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 <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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 @@ struct dmar_domain *get_valid_domain_for_dev(struct device *dev)
}
/* 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);