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    SubjectRe: [PATCH 10/21] block: Add fops atomic write support
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    On 10/5/23 21:31, Dave Chinner wrote:
    > Then I don't see what your concern is.
    >
    > Single sector writes are guaranteed atomic and have been for as long
    > as I've worked in this game. OTOH, multi-sector writes are not
    > guaranteed to be atomic - they can get torn on sector boundaries, but
    > the individual sectors within that write are guaranteed to be
    > all-or-nothing.
    >
    > Any hardware device that does not guarantee single sector write
    > atomicity (i.e. tears in the middle of a sector) is, by definition,
    > broken. And we all know that broken hardware means nothing in the
    > storage stack works as it should, so I just don't see what point you
    > are trying to make...

    Do you agree that the above implies that it is not useful in patch 01/21
    of this series to track atomic_write_unit_min_bytes in the block layer
    nor to export this information to user space? The above implies that
    this parameter will always be equal to the logical block size. Writes to
    a single physical block happen atomically. If there are multiple logical
    blocks per physical block, the block device must serialize
    read/modify/write cycles internally.

    Thanks,

    Bart.

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