                 * target requested MaxRecvDataSegmentLength, even though
+                 * this key is not sent over the wire.
+                 */
+                if (!strcmp(param->name, MAXXMITDATASEGMENTLENGTH)) {
+                        ops->MaxXmitDataSegmentLength =
+                                simple_strtoul(param->value, &tmpptr, 0);
+                        pr_debug("MaxXmitDataSegmentLength:     %s\n",
+                                param->value);
+                }
+
                 if (!IS_PSTATE_ACCEPTOR(param) && !IS_PSTATE_PROPOSER(param))
                         continue;
                 if (!strcmp(param->name, AUTHMETHOD)) {
diff --git a/drivers/target/iscsi/iscsi_target_parameters.h b/drivers/target/iscsi/iscsi_target_parameters.h
index 6a37fd6f1285..77a28b589d56 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.h
+++ b/drivers/target/iscsi/iscsi_target_parameters.h
@@ -70,6 +70,7 @@ extern void iscsi_set_session_parameters(struct iscsi_sess_ops *,
 #define INITIALR2T                      "InitialR2T"
 #define IMMEDIATEDATA                   "ImmediateData"
 #define MAXRECVDATASEGMENTLENGTH        "MaxRecvDataSegmentLength"
+#define MAXXMITDATASEGMENTLENGTH        "MaxXmitDataSegmentLength"
 #define MAXBURSTLENGTH                  "MaxBurstLength"
 #define FIRSTBURSTLENGTH                "FirstBurstLength"
 #define DEFAULTTIME2WAIT                "DefaultTime2Wait"
@@ -113,6 +114,10 @@ extern void iscsi_set_session_parameters(struct iscsi_sess_ops *,
 #define INITIAL_INITIALR2T                      YES
 #define INITIAL_IMMEDIATEDATA                   YES
 #define INITIAL_MAXRECVDATASEGMENTLENGTH        "8192"
+/*
+ * Match outgoing MXDSL default to incoming Open-iSCSI default
+ */
+#define INITIAL_MAXXMITDATASEGMENTLENGTH        "262144"
 #define INITIAL_MAXBURSTLENGTH                  "262144"
 #define INITIAL_FIRSTBURSTLENGTH                "65536"
 #define INITIAL_DEFAULTTIME2WAIT                "2"