mm/filemap: don't cast ->readpage to filler_t for do_read_cache_page (6c45b454) · Commits · 戴 / test

We can just pass a NULL filler and do the right thing inside of do_read_cache_page based on the NULL parameter. Link: http://lkml.kernel.org/r/20190520055731.24538-3-hch@lst.de Signed-off-by:

Kees Cook <keescook@chromium.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Sami Tolvanen <samitolvanen@google.com> Signed-off-by:

include/linux/pagemap.h

+1 −2

Original line number	Diff line number	Diff line
		@@ -383,8 +383,7 @@ extern int read_cache_pages(struct address_space *mapping,
		static inline struct page read_mapping_page(struct address_space mapping,
		pgoff_t index, void *data)
		{
		filler_t filler = (filler_t )mapping->a_ops->readpage;
		return read_cache_page(mapping, index, filler, data);
		return read_cache_page(mapping, index, NULL, data);
		}

		/*

+6 −4

Original line number	Diff line number	Diff line
		@@ -2825,7 +2825,11 @@ repeat:
		}

		filler:
		if (filler)
		err = filler(data, page);
		else
		err = mapping->a_ops->readpage(data, page);

		if (err < 0) {
		put_page(page);
		return ERR_PTR(err);
		@@ -2937,9 +2941,7 @@ struct page read_cache_page_gfp(struct address_space mapping,
		pgoff_t index,
		gfp_t gfp)
		{
		filler_t filler = (filler_t )mapping->a_ops->readpage;

		return do_read_cache_page(mapping, index, filler, NULL, gfp);
		return do_read_cache_page(mapping, index, NULL, NULL, gfp);
		}
		EXPORT_SYMBOL(read_cache_page_gfp);