| Message ID | 1442337067-22964-11-git-send-email-wdavis@nvidia.com |
|---|---|
| State | Changes Requested |
| Headers | show |
On Tue, Sep 15, 2015 at 12:10:55PM -0500, Will Davis wrote: > Add helper to convert a struct resource to a peer DMA address. > > Signed-off-by: Will Davis <wdavis@nvidia.com> > --- > include/linux/pci.h | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/include/linux/pci.h b/include/linux/pci.h > index db0cb51..2a9deff 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1508,6 +1508,22 @@ static inline void pci_resource_to_user(const struct pci_dev *dev, int bar, > } > #endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */ > > +#ifdef CONFIG_HAS_DMA_P2P > +static inline bool pci_resource_to_peer(struct pci_dev *dev, I'm not really a fan of functions that return bool unless the function name is obviously a predicate. So in this case, I'd return 0 or a negative errno. > + struct pci_dev *peer, > + struct resource *res, > + dma_peer_addr_t *peer_addr) { > + if (pci_peer_traffic_supported(dev, peer)) { > + struct pci_bus_region region; > + > + pcibios_resource_to_bus(dev->bus, ®ion, res); > + *peer_addr = region.start; > + return true; > + } > + > + return false; It's trivial, but I'd structure it like this, which is sort of the typical "return errors early" pattern, and reduces indentation of the mainline path: if (!pci_peer_traffic_supported(dev, peer)) return -EINVAL; pcibios_resource_to_bus(dev->bus, ®ion, res); *peer_addr = region.start; return 0; > +} > +#endif /* CONFIG_HAS_DMA_P2P */ > > /* > * The world is not perfect and supplies us with broken PCI devices. > -- > 2.5.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/pci.h b/include/linux/pci.h index db0cb51..2a9deff 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1508,6 +1508,22 @@ static inline void pci_resource_to_user(const struct pci_dev *dev, int bar, } #endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */ +#ifdef CONFIG_HAS_DMA_P2P +static inline bool pci_resource_to_peer(struct pci_dev *dev, + struct pci_dev *peer, + struct resource *res, + dma_peer_addr_t *peer_addr) { + if (pci_peer_traffic_supported(dev, peer)) { + struct pci_bus_region region; + + pcibios_resource_to_bus(dev->bus, ®ion, res); + *peer_addr = region.start; + return true; + } + + return false; +} +#endif /* CONFIG_HAS_DMA_P2P */ /* * The world is not perfect and supplies us with broken PCI devices.
Add helper to convert a struct resource to a peer DMA address. Signed-off-by: Will Davis <wdavis@nvidia.com> --- include/linux/pci.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)