fixes(istgt): leaving recvlowat as 1 to read data at earliest (#231)

- log for op_text response

- reading immediate flag from correct bit

- commented out unused code

- Not closing the connection on logout request which will be closed only when client triggers it

Signed-off-by: Vitta <[email protected]>

Author: vishnuitta

src/istgt_iscsi.c

@@ -279,11 +279,12 @@ istgt_iscsi_read_pdu(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 	iovec[0].iov_len = 4 * pdu->total_ahs_len;
 
 	/* Header Digest */
-	iovec[1].iov_base = pdu->header_digest;
 	if (conn->header_digest) {
+		iovec[1].iov_base = pdu->header_digest;
 		iovec[1].iov_len = ISCSI_DIGEST_LEN;
 		total += ISCSI_DIGEST_LEN;
 	} else {
+		iovec[1].iov_base = NULL;
 		iovec[1].iov_len = 0;
 	}
 
@@ -313,11 +314,12 @@ istgt_iscsi_read_pdu(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 	iovec[2].iov_len = ISCSI_ALIGN(pdu->data_segment_len);
 
 	/* Data Digest */
-	iovec[3].iov_base = pdu->data_digest;
 	if (conn->data_digest && data_len != 0) {
+		iovec[3].iov_base = pdu->data_digest;
 		iovec[3].iov_len = ISCSI_DIGEST_LEN;
 		total += ISCSI_DIGEST_LEN;
 	} else {
+		iovec[3].iov_base = NULL;
 		iovec[3].iov_len = 0;
 	}
 
@@ -349,7 +351,7 @@ istgt_iscsi_read_pdu(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 		for (i = 0; i < 4; i++) {
 			if (iovec[i].iov_len != 0 && iovec[i].iov_len > (size_t)rc) {
 				iovec[i].iov_base
-					= (void *) (((uintptr_t)iovec[i].iov_base) + rc);
+					= (void *) (((char *)iovec[i].iov_base) + rc);
 				iovec[i].iov_len -= rc;
 				break;
 			} else {
@@ -680,8 +682,8 @@ istgt_iscsi_write_pdu_internal(CONN_Ptr conn, ISCSI_PDU_Ptr pdu, ISTGT_LU_CMD_Pt
 		rc = writev(conn->sock, &iovec[0], 5);
 		if (rc < 0) {
 			now = time(NULL);
-			ISTGT_ERRLOG("writev() failed (errno=%d,%s,time=%f) for opcode:0x%2.2x CSN:0x%x\n",
-				errno, conn->initiator_name, difftime(now, start), lu_cmd->cdb0, lu_cmd->CmdSN);
+			ISTGT_ERRLOG("writev() failed (errno=%d,%s,time=%f) for opcode:%d cdb:0x%2.2x CSN:0x%x\n",
+				errno, conn->initiator_name, difftime(now, start), opcode, lu_cmd->cdb0, lu_cmd->CmdSN);
 			return (-1);
 		}
 		nbytes -= rc;
@@ -2508,6 +2510,8 @@ istgt_iscsi_op_text(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 	uint32_t sMaxCmdSN = 0;
 	uint32_t cStatSN = 0;
 	int  step = 0;
+	int8_t sendtargets_discovery = 0;
+
 	if (!conn->full_feature) {
 		ISTGT_ERRLOG("before Full Feature\n");
 		return (-1);
@@ -2519,7 +2523,7 @@ istgt_iscsi_op_text(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 	memset(data, 0, alloc_len);
 
 	cp = (uint8_t *) &pdu->bhs;
-	I_bit = BGET8(&cp[0], 7);
+	I_bit = BGET8(&cp[0], 6);
 	F_bit = BGET8(&cp[1], 7);
 	C_bit = BGET8(&cp[1], 6);
 
@@ -2623,6 +2627,7 @@ istgt_iscsi_op_text(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 				conn->initiator_name,
 				conn->initiator_addr,
 				val, data, alloc_len, data_len);
+			sendtargets_discovery = 1;
 			SESS_MTX_LOCK(conn);
 		} else {
 			if (strcasecmp(val, "ALL") == 0) {
@@ -2635,6 +2640,7 @@ istgt_iscsi_op_text(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 					conn->initiator_name,
 					conn->initiator_addr,
 					val, data, alloc_len, data_len);
+				sendtargets_discovery = 2;
 				SESS_MTX_LOCK(conn);
 			}
 		}
@@ -2689,6 +2695,8 @@ istgt_iscsi_op_text(CONN_Ptr conn, ISCSI_PDU_Ptr pdu)
 		return (-1);
 	}
 
+	ISTGT_NOTICELOG("queued op_text response: %s", (sendtargets_discovery == 1) ? "sendtargets_discovery" :
+	    ((sendtargets_discovery == 2) ? "sendtargets_nondiscovery" : ""));
 	/* update internal variables */
 	istgt_iscsi_copy_param2var(conn);
 	/* check value */
@@ -5343,7 +5351,7 @@ wait_all_task(CONN_Ptr conn)
 		conn->id, conn->running_tasks);
 }
 
