Re: [PATCH 1/1] f2fs: merge equivalent flags F2FS_GET_BLOCK_[READ|DIO]

[Sun Qiuyang]

> On 2017/8/8 18:27, sunqiuyang wrote:
> > From: Qiuyang Sun <sunqiuyang@xxxxxxxxxx>
> >
> > Currently, the two flags F2FS_GET_BLOCK_[READ|DIO] are totally equivalent
> > and can be used interchangably in all scenarios they are involved in. This
> > patch deletes F2FS_GET_BLOCK_READ and uses F2FS_GET_BLOCK_DIO instead.
>
> Seems weird from readability point of view, so how about keeping
> F2FS_GET_BLOCK_READ alive but sharing defined value with F2FS_GET_BLOCK_DIO?
>
> enum {
> 	F2FS_GET_BLOCK_DIO,
> 	F2FS_GET_BLOCK_READ = F2FS_GET_BLOCK_DIO,
> 	F2FS_GET_BLOCK_FIEMAP,
> 	...
> }
>
> Thanks,
How about renaming both of them F2FS_GET_BLOCK_DEFAULT? Actually neither 
READ nor DIO is explicitly referenced in f2fs_map_blocks(); it is just 
the "default" case. We have no reason to limit the use of this flag to 
"read" or "direct IO" only.

Thanks,
> > Signed-off-by: Qiuyang Sun <sunqiuyang@xxxxxxxxxx>
> > ---
> >  fs/f2fs/data.c | 2 +-
> >  fs/f2fs/f2fs.h | 1 -
> >  fs/f2fs/file.c | 4 ++--
> >  3 files changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index c43262d..e0a59bf 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -1244,7 +1244,7 @@ static int f2fs_mpage_readpages(struct address_space *mapping,
> >  			map.m_len = last_block - block_in_file;
> >
> >  			if (f2fs_map_blocks(inode, &map, 0,
> > -						F2FS_GET_BLOCK_READ))
> > +						F2FS_GET_BLOCK_DIO))
> >  				goto set_error_page;
> >  		}
> >  got_it:
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index cea329f..0593ca7 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -514,7 +514,6 @@ struct f2fs_map_blocks {
> >  };
> >
> >  /* for flag in get_data_block */
> > -#define F2FS_GET_BLOCK_READ		0
> >  #define F2FS_GET_BLOCK_DIO		1
> >  #define F2FS_GET_BLOCK_FIEMAP		2
> >  #define F2FS_GET_BLOCK_BMAP		3
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index e2b33b8..8271cb5 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -2074,7 +2074,7 @@ static int f2fs_defragment_range(struct f2fs_sb_info *sbi,
> >  	 */
> >  	while (map.m_lblk < pg_end) {
> >  		map.m_len = pg_end - map.m_lblk;
> > -		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_READ);
> > +		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DIO);
> >  		if (err)
> >  			goto out;
> >
> > @@ -2116,7 +2116,7 @@ static int f2fs_defragment_range(struct f2fs_sb_info *sbi,
> >
> >  do_map:
> >  		map.m_len = pg_end - map.m_lblk;
> > -		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_READ);
> > +		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DIO);
> >  		if (err)
> >  			goto clear_out;
>
>
> .