On Thu, Mar 29, 2018 at 10:38 PM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:
> Now we have the notion of data dentry and metacopy dentry. ovl_dentry_lower()
> will return lower dentry at idx 0, but it could be either data or metacopy
will return the upper most lower dentry. (idx 0 means upper).
> dentry. Now we support metacopy dentries in lower layers so it is possible
> that lowerstack[0] is metacopy dentry while lowerstack[1] is actual data
> dentry.
>
> So add an helper which returns lowest most dentry which is supposed to be
> data dentry.
>
> Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> fs/overlayfs/overlayfs.h | 1 +
> fs/overlayfs/util.c | 14 ++++++++++++++
> 2 files changed, 15 insertions(+)
>
> diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
> index 4eb4b765887f..214d9f08c574 100644
> --- a/fs/overlayfs/overlayfs.h
> +++ b/fs/overlayfs/overlayfs.h
> @@ -226,6 +226,7 @@ void ovl_path_lowerdata(struct dentry *dentry, struct path *path);
> enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
> struct dentry *ovl_dentry_upper(struct dentry *dentry);
> struct dentry *ovl_dentry_lower(struct dentry *dentry);
> +struct dentry *ovl_dentry_lowerdata(struct dentry *dentry);
> struct dentry *ovl_dentry_real(struct dentry *dentry);
> struct dentry *ovl_i_dentry_upper(struct inode *inode);
> struct inode *ovl_inode_upper(struct inode *inode);
> diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
> index fd98329e820c..394674c4c820 100644
> --- a/fs/overlayfs/util.c
> +++ b/fs/overlayfs/util.c
> @@ -186,6 +186,20 @@ struct dentry *ovl_dentry_lower(struct dentry *dentry)
> return oe->numlower ? oe->lowerstack[0].dentry : NULL;
> }
>
> +/*
> + * ovl_dentry_lower() could return either a data dentry or metacopy dentry
> + * dependig on what is stored in lowerstack[0]. At times we need to find
> + * lower dentry which has data (and not metacopy dntry). This helper
> + * returns the lower data dentry.
> + */
> +struct dentry *ovl_dentry_lowerdata(struct dentry *dentry)
> +{
> + struct ovl_entry *oe = dentry->d_fsdata;
> + int idx = oe->numlower - 1;
Please stick with convention of layer->idx that idx 0 is upper.
> +
> + return idx >= 0 ? oe->lowerstack[idx].dentry : NULL;
> +}
> +
> struct dentry *ovl_dentry_real(struct dentry *dentry)
> {
> return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry);
> --
> 2.13.6
>
--
To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
