Subject: Re: [PATCH V2 net] net/mlx4_core: Preserve pci_dev_data after __mlx4_remove_one()

From: Sergei Shtylyov <[email-masked]>
Date: Sun, 13 Apr 2014 15:06:10 +0400

Hello.

On 13-04-2014 7:22, Wei Yang wrote:

> pci_match_id() just match the static pci_device_id, which may return NULL if
> someone binds the driver to a device manually using
> /sys/bus/pci/drivers/.../new_id.

> This patch wrap up a helper function __mlx4_remove_one() which does the tear
> down function but preserve the drv_data. Functions like
> mlx4_pci_err_detected() and mlx4_restart_one() will call this one with out
> releasing drvdata.

> Fixes: 97a5221 "net/mlx4_core: pass pci_device_id.driver_data to __mlx4_init_one during reset".

> CC: Bjorn Helgaas <[email-masked]>
> CC: Amir Vadai <[email-masked]>
> CC: Jack Morgenstein <[email-masked]>
> CC: Or Gerlitz <[email-masked]>
> Signed-off-by: Wei Yang <[email-masked]>
> Acked-by: Jack Morgenstein <[email-masked]>

[...]

> diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
> index f0ae95f..b6d60e2 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/main.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/main.c
[...]
> @@ -2604,85 +2598,112 @@ err_disable_pdev:
>
>   static int mlx4_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
>   {
> +	struct mlx4_priv *priv;
> +	struct mlx4_dev *dev;
> +
>   	printk_once(KERN_INFO "%s", mlx4_version);
>
> +	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> +	if (!priv) {
> +		return -ENOMEM;
> +	}

    {} not needed here.

[...]
> +	/* in SRIOV it is not allowed to unload the pf's
> +	 * driver while there are alive vf's */
> +	if (mlx4_is_master(dev)) {
> +		if (mlx4_how_many_lives_vf(dev))

    Could be folded into single *if*.

> +			printk(KERN_ERR "Removing PF when there are assigned VF's !!!\n");
> +	}
> +	mlx4_stop_sense(dev);
> +	mlx4_unregister_device(dev);
[...]
> +	for (p = 1; p <= dev->caps.num_ports; p++) {
> +		mlx4_cleanup_port_info(&priv->port[p]);
> +		mlx4_CLOSE_PORT(dev, p);
> +	}
> +
> +	if (mlx4_is_master(dev))
> +		mlx4_free_resource_tracker(dev,
> +				   RES_TR_FREE_SLAVES_ONLY);

    Please re-align this line so that it starts right under 'dev'.

[...]
>
> -		if (!mlx4_is_slave(dev))
> -			mlx4_free_ownership(dev);
> +	if (mlx4_is_master(dev))
> +		mlx4_free_resource_tracker(dev,
> +				   RES_TR_FREE_STRUCTS_ONLY);

    Likewise.

[...]
> @@ -2755,11 +2776,13 @@ static pci_ers_result_t mlx4_pci_err_detected(struct pci_dev *pdev,
>
>   static pci_ers_result_t mlx4_pci_slot_reset(struct pci_dev *pdev)
>   {
> -	const struct pci_device_id *id;
> -	int ret;
> +	struct mlx4_dev	 *dev  = pci_get_drvdata(pdev);
> +	struct mlx4_priv *priv = mlx4_priv(dev);
> +	int		  pci_dev_data;

    Doesn't seem that this variable is necessary.

> +	int               ret;
>
> -	id = pci_match_id(mlx4_pci_table, pdev);
> -	ret = __mlx4_init_one(pdev, id->driver_data);
> +	pci_dev_data = priv->pci_dev_data;
> +	ret = __mlx4_init_one(pdev, pci_dev_data);
>
>   	return ret ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
>   }
[...]

WBR, Sergei