--- /dev/null
+/******************************************************************************
+*******************************************************************************
+**
+** Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
+**
+** This copyrighted material is made available to anyone wishing to use,
+** modify, copy, or redistribute it subject to the terms and conditions
+** of the GNU General Public License v.2.
+**
+*******************************************************************************
+******************************************************************************/
+
+#include "dlm_internal.h"
+#include "member.h"
+#include "lock.h"
+#include "dir.h"
+#include "config.h"
+#include "requestqueue.h"
+
+struct rq_entry {
+ struct list_head list;
+ uint32_t recover_seq;
+ int nodeid;
+ struct dlm_message request;
+};
+
+/*
+ * Requests received while the lockspace is in recovery get added to the
+ * request queue and processed when recovery is complete. This happens when
+ * the lockspace is suspended on some nodes before it is on others, or the
+ * lockspace is enabled on some while still suspended on others.
+ */
+
+void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_message *ms)
+{
+ struct rq_entry *e;
+ int length = ms->m_header.h_length - sizeof(struct dlm_message);
+
+ e = kmalloc(sizeof(struct rq_entry) + length, GFP_NOFS);
+ if (!e) {
+ log_print("dlm_add_requestqueue: out of memory len %d", length);
+ return;
+ }
+
+ e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF;
+ e->nodeid = nodeid;
+ memcpy(&e->request, ms, ms->m_header.h_length);
+
+ mutex_lock(&ls->ls_requestqueue_mutex);
+ list_add_tail(&e->list, &ls->ls_requestqueue);
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+}
+
+/*
+ * Called by dlm_recoverd to process normal messages saved while recovery was
+ * happening. Normal locking has been enabled before this is called. dlm_recv
+ * upon receiving a message, will wait for all saved messages to be drained
+ * here before processing the message it got. If a new dlm_ls_stop() arrives
+ * while we're processing these saved messages, it may block trying to suspend
+ * dlm_recv if dlm_recv is waiting for us in dlm_wait_requestqueue. In that
+ * case, we don't abort since locking_stopped is still 0. If dlm_recv is not
+ * waiting for us, then this processing may be aborted due to locking_stopped.
+ */
+
+int dlm_process_requestqueue(struct dlm_ls *ls)
+{
+ struct rq_entry *e;
+ struct dlm_message *ms;
+ int error = 0;
+
+ mutex_lock(&ls->ls_requestqueue_mutex);
+
+ for (;;) {
+ if (list_empty(&ls->ls_requestqueue)) {
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+ error = 0;
+ break;
+ }
+ e = list_entry(ls->ls_requestqueue.next, struct rq_entry, list);
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+
+ ms = &e->request;
+
+ log_limit(ls, "dlm_process_requestqueue msg %d from %d "
+ "lkid %x remid %x result %d seq %u",
+ ms->m_type, ms->m_header.h_nodeid,
+ ms->m_lkid, ms->m_remid, ms->m_result,
+ e->recover_seq);
+
+ dlm_receive_message_saved(ls, &e->request, e->recover_seq);
+
+ mutex_lock(&ls->ls_requestqueue_mutex);
+ list_del(&e->list);
+ kfree(e);
+
+ if (dlm_locking_stopped(ls)) {
+ log_debug(ls, "process_requestqueue abort running");
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+ error = -EINTR;
+ break;
+ }
+ schedule();
+ }
+
+ return error;
+}
+
+/*
+ * After recovery is done, locking is resumed and dlm_recoverd takes all the
+ * saved requests and processes them as they would have been by dlm_recv. At
+ * the same time, dlm_recv will start receiving new requests from remote nodes.
+ * We want to delay dlm_recv processing new requests until dlm_recoverd has
+ * finished processing the old saved requests. We don't check for locking
+ * stopped here because dlm_ls_stop won't stop locking until it's suspended us
+ * (dlm_recv).
+ */
+
+void dlm_wait_requestqueue(struct dlm_ls *ls)
+{
+ for (;;) {
+ mutex_lock(&ls->ls_requestqueue_mutex);
+ if (list_empty(&ls->ls_requestqueue))
+ break;
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+ schedule();
+ }
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+}
+
+static int purge_request(struct dlm_ls *ls, struct dlm_message *ms, int nodeid)
+{
+ uint32_t type = ms->m_type;
+
+ /* the ls is being cleaned up and freed by release_lockspace */
+ if (!ls->ls_count)
+ return 1;
+
+ if (dlm_is_removed(ls, nodeid))
+ return 1;
+
+ /* directory operations are always purged because the directory is
+ always rebuilt during recovery and the lookups resent */
+
+ if (type == DLM_MSG_REMOVE ||
+ type == DLM_MSG_LOOKUP ||
+ type == DLM_MSG_LOOKUP_REPLY)
+ return 1;
+
+ if (!dlm_no_directory(ls))
+ return 0;
+
+ return 1;
+}
+
+void dlm_purge_requestqueue(struct dlm_ls *ls)
+{
+ struct dlm_message *ms;
+ struct rq_entry *e, *safe;
+
+ mutex_lock(&ls->ls_requestqueue_mutex);
+ list_for_each_entry_safe(e, safe, &ls->ls_requestqueue, list) {
+ ms = &e->request;
+
+ if (purge_request(ls, ms, e->nodeid)) {
+ list_del(&e->list);
+ kfree(e);
+ }
+ }
+ mutex_unlock(&ls->ls_requestqueue_mutex);
+}
+
Code Review / kvmfornfv.git / blobdiff