From: Eric W. Biederman <ebiederm@xmission.com>
Date: Tue, 25 Feb 2014 01:32:34 +0000 (-0800)
Subject: vfs: factor out lookup_mountpoint from new_mountpoint
X-Git-Tag: next-20140428~9^2~11
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d5d3708a0f57a7f3a237c84c213232a8145352a9;p=karo-tx-linux.git

vfs: factor out lookup_mountpoint from new_mountpoint

I am shortly going to add a new user of struct mountpoint that
needs to look up existing entries but does not want to create
a struct mountpoint if one does not exist.  Therefore to keep
the code simple and easy to read split out lookup_mountpoint
from new_mountpoint.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---

diff --git a/fs/namespace.c b/fs/namespace.c
index 32d380eabdac..f2f03082fe70 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -667,11 +667,10 @@ out:
 	return is_covered;
 }
 
-static struct mountpoint *new_mountpoint(struct dentry *dentry)
+static struct mountpoint *lookup_mountpoint(struct dentry *dentry)
 {
 	struct list_head *chain = mountpoint_hashtable + hash(NULL, dentry);
 	struct mountpoint *mp;
-	int ret;
 
 	list_for_each_entry(mp, chain, m_hash) {
 		if (mp->m_dentry == dentry) {
@@ -682,6 +681,14 @@ static struct mountpoint *new_mountpoint(struct dentry *dentry)
 			return mp;
 		}
 	}
+	return NULL;
+}
+
+static struct mountpoint *new_mountpoint(struct dentry *dentry)
+{
+	struct list_head *chain = mountpoint_hashtable + hash(NULL, dentry);
+	struct mountpoint *mp;
+	int ret;
 
 	mp = kmalloc(sizeof(struct mountpoint), GFP_KERNEL);
 	if (!mp)
@@ -1702,7 +1709,9 @@ retry:
 	namespace_lock();
 	mnt = lookup_mnt(path);
 	if (likely(!mnt)) {
-		struct mountpoint *mp = new_mountpoint(dentry);
+		struct mountpoint *mp = lookup_mountpoint(dentry);
+		if (!mp)
+			mp = new_mountpoint(dentry);
 		if (IS_ERR(mp)) {
 			namespace_unlock();
 			mutex_unlock(&dentry->d_inode->i_mutex);