diff options
Diffstat (limited to 'drivers/iommu/amd_iommu.c')
| -rw-r--r-- | drivers/iommu/amd_iommu.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index a3b7072e86e2..341573821864 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -41,6 +41,24 @@ #define LOOP_TIMEOUT 100000 +/* + * This bitmap is used to advertise the page sizes our hardware support + * to the IOMMU core, which will then use this information to split + * physically contiguous memory regions it is mapping into page sizes + * that we support. + * + * Traditionally the IOMMU core just handed us the mappings directly, + * after making sure the size is an order of a 4KiB page and that the + * mapping has natural alignment. + * + * To retain this behavior, we currently advertise that we support + * all page sizes that are an order of 4KiB. + * + * If at some point we'd like to utilize the IOMMU core's new behavior, + * we could change this to advertise the real page sizes we support. + */ +#define AMD_IOMMU_PGSIZES (~0xFFFUL) + static DEFINE_RWLOCK(amd_iommu_devtable_lock); /* A list of preallocated protection domains */ @@ -2779,6 +2797,7 @@ static struct iommu_ops amd_iommu_ops = { .unmap = amd_iommu_unmap, .iova_to_phys = amd_iommu_iova_to_phys, .domain_has_cap = amd_iommu_domain_has_cap, + .pgsize_bitmap = AMD_IOMMU_PGSIZES, }; /***************************************************************************** |