From 633d5fce78a61e8727674467944939f55b0bcfab Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Thu, 11 Jun 2020 12:20:28 -0700 Subject: [PATCH] dma-direct: always align allocation size in dma_direct_alloc_pages() dma_alloc_contiguous() does size >> PAGE_SHIFT and set_memory_decrypted() works at page granularity. It's necessary to page align the allocation size in dma_direct_alloc_pages() for consistent behavior. This also fixes an issue when arch_dma_prep_coherent() is called on an unaligned allocation size for dma_alloc_need_uncached() when CONFIG_DMA_DIRECT_REMAP is disabled but CONFIG_ARCH_HAS_DMA_SET_UNCACHED is enabled. Signed-off-by: David Rientjes Signed-off-by: Christoph Hellwig --- kernel/dma/direct.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 30c41b57acd9..c93e3c8e3d01 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -112,11 +112,12 @@ static inline bool dma_should_free_from_pool(struct device *dev, static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, gfp_t gfp, unsigned long attrs) { - size_t alloc_size = PAGE_ALIGN(size); int node = dev_to_node(dev); struct page *page = NULL; u64 phys_limit; + WARN_ON_ONCE(!PAGE_ALIGNED(size)); + if (attrs & DMA_ATTR_NO_WARN) gfp |= __GFP_NOWARN; @@ -124,14 +125,14 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, gfp &= ~__GFP_ZERO; gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, &phys_limit); - page = dma_alloc_contiguous(dev, alloc_size, gfp); + page = dma_alloc_contiguous(dev, size, gfp); if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { - dma_free_contiguous(dev, page, alloc_size); + dma_free_contiguous(dev, page, size); page = NULL; } again: if (!page) - page = alloc_pages_node(node, gfp, get_order(alloc_size)); + page = alloc_pages_node(node, gfp, get_order(size)); if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { dma_free_contiguous(dev, page, size); page = NULL; @@ -158,8 +159,10 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, struct page *page; void *ret; + size = PAGE_ALIGN(size); + if (dma_should_alloc_from_pool(dev, gfp, attrs)) { - ret = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &page, gfp); + ret = dma_alloc_from_pool(dev, size, &page, gfp); if (!ret) return NULL; goto done; @@ -183,10 +186,10 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, dma_alloc_need_uncached(dev, attrs)) || (IS_ENABLED(CONFIG_DMA_REMAP) && PageHighMem(page))) { /* remove any dirty cache lines on the kernel alias */ - arch_dma_prep_coherent(page, PAGE_ALIGN(size)); + arch_dma_prep_coherent(page, size); /* create a coherent mapping */ - ret = dma_common_contiguous_remap(page, PAGE_ALIGN(size), + ret = dma_common_contiguous_remap(page, size, dma_pgprot(dev, PAGE_KERNEL, attrs), __builtin_return_address(0)); if (!ret)