![Sunil Mushran](/assets/img/avatar_default.png)
In dlm_migrate_lockres(), we check upfront whether the lockres is a candidate for migration. This patch encapsulates that code in a separate function so that dlm_empty_lockres() can also use it during umount. This patch addresses the umount process spinning problem. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
3479 lines
95 KiB
C
3479 lines
95 KiB
C
/* -*- mode: c; c-basic-offset: 8; -*-
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* vim: noexpandtab sw=8 ts=8 sts=0:
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*
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* dlmmod.c
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*
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* standalone DLM module
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*
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* Copyright (C) 2004 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/types.h>
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#include <linux/slab.h>
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#include <linux/highmem.h>
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#include <linux/utsname.h>
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#include <linux/init.h>
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#include <linux/sysctl.h>
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#include <linux/random.h>
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#include <linux/blkdev.h>
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#include <linux/socket.h>
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#include <linux/inet.h>
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#include <linux/spinlock.h>
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#include <linux/delay.h>
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#include "cluster/heartbeat.h"
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#include "cluster/nodemanager.h"
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#include "cluster/tcp.h"
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#include "dlmapi.h"
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#include "dlmcommon.h"
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#include "dlmdomain.h"
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#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER)
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#include "cluster/masklog.h"
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enum dlm_mle_type {
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DLM_MLE_BLOCK,
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DLM_MLE_MASTER,
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DLM_MLE_MIGRATION
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};
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struct dlm_lock_name
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{
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u8 len;
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u8 name[DLM_LOCKID_NAME_MAX];
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};
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struct dlm_master_list_entry
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{
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struct list_head list;
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struct list_head hb_events;
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struct dlm_ctxt *dlm;
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spinlock_t spinlock;
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wait_queue_head_t wq;
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atomic_t woken;
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struct kref mle_refs;
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int inuse;
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unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
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unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
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unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
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unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
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u8 master;
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u8 new_master;
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enum dlm_mle_type type;
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struct o2hb_callback_func mle_hb_up;
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struct o2hb_callback_func mle_hb_down;
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union {
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struct dlm_lock_resource *res;
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struct dlm_lock_name name;
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} u;
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};
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static void dlm_mle_node_down(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle,
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struct o2nm_node *node,
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int idx);
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static void dlm_mle_node_up(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle,
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struct o2nm_node *node,
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int idx);
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static void dlm_assert_master_worker(struct dlm_work_item *item, void *data);
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static int dlm_do_assert_master(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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void *nodemap, u32 flags);
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static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data);
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static inline int dlm_mle_equal(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle,
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const char *name,
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unsigned int namelen)
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{
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struct dlm_lock_resource *res;
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if (dlm != mle->dlm)
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return 0;
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if (mle->type == DLM_MLE_BLOCK ||
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mle->type == DLM_MLE_MIGRATION) {
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if (namelen != mle->u.name.len ||
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memcmp(name, mle->u.name.name, namelen)!=0)
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return 0;
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} else {
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res = mle->u.res;
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if (namelen != res->lockname.len ||
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memcmp(res->lockname.name, name, namelen) != 0)
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return 0;
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}
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return 1;
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}
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#define dlm_print_nodemap(m) _dlm_print_nodemap(m,#m)
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static void _dlm_print_nodemap(unsigned long *map, const char *mapname)
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{
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int i;
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printk("%s=[ ", mapname);
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for (i=0; i<O2NM_MAX_NODES; i++)
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if (test_bit(i, map))
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printk("%d ", i);
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printk("]");
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}
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static void dlm_print_one_mle(struct dlm_master_list_entry *mle)
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{
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int refs;
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char *type;
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char attached;
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u8 master;
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unsigned int namelen;
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const char *name;
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struct kref *k;
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unsigned long *maybe = mle->maybe_map,
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*vote = mle->vote_map,
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*resp = mle->response_map,
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*node = mle->node_map;
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k = &mle->mle_refs;
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if (mle->type == DLM_MLE_BLOCK)
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type = "BLK";
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else if (mle->type == DLM_MLE_MASTER)
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type = "MAS";
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else
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type = "MIG";
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refs = atomic_read(&k->refcount);
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master = mle->master;
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attached = (list_empty(&mle->hb_events) ? 'N' : 'Y');
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if (mle->type != DLM_MLE_MASTER) {
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namelen = mle->u.name.len;
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name = mle->u.name.name;
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} else {
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namelen = mle->u.res->lockname.len;
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name = mle->u.res->lockname.name;
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}
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mlog(ML_NOTICE, "%.*s: %3s refs=%3d mas=%3u new=%3u evt=%c inuse=%d ",
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namelen, name, type, refs, master, mle->new_master, attached,
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mle->inuse);
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dlm_print_nodemap(maybe);
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printk(", ");
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dlm_print_nodemap(vote);
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printk(", ");
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dlm_print_nodemap(resp);
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printk(", ");
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dlm_print_nodemap(node);
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printk(", ");
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printk("\n");
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}
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#if 0
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/* Code here is included but defined out as it aids debugging */
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static void dlm_dump_mles(struct dlm_ctxt *dlm)
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{
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struct dlm_master_list_entry *mle;
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struct list_head *iter;
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mlog(ML_NOTICE, "dumping all mles for domain %s:\n", dlm->name);
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spin_lock(&dlm->master_lock);
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list_for_each(iter, &dlm->master_list) {
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mle = list_entry(iter, struct dlm_master_list_entry, list);
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dlm_print_one_mle(mle);
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}
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spin_unlock(&dlm->master_lock);
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}
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int dlm_dump_all_mles(const char __user *data, unsigned int len)
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{
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struct list_head *iter;
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struct dlm_ctxt *dlm;
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spin_lock(&dlm_domain_lock);
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list_for_each(iter, &dlm_domains) {
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dlm = list_entry (iter, struct dlm_ctxt, list);
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mlog(ML_NOTICE, "found dlm: %p, name=%s\n", dlm, dlm->name);
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dlm_dump_mles(dlm);
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}
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spin_unlock(&dlm_domain_lock);
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return len;
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}
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EXPORT_SYMBOL_GPL(dlm_dump_all_mles);
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#endif /* 0 */
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static struct kmem_cache *dlm_mle_cache = NULL;
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static void dlm_mle_release(struct kref *kref);
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static void dlm_init_mle(struct dlm_master_list_entry *mle,
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enum dlm_mle_type type,
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struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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const char *name,
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unsigned int namelen);
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static void dlm_put_mle(struct dlm_master_list_entry *mle);
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static void __dlm_put_mle(struct dlm_master_list_entry *mle);
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static int dlm_find_mle(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry **mle,
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char *name, unsigned int namelen);
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static int dlm_do_master_request(struct dlm_lock_resource *res,
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struct dlm_master_list_entry *mle, int to);
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static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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struct dlm_master_list_entry *mle,
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int *blocked);
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static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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struct dlm_master_list_entry *mle,
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int blocked);
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static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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struct dlm_master_list_entry *mle,
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struct dlm_master_list_entry **oldmle,
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const char *name, unsigned int namelen,
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u8 new_master, u8 master);
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static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res);
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static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res);
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static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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u8 target);
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static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res);
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int dlm_is_host_down(int errno)
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{
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switch (errno) {
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case -EBADF:
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case -ECONNREFUSED:
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case -ENOTCONN:
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case -ECONNRESET:
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case -EPIPE:
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case -EHOSTDOWN:
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case -EHOSTUNREACH:
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case -ETIMEDOUT:
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case -ECONNABORTED:
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case -ENETDOWN:
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case -ENETUNREACH:
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case -ENETRESET:
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case -ESHUTDOWN:
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case -ENOPROTOOPT:
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case -EINVAL: /* if returned from our tcp code,
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this means there is no socket */
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return 1;
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}
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return 0;
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}
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/*
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* MASTER LIST FUNCTIONS
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*/
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/*
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* regarding master list entries and heartbeat callbacks:
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*
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* in order to avoid sleeping and allocation that occurs in
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* heartbeat, master list entries are simply attached to the
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* dlm's established heartbeat callbacks. the mle is attached
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* when it is created, and since the dlm->spinlock is held at
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* that time, any heartbeat event will be properly discovered
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* by the mle. the mle needs to be detached from the
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* dlm->mle_hb_events list as soon as heartbeat events are no
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* longer useful to the mle, and before the mle is freed.
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*
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* as a general rule, heartbeat events are no longer needed by
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* the mle once an "answer" regarding the lock master has been
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* received.
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*/
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static inline void __dlm_mle_attach_hb_events(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle)
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{
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assert_spin_locked(&dlm->spinlock);
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list_add_tail(&mle->hb_events, &dlm->mle_hb_events);
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}
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static inline void __dlm_mle_detach_hb_events(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle)
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{
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if (!list_empty(&mle->hb_events))
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list_del_init(&mle->hb_events);
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}
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static inline void dlm_mle_detach_hb_events(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry *mle)
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{
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spin_lock(&dlm->spinlock);
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__dlm_mle_detach_hb_events(dlm, mle);
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spin_unlock(&dlm->spinlock);
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}
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static void dlm_get_mle_inuse(struct dlm_master_list_entry *mle)
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{
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struct dlm_ctxt *dlm;
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dlm = mle->dlm;
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assert_spin_locked(&dlm->spinlock);
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assert_spin_locked(&dlm->master_lock);
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mle->inuse++;
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kref_get(&mle->mle_refs);
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}
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static void dlm_put_mle_inuse(struct dlm_master_list_entry *mle)
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{
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struct dlm_ctxt *dlm;
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dlm = mle->dlm;
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spin_lock(&dlm->spinlock);
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spin_lock(&dlm->master_lock);
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mle->inuse--;
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__dlm_put_mle(mle);
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spin_unlock(&dlm->master_lock);
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spin_unlock(&dlm->spinlock);
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}
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/* remove from list and free */
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static void __dlm_put_mle(struct dlm_master_list_entry *mle)
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{
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struct dlm_ctxt *dlm;
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dlm = mle->dlm;
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assert_spin_locked(&dlm->spinlock);
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assert_spin_locked(&dlm->master_lock);
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if (!atomic_read(&mle->mle_refs.refcount)) {
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/* this may or may not crash, but who cares.
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* it's a BUG. */
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mlog(ML_ERROR, "bad mle: %p\n", mle);
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dlm_print_one_mle(mle);
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BUG();
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} else
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kref_put(&mle->mle_refs, dlm_mle_release);
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}
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/* must not have any spinlocks coming in */
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static void dlm_put_mle(struct dlm_master_list_entry *mle)
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{
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struct dlm_ctxt *dlm;
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dlm = mle->dlm;
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spin_lock(&dlm->spinlock);
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spin_lock(&dlm->master_lock);
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__dlm_put_mle(mle);
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spin_unlock(&dlm->master_lock);
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spin_unlock(&dlm->spinlock);
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}
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static inline void dlm_get_mle(struct dlm_master_list_entry *mle)
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{
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kref_get(&mle->mle_refs);
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}
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static void dlm_init_mle(struct dlm_master_list_entry *mle,
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enum dlm_mle_type type,
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struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res,
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const char *name,
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unsigned int namelen)
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{
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assert_spin_locked(&dlm->spinlock);
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mle->dlm = dlm;
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mle->type = type;
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INIT_LIST_HEAD(&mle->list);
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INIT_LIST_HEAD(&mle->hb_events);
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memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
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spin_lock_init(&mle->spinlock);
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init_waitqueue_head(&mle->wq);
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atomic_set(&mle->woken, 0);
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kref_init(&mle->mle_refs);
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memset(mle->response_map, 0, sizeof(mle->response_map));
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mle->master = O2NM_MAX_NODES;
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mle->new_master = O2NM_MAX_NODES;
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mle->inuse = 0;
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if (mle->type == DLM_MLE_MASTER) {
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BUG_ON(!res);
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mle->u.res = res;
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} else if (mle->type == DLM_MLE_BLOCK) {
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BUG_ON(!name);
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memcpy(mle->u.name.name, name, namelen);
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mle->u.name.len = namelen;
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} else /* DLM_MLE_MIGRATION */ {
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BUG_ON(!name);
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memcpy(mle->u.name.name, name, namelen);
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mle->u.name.len = namelen;
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}
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/* copy off the node_map and register hb callbacks on our copy */
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memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map));
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memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map));
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clear_bit(dlm->node_num, mle->vote_map);
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clear_bit(dlm->node_num, mle->node_map);
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/* attach the mle to the domain node up/down events */
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__dlm_mle_attach_hb_events(dlm, mle);
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}
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/* returns 1 if found, 0 if not */
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static int dlm_find_mle(struct dlm_ctxt *dlm,
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struct dlm_master_list_entry **mle,
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char *name, unsigned int namelen)
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{
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struct dlm_master_list_entry *tmpmle;
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struct list_head *iter;
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assert_spin_locked(&dlm->master_lock);
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list_for_each(iter, &dlm->master_list) {
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tmpmle = list_entry(iter, struct dlm_master_list_entry, list);
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if (!dlm_mle_equal(dlm, tmpmle, name, namelen))
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continue;
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dlm_get_mle(tmpmle);
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*mle = tmpmle;
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return 1;
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}
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return 0;
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}
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void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up)
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{
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struct dlm_master_list_entry *mle;
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struct list_head *iter;
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assert_spin_locked(&dlm->spinlock);
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list_for_each(iter, &dlm->mle_hb_events) {
|
|
mle = list_entry(iter, struct dlm_master_list_entry,
|
|
hb_events);
|
|
if (node_up)
|
|
dlm_mle_node_up(dlm, mle, NULL, idx);
|
|
else
|
|
dlm_mle_node_down(dlm, mle, NULL, idx);
|
|
}
|
|
}
|
|
|
|
static void dlm_mle_node_down(struct dlm_ctxt *dlm,
|
|
struct dlm_master_list_entry *mle,
|
|
struct o2nm_node *node, int idx)
|
|
{
|
|
spin_lock(&mle->spinlock);
|
|
|
|
if (!test_bit(idx, mle->node_map))
|
|
mlog(0, "node %u already removed from nodemap!\n", idx);
|
|
else
|
|
clear_bit(idx, mle->node_map);
|
|
|
|
spin_unlock(&mle->spinlock);
|
|
}
|
|
|
|
static void dlm_mle_node_up(struct dlm_ctxt *dlm,
|
|
struct dlm_master_list_entry *mle,
|
|
struct o2nm_node *node, int idx)
|
|
{
|
|
spin_lock(&mle->spinlock);
|
|
|
|
if (test_bit(idx, mle->node_map))
|
|
mlog(0, "node %u already in node map!\n", idx);
|
|
else
|
|
set_bit(idx, mle->node_map);
|
|
|
|
spin_unlock(&mle->spinlock);
|
|
}
|
|
|
|
|
|
int dlm_init_mle_cache(void)
|
|
{
|
|
dlm_mle_cache = kmem_cache_create("dlm_mle_cache",
|
|
sizeof(struct dlm_master_list_entry),
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
NULL, NULL);
|
|
if (dlm_mle_cache == NULL)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
void dlm_destroy_mle_cache(void)
|
|
{
|
|
if (dlm_mle_cache)
|
|
kmem_cache_destroy(dlm_mle_cache);
|
|
}
|
|
|
|
static void dlm_mle_release(struct kref *kref)
|
|
{
|
|
struct dlm_master_list_entry *mle;
|
|
struct dlm_ctxt *dlm;
|
|
|
|
mlog_entry_void();
|
|
|
|
mle = container_of(kref, struct dlm_master_list_entry, mle_refs);
|
|
dlm = mle->dlm;
|
|
|
|
if (mle->type != DLM_MLE_MASTER) {
|
|
mlog(0, "calling mle_release for %.*s, type %d\n",
|
|
mle->u.name.len, mle->u.name.name, mle->type);
|
|
} else {
|
|
mlog(0, "calling mle_release for %.*s, type %d\n",
|
|
mle->u.res->lockname.len,
|
|
mle->u.res->lockname.name, mle->type);
|
|
}
|
|
assert_spin_locked(&dlm->spinlock);
|
|
assert_spin_locked(&dlm->master_lock);
|
|
|
|
/* remove from list if not already */
|
|
if (!list_empty(&mle->list))
|
|
list_del_init(&mle->list);
|
|
|
|
/* detach the mle from the domain node up/down events */
|
|
__dlm_mle_detach_hb_events(dlm, mle);
|
|
|
|
/* NOTE: kfree under spinlock here.
