path: root/Documentation/DMA-API.txt
diff options
authorJoerg Roedel <jroedel@suse.de>2019-02-07 11:59:15 (GMT)
committerMichael S. Tsirkin <mst@redhat.com>2019-03-06 16:19:11 (GMT)
commit133d624b1cee16906134e92d5befb843b58bcf31 (patch)
treeb5d5d7d1ce51dca0a90402227028eee5ded9ba6b /Documentation/DMA-API.txt
parent492366f7b4237257ef50ca9c431a6a0d50225aca (diff)
dma: Introduce dma_max_mapping_size()
The function returns the maximum size that can be mapped using DMA-API functions. The patch also adds the implementation for direct DMA and a new dma_map_ops pointer so that other implementations can expose their limit. Cc: stable@vger.kernel.org Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'Documentation/DMA-API.txt')
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index e133ccd..acfe3d0 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -195,6 +195,14 @@ Requesting the required mask does not alter the current mask. If you
wish to take advantage of it, you should issue a dma_set_mask()
call to set the mask to the value returned.
+ size_t
+ dma_direct_max_mapping_size(struct device *dev);
+Returns the maximum size of a mapping for the device. The size parameter
+of the mapping functions like dma_map_single(), dma_map_page() and
+others should not be larger than the returned value.
Part Id - Streaming DMA mappings