Commits
Yan, Zheng committed c8fe9b17d05
ceph: Asynchronous IO support The basic idea of AIO support is simple, just call kiocb::ki_complete() in OSD request's complete callback. But there are several special cases. when IO span multiple objects, we need to wait until all OSD requests are complete, then call kiocb::ki_complete(). Error handling in this case is tricky too. For simplify, AIO both span multiple objects and extends i_size are not allowed. Another special case is check EOF for reading (other client can write to the file and extend i_size concurrently). For simplify, the direct-IO/AIO code path does do the check, fallback to normal syn read instead. Signed-off-by: Yan, Zheng <zyan@redhat.com>