Merge tag 'dma-mapping-5.15' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - fix debugfs initialization order (Anthony Iliopoulos)

 - use memory_intersects() directly (Kefeng Wang)

 - allow to return specific errors from ->map_sg (Logan Gunthorpe,
   Martin Oliveira)

 - turn the dma_map_sg return value into an unsigned int (me)

 - provide a common global coherent pool іmplementation (me)

* tag 'dma-mapping-5.15' of git://git.infradead.org/users/hch/dma-mapping: (31 commits)
  hexagon: use the generic global coherent pool
  dma-mapping: make the global coherent pool conditional
  dma-mapping: add a dma_init_global_coherent helper
  dma-mapping: simplify dma_init_coherent_memory
  dma-mapping: allow using the global coherent pool for !ARM
  ARM/nommu: use the generic dma-direct code for non-coherent devices
  dma-direct: add support for dma_coherent_default_memory
  dma-mapping: return an unsigned int from dma_map_sg{,_attrs}
  dma-mapping: disallow .map_sg operations from returning zero on error
  dma-mapping: return error code from dma_dummy_map_sg()
  x86/amd_gart: don't set failed sg dma_address to DMA_MAPPING_ERROR
  x86/amd_gart: return error code from gart_map_sg()
  xen: swiotlb: return error code from xen_swiotlb_map_sg()
  parisc: return error code from .map_sg() ops
  sparc/iommu: don't set failed sg dma_address to DMA_MAPPING_ERROR
  sparc/iommu: return error codes from .map_sg() ops
  s390/pci: don't set failed sg dma_address to DMA_MAPPING_ERROR
  s390/pci: return error code from s390_dma_map_sg()
  powerpc/iommu: don't set failed sg dma_address to DMA_MAPPING_ERROR
  powerpc/iommu: return error code from .map_sg() ops
  ...

3 files changed, 36 insertions, 53 deletions

diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 0d53a96a3d64..0d5b06b3a4a6 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -41,8 +41,9 @@ struct dma_map_ops {
 			size_t size, enum dma_data_direction dir,
 			unsigned long attrs);
 	/*
-	 * map_sg returns 0 on error and a value > 0 on success.
-	 * It should never return a value < 0.
+	 * map_sg should return a negative error code on error. See
+	 * dma_map_sgtable() for a list of appropriate error codes
+	 * and their meanings.
 	 */
 	int (*map_sg)(struct device *dev, struct scatterlist *sg, int nents,
 			enum dma_data_direction dir, unsigned long attrs);
@@ -170,13 +171,6 @@ int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
 int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr);
 int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
 		void *cpu_addr, size_t size, int *ret);
-
-void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
-		dma_addr_t *dma_handle);
-int dma_release_from_global_coherent(int order, void *vaddr);
-int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr,
-		size_t size, int *ret);
-
 #else
 static inline int dma_declare_coherent_memory(struct device *dev,
 		phys_addr_t phys_addr, dma_addr_t device_addr, size_t size)
@@ -186,7 +180,16 @@ static inline int dma_declare_coherent_memory(struct device *dev,
 #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0)
 #define dma_release_from_dev_coherent(dev, order, vaddr) (0)
 #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0)
+#endif /* CONFIG_DMA_DECLARE_COHERENT */
 
+#ifdef CONFIG_DMA_GLOBAL_POOL
+void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
+		dma_addr_t *dma_handle);
+int dma_release_from_global_coherent(int order, void *vaddr);
+int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr,
+		size_t size, int *ret);
+int dma_init_global_coherent(phys_addr_t phys_addr, size_t size);
+#else
 static inline void *dma_alloc_from_global_coherent(struct device *dev,
 		ssize_t size, dma_addr_t *dma_handle)
 {
@@ -201,7 +204,7 @@ static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma,
 {
 	return 0;
 }
-#endif /* CONFIG_DMA_DECLARE_COHERENT */
+#endif /* CONFIG_DMA_GLOBAL_POOL */
 
