// SPDX-License-Identifier: GPL-2.0-only
/******************************************************************************
*******************************************************************************
**
**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
**
**
*******************************************************************************
******************************************************************************/

#include <linux/kernel.h>
#include <linux/init.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 "midcomms.h"
#include "lowcomms.h"

/*
 * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid (refers to <node>)
 * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight
 * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/release_recover
 * /config/dlm/<cluster>/comms/<comm>/nodeid (refers to <comm>)
 * /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 struct configfs_attribute *comm_attrs[];
static struct configfs_attribute *node_attrs[];

const struct rhashtable_params dlm_rhash_rsb_params = {
        .nelem_hint = 3, /* start small */
        .key_len = DLM_RESNAME_MAXLEN,
        .key_offset = offsetof(struct dlm_rsb, res_name),
        .head_offset = offsetof(struct dlm_rsb, res_node),
        .automatic_shrinking = true,
};

struct dlm_cluster {
        struct config_group group;
        struct dlm_spaces *sps;
        struct dlm_comms *cms;
};

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;
}

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_LOG_INFO,
        CLUSTER_ATTR_PROTOCOL,
        CLUSTER_ATTR_MARK,
        CLUSTER_ATTR_NEW_RSB_COUNT,
        CLUSTER_ATTR_RECOVER_CALLBACKS,
        CLUSTER_ATTR_CLUSTER_NAME,
};

static ssize_t cluster_cluster_name_show(struct config_item *item, char *buf)
{
        return sprintf(buf, "%s\n", dlm_config.ci_cluster_name);
}

static ssize_t cluster_cluster_name_store(struct config_item *item,
                                          const char *buf, size_t len)
{
        strscpy(dlm_config.ci_cluster_name, buf,
                sizeof(dlm_config.ci_cluster_name));
        return len;
}

CONFIGFS_ATTR(cluster_, cluster_name);

static ssize_t cluster_tcp_port_show(struct config_item *item, char *buf)
{
        return sprintf(buf, "%u\n", be16_to_cpu(dlm_config.ci_tcp_port));
}

static int dlm_check_zero_and_dlm_running(unsigned int x)
{
        if (!x)
                return -EINVAL;

        if (dlm_lowcomms_is_running())
                return -EBUSY;

        return 0;
}

static ssize_t cluster_tcp_port_store(struct config_item *item,
                                      const char *buf, size_t len)
{
        int rc;
        u16 x;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        rc = kstrtou16(buf, 0, &x);
        if (rc)
                return rc;

        rc = dlm_check_zero_and_dlm_running(x);
        if (rc)
                return rc;

        dlm_config.ci_tcp_port = cpu_to_be16(x);
        return len;
}

CONFIGFS_ATTR(cluster_, tcp_port);

static ssize_t cluster_set(unsigned int *info_field,
                           int (*check_cb)(unsigned int x),
                           const char *buf, size_t len)
{
        unsigned int x;
        int rc;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
        rc = kstrtouint(buf, 0, &x);
        if (rc)
                return rc;

        if (check_cb) {
                rc = check_cb(x);
                if (rc)
                        return rc;
        }

        *info_field = x;

        return len;
}

#define CLUSTER_ATTR(name, check_cb)                                          \
static ssize_t cluster_##name##_store(struct config_item *item, \
                const char *buf, size_t len) \
{                                                                             \
        return cluster_set(&dlm_config.ci_##name, check_cb, buf, len);        \
}                                                                             \
static ssize_t cluster_##name##_show(struct config_item *item, char *buf)     \
{                                                                             \
        return snprintf(buf, PAGE_SIZE, "%u\n", dlm_config.ci_##name);        \
}                                                                             \
CONFIGFS_ATTR(cluster_, name);

static int dlm_check_protocol_and_dlm_running(unsigned int x)
{
        switch (x) {
        case 0:
                /* TCP */
                break;
        case 1:
                /* SCTP */
                if (!IS_ENABLED(CONFIG_IP_SCTP))
                        return -EOPNOTSUPP;

                break;
        default:
                return -EINVAL;
        }

        if (dlm_lowcomms_is_running())
                return -EBUSY;

        return 0;
}

static int dlm_check_zero(unsigned int x)
{
        if (!x)
                return -EINVAL;

        return 0;
}

static int dlm_check_buffer_size(unsigned int x)
{
        if (x < DLM_MAX_SOCKET_BUFSIZE)
                return -EINVAL;

