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    SubjectRe: [PATCH] aio: propogate post-EIOCBQUEUED errors to completion event
    Date
    >> There are some strange O_DIRECT corner cases in here such that the  
    >> 'last
    >> writer' may actually be a 'last reader' and winning can mean have
    >> a copy
    >> of the page in page cache older than the copy on disk.
    >
    > As long as it is marked dirty so that it eventually gets synced to
    > disk,
    > it shouldn't matter.

    No, Chris is pointing out that an an O_DIRECT write can leave clean
    read pages in the page cache.

    All it takes is giving a source buffer for the write which is an mmap
    ()ed apeture of the region that is being written to. If you get the
    offsets right you can get the get_user_pages() down in fs/direct-io.c
    will populate the page cache before the actual O_DIRECT write gets to
    it.

    - z
    -
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