Otherwise subsystems will get this wrong and end up with a second export ioctl with the flag and O_CLOEXEC support added.
v2: Fixup the function name and caution exporters to limit the flags to only O_CLOEXEC. Noted by Dave Airlie.
Cc: Dave Airlie airlied@gmail.com Signed-Off-by: Daniel Vetter daniel.vetter@ffwll.ch --- Documentation/dma-buf-sharing.txt | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/Documentation/dma-buf-sharing.txt b/Documentation/dma-buf-sharing.txt index 9f3aeef..a6d4c37 100644 --- a/Documentation/dma-buf-sharing.txt +++ b/Documentation/dma-buf-sharing.txt @@ -319,6 +319,12 @@ Miscellaneous notes - Any exporters or users of the dma-buf buffer sharing framework must have a 'select DMA_SHARED_BUFFER' in their respective Kconfigs.
+- To avoid the wrath of userspace library writers exporting subsystems must have + a flag parameter in the ioctl that creates the dma-buf fd which needs to + support at least the O_CLOEXEC fd flag. This needs to be passed in the flag + parameter of dma_buf_fd. Without any other reasons applying it is recommended + that exporters limit the flags passed to dma_buf_fd to only O_CLOEXEC. + References: [1] struct dma_buf_ops in include/linux/dma-buf.h [2] All interfaces mentioned above defined in include/linux/dma-buf.h