Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm (13dd7f87) · Commits · e / devices / android_kernel_fairphone_FP3

fs/dlm/config.c

+53 −24

Original line number	Diff line number	Diff line
		@@ -14,6 +14,9 @@
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/configfs.h>
		#include <linux/in.h>
		#include <linux/in6.h>
		#include <net/ipv6.h>
		#include <net/sock.h>

		#include "config.h"
		@@ -377,24 +380,24 @@ static struct config_item_type node_type = {
		.ct_owner = THIS_MODULE,
		};

		static struct dlm_cluster to_cluster(struct config_item i)
		static struct dlm_cluster config_item_to_cluster(struct config_item i)
		{
		return i ? container_of(to_config_group(i), struct dlm_cluster, group) :
		NULL;
		}

		static struct dlm_space to_space(struct config_item i)
		static struct dlm_space config_item_to_space(struct config_item i)
		{
		return i ? container_of(to_config_group(i), struct dlm_space, group) :
		NULL;
		}

		static struct dlm_comm to_comm(struct config_item i)
		static struct dlm_comm config_item_to_comm(struct config_item i)
		{
		return i ? container_of(i, struct dlm_comm, item) : NULL;
		}

		static struct dlm_node to_node(struct config_item i)
		static struct dlm_node config_item_to_node(struct config_item i)
		{
		return i ? container_of(i, struct dlm_node, item) : NULL;
		}
		@@ -450,7 +453,7 @@ static struct config_group make_cluster(struct config_group g,

		static void drop_cluster(struct config_group g, struct config_item i)
		{
		struct dlm_cluster *cl = to_cluster(i);
		struct dlm_cluster *cl = config_item_to_cluster(i);
		struct config_item *tmp;
		int j;

		@@ -468,7 +471,7 @@ static void drop_cluster(struct config_group g, struct config_item i)

		static void release_cluster(struct config_item *i)
		{
		struct dlm_cluster *cl = to_cluster(i);
		struct dlm_cluster *cl = config_item_to_cluster(i);
		kfree(cl->group.default_groups);
		kfree(cl);
		}
		@@ -507,7 +510,7 @@ static struct config_group make_space(struct config_group g, const char *name)

		static void drop_space(struct config_group g, struct config_item i)
		{
		struct dlm_space *sp = to_space(i);
		struct dlm_space *sp = config_item_to_space(i);
		struct config_item *tmp;
		int j;

		@@ -524,7 +527,7 @@ static void drop_space(struct config_group g, struct config_item i)

		static void release_space(struct config_item *i)
		{
		struct dlm_space *sp = to_space(i);
		struct dlm_space *sp = config_item_to_space(i);
		kfree(sp->group.default_groups);
		kfree(sp);
		}
		@@ -546,7 +549,7 @@ static struct config_item make_comm(struct config_group g, const char *name)

		static void drop_comm(struct config_group g, struct config_item i)
		{
		struct dlm_comm *cm = to_comm(i);
		struct dlm_comm *cm = config_item_to_comm(i);
		if (local_comm == cm)
		local_comm = NULL;
		dlm_lowcomms_close(cm->nodeid);
		@@ -557,13 +560,13 @@ static void drop_comm(struct config_group g, struct config_item i)

		static void release_comm(struct config_item *i)
		{
		struct dlm_comm *cm = to_comm(i);
		struct dlm_comm *cm = config_item_to_comm(i);
		kfree(cm);
		}

		static struct config_item make_node(struct config_group g, const char *name)
		{
		struct dlm_space *sp = to_space(g->cg_item.ci_parent);
		struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
		struct dlm_node *nd;

		nd = kzalloc(sizeof(struct dlm_node), GFP_KERNEL);
		@@ -585,8 +588,8 @@ static struct config_item make_node(struct config_group g, const char *name)

		static void drop_node(struct config_group g, struct config_item i)
		{
		struct dlm_space *sp = to_space(g->cg_item.ci_parent);
		struct dlm_node *nd = to_node(i);
		struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
		struct dlm_node *nd = config_item_to_node(i);

		mutex_lock(&sp->members_lock);
		list_del(&nd->list);
		@@ -598,7 +601,7 @@ static void drop_node(struct config_group g, struct config_item i)

		static void release_node(struct config_item *i)
		{
		struct dlm_node *nd = to_node(i);
		struct dlm_node *nd = config_item_to_node(i);
		kfree(nd);
		}

