cifs: warn about impending deprecation of legacy MultiuserMount code

We'll allow a grace period of 2 releases (3.3 and 3.4) and then remove
the legacy code in 3.5.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 84e8c0724704..24b3dfc05282 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -676,14 +676,23 @@ static ssize_t cifs_multiuser_mount_proc_write(struct file *file,
 {
         char c;
         int rc;
+        static bool warned;
 
         rc = get_user(c, buffer);
         if (rc)
                 return rc;
         if (c == '0' || c == 'n' || c == 'N')
                 multiuser_mount = 0;
-        else if (c == '1' || c == 'y' || c == 'Y')
+        else if (c == '1' || c == 'y' || c == 'Y') {
                 multiuser_mount = 1;
+                if (!warned) {
+                        warned = true;
+                        printk(KERN_WARNING "CIFS VFS: The legacy multiuser "
+                                "mount code is scheduled to be deprecated in "
+                                "3.5. Please switch to using the multiuser "
+                                "mount option.");
+                }
+        }
 
         return count;
 }