linux/fs/dlm/config.c
David Teigland 36b71a8bfb dlm: fix deadlock between dlm_send and dlm_controld
A deadlock sometimes occurs between dlm_controld closing
a lowcomms connection through configfs and dlm_send looking
up the address for a new connection in configfs.

dlm_controld does a configfs rmdir which calls
dlm_lowcomms_close which waits for dlm_send to
cancel work on the workqueues.

The dlm_send workqueue thread has called
tcp_connect_to_sock which calls dlm_nodeid_to_addr
which does a configfs lookup and blocks on a lock
held by dlm_controld in the rmdir path.

The solution here is to save the node addresses within
the lowcomms code so that the lowcomms workqueue does
not need to step through configfs to get a node address.

dlm_controld:
wait_for_completion+0x1d/0x20
__cancel_work_timer+0x1b3/0x1e0
cancel_work_sync+0x10/0x20
dlm_lowcomms_close+0x4c/0xb0 [dlm]
drop_comm+0x22/0x60 [dlm]
client_drop_item+0x26/0x50 [configfs]
configfs_rmdir+0x180/0x230 [configfs]
vfs_rmdir+0xbd/0xf0
do_rmdir+0x103/0x120
sys_rmdir+0x16/0x20

dlm_send:
mutex_lock+0x2b/0x50
get_comm+0x34/0x140 [dlm]
dlm_nodeid_to_addr+0x18/0xd0 [dlm]
tcp_connect_to_sock+0xf4/0x2d0 [dlm]
process_send_sockets+0x1d2/0x260 [dlm]
worker_thread+0x170/0x2a0

Signed-off-by: David Teigland <teigland@redhat.com>
2012-08-08 11:33:35 -05:00

1026 lines
26 KiB
C

/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
** Copyright (C) 2004-2011 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 <linux/kernel.h>
#include <linux/module.h>
#include <linux/configfs.h>
#include <linux/slab.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/dlmconstants.h>
#include <net/ipv6.h>
#include <net/sock.h>
#include "config.h"
#include "lowcomms.h"
/*
* /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid
* /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight
* /config/dlm/<cluster>/comms/<comm>/nodeid
* /config/dlm/<cluster>/comms/<comm>/local
* /config/dlm/<cluster>/comms/<comm>/addr (write only)
* /config/dlm/<cluster>/comms/<comm>/addr_list (read only)
* The <cluster> level is useless, but I haven't figured out how to avoid it.
*/
static struct config_group *space_list;
static struct config_group *comm_list;
static struct dlm_comm *local_comm;
static uint32_t dlm_comm_count;
struct dlm_clusters;
struct dlm_cluster;
struct dlm_spaces;
struct dlm_space;
struct dlm_comms;
struct dlm_comm;
struct dlm_nodes;
struct dlm_node;
static struct config_group *make_cluster(struct config_group *, const char *);
static void drop_cluster(struct config_group *, struct config_item *);
static void release_cluster(struct config_item *);
static struct config_group *make_space(struct config_group *, const char *);
static void drop_space(struct config_group *, struct config_item *);
static void release_space(struct config_item *);
static struct config_item *make_comm(struct config_group *, const char *);
static void drop_comm(struct config_group *, struct config_item *);
static void release_comm(struct config_item *);
static struct config_item *make_node(struct config_group *, const char *);
static void drop_node(struct config_group *, struct config_item *);
static void release_node(struct config_item *);
static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
char *buf);
static ssize_t store_cluster(struct config_item *i,
struct configfs_attribute *a,
const char *buf, size_t len);
static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
char *buf);
static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
