vfio: Provide module option to disable vfio_iommu_type1 hugepage support (5c6c2b21) · Commits · 戴 / test

Add a module option to vfio_iommu_type1 to disable IOMMU hugepage support. This causes iommu_map to only be called with single page mappings, disabling the IOMMU driver's ability to use hugepages. This option can be enabled by loading vfio_iommu_type1 with disable_hugepages=1 or dynamically through sysfs. If enabled dynamically, only new mappings are restricted. Signed-off-by:

Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/vfio_iommu_type1.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -48,6 +48,12 @@ module_param_named(allow_unsafe_interrupts,
		MODULE_PARM_DESC(allow_unsafe_interrupts,
		"Enable VFIO IOMMU support for on platforms without interrupt remapping support.");

		static bool disable_hugepages;
		module_param_named(disable_hugepages,
		disable_hugepages, bool, S_IRUGO \| S_IWUSR);
		MODULE_PARM_DESC(disable_hugepages,
		"Disable VFIO IOMMU support for IOMMU hugepages.");

		struct vfio_iommu {
		struct iommu_domain *domain;
		struct mutex lock;
		@@ -270,6 +276,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
		return -ENOMEM;
		}

		if (unlikely(disable_hugepages)) {
		vfio_lock_acct(1);
		return 1;
		}

		/* Lock all the consecutive pages from pfn_base */
		for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
		unsigned long pfn = 0;

Admin message