wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 97a563b..3629444 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -630,10 +630,10 @@
 		goto bail;
 	}
 
-	mutex_lock(&inode_alloc_inode->i_mutex);
+	inode_lock(inode_alloc_inode);
 	status = ocfs2_inode_lock(inode_alloc_inode, &inode_alloc_bh, 1);
 	if (status < 0) {
-		mutex_unlock(&inode_alloc_inode->i_mutex);
+		inode_unlock(inode_alloc_inode);
 
 		mlog_errno(status);
 		goto bail;
@@ -680,7 +680,7 @@
 	ocfs2_commit_trans(osb, handle);
 bail_unlock:
 	ocfs2_inode_unlock(inode_alloc_inode, 1);
-	mutex_unlock(&inode_alloc_inode->i_mutex);
+	inode_unlock(inode_alloc_inode);
 	brelse(inode_alloc_bh);
 bail:
 	iput(inode_alloc_inode);
@@ -751,10 +751,10 @@
 		/* Lock the orphan dir. The lock will be held for the entire
 		 * delete_inode operation. We do this now to avoid races with
 		 * recovery completion on other nodes. */
-		mutex_lock(&orphan_dir_inode->i_mutex);
+		inode_lock(orphan_dir_inode);
 		status = ocfs2_inode_lock(orphan_dir_inode, &orphan_dir_bh, 1);
 		if (status < 0) {
-			mutex_unlock(&orphan_dir_inode->i_mutex);
+			inode_unlock(orphan_dir_inode);
 
 			mlog_errno(status);
 			goto bail;
@@ -803,7 +803,7 @@
 		return status;
 
 	ocfs2_inode_unlock(orphan_dir_inode, 1);
-	mutex_unlock(&orphan_dir_inode->i_mutex);
+	inode_unlock(orphan_dir_inode);
 	brelse(orphan_dir_bh);
 bail:
 	iput(orphan_dir_inode);