lib/iscsi: Add MaxR2TPerConnection to iSCSI options

Add MaxR2TPerConnection to iSCSI global options and make it configurable
by JSON RPC.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: Ida95e5c7dac301a22520656709e1aa4d611f31ef
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/3777
Community-CI: Broadcom CI
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

doc/jsonrpc.md

@@ -2978,6 +2978,7 @@ immediate_data                  | Optional | boolean | Session specific paramete
 error_recovery_level            | Optional | number  | Session specific parameter, ErrorRecoveryLevel (default: 0)
 allow_duplicated_isid           | Optional | boolean | Allow duplicated initiator session ID (default: `false`)
 max_large_datain_per_connection | Optional | number  | Max number of outstanding split read I/Os per connection (default: 64)
+max_r2t_per_connection          | Optional | number  | Max number of outstanding R2Ts per connection (default: 4)
 
 To load CHAP shared secret file, its path is required to specify explicitly in the parameter `auth_file`.
 
@@ -3063,7 +3064,8 @@ Example response:
     "disable_chap": true,
     "default_time2wait": 2,
     "require_chap": false,
-    "max_large_datain_per_connection": 64
+    "max_large_datain_per_connection": 64,
+    "max_r2t_per_connection": 4
   }
 }
 ~~~

lib/iscsi/iscsi.h

@@ -321,6 +321,7 @@ struct spdk_iscsi_opts {
 	uint32_t ErrorRecoveryLevel;
 	bool AllowDuplicateIsid;
 	uint32_t MaxLargeDataInPerConnection;
+	uint32_t MaxR2TPerConnection;
 };
 
 struct spdk_iscsi_globals {

lib/iscsi/iscsi_rpc.c

@@ -1717,6 +1717,7 @@ static const struct spdk_json_object_decoder rpc_set_iscsi_opts_decoders[] = {
 	{"error_recovery_level", offsetof(struct spdk_iscsi_opts, ErrorRecoveryLevel), spdk_json_decode_uint32, true},
 	{"allow_duplicated_isid", offsetof(struct spdk_iscsi_opts, AllowDuplicateIsid), spdk_json_decode_bool, true},
 	{"max_large_datain_per_connection", offsetof(struct spdk_iscsi_opts, MaxLargeDataInPerConnection), spdk_json_decode_uint32, true},
+	{"max_r2t_per_connection", offsetof(struct spdk_iscsi_opts, MaxR2TPerConnection), spdk_json_decode_uint32, true},
 };
 
 static void

lib/iscsi/iscsi_subsystem.c

@@ -407,6 +407,7 @@ iscsi_opts_init(struct spdk_iscsi_opts *opts)
 	opts->authfile = NULL;
 	opts->nodebase = NULL;
 	opts->MaxLargeDataInPerConnection = DEFAULT_MAX_LARGE_DATAIN_PER_CONNECTION;
+	opts->MaxR2TPerConnection = DEFAULT_MAXR2T;
 }
 
 struct spdk_iscsi_opts *
@@ -480,6 +481,7 @@ iscsi_opts_copy(struct spdk_iscsi_opts *src)
 	dst->mutual_chap = src->mutual_chap;
 	dst->chap_group = src->chap_group;
 	dst->MaxLargeDataInPerConnection = src->MaxLargeDataInPerConnection;
+	dst->MaxR2TPerConnection = src->MaxR2TPerConnection;
 
 	return dst;
 }
@@ -709,6 +711,11 @@ iscsi_opts_verify(struct spdk_iscsi_opts *opts)
 		return -EINVAL;
 	}
 
+	if (opts->MaxR2TPerConnection == 0) {
+		SPDK_ERRLOG("0 is invalid. MaxR2TPerConnection must be more than 0\n");
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -783,7 +790,7 @@ iscsi_set_global_params(struct spdk_iscsi_opts *opts)
 	g_iscsi.mutual_chap = opts->mutual_chap;
 	g_iscsi.chap_group = opts->chap_group;
 	g_iscsi.MaxLargeDataInPerConnection = opts->MaxLargeDataInPerConnection;
-	g_iscsi.MaxR2TPerConnection = DEFAULT_MAXR2T;
+	g_iscsi.MaxR2TPerConnection = opts->MaxR2TPerConnection;
 
 	iscsi_log_globals();
 
@@ -1502,6 +1509,8 @@ iscsi_opts_info_json(struct spdk_json_write_ctx *w)
 
 	spdk_json_write_named_uint32(w, "max_large_datain_per_connection",
 				     g_iscsi.MaxLargeDataInPerConnection);
