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authorYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>2019-08-28 15:35:40 +0300
committerChristoph Hellwig <hch@lst.de>2019-09-03 09:33:01 +0300
commit6ba99411b858bd70bae966633561e698cd6de38c (patch)
tree5679bf75e3c4fc1a8bba626da01c2d0ce42f556f /include/linux/dma-mapping.h
parent38c38cb73223218f6eedf485280917af1f8a0af2 (diff)
downloadlinux-6ba99411b858bd70bae966633561e698cd6de38c.tar.xz
dma-mapping: introduce dma_get_merge_boundary()
This patch adds a new DMA API "dma_get_merge_boundary". This function returns the DMA merge boundary if the DMA layer can merge the segments. This patch also adds the implementation for a new dma_map_ops pointer. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'include/linux/dma-mapping.h')
-rw-r--r--include/linux/dma-mapping.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 48ebe8295987..de41a4f0b9f6 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -131,6 +131,7 @@ struct dma_map_ops {
int (*dma_supported)(struct device *dev, u64 mask);
u64 (*get_required_mask)(struct device *dev);
size_t (*max_mapping_size)(struct device *dev);
+ unsigned long (*get_merge_boundary)(struct device *dev);
};
#define DMA_MAPPING_ERROR (~(dma_addr_t)0)
@@ -467,6 +468,7 @@ int dma_set_mask(struct device *dev, u64 mask);
int dma_set_coherent_mask(struct device *dev, u64 mask);
u64 dma_get_required_mask(struct device *dev);
size_t dma_max_mapping_size(struct device *dev);
+unsigned long dma_get_merge_boundary(struct device *dev);
#else /* CONFIG_HAS_DMA */
static inline dma_addr_t dma_map_page_attrs(struct device *dev,
struct page *page, size_t offset, size_t size,
@@ -572,6 +574,10 @@ static inline size_t dma_max_mapping_size(struct device *dev)
{
return 0;
}
+static inline unsigned long dma_get_merge_boundary(struct device *dev)
+{
+ return 0;
+}
#endif /* CONFIG_HAS_DMA */
static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,