|
|
* if this is bad, we can move this to a freelist. */
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
}
|
|
|
|
|
|
/*
|
|
* LOCK RESOURCE FUNCTIONS
|
|
*/
|
|
|
|
static void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
u8 owner)
|
|
{
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
mlog_entry("%.*s, %u\n", res->lockname.len, res->lockname.name, owner);
|
|
|
|
if (owner == dlm->node_num)
|
|
atomic_inc(&dlm->local_resources);
|
|
else if (owner == DLM_LOCK_RES_OWNER_UNKNOWN)
|
|
atomic_inc(&dlm->unknown_resources);
|
|
else
|
|
atomic_inc(&dlm->remote_resources);
|
|
|
|
res->owner = owner;
|
|
}
|
|
|
|
void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res, u8 owner)
|
|
{
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
if (owner == res->owner)
|
|
return;
|
|
|
|
if (res->owner == dlm->node_num)
|
|
atomic_dec(&dlm->local_resources);
|
|
else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN)
|
|
atomic_dec(&dlm->unknown_resources);
|
|
else
|
|
atomic_dec(&dlm->remote_resources);
|
|
|
|
dlm_set_lockres_owner(dlm, res, owner);
|
|
}
|
|
|
|
|
|
static void dlm_lockres_release(struct kref *kref)
|
|
{
|
|
struct dlm_lock_resource *res;
|
|
|
|
res = container_of(kref, struct dlm_lock_resource, refs);
|
|
|
|
/* This should not happen -- all lockres' have a name
|
|
* associated with them at init time. */
|
|
BUG_ON(!res->lockname.name);
|
|
|
|
mlog(0, "destroying lockres %.*s\n", res->lockname.len,
|
|
res->lockname.name);
|
|
|
|
if (!hlist_unhashed(&res->hash_node) ||
|
|
!list_empty(&res->granted) ||
|
|
!list_empty(&res->converting) ||
|
|
!list_empty(&res->blocked) ||
|
|
!list_empty(&res->dirty) ||
|
|
!list_empty(&res->recovering) ||
|
|
!list_empty(&res->purge)) {
|
|
mlog(ML_ERROR,
|
|
"Going to BUG for resource %.*s."
|
|
" We're on a list! [%c%c%c%c%c%c%c]\n",
|
|
res->lockname.len, res->lockname.name,
|
|
!hlist_unhashed(&res->hash_node) ? 'H' : ' ',
|
|
!list_empty(&res->granted) ? 'G' : ' ',
|
|
!list_empty(&res->converting) ? 'C' : ' ',
|
|
!list_empty(&res->blocked) ? 'B' : ' ',
|
|
!list_empty(&res->dirty) ? 'D' : ' ',
|
|
!list_empty(&res->recovering) ? 'R' : ' ',
|
|
!list_empty(&res->purge) ? 'P' : ' ');
|
|
|
|
dlm_print_one_lock_resource(res);
|
|
}
|
|
|
|
/* By the time we're ready to blow this guy away, we shouldn't
|
|
* be on any lists. */
|
|
BUG_ON(!hlist_unhashed(&res->hash_node));
|
|
BUG_ON(!list_empty(&res->granted));
|
|
BUG_ON(!list_empty(&res->converting));
|
|
BUG_ON(!list_empty(&res->blocked));
|
|
BUG_ON(!list_empty(&res->dirty));
|
|
BUG_ON(!list_empty(&res->recovering));
|
|
BUG_ON(!list_empty(&res->purge));
|
|
|
|
kfree(res->lockname.name);
|
|
|
|
kfree(res);
|
|
}
|
|
|
|
void dlm_lockres_put(struct dlm_lock_resource *res)
|
|
{
|
|
kref_put(&res->refs, dlm_lockres_release);
|
|
}
|
|
|
|
static void dlm_init_lockres(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
const char *name, unsigned int namelen)
|
|
{
|
|
char *qname;
|
|
|
|
/* If we memset here, we lose our reference to the kmalloc'd
|
|
* res->lockname.name, so be sure to init every field
|
|
* correctly! */
|
|
|
|
qname = (char *) res->lockname.name;
|
|
memcpy(qname, name, namelen);
|
|
|
|
res->lockname.len = namelen;
|
|
res->lockname.hash = dlm_lockid_hash(name, namelen);
|
|
|
|
init_waitqueue_head(&res->wq);
|
|
spin_lock_init(&res->spinlock);
|
|
INIT_HLIST_NODE(&res->hash_node);
|
|
INIT_LIST_HEAD(&res->granted);
|
|
INIT_LIST_HEAD(&res->converting);
|
|
INIT_LIST_HEAD(&res->blocked);
|
|
INIT_LIST_HEAD(&res->dirty);
|
|
INIT_LIST_HEAD(&res->recovering);
|
|
INIT_LIST_HEAD(&res->purge);
|
|
atomic_set(&res->asts_reserved, 0);
|
|
res->migration_pending = 0;
|
|
res->inflight_locks = 0;
|
|
|
|
kref_init(&res->refs);
|
|
|
|
/* just for consistency */
|
|
spin_lock(&res->spinlock);
|
|
dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
res->state = DLM_LOCK_RES_IN_PROGRESS;
|
|
|
|
res->last_used = 0;
|
|
|
|
memset(res->lvb, 0, DLM_LVB_LEN);
|
|
memset(res->refmap, 0, sizeof(res->refmap));
|
|
}
|
|
|
|
struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
|
|
const char *name,
|
|
unsigned int namelen)
|
|
{
|
|
struct dlm_lock_resource *res;
|
|
|
|
res = kmalloc(sizeof(struct dlm_lock_resource), GFP_NOFS);
|
|
if (!res)
|
|
return NULL;
|
|
|
|
res->lockname.name = kmalloc(namelen, GFP_NOFS);
|
|
if (!res->lockname.name) {
|
|
kfree(res);
|
|
return NULL;
|
|
}
|
|
|
|
dlm_init_lockres(dlm, res, name, namelen);
|
|
return res;
|
|
}
|
|
|
|
void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
int new_lockres,
|
|
const char *file,
|
|
int line)
|
|
{
|
|
if (!new_lockres)
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
if (!test_bit(dlm->node_num, res->refmap)) {
|
|
BUG_ON(res->inflight_locks != 0);
|
|
dlm_lockres_set_refmap_bit(dlm->node_num, res);
|
|
}
|
|
res->inflight_locks++;
|
|
mlog(0, "%s:%.*s: inflight++: now %u\n",
|
|
dlm->name, res->lockname.len, res->lockname.name,
|
|
res->inflight_locks);
|
|
}
|
|
|
|
void __dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
const char *file,
|
|
int line)
|
|
{
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
BUG_ON(res->inflight_locks == 0);
|
|
res->inflight_locks--;
|
|
mlog(0, "%s:%.*s: inflight--: now %u\n",
|
|
dlm->name, res->lockname.len, res->lockname.name,
|
|
res->inflight_locks);
|
|
if (res->inflight_locks == 0)
|
|
dlm_lockres_clear_refmap_bit(dlm->node_num, res);
|
|
wake_up(&res->wq);
|
|
}
|
|
|
|
/*
|
|
* lookup a lock resource by name.
|
|
* may already exist in the hashtable.
|
|
* lockid is null terminated
|
|
*
|
|
* if not, allocate enough for the lockres and for
|
|
* the temporary structure used in doing the mastering.
|
|
*
|
|
* also, do a lookup in the dlm->master_list to see
|
|
* if another node has begun mastering the same lock.
|
|
* if so, there should be a block entry in there
|
|
* for this name, and we should *not* attempt to master
|
|
* the lock here. need to wait around for that node
|
|
* to assert_master (or die).
|
|
*
|
|
*/
|
|
struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
|
|
const char *lockid,
|
|
int namelen,
|
|
int flags)
|
|
{
|
|
struct dlm_lock_resource *tmpres=NULL, *res=NULL;
|
|
struct dlm_master_list_entry *mle = NULL;
|
|
struct dlm_master_list_entry *alloc_mle = NULL;
|
|
int blocked = 0;
|
|
int ret, nodenum;
|
|
struct dlm_node_iter iter;
|
|
unsigned int hash;
|
|
int tries = 0;
|
|
int bit, wait_on_recovery = 0;
|
|
int drop_inflight_if_nonlocal = 0;
|
|
|
|
BUG_ON(!lockid);
|
|
|
|
hash = dlm_lockid_hash(lockid, namelen);
|
|
|
|
mlog(0, "get lockres %s (len %d)\n", lockid, namelen);
|
|
|
|
lookup:
|
|
spin_lock(&dlm->spinlock);
|
|
tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash);
|
|
if (tmpres) {
|
|
int dropping_ref = 0;
|
|
|
|
spin_lock(&tmpres->spinlock);
|
|
if (tmpres->owner == dlm->node_num) {
|
|
BUG_ON(tmpres->state & DLM_LOCK_RES_DROPPING_REF);
|
|
dlm_lockres_grab_inflight_ref(dlm, tmpres);
|
|
} else if (tmpres->state & DLM_LOCK_RES_DROPPING_REF)
|
|
dropping_ref = 1;
|
|
spin_unlock(&tmpres->spinlock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/* wait until done messaging the master, drop our ref to allow
|
|
* the lockres to be purged, start over. */
|
|
if (dropping_ref) {
|
|
spin_lock(&tmpres->spinlock);
|
|
__dlm_wait_on_lockres_flags(tmpres, DLM_LOCK_RES_DROPPING_REF);
|
|
spin_unlock(&tmpres->spinlock);
|
|
dlm_lockres_put(tmpres);
|
|
tmpres = NULL;
|
|
goto lookup;
|
|
}
|
|
|
|
mlog(0, "found in hash!\n");
|
|
if (res)
|
|
dlm_lockres_put(res);
|
|
res = tmpres;
|
|
goto leave;
|
|
}
|
|
|
|
if (!res) {
|
|
spin_unlock(&dlm->spinlock);
|
|
mlog(0, "allocating a new resource\n");
|
|
/* nothing found and we need to allocate one. */
|
|
alloc_mle = (struct dlm_master_list_entry *)
|
|
kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
|
|
if (!alloc_mle)
|
|
goto leave;
|
|
res = dlm_new_lockres(dlm, lockid, namelen);
|
|
if (!res)
|
|
goto leave;
|
|
goto lookup;
|
|
}
|
|
|
|
mlog(0, "no lockres found, allocated our own: %p\n", res);
|
|
|
|
if (flags & LKM_LOCAL) {
|
|
/* caller knows it's safe to assume it's not mastered elsewhere
|
|
* DONE! return right away */
|
|
spin_lock(&res->spinlock);
|
|
dlm_change_lockres_owner(dlm, res, dlm->node_num);
|
|
__dlm_insert_lockres(dlm, res);
|
|
dlm_lockres_grab_inflight_ref(dlm, res);
|
|
spin_unlock(&res->spinlock);
|
|
spin_unlock(&dlm->spinlock);
|
|
/* lockres still marked IN_PROGRESS */
|
|
goto wake_waiters;
|
|
}
|
|
|
|
/* check master list to see if another node has started mastering it */
|
|
spin_lock(&dlm->master_lock);
|
|
|
|
/* if we found a block, wait for lock to be mastered by another node */
|
|
blocked = dlm_find_mle(dlm, &mle, (char *)lockid, namelen);
|
|
if (blocked) {
|
|
int mig;
|
|
if (mle->type == DLM_MLE_MASTER) {
|
|
mlog(ML_ERROR, "master entry for nonexistent lock!\n");
|
|
BUG();
|
|
}
|
|
mig = (mle->type == DLM_MLE_MIGRATION);
|
|
/* if there is a migration in progress, let the migration
|
|
* finish before continuing. we can wait for the absence
|
|
* of the MIGRATION mle: either the migrate finished or
|
|
* one of the nodes died and the mle was cleaned up.
|
|
* if there is a BLOCK here, but it already has a master
|
|
* set, we are too late. the master does not have a ref
|
|
* for us in the refmap. detach the mle and drop it.
