O_DIRECT in ext4 with data=journaled mount option enabled

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http://stackoverflow.com – As far as I know in ext4 the O_DIRECT flag support with journalling on was added only in some recent kernel versions. I know it wasn't there with 3.0.0 kernel but it already works fine with 3.4, so I'm trying to find out which is the lowest possible version, not to disable the feature everywhere but to do it after a kernel version check. I looked up some ext4 documentations, found some patches but still don't know the exact version. Is there any help you can suggest? (HowTos)