 /*
  * This is the actual return value from the ->alloc_noncontiguous method.
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 183e7103a66d..dca2b1355bb1 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -105,11 +105,13 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
 		unsigned long attrs);
 void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
 		enum dma_data_direction dir, unsigned long attrs);
-int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
-		enum dma_data_direction dir, unsigned long attrs);
+unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
+		int nents, enum dma_data_direction dir, unsigned long attrs);
 void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
 				      int nents, enum dma_data_direction dir,
 				      unsigned long attrs);
+int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
+		enum dma_data_direction dir, unsigned long attrs);
 dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
 		size_t size, enum dma_data_direction dir, unsigned long attrs);
 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
@@ -164,8 +166,9 @@ static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
 		size_t size, enum dma_data_direction dir, unsigned long attrs)
 {
 }
-static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
-		int nents, enum dma_data_direction dir, unsigned long attrs)
+static inline unsigned int dma_map_sg_attrs(struct device *dev,
+		struct scatterlist *sg, int nents, enum dma_data_direction dir,
+		unsigned long attrs)
 {
 	return 0;
 }
@@ -174,6 +177,11 @@ static inline void dma_unmap_sg_attrs(struct device *dev,
 		unsigned long attrs)
 {
 }
+static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
+		enum dma_data_direction dir, unsigned long attrs)
+{
+	return -EOPNOTSUPP;
+}
 static inline dma_addr_t dma_map_resource(struct device *dev,
 		phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
 		unsigned long attrs)
@@ -344,34 +352,6 @@ static inline void dma_sync_single_range_for_device(struct device *dev,
 }
 
 /**
- * dma_map_sgtable - Map the given buffer for DMA
- * @dev:	The device for which to perform the DMA operation
- * @sgt:	The sg_table object describing the buffer
- * @dir:	DMA direction
- * @attrs:	Optional DMA attributes for the map operation
- *
- * Maps a buffer described by a scatterlist stored in the given sg_table
- * object for the @dir DMA operation by the @dev device. After success the
- * ownership for the buffer is transferred to the DMA domain.  One has to
- * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
- * ownership of the buffer back to the CPU domain before touching the
- * buffer by the CPU.
- *
- * Returns 0 on success or -EINVAL on error during mapping the buffer.
- */
-static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
-		enum dma_data_direction dir, unsigned long attrs)
-{
-	int nents;
-
-	nents = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
-	if (nents <= 0)
-		return -EINVAL;
-	sgt->nents = nents;
-	return 0;
-}
-
-/**
  * dma_unmap_sgtable - Unmap the given buffer for DMA
  * @dev:	The device for which to perform the DMA operation
  * @sgt:	The sg_table object describing the buffer
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 32d448050bf7..9369458ba1bd 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -414,11 +414,11 @@ extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
 extern size_t iommu_unmap_fast(struct iommu_domain *domain,
 			       unsigned long iova, size_t size,
 			       struct iommu_iotlb_gather *iotlb_gather);
-extern size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
-			   struct scatterlist *sg,unsigned int nents, int prot);
-extern size_t iommu_map_sg_atomic(struct iommu_domain *domain,
-				  unsigned long iova, struct scatterlist *sg,
-				  unsigned int nents, int prot);
+extern ssize_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
+		struct scatterlist *sg, unsigned int nents, int prot);
+extern ssize_t iommu_map_sg_atomic(struct iommu_domain *domain,
+				   unsigned long iova, struct scatterlist *sg,
+				   unsigned int nents, int prot);
 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova);
 extern void iommu_set_fault_handler(struct iommu_domain *domain,
 			iommu_fault_handler_t handler, void *token);
@@ -679,18 +679,18 @@ static inline size_t iommu_unmap_fast(struct iommu_domain *domain,
 	return 0;
 }
 
-static inline size_t iommu_map_sg(struct iommu_domain *domain,
-				  unsigned long iova, struct scatterlist *sg,
-				  unsigned int nents, int prot)
+static inline ssize_t iommu_map_sg(struct iommu_domain *domain,
+				   unsigned long iova, struct scatterlist *sg,
+				   unsigned int nents, int prot)
 {
-	return 0;
+	return -ENODEV;
 }
 
-static inline size_t iommu_map_sg_atomic(struct iommu_domain *domain,
+static inline ssize_t iommu_map_sg_atomic(struct iommu_domain *domain,
 				  unsigned long iova, struct scatterlist *sg,
 				  unsigned int nents, int prot)
 {
-	return 0;
+	return -ENODEV;
 }
 
 static inline void iommu_flush_iotlb_all(struct iommu_domain *domain)