On Fri, Apr 12, 2024 at 5:01 PM Stefan Berger <stefanb@xxxxxxxxxxxxx> wrote:
>
> Define D_REAL_FILEDATA which is to be used as a parameter for d_real()
> to return the dentry that is holding the file data, which is either the
D_REAL_DATA already does that
> upper or the lower denry. The caller is expected to call d_real() again
> on the returned dentry to get to lower layers of a stacked filesystem,
> if available.
>
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> ---
> fs/overlayfs/super.c | 6 ++++++
> include/linux/dcache.h | 1 +
> 2 files changed, 7 insertions(+)
>
> diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
> index 06a231970cb5..f466ad89b005 100644
> --- a/fs/overlayfs/super.c
> +++ b/fs/overlayfs/super.c
> @@ -36,6 +36,7 @@ static struct dentry *ovl_d_real(struct dentry *dentry, enum d_real_type type)
> switch (type) {
> case D_REAL_DATA:
> case D_REAL_METADATA:
> + case D_REAL_FILEDATA:
> break;
> default:
> goto bug;
> @@ -47,6 +48,11 @@ static struct dentry *ovl_d_real(struct dentry *dentry, enum d_real_type type)
> }
>
> upper = ovl_dentry_upper(dentry);
> + if (type == D_REAL_FILEDATA) {
> + if (ovl_has_upperdata(d_inode(dentry)))
> + return upper;
This one is already the returned value for D_REAL_DATA
> + return ovl_dentry_lower(dentry);
And this one is a wrong value, because the lower file's data is at
ovl_dentry_lowerdata(), which is what D_REAL_DATA
returns.
So it is not clear to me what it is that you tried to do here.
Thanks,
Amir.
