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    SubjectRe: Size of sector_t in userspace [Was: fix 41 'make headers_check' warnings]
    On Wed, Jan 21 2009, Sam Ravnborg wrote:
    > Hi Jens.
    >
    > In an attempt to fix some of the issues in our exported Headers jsr
    > encountered some strange stuff in types.h.
    >
    > types.h is exported to userspace where we do not have access to CONFIG_*
    > symbols.
    > Despite this we use CONFGI_LBD to decide the size of sector_t like this:
    >
    > #ifdef CONFIG_LBD
    > typedef u64 sector_t;
    > typedef u64 blkcnt_t;
    > #else
    > typedef unsigned long sector_t;
    > typedef unsigned long blkcnt_t;
    > #endif
    >
    > But as CONFIG_LBD is never defined in userspace sector_t is now 32
    > bit on 32 bit boxes and 64 bit on 64 bit boxes (in userspace).
    >
    > Is sector:t (and the companion blkcnt_t) really used by userspace?
    > If it is - what size is it expected to have?

    I don't think it's used by userspace, at least it cannot be used in
    userspace <-> kernelspace interactions, since the size isn't fixed.

    --
    Jens Axboe



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