const char *buf, size_t len);
static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
char *buf);
static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
const char *buf, size_t len);
static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf);
static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
size_t len);
static ssize_t comm_local_read(struct dlm_comm *cm, char *buf);
static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
size_t len);
static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf,
size_t len);
static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf);
static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf);
static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
size_t len);
static ssize_t node_weight_read(struct dlm_node *nd, char *buf);
static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
size_t len);
struct dlm_cluster {
struct config_group group;
unsigned int cl_tcp_port;
unsigned int cl_buffer_size;
unsigned int cl_rsbtbl_size;
unsigned int cl_recover_timer;
unsigned int cl_toss_secs;
unsigned int cl_scan_secs;
unsigned int cl_log_debug;
unsigned int cl_protocol;
unsigned int cl_timewarn_cs;
unsigned int cl_waitwarn_us;
unsigned int cl_new_rsb_count;
unsigned int cl_recover_callbacks;
char cl_cluster_name[DLM_LOCKSPACE_LEN];
};
enum {
CLUSTER_ATTR_TCP_PORT = 0,
CLUSTER_ATTR_BUFFER_SIZE,
CLUSTER_ATTR_RSBTBL_SIZE,
CLUSTER_ATTR_RECOVER_TIMER,
CLUSTER_ATTR_TOSS_SECS,
CLUSTER_ATTR_SCAN_SECS,
CLUSTER_ATTR_LOG_DEBUG,
CLUSTER_ATTR_PROTOCOL,
CLUSTER_ATTR_TIMEWARN_CS,
CLUSTER_ATTR_WAITWARN_US,
CLUSTER_ATTR_NEW_RSB_COUNT,
CLUSTER_ATTR_RECOVER_CALLBACKS,
CLUSTER_ATTR_CLUSTER_NAME,
};
struct cluster_attribute {
struct configfs_attribute attr;
ssize_t (*show)(struct dlm_cluster *, char *);
ssize_t (*store)(struct dlm_cluster *, const char *, size_t);
};
static ssize_t cluster_cluster_name_read(struct dlm_cluster *cl, char *buf)
{
return sprintf(buf, "%s\n", cl->cl_cluster_name);
}
static ssize_t cluster_cluster_name_write(struct dlm_cluster *cl,
const char *buf, size_t len)
{
strncpy(dlm_config.ci_cluster_name, buf, DLM_LOCKSPACE_LEN);
strncpy(cl->cl_cluster_name, buf, DLM_LOCKSPACE_LEN);
return len;
}
static struct cluster_attribute cluster_attr_cluster_name = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "cluster_name",
.ca_mode = S_IRUGO | S_IWUSR },
.show = cluster_cluster_name_read,
.store = cluster_cluster_name_write,
};
static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
int *info_field, int check_zero,
const char *buf, size_t len)
{
unsigned int x;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
x = simple_strtoul(buf, NULL, 0);
if (check_zero && !x)
return -EINVAL;
*cl_field = x;
*info_field = x;
return len;
}
#define CLUSTER_ATTR(name, check_zero) \
static ssize_t name##_write(struct dlm_cluster *cl, const char *buf, size_t len) \
{ \
return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name, \
check_zero, buf, len); \
} \
static ssize_t name##_read(struct dlm_cluster *cl, char *buf) \
{ \
return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name); \
} \
static struct cluster_attribute cluster_attr_##name = \
__CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
CLUSTER_ATTR(tcp_port, 1);
CLUSTER_ATTR(buffer_size, 1);
CLUSTER_ATTR(rsbtbl_size, 1);
CLUSTER_ATTR(recover_timer, 1);
CLUSTER_ATTR(toss_secs, 1);
CLUSTER_ATTR(scan_secs, 1);
CLUSTER_ATTR(log_debug, 0);
CLUSTER_ATTR(protocol, 0);
CLUSTER_ATTR(timewarn_cs, 1);
CLUSTER_ATTR(waitwarn_us, 0);
