[SCSI] iscsi bugfixes: fix r2t handling

The iscsi tcp code can pluck multiple rt2s from the tasks's r2tqueue
in the xmit code. This can result in the task being queued on the xmit queue
but gettting completed at the same time.

This patch fixes the above bug by making the fifo a list so
we always remove the entry on the list del.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 21 insertions, 24 deletions

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 88dafdf45c4..ab324d984b8 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -185,11 +185,19 @@ iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
  * must be called with session lock
  */
 static void
-__iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+	struct iscsi_r2t_info *r2t;
 	struct scsi_cmnd *sc;
 
+	/* flush ctask's r2t queues */
+	while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
+		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
+			    sizeof(void*));
+		debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
+	}
+
 	sc = ctask->sc;
 	if (unlikely(!sc))
 		return;
@@ -374,6 +382,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 		spin_unlock(&session->lock);
 		return 0;
 	}
+
 	rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
 	BUG_ON(!rc);
 
@@ -399,7 +408,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	tcp_ctask->exp_r2tsn = r2tsn + 1;
 	tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
 	__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
-	__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+	list_move_tail(&ctask->running, &conn->xmitqueue);
 
 	scsi_queue_work(session->host, &conn->xmitwork);
 	conn->r2t_pdus_cnt++;
@@ -484,7 +493,7 @@ iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
 			goto copy_hdr;
 
 		spin_lock(&session->lock);
-		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
 		rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
 		spin_unlock(&session->lock);
 		break;
@@ -745,10 +754,11 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 done:
 	/* check for non-exceptional status */
 	if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-		debug_scsi("done [sc %lx res %d itt 0x%x]\n",
-			   (long)sc, sc->result, ctask->itt);
+		debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
+			   (long)sc, sc->result, ctask->itt,
+			   tcp_conn->in.hdr->flags);
 		spin_lock(&conn->session->lock);
-		__iscsi_ctask_cleanup(conn, ctask);
+		iscsi_tcp_cleanup_ctask(conn, ctask);
 		__iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
 		spin_unlock(&conn->session->lock);
 	}
@@ -769,7 +779,7 @@ iscsi_data_recv(struct iscsi_conn *conn)
 		break;
 	case ISCSI_OP_SCSI_CMD_RSP:
 		spin_lock(&conn->session->lock);
-		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
+		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
 		spin_unlock(&conn->session->lock);
 	case ISCSI_OP_TEXT_RSP:
 	case ISCSI_OP_LOGIN_RSP:
@@ -1308,7 +1318,7 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
 				    ctask->imm_count -
 				    ctask->unsol_count;
 
-		debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
+		debug_scsi("cmd [itt 0x%x total %d imm %d imm_data %d "
 			   "r2t_data %d]\n",
 			   ctask->itt, ctask->total_length, ctask->imm_count,
 			   ctask->unsol_count, tcp_ctask->r2t_data_count);
@@ -1636,7 +1646,7 @@ handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	}
 solicit_again:
 	/*
-	 * send Data-Out whitnin this R2T sequence.
+	 * send Data-Out within this R2T sequence.
 	 */
 	if (!r2t->data_count)
 		goto data_out_done;
@@ -1731,7 +1741,7 @@ handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_data_task *dtask = tcp_ctask->dtask;
-	int sent, rc;
+	int sent = 0, rc;
 
 	tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
 	iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
@@ -2002,20 +2012,6 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
 }
 
 static void
-iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_r2t_info *r2t;
-
-	/* flush ctask's r2t queues */
-	while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*)))
-		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
-			    sizeof(void*));
-
-	__iscsi_ctask_cleanup(conn, ctask);
-}
-
-static void
 iscsi_tcp_suspend_conn_rx(struct iscsi_conn *conn)
 {
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
@@ -2057,6 +2053,7 @@ iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
 	iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
 			   sizeof(struct iscsi_hdr));
 	tcp_mtask->xmstate = XMSTATE_IMM_HDR;
+	tcp_mtask->sent = 0;
 
 	if (mtask->data_count)
 		iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,