[05/16] mm: add prototype for __add_to_page_cache_locked()

Commit Message

Andrew Morton Dec. 29, 2020, 11:14 p.m. UTC

From: Souptick Joarder <[e-mail]>
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/[e-mail]
Signed-off-by: Souptick Joarder <[e-mail]>
Cc: Alex Shi <[e-mail]>
Cc: Matthew Wilcox <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/mm.h |    7 +++++++
 1 file changed, 7 insertions(+)

Patch

--- 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))