Hi Gao,

I love your patch! Perhaps something to improve:

[auto build test WARNING on xiang-erofs/dev-test]
[cannot apply to xfs-linux/for-next linux/master linus/master v5.14-rc1 next-20210716]
[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/Gao-Xiang/erofs-iomap-support-for-tailpacking-cases/20210716-130821
base:   https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git dev-test
config: x86_64-randconfig-s032-20210716 (attached as .config)
compiler: gcc-10 (Ubuntu 10.3.0-1ubuntu1~20.04) 10.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.3-341-g8af24329-dirty
        # https://github.com/0day-ci/linux/commit/9bd9c1ccdf3e99ffd9a76cfec92691e460abd74d
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Gao-Xiang/erofs-iomap-support-for-tailpacking-cases/20210716-130821
        git checkout 9bd9c1ccdf3e99ffd9a76cfec92691e460abd74d
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 

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 >>):

>> fs/erofs/data.c:133:5: warning: no previous prototype for 'erofs_iomap_end' [-Wmissing-prototypes]
     133 | int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length,
         |     ^~~~~~~~~~~~~~~


sparse warnings: (new ones prefixed by >>)
>> fs/erofs/data.c:133:5: sparse: sparse: symbol 'erofs_iomap_end' was not declared. Should it be static?
   fs/erofs/data.c:148:24: sparse: sparse: symbol 'erofs_iomap_ops' was not declared. Should it be static?

Please review and possibly fold the followup patch.

vim +/erofs_iomap_end +133 fs/erofs/data.c

   132	
 > 133	int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length,
   134			ssize_t written, unsigned flags, struct iomap *iomap)
   135	{
   136		struct page *ipage = iomap->private;
   137	
   138		if (ipage) {
   139			DBG_BUGON(iomap->type != IOMAP_INLINE);
   140			unlock_page(ipage);
   141			put_page(ipage);
   142		} else {
   143			DBG_BUGON(iomap->type == IOMAP_INLINE);
   144		}
   145		return written;
   146	}
   147	

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