CLUSTER_ATTR(new_rsb_count, 0);
CLUSTER_ATTR(recover_callbacks, 0);
static struct configfs_attribute *cluster_attrs[] = {
[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
[CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size.attr,
[CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size.attr,
[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
[CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol.attr,
[CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
[CLUSTER_ATTR_WAITWARN_US] = &cluster_attr_waitwarn_us.attr,
[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count.attr,
[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks.attr,
[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name.attr,
NULL,
};
enum {
COMM_ATTR_NODEID = 0,
COMM_ATTR_LOCAL,
COMM_ATTR_ADDR,
COMM_ATTR_ADDR_LIST,
};
struct comm_attribute {
struct configfs_attribute attr;
ssize_t (*show)(struct dlm_comm *, char *);
ssize_t (*store)(struct dlm_comm *, const char *, size_t);
};
static struct comm_attribute comm_attr_nodeid = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "nodeid",
.ca_mode = S_IRUGO | S_IWUSR },
.show = comm_nodeid_read,
.store = comm_nodeid_write,
};
static struct comm_attribute comm_attr_local = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "local",
.ca_mode = S_IRUGO | S_IWUSR },
.show = comm_local_read,
.store = comm_local_write,
};
static struct comm_attribute comm_attr_addr = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "addr",
.ca_mode = S_IWUSR },
.store = comm_addr_write,
};
static struct comm_attribute comm_attr_addr_list = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "addr_list",
.ca_mode = S_IRUGO },
.show = comm_addr_list_read,
};
static struct configfs_attribute *comm_attrs[] = {
[COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
[COMM_ATTR_LOCAL] = &comm_attr_local.attr,
[COMM_ATTR_ADDR] = &comm_attr_addr.attr,
[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list.attr,
NULL,
};
enum {
NODE_ATTR_NODEID = 0,
NODE_ATTR_WEIGHT,
};
struct node_attribute {
struct configfs_attribute attr;
ssize_t (*show)(struct dlm_node *, char *);
ssize_t (*store)(struct dlm_node *, const char *, size_t);
};
static struct node_attribute node_attr_nodeid = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "nodeid",
.ca_mode = S_IRUGO | S_IWUSR },
.show = node_nodeid_read,
.store = node_nodeid_write,
};
static struct node_attribute node_attr_weight = {
.attr = { .ca_owner = THIS_MODULE,
.ca_name = "weight",
.ca_mode = S_IRUGO | S_IWUSR },
.show = node_weight_read,
.store = node_weight_write,
};
static struct configfs_attribute *node_attrs[] = {
[NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
[NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
NULL,
};
struct dlm_clusters {
struct configfs_subsystem subsys;
};
struct dlm_spaces {
struct config_group ss_group;
};
struct dlm_space {
struct config_group group;
struct list_head members;
struct mutex members_lock;
int members_count;
};
struct dlm_comms {
struct config_group cs_group;
};
struct dlm_comm {
struct config_item item;
int seq;
int nodeid;
int local;
int addr_count;
struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
};
struct dlm_nodes {
struct config_group ns_group;
};
struct dlm_node {
struct config_item item;
struct list_head list; /* space->members */
int nodeid;
int weight;
int new;
int comm_seq; /* copy of cm->seq when nd->nodeid is set */
};
static struct configfs_group_operations clusters_ops = {
