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    SubjectRe: [PATCH] 2.6.10 - direct-io async short read bug
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    On Tue, 2005-03-08 at 17:44, Daniel McNeil wrote:
    > On Tue, 2005-03-08 at 11:18, Badari Pulavarty wrote:
    > > > Andrew, please don't apply the original patch. We shouldn't even attempt
    > > > to submit IO beyond the filesize. We should truncate the IO request to
    > > > filesize. I will send a patch today to fix this.
    > > >
    > >
    > > Well, spoke too soon. This is an ugly corner case :( But I have
    > > a ugly hack to fix it :)
    > >
    > > Let me ask you a basic question: Do we support DIO reads on a file
    > > which is not blocksize multiple in size ? (say 12K - 10 bytes) ?
    > >
    > > What about the ones which are not 4K but 512 byte multiple ? (say 7K) ?
    > >
    > > I need answer to those, to figure out how hard I should try to fix this.
    > >
    > > Anyway, here is ugly version of the patch - which will limit the IO
    > > size to filesize and uses lower blocksizes to read the file (since
    > > the filesize is only 3K, it would go down to 512 byte blocksize).
    > >
    >
    > BTW, I got a compile error because the 'iov' parameter is
    > declared with 'const', so your patch is changing a read-only
    > value. :(
    >
    > Daniel
    >

    Told you, it was ugly and I noted in the comments too :)

    BTW, I don't think that is the correct solution. I guess,
    we need to do the IO beyond EOF and zero out the data.
    And also, this can happen only if the EOF is in the middle
    of the block - so its an issue only for the last block.

    What do you think ?

    Thanks,
    Badari
    >

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