From 6d4f343f84993eb0d5864c0823dc9babd171a33a Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 4 Sep 2008 19:18:02 +0200 Subject: [PATCH] AMD IOMMU: align alloc_coherent addresses properly The API definition for dma_alloc_coherent states that the bus address has to be aligned to the next power of 2 boundary greater than the allocation size. This is violated by AMD IOMMU so far and this patch fixes it. Signed-off-by: Joerg Roedel Signed-off-by: Ingo Molnar --- arch/x86/kernel/amd_iommu.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index d743aa0adcc..15792ed082e 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -383,7 +383,8 @@ static unsigned long dma_mask_to_pages(unsigned long mask) */ static unsigned long dma_ops_alloc_addresses(struct device *dev, struct dma_ops_domain *dom, - unsigned int pages) + unsigned int pages, + unsigned long align_mask) { unsigned long limit = dma_mask_to_pages(*dev->dma_mask); unsigned long address; @@ -400,10 +401,10 @@ static unsigned long dma_ops_alloc_addresses(struct device *dev, } address = iommu_area_alloc(dom->bitmap, limit, dom->next_bit, pages, - 0 , boundary_size, 0); + 0 , boundary_size, align_mask); if (address == -1) { address = iommu_area_alloc(dom->bitmap, limit, 0, pages, - 0, boundary_size, 0); + 0, boundary_size, align_mask); dom->need_flush = true; } @@ -787,17 +788,22 @@ static dma_addr_t __map_single(struct device *dev, struct dma_ops_domain *dma_dom, phys_addr_t paddr, size_t size, - int dir) + int dir, + bool align) { dma_addr_t offset = paddr & ~PAGE_MASK; dma_addr_t address, start; unsigned int pages; + unsigned long align_mask = 0; int i; pages = iommu_num_pages(paddr, size); paddr &= PAGE_MASK; - address = dma_ops_alloc_addresses(dev, dma_dom, pages); + if (align) + align_mask = (1UL << get_order(size)) - 1; + + address = dma_ops_alloc_addresses(dev, dma_dom, pages, align_mask); if (unlikely(address == bad_dma_address)) goto out; @@ -872,7 +878,7 @@ static dma_addr_t map_single(struct device *dev, phys_addr_t paddr, return (dma_addr_t)paddr; spin_lock_irqsave(&domain->lock, flags); - addr = __map_single(dev, iommu, domain->priv, paddr, size, dir); + addr = __map_single(dev, iommu, domain->priv, paddr, size, dir, false); if (addr == bad_dma_address) goto out; @@ -959,7 +965,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist, paddr = sg_phys(s); s->dma_address = __map_single(dev, iommu, domain->priv, - paddr, s->length, dir); + paddr, s->length, dir, false); if (s->dma_address) { s->dma_length = s->length; @@ -1053,7 +1059,7 @@ static void *alloc_coherent(struct device *dev, size_t size, spin_lock_irqsave(&domain->lock, flags); *dma_addr = __map_single(dev, iommu, domain->priv, paddr, - size, DMA_BIDIRECTIONAL); + size, DMA_BIDIRECTIONAL, true); if (*dma_addr == bad_dma_address) { free_pages((unsigned long)virt_addr, get_order(size)); -- 2.41.1