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authorSumit Semwal <sumit.semwal@linaro.org>2013-03-22 18:22:16 +0530
committerSumit Semwal <sumit.semwal@linaro.org>2013-05-01 16:35:36 +0530
commit78df969550e7187f4dcd70b737217dcbc8e9a06a (patch)
treea10524a478ce83555904ce27363bd68140f031bc /Documentation/dma-buf-sharing.txt
parent5f56886521d6ddd3648777fae44d82382dd8c87f (diff)
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dma-buf: replace dma_buf_export() with dma_buf_export_named()
For debugging purposes, it is useful to have a name-string added while exporting buffers. Hence, dma_buf_export() is replaced with dma_buf_export_named(), which additionally takes 'exp_name' as a parameter. For backward compatibility, and for lazy exporters who don't wish to name themselves, a #define dma_buf_export() is also made available, which adds a __FILE__ instead of 'exp_name'. Cc: Daniel Vetter <daniel.vetter@ffwll.ch> [Thanks for the idea!] Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Diffstat (limited to 'Documentation/dma-buf-sharing.txt')
-rw-r--r--Documentation/dma-buf-sharing.txt13
1 files changed, 11 insertions, 2 deletions
diff --git a/Documentation/dma-buf-sharing.txt b/Documentation/dma-buf-sharing.txt
index 4966b1b..0b23261 100644
--- a/Documentation/dma-buf-sharing.txt
+++ b/Documentation/dma-buf-sharing.txt
@@ -52,14 +52,23 @@ The dma_buf buffer sharing API usage contains the following steps:
associated with this buffer.
Interface:
- struct dma_buf *dma_buf_export(void *priv, struct dma_buf_ops *ops,
- size_t size, int flags)
+ struct dma_buf *dma_buf_export_named(void *priv, struct dma_buf_ops *ops,
+ size_t size, int flags,
+ const char *exp_name)
If this succeeds, dma_buf_export allocates a dma_buf structure, and returns a
pointer to the same. It also associates an anonymous file with this buffer,
so it can be exported. On failure to allocate the dma_buf object, it returns
NULL.
+ 'exp_name' is the name of exporter - to facilitate information while
+ debugging.
+
+ Exporting modules which do not wish to provide any specific name may use the
+ helper define 'dma_buf_export()', with the same arguments as above, but
+ without the last argument; a __FILE__ pre-processor directive will be
+ inserted in place of 'exp_name' instead.
+
2. Userspace gets a handle to pass around to potential buffer-users
Userspace entity requests for a file-descriptor (fd) which is a handle to the
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