|
|
* either way, go back to the top and start over. */
|
|
if (mig || mle->master != O2NM_MAX_NODES) {
|
|
BUG_ON(mig && mle->master == dlm->node_num);
|
|
/* we arrived too late. the master does not
|
|
* have a ref for us. retry. */
|
|
mlog(0, "%s:%.*s: late on %s\n",
|
|
dlm->name, namelen, lockid,
|
|
mig ? "MIGRATION" : "BLOCK");
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/* master is known, detach */
|
|
if (!mig)
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle(mle);
|
|
mle = NULL;
|
|
/* this is lame, but we cant wait on either
|
|
* the mle or lockres waitqueue here */
|
|
if (mig)
|
|
msleep(100);
|
|
goto lookup;
|
|
}
|
|
} else {
|
|
/* go ahead and try to master lock on this node */
|
|
mle = alloc_mle;
|
|
/* make sure this does not get freed below */
|
|
alloc_mle = NULL;
|
|
dlm_init_mle(mle, DLM_MLE_MASTER, dlm, res, NULL, 0);
|
|
set_bit(dlm->node_num, mle->maybe_map);
|
|
list_add(&mle->list, &dlm->master_list);
|
|
|
|
/* still holding the dlm spinlock, check the recovery map
|
|
* to see if there are any nodes that still need to be
|
|
* considered. these will not appear in the mle nodemap
|
|
* but they might own this lockres. wait on them. */
|
|
bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
|
|
if (bit < O2NM_MAX_NODES) {
|
|
mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to"
|
|
"recover before lock mastery can begin\n",
|
|
dlm->name, namelen, (char *)lockid, bit);
|
|
wait_on_recovery = 1;
|
|
}
|
|
}
|
|
|
|
/* at this point there is either a DLM_MLE_BLOCK or a
|
|
* DLM_MLE_MASTER on the master list, so it's safe to add the
|
|
* lockres to the hashtable. anyone who finds the lock will
|
|
* still have to wait on the IN_PROGRESS. */
|
|
|
|
/* finally add the lockres to its hash bucket */
|
|
__dlm_insert_lockres(dlm, res);
|
|
/* since this lockres is new it doesnt not require the spinlock */
|
|
dlm_lockres_grab_inflight_ref_new(dlm, res);
|
|
|
|
/* if this node does not become the master make sure to drop
|
|
* this inflight reference below */
|
|
drop_inflight_if_nonlocal = 1;
|
|
|
|
/* get an extra ref on the mle in case this is a BLOCK
|
|
* if so, the creator of the BLOCK may try to put the last
|
|
* ref at this time in the assert master handler, so we
|
|
* need an extra one to keep from a bad ptr deref. */
|
|
dlm_get_mle_inuse(mle);
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
redo_request:
|
|
while (wait_on_recovery) {
|
|
/* any cluster changes that occurred after dropping the
|
|
* dlm spinlock would be detectable be a change on the mle,
|
|
* so we only need to clear out the recovery map once. */
|
|
if (dlm_is_recovery_lock(lockid, namelen)) {
|
|
mlog(ML_NOTICE, "%s: recovery map is not empty, but "
|
|
"must master $RECOVERY lock now\n", dlm->name);
|
|
if (!dlm_pre_master_reco_lockres(dlm, res))
|
|
wait_on_recovery = 0;
|
|
else {
|
|
mlog(0, "%s: waiting 500ms for heartbeat state "
|
|
"change\n", dlm->name);
|
|
msleep(500);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
dlm_kick_recovery_thread(dlm);
|
|
msleep(1000);
|
|
dlm_wait_for_recovery(dlm);
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
|
|
if (bit < O2NM_MAX_NODES) {
|
|
mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to"
|
|
"recover before lock mastery can begin\n",
|
|
dlm->name, namelen, (char *)lockid, bit);
|
|
wait_on_recovery = 1;
|
|
} else
|
|
wait_on_recovery = 0;
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
if (wait_on_recovery)
|
|
dlm_wait_for_node_recovery(dlm, bit, 10000);
|
|
}
|
|
|
|
/* must wait for lock to be mastered elsewhere */
|
|
if (blocked)
|
|
goto wait;
|
|
|
|
ret = -EINVAL;
|
|
dlm_node_iter_init(mle->vote_map, &iter);
|
|
while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
|
|
ret = dlm_do_master_request(res, mle, nodenum);
|
|
if (ret < 0)
|
|
mlog_errno(ret);
|
|
if (mle->master != O2NM_MAX_NODES) {
|
|
/* found a master ! */
|
|
if (mle->master <= nodenum)
|
|
break;
|
|
/* if our master request has not reached the master
|
|
* yet, keep going until it does. this is how the
|
|
* master will know that asserts are needed back to
|
|
* the lower nodes. */
|
|
mlog(0, "%s:%.*s: requests only up to %u but master "
|
|
"is %u, keep going\n", dlm->name, namelen,
|
|
lockid, nodenum, mle->master);
|
|
}
|
|
}
|
|
|
|
wait:
|
|
/* keep going until the response map includes all nodes */
|
|
ret = dlm_wait_for_lock_mastery(dlm, res, mle, &blocked);
|
|
if (ret < 0) {
|
|
wait_on_recovery = 1;
|
|
mlog(0, "%s:%.*s: node map changed, redo the "
|
|
"master request now, blocked=%d\n",
|
|
dlm->name, res->lockname.len,
|
|
res->lockname.name, blocked);
|
|
if (++tries > 20) {
|
|
mlog(ML_ERROR, "%s:%.*s: spinning on "
|
|
"dlm_wait_for_lock_mastery, blocked=%d\n",
|
|
dlm->name, res->lockname.len,
|
|
res->lockname.name, blocked);
|
|
dlm_print_one_lock_resource(res);
|
|
dlm_print_one_mle(mle);
|
|
tries = 0;
|
|
}
|
|
goto redo_request;
|
|
}
|
|
|
|
mlog(0, "lockres mastered by %u\n", res->owner);
|
|
/* make sure we never continue without this */
|
|
BUG_ON(res->owner == O2NM_MAX_NODES);
|
|
|
|
/* master is known, detach if not already detached */
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle(mle);
|
|
/* put the extra ref */
|
|
dlm_put_mle_inuse(mle);
|
|
|
|
wake_waiters:
|
|
spin_lock(&res->spinlock);
|
|
if (res->owner != dlm->node_num && drop_inflight_if_nonlocal)
|
|
dlm_lockres_drop_inflight_ref(dlm, res);
|
|
res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
|
|
spin_unlock(&res->spinlock);
|
|
wake_up(&res->wq);
|
|
|
|
leave:
|
|
/* need to free the unused mle */
|
|
if (alloc_mle)
|
|
kmem_cache_free(dlm_mle_cache, alloc_mle);
|
|
|
|
return res;
|
|
}
|
|
|
|
|
|
#define DLM_MASTERY_TIMEOUT_MS 5000
|
|
|
|
static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
struct dlm_master_list_entry *mle,
|
|
int *blocked)
|
|
{
|
|
u8 m;
|
|
int ret, bit;
|
|
int map_changed, voting_done;
|
|
int assert, sleep;
|
|
|
|
recheck:
|
|
ret = 0;
|
|
assert = 0;
|
|
|
|
/* check if another node has already become the owner */
|
|
spin_lock(&res->spinlock);
|
|
if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
mlog(0, "%s:%.*s: owner is suddenly %u\n", dlm->name,
|
|
res->lockname.len, res->lockname.name, res->owner);
|
|
spin_unlock(&res->spinlock);
|
|
/* this will cause the master to re-assert across
|
|
* the whole cluster, freeing up mles */
|
|
if (res->owner != dlm->node_num) {
|
|
ret = dlm_do_master_request(res, mle, res->owner);
|
|
if (ret < 0) {
|
|
/* give recovery a chance to run */
|
|
mlog(ML_ERROR, "link to %u went down?: %d\n", res->owner, ret);
|
|
msleep(500);
|
|
goto recheck;
|
|
}
|
|
}
|
|
ret = 0;
|
|
goto leave;
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
|
|
spin_lock(&mle->spinlock);
|
|
m = mle->master;
|
|
map_changed = (memcmp(mle->vote_map, mle->node_map,
|
|
sizeof(mle->vote_map)) != 0);
|
|
voting_done = (memcmp(mle->vote_map, mle->response_map,
|
|
sizeof(mle->vote_map)) == 0);
|
|
|
|
/* restart if we hit any errors */
|
|
if (map_changed) {
|
|
int b;
|
|
mlog(0, "%s: %.*s: node map changed, restarting\n",
|
|
dlm->name, res->lockname.len, res->lockname.name);
|
|
ret = dlm_restart_lock_mastery(dlm, res, mle, *blocked);
|
|
b = (mle->type == DLM_MLE_BLOCK);
|
|
if ((*blocked && !b) || (!*blocked && b)) {
|
|
mlog(0, "%s:%.*s: status change: old=%d new=%d\n",
|
|
dlm->name, res->lockname.len, res->lockname.name,
|
|
*blocked, b);
|
|
*blocked = b;
|
|
}
|
|
spin_unlock(&mle->spinlock);
|
|
if (ret < 0) {
|
|
mlog_errno(ret);
|
|
goto leave;
|
|
}
|
|
mlog(0, "%s:%.*s: restart lock mastery succeeded, "
|
|
"rechecking now\n", dlm->name, res->lockname.len,
|
|
res->lockname.name);
|
|
goto recheck;
|
|
} else {
|
|
if (!voting_done) {
|
|
mlog(0, "map not changed and voting not done "
|
|
"for %s:%.*s\n", dlm->name, res->lockname.len,
|
|
res->lockname.name);
|
|
}
|
|
}
|
|
|
|
if (m != O2NM_MAX_NODES) {
|
|
/* another node has done an assert!
|
|
* all done! */
|
|
sleep = 0;
|
|
} else {
|
|
sleep = 1;
|
|
/* have all nodes responded? */
|
|
if (voting_done && !*blocked) {
|
|
bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
|
|
if (dlm->node_num <= bit) {
|
|
/* my node number is lowest.
|
|
* now tell other nodes that I am
|
|
* mastering this. */
|
|
mle->master = dlm->node_num;
|
|
/* ref was grabbed in get_lock_resource
|
|
* will be dropped in dlmlock_master */
|
|
assert = 1;
|
|
sleep = 0;
|
|
}
|
|
/* if voting is done, but we have not received
|
|
* an assert master yet, we must sleep */
|
|
}
|
|
}
|
|
|
|
spin_unlock(&mle->spinlock);
|
|
|
|
/* sleep if we haven't finished voting yet */
|
|
if (sleep) {
|
|
unsigned long timeo = msecs_to_jiffies(DLM_MASTERY_TIMEOUT_MS);
|
|
|
|
/*
|
|
if (atomic_read(&mle->mle_refs.refcount) < 2)
|
|
mlog(ML_ERROR, "mle (%p) refs=%d, name=%.*s\n", mle,
|
|
atomic_read(&mle->mle_refs.refcount),
|
|
res->lockname.len, res->lockname.name);
|
|
*/
|
|
atomic_set(&mle->woken, 0);
|
|
(void)wait_event_timeout(mle->wq,
|
|
(atomic_read(&mle->woken) == 1),
|
|
timeo);
|
|
if (res->owner == O2NM_MAX_NODES) {
|
|
mlog(0, "%s:%.*s: waiting again\n", dlm->name,
|
|
res->lockname.len, res->lockname.name);
|
|
goto recheck;
|
|
}
|
|
mlog(0, "done waiting, master is %u\n", res->owner);
|
|
ret = 0;
|
|
goto leave;
|
|
}
|
|
|
|
ret = 0; /* done */
|
|
if (assert) {
|
|
m = dlm->node_num;
|
|
mlog(0, "about to master %.*s here, this=%u\n",
|
|
res->lockname.len, res->lockname.name, m);
|
|
ret = dlm_do_assert_master(dlm, res, mle->vote_map, 0);
|
|
if (ret) {
|
|
/* This is a failure in the network path,
|
|
* not in the response to the assert_master
|
|
* (any nonzero response is a BUG on this node).
|
|
* Most likely a socket just got disconnected
|
|
* due to node death. */
|
|
mlog_errno(ret);
|
|
}
|
|
/* no longer need to restart lock mastery.
|
|
* all living nodes have been contacted. */
|
|
ret = 0;
|
|
}
|
|
|
|
/* set the lockres owner */
|
|
spin_lock(&res->spinlock);
|
|
/* mastery reference obtained either during
|
|
* assert_master_handler or in get_lock_resource */
|
|
dlm_change_lockres_owner(dlm, res, m);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
leave:
|
|
return ret;
|
|
}
|
|
|
|
struct dlm_bitmap_diff_iter
|
|
{
|
|
int curnode;
|
|
unsigned long *orig_bm;
|
|
unsigned long *cur_bm;
|
|
unsigned long diff_bm[BITS_TO_LONGS(O2NM_MAX_NODES)];
|
|
};
|
|
|
|
enum dlm_node_state_change
|
|
{
|
|
NODE_DOWN = -1,
|
|
NODE_NO_CHANGE = 0,
|
|
NODE_UP
|
|
};
|
|
|
|
static void dlm_bitmap_diff_iter_init(struct dlm_bitmap_diff_iter *iter,
|
|
unsigned long *orig_bm,
|
|
unsigned long *cur_bm)
|
|
{
|
|
unsigned long p1, p2;
|
|
int i;
|
|
|
|
iter->curnode = -1;
|
|
iter->orig_bm = orig_bm;
|
|
iter->cur_bm = cur_bm;
|
|
|
|
for (i = 0; i < BITS_TO_LONGS(O2NM_MAX_NODES); i++) {
|
|
p1 = *(iter->orig_bm + i);
|
|
p2 = *(iter->cur_bm + i);
|
|
iter->diff_bm[i] = (p1 & ~p2) | (p2 & ~p1);
|
|
}
|
|
}
|
|
|
|
static int dlm_bitmap_diff_iter_next(struct dlm_bitmap_diff_iter *iter,
|
|
enum dlm_node_state_change *state)
|
|
{
|
|
int bit;
|
|
|
|
if (iter->curnode >= O2NM_MAX_NODES)
|
|
return -ENOENT;
|
|
|
|
bit = find_next_bit(iter->diff_bm, O2NM_MAX_NODES,
|
|
iter->curnode+1);
|
|
if (bit >= O2NM_MAX_NODES) {
|
|
iter->curnode = O2NM_MAX_NODES;
|
|
return -ENOENT;
|
|
}
|
|
|
|
/* if it was there in the original then this node died */
|
|
if (test_bit(bit, iter->orig_bm))
|
|
*state = NODE_DOWN;
|
|
else
|
|
*state = NODE_UP;
|
|
|
|
iter->curnode = bit;
|
|
return bit;
|
|
}
|
|
|
|
|
|
static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
struct dlm_master_list_entry *mle,
|
|
int blocked)
|
|
{
|
|
struct dlm_bitmap_diff_iter bdi;
|
|
enum dlm_node_state_change sc;
|
|
int node;
|
|
int ret = 0;
|
|
|
|
mlog(0, "something happened such that the "
|
|
"master process may need to be restarted!\n");
|
|
|
|
assert_spin_locked(&mle->spinlock);
|
|
|
|
dlm_bitmap_diff_iter_init(&bdi, mle->vote_map, mle->node_map);
|
|
node = dlm_bitmap_diff_iter_next(&bdi, &sc);
|
|
while (node >= 0) {
|
|
if (sc == NODE_UP) {
|
|
/* a node came up. clear any old vote from
|
|
* the response map and set it in the vote map
|
|
* then restart the mastery. */
|
|
mlog(ML_NOTICE, "node %d up while restarting\n", node);
|
|
|
|
/* redo the master request, but only for the new node */
|
|
mlog(0, "sending request to new node\n");
|
|
clear_bit(node, mle->response_map);
|
|
set_bit(node, mle->vote_map);
|
|
} else {
|
|
mlog(ML_ERROR, "node down! %d\n", node);
|
|
if (blocked) {
|
|
int lowest = find_next_bit(mle->maybe_map,
|
|
O2NM_MAX_NODES, 0);
|
|
|
|
/* act like it was never there */
|
|
clear_bit(node, mle->maybe_map);
|
|
|
|
if (node == lowest) {
|
|
mlog(0, "expected master %u died"
|
|
" while this node was blocked "
|
|
"waiting on it!\n", node);
|
|
lowest = find_next_bit(mle->maybe_map,
|
|
O2NM_MAX_NODES,
|
|
lowest+1);
|
|
if (lowest < O2NM_MAX_NODES) {
|
|
mlog(0, "%s:%.*s:still "
|
|
"blocked. waiting on %u "
|
|
"now\n", dlm->name,
|
|
res->lockname.len,
|
|
res->lockname.name,
|
|
lowest);
|
|
} else {
|
|
/* mle is an MLE_BLOCK, but
|
|
* there is now nothing left to
|
|
* block on. we need to return
|
|
* all the way back out and try
|
|
* again with an MLE_MASTER.