+	spdk_json_write_named_uint32(w, "max_r2t_per_connection",
+				     g_iscsi.MaxR2TPerConnection);
 
 	spdk_json_write_object_end(w);
 }

scripts/rpc.py

@@ -853,7 +853,8 @@ if __name__ == "__main__":
             immediate_data=args.immediate_data,
             error_recovery_level=args.error_recovery_level,
             allow_duplicated_isid=args.allow_duplicated_isid,
-            max_large_datain_per_connection=args.max_large_datain_per_connection)
+            max_large_datain_per_connection=args.max_large_datain_per_connection,
+            max_r2t_per_connection=args.max_r2t_per_connection)
 
     p = subparsers.add_parser('iscsi_set_options', aliases=['set_iscsi_options'],
                               help="""Set options of iSCSI subsystem""")
@@ -878,6 +879,7 @@ if __name__ == "__main__":
     p.add_argument('-l', '--error-recovery-level', help='Negotiated parameter, ErrorRecoveryLevel', type=int)
     p.add_argument('-p', '--allow-duplicated-isid', help='Allow duplicated initiator session ID.', action='store_true')
     p.add_argument('-x', '--max-large-datain-per-connection', help='Max number of outstanding split read I/Os per connection', type=int)
+    p.add_argument('-k', '--max-r2t-per-connection', help='Max number of outstanding R2Ts per connection', type=int)
     p.set_defaults(func=iscsi_set_options)
 
     def iscsi_set_discovery_auth(args):

scripts/rpc/iscsi.py

@@ -21,7 +21,8 @@ def iscsi_set_options(
         immediate_data=None,
         error_recovery_level=None,
         allow_duplicated_isid=None,
-        max_large_datain_per_connection=None):
+        max_large_datain_per_connection=None,
+        max_r2t_per_connection=None):
     """Set iSCSI target options.
 
     Args:
@@ -43,6 +44,7 @@ def iscsi_set_options(
         error_recovery_level: Negotiated parameter, ErrorRecoveryLevel
         allow_duplicated_isid: Allow duplicated initiator session ID
         max_large_datain_per_connection: Max number of outstanding split read I/Os per connection (optional)
+        max_r2t_per_connection: Max number of outstanding R2Ts per connection (optional)
 
     Returns:
         True or False
@@ -85,6 +87,8 @@ def iscsi_set_options(
         params['allow_duplicated_isid'] = allow_duplicated_isid
     if max_large_datain_per_connection:
         params['max_large_datain_per_connection'] = max_large_datain_per_connection
+    if max_r2t_per_connection:
+        params['max_r2t_per_connection'] = max_r2t_per_connection
 
     return client.call('iscsi_set_options', params)
 

test/spdkcli/match_files/spdkcli_iscsi.test.match

@@ -18,6 +18,7 @@ o- iscsi .......................................................................
   | o- max_connections_per_session: 2 ........................................................................................ [...]
   | o- max_large_datain_per_connection: 64 ................................................................................... [...]
   | o- max_queue_depth: 64 ................................................................................................... [...]
+  | o- max_r2t_per_connection: 4 ............................................................................................. [...]
   | o- max_sessions: 128 ..................................................................................................... [...]
   | o- mutual_chap: False .................................................................................................... [...]
   | o- node_base: iqn.2016-06.io.spdk ........................................................................................ [...]