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Diffstat (limited to '')
| -rw-r--r-- | fs/ocfs2/dlm/dlmdomain.c | 2391 |
1 files changed, 2391 insertions, 0 deletions
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c new file mode 100644 index 000000000..2acd58ba9 --- /dev/null +++ b/fs/ocfs2/dlm/dlmdomain.c @@ -0,0 +1,2391 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmdomain.c + * + * defines domain join / leave apis + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/debugfs.h> +#include <linux/sched/signal.h> + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdomain.h" +#include "dlmdebug.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN) +#include "cluster/masklog.h" + +/* + * ocfs2 node maps are array of long int, which limits to send them freely + * across the wire due to endianness issues. To workaround this, we convert + * long ints to byte arrays. Following 3 routines are helper functions to + * set/test/copy bits within those array of bytes + */ +static inline void byte_set_bit(u8 nr, u8 map[]) +{ + map[nr >> 3] |= (1UL << (nr & 7)); +} + +static inline int byte_test_bit(u8 nr, u8 map[]) +{ + return ((1UL << (nr & 7)) & (map[nr >> 3])) != 0; +} + +static inline void byte_copymap(u8 dmap[], unsigned long smap[], + unsigned int sz) +{ + unsigned int nn; + + if (!sz) + return; + + memset(dmap, 0, ((sz + 7) >> 3)); + for (nn = 0 ; nn < sz; nn++) + if (test_bit(nn, smap)) + byte_set_bit(nn, dmap); +} + +static void dlm_free_pagevec(void **vec, int pages) +{ + while (pages--) + free_page((unsigned long)vec[pages]); + kfree(vec); +} + +static void **dlm_alloc_pagevec(int pages) +{ + void **vec = kmalloc_array(pages, sizeof(void *), GFP_KERNEL); + int i; + + if (!vec) + return NULL; + + for (i = 0; i < pages; i++) + if (!(vec[i] = (void *)__get_free_page(GFP_KERNEL))) + goto out_free; + + mlog(0, "Allocated DLM hash pagevec; %d pages (%lu expected), %lu buckets per page\n", + pages, (unsigned long)DLM_HASH_PAGES, + (unsigned long)DLM_BUCKETS_PER_PAGE); + return vec; +out_free: + dlm_free_pagevec(vec, i); + return NULL; +} + +/* + * + * spinlock lock ordering: if multiple locks are needed, obey this ordering: + * dlm_domain_lock + * struct dlm_ctxt->spinlock + * struct dlm_lock_resource->spinlock + * struct dlm_ctxt->master_lock + * struct dlm_ctxt->ast_lock + * dlm_master_list_entry->spinlock + * dlm_lock->spinlock + * + */ + +DEFINE_SPINLOCK(dlm_domain_lock); +LIST_HEAD(dlm_domains); +static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events); + +/* + * The supported protocol version for DLM communication. Running domains + * will have a negotiated version with the same major number and a minor + * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should + * be used to determine what a running domain is actually using. + * + * New in version 1.1: + * - Message DLM_QUERY_REGION added to support global heartbeat + * - Message DLM_QUERY_NODEINFO added to allow online node removes + * New in version 1.2: + * - Message DLM_BEGIN_EXIT_DOMAIN_MSG added to mark start of exit domain + * New in version 1.3: + * - Message DLM_DEREF_LOCKRES_DONE added to inform non-master that the + * refmap is cleared + */ +static const struct dlm_protocol_version dlm_protocol = { + .pv_major = 1, + .pv_minor = 3, +}; + +#define DLM_DOMAIN_BACKOFF_MS 200 + +static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data); +static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data); +static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data); +static int dlm_query_region_handler(struct o2net_msg *msg, u32 len, + void *data, void **ret_data); +static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data); +static int dlm_protocol_compare(struct dlm_protocol_version *existing, + struct dlm_protocol_version *request); + +static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm); + +void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + if (hlist_unhashed(&res->hash_node)) + return; + + mlog(0, "%s: Unhash res %.*s\n", dlm->name, res->lockname.len, + res->lockname.name); + hlist_del_init(&res->hash_node); + dlm_lockres_put(res); +} + +void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) +{ + struct hlist_head *bucket; + + assert_spin_locked(&dlm->spinlock); + + bucket = dlm_lockres_hash(dlm, res->lockname.hash); + + /* get a reference for our hashtable */ + dlm_lockres_get(res); + + hlist_add_head(&res->hash_node, bucket); + + mlog(0, "%s: Hash res %.*s\n", dlm->name, res->lockname.len, + res->lockname.name); +} + +struct dlm_lock_resource * __dlm_lookup_lockres_full(struct dlm_ctxt *dlm, + const char *name, + unsigned int len, + unsigned int hash) +{ + struct hlist_head *bucket; + struct dlm_lock_resource *res; + + mlog(0, "%.