From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> Document the new function added to sync_file.c v2: Adapt to fence_array Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> --- Documentation/sync_file.txt | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/sync_file.txt b/Documentation/sync_file.txt index eaf8297..46f5769 100644 --- a/Documentation/sync_file.txt +++ b/Documentation/sync_file.txt @@ -64,6 +64,25 @@ The sync_file fd now can be sent to userspace. If the creation process fail, or the sync_file needs to be released by any other reason fput(sync_file->file) should be used. +Receiving Sync Files from Userspace +----------------------------------- + +When userspace needs to send an in-fence to the driver it pass file descriptor +of the Sync File to the kernel. The kernel then can retrieve the sync_file +from it. + +Interface: + struct fence *sync_file_get_fence(int fd); + + +The function return a struct fence pointer referencing the fence(s) in the Sync +File. If the Sync File contains only one fence, this fence is returned. But if +has more than one fence a fence_array[3] is returned. However the callers only +see the arrays' base class which is struct fence. In both cases a reference to +the returned fence is held. + + References: [1] struct sync_file in include/linux/sync_file.h [2] All interfaces mentioned above defined in include/linux/sync_file.h +[1] struct fence_array in include/linux/fence-array.h -- 2.5.5 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
