This series introduces a way for PCI resource allocator to force MMIO BARs not to share PAGE_SIZE. This would make sense to VFIO driver. Because current VFIO implementation disallows to mmap sub-page(size < PAGE_SIZE) MMIO BARs which may share the same page with other BARs for security reasons. Thus, we have to handle mmio access to these BARs in QEMU emulation rather than in guest which will cause some performance loss. In our solution, we try to make use of the existing code path of resource_alignment kernel parameter and add a macro to set default alignment for it. Thus we can define this macro by default on some archs which may easily hit the performance issue because of their 64K page. In this series, patch 1 fixes a bug related to bridge window size/alignment caculating; patch 2,3 add support for setting default alignment of all MMIO BAR. Changelog v10: - Introduce an arch-specific function to set default alignment for all PCI devices instead of using macro - Fix some minor comment issues - Code style improvements Changelog v9: - Add a patch to fix for caculating bridge window's size and alignment - Remove an unrelated patch - Rework the patch that fix bug that reassign resources's alignment by changing its size Changelog v8: - Rebased against v4.10-rc4 - Rework the patch 2 - Change the commit log of patch 1 Changelog v7: - Rebased against v4.9-rc2 - Drop two merged patches - Rework the patch which fix a bug that resources's size is changed when using resource_alignment - Add a patch that fix a bug for IOV BARs when using resource_alignment Changelog v6: - Remove the option "noresize@" of resource_alignment Changelog v5: - Rebased against v4.8-rc6 - Drop the patch that forbidding disable memory decoding in pci_reassigndev_resource_alignment() Changelog v4: - Rebased against v4.8-rc1 - Drop one irrelevant patch - Drop the patch that adding wildcard to resource_alignment to enforce the alignment of all MMIO BARs to be at least PAGE_SIZE - Change the format of option "noresize" of resource_alignment - Code style improvements Changelog v3: - Ignore enforced alignment to fixed BARs - Fix issue that disabling memory decoding when reassigning the alignment - Only enable default alignment on PowerNV platform Changelog v2: - Ignore enforced alignment to VF BARs on pci_reassigndev_resource_alignment() Yongji Xie (4): PCI: A fix for caculating bridge window's size and alignment PCI: Add pcibios_default_alignment() for arch-specific alignment control powerpc/powernv: Override pcibios_default_alignment() to force PCI devices to be page aligned PCI: Don't extend device's size when using default alignment for all devices arch/powerpc/include/asm/machdep.h | 2 ++ arch/powerpc/kernel/pci-common.c | 8 ++++++ arch/powerpc/platforms/powernv/pci-ioda.c | 7 +++++ drivers/pci/pci.c | 44 +++++++++++++++++++++-------- drivers/pci/setup-bus.c | 4 +-- 5 files changed, 51 insertions(+), 14 deletions(-) -- 1.7.9.5
