From 9f5f5fb35d2934fe7dc0cb019854a030efd10cd7 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 14 Aug 2008 19:55:16 +0200 Subject: x86, AMD IOMMU: initialize device table properly This patch adds device table initializations which forbids memory accesses for devices per default and disables all page faults. Signed-off-by: Joerg Roedel Signed-off-by: Ingo Molnar --- arch/x86/kernel/amd_iommu_init.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'arch/x86/kernel/amd_iommu_init.c') diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index d9a9da597e79..ceba33811537 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -800,6 +800,21 @@ static int __init init_memory_definitions(struct acpi_table_header *table) return 0; } +/* + * Init the device table to not allow DMA access for devices and + * suppress all page faults + */ +static void init_device_table(void) +{ + u16 devid; + + for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) { + set_dev_entry_bit(devid, DEV_ENTRY_VALID); + set_dev_entry_bit(devid, DEV_ENTRY_TRANSLATION); + set_dev_entry_bit(devid, DEV_ENTRY_NO_PAGE_FAULT); + } +} + /* * This function finally enables all IOMMUs found in the system after * they have been initialized @@ -931,6 +946,9 @@ int __init amd_iommu_init(void) if (amd_iommu_pd_alloc_bitmap == NULL) goto free; + /* init the device table */ + init_device_table(); + /* * let all alias entries point to itself */ -- cgit v1.2.2