Re: [PATCH v9 92/96] iomap: Convert iomap_write_begin and iomap_write_end to folios

[Matthew Wilcox <willy@xxxxxxxxxxxxx>]

On Thu, May 06, 2021 at 05:36:54AM +0800, kernel test robot wrote:
> config: nds32-defconfig (attached as .config)
>    fs/iomap/buffered-io.c: In function '__iomap_write_end':
> >> fs/iomap/buffered-io.c:645:2: error: implicit declaration of function 'flush_dcache_folio'; did you mean 'flush_dcache_page'? [-Werror=implicit-function-declaration]
>      645 |  flush_dcache_folio(folio);
>          |  ^~~~~~~~~~~~~~~~~~
>          |  flush_dcache_page
>    cc1: some warnings being treated as errors

Argh, nds32 doesn't (always) include asm-generic/cacheflush.h, so it
doesn't pick up the generic implementation of flush_dcache_folio().
Copy-and-pasted it to nds32.

Thanks.