Re: [f2fs-dev] [PATCH 2/2] f2fs: report # of free inodes more precisely

[Jaegeuk Kim]

On 06/26, Chao Yu wrote:
> Hi Jaegeuk,
> 
> On 2017/6/25 0:25, Jaegeuk Kim wrote:
> > If the partition is small, we don't need to report total # of inodes including
> > hidden free nodes.
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> >  fs/f2fs/super.c | 14 +++++++++++---
> >  1 file changed, 11 insertions(+), 3 deletions(-)
> > 
> > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > index 8e39b850bfc0..3da6fb276f8b 100644
> > --- a/fs/f2fs/super.c
> > +++ b/fs/f2fs/super.c
> > @@ -680,6 +680,7 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
> >  	struct f2fs_sb_info *sbi = F2FS_SB(sb);
> >  	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
> >  	block_t total_count, user_block_count, start_count, ovp_count;
> > +	u64 avail_node_count;
> >  
> >  	total_count = le64_to_cpu(sbi->raw_super->block_count);
> >  	user_block_count = sbi->user_block_count;
> > @@ -692,9 +693,16 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
> >  	buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
> >  	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
> >  
> > -	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
> > -	buf->f_ffree = min(buf->f_files - valid_node_count(sbi),
> > -							buf->f_bavail);
> > +	avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
> > +
> > +	if (avail_node_count > user_block_count) {
> > +		buf->f_files = user_block_count;
> > +		buf->f_ffree = buf->f_bavail;
> 
> f_ffree is limited both by remained free nid count and free block count, so it
> needs to change like this?

I thought both of them are same, since node block will consume user block. So,
we don't need to do min() again.

> 
> if (avail_node_count > user_block_count)
> 	avail_node_count = user_block_count;
> 
> buf->f_files = avail_node_count;
> buf->f_ffree = min(avail_node_count - valid_node_count(sbi),
> 					buf->f_bavail);
> 
> Thanks,
> 
> > +	} else {
> > +		buf->f_files = avail_node_count;
> > +		buf->f_ffree = min(avail_node_count - valid_node_count(sbi),
> > +					buf->f_bavail);
> > +	}
> >  
> >  	buf->f_namelen = F2FS_NAME_LEN;
> >  	buf->f_fsid.val[0] = (u32)id;
> >