Merge tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - fix an integer overflow in the coherent pool (Kevin Grandemange)

 - provide support for in-place uncached remapping and use that for
   openrisc

 - fix the arm coherent allocator to take the bus limit into account

* tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping:
  ARM/dma-mapping: merge __dma_supported into arm_dma_supported
  ARM/dma-mapping: take the bus limit into account in __dma_alloc
  ARM/dma-mapping: remove get_coherent_dma_mask
  openrisc: use the generic in-place uncached DMA allocator
  dma-direct: provide a arch_dma_clear_uncached hook
  dma-direct: make uncached_kernel_address more general
  dma-direct: consolidate the error handling in dma_direct_alloc_pages
  dma-direct: remove the cached_kernel_address hook
  dma-coherent: fix integer overflow in the reserved-memory dma allocation

2 files changed, 18 insertions, 60 deletions

diff --git a/arch/arm/include/asm/dma-iommu.h b/arch/arm/include/asm/dma-iommu.h
index 772f48ef84b7..86405cc81385 100644
--- a/arch/arm/include/asm/dma-iommu.h
+++ b/arch/arm/include/asm/dma-iommu.h
@@ -33,7 +33,5 @@ int arm_iommu_attach_device(struct device *dev,
 					struct dma_iommu_mapping *mapping);
 void arm_iommu_detach_device(struct device *dev);
 
-int arm_dma_supported(struct device *dev, u64 mask);
-
 #endif /* __KERNEL__ */
 #endif
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 9414d72f664b..8a8949174b1c 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -179,6 +179,23 @@ static void arm_dma_sync_single_for_device(struct device *dev,
 	__dma_page_cpu_to_dev(page, offset, size, dir);
 }
 
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly.  For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask
+ * to this function.
+ */
+static int arm_dma_supported(struct device *dev, u64 mask)
+{
+	unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit);
+
+	/*
+	 * Translate the device's DMA mask to a PFN limit.  This
+	 * PFN number includes the page which we can DMA to.
+	 */
+	return dma_to_pfn(dev, mask) >= max_dma_pfn;
+}
+
 const struct dma_map_ops arm_dma_ops = {
 	.alloc			= arm_dma_alloc,
 	.free			= arm_dma_free,
@@ -219,49 +236,6 @@ const struct dma_map_ops arm_coherent_dma_ops = {
 };
 EXPORT_SYMBOL(arm_coherent_dma_ops);
 
-static int __dma_supported(struct device *dev, u64 mask, bool warn)
-{
-	unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit);
-
-	/*
-	 * Translate the device's DMA mask to a PFN limit.  This
-	 * PFN number includes the page which we can DMA to.
-	 */
-	if (dma_to_pfn(dev, mask) < max_dma_pfn) {
-		if (warn)
-			dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",
-				 mask,
-				 dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,
-				 max_dma_pfn + 1);
-		return 0;
-	}
-
-	return 1;
-}
-
-static u64 get_coherent_dma_mask(struct device *dev)
-{
-	u64 mask = (u64)DMA_BIT_MASK(32);
-
-	if (dev) {
-		mask = dev->coherent_dma_mask;
-
-		/*
-		 * Sanity check the DMA mask - it must be non-zero, and
-		 * must be able to be satisfied by a DMA allocation.
-		 */
-		if (mask == 0) {
-			dev_warn(dev, "coherent DMA mask is unset\n");
-			return 0;
-		}
-
-		if (!__dma_supported(dev, mask, true))
-			return 0;
-	}
-
-	return mask;
-}
-
 static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag)
 {
 	/*
@@ -688,7 +662,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 			 gfp_t gfp, pgprot_t prot, bool is_coherent,
 			 unsigned long attrs, const void *caller)
 {
-	u64 mask = get_coherent_dma_mask(dev);
+	u64 mask = min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
 	struct page *page = NULL;
 	void *addr;
 	bool allowblock, cma;
@@ -712,9 +686,6 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 	}
 #endif
 
-	if (!mask)
-		return NULL;
-
 	buf = kzalloc(sizeof(*buf),
 		      gfp & ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM));
 	if (!buf)
@@ -1087,17 +1058,6 @@ void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 					    dir);
 }
 
-/*
- * Return whether the given device DMA address mask can be supported
- * properly.  For example, if your device can only drive the low 24-bits
- * during bus mastering, then you would pass 0x00ffffff as the mask
- * to this function.
- */
-int arm_dma_supported(struct device *dev, u64 mask)
-{
-	return __dma_supported(dev, mask, false);
-}
-
 static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent)
 {
 	/*