-
+#if 0
 static void
 snd_cleanup(void *arg)
 {
@@ -5428,6 +5436,7 @@ worker_cleanup(void *arg)
 	MTX_UNLOCK(&g_conns_mutex);
 	ISTGT_TRACELOG(ISTGT_TRACE_DEBUG, "cancel cleanup UNLOCK\n");
 }
+#endif
 
 const char lu_task_typ[4][12] = {
 	"RESPONSE",
@@ -5724,7 +5733,7 @@ sender(void *arg)
 	pthread_set_name_np(slf, tinfo);
 #endif
 
-	pthread_cleanup_push(snd_cleanup, (void *)conn);
+//	pthread_cleanup_push(snd_cleanup, (void *)conn);
 	memset(&abstime, 0, sizeof (abstime));
 	/* handle DATA-IN/SCSI status */
 	ISTGT_TRACELOG(ISTGT_TRACE_DEBUG, "sender loop start (%d)\n", conn->id);
@@ -5882,7 +5891,7 @@ sender(void *arg)
 //		MTX_UNLOCK(&conn->wpdu_mutex);
 	}
 	// MTX_UNLOCK(&conn->sender_mutex);
-	pthread_cleanup_pop(0);
+//	pthread_cleanup_pop(0);
 	ISTGT_NOTICELOG("sender loop ended (%d:%d:%d)\n", conn->id, conn->epfd, ntohs(conn->iport));
 	return (NULL);
 }
@@ -5929,22 +5938,21 @@ worker(void *arg)
 // #endif
 
 	events.data.fd = conn->sock;
-		events.events = EPOLLIN;
-		rc = epoll_ctl(epfd, EPOLL_CTL_ADD, conn->sock, &events);
-		if (rc == -1) {
+	events.events = EPOLLIN;
+	rc = epoll_ctl(epfd, EPOLL_CTL_ADD, conn->sock, &events);
+	if (rc == -1) {
 		ISTGT_ERRLOG("epoll_ctl() failed\n");
 		close(epfd);
 		return (NULL);
-		}
+	}
 	events.data.fd = conn->task_pipe[0];
-		events.events = EPOLLIN;
-		rc = epoll_ctl(epfd, EPOLL_CTL_ADD, conn->task_pipe[0], &events);
-		if (rc == -1) {
+	events.events = EPOLLIN;
+	rc = epoll_ctl(epfd, EPOLL_CTL_ADD, conn->task_pipe[0], &events);
+	if (rc == -1) {
 		ISTGT_ERRLOG("epoll_ctl() failed\n");
 		close(epfd);
 		return (NULL);
-		}
-
+	}
 
 	// TODO
 	// if (!conn->istgt->daemon) {
@@ -6019,7 +6027,7 @@ worker(void *arg)
 	conn->exec_lu_task = NULL;
 	lu_task = NULL;
 
-	pthread_cleanup_push(worker_cleanup, conn);
+//	pthread_cleanup_push(worker_cleanup, conn);
 	pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
 
 	/* create sender thread */
@@ -6097,22 +6105,23 @@ worker(void *arg)
 			if ((events.events & EPOLLERR) ||
 					(events.events & EPOLLHUP) ||
 					(!(events.events & EPOLLIN))) {
-				ISTGT_ERRLOG("close conn %d\n", errno);
+				ISTGT_ERRLOG("close conn events %d\n", events.events);
 				break;
 			}
 
 			rc = istgt_iscsi_read_pdu(conn, &conn->pdu);
 			if (rc < 0) {
 				if (errno == EAGAIN) {
+					ISTGT_ERRLOG("close conn %d %d\n", errno, events.events);
 					break;
 				}
 				if (conn->state != CONN_STATE_EXITING) {
 					ISTGT_ERRLOG("conn->state = %d\n", conn->state);
 				}
 				if (conn->state != CONN_STATE_RUNNING) {
 					if (errno == EINPROGRESS) {
-						sleep(1);
-						continue;
+						ISTGT_ERRLOG("iscsi_read_pdu shouldn't get EINPROGRESS");
+						break;
 					}
 					if (errno == ECONNRESET
 						|| errno == ETIMEDOUT) {
@@ -6139,7 +6148,6 @@ worker(void *arg)
 				break;
 			} else if (rc == 1) { // means successful logout ISCSI_OP_LOGOUT
 				ISTGT_TRACELOG(ISTGT_TRACE_ISCSI, "logout received\n");
-				break;
 			}
 
 			if (conn->pdu.ahs != NULL) {
@@ -6273,7 +6281,6 @@ worker(void *arg)
 
 	cleanup_exit:
 ;
-	pthread_cleanup_pop(0);
 	conn->state = CONN_STATE_EXITING;
 	if (conn->sess != NULL) {
 		lu = conn->sess->lu;
@@ -6480,14 +6487,6 @@ istgt_create_conn(ISTGT_Ptr istgt, PORTAL_Ptr portal, int sock, struct sockaddr
 		ISTGT_ERRLOG("istgt_set_sendtimeo() failed\n");
 		goto error_return;
 	}
-#if defined(ISTGT_USE_IOVEC)
-	/* set low water mark */
-	rc = istgt_set_recvlowat(conn->sock, ISCSI_BHS_LEN);
-	if (rc != 0) {
-		ISTGT_ERRLOG("istgt_set_recvlowat() failed\n");
-		goto error_return;
-	}
-#endif
 
 	rc = pipe(conn->task_pipe);
 	if (rc != 0) {