From 334c4241472916851d97aae209aedf1927ec84e3 Mon Sep 17 00:00:00 2001

From: Lijun Pan <lijunp213@gmail.com>

Date: Tue, 13 Apr 2021 03:31:44 -0500

Subject: [PATCH] ibmvnic: improve failover sysfs entry

References: bsc#1043990 ltc#155681 git-fixes

Patch-mainline: v5.13-rc1

Git-commit: 334c4241472916851d97aae209aedf1927ec84e3

The current implementation relies on H_IOCTL call to issue a

H_SESSION_ERR_DETECTED command to let the hypervisor to send a failover

signal. However, it may not work if there is no backup device or if

the vnic is already in error state,

e.g., "ibmvnic 30000003 env3: rx buffer returned with rc 6".

Add a last resort, that is to schedule a failover reset via CRQ command.

Signed-off-by: Lijun Pan <lijunp213@gmail.com>

Signed-off-by: David S. Miller <davem@davemloft.net>

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 drivers/net/ethernet/ibm/ibmvnic.c | 14 ++++++++------

 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c

index ee9bf18c597f..0961d36833d5 100644

--- a/drivers/net/ethernet/ibm/ibmvnic.c

+++ b/drivers/net/ethernet/ibm/ibmvnic.c

@@ -5503,7 +5503,7 @@ static ssize_t failover_store(struct device *dev, struct device_attribute *attr,

 	if (rc) {

 		netdev_err(netdev, "Couldn't retrieve session token, rc %ld\n",

 			   rc);

-		return -EINVAL;

+		goto last_resort;

 	}

 	session_token = (__be64)retbuf[0];

@@ -5511,15 +5511,17 @@ static ssize_t failover_store(struct device *dev, struct device_attribute *attr,

 		   be64_to_cpu(session_token));

 	rc = plpar_hcall_norets(H_VIOCTL, adapter->vdev->unit_address,

 				H_SESSION_ERR_DETECTED, session_token, 0, 0);

-	if (rc) {

-		netdev_err(netdev, "Client initiated failover failed, rc %ld\n",

+	if (rc)

+		netdev_err(netdev,

+			   "H_VIOCTL initiated failover failed, rc %ld\n",

 			   rc);

-		return -EINVAL;

-	}

+

+last_resort:

+	netdev_dbg(netdev, "Trying to send CRQ_CMD, the last resort\n");

+	ibmvnic_reset(adapter, VNIC_RESET_FAILOVER);

 	return count;

 }

-

 static DEVICE_ATTR_WO(failover);

 static unsigned long ibmvnic_get_desired_dma(struct vio_dev *vdev)

-- 

2.26.2