[Ocfs2-devel] [PATCH] ocfs2: always read both high and low parts of dinode link count

[Joseph Qi]

On 11/27/22 2:46 PM, Alexey Asemov (Alex/AT) wrote:
> When filesystem is using indexed-dirs feature, maximum link count values
> can spill over to i_links_count_hi, up to OCFS2_DX_LINK_MAX links.
> ocfs2_read_links_count() checks for OCFS2_INDEXED_DIR_FL flag in dinode,
> but this flag is only valid for directories so for files the check
> causes high part of the link count not being read back from file
> dinodes resulting in wrong link count value when file has >65535 links.
> 
> As ocfs2_set_links_count() always writes both high and low parts of link
> count, the flag check on reading may be removed.
> 
> Signed-off-by: Alexey Asemov <alex at alex-at.net>

Reviewed-by: Joseph Qi <joseph.qi at linux.alibaba.com>
> ---
> 
>  fs/ocfs2/ocfs2.h | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
> index 740b64238312..a503c553bab2 100644
> --- a/fs/ocfs2/ocfs2.h
> +++ b/fs/ocfs2/ocfs2.h
> @@ -560,8 +560,7 @@ static inline unsigned int ocfs2_read_links_count(struct ocfs2_dinode *di)
>         u32 nlink = le16_to_cpu(di->i_links_count);
>         u32 hi = le16_to_cpu(di->i_links_count_hi);
> 
> -       if (di->i_dyn_features & cpu_to_le16(OCFS2_INDEXED_DIR_FL))
> -               nlink |= (hi << OCFS2_LINKS_HI_SHIFT);
> +       nlink |= (hi << OCFS2_LINKS_HI_SHIFT);
> 
>         return nlink;
>  }