fs: dlm: move dlm_purge_lkb_callbacks to user module

This patch moves the dlm_purge_lkb_callbacks() function from ast to user
dlm module as it is only a function being used by dlm user
implementation. I got be hinted to hold specific locks regarding the
callback handling for dlm_purge_lkb_callbacks() but it was false
positive. It is confusing because ast dlm implementation uses a
different locking behaviour as user locks uses as DLM handles kernel and
user dlm locks differently. To avoid the confusing we move this function
to dlm user implementation.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index d9c09fc0aba1..695e691b38b3 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -145,6 +145,24 @@ static void compat_output(struct dlm_lock_result *res,
 }
 #endif
 
+/* should held proc->asts_spin lock */
+void dlm_purge_lkb_callbacks(struct dlm_lkb *lkb)
+{
+	struct dlm_callback *cb, *safe;
+
+	list_for_each_entry_safe(cb, safe, &lkb->lkb_callbacks, list) {
+		list_del(&cb->list);
+		kref_put(&cb->ref, dlm_release_callback);
+	}
+
+	clear_bit(DLM_IFL_CB_PENDING_BIT, &lkb->lkb_iflags);
+
+	/* invalidate */
+	dlm_callback_set_last_ptr(&lkb->lkb_last_cast, NULL);
+	dlm_callback_set_last_ptr(&lkb->lkb_last_cb, NULL);
+	lkb->lkb_last_bast_mode = -1;
+}
+
 /* Figure out if this lock is at the end of its life and no longer
    available for the application to use.  The lkb still exists until
    the final ast is read.  A lock becomes EOL in three situations: