[PATCH 1/7] pci: export PCI BAR size-reading functions

[Christian König]

Am 11.12.20 um 01:55 schrieb Darren Salt:
> This is to assist driver modules which do BAR resizing.
>
> Signed-off-by: Darren Salt <devspam at moreofthesa.me.uk>
> ---
>   drivers/pci/pci.c   | 2 ++
>   drivers/pci/pci.h   | 2 --
>   include/linux/pci.h | 4 ++++
>   3 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index e578d34095e9..3f6042d9ad83 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -3579,6 +3579,7 @@ u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
>   	pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
>   	return (cap & PCI_REBAR_CAP_SIZES) >> 4;
>   }
> +EXPORT_SYMBOL(pci_rebar_get_possible_sizes);
>   
>   /**
>    * pci_rebar_get_current_size - get the current size of a BAR
> @@ -3600,6 +3601,7 @@ int pci_rebar_get_current_size(struct pci_dev *pdev, int bar)
>   	pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
>   	return (ctrl & PCI_REBAR_CTRL_BAR_SIZE) >> PCI_REBAR_CTRL_BAR_SHIFT;
>   }
> +EXPORT_SYMBOL(pci_rebar_get_current_size);

This is unnecessary. You can just look at the resource size instead 
which is also more defensive regarding problems/errors.

Christian.

>   
>   /**
>    * pci_rebar_set_size - set a new size for a BAR
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index f86cae9aa1f4..8373d94414e9 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -608,8 +608,6 @@ int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
>   			  struct resource *res);
>   #endif
>   
> -u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar);
> -int pci_rebar_get_current_size(struct pci_dev *pdev, int bar);
>   int pci_rebar_set_size(struct pci_dev *pdev, int bar, int size);
>   static inline u64 pci_rebar_size_to_bytes(int size)
>   {
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 22207a79762c..5aa035622741 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1226,7 +1226,11 @@ void pci_update_resource(struct pci_dev *dev, int resno);
>   int __must_check pci_assign_resource(struct pci_dev *dev, int i);
>   int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align);
>   void pci_release_resource(struct pci_dev *dev, int resno);
> +
> +u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar);
> +int pci_rebar_get_current_size(struct pci_dev *pdev, int bar);
>   int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size);
> +
>   int pci_select_bars(struct pci_dev *dev, unsigned long flags);
>   bool pci_device_is_present(struct pci_dev *pdev);
>   void pci_ignore_hotplug(struct pci_dev *dev);