tree:   https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git feature/dax
head:   091bcf7a76b4e2f32dcfc2d06b147c1f6f2708ac
commit: 9d426c312e68c1d9e450fae0cf07342c230c4166 [6/11] f2fs: support dax address space operation
config: x86_64-randconfig-r013-20210826 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project ea08c4cd1c0869ec5024a8bb3f5cdf06ab03ae83)
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/chao/linux.git/commit/?id=9d426c312e68c1d9e450fae0cf07342c230c4166
        git remote add chao-linux https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git
        git fetch --no-tags chao-linux feature/dax
        git checkout 9d426c312e68c1d9e450fae0cf07342c230c4166
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> fs/f2fs/data.c:4260:9: error: implicit declaration of function 'dax_writeback_mapping_range' [-Werror,-Wimplicit-function-declaration]
           return dax_writeback_mapping_range(mapping, sbi->s_daxdev, wbc);
                  ^
   1 error generated.


vim +/dax_writeback_mapping_range +4260 fs/f2fs/data.c

  4251	
  4252	static int f2fs_dax_writepages(struct address_space *mapping,
  4253						struct writeback_control *wbc)
  4254	{
  4255		struct f2fs_sb_info *sbi = F2FS_I_SB(mapping->host);
  4256	
  4257		if (unlikely(f2fs_cp_error(sbi)))
  4258			return -EIO;
  4259	
> 4260		return dax_writeback_mapping_range(mapping, sbi->s_daxdev, wbc);
  4261	}
  4262	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org