ibmvnic: Fix error handling when registering long-term-mapped buffers

The patch stores the return code of the REQUEST_MAP_RSP sub-CRQ command
in the private data structure, where it can be later checked during
device open or a reset.

In the case of a reset, the mapping request to the vNIC Server may fail,
especially in the case of a partition migration. The driver attempts to
handle this by re-allocating the buffer and re-sending the mapping request.

The original error handling implementation was removed. The separate
function handling the REQUEST_MAP response message was also removed,
since it is now simple enough to be handled in the ibmvnic_handle_crq
function.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/ibmvnic.c

@@ -163,16 +163,6 @@ static long h_reg_sub_crq(unsigned long unit_address, unsigned long token,
 	return rc;
 }
 
-static void reset_long_term_buff(struct ibmvnic_adapter *adapter,
-				 struct ibmvnic_long_term_buff *ltb)
-{
-	memset(ltb->buff, 0, ltb->size);
-
-	init_completion(&adapter->fw_done);
-	send_request_map(adapter, ltb->addr, ltb->size, ltb->map_id);
-	wait_for_completion(&adapter->fw_done);
-}
-
 static int alloc_long_term_buff(struct ibmvnic_adapter *adapter,
 				struct ibmvnic_long_term_buff *ltb, int size)
 {
@@ -193,6 +183,12 @@ static int alloc_long_term_buff(struct ibmvnic_adapter *adapter,
 	send_request_map(adapter, ltb->addr,
 			 ltb->size, ltb->map_id);
 	wait_for_completion(&adapter->fw_done);
+
+	if (adapter->fw_done_rc) {
+		dev_err(dev, "Couldn't map long term buffer,rc = %d\n",
+			adapter->fw_done_rc);
+		return -1;
+	}
 	return 0;
 }
 
@@ -210,6 +206,24 @@ static void free_long_term_buff(struct ibmvnic_adapter *adapter,
 	dma_free_coherent(dev, ltb->size, ltb->buff, ltb->addr);
 }
 
+static int reset_long_term_buff(struct ibmvnic_adapter *adapter,
+				struct ibmvnic_long_term_buff *ltb)
+{
+	memset(ltb->buff, 0, ltb->size);
+
+	init_completion(&adapter->fw_done);
+	send_request_map(adapter, ltb->addr, ltb->size, ltb->map_id);
+	wait_for_completion(&adapter->fw_done);
+
+	if (adapter->fw_done_rc) {
+		dev_info(&adapter->vdev->dev,
+			 "Reset failed, attempting to free and reallocate buffer\n");
+		free_long_term_buff(adapter, ltb);
+		return alloc_long_term_buff(adapter, ltb, ltb->size);
+	}
+	return 0;
+}
+
 static void deactivate_rx_pools(struct ibmvnic_adapter *adapter)
 {
 	int i;
@@ -366,13 +380,15 @@ static int reset_rx_pools(struct ibmvnic_adapter *adapter)
 {
 	struct ibmvnic_rx_pool *rx_pool;
 	int rx_scrqs;
-	int i, j;
+	int i, j, rc;
 
 	rx_scrqs = be32_to_cpu(adapter->login_rsp_buf->num_rxadd_subcrqs);
 	for (i = 0; i < rx_scrqs; i++) {
 		rx_pool = &adapter->rx_pool[i];
 
-		reset_long_term_buff(adapter, &rx_pool->long_term_buff);
+		rc = reset_long_term_buff(adapter, &rx_pool->long_term_buff);
+		if (rc)
+			return rc;
 
 		for (j = 0; j < rx_pool->size; j++)
 			rx_pool->free_map[j] = j;
@@ -494,13 +510,15 @@ static int reset_tx_pools(struct ibmvnic_adapter *adapter)
 {
 	struct ibmvnic_tx_pool *tx_pool;
 	int tx_scrqs;
-	int i, j;
+	int i, j, rc;
 
 	tx_scrqs = be32_to_cpu(adapter->login_rsp_buf->num_txsubm_subcrqs);
 	for (i = 0; i < tx_scrqs; i++) {
 		tx_pool = &adapter->tx_pool[i];
 
-		reset_long_term_buff(adapter, &tx_pool->long_term_buff);
+		rc = reset_long_term_buff(adapter, &tx_pool->long_term_buff);
+		if (rc)
+			return rc;
 
 		memset(tx_pool->tx_buff, 0,
 		       adapter->req_tx_entries_per_subcrq *
@@ -3075,36 +3093,6 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq,
 	return 0;
 }
 
-static void handle_request_map_rsp(union ibmvnic_crq *crq,
-				   struct ibmvnic_adapter *adapter)
-{
-	struct device *dev = &adapter->vdev->dev;
-	u8 map_id = crq->request_map_rsp.map_id;
-	int tx_subcrqs;
-	int rx_subcrqs;
-	long rc;
-	int i;
-
-	tx_subcrqs = be32_to_cpu(adapter->login_rsp_buf->num_txsubm_subcrqs);
-	rx_subcrqs = be32_to_cpu(adapter->login_rsp_buf->num_rxadd_subcrqs);
-
-	rc = crq->request_map_rsp.rc.code;
-	if (rc) {
-		dev_err(dev, "Error %ld in REQUEST_MAP_RSP\n", rc);
-		adapter->map_id--;
-		/* need to find and zero tx/rx_pool map_id */
-		for (i = 0; i < tx_subcrqs; i++) {
-			if (adapter->tx_pool[i].long_term_buff.map_id == map_id)
-				adapter->tx_pool[i].long_term_buff.map_id = 0;
-		}
-		for (i = 0; i < rx_subcrqs; i++) {
-			if (adapter->rx_pool[i].long_term_buff.map_id == map_id)
-				adapter->rx_pool[i].long_term_buff.map_id = 0;
-		}
-	}
-	complete(&adapter->fw_done);
-}
-
 static void handle_request_unmap_rsp(union ibmvnic_crq *crq,
 				     struct ibmvnic_adapter *adapter)
 {
@@ -3385,7 +3373,8 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
 		handle_query_map_rsp(crq, adapter);
 		break;
 	case REQUEST_MAP_RSP:
-		handle_request_map_rsp(crq, adapter);
+		adapter->fw_done_rc = crq->request_map_rsp.rc.code;
+		complete(&adapter->fw_done);
 		break;
 	case REQUEST_UNMAP_RSP:
 		handle_request_unmap_rsp(crq, adapter);

drivers/net/ethernet/ibm/ibmvnic.h

@@ -988,6 +988,7 @@ struct ibmvnic_adapter {
 	spinlock_t error_list_lock;
 
 	struct completion fw_done;
+	int fw_done_rc;
 
 	/* partner capabilities */
 	u64 min_tx_queues;