Christoph Hellwig <hch@xxxxxx> wrote: > The whole idea of an out of band interface is going to be racy and suffer > from implementation loss. I think what you want is something similar to > the NFSv4.2 READ_PLUS operation - give me that if there is any and > otherwise tell me that there is a hole. I think this could be a new > RWF_NOHOLE or similar flag, just how to return the hole size would be > a little awkward. Maybe return a specific negative error code (ENODATA?) > and advance the iov anyway. Just having call_iter_read() return a short read could be made to suffice... provided the filesystem doesn't return data I haven't written in (which could cause apparent corruption) and does return data I have written in (otherwise I have to go back to the server). David
