/*****************************************************************************************************************************************************************  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;	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->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;	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); 		dlm_receive_message_saved(ls, &e->request); 		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; 	/* with no directory, the master is likely to change as a part of	   recovery; requests to/from the defunct master need to be purged */ 	switch (type) {	case DLM_MSG_REQUEST:	case DLM_MSG_CONVERT:	case DLM_MSG_UNLOCK:	case DLM_MSG_CANCEL:		/* we're no longer the master of this resource, the sender		   will resend to the new master (see waiter_needs_recovery) */ 		if (dlm_hash2nodeid(ls, ms->m_hash) != dlm_our_nodeid())			return 1;		break; 	case DLM_MSG_REQUEST_REPLY:	case DLM_MSG_CONVERT_REPLY:	case DLM_MSG_UNLOCK_REPLY:	case DLM_MSG_CANCEL_REPLY:	case DLM_MSG_GRANT:		/* this reply is from the former master of the resource,		   we'll resend to the new master if needed */ 		if (dlm_hash2nodeid(ls, ms->m_hash) != nodeid)			return 1;		break;	} 	return 0;} 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);}