Hi Shiyang,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linux/master]
[also build test WARNING on linus/master v5.15-rc7 next-20211029]
[cannot apply to hnaz-mm/master xfs-linux/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Shiyang-Ruan/fsdax-introduce-fs-query-to-support-reflink/20211031-232355
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 2f111a6fd5b5297b4e92f53798ca086f7c7d33a4
config: hexagon-randconfig-r016-20211031 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 82ed106567063ea269c6d5669278b733e173a42f)
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://github.com/0day-ci/linux/commit/c300bbf1e08492a9c8d51182d055c8477082c1e9
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Shiyang-Ruan/fsdax-introduce-fs-query-to-support-reflink/20211031-232355
        git checkout c300bbf1e08492a9c8d51182d055c8477082c1e9
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=hexagon 

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

All warnings (new ones prefixed by >>):

>> drivers/dax/super.c:61:6: warning: no previous prototype for function 'dax_write_lock' [-Wmissing-prototypes]
   void dax_write_lock(struct dax_device *dax_dev)
        ^
   drivers/dax/super.c:61:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void dax_write_lock(struct dax_device *dax_dev)
   ^
   static 
>> drivers/dax/super.c:66:6: warning: no previous prototype for function 'dax_write_unlock' [-Wmissing-prototypes]
   void dax_write_unlock(struct dax_device *dax_dev)
        ^
   drivers/dax/super.c:66:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void dax_write_unlock(struct dax_device *dax_dev)
   ^
   static 
   drivers/dax/super.c:449:6: warning: no previous prototype for function 'run_dax' [-Wmissing-prototypes]
   void run_dax(struct dax_device *dax_dev)
        ^
   drivers/dax/super.c:449:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void run_dax(struct dax_device *dax_dev)
   ^
   static 
   3 warnings generated.


vim +/dax_write_lock +61 drivers/dax/super.c

    60	
  > 61	void dax_write_lock(struct dax_device *dax_dev)
    62	{
    63		percpu_down_write(&dax_dev->rwsem);
    64	}
    65	
  > 66	void dax_write_unlock(struct dax_device *dax_dev)
    67	{
    68		percpu_up_write(&dax_dev->rwsem);
    69	}
    70	

---
0-DAY CI Kernel Test Service, Intel Corporation
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