linux-sg2042/fs/dlm/member.c

391 lines
9.0 KiB
C

/******************************************************************************
*******************************************************************************
**
** Copyright (C) 2005-2009 Red Hat, Inc. All rights reserved.
**
** This copyrighted material is made available to anyone wishing to use,
** modify, copy, or redistribute it subject to the terms and conditions
** of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/
#include "dlm_internal.h"
#include "lockspace.h"
#include "member.h"
#include "recoverd.h"
#include "recover.h"
#include "rcom.h"
#include "config.h"
#include "lowcomms.h"
static void add_ordered_member(struct dlm_ls *ls, struct dlm_member *new)
{
struct dlm_member *memb = NULL;
struct list_head *tmp;
struct list_head *newlist = &new->list;
struct list_head *head = &ls->ls_nodes;
list_for_each(tmp, head) {
memb = list_entry(tmp, struct dlm_member, list);
if (new->nodeid < memb->nodeid)
break;
}
if (!memb)
list_add_tail(newlist, head);
else {
/* FIXME: can use list macro here */
newlist->prev = tmp->prev;
newlist->next = tmp;
tmp->prev->next = newlist;
tmp->prev = newlist;
}
}
static int dlm_add_member(struct dlm_ls *ls, int nodeid)
{
struct dlm_member *memb;
int w, error;
memb = kzalloc(sizeof(struct dlm_member), GFP_NOFS);
if (!memb)
return -ENOMEM;
w = dlm_node_weight(ls->ls_name, nodeid);
if (w < 0) {
kfree(memb);
return w;
}
error = dlm_lowcomms_connect_node(nodeid);
if (error < 0) {
kfree(memb);
return error;
}
memb->nodeid = nodeid;
memb->weight = w;
add_ordered_member(ls, memb);
ls->ls_num_nodes++;
return 0;
}
static void dlm_remove_member(struct dlm_ls *ls, struct dlm_member *memb)
{
list_move(&memb->list, &ls->ls_nodes_gone);
ls->ls_num_nodes--;
}
int dlm_is_member(struct dlm_ls *ls, int nodeid)
{
struct dlm_member *memb;
list_for_each_entry(memb, &ls->ls_nodes, list) {
if (memb->nodeid == nodeid)
return 1;
}
return 0;
}
int dlm_is_removed(struct dlm_ls *ls, int nodeid)
{
struct dlm_member *memb;
list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
if (memb->nodeid == nodeid)
return 1;
}
return 0;
}
static void clear_memb_list(struct list_head *head)
{
struct dlm_member *memb;
while (!list_empty(head)) {
memb = list_entry(head->next, struct dlm_member, list);
list_del(&memb->list);
kfree(memb);
}
}
void dlm_clear_members(struct dlm_ls *ls)
{
clear_memb_list(&ls->ls_nodes);
ls->ls_num_nodes = 0;
}
void dlm_clear_members_gone(struct dlm_ls *ls)
{
clear_memb_list(&ls->ls_nodes_gone);
}
static void make_member_array(struct dlm_ls *ls)
{
struct dlm_member *memb;
int i, w, x = 0, total = 0, all_zero = 0, *array;
kfree(ls->ls_node_array);
ls->ls_node_array = NULL;
list_for_each_entry(memb, &ls->ls_nodes, list) {
if (memb->weight)
total += memb->weight;
}
/* all nodes revert to weight of 1 if all have weight 0 */
if (!total) {
total = ls->ls_num_nodes;
all_zero = 1;
}
ls->ls_total_weight = total;
array = kmalloc(sizeof(int) * total, GFP_NOFS);
if (!array)
return;
list_for_each_entry(memb, &ls->ls_nodes, list) {
if (!all_zero && !memb->weight)
continue;
if (all_zero)
w = 1;
else
w = memb->weight;
DLM_ASSERT(x < total, printk("total %d x %d\n", total, x););
for (i = 0; i < w; i++)
array[x++] = memb->nodeid;
}
ls->ls_node_array = array;
}
/* send a status request to all members just to establish comms connections */
static int ping_members(struct dlm_ls *ls)
{
struct dlm_member *memb;
int error = 0;
list_for_each_entry(memb, &ls->ls_nodes, list) {
error = dlm_recovery_stopped(ls);
if (error)
break;
error = dlm_rcom_status(ls, memb->nodeid);
if (error)
break;
}
if (error)
log_debug(ls, "ping_members aborted %d last nodeid %d",
error, ls->ls_recover_nodeid);
return error;
}
int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv, int *neg_out)
{
struct dlm_member *memb, *safe;
int i, error, found, pos = 0, neg = 0, low = -1;
/* previously removed members that we've not finished removing need to
count as a negative change so the "neg" recovery steps will happen */
list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
log_debug(ls, "prev removed member %d", memb->nodeid);
neg++;
}
/* move departed members from ls_nodes to ls_nodes_gone */
list_for_each_entry_safe(memb, safe, &ls->ls_nodes, list) {
found = 0;
for (i = 0; i < rv->node_count; i++) {
if (memb->nodeid == rv->nodeids[i]) {
