[JFFS2] Quiet lockdep false positive.

Don't hold f->sem while calling into jffs2_do_create(). It makes lockdep
unhappy, and we don't really need it -- the _reason_ it's a false
positive is because nobody else can see this inode yet and so nobody
will be trying to lock it anyway.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
index c63e7a96af0..2bba3d3435b 100644
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -208,6 +208,13 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry, int mode,
         f = JFFS2_INODE_INFO(inode);
         dir_f = JFFS2_INODE_INFO(dir_i);
 
+        /* jffs2_do_create() will want to lock it, _after_ reserving
+           space and taking c-alloc_sem. If we keep it locked here,
+           lockdep gets unhappy (although it's a false positive;
+           nothing else will be looking at this inode yet so there's
+           no chance of AB-BA deadlock involving its f->sem). */
+        mutex_unlock(&f->sem);
+
         ret = jffs2_do_create(c, dir_f, f, ri,
                               dentry->d_name.name, dentry->d_name.len);
         if (ret)