*s\n", len, name); + + assert_spin_locked(&dlm->spinlock); + + bucket = dlm_lockres_hash(dlm, hash); + + hlist_for_each_entry(res, bucket, hash_node) { + if (res->lockname.name[0] != name[0]) + continue; + if (unlikely(res->lockname.len != len)) + continue; + if (memcmp(res->lockname.name + 1, name + 1, len - 1)) + continue; + dlm_lockres_get(res); + return res; + } + return NULL; +} + +/* intended to be called by functions which do not care about lock + * resources which are being purged (most net _handler functions). + * this will return NULL for any lock resource which is found but + * currently in the process of dropping its mastery reference. + * use __dlm_lookup_lockres_full when you need the lock resource + * regardless (e.g. dlm_get_lock_resource) */ +struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len, + unsigned int hash) +{ + struct dlm_lock_resource *res = NULL; + + mlog(0, "%.*s\n", len, name); + + assert_spin_locked(&dlm->spinlock); + + res = __dlm_lookup_lockres_full(dlm, name, len, hash); + if (res) { + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_DROPPING_REF) { + spin_unlock(&res->spinlock); + dlm_lockres_put(res); + return NULL; + } + spin_unlock(&res->spinlock); + } + + return res; +} + +struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm, + const char *name, + unsigned int len) +{ + struct dlm_lock_resource *res; + unsigned int hash = dlm_lockid_hash(name, len); + + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, name, len, hash); + spin_unlock(&dlm->spinlock); + return res; +} + +static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len) +{ + struct dlm_ctxt *tmp; + + assert_spin_locked(&dlm_domain_lock); + + /* tmp->name here is always NULL terminated, + * but domain may not be! */ + list_for_each_entry(tmp, &dlm_domains, list) { + if (strlen(tmp->name) == len && + memcmp(tmp->name, domain, len)==0) + return tmp; + } + + return NULL; +} + +/* For null terminated domain strings ONLY */ +static struct dlm_ctxt * __dlm_lookup_domain(const char *domain) +{ + assert_spin_locked(&dlm_domain_lock); + + return __dlm_lookup_domain_full(domain, strlen(domain)); +} + + +/* returns true on one of two conditions: + * 1) the domain does not exist + * 2) the domain exists and it's state is "joined" */ +static int dlm_wait_on_domain_helper(const char *domain) +{ + int ret = 0; + struct dlm_ctxt *tmp = NULL; + + spin_lock(&dlm_domain_lock); + + tmp = __dlm_lookup_domain(domain); + if (!tmp) + ret = 1; + else if (tmp->dlm_state == DLM_CTXT_JOINED) + ret = 1; + + spin_unlock(&dlm_domain_lock); + return ret; +} + +static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm) +{ + dlm_destroy_debugfs_subroot(dlm); + + if (dlm->lockres_hash) + dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES); + + if (dlm->master_hash) + dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES); + + kfree(dlm->name); + kfree(dlm); +} + +/* A little strange - this function will be called while holding + * dlm_domain_lock and is expected to be holding it on the way out. We + * will however drop and reacquire it multiple times */ +static void dlm_ctxt_release(struct kref *kref) +{ + struct dlm_ctxt *dlm; + + dlm = container_of(kref, struct dlm_ctxt, dlm_refs); + + BUG_ON(dlm->num_joins); + BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED); + + /* we may still be in the list if we hit an error during join. */ + list_del_init(&dlm->list); + + spin_unlock(&dlm_domain_lock); + + mlog(0, "freeing memory from domain %s\n", dlm->name); + + wake_up(&dlm_domain_events); + + dlm_free_ctxt_mem(dlm); + + spin_lock(&dlm_domain_lock); +} + +void dlm_put(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm_domain_lock); + kref_put(&dlm->dlm_refs, dlm_ctxt_release); + spin_unlock(&dlm_domain_lock); +} + +static void __dlm_get(struct dlm_ctxt *dlm) +{ + kref_get(&dlm->dlm_refs); +} + +/* given a questionable reference to a dlm object, gets a reference if + * it can find it in the list, otherwise returns NULL in which case + * you shouldn't trust your pointer. */ +struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm) +{ + struct dlm_ctxt *target; + struct dlm_ctxt *ret = NULL; + + spin_lock(&dlm_domain_lock); + + list_for_each_entry(target, &dlm_domains, list) { + if (target == dlm) { + __dlm_get(target); + ret = target; + break; + } + } + + spin_unlock(&dlm_domain_lock); + + return ret; +} + +int dlm_domain_fully_joined(struct dlm_ctxt *dlm) +{ + int ret; + + spin_lock(&dlm_domain_lock); + ret = (dlm->dlm_state == DLM_CTXT_JOINED) || + (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN); + spin_unlock(&dlm_domain_lock); + + return