new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c
index df1a7fb..f30b017 100644
--- a/fs/nilfs2/dir.c
+++ b/fs/nilfs2/dir.c
@@ -259,7 +259,7 @@
 static int nilfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 {
 	loff_t pos = filp->f_pos;
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	struct super_block *sb = inode->i_sb;
 	unsigned int offset = pos & ~PAGE_CACHE_MASK;
 	unsigned long n = pos >> PAGE_CACHE_SHIFT;
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index 6194688..89dc088 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -67,7 +67,7 @@
 static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct page *page = vmf->page;
-	struct inode *inode = vma->vm_file->f_dentry->d_inode;
+	struct inode *inode = file_inode(vma->vm_file);
 	struct nilfs_transaction_info ti;
 	int ret = 0;
 
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index fdb1807..ef61c74 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -793,7 +793,7 @@
 
 long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	void __user *argp = (void __user *)arg;
 
 	switch (cmd) {