Re: [PATCH v2 3/4] erofs: Don't use certain internal folio_*() functions

[Gao Xiang]

Hi Matthew,

On 2024/1/15 22:06, Matthew Wilcox wrote:
> On Mon, Jan 15, 2024 at 04:33:37PM +0800, Gao Xiang wrote:
> > From: David Howells <dhowells@xxxxxxxxxx>
> >
> > Filesystems should use folio->index and folio->mapping, instead of
> > folio_index(folio), folio_mapping() and folio_file_mapping() since
> > they know that it's in the pagecache.
> >
> > Change this automagically with:
> >
> > perl -p -i -e 's/folio_mapping[(]([^)]*)[)]/\1->mapping/g' fs/erofs/*.c
> > perl -p -i -e 's/folio_file_mapping[(]([^)]*)[)]/\1->mapping/g' fs/erofs/*.c
> > perl -p -i -e 's/folio_index[(]([^)]*)[)]/\1->index/g' fs/erofs/*.c
> >
> > Reported-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> > Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
> > Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > Cc: Chao Yu <chao@xxxxxxxxxx>
> > Cc: Yue Hu <huyue2@xxxxxxxxxxx>
> > Cc: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx>
> > Cc: linux-erofs@xxxxxxxxxxxxxxxx
> > Cc: linux-fsdevel@xxxxxxxxxxxxxxx
> > Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
> > ---
> > Hi folks,
> >
> > I tend to apply this patch upstream since compressed data fscache
> > adaption touches this part too.  If there is no objection, I'm
> > going to take this patch separately for -next shortly..
>
> Could you change the subject?  It's not that the functions are
> "internal", it's that filesystems don't need to use them because they're
> guaranteed to not see swap pages.  Maybe just s/internal/unnecessary/

Yes, the subject line was inherited from the original one.

Such helpers are useful if the type of a folio is unknown,
let me revise it.

Thanks,
Gao Xiang