Commit fbb59ae2 authored by Ziye Yang's avatar Ziye Yang Committed by Tomasz Zawadzki
Browse files

iscsi: fix the recursive calling issue. 



After I review the function iscsi_conn_flush_pdus_internal,
I think that it may cause recursive function call issue. One of
the recursive calls in iscsi_conn_flush_pdus_internal
is:

spdk_iscsi_conn_free_pdu
spdk_iscsi_conn_handle_queued_datain_tasks
...
spdk_iscsi_task_cpl(&task->scsi);
...
process_read_task_completion
spdk_iscsi_task_response
iscsi_transfer_in
iscsi_send_datain
spdk_iscsi_conn_write_pdu
iscsi_conn_flush_pdus
iscsi_conn_flush_pdus_internal

So we have to create another list to solve this recursive issue
in the while loop. And we face the the similar issue in
NVMe/TCP before. With this patch, we can fix issues caused by
recursive calls.

Fixes #issue 1023

Signed-off-by: default avatarZiye Yang <ziye.yang@intel.com>
Change-Id: I7150b962bfb30e74f53ba1a2a826fb78c73d8ea6
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/472999


Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
parent e3d18b50

lib/iscsi/conn.c

+18 −12
Original line number Diff line number Diff line
@@ -1253,6 +1253,7 @@ iscsi_conn_flush_pdus_internal(struct spdk_iscsi_conn *conn) 
	uint32_t mapped_length = 0;

	struct spdk_iscsi_pdu *pdu;

	int pdu_length;

	TAILQ_HEAD(, spdk_iscsi_pdu) completed_pdus_list;



	pdu = TAILQ_FIRST(&conn->write_pdu_list);
@@ -1297,6 +1298,7 @@ iscsi_conn_flush_pdus_internal(struct spdk_iscsi_conn *conn) 
	 *  partially written, update its writev_offset so that next

	 *  time only the unwritten portion will be sent to writev().

	 */

	TAILQ_INIT(&completed_pdus_list);

	while (bytes > 0) {

		pdu_length = iscsi_get_pdu_length(pdu, conn->header_digest,

						  conn->data_digest);
@@ -1305,7 +1307,17 @@ iscsi_conn_flush_pdus_internal(struct spdk_iscsi_conn *conn) 
		if (bytes >= pdu_length) {

			bytes -= pdu_length;

			TAILQ_REMOVE(&conn->write_pdu_list, pdu, tailq);

			TAILQ_INSERT_TAIL(&completed_pdus_list, pdu, tailq);

			pdu = TAILQ_FIRST(&conn->write_pdu_list);

		} else {

			pdu->writev_offset += bytes;

			bytes = 0;

		}

	}



	while (!TAILQ_EMPTY(&completed_pdus_list)) {

		pdu = TAILQ_FIRST(&completed_pdus_list);

		TAILQ_REMOVE(&completed_pdus_list, pdu, tailq);

		if ((conn->full_feature) &&

		    (conn->sess->ErrorRecoveryLevel >= 1) &&

		    spdk_iscsi_is_deferred_free_pdu(pdu)) {
@@ -1316,12 +1328,6 @@ iscsi_conn_flush_pdus_internal(struct spdk_iscsi_conn *conn) 
		} else {

			spdk_iscsi_conn_free_pdu(conn, pdu);

		}



			pdu = TAILQ_FIRST(&conn->write_pdu_list);

		} else {

			pdu->writev_offset += bytes;

			bytes = 0;

		}

	}



	return TAILQ_EMPTY(&conn->write_pdu_list) ? 0 : 1;