From 602d9858f07c72eab64f5f00e2fae55f9902cfbe Mon Sep 17 00:00:00 2001 From: Nikita Yushchenko Date: Wed, 11 Jan 2017 21:56:31 +0300 Subject: [PATCH] swiotlb: ensure that page-sized mappings are page-aligned Some drivers do depend on page mappings to be page aligned. Swiotlb already enforces such alignment for mappings greater than page, extend that to page-sized mappings as well. Without this fix, nvme hits BUG() in nvme_setup_prps(), because that routine assumes page-aligned mappings. Signed-off-by: Nikita Yushchenko Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Konrad Rzeszutek Wilk --- lib/swiotlb.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 975b8fc4f1e1..a8d74a733a38 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -483,11 +483,11 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); /* - * For mappings greater than a page, we limit the stride (and - * hence alignment) to a page size. + * For mappings greater than or equal to a page, we limit the stride + * (and hence alignment) to a page size. */ nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - if (size > PAGE_SIZE) + if (size >= PAGE_SIZE) stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); else stride = 1; -- 2.20.1