[mingo-tip:master 2294/2300] arch/mips/crypto/chacha-glue.c:45:34: error: implicit declaration of function 'round_down'

[kernel test robot]

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git master
head:   4e348e961395297bb17f101cc63bc133d8a348e9
commit: a35948847a1e0bf875f580f821cb871ce16d4c60 [2294/2300] headers/deps: time: Optimize <linux/time64.h> dependencies, remove <linux/time64_api.h> inclusion
config: mips-randconfig-r034-20220108 (https://download.01.org/0day-ci/archive/20220109/202201090259.KZeo3bGb-lkp@xxxxxxxxx/config)
compiler: mipsel-linux-gcc (GCC) 11.2.0
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/mingo/tip.git/commit/?id=a35948847a1e0bf875f580f821cb871ce16d4c60
        git remote add mingo-tip git://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git
        git fetch --no-tags mingo-tip master
        git checkout a35948847a1e0bf875f580f821cb871ce16d4c60
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=mips SHELL=/bin/bash

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

All errors (new ones prefixed by >>):

   arch/mips/crypto/chacha-glue.c: In function 'chacha_mips_stream_xor':
>> arch/mips/crypto/chacha-glue.c:45:34: error: implicit declaration of function 'round_down' [-Werror=implicit-function-declaration]
      45 |                         nbytes = round_down(nbytes, walk.stride);
         |                                  ^~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/round_down +45 arch/mips/crypto/chacha-glue.c

3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  29  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  30  static int chacha_mips_stream_xor(struct skcipher_request *req,
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  31  				  const struct chacha_ctx *ctx, const u8 *iv)
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  32  {
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  33  	struct skcipher_walk walk;
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  34  	u32 state[16];
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  35  	int err;
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  36  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  37  	err = skcipher_walk_virt(&walk, req, false);
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  38  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  39  	chacha_init_generic(state, ctx->key, iv);
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  40  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  41  	while (walk.nbytes > 0) {
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  42  		unsigned int nbytes = walk.nbytes;
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  43  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  44  		if (nbytes < walk.total)
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08 @45  			nbytes = round_down(nbytes, walk.stride);
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  46  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  47  		chacha_crypt(state, walk.dst.virt.addr, walk.src.virt.addr,
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  48  			     nbytes, ctx->nrounds);
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  49  		err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  50  	}
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  51  
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  52  	return err;
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  53  }
3a2f58f3ba4f6f Ard Biesheuvel 2019-11-08  54  

:::::: The code at line 45 was first introduced by commit
:::::: 3a2f58f3ba4f6f44e33d1a48240d5eadb882cb59 crypto: mips/chacha - wire up accelerated 32r2 code from Zinc

:::::: TO: Ard Biesheuvel <ardb@xxxxxxxxxx>
:::::: CC: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

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