[goldwynr:iomap 29/33] fs/btrfs/inode.c:8440:24: sparse: sparse: symbol 'btrfs_buffered_read_iomap_ops' was not declared. Should it be static?

[kernel test robot]

tree:   https://github.com/goldwynr/linux iomap
head:   30c74a8c201365178cae26d0d7aefa120c3245ab
commit: 3f7d55b62cade444975e4452af7b623c78bc48ef [29/33] btrfs: iomap_begin() for buffered read
config: i386-randconfig-s001-20211228 (https://download.01.org/0day-ci/archive/20211230/202112301510.SuWKl9nZ-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-dirty
        # https://github.com/goldwynr/linux/commit/3f7d55b62cade444975e4452af7b623c78bc48ef
        git remote add goldwynr https://github.com/goldwynr/linux
        git fetch --no-tags goldwynr iomap
        git checkout 3f7d55b62cade444975e4452af7b623c78bc48ef
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash fs/btrfs/

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


sparse warnings: (new ones prefixed by >>)
>> fs/btrfs/inode.c:8440:24: sparse: sparse: symbol 'btrfs_buffered_read_iomap_ops' was not declared. Should it be static?

Please review and possibly fold the followup patch.

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