[SRU][Bionic][PATCH 2/2] nvme-rdma: Don't flush delete_wq by default during remove_one

[Joseph Salisbury]

From: Max Gurtovoy <maxg at mellanox.com>

BugLink: http://bugs.launchpad.net/bugs/1764982

The .remove_one function is called for any ib_device removal.
In case the removed device has no reference in our driver, there
is no need to flush the work queue.

Reviewed-by: Israel Rukshin <israelr at mellanox.com>
Signed-off-by: Max Gurtovoy <maxg at mellanox.com>
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
Signed-off-by: Keith Busch <keith.busch at intel.com>
Signed-off-by: Jens Axboe <axboe at kernel.dk>
(cherry picked from commit 9bad0404ecd7594265cef04e176adeaa4ffbca4a)
Signed-off-by: Joseph Salisbury <joseph.salisbury at canonical.com>
---
 drivers/nvme/host/rdma.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 2a0bba7..65cfa6c 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -2027,6 +2027,20 @@ static struct nvmf_transport_ops nvme_rdma_transport = {
 static void nvme_rdma_remove_one(struct ib_device *ib_device, void *client_data)
 {
 	struct nvme_rdma_ctrl *ctrl;
+	struct nvme_rdma_device *ndev;
+	bool found = false;
+
+	mutex_lock(&device_list_mutex);
+	list_for_each_entry(ndev, &device_list, entry) {
+		if (ndev->dev == ib_device) {
+			found = true;
+			break;
+		}
+	}
+	mutex_unlock(&device_list_mutex);
+
+	if (!found)
+		return;
 
 	/* Delete all controllers using this device */
 	mutex_lock(&nvme_rdma_ctrl_mutex);
-- 
2.7.4