		@@ -632,7 +635,7 @@ void dlm_config_exit(void)
		static ssize_t show_cluster(struct config_item i, struct configfs_attribute a,
		char *buf)
		{
		struct dlm_cluster *cl = to_cluster(i);
		struct dlm_cluster *cl = config_item_to_cluster(i);
		struct cluster_attribute *cla =
		container_of(a, struct cluster_attribute, attr);
		return cla->show ? cla->show(cl, buf) : 0;
		@@ -642,7 +645,7 @@ static ssize_t store_cluster(struct config_item *i,
		struct configfs_attribute *a,
		const char *buf, size_t len)
		{
		struct dlm_cluster *cl = to_cluster(i);
		struct dlm_cluster *cl = config_item_to_cluster(i);
		struct cluster_attribute *cla =
		container_of(a, struct cluster_attribute, attr);
		return cla->store ? cla->store(cl, buf, len) : -EINVAL;
		@@ -651,7 +654,7 @@ static ssize_t store_cluster(struct config_item *i,
		static ssize_t show_comm(struct config_item i, struct configfs_attribute a,
		char *buf)
		{
		struct dlm_comm *cm = to_comm(i);
		struct dlm_comm *cm = config_item_to_comm(i);
		struct comm_attribute *cma =
		container_of(a, struct comm_attribute, attr);
		return cma->show ? cma->show(cm, buf) : 0;
		@@ -660,7 +663,7 @@ static ssize_t show_comm(struct config_item i, struct configfs_attribute a,
		static ssize_t store_comm(struct config_item i, struct configfs_attribute a,
		const char *buf, size_t len)
		{
		struct dlm_comm *cm = to_comm(i);
		struct dlm_comm *cm = config_item_to_comm(i);
		struct comm_attribute *cma =
		container_of(a, struct comm_attribute, attr);
		return cma->store ? cma->store(cm, buf, len) : -EINVAL;
		@@ -714,7 +717,7 @@ static ssize_t comm_addr_write(struct dlm_comm cm, const char buf, size_t len)
		static ssize_t show_node(struct config_item i, struct configfs_attribute a,
		char *buf)
		{
		struct dlm_node *nd = to_node(i);
		struct dlm_node *nd = config_item_to_node(i);
		struct node_attribute *nda =
		container_of(a, struct node_attribute, attr);
		return nda->show ? nda->show(nd, buf) : 0;
		@@ -723,7 +726,7 @@ static ssize_t show_node(struct config_item i, struct configfs_attribute a,
		static ssize_t store_node(struct config_item i, struct configfs_attribute a,
		const char *buf, size_t len)
		{
		struct dlm_node *nd = to_node(i);
		struct dlm_node *nd = config_item_to_node(i);
		struct node_attribute *nda =
		container_of(a, struct node_attribute, attr);
		return nda->store ? nda->store(nd, buf, len) : -EINVAL;
		@@ -768,7 +771,7 @@ static struct dlm_space get_space(char name)
		i = config_group_find_item(space_list, name);
		mutex_unlock(&space_list->cg_subsys->su_mutex);

		return to_space(i);
		return config_item_to_space(i);
		}

		static void put_space(struct dlm_space *sp)
		@@ -776,6 +779,33 @@ static void put_space(struct dlm_space *sp)
		config_item_put(&sp->group.cg_item);
		}

		static int addr_compare(struct sockaddr_storage x, struct sockaddr_storage y)
		{
		switch (x->ss_family) {
		case AF_INET: {
		struct sockaddr_in sinx = (struct sockaddr_in )x;
		struct sockaddr_in siny = (struct sockaddr_in )y;
		if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
		return 0;
		if (sinx->sin_port != siny->sin_port)
		return 0;
		break;
		}
		case AF_INET6: {
		struct sockaddr_in6 sinx = (struct sockaddr_in6 )x;
		struct sockaddr_in6 siny = (struct sockaddr_in6 )y;
		if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
		return 0;
		if (sinx->sin6_port != siny->sin6_port)
		return 0;
		break;
		}
		default:
		return 0;
		}
		return 1;
		}

		static struct dlm_comm get_comm(int nodeid, struct sockaddr_storage addr)
		{
		struct config_item *i;
		@@ -788,7 +818,7 @@ static struct dlm_comm get_comm(int nodeid, struct sockaddr_storage addr)
		mutex_lock(&clusters_root.subsys.su_mutex);