.make_group = make_cluster,
.drop_item = drop_cluster,
};
static struct configfs_item_operations cluster_ops = {
.release = release_cluster,
.show_attribute = show_cluster,
.store_attribute = store_cluster,
};
static struct configfs_group_operations spaces_ops = {
.make_group = make_space,
.drop_item = drop_space,
};
static struct configfs_item_operations space_ops = {
.release = release_space,
};
static struct configfs_group_operations comms_ops = {
.make_item = make_comm,
.drop_item = drop_comm,
};
static struct configfs_item_operations comm_ops = {
.release = release_comm,
.show_attribute = show_comm,
.store_attribute = store_comm,
};
static struct configfs_group_operations nodes_ops = {
.make_item = make_node,
.drop_item = drop_node,
};
static struct configfs_item_operations node_ops = {
.release = release_node,
.show_attribute = show_node,
.store_attribute = store_node,
};
static struct config_item_type clusters_type = {
.ct_group_ops = &clusters_ops,
.ct_owner = THIS_MODULE,
};
static struct config_item_type cluster_type = {
.ct_item_ops = &cluster_ops,
.ct_attrs = cluster_attrs,
.ct_owner = THIS_MODULE,
};
static struct config_item_type spaces_type = {
.ct_group_ops = &spaces_ops,
.ct_owner = THIS_MODULE,
};
static struct config_item_type space_type = {
.ct_item_ops = &space_ops,
.ct_owner = THIS_MODULE,
};
static struct config_item_type comms_type = {
.ct_group_ops = &comms_ops,
.ct_owner = THIS_MODULE,
};
static struct config_item_type comm_type = {
.ct_item_ops = &comm_ops,
.ct_attrs = comm_attrs,
.ct_owner = THIS_MODULE,
};
static struct config_item_type nodes_type = {
.ct_group_ops = &nodes_ops,
.ct_owner = THIS_MODULE,
};
static struct config_item_type node_type = {
.ct_item_ops = &node_ops,
.ct_attrs = node_attrs,
.ct_owner = THIS_MODULE,
};
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 *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 *config_item_to_comm(struct config_item *i)
{
return i ? container_of(i, struct dlm_comm, item) : NULL;
}
static struct dlm_node *config_item_to_node(struct config_item *i)
{
return i ? container_of(i, struct dlm_node, item) : NULL;
}
static struct config_group *make_cluster(struct config_group *g,
const char *name)
{
struct dlm_cluster *cl = NULL;
struct dlm_spaces *sps = NULL;
struct dlm_comms *cms = NULL;
void *gps = NULL;
cl = kzalloc(sizeof(struct dlm_cluster), GFP_NOFS);
gps = kcalloc(3, sizeof(struct config_group *), GFP_NOFS);
sps = kzalloc(sizeof(struct dlm_spaces), GFP_NOFS);
cms = kzalloc(sizeof(struct dlm_comms), GFP_NOFS);
if (!cl || !gps || !sps || !cms)
goto fail;
config_group_init_type_name(&cl->group, name, &cluster_type);
config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
cl->group.default_groups = gps;
cl->group.default_groups[0] = &sps->ss_group;
cl->group.default_groups[1] = &cms->cs_group;
cl->group.default_groups[2] = NULL;
cl->cl_tcp_port = dlm_config.ci_tcp_port;
cl->cl_buffer_size = dlm_config.ci_buffer_size;
cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
cl->cl_recover_timer = dlm_config.ci_recover_timer;
cl->cl_toss_secs = dlm_config.ci_toss_secs;
cl->cl_scan_secs = dlm_config.ci_scan_secs;
cl->cl_log_debug = dlm_config.ci_log_debug;
cl->cl_protocol = dlm_config.ci_protocol;
cl->cl_timewarn_cs = dlm_config.ci_timewarn_cs;
cl->cl_waitwarn_us = dlm_config.ci_waitwarn_us;
cl->cl_new_rsb_count = dlm_config.ci_new_rsb_count;
cl->cl_recover_callbacks = dlm_config.ci_recover_callbacks;
memcpy(cl->cl_cluster_name, dlm_config.ci_cluster_name,
