net/mlx5: Add exit route when waiting for FW

Currently, removing a device needs to get the driver interface lock before
doing any cleanup. If the driver is waiting in a loop for FW init, there
is no way to cancel the wait, instead the device cleanup waits for the
loop to conclude and release the lock.

To allow immediate response to remove device commands, check the TEARDOWN
flag while waiting for FW init, and exit the loop if it has been set.
Signed-off-by: Gavin Li <gavinl@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -189,7 +189,8 @@ static int wait_fw_init(struct mlx5_core_dev *dev, u32 max_wait_mili,
 		fw_initializing = ioread32be(&dev->iseg->initializing);
 		if (!(fw_initializing >> 31))
 			break;
-		if (time_after(jiffies, end)) {
+		if (time_after(jiffies, end) ||
+		    test_and_clear_bit(MLX5_BREAK_FW_WAIT, &dev->intf_state)) {
 			err = -EBUSY;
 			break;
 		}
@@ -1602,6 +1603,7 @@ static void remove_one(struct pci_dev *pdev)
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	struct devlink *devlink = priv_to_devlink(dev);
 
+	set_bit(MLX5_BREAK_FW_WAIT, &dev->intf_state);
 	devlink_unregister(devlink);
 	mlx5_sriov_disable(pdev);
 	mlx5_crdump_disable(dev);
@@ -1785,6 +1787,7 @@ static void shutdown(struct pci_dev *pdev)
 	int err;
 
 	mlx5_core_info(dev, "Shutdown was called\n");
+	set_bit(MLX5_BREAK_FW_WAIT, &dev->intf_state);
 	err = mlx5_try_fast_unload(dev);
 	if (err)
 		mlx5_unload_one(dev);

include/linux/mlx5/driver.h

@@ -632,6 +632,7 @@ enum mlx5_device_state {
 
 enum mlx5_interface_state {
 	MLX5_INTERFACE_STATE_UP = BIT(0),
+	MLX5_BREAK_FW_WAIT = BIT(1),
 };
 
 enum mlx5_pci_status {