From: Souptick Joarder <jrdr.linux@xxxxxxxxx> Subject: mm: add prototype for __add_to_page_cache_locked() Otherwise it causes a gcc warning: ../mm/filemap.c:830:14: warning: no previous prototype for `__add_to_page_cache_locked' [-Wmissing-prototypes] A previous attempt to make this function static led to compilation errors when CONFIG_DEBUG_INFO_BTF is enabled because __add_to_page_cache_locked() is referred to by BPF code. Adding a prototype will silence the warning. Link: https://lkml.kernel.org/r/1608693702-4665-1-git-send-email-jrdr.linux@xxxxxxxxx Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx> Cc: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm.h | 7 +++++++ 1 file changed, 7 insertions(+) --- a/include/linux/mm.h~mm-add-prototype-for-__add_to_page_cache_locked +++ a/include/linux/mm.h @@ -216,6 +216,13 @@ int overcommit_kbytes_handler(struct ctl loff_t *); int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *, loff_t *); +/* + * Any attempt to mark this function as static leads to build failure + * when CONFIG_DEBUG_INFO_BTF is enabled because __add_to_page_cache_locked() + * is referred to by BPF code. This must be visible for error injection. + */ +int __add_to_page_cache_locked(struct page *page, struct address_space *mapping, + pgoff_t index, gfp_t gfp, void **shadowp); #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) _