DLM_LOCKSPACE_LEN);
space_list = &sps->ss_group;
comm_list = &cms->cs_group;
return &cl->group;
fail:
kfree(cl);
kfree(gps);
kfree(sps);
kfree(cms);
return ERR_PTR(-ENOMEM);
}
static void drop_cluster(struct config_group *g, struct config_item *i)
{
struct dlm_cluster *cl = config_item_to_cluster(i);
struct config_item *tmp;
int j;
for (j = 0; cl->group.default_groups[j]; j++) {
tmp = &cl->group.default_groups[j]->cg_item;
cl->group.default_groups[j] = NULL;
config_item_put(tmp);
}
space_list = NULL;
comm_list = NULL;
config_item_put(i);
}
static void release_cluster(struct config_item *i)
{
struct dlm_cluster *cl = config_item_to_cluster(i);
kfree(cl->group.default_groups);
kfree(cl);
}
static struct config_group *make_space(struct config_group *g, const char *name)
{
struct dlm_space *sp = NULL;
struct dlm_nodes *nds = NULL;
void *gps = NULL;
sp = kzalloc(sizeof(struct dlm_space), GFP_NOFS);
gps = kcalloc(2, sizeof(struct config_group *), GFP_NOFS);
nds = kzalloc(sizeof(struct dlm_nodes), GFP_NOFS);
if (!sp || !gps || !nds)
goto fail;
config_group_init_type_name(&sp->group, name, &space_type);
config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
sp->group.default_groups = gps;
sp->group.default_groups[0] = &nds->ns_group;
sp->group.default_groups[1] = NULL;
INIT_LIST_HEAD(&sp->members);
mutex_init(&sp->members_lock);
sp->members_count = 0;
return &sp->group;
fail:
kfree(sp);
kfree(gps);
kfree(nds);
return ERR_PTR(-ENOMEM);
}
static void drop_space(struct config_group *g, struct config_item *i)
{
struct dlm_space *sp = config_item_to_space(i);
struct config_item *tmp;
int j;
/* assert list_empty(&sp->members) */
for (j = 0; sp->group.default_groups[j]; j++) {
tmp = &sp->group.default_groups[j]->cg_item;
sp->group.default_groups[j] = NULL;
config_item_put(tmp);
}
config_item_put(i);
}
static void release_space(struct config_item *i)
{
struct dlm_space *sp = config_item_to_space(i);
kfree(sp->group.default_groups);
kfree(sp);
}
static struct config_item *make_comm(struct config_group *g, const char *name)
{
struct dlm_comm *cm;
cm = kzalloc(sizeof(struct dlm_comm), GFP_NOFS);
if (!cm)
return ERR_PTR(-ENOMEM);
config_item_init_type_name(&cm->item, name, &comm_type);
cm->seq = dlm_comm_count++;
if (!cm->seq)
cm->seq = dlm_comm_count++;
cm->nodeid = -1;
cm->local = 0;
cm->addr_count = 0;
return &cm->item;
}
static void drop_comm(struct config_group *g, struct config_item *i)
{
struct dlm_comm *cm = config_item_to_comm(i);
if (local_comm == cm)
local_comm = NULL;
dlm_lowcomms_close(cm->nodeid);
while (cm->addr_count--)
kfree(cm->addr[cm->addr_count]);
config_item_put(i);
}
static void release_comm(struct config_item *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 = config_item_to_space(g->cg_item.ci_parent);
struct dlm_node *nd;
nd = kzalloc(sizeof(struct dlm_node), GFP_NOFS);
if (!nd)
return ERR_PTR(-ENOMEM);
config_item_init_type_name(&nd->item, name, &node_type);
nd->nodeid = -1;
nd->weight = 1; /* default weight of 1 if none is set */
nd->new = 1; /* set to 0 once it's been read by dlm_nodeid_list() */
mutex_lock(&sp->members_lock);
list_add(&nd->list, &sp->members);
sp->members_count++;
mutex_unlock(&sp->members_lock);
return &nd->item;
}
static void drop_node(struct config_group *g, struct config_item *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);
sp->members_count--;
mutex_unlock(&sp->members_lock);
config_item_put(i);
}
static void release_node(struct config_item *i)
{
struct dlm_node *nd = config_item_to_node(i);
kfree(nd);
