[PATCH v2 1/2] smb/client: use d_time to store a timestamp in dentry, not d_fsdata

From: NeilBrown <[email protected]>

smb/client uses d_fsdata is exactly the way that d_time is intended to
be used.  It previous used d_time but this was changed in
  Commit: a00be0e31f8d ("cifs: don't use ->d_time")
without any reason being given.

This patch effectively reverts that patch (though it doesn't remove the
helpers) so that d_fsdata can be used for something more generic.

As ->d_time is NOT initialised by d_alloc() (unlike ->d_fsdata), it is
important to initialise it in atomic_open (all dentries go through
either ->lookup or ->atomic_open before being hashed, and both of these
now initialise ->d_time).

Cc: Miklos Szeredi <[email protected]>
Signed-off-by: NeilBrown <[email protected]>
---
 fs/smb/client/cifsfs.h | 4 ++--
 fs/smb/client/dir.c    | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/cifsfs.h b/fs/smb/client/cifsfs.h
index 901e1340c986..e489aaf206b2 100644
--- a/fs/smb/client/cifsfs.h
+++ b/fs/smb/client/cifsfs.h
@@ -34,12 +34,12 @@ cifs_uniqueid_to_ino_t(u64 fileid)
 
 static inline void cifs_set_time(struct dentry *dentry, unsigned long time)
 {
-	dentry->d_fsdata = (void *) time;
+	dentry->d_time = time;
 }
 
 static inline unsigned long cifs_get_time(struct dentry *dentry)
 {
-	return (unsigned long) dentry->d_fsdata;
+	return dentry->d_time;
 }
 
 extern struct file_system_type cifs_fs_type, smb3_fs_type;
diff --git a/fs/smb/client/dir.c b/fs/smb/client/dir.c
index 88a4a1787ff0..bd9684b61c2b 100644
--- a/fs/smb/client/dir.c
+++ b/fs/smb/client/dir.c
@@ -598,6 +598,7 @@ int cifs_atomic_open(struct inode *dir, struct dentry *direntry,
 	} else {
 		d_instantiate(direntry, inode);
 	}
+	cifs_set_time(direntry, jiffies);
 
 	if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 		file->f_mode |= FMODE_CREATED;
-- 
2.50.0.107.gf914562f5916.dirty