From 6c45b454191b330c8bc21d1ed3cf39bb6da1a4eb Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 11 Jul 2019 20:55:20 -0700 Subject: [PATCH] mm/filemap: don't cast ->readpage to filler_t for do_read_cache_page 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: Christoph Hellwig Reviewed-by: Kees Cook Cc: Nick Desaulniers Cc: Sami Tolvanen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 3 +-- mm/filemap.c | 10 ++++++---- 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 6fd0d3aa492c..c7552459a15f 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -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); } /* diff --git a/mm/filemap.c b/mm/filemap.c index d6f7596f148f..1e5e006b8557 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2825,7 +2825,11 @@ repeat: } filler: - err = filler(data, page); + 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);