Re: [akpm-mm:mm-unstable 179/180] fs/xfs/xfs_file.c:1273:1: warning: no previous prototype for 'xfs_dax_fault'

[Andrew Morton]

On Sat, 4 Jun 2022 20:33:01 +0800 kernel test robot <lkp@xxxxxxxxx> wrote:

> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> head:   f06e3c5104126b9a6660b58f29619b53bfa33b2b
> commit: d5f5b32dee7c09e3152cbbce45c73f0b1ea7d94c [179/180] xfs: support CoW in fsdax mode
> config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20220604/202206042008.WcIK2oVM-lkp@xxxxxxxxx/config)
> compiler: mips-linux-gcc (GCC) 11.3.0
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?id=d5f5b32dee7c09e3152cbbce45c73f0b1ea7d94c
>         git remote add akpm-mm https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git
>         git fetch --no-tags akpm-mm mm-unstable
>         git checkout d5f5b32dee7c09e3152cbbce45c73f0b1ea7d94c
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash fs/xfs/
> 
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> 
> All warnings (new ones prefixed by >>):
> 
> >> fs/xfs/xfs_file.c:1273:1: warning: no previous prototype for 'xfs_dax_fault' [-Wmissing-prototypes]
>     1273 | xfs_dax_fault(
>          | ^~~~~~~~~~~~~
> 

Works OK for me with gcc-12.1.0.

I assume this will fix it.

--- a/fs/xfs/xfs_file.c~xfs-support-cow-in-fsdax-mode-fix
+++ a/fs/xfs/xfs_file.c
@@ -1256,7 +1256,7 @@ xfs_file_llseek(
 }
 
 #ifdef CONFIG_FS_DAX
-int
+static int
 xfs_dax_fault(
 	struct vm_fault		*vmf,
 	enum page_entry_size	pe_size,
@@ -1269,7 +1269,7 @@ xfs_dax_fault(
 				&xfs_read_iomap_ops);
 }
 #else
-int
+static int
 xfs_dax_fault(
 	struct vm_fault		*vmf,
 	enum page_entry_size	pe_size,
_