}
static struct dlm_clusters clusters_root = {
.subsys = {
.su_group = {
.cg_item = {
.ci_namebuf = "dlm",
.ci_type = &clusters_type,
},
},
},
};
int __init dlm_config_init(void)
{
config_group_init(&clusters_root.subsys.su_group);
mutex_init(&clusters_root.subsys.su_mutex);
return configfs_register_subsystem(&clusters_root.subsys);
}
void dlm_config_exit(void)
{
configfs_unregister_subsystem(&clusters_root.subsys);
}
/*
* Functions for user space to read/write attributes
*/
static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
char *buf)
{
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;
}
static ssize_t store_cluster(struct config_item *i,
struct configfs_attribute *a,
const char *buf, size_t len)
{
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;
}
static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
char *buf)
{
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;
}
static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
const char *buf, size_t len)
{
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;
}
static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf)
{
return sprintf(buf, "%d\n", cm->nodeid);
}
static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
size_t len)
{
cm->nodeid = simple_strtol(buf, NULL, 0);
return len;
}
static ssize_t comm_local_read(struct dlm_comm *cm, char *buf)
{
return sprintf(buf, "%d\n", cm->local);
}
static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
size_t len)
{
cm->local= simple_strtol(buf, NULL, 0);
if (cm->local && !local_comm)
local_comm = cm;
return len;
}
static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf, size_t len)
{
struct sockaddr_storage *addr;
int rv;
if (len != sizeof(struct sockaddr_storage))
return -EINVAL;
if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
return -ENOSPC;
addr = kzalloc(sizeof(*addr), GFP_NOFS);
if (!addr)
return -ENOMEM;
memcpy(addr, buf, len);
rv = dlm_lowcomms_addr(cm->nodeid, addr, len);
if (rv) {
kfree(addr);
return rv;
}
cm->addr[cm->addr_count++] = addr;
return len;
}
static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf)
{
ssize_t s;
ssize_t allowance;
int i;
struct sockaddr_storage *addr;
struct sockaddr_in *addr_in;
struct sockaddr_in6 *addr_in6;
/* Taken from ip6_addr_string() defined in lib/vsprintf.c */
char buf0[sizeof("AF_INET6 xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255\n")];
/* Derived from SIMPLE_ATTR_SIZE of fs/configfs/file.c */
allowance = 4096;
buf[0] = '\0';
for (i = 0; i < cm->addr_count; i++) {
addr = cm->addr[i];
switch(addr->ss_family) {
case AF_INET:
addr_in = (struct sockaddr_in *)addr;
s = sprintf(buf0, "AF_INET %pI4\n", &addr_in->sin_addr.s_addr);
break;
case AF_INET6:
addr_in6 = (struct sockaddr_in6 *)addr;
s = sprintf(buf0, "AF_INET6 %pI6\n", &addr_in6->sin6_addr);
break;
default:
s = sprintf(buf0, "%s\n", "<UNKNOWN>");
break;
}
allowance -= s;
if (allowance >= 0)
strcat(buf, buf0);
else {
allowance += s;
break;
}
}
return 4096 - allowance;
}
static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
char *buf)
{
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;
}
static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
const char *buf, size_t len)
{
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;
}
static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf)
{
return sprintf(buf, "%d\n", nd->nodeid);
}
static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
size_t len)
{
uint32_t seq = 0;
nd->nodeid = simple_strtol(buf, NULL, 0);
