cache the value of file_inode() in struct file

Note that this thing does *not* contribute to inode refcount;
it's pinned down by dentry.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/file_table.c b/fs/file_table.c
index aa07d3684a2e..cd4d87a82951 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -176,6 +176,7 @@ struct file *alloc_file(struct path *path, fmode_t mode,
                 return file;
 
         file->f_path = *path;
+        file->f_inode = path->dentry->d_inode;
         file->f_mapping = path->dentry->d_inode->i_mapping;
         file->f_mode = mode;
         file->f_op = fop;
@@ -258,6 +259,7 @@ static void __fput(struct file *file)
                 drop_file_write_access(file);
         file->f_path.dentry = NULL;
         file->f_path.mnt = NULL;
+        file->f_inode = NULL;
         file_free(file);
         dput(dentry);
         mntput(mnt);