Re: [PATCH v8 1/3] lib: zstd: Add kernel-specific API

[Nick Terrell]

On Sat, Mar 27, 2021 at 2:48 PM Oleksandr Natalenko
<oleksandr@xxxxxxxxxxxxxx> wrote:
>
> Hello.
>
> On Sat, Mar 27, 2021 at 05:48:01PM +0800, kernel test robot wrote:
> > >> ERROR: modpost: "ZSTD_maxCLevel" [fs/f2fs/f2fs.ko] undefined!
>
> Since f2fs can be built as a module, the following correction seems to
> be needed:

Thanks Oleksandr! Looks like f2fs has been updated to use
ZSTD_maxCLevel() since the first version of these patches. I'll put up
a new version shortly with the fix, and update my test suite to build
f2fs and other users as modules, so it can catch this.

Best,
Nick

> ```
> diff --git a/lib/zstd/compress/zstd_compress.c b/lib/zstd/compress/zstd_compress.c
> index 9c998052a0e5..584c92c51169 100644
> --- a/lib/zstd/compress/zstd_compress.c
> +++ b/lib/zstd/compress/zstd_compress.c
> @@ -4860,6 +4860,7 @@ size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
>
>  #define ZSTD_MAX_CLEVEL     22
>  int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
> +EXPORT_SYMBOL(ZSTD_maxCLevel);
>  int ZSTD_minCLevel(void) { return (int)-ZSTD_TARGETLENGTH_MAX; }
>
>  static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL+1] = {
> ```
>
> Not sure if the same should be done for `ZSTD_minCLevel()` since I don't
> see it being used anywhere else.
>
> --
>   Oleksandr Natalenko (post-factum)