dlm_comm_seq(nd->nodeid, &seq);
nd->comm_seq = seq;
return len;
}
static ssize_t node_weight_read(struct dlm_node *nd, char *buf)
{
return sprintf(buf, "%d\n", nd->weight);
}
static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
size_t len)
{
nd->weight = simple_strtol(buf, NULL, 0);
return len;
}
/*
* Functions for the dlm to get the info that's been configured
*/
static struct dlm_space *get_space(char *name)
{
struct config_item *i;
if (!space_list)
return NULL;
mutex_lock(&space_list->cg_subsys->su_mutex);
i = config_group_find_item(space_list, name);
mutex_unlock(&space_list->cg_subsys->su_mutex);
return config_item_to_space(i);
}
static void put_space(struct dlm_space *sp)
{
config_item_put(&sp->group.cg_item);
}
static struct dlm_comm *get_comm(int nodeid)
{
struct config_item *i;
struct dlm_comm *cm = NULL;
int found = 0;
if (!comm_list)
return NULL;
mutex_lock(&clusters_root.subsys.su_mutex);
list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
cm = config_item_to_comm(i);
if (cm->nodeid != nodeid)
continue;
found = 1;
config_item_get(i);
break;
}
mutex_unlock(&clusters_root.subsys.su_mutex);
if (!found)
cm = NULL;
return cm;
}
static void put_comm(struct dlm_comm *cm)
{
config_item_put(&cm->item);
}
/* caller must free mem */
int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
int *count_out)
{
struct dlm_space *sp;
struct dlm_node *nd;
struct dlm_config_node *nodes, *node;
int rv, count;
sp = get_space(lsname);
if (!sp)
return -EEXIST;
mutex_lock(&sp->members_lock);
if (!sp->members_count) {
rv = -EINVAL;
printk(KERN_ERR "dlm: zero members_count\n");
goto out;
}
count = sp->members_count;
nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
if (!nodes) {
rv = -ENOMEM;
goto out;
}
node = nodes;
list_for_each_entry(nd, &sp->members, list) {
node->nodeid = nd->nodeid;
node->weight = nd->weight;
node->new = nd->new;
node->comm_seq = nd->comm_seq;
node++;
nd->new = 0;
}
*count_out = count;
*nodes_out = nodes;
rv = 0;
out:
mutex_unlock(&sp->members_lock);
put_space(sp);
return rv;
}
int dlm_comm_seq(int nodeid, uint32_t *seq)
{
struct dlm_comm *cm = get_comm(nodeid);
if (!cm)
return -EEXIST;
*seq = cm->seq;
put_comm(cm);
return 0;
}
int dlm_our_nodeid(void)
{
return local_comm ? local_comm->nodeid : 0;
}
/* num 0 is first addr, num 1 is second addr */
int dlm_our_addr(struct sockaddr_storage *addr, int num)
{
if (!local_comm)
return -1;
if (num + 1 > local_comm->addr_count)
return -1;
memcpy(addr, local_comm->addr[num], sizeof(*addr));
return 0;
}
/* Config file defaults */
#define DEFAULT_TCP_PORT 21064
#define DEFAULT_BUFFER_SIZE 4096
#define DEFAULT_RSBTBL_SIZE 1024
#define DEFAULT_RECOVER_TIMER 5
#define DEFAULT_TOSS_SECS 10
#define DEFAULT_SCAN_SECS 5
#define DEFAULT_LOG_DEBUG 0
#define DEFAULT_PROTOCOL 0
#define DEFAULT_TIMEWARN_CS 500 /* 5 sec = 500 centiseconds */
#define DEFAULT_WAITWARN_US 0
#define DEFAULT_NEW_RSB_COUNT 128
#define DEFAULT_RECOVER_CALLBACKS 0
#define DEFAULT_CLUSTER_NAME ""
struct dlm_config_info dlm_config = {
.ci_tcp_port = DEFAULT_TCP_PORT,
.ci_buffer_size = DEFAULT_BUFFER_SIZE,
.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
.ci_recover_timer = DEFAULT_RECOVER_TIMER,
.ci_toss_secs = DEFAULT_TOSS_SECS,
.ci_scan_secs = DEFAULT_SCAN_SECS,
.ci_log_debug = DEFAULT_LOG_DEBUG,
.ci_protocol = DEFAULT_PROTOCOL,
.ci_timewarn_cs = DEFAULT_TIMEWARN_CS,
.ci_waitwarn_us = DEFAULT_WAITWARN_US,
.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
.ci_cluster_name = DEFAULT_CLUSTER_NAME
};