		list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
		cm = to_comm(i);
		cm = config_item_to_comm(i);

		if (nodeid) {
		if (cm->nodeid != nodeid)
		@@ -797,8 +827,7 @@ static struct dlm_comm get_comm(int nodeid, struct sockaddr_storage addr)
		config_item_get(i);
		break;
		} else {
		if (!cm->addr_count \|\|
		memcmp(cm->addr[0], addr, sizeof(*addr)))
		if (!cm->addr_count \|\| !addr_compare(cm->addr[0], addr))
		continue;
		found = 1;
		config_item_get(i);

fs/dlm/dlm_internal.h

+5 −2

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		*******************************************************************************
		**
		** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
		** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
		** Copyright (C) 2004-2008 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
		@@ -441,8 +441,11 @@ struct dlm_ls {
		uint32_t ls_global_id; /* global unique lockspace ID */
		uint32_t ls_exflags;
		int ls_lvblen;
		int ls_count; /* reference count */
		int ls_count; /* refcount of processes in
		the dlm using this ls */
		int ls_create_count; /* create/release refcount */
		unsigned long ls_flags; /* LSFL_ */
		unsigned long ls_scan_time;
		struct kobject ls_kobj;

		struct dlm_rsbtable *ls_rsbtbl;

fs/dlm/lockspace.c

+118 −40

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		*******************************************************************************
		**
		** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
		** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
		** Copyright (C) 2004-2008 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
		@@ -23,6 +23,7 @@
		#include "lock.h"
		#include "recover.h"
		#include "requestqueue.h"
		#include "user.h"

		static int ls_count;
		static struct mutex ls_lock;
		@@ -211,19 +212,41 @@ void dlm_lockspace_exit(void)
		kset_unregister(dlm_kset);
		}

		static struct dlm_ls *find_ls_to_scan(void)
		{
		struct dlm_ls *ls;

		spin_lock(&lslist_lock);
		list_for_each_entry(ls, &lslist, ls_list) {
		if (time_after_eq(jiffies, ls->ls_scan_time +
		dlm_config.ci_scan_secs * HZ)) {
		spin_unlock(&lslist_lock);
		return ls;
		}
		}
		spin_unlock(&lslist_lock);
		return NULL;
		}

		static int dlm_scand(void *data)
		{
		struct dlm_ls *ls;
		int timeout_jiffies = dlm_config.ci_scan_secs * HZ;

		while (!kthread_should_stop()) {
		list_for_each_entry(ls, &lslist, ls_list) {
		ls = find_ls_to_scan();
		if (ls) {
		if (dlm_lock_recovery_try(ls)) {
		ls->ls_scan_time = jiffies;
		dlm_scan_rsbs(ls);
		dlm_scan_timeout(ls);
		dlm_unlock_recovery(ls);
		} else {
		ls->ls_scan_time += HZ;
		}
		} else {
		schedule_timeout_interruptible(timeout_jiffies);
		}
		schedule_timeout_interruptible(dlm_config.ci_scan_secs * HZ);
		}
		return 0;
		}
		@@ -246,23 +269,6 @@ static void dlm_scand_stop(void)
		kthread_stop(scand_task);
		}

		static struct dlm_ls dlm_find_lockspace_name(char name, int namelen)
		{
		struct dlm_ls *ls;

		spin_lock(&lslist_lock);

		list_for_each_entry(ls, &lslist, ls_list) {
		if (ls->ls_namelen == namelen &&
		memcmp(ls->ls_name, name, namelen) == 0)
		goto out;
		}
		ls = NULL;
		out:
		spin_unlock(&lslist_lock);
		return ls;
		}

		struct dlm_ls *dlm_find_lockspace_global(uint32_t id)
		{
		struct dlm_ls *ls;
		@@ -327,6 +333,7 @@ static void remove_lockspace(struct dlm_ls *ls)
		for (;;) {
		spin_lock(&lslist_lock);
		if (ls->ls_count == 0) {
		WARN_ON(ls->ls_create_count != 0);
		list_del(&ls->ls_list);
		spin_unlock(&lslist_lock);
		return;
		@@ -381,7 +388,7 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		uint32_t flags, int lvblen)
		{
		struct dlm_ls *ls;
		int i, size, error = -ENOMEM;
		int i, size, error;
		int do_unreg = 0;

