Re: [PATCH] staging: erofs: fix undeclared symbols

[Gao Xiang <hsiangkao@aol.com>]

Hi Thomas,

On 2018/9/21 2:58, Thomas Weißschuh wrote:
> Move all internal symbols to the internal header file and add a missing
> "static" declaration.
> This fixes the sparse warnings like the following:
> 
> drivers/staging/erofs/unzip_lz4.c:230:5: warning: symbol 'z_erofs_unzip_lz4' was not declared. Should it be static?
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
>  drivers/staging/erofs/data.c          |  5 -----
>  drivers/staging/erofs/internal.h      | 14 ++++++++++++++
>  drivers/staging/erofs/super.c         |  5 -----
>  drivers/staging/erofs/unzip_vle.c     |  2 +-
>  drivers/staging/erofs/unzip_vle_lz4.c |  2 --
>  drivers/staging/erofs/utils.c         |  2 --
>  6 files changed, 15 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/staging/erofs/data.c b/drivers/staging/erofs/data.c
> index ac263a180253..9bfcc549bbf0 100644
> --- a/drivers/staging/erofs/data.c
> +++ b/drivers/staging/erofs/data.c
> @@ -137,11 +137,6 @@ static int erofs_map_blocks_flatmode(struct inode *inode,
>  	return 0;
>  }
>  
> -#ifdef CONFIG_EROFS_FS_ZIP
> -extern int z_erofs_map_blocks_iter(struct inode *,
> -	struct erofs_map_blocks *, struct page **, int);
> -#endif
> -
>  int erofs_map_blocks_iter(struct inode *inode,
>  	struct erofs_map_blocks *map,
>  	struct page **mpage_ret, int flags)
> diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
> index 367b39fe46e5..d4c4c87bcd35 100644
> --- a/drivers/staging/erofs/internal.h
> +++ b/drivers/staging/erofs/internal.h
> @@ -547,6 +547,20 @@ extern unsigned long erofs_shrink_count(struct shrinker *shrink,
>  	struct shrink_control *sc);
>  extern unsigned long erofs_shrink_scan(struct shrinker *shrink,
>  	struct shrink_control *sc);
> +extern void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
> +
> +#ifdef CONFIG_EROFS_FS_ZIP
> +/* super.c */
> +extern int z_erofs_init_zip_subsystem(void);
> +extern void z_erofs_exit_zip_subsystem(void);
> +
> +/* unzip_vle.c */
> +extern int z_erofs_map_blocks_iter(struct inode *,
> +	struct erofs_map_blocks *, struct page **, int);
> +
> +/* unzip_lz4.c */
> +extern int z_erofs_unzip_lz4(void *in, void *out, size_t inlen, size_t outlen);

Thanks for your patch.

Here z_erofs_unzip_lz4 couldn't be directly declared in internal.h
   --- internal.h means the file system internal but not for the decompression algorithms.
 
Some declarations in *.c are for temporary use.
z_erofs_unzip_lz4 has no related with the file system itself and I planned to cleanup later
after we have more decompression algorithm support such as zstd....

If you want to cleanup now, prefer to introduce "decompressor wrappers" and a new .h
rather than cleanup as simple as what is done in this commit.

> +#endif
>  
>  #ifndef lru_to_page
>  #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
> diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
> index 2df9768edac9..c41d92e0cb3c 100644
> --- a/drivers/staging/erofs/super.c
> +++ b/drivers/staging/erofs/super.c
> @@ -521,11 +521,6 @@ static struct file_system_type erofs_fs_type = {
>  };
>  MODULE_ALIAS_FS("erofs");
>  
> -#ifdef CONFIG_EROFS_FS_ZIP
> -extern int z_erofs_init_zip_subsystem(void);
> -extern void z_erofs_exit_zip_subsystem(void);
> -#endif
> -
>  static int __init erofs_module_init(void)
>  {
>  	int err;
> diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
> index 8721f0a41d15..a0d6c620051f 100644
> --- a/drivers/staging/erofs/unzip_vle.c
> +++ b/drivers/staging/erofs/unzip_vle.c
> @@ -517,7 +517,7 @@ static void __z_erofs_vle_work_release(struct z_erofs_vle_workgroup *grp,
>  	erofs_workgroup_put(&grp->obj);
>  }
>  
> -void z_erofs_vle_work_release(struct z_erofs_vle_work *work)
> +static void z_erofs_vle_work_release(struct z_erofs_vle_work *work)
>  {
>  	struct z_erofs_vle_workgroup *grp =
>  		z_erofs_vle_work_workgroup(work, true);

How about making a separate patch to fix all the missing `static's?
Or How about changing your patch title "staging: erofs: fix undeclared symbols"
to indicate you also add some missing `static's ?

Thanks,
Gao Xiang

> diff --git a/drivers/staging/erofs/unzip_vle_lz4.c b/drivers/staging/erofs/unzip_vle_lz4.c
> index f5b665f15be5..e30e6e2ef05b 100644
> --- a/drivers/staging/erofs/unzip_vle_lz4.c
> +++ b/drivers/staging/erofs/unzip_vle_lz4.c
> @@ -99,8 +99,6 @@ int z_erofs_vle_plain_copy(struct page **compressed_pages,
>  	return 0;
>  }
>  
> -extern int z_erofs_unzip_lz4(void *in, void *out, size_t inlen, size_t outlen);
> -
>  int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages,
>  				  unsigned clusterpages,
>  				  struct page **pages,
> diff --git a/drivers/staging/erofs/utils.c b/drivers/staging/erofs/utils.c
> index 595cf90af9bb..26b9f97f258a 100644
> --- a/drivers/staging/erofs/utils.c
> +++ b/drivers/staging/erofs/utils.c
> @@ -99,8 +99,6 @@ int erofs_register_workgroup(struct super_block *sb,
>  	return err;
>  }
>  
> -extern void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
> -
>  int erofs_workgroup_put(struct erofs_workgroup *grp)
>  {
>  	int count = atomic_dec_return(&grp->refcount);
>