lkml.org 
[lkml]   [2018]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 11/28] ovl: Add helper ovl_dentry_lowerdata() to get lower data dentry
Date
From: Vivek Goyal <vgoyal@redhat.com>

Now we have the notion of data dentry and metacopy dentry.
ovl_dentry_lower() will return uppermost lower dentry, but it could be
either data or metacopy 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@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
fs/overlayfs/overlayfs.h | 1 +
fs/overlayfs/util.c | 13 +++++++++++++
2 files changed, 14 insertions(+)

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 31795c041d61..13b2151cf4df 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -221,6 +221,7 @@ 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 ovl_layer *ovl_layer_lower(struct dentry *dentry);
struct dentry *ovl_dentry_real(struct dentry *dentry);
struct dentry *ovl_i_dentry_upper(struct inode *inode);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 32ff67fa0bfb..7c7b95d5da1f 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -207,6 +207,19 @@ struct ovl_layer *ovl_layer_lower(struct dentry *dentry)
return oe->numlower ? oe->lowerstack[0].layer : 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 dentry). This helper
+ * returns the lower data dentry.
+ */
+struct dentry *ovl_dentry_lowerdata(struct dentry *dentry)
+{
+ struct ovl_entry *oe = dentry->d_fsdata;
+
+ return oe->numlower ? oe->lowerstack[oe->numlower - 1].dentry : NULL;
+}
+
struct dentry *ovl_dentry_real(struct dentry *dentry)
{
return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry);
--
2.14.3
\
 
 \ /
  Last update: 2018-05-29 16:56    [W:0.183 / U:0.032 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site