[+cc Christoph, Thomas, Alexander, in case you're interested]
[+cc Jonathan, Kurt, Logan: vmd.c and switchtec.c use managed resources
and pci_alloc_irq_vectors()]
On Fri, Feb 26, 2021 at 11:50:53PM +0800, Dejin Zheng wrote:
> Introduce pcim_alloc_irq_vectors(), a device-managed version of
> pci_alloc_irq_vectors(). Introducing this function can simplify
> the error handling path in many drivers.
>
> And use pci_free_irq_vectors() to replace some code in pcim_release(),
> they are equivalent, and no functional change. It is more explicit
> that pcim_alloc_irq_vectors() is a device-managed function.
>
> Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Let me know if you'd like me to take the series.
> ---
> v4 -> v5:
> - Remove the check of enable device in pcim_alloc_irq_vectors()
> and make it as a static line function.
> v3 -> v4:
> - No change
> v2 -> v3:
> - Add some commit comments for replace some codes in
> pcim_release() by pci_free_irq_vectors().
> v1 -> v2:
> - Use pci_free_irq_vectors() to replace some code in
> pcim_release().
> - Modify some commit messages.
>
> drivers/pci/pci.c | 5 +----
> include/linux/pci.h | 24 ++++++++++++++++++++++++
> 2 files changed, 25 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 16a17215f633..fecfdc0add2f 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -1969,10 +1969,7 @@ static void pcim_release(struct device *gendev, void *res)
> struct pci_devres *this = res;
> int i;
>
> - if (dev->msi_enabled)
> - pci_disable_msi(dev);
> - if (dev->msix_enabled)
> - pci_disable_msix(dev);
> + pci_free_irq_vectors(dev);
>
> for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
> if (this->region_mask & (1 << i))
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 86c799c97b77..5cafd7d65fd7 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1818,6 +1818,30 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> NULL);
> }
>
> +/**
> + * pcim_alloc_irq_vectors - a device-managed pci_alloc_irq_vectors()
> + * @dev: PCI device to operate on
> + * @min_vecs: minimum number of vectors required (must be >= 1)
> + * @max_vecs: maximum (desired) number of vectors
> + * @flags: flags or quirks for the allocation
> + *
> + * Return the number of vectors allocated, (which might be smaller than
> + * @max_vecs) if successful, or a negative error code on error. If less
> + * than @min_vecs interrupt vectors are available for @dev the function
> + * will fail with -ENOSPC.
> + *
> + * It depends on calling pcim_enable_device() to make IRQ resources
> + * manageable.
> + */
> +static inline int
> +pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> + unsigned int max_vecs, unsigned int flags)
> +{
> + if (!pci_is_managed(dev))
> + return -EINVAL;
> + return pci_alloc_irq_vectors(dev, min_vecs, max_vecs, flags);
> +}
> +
> /* Include architecture-dependent settings and functions */
>
> #include <asm/pci.h>
> --
> 2.25.0
>
