here is the 2nd version of providing an DMA API for s390. There are some attempts to unify the dma ops (Christoph) as well as some attempts to make virtio use the dma API (Andy). At kernel summit we concluded that we want to use the same code on all platforms, whereever possible, so having a dummy dma_op might be the easiest solution to keep virtio-ccw as similar as possible to virtio-pci.Together with a fixed up patch set from Andy Lutomirski this seems to work. We will also need a fixup for powerc and QEMU changes to make virtio work with iommu on power and x86. TODO: - future add-on patches to also fold in x86 no iommu - dma_mask - checking? - make compilation of dma-noop dependent on something v1->v2: - initial testing - always use dma_noop_ops if device has no private dma_ops - get rid of setup in virtio_ccw,kvm_virtio - set CONFIG_HAS_DMA(ATTRS) for virtio (fixes compile for !PCI) - rename s390_dma_ops to s390_pci_dma_ops Christian Borntraeger (3): Provide simple noop dma ops alpha: use common noop dma ops s390/dma: Allow per device dma ops arch/alpha/kernel/pci-noop.c | 46 ++-------------------- arch/s390/Kconfig | 3 +- arch/s390/include/asm/device.h | 6 ++- arch/s390/include/asm/dma-mapping.h | 6 ++- arch/s390/pci/pci.c | 1 + arch/s390/pci/pci_dma.c | 4 +- include/linux/dma-mapping.h | 2 + lib/Makefile | 2 +- lib/dma-noop.c | 77 +++++++++++++++++++++++++++++++++++++ 9 files changed, 98 insertions(+), 49 deletions(-) create mode 100644 lib/dma-noop.c -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
