From 2690899d56f2ed0cb6b24a60c02bcbf8c950d35c Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 13 Sep 2024 12:05:02 +0200 Subject: [PATCH] xen/swiotlb: add alignment check for dma buffers [ Upstream commit 9f40ec84a7976d95c34e7cc070939deb103652b0 ] When checking a memory buffer to be consecutive in machine memory, the alignment needs to be checked, too. Failing to do so might result in DMA memory not being aligned according to its requested size, leading to error messages like: 4xxx 0000:2b:00.0: enabling device (0140 -> 0142) 4xxx 0000:2b:00.0: Ring address not aligned 4xxx 0000:2b:00.0: Failed to initialise service qat_crypto 4xxx 0000:2b:00.0: Resetting device qat_dev0 4xxx: probe of 0000:2b:00.0 failed with error -14 Fixes: 9435cce87950 ("xen/swiotlb: Add support for 64KB page granularity") Signed-off-by: Juergen Gross Reviewed-by: Stefano Stabellini Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin (cherry picked from commit 66c845af6613a62f08d1425054526cc294842914) Signed-off-by: Vegard Nossum Signed-off-by: Harshit Mogalapalli --- drivers/xen/swiotlb-xen.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index a950f9b377b1..2863731b1fae 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -112,9 +112,15 @@ static inline int range_straddles_page_boundary(phys_addr_t p, size_t size) { unsigned long next_bfn, xen_pfn = XEN_PFN_DOWN(p); unsigned int i, nr_pages = XEN_PFN_UP(xen_offset_in_page(p) + size); + phys_addr_t algn = 1ULL << (get_order(size) + PAGE_SHIFT); next_bfn = pfn_to_bfn(xen_pfn); + /* If buffer is physically aligned, ensure DMA alignment. */ + if (IS_ALIGNED(p, algn) && + !IS_ALIGNED((phys_addr_t)next_bfn << XEN_PAGE_SHIFT, algn)) + return 1; + for (i = 1; i < nr_pages; i++) if (pfn_to_bfn(++xen_pfn) != ++next_bfn) return 1;