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. Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx> Cc: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> --- v2: Updated change logs and code comments as per review. s/offset/index. include/linux/mm.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5299b90a..c1e9081 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -216,6 +216,13 @@ int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *, 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)) -- 1.9.1
