Hi, This is the fifth version of a patchset to add the DMA APIs necessary to map and unmap a PCI device's BAR to and from another PCI device's IOVA domain. This enables PCI peer-to-peer traffic on x86 platforms where an IOMMU is enabled (this requires that peer-to-peer traffic be supported by the underlying chipset as well, of course). Thanks, Will v5: - moved topology and ACS checks into a separate pci_peer_traffic_supported() API, which determines whether PCI peer- to-peer traffic may work based on language in the PCI and PCI Express specifications (excerpts included in comments) - added CONFIG_HAS_DMA_P2P guards to x86 PCI no-mmu implementation of map_peer_resource - modified a few patch descriptions for style v4: http://www.spinics.net/lists/linux-pci/msg43136.html - added HAS_DMA_P2P Kconfig option to guard new APIs, which are only supported on x86 with this patch series - added a new dma_peer_addr_t type to handle future platform support where the dma_peer_addr_t needs to have the same width as the bus address, which can be wider than the dma_addr_t returned by other DMA APIs - added a new dma_peer_mapping_error() and associated PCI wrapper to detect errors returned via dma_map_peer_resource() API and its PCI wrapper - modified the interface of the new API to explicitly take the peer device as an argument - renamed the (un)map_resource APIs to (un)map_peer_resource, since they directly receive a 'peer' argument now - modified the new PCI interface to take the BAR index instead of the actual struct resource - modified the pci-nommu implementation to perform topology and ACS checks before allowing - modified both the AMD and Intel IOMMU implementations to require that both devices be behind the same host bridge - exposed a couple of preexisting PCI utility functions to aid in the topology checks for all of the x86 implementations v3: http://www.spinics.net/lists/linux-pci/msg41703.html - changed dma_map_resource() to BUG() if the map_resource DMA op is not provided, instead of returning 0 - updated documentation to remove requirement to check for 0 return value as an error - remove const keyword from struct dma_map_ops in new DMA APIs for consistency with other APIs v2: http://www.spinics.net/lists/linux-pci/msg41192.html - added documentation for the new DMA APIs - fixed physical-to-bus address conversion in the nommu implementation v1: http://www.spinics.net/lists/linux-pci/msg40747.html Will Davis (13): lib/Kconfig: add HAS_DMA_P2P for peer-to-peer support linux/types.h: Add dma_peer_addr_t type dma-debug: add checking for map/unmap_peer_resource DMA-API: Introduce dma_(un)map_peer_resource dma-mapping: pci: add pci_(un)map_peer_resource DMA-API: Add peer resource mapping documentation PCI: Export pci_find_host_bridge() PCI: Add pci_find_common_upstream_dev() PCI: Add pci_peer_traffic_supported() iommu/amd: Implement (un)map_peer_resource iommu/vt-d: implement (un)map_peer_resource x86: add pci-nommu implementation of map_peer_resource x86: declare support for DMA P2P Documentation/DMA-API-HOWTO.txt | 69 ++++++++++++++++++++++ Documentation/DMA-API.txt | 38 ++++++++++-- arch/x86/Kconfig | 1 + arch/x86/include/asm/dma-mapping.h | 18 +++++- arch/x86/kernel/pci-nommu.c | 36 ++++++++++++ drivers/iommu/amd_iommu.c | 99 +++++++++++++++++++++++++++----- drivers/iommu/intel-iommu.c | 38 ++++++++++++ drivers/pci/host-bridge.c | 19 +----- drivers/pci/pci.c | 99 ++++++++++++++++++++++++++++++++ drivers/pci/search.c | 25 ++++++++ include/asm-generic/dma-mapping-common.h | 43 ++++++++++++++ include/asm-generic/pci-dma-compat.h | 23 ++++++++ include/linux/dma-debug.h | 39 ++++++++++++- include/linux/dma-mapping.h | 12 ++++ include/linux/pci.h | 12 ++++ include/linux/types.h | 13 ++++- lib/Kconfig | 5 ++ lib/dma-debug.c | 86 ++++++++++++++++++++++++++- 18 files changed, 633 insertions(+), 42 deletions(-) -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
