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    SubjectRe: Question of resource_size() implementation
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    On Tue, 2009-12-29 at 16:12 -0800, Joe Perches wrote:
    > On Wed, 2009-12-30 at 01:43 +0200, Felipe Balbi wrote:
    > > I'm wondering whether the +1 in resource_size() is actually necessary.
    > > resource_size() is defined as:
    > []
    > > static inline resource_size_t resource_size(const struct resource *res)
    > > {
    > > return res->end - res->start + 1;
    > > }
    > > Are we off-by-one
    > > here ? Or is this all expected ?
    >
    > Imagine you have 1 byte sized resources.
    >
    > AREA1 = 0x40000000
    > AREA2 = 0x40000001
    >
    > area1.start = 0x40000000
    > area1.end = 0x40000000
    >
    > area2.start = 0x40000001
    > area2.end = 0x40000001

    (adding lkml back to the loop)

    in that you wouldn't use any of the SZ_* macros and simply hardcode
    start and end, right ? then you would define:

    area1.start = 0x40000000
    area1.end = 0x40000001

    and ioremap 2 bytes due to +1 in resource_size().

    --
    balbi



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