|
|
* dlm_do_local_recovery_cleanup
|
|
* has already run, so the mle
|
|
* refcount is ok */
|
|
mlog(0, "%s:%.*s: no "
|
|
"longer blocking. try to "
|
|
"master this here\n",
|
|
dlm->name,
|
|
res->lockname.len,
|
|
res->lockname.name);
|
|
mle->type = DLM_MLE_MASTER;
|
|
mle->u.res = res;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* now blank out everything, as if we had never
|
|
* contacted anyone */
|
|
memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
|
|
memset(mle->response_map, 0, sizeof(mle->response_map));
|
|
/* reset the vote_map to the current node_map */
|
|
memcpy(mle->vote_map, mle->node_map,
|
|
sizeof(mle->node_map));
|
|
/* put myself into the maybe map */
|
|
if (mle->type != DLM_MLE_BLOCK)
|
|
set_bit(dlm->node_num, mle->maybe_map);
|
|
}
|
|
ret = -EAGAIN;
|
|
node = dlm_bitmap_diff_iter_next(&bdi, &sc);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* DLM_MASTER_REQUEST_MSG
|
|
*
|
|
* returns: 0 on success,
|
|
* -errno on a network error
|
|
*
|
|
* on error, the caller should assume the target node is "dead"
|
|
*
|
|
*/
|
|
|
|
static int dlm_do_master_request(struct dlm_lock_resource *res,
|
|
struct dlm_master_list_entry *mle, int to)
|
|
{
|
|
struct dlm_ctxt *dlm = mle->dlm;
|
|
struct dlm_master_request request;
|
|
int ret, response=0, resend;
|
|
|
|
memset(&request, 0, sizeof(request));
|
|
request.node_idx = dlm->node_num;
|
|
|
|
BUG_ON(mle->type == DLM_MLE_MIGRATION);
|
|
|
|
if (mle->type != DLM_MLE_MASTER) {
|
|
request.namelen = mle->u.name.len;
|
|
memcpy(request.name, mle->u.name.name, request.namelen);
|
|
} else {
|
|
request.namelen = mle->u.res->lockname.len;
|
|
memcpy(request.name, mle->u.res->lockname.name,
|
|
request.namelen);
|
|
}
|
|
|
|
again:
|
|
ret = o2net_send_message(DLM_MASTER_REQUEST_MSG, dlm->key, &request,
|
|
sizeof(request), to, &response);
|
|
if (ret < 0) {
|
|
if (ret == -ESRCH) {
|
|
/* should never happen */
|
|
mlog(ML_ERROR, "TCP stack not ready!\n");
|
|
BUG();
|
|
} else if (ret == -EINVAL) {
|
|
mlog(ML_ERROR, "bad args passed to o2net!\n");
|
|
BUG();
|
|
} else if (ret == -ENOMEM) {
|
|
mlog(ML_ERROR, "out of memory while trying to send "
|
|
"network message! retrying\n");
|
|
/* this is totally crude */
|
|
msleep(50);
|
|
goto again;
|
|
} else if (!dlm_is_host_down(ret)) {
|
|
/* not a network error. bad. */
|
|
mlog_errno(ret);
|
|
mlog(ML_ERROR, "unhandled error!");
|
|
BUG();
|
|
}
|
|
/* all other errors should be network errors,
|
|
* and likely indicate node death */
|
|
mlog(ML_ERROR, "link to %d went down!\n", to);
|
|
goto out;
|
|
}
|
|
|
|
ret = 0;
|
|
resend = 0;
|
|
spin_lock(&mle->spinlock);
|
|
switch (response) {
|
|
case DLM_MASTER_RESP_YES:
|
|
set_bit(to, mle->response_map);
|
|
mlog(0, "node %u is the master, response=YES\n", to);
|
|
mlog(0, "%s:%.*s: master node %u now knows I have a "
|
|
"reference\n", dlm->name, res->lockname.len,
|
|
res->lockname.name, to);
|
|
mle->master = to;
|
|
break;
|
|
case DLM_MASTER_RESP_NO:
|
|
mlog(0, "node %u not master, response=NO\n", to);
|
|
set_bit(to, mle->response_map);
|
|
break;
|
|
case DLM_MASTER_RESP_MAYBE:
|
|
mlog(0, "node %u not master, response=MAYBE\n", to);
|
|
set_bit(to, mle->response_map);
|
|
set_bit(to, mle->maybe_map);
|
|
break;
|
|
case DLM_MASTER_RESP_ERROR:
|
|
mlog(0, "node %u hit an error, resending\n", to);
|
|
resend = 1;
|
|
response = 0;
|
|
break;
|
|
default:
|
|
mlog(ML_ERROR, "bad response! %u\n", response);
|
|
BUG();
|
|
}
|
|
spin_unlock(&mle->spinlock);
|
|
if (resend) {
|
|
/* this is also totally crude */
|
|
msleep(50);
|
|
goto again;
|
|
}
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* locks that can be taken here:
|
|
* dlm->spinlock
|
|
* res->spinlock
|
|
* mle->spinlock
|
|
* dlm->master_list
|
|
*
|
|
* if possible, TRIM THIS DOWN!!!
|
|
*/
|
|
int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
|
|
void **ret_data)
|
|
{
|
|
u8 response = DLM_MASTER_RESP_MAYBE;
|
|
struct dlm_ctxt *dlm = data;
|
|
struct dlm_lock_resource *res = NULL;
|
|
struct dlm_master_request *request = (struct dlm_master_request *) msg->buf;
|
|
struct dlm_master_list_entry *mle = NULL, *tmpmle = NULL;
|
|
char *name;
|
|
unsigned int namelen, hash;
|
|
int found, ret;
|
|
int set_maybe;
|
|
int dispatch_assert = 0;
|
|
|
|
if (!dlm_grab(dlm))
|
|
return DLM_MASTER_RESP_NO;
|
|
|
|
if (!dlm_domain_fully_joined(dlm)) {
|
|
response = DLM_MASTER_RESP_NO;
|
|
goto send_response;
|
|
}
|
|
|
|
name = request->name;
|
|
namelen = request->namelen;
|
|
hash = dlm_lockid_hash(name, namelen);
|
|
|
|
if (namelen > DLM_LOCKID_NAME_MAX) {
|
|
response = DLM_IVBUFLEN;
|
|
goto send_response;
|
|
}
|
|
|
|
way_up_top:
|
|
spin_lock(&dlm->spinlock);
|
|
res = __dlm_lookup_lockres(dlm, name, namelen, hash);
|
|
if (res) {
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/* take care of the easy cases up front */
|
|
spin_lock(&res->spinlock);
|
|
if (res->state & (DLM_LOCK_RES_RECOVERING|
|
|
DLM_LOCK_RES_MIGRATING)) {
|
|
spin_unlock(&res->spinlock);
|
|
mlog(0, "returning DLM_MASTER_RESP_ERROR since res is "
|
|
"being recovered/migrated\n");
|
|
response = DLM_MASTER_RESP_ERROR;
|
|
if (mle)
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
goto send_response;
|
|
}
|
|
|
|
if (res->owner == dlm->node_num) {
|
|
mlog(0, "%s:%.*s: setting bit %u in refmap\n",
|
|
dlm->name, namelen, name, request->node_idx);
|
|
dlm_lockres_set_refmap_bit(request->node_idx, res);
|
|
spin_unlock(&res->spinlock);
|
|
response = DLM_MASTER_RESP_YES;
|
|
if (mle)
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
|
|
/* this node is the owner.
|
|
* there is some extra work that needs to
|
|
* happen now. the requesting node has
|
|
* caused all nodes up to this one to
|
|
* create mles. this node now needs to
|
|
* go back and clean those up. */
|
|
dispatch_assert = 1;
|
|
goto send_response;
|
|
} else if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
spin_unlock(&res->spinlock);
|
|
// mlog(0, "node %u is the master\n", res->owner);
|
|
response = DLM_MASTER_RESP_NO;
|
|
if (mle)
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
goto send_response;
|
|
}
|
|
|
|
/* ok, there is no owner. either this node is
|
|
* being blocked, or it is actively trying to
|
|
* master this lock. */
|
|
if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) {
|
|
mlog(ML_ERROR, "lock with no owner should be "
|
|
"in-progress!\n");
|
|
BUG();
|
|
}
|
|
|
|
// mlog(0, "lockres is in progress...\n");
|
|
spin_lock(&dlm->master_lock);
|
|
found = dlm_find_mle(dlm, &tmpmle, name, namelen);
|
|
if (!found) {
|
|
mlog(ML_ERROR, "no mle found for this lock!\n");
|
|
BUG();
|
|
}
|
|
set_maybe = 1;
|
|
spin_lock(&tmpmle->spinlock);
|
|
if (tmpmle->type == DLM_MLE_BLOCK) {
|
|
// mlog(0, "this node is waiting for "
|
|
// "lockres to be mastered\n");
|
|
response = DLM_MASTER_RESP_NO;
|
|
} else if (tmpmle->type == DLM_MLE_MIGRATION) {
|
|
mlog(0, "node %u is master, but trying to migrate to "
|
|
"node %u.\n", tmpmle->master, tmpmle->new_master);
|
|
if (tmpmle->master == dlm->node_num) {
|
|
mlog(ML_ERROR, "no owner on lockres, but this "
|
|
"node is trying to migrate it to %u?!\n",
|
|
tmpmle->new_master);
|
|
BUG();
|
|
} else {
|
|
/* the real master can respond on its own */
|
|
response = DLM_MASTER_RESP_NO;
|
|
}
|
|
} else if (tmpmle->master != DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
set_maybe = 0;
|
|
if (tmpmle->master == dlm->node_num) {
|
|
response = DLM_MASTER_RESP_YES;
|
|
/* this node will be the owner.
|
|
* go back and clean the mles on any
|
|
* other nodes */
|
|
dispatch_assert = 1;
|
|
dlm_lockres_set_refmap_bit(request->node_idx, res);
|
|
mlog(0, "%s:%.*s: setting bit %u in refmap\n",
|
|
dlm->name, namelen, name,
|
|
request->node_idx);
|
|
} else
|
|
response = DLM_MASTER_RESP_NO;
|
|
} else {
|
|
// mlog(0, "this node is attempting to "
|
|
// "master lockres\n");
|
|
response = DLM_MASTER_RESP_MAYBE;
|
|
}
|
|
if (set_maybe)
|
|
set_bit(request->node_idx, tmpmle->maybe_map);
|
|
spin_unlock(&tmpmle->spinlock);
|
|
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* keep the mle attached to heartbeat events */
|
|
dlm_put_mle(tmpmle);
|
|
if (mle)
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
goto send_response;
|
|
}
|
|
|
|
/*
|
|
* lockres doesn't exist on this node
|
|
* if there is an MLE_BLOCK, return NO
|
|
* if there is an MLE_MASTER, return MAYBE
|
|
* otherwise, add an MLE_BLOCK, return NO
|
|
*/
|
|
spin_lock(&dlm->master_lock);
|
|
found = dlm_find_mle(dlm, &tmpmle, name, namelen);
|
|
if (!found) {
|
|
/* this lockid has never been seen on this node yet */
|
|
// mlog(0, "no mle found\n");
|
|
if (!mle) {
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
mle = (struct dlm_master_list_entry *)
|
|
kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
|
|
if (!mle) {
|
|
response = DLM_MASTER_RESP_ERROR;
|
|
mlog_errno(-ENOMEM);
|
|
goto send_response;
|
|
}
|
|
goto way_up_top;
|
|
}
|
|
|
|
// mlog(0, "this is second time thru, already allocated, "
|
|
// "add the block.\n");
|
|
dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, name, namelen);
|
|
set_bit(request->node_idx, mle->maybe_map);
|
|
list_add(&mle->list, &dlm->master_list);
|
|
response = DLM_MASTER_RESP_NO;
|
|
} else {
|
|
// mlog(0, "mle was found\n");
|
|
set_maybe = 1;
|
|
spin_lock(&tmpmle->spinlock);
|
|
if (tmpmle->master == dlm->node_num) {
|
|
mlog(ML_ERROR, "no lockres, but an mle with this node as master!\n");
|
|
BUG();
|
|
}
|
|
if (tmpmle->type == DLM_MLE_BLOCK)
|
|
response = DLM_MASTER_RESP_NO;
|
|
else if (tmpmle->type == DLM_MLE_MIGRATION) {
|
|
mlog(0, "migration mle was found (%u->%u)\n",
|
|
tmpmle->master, tmpmle->new_master);
|
|
/* real master can respond on its own */
|
|
response = DLM_MASTER_RESP_NO;
|
|
} else
|
|
response = DLM_MASTER_RESP_MAYBE;
|
|
if (set_maybe)
|
|
set_bit(request->node_idx, tmpmle->maybe_map);
|
|
spin_unlock(&tmpmle->spinlock);
|
|
}
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
if (found) {
|
|
/* keep the mle attached to heartbeat events */
|
|
dlm_put_mle(tmpmle);
|
|
}
|
|
send_response:
|
|
|
|
if (dispatch_assert) {
|
|
if (response != DLM_MASTER_RESP_YES)
|
|
mlog(ML_ERROR, "invalid response %d\n", response);
|
|
if (!res) {
|
|
mlog(ML_ERROR, "bad lockres while trying to assert!\n");
|
|
BUG();
|
|
}
|
|
mlog(0, "%u is the owner of %.*s, cleaning everyone else\n",
|
|
dlm->node_num, res->lockname.len, res->lockname.name);
|
|
ret = dlm_dispatch_assert_master(dlm, res, 0, request->node_idx,
|
|
DLM_ASSERT_MASTER_MLE_CLEANUP);
|
|
if (ret < 0) {
|
|
mlog(ML_ERROR, "failed to dispatch assert master work\n");
|
|
response = DLM_MASTER_RESP_ERROR;
|
|
}
|
|
}
|
|
|
|
dlm_put(dlm);
|
|
return response;
|
|
}
|
|
|
|
/*
|
|
* DLM_ASSERT_MASTER_MSG
|
|
*/
|
|
|
|
|
|
/*
|
|
* NOTE: this can be used for debugging
|
|
* can periodically run all locks owned by this node
|
|
* and re-assert across the cluster...
|
|
*/
|
|
int dlm_do_assert_master(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
void *nodemap, u32 flags)
|
|
{
|
|
struct dlm_assert_master assert;
|
|
int to, tmpret;
|
|
struct dlm_node_iter iter;
|
|
int ret = 0;
|
|
int reassert;
|
|
const char *lockname = res->lockname.name;
|
|
unsigned int namelen = res->lockname.len;
|
|
|
|
BUG_ON(namelen > O2NM_MAX_NAME_LEN);
|
|
|
|
spin_lock(&res->spinlock);
|
|
res->state |= DLM_LOCK_RES_SETREF_INPROG;
|
|
spin_unlock(&res->spinlock);
|
|
|
|
again:
|
|
reassert = 0;
|
|
|
|
/* note that if this nodemap is empty, it returns 0 */
|
|
dlm_node_iter_init(nodemap, &iter);
|
|
while ((to = dlm_node_iter_next(&iter)) >= 0) {
|
|
int r = 0;
|
|
struct dlm_master_list_entry *mle = NULL;
|
|
|
|
mlog(0, "sending assert master to %d (%.*s)\n", to,
|
|
namelen, lockname);
|
|
memset(&assert, 0, sizeof(assert));
|
|
assert.node_idx = dlm->node_num;
|
|
assert.namelen = namelen;
|
|
memcpy(assert.name, lockname, namelen);
|
|
assert.flags = cpu_to_be32(flags);
|
|
|
|
tmpret = o2net_send_message(DLM_ASSERT_MASTER_MSG, dlm->key,
|
|
&assert, sizeof(assert), to, &r);
|
|
if (tmpret < 0) {
|
|
mlog(0, "assert_master returned %d!\n", tmpret);
|
|
if (!dlm_is_host_down(tmpret)) {
|
|
mlog(ML_ERROR, "unhandled error=%d!\n", tmpret);
|
|
BUG();
|
|
}
|
|
/* a node died. finish out the rest of the nodes. */
|
|
mlog(0, "link to %d went down!\n", to);
|
|
/* any nonzero status return will do */
|
|
ret = tmpret;
|
|
r = 0;
|
|
} else if (r < 0) {
|
|
/* ok, something horribly messed. kill thyself. */
|
|
mlog(ML_ERROR,"during assert master of %.*s to %u, "
|
|
"got %d.\n", namelen, lockname, to, r);
|
|
spin_lock(&dlm->spinlock);
|
|
spin_lock(&dlm->master_lock);
|
|
if (dlm_find_mle(dlm, &mle, (char *)lockname,
|
|
namelen)) {
|
|
dlm_print_one_mle(mle);
|
|
__dlm_put_mle(mle);
|
|
}
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
BUG();
|
|
}
|
|
|
|
if (r & DLM_ASSERT_RESPONSE_REASSERT &&
|
|
!(r & DLM_ASSERT_RESPONSE_MASTERY_REF)) {
|
|
mlog(ML_ERROR, "%.*s: very strange, "
|
|
"master MLE but no lockres on %u\n",
|
|
namelen, lockname, to);
|
|
}
|
|
|
|
if (r & DLM_ASSERT_RESPONSE_REASSERT) {
|
|
mlog(0, "%.*s: node %u create mles on other "
|
|
"nodes and requests a re-assert\n",
|
|
namelen, lockname, to);
|
|
reassert = 1;
|
|
}
|
|
if (r & DLM_ASSERT_RESPONSE_MASTERY_REF) {
|
|
mlog(0, "%.*s: node %u has a reference to this "
|
|
"lockres, set the bit in the refmap\n",
|
|
namelen, lockname, to);
|
|
spin_lock(&res->spinlock);
|
|
dlm_lockres_set_refmap_bit(to, res);
|
|
spin_unlock(&res->spinlock);
|
|
}
|
|
}
|
|
|
|
if (reassert)
|
|
goto again;
|
|
|
|
spin_lock(&res->spinlock);
|
|
res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
|
|
spin_unlock(&res->spinlock);
|
|
wake_up(&res->wq);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* locks that can be taken here:
|
|
* dlm->spinlock
|
|
* res->spinlock
|
|
* mle->spinlock
|
|
* dlm->master_list
|
|
*
|
|
* if possible, TRIM THIS DOWN!!!