        return 0;
}

CLUSTER_ATTR(buffer_size, dlm_check_buffer_size);
CLUSTER_ATTR(rsbtbl_size, dlm_check_zero);
CLUSTER_ATTR(recover_timer, dlm_check_zero);
CLUSTER_ATTR(toss_secs, dlm_check_zero);
CLUSTER_ATTR(scan_secs, dlm_check_zero);
CLUSTER_ATTR(log_debug, NULL);
CLUSTER_ATTR(log_info, NULL);
CLUSTER_ATTR(protocol, dlm_check_protocol_and_dlm_running);
CLUSTER_ATTR(mark, NULL);
CLUSTER_ATTR(new_rsb_count, NULL);
CLUSTER_ATTR(recover_callbacks, NULL);

static struct configfs_attribute *cluster_attrs[] = {
        [CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port,
        [CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size,
        [CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size,
        [CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer,
        [CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs,
        [CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs,
        [CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug,
        [CLUSTER_ATTR_LOG_INFO] = &cluster_attr_log_info,
        [CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol,
        [CLUSTER_ATTR_MARK] = &cluster_attr_mark,
        [CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count,
        [CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks,
        [CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name,
        NULL,
};

enum {
        COMM_ATTR_NODEID = 0,
        COMM_ATTR_LOCAL,
        COMM_ATTR_ADDR,
        COMM_ATTR_ADDR_LIST,
        COMM_ATTR_MARK,
};

enum {
        NODE_ATTR_NODEID = 0,
        NODE_ATTR_WEIGHT,
        NODE_ATTR_RELEASE_RECOVER,
};

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 list_head members_gone;
        int members_gone_count;
        struct mutex members_lock;
        int members_count;
        struct dlm_nodes *nds;
};

struct dlm_comms {
        struct config_group cs_group;
};

struct dlm_comm {
        struct config_item item;
        int seq;
        int nodeid;
        int local;
        int addr_count;
        unsigned int mark;
        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 */
        unsigned int release_recover;
};

struct dlm_member_gone {
        int nodeid;
        unsigned int release_recover;

        struct list_head list; /* space->members_gone */
};

static const struct configfs_group_operations clusters_ops = {
        .make_group = make_cluster,
        .drop_item = drop_cluster,
};

static const struct configfs_item_operations cluster_ops = {
        .release = release_cluster,
};

static const struct configfs_group_operations spaces_ops = {
        .make_group = make_space,
        .drop_item = drop_space,
};

static const struct configfs_item_operations space_ops = {
        .release = release_space,
};

static const struct configfs_group_operations comms_ops = {
        .make_item = make_comm,
        .drop_item = drop_comm,
};

static const struct configfs_item_operations comm_ops = {
        .release = release_comm,
};

static const struct configfs_group_operations nodes_ops = {
        .make_item = make_node,
        .drop_item = drop_node,
};

static const struct configfs_item_operations node_ops = {
        .release = release_node,
};

static const struct config_item_type clusters_type = {
        .ct_group_ops = &clusters_ops,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type cluster_type = {
        .ct_item_ops = &cluster_ops,
        .ct_attrs = cluster_attrs,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type spaces_type = {
        .ct_group_ops = &spaces_ops,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type space_type = {
        .ct_item_ops = &space_ops,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type comms_type = {
        .ct_group_ops = &comms_ops,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type comm_type = {
        .ct_item_ops = &comm_ops,
        .ct_attrs = comm_attrs,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type nodes_type = {
        .ct_group_ops = &nodes_ops,
        .ct_owner = THIS_MODULE,
};

static const struct config_item_type node_type = {
        .ct_item_ops = &node_ops,
        .ct_attrs = node_attrs,
        .ct_owner = THIS_MODULE,
};

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;

        cl = kzalloc_obj(struct dlm_cluster, GFP_NOFS);
        sps = kzalloc_obj(struct dlm_spaces, GFP_NOFS);
        cms = kzalloc_obj(struct dlm_comms, GFP_NOFS);

        if (!cl || !sps || !cms)
                goto fail;

        cl->sps = sps;
        cl->cms = cms;

        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);

        configfs_add_default_group(&sps->ss_group, &cl->group);
        configfs_add_default_group(&cms->cs_group, &cl->group);

        space_list = &sps->ss_group;
        comm_list = &cms->cs_group;
        return &cl->group;

 fail:
        kfree(cl);
        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);

        configfs_remove_default_groups(&cl->group);

