From aa3de9c05051ac26355276944789217040e38207 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Thu, 10 Nov 2011 11:32:29 +0200 Subject: [PATCH] iommu/amd: announce supported page sizes Let the IOMMU core know we support arbitrary page sizes (as long as they're an order of 4KiB). This way the IOMMU core will retain the existing behavior we're used to; it will let us map regions that: - their size is an order of 4KiB - they are naturally aligned Signed-off-by: Ohad Ben-Cohen Cc: Joerg Roedel Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) 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, }; /*****************************************************************************