Re: Radix tree range entries

[Dan Williams]

On Tue, Jan 31, 2017 at 8:59 AM, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> Hi Dan, Konstantin,
>
> You've been interested in using range entries in the radix tree rather
> than higher-order entries.  I've built a range entry interface on top
> of our current radix tree substrate, and it seems to be behaving itself
> in the test suite.  Would you care to try out this patch?  Ideas for
> other tests to add to the test suite would be appreciated too.
>
> There may be some minor conflicts with the current Linus tree; the full
> patch series can be found here:
>
> http://git.infradead.org/users/willy/linux-dax.git/shortlog/refs/heads/idr-20170131
>
> commit b6444c0557bc1ac5add3c8db66d26a7ba7ccd6a6
> Author: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
> Date:   Tue Jan 31 11:16:47 2017 -0500
>
>     radix-tree: Add range entry support
>
>     We have a confirmed customer in the shape of devm_memremap_pages(), so
>     add support for range entries.  The documentation lists caveats on their
>     use, but none of these caveats apply to the one user.
>
>     Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>

Thanks, I'll take a look. This will let me get rid of the order_at()
hack I have in devm_memremap_pages(). I assume there's no requirement
that 'start' be aligned to 'len' when calling
radix_tree_insert_range()?