|
|
*/
|
|
int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
|
|
void **ret_data)
|
|
{
|
|
struct dlm_ctxt *dlm = data;
|
|
struct dlm_master_list_entry *mle = NULL;
|
|
struct dlm_assert_master *assert = (struct dlm_assert_master *)msg->buf;
|
|
struct dlm_lock_resource *res = NULL;
|
|
char *name;
|
|
unsigned int namelen, hash;
|
|
u32 flags;
|
|
int master_request = 0, have_lockres_ref = 0;
|
|
int ret = 0;
|
|
|
|
if (!dlm_grab(dlm))
|
|
return 0;
|
|
|
|
name = assert->name;
|
|
namelen = assert->namelen;
|
|
hash = dlm_lockid_hash(name, namelen);
|
|
flags = be32_to_cpu(assert->flags);
|
|
|
|
if (namelen > DLM_LOCKID_NAME_MAX) {
|
|
mlog(ML_ERROR, "Invalid name length!");
|
|
goto done;
|
|
}
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
|
|
if (flags)
|
|
mlog(0, "assert_master with flags: %u\n", flags);
|
|
|
|
/* find the MLE */
|
|
spin_lock(&dlm->master_lock);
|
|
if (!dlm_find_mle(dlm, &mle, name, namelen)) {
|
|
/* not an error, could be master just re-asserting */
|
|
mlog(0, "just got an assert_master from %u, but no "
|
|
"MLE for it! (%.*s)\n", assert->node_idx,
|
|
namelen, name);
|
|
} else {
|
|
int bit = find_next_bit (mle->maybe_map, O2NM_MAX_NODES, 0);
|
|
if (bit >= O2NM_MAX_NODES) {
|
|
/* not necessarily an error, though less likely.
|
|
* could be master just re-asserting. */
|
|
mlog(0, "no bits set in the maybe_map, but %u "
|
|
"is asserting! (%.*s)\n", assert->node_idx,
|
|
namelen, name);
|
|
} else if (bit != assert->node_idx) {
|
|
if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) {
|
|
mlog(0, "master %u was found, %u should "
|
|
"back off\n", assert->node_idx, bit);
|
|
} else {
|
|
/* with the fix for bug 569, a higher node
|
|
* number winning the mastery will respond
|
|
* YES to mastery requests, but this node
|
|
* had no way of knowing. let it pass. */
|
|
mlog(0, "%u is the lowest node, "
|
|
"%u is asserting. (%.*s) %u must "
|
|
"have begun after %u won.\n", bit,
|
|
assert->node_idx, namelen, name, bit,
|
|
assert->node_idx);
|
|
}
|
|
}
|
|
if (mle->type == DLM_MLE_MIGRATION) {
|
|
if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) {
|
|
mlog(0, "%s:%.*s: got cleanup assert"
|
|
" from %u for migration\n",
|
|
dlm->name, namelen, name,
|
|
assert->node_idx);
|
|
} else if (!(flags & DLM_ASSERT_MASTER_FINISH_MIGRATION)) {
|
|
mlog(0, "%s:%.*s: got unrelated assert"
|
|
" from %u for migration, ignoring\n",
|
|
dlm->name, namelen, name,
|
|
assert->node_idx);
|
|
__dlm_put_mle(mle);
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
goto done;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock(&dlm->master_lock);
|
|
|
|
/* ok everything checks out with the MLE
|
|
* now check to see if there is a lockres */
|
|
res = __dlm_lookup_lockres(dlm, name, namelen, hash);
|
|
if (res) {
|
|
spin_lock(&res->spinlock);
|
|
if (res->state & DLM_LOCK_RES_RECOVERING) {
|
|
mlog(ML_ERROR, "%u asserting but %.*s is "
|
|
"RECOVERING!\n", assert->node_idx, namelen, name);
|
|
goto kill;
|
|
}
|
|
if (!mle) {
|
|
if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN &&
|
|
res->owner != assert->node_idx) {
|
|
mlog(ML_ERROR, "assert_master from "
|
|
"%u, but current owner is "
|
|
"%u! (%.*s)\n",
|
|
assert->node_idx, res->owner,
|
|
namelen, name);
|
|
goto kill;
|
|
}
|
|
} else if (mle->type != DLM_MLE_MIGRATION) {
|
|
if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
/* owner is just re-asserting */
|
|
if (res->owner == assert->node_idx) {
|
|
mlog(0, "owner %u re-asserting on "
|
|
"lock %.*s\n", assert->node_idx,
|
|
namelen, name);
|
|
goto ok;
|
|
}
|
|
mlog(ML_ERROR, "got assert_master from "
|
|
"node %u, but %u is the owner! "
|
|
"(%.*s)\n", assert->node_idx,
|
|
res->owner, namelen, name);
|
|
goto kill;
|
|
}
|
|
if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) {
|
|
mlog(ML_ERROR, "got assert from %u, but lock "
|
|
"with no owner should be "
|
|
"in-progress! (%.*s)\n",
|
|
assert->node_idx,
|
|
namelen, name);
|
|
goto kill;
|
|
}
|
|
} else /* mle->type == DLM_MLE_MIGRATION */ {
|
|
/* should only be getting an assert from new master */
|
|
if (assert->node_idx != mle->new_master) {
|
|
mlog(ML_ERROR, "got assert from %u, but "
|
|
"new master is %u, and old master "
|
|
"was %u (%.*s)\n",
|
|
assert->node_idx, mle->new_master,
|
|
mle->master, namelen, name);
|
|
goto kill;
|
|
}
|
|
|
|
}
|
|
ok:
|
|
spin_unlock(&res->spinlock);
|
|
}
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
// mlog(0, "woo! got an assert_master from node %u!\n",
|
|
// assert->node_idx);
|
|
if (mle) {
|
|
int extra_ref = 0;
|
|
int nn = -1;
|
|
int rr, err = 0;
|
|
|
|
spin_lock(&mle->spinlock);
|
|
if (mle->type == DLM_MLE_BLOCK || mle->type == DLM_MLE_MIGRATION)
|
|
extra_ref = 1;
|
|
else {
|
|
/* MASTER mle: if any bits set in the response map
|
|
* then the calling node needs to re-assert to clear
|
|
* up nodes that this node contacted */
|
|
while ((nn = find_next_bit (mle->response_map, O2NM_MAX_NODES,
|
|
nn+1)) < O2NM_MAX_NODES) {
|
|
if (nn != dlm->node_num && nn != assert->node_idx)
|
|
master_request = 1;
|
|
}
|
|
}
|
|
mle->master = assert->node_idx;
|
|
atomic_set(&mle->woken, 1);
|
|
wake_up(&mle->wq);
|
|
spin_unlock(&mle->spinlock);
|
|
|
|
if (res) {
|
|
int wake = 0;
|
|
spin_lock(&res->spinlock);
|
|
if (mle->type == DLM_MLE_MIGRATION) {
|
|
mlog(0, "finishing off migration of lockres %.*s, "
|
|
"from %u to %u\n",
|
|
res->lockname.len, res->lockname.name,
|
|
dlm->node_num, mle->new_master);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
wake = 1;
|
|
dlm_change_lockres_owner(dlm, res, mle->new_master);
|
|
BUG_ON(res->state & DLM_LOCK_RES_DIRTY);
|
|
} else {
|
|
dlm_change_lockres_owner(dlm, res, mle->master);
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
have_lockres_ref = 1;
|
|
if (wake)
|
|
wake_up(&res->wq);
|
|
}
|
|
|
|
/* master is known, detach if not already detached.
|
|
* ensures that only one assert_master call will happen
|
|
* on this mle. */
|
|
spin_lock(&dlm->spinlock);
|
|
spin_lock(&dlm->master_lock);
|
|
|
|
rr = atomic_read(&mle->mle_refs.refcount);
|
|
if (mle->inuse > 0) {
|
|
if (extra_ref && rr < 3)
|
|
err = 1;
|
|
else if (!extra_ref && rr < 2)
|
|
err = 1;
|
|
} else {
|
|
if (extra_ref && rr < 2)
|
|
err = 1;
|
|
else if (!extra_ref && rr < 1)
|
|
err = 1;
|
|
}
|
|
if (err) {
|
|
mlog(ML_ERROR, "%s:%.*s: got assert master from %u "
|
|
"that will mess up this node, refs=%d, extra=%d, "
|
|
"inuse=%d\n", dlm->name, namelen, name,
|
|
assert->node_idx, rr, extra_ref, mle->inuse);
|
|
dlm_print_one_mle(mle);
|
|
}
|
|
list_del_init(&mle->list);
|
|
__dlm_mle_detach_hb_events(dlm, mle);
|
|
__dlm_put_mle(mle);
|
|
if (extra_ref) {
|
|
/* the assert master message now balances the extra
|
|
* ref given by the master / migration request message.
|
|
* if this is the last put, it will be removed
|
|
* from the list. */
|
|
__dlm_put_mle(mle);
|
|
}
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
} else if (res) {
|
|
if (res->owner != assert->node_idx) {
|
|
mlog(0, "assert_master from %u, but current "
|
|
"owner is %u (%.*s), no mle\n", assert->node_idx,
|
|
res->owner, namelen, name);
|
|
}
|
|
}
|
|
|
|
done:
|
|
ret = 0;
|
|
if (res) {
|
|
spin_lock(&res->spinlock);
|
|
res->state |= DLM_LOCK_RES_SETREF_INPROG;
|
|
spin_unlock(&res->spinlock);
|
|
*ret_data = (void *)res;
|
|
}
|
|
dlm_put(dlm);
|
|
if (master_request) {
|
|
mlog(0, "need to tell master to reassert\n");
|
|
/* positive. negative would shoot down the node. */
|
|
ret |= DLM_ASSERT_RESPONSE_REASSERT;
|
|
if (!have_lockres_ref) {
|
|
mlog(ML_ERROR, "strange, got assert from %u, MASTER "
|
|
"mle present here for %s:%.*s, but no lockres!\n",
|
|
assert->node_idx, dlm->name, namelen, name);
|
|
}
|
|
}
|
|
if (have_lockres_ref) {
|
|
/* let the master know we have a reference to the lockres */
|
|
ret |= DLM_ASSERT_RESPONSE_MASTERY_REF;
|
|
mlog(0, "%s:%.*s: got assert from %u, need a ref\n",
|
|
dlm->name, namelen, name, assert->node_idx);
|
|
}
|
|
return ret;
|
|
|
|
kill:
|
|
/* kill the caller! */
|
|
mlog(ML_ERROR, "Bad message received from another node. Dumping state "
|
|
"and killing the other node now! This node is OK and can continue.\n");
|
|
__dlm_print_one_lock_resource(res);
|
|
spin_unlock(&res->spinlock);
|
|
spin_unlock(&dlm->spinlock);
|
|
*ret_data = (void *)res;
|
|
dlm_put(dlm);
|
|
return -EINVAL;
|
|
}
|
|
|
|
void dlm_assert_master_post_handler(int status, void *data, void *ret_data)
|
|
{
|
|
struct dlm_lock_resource *res = (struct dlm_lock_resource *)ret_data;
|
|
|
|
if (ret_data) {
|
|
spin_lock(&res->spinlock);
|
|
res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
|
|
spin_unlock(&res->spinlock);
|
|
wake_up(&res->wq);
|
|
dlm_lockres_put(res);
|
|
}
|
|
return;
|
|
}
|
|
|
|
int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
int ignore_higher, u8 request_from, u32 flags)
|
|
{
|
|
struct dlm_work_item *item;
|
|
item = kzalloc(sizeof(*item), GFP_NOFS);
|
|
if (!item)
|
|
return -ENOMEM;
|
|
|
|
|
|
/* queue up work for dlm_assert_master_worker */
|
|
dlm_grab(dlm); /* get an extra ref for the work item */
|
|
dlm_init_work_item(dlm, item, dlm_assert_master_worker, NULL);
|
|
item->u.am.lockres = res; /* already have a ref */
|
|
/* can optionally ignore node numbers higher than this node */
|
|
item->u.am.ignore_higher = ignore_higher;
|
|
item->u.am.request_from = request_from;
|
|
item->u.am.flags = flags;
|
|
|
|
if (ignore_higher)
|
|
mlog(0, "IGNORE HIGHER: %.*s\n", res->lockname.len,
|
|
res->lockname.name);
|
|
|
|
spin_lock(&dlm->work_lock);
|
|
list_add_tail(&item->list, &dlm->work_list);
|
|
spin_unlock(&dlm->work_lock);
|
|
|
|
queue_work(dlm->dlm_worker, &dlm->dispatched_work);
|
|
return 0;
|
|
}
|
|
|
|
static void dlm_assert_master_worker(struct dlm_work_item *item, void *data)
|
|
{
|
|
struct dlm_ctxt *dlm = data;
|
|
int ret = 0;
|
|
struct dlm_lock_resource *res;
|
|
unsigned long nodemap[BITS_TO_LONGS(O2NM_MAX_NODES)];
|
|
int ignore_higher;
|
|
int bit;
|
|
u8 request_from;
|
|
u32 flags;
|
|
|
|
dlm = item->dlm;
|
|
res = item->u.am.lockres;
|
|
ignore_higher = item->u.am.ignore_higher;
|
|
request_from = item->u.am.request_from;
|
|
flags = item->u.am.flags;
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
memcpy(nodemap, dlm->domain_map, sizeof(nodemap));
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
clear_bit(dlm->node_num, nodemap);
|
|
if (ignore_higher) {
|
|
/* if is this just to clear up mles for nodes below
|
|
* this node, do not send the message to the original
|
|
* caller or any node number higher than this */
|
|
clear_bit(request_from, nodemap);
|
|
bit = dlm->node_num;
|
|
while (1) {
|
|
bit = find_next_bit(nodemap, O2NM_MAX_NODES,
|
|
bit+1);
|
|
if (bit >= O2NM_MAX_NODES)
|
|
break;
|
|
clear_bit(bit, nodemap);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we're migrating this lock to someone else, we are no
|
|
* longer allowed to assert out own mastery. OTOH, we need to
|
|
* prevent migration from starting while we're still asserting
|
|
* our dominance. The reserved ast delays migration.
|
|
*/
|
|
spin_lock(&res->spinlock);
|
|
if (res->state & DLM_LOCK_RES_MIGRATING) {
|
|
mlog(0, "Someone asked us to assert mastery, but we're "
|
|
"in the middle of migration. Skipping assert, "
|
|
"the new master will handle that.\n");
|
|
spin_unlock(&res->spinlock);
|
|
goto put;
|
|
} else
|
|
__dlm_lockres_reserve_ast(res);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* this call now finishes out the nodemap
|
|
* even if one or more nodes die */
|
|
mlog(0, "worker about to master %.*s here, this=%u\n",
|
|
res->lockname.len, res->lockname.name, dlm->node_num);
|
|
ret = dlm_do_assert_master(dlm, res, nodemap, flags);
|
|
if (ret < 0) {
|
|
/* no need to restart, we are done */
|
|
if (!dlm_is_host_down(ret))
|
|
mlog_errno(ret);
|
|
}
|
|
|
|
/* Ok, we've asserted ourselves. Let's let migration start. */
|
|
dlm_lockres_release_ast(dlm, res);
|
|
|
|
put:
|
|
dlm_lockres_put(res);
|
|
|
|
mlog(0, "finished with dlm_assert_master_worker\n");
|
|
}
|
|
|
|
/* SPECIAL CASE for the $RECOVERY lock used by the recovery thread.
