From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Helgaas Subject: Re: [PATCH v3 3/7] dma-mapping: pci: add pci_(un)map_resource Date: Wed, 1 Jul 2015 13:31:27 -0500 Message-ID: <20150701183127.GD13409@google.com> References: <1432919686-32306-1-git-send-email-wdavis@nvidia.com> <1432919686-32306-4-git-send-email-wdavis@nvidia.com> <20150701160606.GA13409@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20150701160606.GA13409-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: wdavis-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org Cc: Dave Jiang , John Hubbard , Jonathan Corbet , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Jerome Glisse , linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Terence Ripperda , "David S. Miller" List-Id: iommu@lists.linux-foundation.org On Wed, Jul 01, 2015 at 11:06:06AM -0500, Bjorn Helgaas wrote: > On Fri, May 29, 2015 at 12:14:42PM -0500, wdavis-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org wrote: > > From: Will Davis > > > > Simply route these through to the new dma_(un)map_resource APIs. > > > > Signed-off-by: Will Davis > > Reviewed-by: Terence Ripperda > > Reviewed-by: John Hubbard > > --- > > include/asm-generic/pci-dma-compat.h | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/include/asm-generic/pci-dma-compat.h b/include/asm-generic/pci-dma-compat.h > > index c110843..ac4a4ad 100644 > > --- a/include/asm-generic/pci-dma-compat.h > > +++ b/include/asm-generic/pci-dma-compat.h > > @@ -61,6 +61,20 @@ pci_unmap_page(struct pci_dev *hwdev, dma_addr_t dma_address, > > dma_unmap_page(hwdev == NULL ? NULL : &hwdev->dev, dma_address, size, (enum dma_data_direction)direction); > > } > > > > +static inline dma_addr_t > > +pci_map_resource(struct pci_dev *hwdev, struct resource *resource, > > + unsigned long offset, size_t size, int direction) > > After 3a9ad0b4fdcd ("PCI: Add pci_bus_addr_t"), which will appear in > v4.2-rc1, there is a pci_bus_addr_t, and I think you need that instead > of dma_addr_t. > > http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3a9ad0b4fdcd This wasn't a very good response, sorry. I don't think just changing dma_addr_t to pci_bus_addr_t is a good resolution. Isn't there an implicit assumption here that either you're using an IOMMU driver that always returns bus addresses that fit in a dma_addr_t, or you're not using an IOMMU and dma_addr_t is big enough for any bus address? What happens on a system with 64-bit PCI bus addresses, 32-bit dma_addr_t, and no IOMMU? Would this return failure somehow? > > +{ > > + return dma_map_resource(hwdev == NULL ? NULL : &hwdev->dev, resource, offset, size, (enum dma_data_direction)direction); > > +} > > + > > +static inline void > > +pci_unmap_resource(struct pci_dev *hwdev, dma_addr_t dma_address, size_t size, > > + int direction) > > +{ > > + dma_unmap_resource(hwdev == NULL ? NULL : &hwdev->dev, dma_address, size, (enum dma_data_direction)direction); > > +} > > + > > static inline int > > pci_map_sg(struct pci_dev *hwdev, struct scatterlist *sg, > > int nents, int direction) > > -- > > 2.4.0 > >