On Sun, Dec 10, 2017 at 12:43:48AM +0100, Heiner Kallweit wrote:
> Introduce a device-managed version of pci_set_mwi. First user is the
> Realtek r8169 driver.
>
> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
With the subject and changelog as follows and the code reordering below,
PCI: Add pcim_set_mwi(), a device-managed pci_set_mwi()
Add pcim_set_mwi(), a device-managed version of pci_set_mwi(). First user
is the Realtek r8169 driver.
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
With these changes, feel free to merge with the series via the netdev
tree.
> ---
> drivers/pci/pci.c | 29 +++++++++++++++++++++++++++++
> include/linux/pci.h | 1 +
> 2 files changed, 30 insertions(+)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 4a7c6864f..fc57c378d 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -1458,6 +1458,7 @@ struct pci_devres {
> unsigned int pinned:1;
> unsigned int orig_intx:1;
> unsigned int restore_intx:1;
> + unsigned int mwi:1;
> u32 region_mask;
> };
>
> @@ -1476,6 +1477,9 @@ static void pcim_release(struct device *gendev, void *res)
> if (this->region_mask & (1 << i))
> pci_release_region(dev, i);
>
> + if (this->mwi)
> + pci_clear_mwi(dev);
> +
> if (this->restore_intx)
> pci_intx(dev, this->orig_intx);
>
> @@ -3760,6 +3764,31 @@ int pci_set_mwi(struct pci_dev *dev)
> }
> EXPORT_SYMBOL(pci_set_mwi);
>
> +/**
> + * pcim_set_mwi - Managed pci_set_mwi()
> + * @dev: 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)
> +{
> + struct pci_devres *dr;
> + int ret;
> +
> + ret = pci_set_mwi(dev);
> + if (ret)
> + return ret;
> +
> + dr = find_pci_dr(dev);
> + if (dr)
> + dr->mwi = 1;
> +
> + return 0;
I would rather look up the pci_devres first, e.g.,
dr = find_pci_dr(dev);
if (!dr)
return -ENOMEM;
dr->mwi = 1;
return pci_set_mwi(dev);
That way we won't enable MWI and be unable to disable it at release-time.
> +}
> +EXPORT_SYMBOL(pcim_set_mwi);
> +
> /**
> * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
> * @dev: the PCI device for which MWI is enabled
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 978aad784..0a7ac863a 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1064,6 +1064,7 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state);
> int pci_set_cacheline_size(struct pci_dev *dev);
> #define HAVE_PCI_SET_MWI
> int __must_check pci_set_mwi(struct pci_dev *dev);
> +int __must_check pcim_set_mwi(struct pci_dev *dev);
> int pci_try_set_mwi(struct pci_dev *dev);
> void pci_clear_mwi(struct pci_dev *dev);
> void pci_intx(struct pci_dev *dev, int enable);
> --
> 2.15.1
>
>
