new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index b785e77..3f1128b 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -273,7 +273,7 @@
 {
 	if (!pipe->f_op || !pipe->f_op->write)
 		return -EINVAL;
-	if (!S_ISFIFO(pipe->f_dentry->d_inode->i_mode))
+	if (!S_ISFIFO(file_inode(pipe)->i_mode))
 		return -EINVAL;
 	/* We want a packet pipe */
 	pipe->f_flags |= O_DIRECT;
diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index 9f68a37..743c7c2 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -159,7 +159,7 @@
 	struct inode *inode;
 
 	if (f) {
-		inode = f->f_path.dentry->d_inode;
+		inode = file_inode(f);
 		sbi = autofs4_sbi(inode->i_sb);
 	}
 	return sbi;
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index c934476..3cdf835 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -874,7 +874,7 @@
 static long autofs4_root_ioctl(struct file *filp,
 			       unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	return autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
 }
 
@@ -882,7 +882,7 @@
 static long autofs4_root_compat_ioctl(struct file *filp,
 			     unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	int ret;
 
 	if (cmd == AUTOFS_IOC_READY || cmd == AUTOFS_IOC_FAIL)