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authorChristoph Hellwig <hch@lst.de>2017-08-25 17:06:13 +0200
committerChristoph Hellwig <hch@lst.de>2017-08-29 10:04:02 +0200
commit2fd523c57e520899e05ec663d04743005bcef5b2 (patch)
tree6ad337a06d411c03ec463436ef7b694ce2b31a7c /Documentation/DMA-API.txt
parent7f683b920479530150cafbed9dc02eeafb90486b (diff)
downloadlwn-2fd523c57e520899e05ec663d04743005bcef5b2.tar.gz
lwn-2fd523c57e520899e05ec663d04743005bcef5b2.zip
dma-mapping: remove dma_alloc_noncoherent and dma_free_noncoherent
No users left, everyone switched to the _attrs versions. Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'Documentation/DMA-API.txt')
-rw-r--r--Documentation/DMA-API.txt30
1 files changed, 16 insertions, 14 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 45b29326d719..ef3a04fcad65 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -515,14 +515,15 @@ API at all.
::
void *
- dma_alloc_noncoherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag)
+ dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
+ gfp_t flag, unsigned long attrs)
-Identical to dma_alloc_coherent() except that the platform will
-choose to return either consistent or non-consistent memory as it sees
-fit. By using this API, you are guaranteeing to the platform that you
-have all the correct and necessary sync points for this memory in the
-driver should it choose to return non-consistent memory.
+Identical to dma_alloc_coherent() except that when the
+DMA_ATTR_NON_CONSISTENT flags is passed in the attrs argument, the
+platform will choose to return either consistent or non-consistent memory
+as it sees fit. By using this API, you are guaranteeing to the platform
+that you have all the correct and necessary sync points for this memory
+in the driver should it choose to return non-consistent memory.
Note: where the platform can return consistent memory, it will
guarantee that the sync points become nops.
@@ -535,12 +536,13 @@ that simply cannot make consistent memory.
::
void
- dma_free_noncoherent(struct device *dev, size_t size, void *cpu_addr,
- dma_addr_t dma_handle)
+ dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t dma_handle, unsigned long attrs)
-Free memory allocated by the nonconsistent API. All parameters must
-be identical to those passed in (and returned by
-dma_alloc_noncoherent()).
+Free memory allocated by the dma_alloc_attrs(). All parameters common
+parameters must identical to those otherwise passed to dma_fre_coherent,
+and the attrs argument must be identical to the attrs passed to
+dma_alloc_attrs().
::
@@ -564,8 +566,8 @@ memory or doing partial flushes.
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction direction)
-Do a partial sync of memory that was allocated by
-dma_alloc_noncoherent(), starting at virtual address vaddr and
+Do a partial sync of memory that was allocated by dma_alloc_attrs() with
+the DMA_ATTR_NON_CONSISTENT flag starting at virtual address vaddr and
continuing on for size. Again, you *must* observe the cache line
boundaries when doing this.