|
|
* We cannot wait for node recovery to complete to begin mastering this
|
|
* lockres because this lockres is used to kick off recovery! ;-)
|
|
* So, do a pre-check on all living nodes to see if any of those nodes
|
|
* think that $RECOVERY is currently mastered by a dead node. If so,
|
|
* we wait a short time to allow that node to get notified by its own
|
|
* heartbeat stack, then check again. All $RECOVERY lock resources
|
|
* mastered by dead nodes are purged when the hearbeat callback is
|
|
* fired, so we can know for sure that it is safe to continue once
|
|
* the node returns a live node or no node. */
|
|
static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res)
|
|
{
|
|
struct dlm_node_iter iter;
|
|
int nodenum;
|
|
int ret = 0;
|
|
u8 master = DLM_LOCK_RES_OWNER_UNKNOWN;
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
dlm_node_iter_init(dlm->domain_map, &iter);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
|
|
/* do not send to self */
|
|
if (nodenum == dlm->node_num)
|
|
continue;
|
|
ret = dlm_do_master_requery(dlm, res, nodenum, &master);
|
|
if (ret < 0) {
|
|
mlog_errno(ret);
|
|
if (!dlm_is_host_down(ret))
|
|
BUG();
|
|
/* host is down, so answer for that node would be
|
|
* DLM_LOCK_RES_OWNER_UNKNOWN. continue. */
|
|
ret = 0;
|
|
}
|
|
|
|
if (master != DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
/* check to see if this master is in the recovery map */
|
|
spin_lock(&dlm->spinlock);
|
|
if (test_bit(master, dlm->recovery_map)) {
|
|
mlog(ML_NOTICE, "%s: node %u has not seen "
|
|
"node %u go down yet, and thinks the "
|
|
"dead node is mastering the recovery "
|
|
"lock. must wait.\n", dlm->name,
|
|
nodenum, master);
|
|
ret = -EAGAIN;
|
|
}
|
|
spin_unlock(&dlm->spinlock);
|
|
mlog(0, "%s: reco lock master is %u\n", dlm->name,
|
|
master);
|
|
break;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* DLM_DEREF_LOCKRES_MSG
|
|
*/
|
|
|
|
int dlm_drop_lockres_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
|
|
{
|
|
struct dlm_deref_lockres deref;
|
|
int ret = 0, r;
|
|
const char *lockname;
|
|
unsigned int namelen;
|
|
|
|
lockname = res->lockname.name;
|
|
namelen = res->lockname.len;
|
|
BUG_ON(namelen > O2NM_MAX_NAME_LEN);
|
|
|
|
mlog(0, "%s:%.*s: sending deref to %d\n",
|
|
dlm->name, namelen, lockname, res->owner);
|
|
memset(&deref, 0, sizeof(deref));
|
|
deref.node_idx = dlm->node_num;
|
|
deref.namelen = namelen;
|
|
memcpy(deref.name, lockname, namelen);
|
|
|
|
ret = o2net_send_message(DLM_DEREF_LOCKRES_MSG, dlm->key,
|
|
&deref, sizeof(deref), res->owner, &r);
|
|
if (ret < 0)
|
|
mlog_errno(ret);
|
|
else if (r < 0) {
|
|
/* BAD. other node says I did not have a ref. */
|
|
mlog(ML_ERROR,"while dropping ref on %s:%.*s "
|
|
"(master=%u) got %d.\n", dlm->name, namelen,
|
|
lockname, res->owner, r);
|
|
dlm_print_one_lock_resource(res);
|
|
BUG();
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
|
|
void **ret_data)
|
|
{
|
|
struct dlm_ctxt *dlm = data;
|
|
struct dlm_deref_lockres *deref = (struct dlm_deref_lockres *)msg->buf;
|
|
struct dlm_lock_resource *res = NULL;
|
|
char *name;
|
|
unsigned int namelen;
|
|
int ret = -EINVAL;
|
|
u8 node;
|
|
unsigned int hash;
|
|
struct dlm_work_item *item;
|
|
int cleared = 0;
|
|
int dispatch = 0;
|
|
|
|
if (!dlm_grab(dlm))
|
|
return 0;
|
|
|
|
name = deref->name;
|
|
namelen = deref->namelen;
|
|
node = deref->node_idx;
|
|
|
|
if (namelen > DLM_LOCKID_NAME_MAX) {
|
|
mlog(ML_ERROR, "Invalid name length!");
|
|
goto done;
|
|
}
|
|
if (deref->node_idx >= O2NM_MAX_NODES) {
|
|
mlog(ML_ERROR, "Invalid node number: %u\n", node);
|
|
goto done;
|
|
}
|
|
|
|
hash = dlm_lockid_hash(name, namelen);
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
res = __dlm_lookup_lockres_full(dlm, name, namelen, hash);
|
|
if (!res) {
|
|
spin_unlock(&dlm->spinlock);
|
|
mlog(ML_ERROR, "%s:%.*s: bad lockres name\n",
|
|
dlm->name, namelen, name);
|
|
goto done;
|
|
}
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
spin_lock(&res->spinlock);
|
|
if (res->state & DLM_LOCK_RES_SETREF_INPROG)
|
|
dispatch = 1;
|
|
else {
|
|
BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
|
|
if (test_bit(node, res->refmap)) {
|
|
dlm_lockres_clear_refmap_bit(node, res);
|
|
cleared = 1;
|
|
}
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
|
|
if (!dispatch) {
|
|
if (cleared)
|
|
dlm_lockres_calc_usage(dlm, res);
|
|
else {
|
|
mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
|
|
"but it is already dropped!\n", dlm->name,
|
|
res->lockname.len, res->lockname.name, node);
|
|
__dlm_print_one_lock_resource(res);
|
|
}
|
|
ret = 0;
|
|
goto done;
|
|
}
|
|
|
|
item = kzalloc(sizeof(*item), GFP_NOFS);
|
|
if (!item) {
|
|
ret = -ENOMEM;
|
|
mlog_errno(ret);
|
|
goto done;
|
|
}
|
|
|
|
dlm_init_work_item(dlm, item, dlm_deref_lockres_worker, NULL);
|
|
item->u.dl.deref_res = res;
|
|
item->u.dl.deref_node = node;
|
|
|
|
spin_lock(&dlm->work_lock);
|
|
list_add_tail(&item->list, &dlm->work_list);
|
|
spin_unlock(&dlm->work_lock);
|
|
|
|
queue_work(dlm->dlm_worker, &dlm->dispatched_work);
|
|
return 0;
|
|
|
|
done:
|
|
if (res)
|
|
dlm_lockres_put(res);
|
|
dlm_put(dlm);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data)
|
|
{
|
|
struct dlm_ctxt *dlm;
|
|
struct dlm_lock_resource *res;
|
|
u8 node;
|
|
u8 cleared = 0;
|
|
|
|
dlm = item->dlm;
|
|
res = item->u.dl.deref_res;
|
|
node = item->u.dl.deref_node;
|
|
|
|
spin_lock(&res->spinlock);
|
|
BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
|
|
if (test_bit(node, res->refmap)) {
|
|
__dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG);
|
|
dlm_lockres_clear_refmap_bit(node, res);
|
|
cleared = 1;
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
|
|
if (cleared) {
|
|
mlog(0, "%s:%.*s node %u ref dropped in dispatch\n",
|
|
dlm->name, res->lockname.len, res->lockname.name, node);
|
|
dlm_lockres_calc_usage(dlm, res);
|
|
} else {
|
|
mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
|
|
"but it is already dropped!\n", dlm->name,
|
|
res->lockname.len, res->lockname.name, node);
|
|
__dlm_print_one_lock_resource(res);
|
|
}
|
|
|
|
dlm_lockres_put(res);
|
|
}
|
|
|
|
/* Checks whether the lockres can be migrated. Returns 0 if yes, < 0
|
|
* if not. If 0, numlocks is set to the number of locks in the lockres.
|
|
*/
|
|
static int dlm_is_lockres_migrateable(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
int *numlocks)
|
|
{
|
|
int ret;
|
|
int i;
|
|
int count = 0;
|
|
struct list_head *queue, *iter;
|
|
struct dlm_lock *lock;
|
|
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
ret = -EINVAL;
|
|
if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
|
|
mlog(0, "cannot migrate lockres with unknown owner!\n");
|
|
goto leave;
|
|
}
|
|
|
|
if (res->owner != dlm->node_num) {
|
|
mlog(0, "cannot migrate lockres this node doesn't own!\n");
|
|
goto leave;
|
|
}
|
|
|
|
ret = 0;
|
|
queue = &res->granted;
|
|
for (i = 0; i < 3; i++) {
|
|
list_for_each(iter, queue) {
|
|
lock = list_entry(iter, struct dlm_lock, list);
|
|
++count;
|
|
if (lock->ml.node == dlm->node_num) {
|
|
mlog(0, "found a lock owned by this node still "
|
|
"on the %s queue! will not migrate this "
|
|
"lockres\n", (i == 0 ? "granted" :
|
|
(i == 1 ? "converting" :
|
|
"blocked")));
|
|
ret = -ENOTEMPTY;
|
|
goto leave;
|
|
}
|
|
}
|
|
queue++;
|
|
}
|
|
|
|
*numlocks = count;
|
|
mlog(0, "migrateable lockres having %d locks\n", *numlocks);
|
|
|
|
leave:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* DLM_MIGRATE_LOCKRES
|
|
*/
|
|
|
|
|
|
static int dlm_migrate_lockres(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
u8 target)
|
|
{
|
|
struct dlm_master_list_entry *mle = NULL;
|
|
struct dlm_master_list_entry *oldmle = NULL;
|
|
struct dlm_migratable_lockres *mres = NULL;
|
|
int ret = 0;
|
|
const char *name;
|
|
unsigned int namelen;
|
|
int mle_added = 0;
|
|
int numlocks;
|
|
int wake = 0;
|
|
|
|
if (!dlm_grab(dlm))
|
|
return -EINVAL;
|
|
|
|
name = res->lockname.name;
|
|
namelen = res->lockname.len;
|
|
|
|
mlog(0, "migrating %.*s to %u\n", namelen, name, target);
|
|
|
|
/*
|
|
* ensure this lockres is a proper candidate for migration
|
|
*/
|
|
spin_lock(&res->spinlock);
|
|
ret = dlm_is_lockres_migrateable(dlm, res, &numlocks);
|
|
if (ret < 0) {
|
|
spin_unlock(&res->spinlock);
|
|
goto leave;
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* no work to do */
|
|
if (numlocks == 0) {
|
|
mlog(0, "no locks were found on this lockres! done!\n");
|
|
goto leave;
|
|
}
|
|
|
|
/*
|
|
* preallocate up front
|
|
* if this fails, abort
|
|
*/
|
|
|
|
ret = -ENOMEM;
|
|
mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_NOFS);
|
|
if (!mres) {
|
|
mlog_errno(ret);
|
|
goto leave;
|
|
}
|
|
|
|
mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache,
|
|
GFP_NOFS);
|
|
if (!mle) {
|
|
mlog_errno(ret);
|
|
goto leave;
|
|
}
|
|
ret = 0;
|
|
|
|
/*
|
|
* find a node to migrate the lockres to
|
|
*/
|
|
|
|
mlog(0, "picking a migration node\n");
|
|
spin_lock(&dlm->spinlock);
|
|
/* pick a new node */
|
|
if (!test_bit(target, dlm->domain_map) ||
|
|
target >= O2NM_MAX_NODES) {
|
|
target = dlm_pick_migration_target(dlm, res);
|
|
}
|
|
mlog(0, "node %u chosen for migration\n", target);
|
|
|
|
if (target >= O2NM_MAX_NODES ||
|
|
!test_bit(target, dlm->domain_map)) {
|
|
/* target chosen is not alive */
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
if (ret) {
|
|
spin_unlock(&dlm->spinlock);
|
|
goto fail;
|
|
}
|
|
|
|
mlog(0, "continuing with target = %u\n", target);
|
|
|
|
/*
|
|
* clear any existing master requests and
|
|
* add the migration mle to the list
|
|
*/
|
|
spin_lock(&dlm->master_lock);
|
|
ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, name,
|
|
namelen, target, dlm->node_num);
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
if (ret == -EEXIST) {
|
|
mlog(0, "another process is already migrating it\n");
|
|
goto fail;
|
|
}
|
|
mle_added = 1;
|
|
|
|
/*
|
|
* set the MIGRATING flag and flush asts
|
|
* if we fail after this we need to re-dirty the lockres
|
|
*/
|
|
if (dlm_mark_lockres_migrating(dlm, res, target) < 0) {
|
|
mlog(ML_ERROR, "tried to migrate %.*s to %u, but "
|
|
"the target went down.\n", res->lockname.len,
|
|
res->lockname.name, target);
|
|
spin_lock(&res->spinlock);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
wake = 1;
|
|
spin_unlock(&res->spinlock);
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
fail:
|
|
if (oldmle) {
|
|
/* master is known, detach if not already detached */
|
|
dlm_mle_detach_hb_events(dlm, oldmle);
|
|
dlm_put_mle(oldmle);
|
|
}
|
|
|
|
if (ret < 0) {
|
|
if (mle_added) {
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle(mle);
|
|
} else if (mle) {
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
}
|
|
goto leave;
|
|
}
|
|
|
|
/*
|
|
* at this point, we have a migration target, an mle
|
|
* in the master list, and the MIGRATING flag set on
|
|
* the lockres
|
|
*/
|
|
|
|
/* now that remote nodes are spinning on the MIGRATING flag,
|
|
* ensure that all assert_master work is flushed. */
|
|
flush_workqueue(dlm->dlm_worker);
|
|
|
|
/* get an extra reference on the mle.
|
|
* otherwise the assert_master from the new
|
|
* master will destroy this.
|
|
* also, make sure that all callers of dlm_get_mle
|
|
* take both dlm->spinlock and dlm->master_lock */
|
|
spin_lock(&dlm->spinlock);
|
|
spin_lock(&dlm->master_lock);
|
|
dlm_get_mle_inuse(mle);
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/* notify new node and send all lock state */
|
|
/* call send_one_lockres with migration flag.