found = 1;
break;
}
}
if (!found) {
neg++;
dlm_remove_member(ls, memb);
log_debug(ls, "remove member %d", memb->nodeid);
}
}
/* Add an entry to ls_nodes_gone for members that were removed and
then added again, so that previous state for these nodes will be
cleared during recovery. */
for (i = 0; i < rv->new_count; i++) {
if (!dlm_is_member(ls, rv->new[i]))
continue;
log_debug(ls, "new nodeid %d is a re-added member", rv->new[i]);
memb = kzalloc(sizeof(struct dlm_member), GFP_NOFS);
if (!memb)
return -ENOMEM;
memb->nodeid = rv->new[i];
list_add_tail(&memb->list, &ls->ls_nodes_gone);
neg++;
}
/* add new members to ls_nodes */
for (i = 0; i < rv->node_count; i++) {
if (dlm_is_member(ls, rv->nodeids[i]))
continue;
dlm_add_member(ls, rv->nodeids[i]);
pos++;
log_debug(ls, "add member %d", rv->nodeids[i]);
}
list_for_each_entry(memb, &ls->ls_nodes, list) {
if (low == -1 || memb->nodeid < low)
low = memb->nodeid;
}
ls->ls_low_nodeid = low;
make_member_array(ls);
dlm_set_recover_status(ls, DLM_RS_NODES);
*neg_out = neg;
error = ping_members(ls);
if (!error || error == -EPROTO) {
/* new_lockspace() may be waiting to know if the config
is good or bad */
ls->ls_members_result = error;
complete(&ls->ls_members_done);
}
if (error)
goto out;
error = dlm_recover_members_wait(ls);
out:
log_debug(ls, "total members %d error %d", ls->ls_num_nodes, error);
return error;
}
/* Userspace guarantees that dlm_ls_stop() has completed on all nodes before
dlm_ls_start() is called on any of them to start the new recovery. */
int dlm_ls_stop(struct dlm_ls *ls)
{
int new;
/*
* Prevent dlm_recv from being in the middle of something when we do
* the stop. This includes ensuring dlm_recv isn't processing a
* recovery message (rcom), while dlm_recoverd is aborting and
* resetting things from an in-progress recovery. i.e. we want
* dlm_recoverd to abort its recovery without worrying about dlm_recv
* processing an rcom at the same time. Stopping dlm_recv also makes
* it easy for dlm_receive_message() to check locking stopped and add a
* message to the requestqueue without races.
*/
down_write(&ls->ls_recv_active);
/*
* Abort any recovery that's in progress (see RECOVERY_STOP,
* dlm_recovery_stopped()) and tell any other threads running in the
* dlm to quit any processing (see RUNNING, dlm_locking_stopped()).
*/
spin_lock(&ls->ls_recover_lock);
set_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
new = test_and_clear_bit(LSFL_RUNNING, &ls->ls_flags);
ls->ls_recover_seq++;
spin_unlock(&ls->ls_recover_lock);
/*
* Let dlm_recv run again, now any normal messages will be saved on the
* requestqueue for later.
*/
up_write(&ls->ls_recv_active);
/*
* This in_recovery lock does two things:
* 1) Keeps this function from returning until all threads are out
* of locking routines and locking is truely stopped.
* 2) Keeps any new requests from being processed until it's unlocked
* when recovery is complete.
*/
if (new)
down_write(&ls->ls_in_recovery);
/*
* The recoverd suspend/resume makes sure that dlm_recoverd (if
* running) has noticed RECOVERY_STOP above and quit processing the
* previous recovery.
*/
dlm_recoverd_suspend(ls);
ls->ls_recover_status = 0;
dlm_recoverd_resume(ls);
if (!ls->ls_recover_begin)
ls->ls_recover_begin = jiffies;
return 0;
}
int dlm_ls_start(struct dlm_ls *ls)
{
struct dlm_recover *rv = NULL, *rv_old;
int *ids = NULL, *new = NULL;
int error, ids_count = 0, new_count = 0;
rv = kzalloc(sizeof(struct dlm_recover), GFP_NOFS);
if (!rv)
return -ENOMEM;
error = dlm_nodeid_list(ls->ls_name, &ids, &ids_count,
&new, &new_count);
if (error < 0)
goto fail;
spin_lock(&ls->ls_recover_lock);
/* the lockspace needs to be stopped before it can be started */
if (!dlm_locking_stopped(ls)) {
spin_unlock(&ls->ls_recover_lock);
log_error(ls, "start ignored: lockspace running");
error = -EINVAL;
goto fail;
}
rv->nodeids = ids;
rv->node_count = ids_count;
rv->new = new;
rv->new_count = new_count;
rv->seq = ++ls->ls_recover_seq;
rv_old = ls->ls_recover_args;
ls->ls_recover_args = rv;
spin_unlock(&ls->ls_recover_lock);
if (rv_old) {
log_error(ls, "unused recovery %llx %d",
(unsigned long long)rv_old->seq, rv_old->node_count);
kfree(rv_old->nodeids);
kfree(rv_old->new);
kfree(rv_old);
}
dlm_recoverd_kick(ls);
return 0;
fail:
kfree(rv);
kfree(ids);
kfree(new);
return error;
}