        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->sps);
        kfree(cl->cms);
        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;

        sp = kzalloc_obj(struct dlm_space, GFP_NOFS);
        nds = kzalloc_obj(struct dlm_nodes, GFP_NOFS);

        if (!sp || !nds)
                goto fail;

        config_group_init_type_name(&sp->group, name, &space_type);

        config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
        configfs_add_default_group(&nds->ns_group, &sp->group);

        INIT_LIST_HEAD(&sp->members);
        INIT_LIST_HEAD(&sp->members_gone);
        mutex_init(&sp->members_lock);
        sp->members_count = 0;
        sp->nds = nds;
        return &sp->group;

 fail:
        kfree(sp);
        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);

        /* assert list_empty(&sp->members) */

        configfs_remove_default_groups(&sp->group);
        config_item_put(i);
}

static void release_space(struct config_item *i)
{
        struct dlm_space *sp = config_item_to_space(i);
        kfree(sp->nds);
        kfree(sp);
}

static struct config_item *make_comm(struct config_group *g, const char *name)
{
        struct dlm_comm *cm;
        unsigned int nodeid;
        int rv;

        rv = kstrtouint(name, 0, &nodeid);
        if (rv)
                return ERR_PTR(rv);

        cm = kzalloc_obj(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 = nodeid;
        cm->local = 0;
        cm->addr_count = 0;
        cm->mark = 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_midcomms_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);
        unsigned int nodeid;
        struct dlm_node *nd;
        uint32_t seq = 0;
        int rv;

        rv = kstrtouint(name, 0, &nodeid);
        if (rv)
                return ERR_PTR(rv);

        nd = kzalloc_obj(struct dlm_node, GFP_NOFS);
        if (!nd)
                return ERR_PTR(-ENOMEM);

        config_item_init_type_name(&nd->item, name, &node_type);
        nd->nodeid = nodeid;
        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() */
        dlm_comm_seq(nodeid, &seq, true);
        nd->comm_seq = seq;

        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);
        struct dlm_member_gone *mb_gone;

        mb_gone = kzalloc_obj(*mb_gone);
        if (!mb_gone)
                return;

        mutex_lock(&sp->members_lock);
        list_del(&nd->list);
        sp->members_count--;

        mb_gone->nodeid = nd->nodeid;
        mb_gone->release_recover = nd->release_recover;
        list_add(&mb_gone->list, &sp->members_gone);
        sp->members_gone_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 comm_nodeid_show(struct config_item *item, char *buf)
{
        unsigned int nodeid;
        int rv;

        rv = kstrtouint(config_item_name(item), 0, &nodeid);
        if (WARN_ON(rv))
                return rv;

        return sprintf(buf, "%u\n", nodeid);
}

static ssize_t comm_nodeid_store(struct config_item *item, const char *buf,
                                 size_t len)
{
        return len;
}

static ssize_t comm_local_show(struct config_item *item, char *buf)
{
        return sprintf(buf, "%d\n", config_item_to_comm(item)->local);
}

static ssize_t comm_local_store(struct config_item *item, const char *buf,
                                size_t len)
{
        struct dlm_comm *cm = config_item_to_comm(item);
        int rc = kstrtoint(buf, 0, &cm->local);

        if (rc)
                return rc;
        if (cm->local && !local_comm)
                local_comm = cm;
        return len;
}

static ssize_t comm_addr_store(struct config_item *item, const char *buf,
                size_t len)
{
        struct dlm_comm *cm = config_item_to_comm(item);
        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_obj(*addr, GFP_NOFS);
        if (!addr)
                return -ENOMEM;

        memcpy(addr, buf, len);

        rv = dlm_midcomms_addr(cm->nodeid, addr);
        if (rv) {
                kfree(addr);
                return rv;
        }

        cm->addr[cm->addr_count++] = addr;
        return len;
}

static ssize_t comm_addr_list_show(struct config_item *item, char *buf)
{
        struct dlm_comm *cm = config_item_to_comm(item);
        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 comm_mark_show(struct config_item *item, char *buf)
{
        return sprintf(buf, "%u\n", config_item_to_comm(item)->mark);
}

static ssize_t comm_mark_store(struct config_item *item, const char *buf,
                               size_t len)
{
        struct dlm_comm *comm;
        unsigned int mark;
        int rc;

        rc = kstrtouint(buf, 0, &mark);
        if (rc)
                return rc;

        if (mark == 0)
                mark = dlm_config.ci_mark;

        comm = config_item_to_comm(item);
        rc = dlm_lowcomms_nodes_set_mark(comm->nodeid, mark);
        if (rc)
                return rc;

