v3 Set: https://lore.kernel.org/linux-iommu/20200113181742.GA27623@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#t v2 Set: https://lore.kernel.org/linux-iommu/1578580256-3483-1-git-send-email-jonathan.derrick@xxxxxxxxx/T/#t v1 Set: https://lore.kernel.org/linux-iommu/20200107134125.GD30750@xxxxxxxxxx/T/#t VMD currently works with VT-d enabled by pointing DMA and IOMMU actions at the VMD endpoint. The problem with this approach is that the VMD endpoint's device-specific attributes, such as the DMA Mask Bits, are used instead of the child device's attributes. This set cleans up VMD by removing the override that redirects DMA map operations to the VMD endpoint. Instead it introduces a new DMA alias mechanism into the existing DMA alias infrastructure. This new DMA alias mechanism allows an architecture-specific pci_real_dma_dev() function to provide a pointer from a pci_dev to its PCI DMA device, where by default it returns the original pci_dev. In addition, this set removes the sanity check that was added to prevent assigning VMD child devices. By using the DMA alias mechanism, all child devices are assigned the same IOMMU group as the VMD endpoint. This removes the need for restricting VMD child devices from assignment, as the whole group would have to be assigned, requiring unbinding the VMD driver and removing the child device domain. v1 added a pointer in struct pci_dev that pointed to the DMA alias' struct pci_dev and did the necessary DMA alias and IOMMU modifications. v2 introduced a new weak function to reference the 'Direct DMA Alias', and removed the need to add a pointer in struct device or pci_dev. Weak functions are generally frowned upon when it's a single architecture implementation, so I am open to alternatives. v3 referenced the pci_dev rather than the struct device for the PCI 'Direct DMA Alias' (pci_direct_dma_alias()). This revision also allowed pci_for_each_dma_alias() to call any DMA aliases for the Direct DMA alias device, though I don't expect the VMD endpoint to need intra-bus DMA aliases. v4 changes the 'Direct DMA Alias' to instead refer to the 'Real DMA Dev', which either returns the PCI device itself or the PCI DMA device. Changes from v3: Uses pci_real_dma_dev() instead of pci_direct_dma_alias() Split IOMMU enabling, IOMMU VMD sanity check and VMD dma_map_ops cleanup into three patches Changes from v2: Uses struct pci_dev for PCI Device 'Direct DMA aliasing' (pci_direct_dma_alias) Allows pci_for_each_dma_alias to iterate over the alias mask of the 'Direct DMA alias' Changes from v1: Removed 1/5 & 2/5 misc fix patches that were merged Uses Christoph's staging/cleanup patches Introduce weak function rather than including pointer in struct device or pci_dev. Based on Bjorn's next: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=next Christoph Hellwig (2): x86/PCI: Add a to_pci_sysdata helper x86/PCI: Remove X86_DEV_DMA_OPS Jon Derrick (5): x86/PCI: Expose VMD's PCI Device in pci_sysdata PCI: Introduce pci_real_dma_dev() iommu/vt-d: Use pci_real_dma_dev() for mapping iommu/vt-d: Remove VMD child device sanity check PCI: vmd: Stop overriding dma_map_ops arch/x86/Kconfig | 3 - arch/x86/include/asm/device.h | 10 --- arch/x86/include/asm/pci.h | 31 ++++----- arch/x86/pci/common.c | 48 +++---------- drivers/iommu/intel-iommu.c | 15 ++-- drivers/pci/controller/Kconfig | 1 - drivers/pci/controller/vmd.c | 152 +---------------------------------------- drivers/pci/pci.c | 19 +++++- drivers/pci/search.c | 6 ++ include/linux/pci.h | 1 + 10 files changed, 58 insertions(+), 228 deletions(-) -- 1.8.3.1
