Re: [PATCH 07/10] pci: devres: give mwi its own callback

[Bjorn Helgaas <helgaas@kernel.org>]

On Mon, Jan 15, 2024 at 03:46:18PM +0100, Philipp Stanner wrote:
> managing mwi with devres can easily be done with its own callback,
> without the necessity to store any state about it in a device-related
> struct.

s/managing/Managing/

s/mwi/MWI/ since this is an initialism.  Also in subject (but would be
even better if it could mention an actual function name).

> Remove the mwi state from the devres-struct.
> Make the devres-mwi functions set a separate devres-callback.

Wrap to fill 75 columns (or add blank lines if you intend multiple
paragraphs).

s/devres-struct/struct pci_devres/ to make this greppable.

s/the devres-mwi functions/pcim_set_mwi()/ similarly.

> Signed-off-by: Philipp Stanner <pstanner@redhat.com>
> ---
>  drivers/pci/devres.c | 23 +++++++++++------------
>  drivers/pci/pci.h    |  1 -
>  2 files changed, 11 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
> index de8cf6f87dd7..911c2037d9fd 100644
> --- a/drivers/pci/devres.c
> +++ b/drivers/pci/devres.c
> @@ -378,24 +378,26 @@ void __iomem *devm_pci_remap_cfg_resource(struct device *dev,
>  }
>  EXPORT_SYMBOL(devm_pci_remap_cfg_resource);
>  
> +static void __pcim_clear_mwi(void *pdev_raw)
> +{
> +	struct pci_dev *pdev = pdev_raw;
> +
> +	pci_clear_mwi(pdev);
> +}
> +
>  /**
>   * pcim_set_mwi - a device-managed pci_set_mwi()
> - * @dev: the PCI device for which MWI is enabled
> + * @pdev: the PCI device for which MWI is enabled
>   *
>   * Managed pci_set_mwi().
>   *
>   * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
>   */
> -int pcim_set_mwi(struct pci_dev *dev)
> +int pcim_set_mwi(struct pci_dev *pdev)
>  {
> -	struct pci_devres *dr;
> -
> -	dr = find_pci_dr(dev);
> -	if (!dr)
> -		return -ENOMEM;
> +	devm_add_action(&pdev->dev, __pcim_clear_mwi, pdev);
>  
> -	dr->mwi = 1;
> -	return pci_set_mwi(dev);
> +	return pci_set_mwi(pdev);
>  }
>  EXPORT_SYMBOL(pcim_set_mwi);
>  
> @@ -405,9 +407,6 @@ static void pcim_release(struct device *gendev, void *res)
>  	struct pci_dev *dev = to_pci_dev(gendev);
>  	struct pci_devres *this = res;
>  
> -	if (this->mwi)
> -		pci_clear_mwi(dev);
> -
>  	if (this->restore_intx)
>  		pci_intx(dev, this->orig_intx);
>  
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 3d9908a69ebf..667bfdd61d5e 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -811,7 +811,6 @@ static inline pci_power_t mid_pci_get_power_state(struct pci_dev *pdev)
>  struct pci_devres {
>  	unsigned int orig_intx:1;
>  	unsigned int restore_intx:1;
> -	unsigned int mwi:1;
>  };
>  
>  struct pci_devres *find_pci_dr(struct pci_dev *pdev);
> -- 
> 2.43.0
>