From 48b2c937ea37a3bece0094b46450ed5267525289 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 10 Apr 2019 18:14:06 +0200 Subject: [PATCH] iommu/vt-d: Clean up iommu_no_mapping Invert the return value to avoid double negatives, use a bool instead of int as the return value, and reduce some indentation after early returns. Signed-off-by: Christoph Hellwig Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu.c | 47 ++++++++++++++++++++------------------------- 1 file changed, 21 insertions(+), 26 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index c137f0f..46337a4 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3608,45 +3608,40 @@ out: } /* Check if the dev needs to go through non-identity map and unmap process.*/ -static int iommu_no_mapping(struct device *dev) +static bool iommu_need_mapping(struct device *dev) { int found; if (iommu_dummy(dev)) - return 1; + return false; if (!iommu_identity_mapping) - return 0; + return true; found = identity_mapping(dev); if (found) { if (iommu_should_identity_map(dev, 0)) - return 1; - else { - /* - * 32 bit DMA is removed from si_domain and fall back - * to non-identity mapping. - */ - dmar_remove_one_dev_info(dev); - dev_info(dev, "32bit DMA uses non-identity mapping\n"); - return 0; - } + return false; + + /* + * 32 bit DMA is removed from si_domain and fall back to + * non-identity mapping. + */ + dmar_remove_one_dev_info(dev); + dev_info(dev, "32bit DMA uses non-identity mapping\n"); } else { /* * In case of a detached 64 bit DMA device from vm, the device * is put into si_domain for identity mapping. */ - if (iommu_should_identity_map(dev, 0)) { - int ret; - ret = domain_add_dev_info(si_domain, dev); - if (!ret) { - dev_info(dev, "64bit DMA uses identity mapping\n"); - return 1; - } + if (iommu_should_identity_map(dev, 0) && + !domain_add_dev_info(si_domain, dev)) { + dev_info(dev, "64bit DMA uses identity mapping\n"); + return false; } } - return 0; + return true; } static dma_addr_t __intel_map_single(struct device *dev, phys_addr_t paddr, @@ -3662,7 +3657,7 @@ static dma_addr_t __intel_map_single(struct device *dev, phys_addr_t paddr, BUG_ON(dir == DMA_NONE); - if (iommu_no_mapping(dev)) + if (!iommu_need_mapping(dev)) return paddr; domain = get_valid_domain_for_dev(dev); @@ -3733,7 +3728,7 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size) struct intel_iommu *iommu; struct page *freelist; - if (iommu_no_mapping(dev)) + if (!iommu_need_mapping(dev)) return; domain = find_domain(dev); @@ -3784,7 +3779,7 @@ static void *intel_alloc_coherent(struct device *dev, size_t size, size = PAGE_ALIGN(size); order = get_order(size); - if (!iommu_no_mapping(dev)) + if (iommu_need_mapping(dev)) flags &= ~(GFP_DMA | GFP_DMA32); else if (dev->coherent_dma_mask < dma_get_required_mask(dev)) { if (dev->coherent_dma_mask < DMA_BIT_MASK(32)) @@ -3798,7 +3793,7 @@ static void *intel_alloc_coherent(struct device *dev, size_t size, page = dma_alloc_from_contiguous(dev, count, order, flags & __GFP_NOWARN); - if (page && iommu_no_mapping(dev) && + if (page && !iommu_need_mapping(dev) && page_to_phys(page) + size > dev->coherent_dma_mask) { dma_release_from_contiguous(dev, page, count); page = NULL; @@ -3880,7 +3875,7 @@ static int intel_map_sg(struct device *dev, struct scatterlist *sglist, int nele struct intel_iommu *iommu; BUG_ON(dir == DMA_NONE); - if (iommu_no_mapping(dev)) + if (!iommu_need_mapping(dev)) return intel_nontranslate_map_sg(dev, sglist, nelems, dir); domain = get_valid_domain_for_dev(dev); -- 2.7.4