        comm->mark = mark;
        return len;
}

CONFIGFS_ATTR(comm_, nodeid);
CONFIGFS_ATTR(comm_, local);
CONFIGFS_ATTR(comm_, mark);
CONFIGFS_ATTR_WO(comm_, addr);
CONFIGFS_ATTR_RO(comm_, addr_list);

static struct configfs_attribute *comm_attrs[] = {
        [COMM_ATTR_NODEID] = &comm_attr_nodeid,
        [COMM_ATTR_LOCAL] = &comm_attr_local,
        [COMM_ATTR_ADDR] = &comm_attr_addr,
        [COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list,
        [COMM_ATTR_MARK] = &comm_attr_mark,
        NULL,
};

static ssize_t node_nodeid_show(struct config_item *item, char *buf)
{
        unsigned int nodeid;
        int rv;

        rv = kstrtouint(config_item_name(item), 0, &nodeid);
        if (WARN_ON(rv))
                return rv;

        return sprintf(buf, "%u\n", nodeid);
}

static ssize_t node_nodeid_store(struct config_item *item, const char *buf,
                                 size_t len)
{
        return len;
}

static ssize_t node_weight_show(struct config_item *item, char *buf)
{
        return sprintf(buf, "%d\n", config_item_to_node(item)->weight);
}

static ssize_t node_weight_store(struct config_item *item, const char *buf,
                                 size_t len)
{
        int rc = kstrtoint(buf, 0, &config_item_to_node(item)->weight);

        if (rc)
                return rc;
        return len;
}

static ssize_t node_release_recover_show(struct config_item *item, char *buf)
{
        struct dlm_node *n = config_item_to_node(item);

        return sprintf(buf, "%u\n", n->release_recover);
}

static ssize_t node_release_recover_store(struct config_item *item,
                                          const char *buf, size_t len)
{
        struct dlm_node *n = config_item_to_node(item);
        int rc;

        rc = kstrtouint(buf, 0, &n->release_recover);
        if (rc)
                return rc;

        return len;
}

CONFIGFS_ATTR(node_, nodeid);
CONFIGFS_ATTR(node_, weight);
CONFIGFS_ATTR(node_, release_recover);

static struct configfs_attribute *node_attrs[] = {
        [NODE_ATTR_NODEID] = &node_attr_nodeid,
        [NODE_ATTR_WEIGHT] = &node_attr_weight,
        [NODE_ATTR_RELEASE_RECOVER] = &node_attr_release_recover,
        NULL,
};

/*
 * 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;

        WARN_ON_ONCE(!mutex_is_locked(&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;
        }

        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_member_gone *mb_gone, *mb_safe;
        struct dlm_config_node *nodes, *node;
        struct dlm_space *sp;
        struct dlm_node *nd;
        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 + sp->members_gone_count;

        nodes = kzalloc_objs(struct dlm_config_node, count, 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;
        }

        /* we delay the remove on nodes until here as configfs does
         * not support addtional attributes for rmdir().
         */
        list_for_each_entry_safe(mb_gone, mb_safe, &sp->members_gone, list) {
                node->nodeid = mb_gone->nodeid;
                node->release_recover = mb_gone->release_recover;
                node->gone = true;
                node++;

                list_del(&mb_gone->list);
                sp->members_gone_count--;
                kfree(mb_gone);
        }

        *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, bool locked)
{
        struct dlm_comm *cm;

        if (locked) {
                cm = get_comm(nodeid);
        } else {
                mutex_lock(&clusters_root.subsys.su_mutex);
                cm = get_comm(nodeid);
                mutex_unlock(&clusters_root.subsys.su_mutex);
        }
        if (!cm)
                return -ENOENT;

        *seq = cm->seq;
        put_comm(cm);
        return 0;
}

int dlm_our_nodeid(void)
{
        return local_comm->nodeid;
}

/* 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_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_LOG_INFO           1
#define DEFAULT_PROTOCOL           DLM_PROTO_TCP
#define DEFAULT_MARK               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 = cpu_to_be16(DEFAULT_TCP_PORT),
        .ci_buffer_size = DLM_MAX_SOCKET_BUFSIZE,
        .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_log_info = DEFAULT_LOG_INFO,
        .ci_protocol = DEFAULT_PROTOCOL,
        .ci_mark = DEFAULT_MARK,
        .ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
        .ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
        .ci_cluster_name = DEFAULT_CLUSTER_NAME
};