Re: [RFC][PATCH v2 05/10] exofs: use common file type conversion

[Boaz Harrosh]

On 23/10/18 23:19, Phillip Potter wrote:
> Deduplicate the exofs file type conversion implementation.
> 
> Original patch by Amir Goldstein.
> 
> v2:
> - This version does not remove EXOFS_FT_x enum from fs/exofs/common.h,
>   as these values are now used in compile-time checks added by
>   Phillip Potter to make sure they remain the same as FT_x values
> 
> v1:
> - Initial implementation
> 
> Signed-off-by: Phillip Potter <phil@xxxxxxxxxxxxxxxx>

Yes thank you, totally

ACK-by: Boaz Harrosh <ooo@xxxxxxxxxxxxxxx>

> ---
>  fs/exofs/dir.c | 49 ++++++++++++++++++-------------------------------
>  1 file changed, 18 insertions(+), 31 deletions(-)
> 
> diff --git a/fs/exofs/dir.c b/fs/exofs/dir.c
> index f0138674c1ed..2e3161ca9014 100644
> --- a/fs/exofs/dir.c
> +++ b/fs/exofs/dir.c
> @@ -204,33 +204,10 @@ exofs_validate_entry(char *base, unsigned offset, unsigned mask)
>  	return (char *)p - base;
>  }
>  
> -static unsigned char exofs_filetype_table[EXOFS_FT_MAX] = {
> -	[EXOFS_FT_UNKNOWN]	= DT_UNKNOWN,
> -	[EXOFS_FT_REG_FILE]	= DT_REG,
> -	[EXOFS_FT_DIR]		= DT_DIR,
> -	[EXOFS_FT_CHRDEV]	= DT_CHR,
> -	[EXOFS_FT_BLKDEV]	= DT_BLK,
> -	[EXOFS_FT_FIFO]		= DT_FIFO,
> -	[EXOFS_FT_SOCK]		= DT_SOCK,
> -	[EXOFS_FT_SYMLINK]	= DT_LNK,
> -};
> -
> -#define S_SHIFT 12
> -static unsigned char exofs_type_by_mode[S_IFMT >> S_SHIFT] = {
> -	[S_IFREG >> S_SHIFT]	= EXOFS_FT_REG_FILE,
> -	[S_IFDIR >> S_SHIFT]	= EXOFS_FT_DIR,
> -	[S_IFCHR >> S_SHIFT]	= EXOFS_FT_CHRDEV,
> -	[S_IFBLK >> S_SHIFT]	= EXOFS_FT_BLKDEV,
> -	[S_IFIFO >> S_SHIFT]	= EXOFS_FT_FIFO,
> -	[S_IFSOCK >> S_SHIFT]	= EXOFS_FT_SOCK,
> -	[S_IFLNK >> S_SHIFT]	= EXOFS_FT_SYMLINK,
> -};
> -
>  static inline
>  void exofs_set_de_type(struct exofs_dir_entry *de, struct inode *inode)
>  {
> -	umode_t mode = inode->i_mode;
> -	de->file_type = exofs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
> +	de->file_type = fs_umode_to_ftype(inode->i_mode);
>  }
>  
>  static int
> @@ -279,17 +256,27 @@ exofs_readdir(struct file *file, struct dir_context *ctx)
>  				exofs_put_page(page);
>  				return -EIO;
>  			}
> -			if (de->inode_no) {
> -				unsigned char t;
>  
> -				if (de->file_type < EXOFS_FT_MAX)
> -					t = exofs_filetype_table[de->file_type];
> -				else
> -					t = DT_UNKNOWN;
> +			/*
> +			 * compile-time asserts that generic FT_x types
> +			 * still match EXOFS_FT_x types - no need to list
> +			 * for other functions as well as build will
> +			 * fail either way
> +			 */
> +			BUILD_BUG_ON(EXOFS_FT_UNKNOWN != FT_UNKNOWN);
> +			BUILD_BUG_ON(EXOFS_FT_REG_FILE != FT_REG_FILE);
> +			BUILD_BUG_ON(EXOFS_FT_DIR != FT_DIR);
> +			BUILD_BUG_ON(EXOFS_FT_CHRDEV != FT_CHRDEV);
> +			BUILD_BUG_ON(EXOFS_FT_BLKDEV != FT_BLKDEV);
> +			BUILD_BUG_ON(EXOFS_FT_FIFO != FT_FIFO);
> +			BUILD_BUG_ON(EXOFS_FT_SOCK != FT_SOCK);
> +			BUILD_BUG_ON(EXOFS_FT_SYMLINK != FT_SYMLINK);
> +			BUILD_BUG_ON(EXOFS_FT_MAX != FT_MAX);
>  
> +			if (de->inode_no) {
>  				if (!dir_emit(ctx, de->name, de->name_len,
>  						le64_to_cpu(de->inode_no),
> -						t)) {
> +						fs_dtype(de->file_type))) {
>  					exofs_put_page(page);
>  					return 0;
>  				}
>