Re: [PATCH] bcache: Use bcache without formatting existing device

[kernel test robot <lkp@xxxxxxxxx>]

Hi Andrea,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v5.17-rc7 next-20220309]
[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/Andrea-Tomassetti/bcache-Use-bcache-without-formatting-existing-device/20220310-165353
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 3bf7edc84a9eb4007dd9a0cb8878a7e1d5ec6a3b
config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220310/202203101939.OFoiVCSH-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Ubuntu 9.4.0-1ubuntu1~20.04) 9.4.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/b5073e4ece2a86f002ca66fb1d864034c12be3e2
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Andrea-Tomassetti/bcache-Use-bcache-without-formatting-existing-device/20220310-165353
        git checkout b5073e4ece2a86f002ca66fb1d864034c12be3e2
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/md/bcache/

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

All warnings (new ones prefixed by >>):

>> drivers/md/bcache/control.c:18:6: warning: no previous prototype for 'bch_service_ioctl_ctrl' [-Wmissing-prototypes]
      18 | long bch_service_ioctl_ctrl(struct file *filp, unsigned int cmd,
         |      ^~~~~~~~~~~~~~~~~~~~~~


vim +/bch_service_ioctl_ctrl +18 drivers/md/bcache/control.c

    15	
    16	/* this handles IOCTL for /dev/bcache_ctrl */
    17	/*********************************************/
  > 18	long bch_service_ioctl_ctrl(struct file *filp, unsigned int cmd,
    19			unsigned long arg)
    20	{
    21		int retval = 0;
    22	
    23		if (_IOC_TYPE(cmd) != BCH_IOCTL_MAGIC)
    24			return -EINVAL;
    25	
    26		if (!capable(CAP_SYS_ADMIN)) {
    27			/* Must be root to issue ioctls */
    28			return -EPERM;
    29		}
    30	
    31		switch (cmd) {
    32		case BCH_IOCTL_REGISTER_DEVICE: {
    33			struct bch_register_device *cmd_info;
    34	
    35			cmd_info = vmalloc(sizeof(struct bch_register_device));
    36			if (!cmd_info)
    37				return -ENOMEM;
    38	
    39			if (copy_from_user(cmd_info, (void __user *)arg,
    40					sizeof(struct bch_register_device))) {
    41				pr_err("Cannot copy cmd info from user space\n");
    42				vfree(cmd_info);
    43				return -EINVAL;
    44			}
    45	
    46			retval = register_bcache_ioctl(cmd_info);
    47	
    48			vfree(cmd_info);
    49			return retval;
    50		}
    51	
    52		default:
    53			return -EINVAL;
    54		}
    55	}
    56	

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0-DAY CI Kernel Test Service, Intel Corporation
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