[akpm-mm:mm-unstable 166/172] include/linux/memfd.h:27:5: warning: no previous prototype for 'memfd_check_seals_mmap'

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
head:   6e165f54437931f329d09dca6c19d99af08a36e1
commit: 6b72648c4e2b94fc7df65cab28a59b185a37c997 [166/172] mm: perform all memfd seal checks in a single place
config: arc-randconfig-001-20241207 (https://download.01.org/0day-ci/archive/20241207/202412072138.KfHWCUZe-lkp@intel.com/config)
compiler: arceb-elf-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241207/202412072138.KfHWCUZe-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412072138.KfHWCUZe-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from mm/gup.c:8:
>> include/linux/memfd.h:27:5: warning: no previous prototype for 'memfd_check_seals_mmap' [-Wmissing-prototypes]
      27 | int memfd_check_seals_mmap(struct file *file, unsigned long *vm_flags)
         |     ^~~~~~~~~~~~~~~~~~~~~~


vim +/memfd_check_seals_mmap +27 include/linux/memfd.h

     6	
     7	#ifdef CONFIG_MEMFD_CREATE
     8	extern long memfd_fcntl(struct file *file, unsigned int cmd, unsigned int arg);
     9	struct folio *memfd_alloc_folio(struct file *memfd, pgoff_t idx);
    10	/*
    11	 * Check for any existing seals on mmap, return an error if access is denied due
    12	 * to sealing, or 0 otherwise.
    13	 *
    14	 * We also update VMA flags if appropriate by manipulating the VMA flags pointed
    15	 * to by vm_flags_ptr.
    16	 */
    17	int memfd_check_seals_mmap(struct file *file, unsigned long *vm_flags_ptr);
    18	#else
    19	static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned int a)
    20	{
    21		return -EINVAL;
    22	}
    23	static inline struct folio *memfd_alloc_folio(struct file *memfd, pgoff_t idx)
    24	{
    25		return ERR_PTR(-EINVAL);
    26	}
  > 27	int memfd_check_seals_mmap(struct file *file, unsigned long *vm_flags)
    28	{
    29		return 0;
    30	}
    31	#endif
    32	

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