Hi Chao,

I love your patch! Yet something to improve:

[auto build test ERROR on f2fs/dev-test]
[also build test ERROR on v5.6-rc4 next-20200303]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Chao-Yu/f2fs-compress-support-zstd-compress-algorithm/20200304-020312
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git dev-test
config: x86_64-randconfig-s1-20200303 (attached as .config)
compiler: gcc-7 (Debian 7.5.0-5) 7.5.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

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

All errors (new ones prefixed by >>):

   fs/f2fs/compress.c:450:3: error: 'const struct f2fs_compress_ops' has no member named 'init_decompress_ctx'; did you mean 'init_compress_ctx'?
     .init_decompress_ctx = zstd_init_decompress_ctx,
      ^~~~~~~~~~~~~~~~~~~
      init_compress_ctx
>> fs/f2fs/compress.c:450:25: error: positional initialization of field in 'struct' declared with 'designated_init' attribute [-Werror=designated-init]
     .init_decompress_ctx = zstd_init_decompress_ctx,
                            ^~~~~~~~~~~~~~~~~~~~~~~~
   fs/f2fs/compress.c:450:25: note: (near initialization for 'f2fs_zstd_ops')
   fs/f2fs/compress.c:450:25: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
   fs/f2fs/compress.c:450:25: note: (near initialization for 'f2fs_zstd_ops.destroy_compress_ctx')
   fs/f2fs/compress.c:451:3: error: 'const struct f2fs_compress_ops' has no member named 'destroy_decompress_ctx'; did you mean 'destroy_compress_ctx'?
     .destroy_decompress_ctx = zstd_destroy_decompress_ctx,
      ^~~~~~~~~~~~~~~~~~~~~~
      destroy_compress_ctx
   fs/f2fs/compress.c:451:28: error: positional initialization of field in 'struct' declared with 'designated_init' attribute [-Werror=designated-init]
     .destroy_decompress_ctx = zstd_destroy_decompress_ctx,
                               ^~~~~~~~~~~~~~~~~~~~~~~~~~~
   fs/f2fs/compress.c:451:28: note: (near initialization for 'f2fs_zstd_ops')
   fs/f2fs/compress.c:451:28: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
   fs/f2fs/compress.c:451:28: note: (near initialization for 'f2fs_zstd_ops.decompress_pages')
   cc1: some warnings being treated as errors

vim +450 fs/f2fs/compress.c

   445	
   446	static const struct f2fs_compress_ops f2fs_zstd_ops = {
   447		.init_compress_ctx	= zstd_init_compress_ctx,
   448		.destroy_compress_ctx	= zstd_destroy_compress_ctx,
   449		.compress_pages		= zstd_compress_pages,
 > 450		.init_decompress_ctx	= zstd_init_decompress_ctx,
   451		.destroy_decompress_ctx	= zstd_destroy_decompress_ctx,
   452		.decompress_pages	= zstd_decompress_pages,
   453	};
   454	#endif
   455	

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