		if (namelen > DLM_LOCKSPACE_LEN)
		@@ -393,13 +400,38 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		if (!try_module_get(THIS_MODULE))
		return -EINVAL;

		ls = dlm_find_lockspace_name(name, namelen);
		if (ls) {
		*lockspace = ls;
		if (!dlm_user_daemon_available()) {
		module_put(THIS_MODULE);
		return -EEXIST;
		return -EUNATCH;
		}

		error = 0;

		spin_lock(&lslist_lock);
		list_for_each_entry(ls, &lslist, ls_list) {
		WARN_ON(ls->ls_create_count <= 0);
		if (ls->ls_namelen != namelen)
		continue;
		if (memcmp(ls->ls_name, name, namelen))
		continue;
		if (flags & DLM_LSFL_NEWEXCL) {
		error = -EEXIST;
		break;
		}
		ls->ls_create_count++;
		module_put(THIS_MODULE);
		error = 1; /* not an error, return 0 */
		break;
		}
		spin_unlock(&lslist_lock);

		if (error < 0)
		goto out;
		if (error)
		goto ret_zero;

		error = -ENOMEM;

		ls = kzalloc(sizeof(struct dlm_ls) + namelen, GFP_KERNEL);
		if (!ls)
		goto out;
		@@ -408,6 +440,7 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		ls->ls_lvblen = lvblen;
		ls->ls_count = 0;
		ls->ls_flags = 0;
		ls->ls_scan_time = jiffies;

		if (flags & DLM_LSFL_TIMEWARN)
		set_bit(LSFL_TIMEWARN, &ls->ls_flags);
		@@ -418,8 +451,9 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		ls->ls_allocation = GFP_KERNEL;

		/* ls_exflags are forced to match among nodes, and we don't
		need to require all nodes to have TIMEWARN or FS set */
		ls->ls_exflags = (flags & ~(DLM_LSFL_TIMEWARN \| DLM_LSFL_FS));
		need to require all nodes to have some flags set */
		ls->ls_exflags = (flags & ~(DLM_LSFL_TIMEWARN \| DLM_LSFL_FS \|
		DLM_LSFL_NEWEXCL));

		size = dlm_config.ci_rsbtbl_size;
		ls->ls_rsbtbl_size = size;
		@@ -510,6 +544,7 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		down_write(&ls->ls_in_recovery);

		spin_lock(&lslist_lock);
		ls->ls_create_count = 1;
		list_add(&ls->ls_list, &lslist);
		spin_unlock(&lslist_lock);

		@@ -548,7 +583,7 @@ static int new_lockspace(char name, int namelen, void *lockspace,
		dlm_create_debug_file(ls);

		log_debug(ls, "join complete");

		ret_zero:
		*lockspace = ls;
		return 0;

		@@ -635,13 +670,34 @@ static int release_lockspace(struct dlm_ls *ls, int force)
		struct dlm_lkb *lkb;
		struct dlm_rsb *rsb;
		struct list_head *head;
		int i;
		int busy = lockspace_busy(ls);
		int i, busy, rv;

		busy = lockspace_busy(ls);

		spin_lock(&lslist_lock);
		if (ls->ls_create_count == 1) {
		if (busy > force)
		return -EBUSY;
		rv = -EBUSY;
		else {
		/* remove_lockspace takes ls off lslist */
		ls->ls_create_count = 0;
		rv = 0;
		}
		} else if (ls->ls_create_count > 1) {
		rv = --ls->ls_create_count;
		} else {
		rv = -EINVAL;
		}
		spin_unlock(&lslist_lock);

		if (force < 3)
		if (rv) {
		log_debug(ls, "release_lockspace no remove %d", rv);
		return rv;
		}

		dlm_device_deregister(ls);

		if (force < 3 && dlm_user_daemon_available())
		do_uevent(ls, 0);

		dlm_recoverd_stop(ls);
		@@ -720,15 +776,10 @@ static int release_lockspace(struct dlm_ls *ls, int force)
		dlm_clear_members(ls);
		dlm_clear_members_gone(ls);
		kfree(ls->ls_node_array);
		log_debug(ls, "release_lockspace final free");
		kobject_put(&ls->ls_kobj);
		/* The ls structure will be freed when the kobject is done with */