|
|
* this serves as notice to the target node that a
|
|
* migration is starting. */
|
|
ret = dlm_send_one_lockres(dlm, res, mres, target,
|
|
DLM_MRES_MIGRATION);
|
|
|
|
if (ret < 0) {
|
|
mlog(0, "migration to node %u failed with %d\n",
|
|
target, ret);
|
|
/* migration failed, detach and clean up mle */
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle(mle);
|
|
dlm_put_mle_inuse(mle);
|
|
spin_lock(&res->spinlock);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
wake = 1;
|
|
spin_unlock(&res->spinlock);
|
|
goto leave;
|
|
}
|
|
|
|
/* at this point, the target sends a message to all nodes,
|
|
* (using dlm_do_migrate_request). this node is skipped since
|
|
* we had to put an mle in the list to begin the process. this
|
|
* node now waits for target to do an assert master. this node
|
|
* will be the last one notified, ensuring that the migration
|
|
* is complete everywhere. if the target dies while this is
|
|
* going on, some nodes could potentially see the target as the
|
|
* master, so it is important that my recovery finds the migration
|
|
* mle and sets the master to UNKNONWN. */
|
|
|
|
|
|
/* wait for new node to assert master */
|
|
while (1) {
|
|
ret = wait_event_interruptible_timeout(mle->wq,
|
|
(atomic_read(&mle->woken) == 1),
|
|
msecs_to_jiffies(5000));
|
|
|
|
if (ret >= 0) {
|
|
if (atomic_read(&mle->woken) == 1 ||
|
|
res->owner == target)
|
|
break;
|
|
|
|
mlog(0, "%s:%.*s: timed out during migration\n",
|
|
dlm->name, res->lockname.len, res->lockname.name);
|
|
/* avoid hang during shutdown when migrating lockres
|
|
* to a node which also goes down */
|
|
if (dlm_is_node_dead(dlm, target)) {
|
|
mlog(0, "%s:%.*s: expected migration "
|
|
"target %u is no longer up, restarting\n",
|
|
dlm->name, res->lockname.len,
|
|
res->lockname.name, target);
|
|
ret = -EINVAL;
|
|
/* migration failed, detach and clean up mle */
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle(mle);
|
|
dlm_put_mle_inuse(mle);
|
|
spin_lock(&res->spinlock);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
wake = 1;
|
|
spin_unlock(&res->spinlock);
|
|
goto leave;
|
|
}
|
|
} else
|
|
mlog(0, "%s:%.*s: caught signal during migration\n",
|
|
dlm->name, res->lockname.len, res->lockname.name);
|
|
}
|
|
|
|
/* all done, set the owner, clear the flag */
|
|
spin_lock(&res->spinlock);
|
|
dlm_set_lockres_owner(dlm, res, target);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
dlm_remove_nonlocal_locks(dlm, res);
|
|
spin_unlock(&res->spinlock);
|
|
wake_up(&res->wq);
|
|
|
|
/* master is known, detach if not already detached */
|
|
dlm_mle_detach_hb_events(dlm, mle);
|
|
dlm_put_mle_inuse(mle);
|
|
ret = 0;
|
|
|
|
dlm_lockres_calc_usage(dlm, res);
|
|
|
|
leave:
|
|
/* re-dirty the lockres if we failed */
|
|
if (ret < 0)
|
|
dlm_kick_thread(dlm, res);
|
|
|
|
/* wake up waiters if the MIGRATING flag got set
|
|
* but migration failed */
|
|
if (wake)
|
|
wake_up(&res->wq);
|
|
|
|
/* TODO: cleanup */
|
|
if (mres)
|
|
free_page((unsigned long)mres);
|
|
|
|
dlm_put(dlm);
|
|
|
|
mlog(0, "returning %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
#define DLM_MIGRATION_RETRY_MS 100
|
|
|
|
/* Should be called only after beginning the domain leave process.
|
|
* There should not be any remaining locks on nonlocal lock resources,
|
|
* and there should be no local locks left on locally mastered resources.
|
|
*
|
|
* Called with the dlm spinlock held, may drop it to do migration, but
|
|
* will re-acquire before exit.
|
|
*
|
|
* Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped */
|
|
int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
|
|
{
|
|
int ret;
|
|
int lock_dropped = 0;
|
|
int numlocks;
|
|
|
|
spin_lock(&res->spinlock);
|
|
if (res->owner != dlm->node_num) {
|
|
if (!__dlm_lockres_unused(res)) {
|
|
mlog(ML_ERROR, "%s:%.*s: this node is not master, "
|
|
"trying to free this but locks remain\n",
|
|
dlm->name, res->lockname.len, res->lockname.name);
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
goto leave;
|
|
}
|
|
|
|
/* No need to migrate a lockres having no locks */
|
|
ret = dlm_is_lockres_migrateable(dlm, res, &numlocks);
|
|
if (ret >= 0 && numlocks == 0) {
|
|
spin_unlock(&res->spinlock);
|
|
goto leave;
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* Wheee! Migrate lockres here! Will sleep so drop spinlock. */
|
|
spin_unlock(&dlm->spinlock);
|
|
lock_dropped = 1;
|
|
while (1) {
|
|
ret = dlm_migrate_lockres(dlm, res, O2NM_MAX_NODES);
|
|
if (ret >= 0)
|
|
break;
|
|
if (ret == -ENOTEMPTY) {
|
|
mlog(ML_ERROR, "lockres %.*s still has local locks!\n",
|
|
res->lockname.len, res->lockname.name);
|
|
BUG();
|
|
}
|
|
|
|
mlog(0, "lockres %.*s: migrate failed, "
|
|
"retrying\n", res->lockname.len,
|
|
res->lockname.name);
|
|
msleep(DLM_MIGRATION_RETRY_MS);
|
|
}
|
|
spin_lock(&dlm->spinlock);
|
|
leave:
|
|
return lock_dropped;
|
|
}
|
|
|
|
int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock)
|
|
{
|
|
int ret;
|
|
spin_lock(&dlm->ast_lock);
|
|
spin_lock(&lock->spinlock);
|
|
ret = (list_empty(&lock->bast_list) && !lock->bast_pending);
|
|
spin_unlock(&lock->spinlock);
|
|
spin_unlock(&dlm->ast_lock);
|
|
return ret;
|
|
}
|
|
|
|
static int dlm_migration_can_proceed(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
u8 mig_target)
|
|
{
|
|
int can_proceed;
|
|
spin_lock(&res->spinlock);
|
|
can_proceed = !!(res->state & DLM_LOCK_RES_MIGRATING);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* target has died, so make the caller break out of the
|
|
* wait_event, but caller must recheck the domain_map */
|
|
spin_lock(&dlm->spinlock);
|
|
if (!test_bit(mig_target, dlm->domain_map))
|
|
can_proceed = 1;
|
|
spin_unlock(&dlm->spinlock);
|
|
return can_proceed;
|
|
}
|
|
|
|
static int dlm_lockres_is_dirty(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res)
|
|
{
|
|
int ret;
|
|
spin_lock(&res->spinlock);
|
|
ret = !!(res->state & DLM_LOCK_RES_DIRTY);
|
|
spin_unlock(&res->spinlock);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
u8 target)
|
|
{
|
|
int ret = 0;
|
|
|
|
mlog(0, "dlm_mark_lockres_migrating: %.*s, from %u to %u\n",
|
|
res->lockname.len, res->lockname.name, dlm->node_num,
|
|
target);
|
|
/* need to set MIGRATING flag on lockres. this is done by
|
|
* ensuring that all asts have been flushed for this lockres. */
|
|
spin_lock(&res->spinlock);
|
|
BUG_ON(res->migration_pending);
|
|
res->migration_pending = 1;
|
|
/* strategy is to reserve an extra ast then release
|
|
* it below, letting the release do all of the work */
|
|
__dlm_lockres_reserve_ast(res);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* now flush all the pending asts */
|
|
dlm_kick_thread(dlm, res);
|
|
/* before waiting on DIRTY, block processes which may
|
|
* try to dirty the lockres before MIGRATING is set */
|
|
spin_lock(&res->spinlock);
|
|
BUG_ON(res->state & DLM_LOCK_RES_BLOCK_DIRTY);
|
|
res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
|
|
spin_unlock(&res->spinlock);
|
|
/* now wait on any pending asts and the DIRTY state */
|
|
wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
|
|
dlm_lockres_release_ast(dlm, res);
|
|
|
|
mlog(0, "about to wait on migration_wq, dirty=%s\n",
|
|
res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no");
|
|
/* if the extra ref we just put was the final one, this
|
|
* will pass thru immediately. otherwise, we need to wait
|
|
* for the last ast to finish. */
|
|
again:
|
|
ret = wait_event_interruptible_timeout(dlm->migration_wq,
|
|
dlm_migration_can_proceed(dlm, res, target),
|
|
msecs_to_jiffies(1000));
|
|
if (ret < 0) {
|
|
mlog(0, "woken again: migrating? %s, dead? %s\n",
|
|
res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no",
|
|
test_bit(target, dlm->domain_map) ? "no":"yes");
|
|
} else {
|
|
mlog(0, "all is well: migrating? %s, dead? %s\n",
|
|
res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no",
|
|
test_bit(target, dlm->domain_map) ? "no":"yes");
|
|
}
|
|
if (!dlm_migration_can_proceed(dlm, res, target)) {
|
|
mlog(0, "trying again...\n");
|
|
goto again;
|
|
}
|
|
/* now that we are sure the MIGRATING state is there, drop
|
|
* the unneded state which blocked threads trying to DIRTY */
|
|
spin_lock(&res->spinlock);
|
|
BUG_ON(!(res->state & DLM_LOCK_RES_BLOCK_DIRTY));
|
|
BUG_ON(!(res->state & DLM_LOCK_RES_MIGRATING));
|
|
res->state &= ~DLM_LOCK_RES_BLOCK_DIRTY;
|
|
spin_unlock(&res->spinlock);
|
|
|
|
/* did the target go down or die? */
|
|
spin_lock(&dlm->spinlock);
|
|
if (!test_bit(target, dlm->domain_map)) {
|
|
mlog(ML_ERROR, "aha. migration target %u just went down\n",
|
|
target);
|
|
ret = -EHOSTDOWN;
|
|
}
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/*
|
|
* at this point:
|
|
*
|
|
* o the DLM_LOCK_RES_MIGRATING flag is set
|
|
* o there are no pending asts on this lockres
|
|
* o all processes trying to reserve an ast on this
|
|
* lockres must wait for the MIGRATING flag to clear
|
|
*/
|
|
return ret;
|
|
}
|
|
|
|
/* last step in the migration process.
|
|
* original master calls this to free all of the dlm_lock
|
|
* structures that used to be for other nodes. */
|
|
static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res)
|
|
{
|
|
struct list_head *iter, *iter2;
|
|
struct list_head *queue = &res->granted;
|
|
int i, bit;
|
|
struct dlm_lock *lock;
|
|
|
|
assert_spin_locked(&res->spinlock);
|
|
|
|
BUG_ON(res->owner == dlm->node_num);
|
|
|
|
for (i=0; i<3; i++) {
|
|
list_for_each_safe(iter, iter2, queue) {
|
|
lock = list_entry (iter, struct dlm_lock, list);
|
|
if (lock->ml.node != dlm->node_num) {
|
|
mlog(0, "putting lock for node %u\n",
|
|
lock->ml.node);
|
|
/* be extra careful */
|
|
BUG_ON(!list_empty(&lock->ast_list));
|
|
BUG_ON(!list_empty(&lock->bast_list));
|
|
BUG_ON(lock->ast_pending);
|
|
BUG_ON(lock->bast_pending);
|
|
dlm_lockres_clear_refmap_bit(lock->ml.node, res);
|
|
list_del_init(&lock->list);
|
|
dlm_lock_put(lock);
|
|
}
|
|
}
|
|
queue++;
|
|
}
|
|
bit = 0;
|
|
while (1) {
|
|
bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit);
|
|
if (bit >= O2NM_MAX_NODES)
|
|
break;
|
|
/* do not clear the local node reference, if there is a
|
|
* process holding this, let it drop the ref itself */
|
|
if (bit != dlm->node_num) {
|
|
mlog(0, "%s:%.*s: node %u had a ref to this "
|
|
"migrating lockres, clearing\n", dlm->name,
|
|
res->lockname.len, res->lockname.name, bit);
|
|
dlm_lockres_clear_refmap_bit(bit, res);
|
|
}
|
|
bit++;
|
|
}
|
|
}
|
|
|
|
/* for now this is not too intelligent. we will
|
|
* need stats to make this do the right thing.
|
|
* this just finds the first lock on one of the
|
|
* queues and uses that node as the target. */
|
|
static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res)
|
|
{
|
|
int i;
|
|
struct list_head *queue = &res->granted;
|
|
struct list_head *iter;
|
|
struct dlm_lock *lock;
|
|
int nodenum;
|
|
|
|
assert_spin_locked(&dlm->spinlock);
|
|
|
|
spin_lock(&res->spinlock);
|
|
for (i=0; i<3; i++) {
|
|
list_for_each(iter, queue) {
|
|
/* up to the caller to make sure this node
|
|
* is alive */
|
|
lock = list_entry (iter, struct dlm_lock, list);
|
|
if (lock->ml.node != dlm->node_num) {
|
|
spin_unlock(&res->spinlock);
|
|
return lock->ml.node;
|
|
}
|
|
}
|
|
queue++;
|
|
}
|
|
spin_unlock(&res->spinlock);
|
|
mlog(0, "have not found a suitable target yet! checking domain map\n");
|
|
|
|
/* ok now we're getting desperate. pick anyone alive. */
|
|
nodenum = -1;
|
|
while (1) {
|
|
nodenum = find_next_bit(dlm->domain_map,
|
|
O2NM_MAX_NODES, nodenum+1);
|
|
mlog(0, "found %d in domain map\n", nodenum);
|
|
if (nodenum >= O2NM_MAX_NODES)
|
|
break;
|
|
if (nodenum != dlm->node_num) {
|
|
mlog(0, "picking %d\n", nodenum);
|
|
return nodenum;
|
|
}
|
|
}
|
|
|
|
mlog(0, "giving up. no master to migrate to\n");
|
|
return DLM_LOCK_RES_OWNER_UNKNOWN;
|
|
}
|
|
|
|
|
|
|
|
/* this is called by the new master once all lockres
|
|
* data has been received */
|
|
static int dlm_do_migrate_request(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
u8 master, u8 new_master,
|
|
struct dlm_node_iter *iter)
|
|
{
|
|
struct dlm_migrate_request migrate;
|
|
int ret, status = 0;
|
|
int nodenum;
|
|
|
|
memset(&migrate, 0, sizeof(migrate));
|
|
migrate.namelen = res->lockname.len;
|
|
memcpy(migrate.name, res->lockname.name, migrate.namelen);
|
|
migrate.new_master = new_master;
|
|
migrate.master = master;
|
|
|
|
ret = 0;
|
|
|
|
/* send message to all nodes, except the master and myself */
|
|
while ((nodenum = dlm_node_iter_next(iter)) >= 0) {
|
|
if (nodenum == master ||
|
|
nodenum == new_master)
|
|
continue;
|
|
|
|
ret = o2net_send_message(DLM_MIGRATE_REQUEST_MSG, dlm->key,
|
|
&migrate, sizeof(migrate), nodenum,
|
|
&status);
|
|
if (ret < 0)
|
|
mlog_errno(ret);
|
|
else if (status < 0) {
|
|
mlog(0, "migrate request (node %u) returned %d!\n",
|
|
nodenum, status);
|
|
ret = status;
|
|
} else if (status == DLM_MIGRATE_RESPONSE_MASTERY_REF) {
|
|
/* during the migration request we short-circuited
|
|
* the mastery of the lockres. make sure we have
|
|
* a mastery ref for nodenum */
|
|
mlog(0, "%s:%.*s: need ref for node %u\n",
|
|
dlm->name, res->lockname.len, res->lockname.name,
|
|
nodenum);
|
|
spin_lock(&res->spinlock);
|
|
dlm_lockres_set_refmap_bit(nodenum, res);
|
|
spin_unlock(&res->spinlock);
|
|
}
|
|
}
|
|
|
|
if (ret < 0)
|
|
mlog_errno(ret);
|
|
|
|
mlog(0, "returning ret=%d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/* if there is an existing mle for this lockres, we now know who the master is.
|
|
* (the one who sent us *this* message) we can clear it up right away.