		mutex_lock(&ls_lock);
		ls_count--;
		if (!ls_count)
		threads_stop();
		mutex_unlock(&ls_lock);

		module_put(THIS_MODULE);
		return 0;
		}
		@@ -750,11 +801,38 @@ static int release_lockspace(struct dlm_ls *ls, int force)
		int dlm_release_lockspace(void *lockspace, int force)
		{
		struct dlm_ls *ls;
		int error;

		ls = dlm_find_lockspace_local(lockspace);
		if (!ls)
		return -EINVAL;
		dlm_put_lockspace(ls);
		return release_lockspace(ls, force);

		mutex_lock(&ls_lock);
		error = release_lockspace(ls, force);
		if (!error)
		ls_count--;
		else if (!ls_count)
		threads_stop();
		mutex_unlock(&ls_lock);

		return error;
		}

		void dlm_stop_lockspaces(void)
		{
		struct dlm_ls *ls;

		restart:
		spin_lock(&lslist_lock);
		list_for_each_entry(ls, &lslist, ls_list) {
		if (!test_bit(LSFL_RUNNING, &ls->ls_flags))
		continue;
		spin_unlock(&lslist_lock);
		log_error(ls, "no userland control daemon, stopping lockspace");
		dlm_ls_stop(ls);
		goto restart;
		}
		spin_unlock(&lslist_lock);
		}

fs/dlm/lockspace.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,7 @@ struct dlm_ls *dlm_find_lockspace_global(uint32_t id);
		struct dlm_ls dlm_find_lockspace_local(void id);
		struct dlm_ls *dlm_find_lockspace_device(int minor);
		void dlm_put_lockspace(struct dlm_ls *ls);
		void dlm_stop_lockspaces(void);

		#endif /* __LOCKSPACE_DOT_H__ */

fs/dlm/user.c

+94 −30

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved.
		* Copyright (C) 2006-2008 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
		@@ -15,7 +15,6 @@
		#include <linux/poll.h>
		#include <linux/signal.h>
		#include <linux/spinlock.h>
		#include <linux/smp_lock.h>
		#include <linux/dlm.h>
		#include <linux/dlm_device.h>

		@@ -27,6 +26,8 @@

		static const char name_prefix[] = "dlm";
		static const struct file_operations device_fops;
		static atomic_t dlm_monitor_opened;
		static int dlm_monitor_unused = 1;

		#ifdef CONFIG_COMPAT

		@@ -340,10 +341,15 @@ static int device_user_deadlock(struct dlm_user_proc *proc,
		return error;
		}

		static int create_misc_device(struct dlm_ls ls, char name)
		static int dlm_device_register(struct dlm_ls ls, char name)
		{
		int error, len;

		/* The device is already registered. This happens when the
		lockspace is created multiple times from userspace. */
		if (ls->ls_device.name)
		return 0;

		error = -ENOMEM;
		len = strlen(name) + strlen(name_prefix) + 2;
		ls->ls_device.name = kzalloc(len, GFP_KERNEL);
		@@ -363,6 +369,22 @@ static int create_misc_device(struct dlm_ls ls, char name)
		return error;
		}

		int dlm_device_deregister(struct dlm_ls *ls)
		{
		int error;

		/* The device is not registered. This happens when the lockspace
		was never used from userspace, or when device_create_lockspace()
		calls dlm_release_lockspace() after the register fails. */
		if (!ls->ls_device.name)
		return 0;

		error = misc_deregister(&ls->ls_device);
		if (!error)
		kfree(ls->ls_device.name);
		return error;
		}

		static int device_user_purge(struct dlm_user_proc *proc,
		struct dlm_purge_params *params)
		{
		@@ -397,7 +419,7 @@ static int device_create_lockspace(struct dlm_lspace_params *params)
		if (!ls)
		return -ENOENT;

		error = create_misc_device(ls, params->name);
		error = dlm_device_register(ls, params->name);
		dlm_put_lockspace(ls);

		if (error)
		@@ -421,31 +443,22 @@ static int device_remove_lockspace(struct dlm_lspace_params *params)
		if (!ls)
		return -ENOENT;