|
|
* since the process that put the mle on the list still has a reference to it,
|
|
* we can unhash it now, set the master and wake the process. as a result,
|
|
* we will have no mle in the list to start with. now we can add an mle for
|
|
* the migration and this should be the only one found for those scanning the
|
|
* list. */
|
|
int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
|
|
void **ret_data)
|
|
{
|
|
struct dlm_ctxt *dlm = data;
|
|
struct dlm_lock_resource *res = NULL;
|
|
struct dlm_migrate_request *migrate = (struct dlm_migrate_request *) msg->buf;
|
|
struct dlm_master_list_entry *mle = NULL, *oldmle = NULL;
|
|
const char *name;
|
|
unsigned int namelen, hash;
|
|
int ret = 0;
|
|
|
|
if (!dlm_grab(dlm))
|
|
return -EINVAL;
|
|
|
|
name = migrate->name;
|
|
namelen = migrate->namelen;
|
|
hash = dlm_lockid_hash(name, namelen);
|
|
|
|
/* preallocate.. if this fails, abort */
|
|
mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache,
|
|
GFP_NOFS);
|
|
|
|
if (!mle) {
|
|
ret = -ENOMEM;
|
|
goto leave;
|
|
}
|
|
|
|
/* check for pre-existing lock */
|
|
spin_lock(&dlm->spinlock);
|
|
res = __dlm_lookup_lockres(dlm, name, namelen, hash);
|
|
spin_lock(&dlm->master_lock);
|
|
|
|
if (res) {
|
|
spin_lock(&res->spinlock);
|
|
if (res->state & DLM_LOCK_RES_RECOVERING) {
|
|
/* if all is working ok, this can only mean that we got
|
|
* a migrate request from a node that we now see as
|
|
* dead. what can we do here? drop it to the floor? */
|
|
spin_unlock(&res->spinlock);
|
|
mlog(ML_ERROR, "Got a migrate request, but the "
|
|
"lockres is marked as recovering!");
|
|
kmem_cache_free(dlm_mle_cache, mle);
|
|
ret = -EINVAL; /* need a better solution */
|
|
goto unlock;
|
|
}
|
|
res->state |= DLM_LOCK_RES_MIGRATING;
|
|
spin_unlock(&res->spinlock);
|
|
}
|
|
|
|
/* ignore status. only nonzero status would BUG. */
|
|
ret = dlm_add_migration_mle(dlm, res, mle, &oldmle,
|
|
name, namelen,
|
|
migrate->new_master,
|
|
migrate->master);
|
|
|
|
unlock:
|
|
spin_unlock(&dlm->master_lock);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
if (oldmle) {
|
|
/* master is known, detach if not already detached */
|
|
dlm_mle_detach_hb_events(dlm, oldmle);
|
|
dlm_put_mle(oldmle);
|
|
}
|
|
|
|
if (res)
|
|
dlm_lockres_put(res);
|
|
leave:
|
|
dlm_put(dlm);
|
|
return ret;
|
|
}
|
|
|
|
/* must be holding dlm->spinlock and dlm->master_lock
|
|
* when adding a migration mle, we can clear any other mles
|
|
* in the master list because we know with certainty that
|
|
* the master is "master". so we remove any old mle from
|
|
* the list after setting it's master field, and then add
|
|
* the new migration mle. this way we can hold with the rule
|
|
* of having only one mle for a given lock name at all times. */
|
|
static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res,
|
|
struct dlm_master_list_entry *mle,
|
|
struct dlm_master_list_entry **oldmle,
|
|
const char *name, unsigned int namelen,
|
|
u8 new_master, u8 master)
|
|
{
|
|
int found;
|
|
int ret = 0;
|
|
|
|
*oldmle = NULL;
|
|
|
|
mlog_entry_void();
|
|
|
|
assert_spin_locked(&dlm->spinlock);
|
|
assert_spin_locked(&dlm->master_lock);
|
|
|
|
/* caller is responsible for any ref taken here on oldmle */
|
|
found = dlm_find_mle(dlm, oldmle, (char *)name, namelen);
|
|
if (found) {
|
|
struct dlm_master_list_entry *tmp = *oldmle;
|
|
spin_lock(&tmp->spinlock);
|
|
if (tmp->type == DLM_MLE_MIGRATION) {
|
|
if (master == dlm->node_num) {
|
|
/* ah another process raced me to it */
|
|
mlog(0, "tried to migrate %.*s, but some "
|
|
"process beat me to it\n",
|
|
namelen, name);
|
|
ret = -EEXIST;
|
|
} else {
|
|
/* bad. 2 NODES are trying to migrate! */
|
|
mlog(ML_ERROR, "migration error mle: "
|
|
"master=%u new_master=%u // request: "
|
|
"master=%u new_master=%u // "
|
|
"lockres=%.*s\n",
|
|
tmp->master, tmp->new_master,
|
|
master, new_master,
|
|
namelen, name);
|
|
BUG();
|
|
}
|
|
} else {
|
|
/* this is essentially what assert_master does */
|
|
tmp->master = master;
|
|
atomic_set(&tmp->woken, 1);
|
|
wake_up(&tmp->wq);
|
|
/* remove it from the list so that only one
|
|
* mle will be found */
|
|
list_del_init(&tmp->list);
|
|
/* this was obviously WRONG. mle is uninited here. should be tmp. */
|
|
__dlm_mle_detach_hb_events(dlm, tmp);
|
|
ret = DLM_MIGRATE_RESPONSE_MASTERY_REF;
|
|
mlog(0, "%s:%.*s: master=%u, newmaster=%u, "
|
|
"telling master to get ref for cleared out mle "
|
|
"during migration\n", dlm->name, namelen, name,
|
|
master, new_master);
|
|
}
|
|
spin_unlock(&tmp->spinlock);
|
|
}
|
|
|
|
/* now add a migration mle to the tail of the list */
|
|
dlm_init_mle(mle, DLM_MLE_MIGRATION, dlm, res, name, namelen);
|
|
mle->new_master = new_master;
|
|
/* the new master will be sending an assert master for this.
|
|
* at that point we will get the refmap reference */
|
|
mle->master = master;
|
|
/* do this for consistency with other mle types */
|
|
set_bit(new_master, mle->maybe_map);
|
|
list_add(&mle->list, &dlm->master_list);
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node)
|
|
{
|
|
struct list_head *iter, *iter2;
|
|
struct dlm_master_list_entry *mle;
|
|
struct dlm_lock_resource *res;
|
|
unsigned int hash;
|
|
|
|
mlog_entry("dlm=%s, dead node=%u\n", dlm->name, dead_node);
|
|
top:
|
|
assert_spin_locked(&dlm->spinlock);
|
|
|
|
/* clean the master list */
|
|
spin_lock(&dlm->master_lock);
|
|
list_for_each_safe(iter, iter2, &dlm->master_list) {
|
|
mle = list_entry(iter, struct dlm_master_list_entry, list);
|
|
|
|
BUG_ON(mle->type != DLM_MLE_BLOCK &&
|
|
mle->type != DLM_MLE_MASTER &&
|
|
mle->type != DLM_MLE_MIGRATION);
|
|
|
|
/* MASTER mles are initiated locally. the waiting
|
|
* process will notice the node map change
|
|
* shortly. let that happen as normal. */
|
|
if (mle->type == DLM_MLE_MASTER)
|
|
continue;
|
|
|
|
|
|
/* BLOCK mles are initiated by other nodes.
|
|
* need to clean up if the dead node would have
|
|
* been the master. */
|
|
if (mle->type == DLM_MLE_BLOCK) {
|
|
int bit;
|
|
|
|
spin_lock(&mle->spinlock);
|
|
bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
|
|
if (bit != dead_node) {
|
|
mlog(0, "mle found, but dead node %u would "
|
|
"not have been master\n", dead_node);
|
|
spin_unlock(&mle->spinlock);
|
|
} else {
|
|
/* must drop the refcount by one since the
|
|
* assert_master will never arrive. this
|
|
* may result in the mle being unlinked and
|
|
* freed, but there may still be a process
|
|
* waiting in the dlmlock path which is fine. */
|
|
mlog(0, "node %u was expected master\n",
|
|
dead_node);
|
|
atomic_set(&mle->woken, 1);
|
|
spin_unlock(&mle->spinlock);
|
|
wake_up(&mle->wq);
|
|
/* do not need events any longer, so detach
|
|
* from heartbeat */
|
|
__dlm_mle_detach_hb_events(dlm, mle);
|
|
__dlm_put_mle(mle);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/* everything else is a MIGRATION mle */
|
|
|
|
/* the rule for MIGRATION mles is that the master
|
|
* becomes UNKNOWN if *either* the original or
|
|
* the new master dies. all UNKNOWN lockreses
|
|
* are sent to whichever node becomes the recovery
|
|
* master. the new master is responsible for
|
|
* determining if there is still a master for
|
|
* this lockres, or if he needs to take over
|
|
* mastery. either way, this node should expect
|
|
* another message to resolve this. */
|
|
if (mle->master != dead_node &&
|
|
mle->new_master != dead_node)
|
|
continue;
|
|
|
|
/* if we have reached this point, this mle needs to
|
|
* be removed from the list and freed. */
|
|
|
|
/* remove from the list early. NOTE: unlinking
|
|
* list_head while in list_for_each_safe */
|
|
__dlm_mle_detach_hb_events(dlm, mle);
|
|
spin_lock(&mle->spinlock);
|
|
list_del_init(&mle->list);
|
|
atomic_set(&mle->woken, 1);
|
|
spin_unlock(&mle->spinlock);
|
|
wake_up(&mle->wq);
|
|
|
|
mlog(0, "%s: node %u died during migration from "
|
|
"%u to %u!\n", dlm->name, dead_node,
|
|
mle->master, mle->new_master);
|
|
/* if there is a lockres associated with this
|
|
* mle, find it and set its owner to UNKNOWN */
|
|
hash = dlm_lockid_hash(mle->u.name.name, mle->u.name.len);
|
|
res = __dlm_lookup_lockres(dlm, mle->u.name.name,
|
|
mle->u.name.len, hash);
|
|
if (res) {
|
|
/* unfortunately if we hit this rare case, our
|
|
* lock ordering is messed. we need to drop
|
|
* the master lock so that we can take the
|
|
* lockres lock, meaning that we will have to
|
|
* restart from the head of list. */
|
|
spin_unlock(&dlm->master_lock);
|
|
|
|
/* move lockres onto recovery list */
|
|
spin_lock(&res->spinlock);
|
|
dlm_set_lockres_owner(dlm, res,
|
|
DLM_LOCK_RES_OWNER_UNKNOWN);
|
|
dlm_move_lockres_to_recovery_list(dlm, res);
|
|
spin_unlock(&res->spinlock);
|
|
dlm_lockres_put(res);
|
|
|
|
/* about to get rid of mle, detach from heartbeat */
|
|
__dlm_mle_detach_hb_events(dlm, mle);
|
|
|
|
/* dump the mle */
|
|
spin_lock(&dlm->master_lock);
|
|
__dlm_put_mle(mle);
|
|
spin_unlock(&dlm->master_lock);
|
|
|
|
/* restart */
|
|
goto top;
|
|
}
|
|
|
|
/* this may be the last reference */
|
|
__dlm_put_mle(mle);
|
|
}
|
|
spin_unlock(&dlm->master_lock);
|
|
}
|
|
|
|
|
|
int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
|
|
u8 old_master)
|
|
{
|
|
struct dlm_node_iter iter;
|
|
int ret = 0;
|
|
|
|
spin_lock(&dlm->spinlock);
|
|
dlm_node_iter_init(dlm->domain_map, &iter);
|
|
clear_bit(old_master, iter.node_map);
|
|
clear_bit(dlm->node_num, iter.node_map);
|
|
spin_unlock(&dlm->spinlock);
|
|
|
|
/* ownership of the lockres is changing. account for the
|
|
* mastery reference here since old_master will briefly have
|
|
* a reference after the migration completes */
|
|
spin_lock(&res->spinlock);
|
|
dlm_lockres_set_refmap_bit(old_master, res);
|
|
spin_unlock(&res->spinlock);
|
|
|
|
mlog(0, "now time to do a migrate request to other nodes\n");
|
|
ret = dlm_do_migrate_request(dlm, res, old_master,
|
|
dlm->node_num, &iter);
|
|
if (ret < 0) {
|
|
mlog_errno(ret);
|
|
goto leave;
|
|
}
|
|
|
|
mlog(0, "doing assert master of %.*s to all except the original node\n",
|
|
res->lockname.len, res->lockname.name);
|
|
/* this call now finishes out the nodemap
|
|
* even if one or more nodes die */
|
|
ret = dlm_do_assert_master(dlm, res, iter.node_map,
|
|
DLM_ASSERT_MASTER_FINISH_MIGRATION);
|
|
if (ret < 0) {
|
|
/* no longer need to retry. all living nodes contacted. */
|
|
mlog_errno(ret);
|
|
ret = 0;
|
|
}
|
|
|
|
memset(iter.node_map, 0, sizeof(iter.node_map));
|
|
set_bit(old_master, iter.node_map);
|
|
mlog(0, "doing assert master of %.*s back to %u\n",
|
|
res->lockname.len, res->lockname.name, old_master);
|
|
ret = dlm_do_assert_master(dlm, res, iter.node_map,
|
|
DLM_ASSERT_MASTER_FINISH_MIGRATION);
|
|
if (ret < 0) {
|
|
mlog(0, "assert master to original master failed "
|
|
"with %d.\n", ret);
|
|
/* the only nonzero status here would be because of
|
|
* a dead original node. we're done. */
|
|
ret = 0;
|
|
}
|
|
|
|
/* all done, set the owner, clear the flag */
|
|
spin_lock(&res->spinlock);
|
|
dlm_set_lockres_owner(dlm, res, dlm->node_num);
|
|
res->state &= ~DLM_LOCK_RES_MIGRATING;
|
|
spin_unlock(&res->spinlock);
|
|
/* re-dirty it on the new master */
|
|
dlm_kick_thread(dlm, res);
|
|
wake_up(&res->wq);
|
|
leave:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* LOCKRES AST REFCOUNT
|
|
* this is integral to migration
|
|
*/
|
|
|
|
/* for future intent to call an ast, reserve one ahead of time.
|
|
* this should be called only after waiting on the lockres
|
|
* with dlm_wait_on_lockres, and while still holding the
|
|
* spinlock after the call. */
|
|
void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res)
|
|
{
|
|
assert_spin_locked(&res->spinlock);
|
|
if (res->state & DLM_LOCK_RES_MIGRATING) {
|
|
__dlm_print_one_lock_resource(res);
|
|
}
|
|
BUG_ON(res->state & DLM_LOCK_RES_MIGRATING);
|
|
|
|
atomic_inc(&res->asts_reserved);
|
|
}
|
|
|
|
/*
|
|
* used to drop the reserved ast, either because it went unused,
|
|
* or because the ast/bast was actually called.
|
|
*
|
|
* also, if there is a pending migration on this lockres,
|
|
* and this was the last pending ast on the lockres,
|
|
* atomically set the MIGRATING flag before we drop the lock.
|
|
* this is how we ensure that migration can proceed with no
|
|
* asts in progress. note that it is ok if the state of the
|
|
* queues is such that a lock should be granted in the future
|
|
* or that a bast should be fired, because the new master will
|
|
* shuffle the lists on this lockres as soon as it is migrated.
|
|
*/
|
|
void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
|
|
struct dlm_lock_resource *res)
|
|
{
|
|
if (!atomic_dec_and_lock(&res->asts_reserved, &res->spinlock))
|
|
return;
|
|
|
|
if (!res->migration_pending) {
|
|
spin_unlock(&res->spinlock);
|
|
return;
|
|
}
|
|
|
|
BUG_ON(res->state & DLM_LOCK_RES_MIGRATING);
|
|
res->migration_pending = 0;
|
|
res->state |= DLM_LOCK_RES_MIGRATING;
|
|
spin_unlock(&res->spinlock);
|
|
wake_up(&res->wq);
|
|
wake_up(&dlm->migration_wq);
|
|
}
|