		/* Deregister the misc device first, so we don't have
		* a device that's not attached to a lockspace. If
		* dlm_release_lockspace fails then we can recreate it
		*/
		error = misc_deregister(&ls->ls_device);
		if (error) {
		dlm_put_lockspace(ls);
		goto out;
		}
		kfree(ls->ls_device.name);

		if (params->flags & DLM_USER_LSFLG_FORCEFREE)
		force = 2;

		lockspace = ls->ls_local_handle;
		dlm_put_lockspace(ls);

		/* dlm_release_lockspace waits for references to go to zero,
		so all processes will need to close their device for the ls
		before the release will procede */
		/* The final dlm_release_lockspace waits for references to go to
		zero, so all processes will need to close their device for the
		ls before the release will proceed. release also calls the
		device_deregister above. Converting a positive return value
		from release to zero means that userspace won't know when its
		release was the final one, but it shouldn't need to know. */

		dlm_put_lockspace(ls);
		error = dlm_release_lockspace(lockspace, force);
		if (error)
		create_misc_device(ls, ls->ls_name);
		out:
		if (error > 0)
		error = 0;
		return error;
		}

		@@ -623,17 +636,13 @@ static int device_open(struct inode inode, struct file file)
		struct dlm_user_proc *proc;
		struct dlm_ls *ls;

		lock_kernel();
		ls = dlm_find_lockspace_device(iminor(inode));
		if (!ls) {
		unlock_kernel();
		if (!ls)
		return -ENOENT;
		}

		proc = kzalloc(sizeof(struct dlm_user_proc), GFP_KERNEL);
		if (!proc) {
		dlm_put_lockspace(ls);
		unlock_kernel();
		return -ENOMEM;
		}

		@@ -645,7 +654,6 @@ static int device_open(struct inode inode, struct file file)
		spin_lock_init(&proc->locks_spin);
		init_waitqueue_head(&proc->wait);
		file->private_data = proc;
		unlock_kernel();

		return 0;
		}
		@@ -878,9 +886,28 @@ static unsigned int device_poll(struct file file, poll_table wait)
		return 0;
		}

		int dlm_user_daemon_available(void)
		{
		/* dlm_controld hasn't started (or, has started, but not
		properly populated configfs) */

		if (!dlm_our_nodeid())
		return 0;

		/* This is to deal with versions of dlm_controld that don't
		know about the monitor device. We assume that if the
		dlm_controld was started (above), but the monitor device
		was never opened, that it's an old version. dlm_controld
		should open the monitor device before populating configfs. */

		if (dlm_monitor_unused)
		return 1;

		return atomic_read(&dlm_monitor_opened) ? 1 : 0;
		}

		static int ctl_device_open(struct inode inode, struct file file)
		{
		cycle_kernel_lock();
		file->private_data = NULL;
		return 0;
		}
		@@ -890,6 +917,20 @@ static int ctl_device_close(struct inode inode, struct file file)
		return 0;
		}

		static int monitor_device_open(struct inode inode, struct file file)
		{
		atomic_inc(&dlm_monitor_opened);
		dlm_monitor_unused = 0;
		return 0;
		}

		static int monitor_device_close(struct inode inode, struct file file)
		{
		if (atomic_dec_and_test(&dlm_monitor_opened))
		dlm_stop_lockspaces();
		return 0;
		}

		static const struct file_operations device_fops = {
		.open = device_open,
		.release = device_close,
		@@ -913,19 +954,42 @@ static struct miscdevice ctl_device = {
		.minor = MISC_DYNAMIC_MINOR,
		};

		static const struct file_operations monitor_device_fops = {
		.open = monitor_device_open,
		.release = monitor_device_close,
		.owner = THIS_MODULE,
		};

		static struct miscdevice monitor_device = {
		.name = "dlm-monitor",
		.fops = &monitor_device_fops,
		.minor = MISC_DYNAMIC_MINOR,
		};

		int __init dlm_user_init(void)
		{
		int error;

		atomic_set(&dlm_monitor_opened, 0);

		error = misc_register(&ctl_device);
		if (error)
		if (error) {
		log_print("misc_register failed for control device");
		goto out;
		}

		error = misc_register(&monitor_device);
		if (error) {
		log_print("misc_register failed for monitor device");
		misc_deregister(&ctl_device);
		}
		out:
		return error;
		}

		void dlm_user_exit(void)
		{
		misc_deregister(&ctl_device);
		misc_deregister(&monitor_device);
		}