ret; +} + +static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm) +{ + if (dlm->dlm_worker) { + destroy_workqueue(dlm->dlm_worker); + dlm->dlm_worker = NULL; + } +} + +static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm) +{ + dlm_unregister_domain_handlers(dlm); + dlm_debug_shutdown(dlm); + dlm_complete_thread(dlm); + dlm_complete_recovery_thread(dlm); + dlm_destroy_dlm_worker(dlm); + + /* We've left the domain. Now we can take ourselves out of the + * list and allow the kref stuff to help us free the + * memory. */ + spin_lock(&dlm_domain_lock); + list_del_init(&dlm->list); + spin_unlock(&dlm_domain_lock); + + /* Wake up anyone waiting for us to remove this domain */ + wake_up(&dlm_domain_events); +} + +static int dlm_migrate_all_locks(struct dlm_ctxt *dlm) +{ + int i, num, n, ret = 0; + struct dlm_lock_resource *res; + struct hlist_node *iter; + struct hlist_head *bucket; + int dropped; + + mlog(0, "Migrating locks from domain %s\n", dlm->name); + + num = 0; + spin_lock(&dlm->spinlock); + for (i = 0; i < DLM_HASH_BUCKETS; i++) { +redo_bucket: + n = 0; + bucket = dlm_lockres_hash(dlm, i); + iter = bucket->first; + while (iter) { + n++; + res = hlist_entry(iter, struct dlm_lock_resource, + hash_node); + dlm_lockres_get(res); + /* migrate, if necessary. this will drop the dlm + * spinlock and retake it if it does migration. */ + dropped = dlm_empty_lockres(dlm, res); + + spin_lock(&res->spinlock); + if (dropped) + __dlm_lockres_calc_usage(dlm, res); + else + iter = res->hash_node.next; + spin_unlock(&res->spinlock); + + dlm_lockres_put(res); + + if (dropped) { + cond_resched_lock(&dlm->spinlock); + goto redo_bucket; + } + } + cond_resched_lock(&dlm->spinlock); + num += n; + } + + if (!num) { + if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) { + mlog(0, "%s: perhaps there are more lock resources " + "need to be migrated after dlm recovery\n", dlm->name); + ret = -EAGAIN; + } else { + mlog(0, "%s: we won't do dlm recovery after migrating " + "all lock resources\n", dlm->name); + dlm->migrate_done = 1; + } + } + + spin_unlock(&dlm->spinlock); + wake_up(&dlm->dlm_thread_wq); + + /* let the dlm thread take care of purging, keep scanning until + * nothing remains in the hash */ + if (num) { + mlog(0, "%s: %d lock resources in hash last pass\n", + dlm->name, num); + ret = -EAGAIN; + } + mlog(0, "DONE Migrating locks from domain %s\n", dlm->name); + return ret; +} + +static int dlm_no_joining_node(struct dlm_ctxt *dlm) +{ + int ret; + + spin_lock(&dlm->spinlock); + ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN; + spin_unlock(&dlm->spinlock); + + return ret; +} + +static int dlm_begin_exit_domain_handler(struct o2net_msg *msg, u32 len, + void *data, void **ret_data) +{ + struct dlm_ctxt *dlm = data; + unsigned int node; + struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf; + + if (!dlm_grab(dlm)) + return 0; + + node = exit_msg->node_idx; + mlog(0, "%s: Node %u sent a begin exit domain message\n", dlm->name, node); + + spin_lock(&dlm->spinlock); + set_bit(node, dlm->exit_domain_map); + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); + + return 0; +} + +static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm) +{ + /* Yikes, a double spinlock! I need domain_lock for the dlm + * state and the dlm spinlock for join state... Sorry! */ +again: + spin_lock(&dlm_domain_lock); + spin_lock(&dlm->spinlock); + + if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "Node %d is joining, we wait on it.\n", + dlm->joining_node); + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); + + wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm)); + goto again; + } + + dlm->dlm_state = DLM_CTXT_LEAVING; + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); +} + +static void __dlm_print_nodes(struct dlm_ctxt *dlm) +{ + int node = -1, num = 0; + + assert_spin_locked(&dlm->spinlock); + + printk("( "); + while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + printk("%d ", node); + ++num; + } + printk(") %u nodes\n", num); +} + +static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data) +{ + struct dlm_ctxt *dlm = data; + unsigned int node; + struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf; + + mlog(0, "%p %u %p", msg, len, data); + + if (!dlm_grab(dlm)) + return 0; + + node = exit_msg->node_idx; + + spin_lock(&dlm->spinlock); + clear_bit(node, dlm->domain_map); + clear_bit(node, dlm->exit_domain_map); + printk(KERN_NOTICE "o2dlm: Node %u leaves domain %s ", node, dlm->name); + __dlm_print_nodes(dlm); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, node, 0); + + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); + + return 0; +} + +static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm, u32 msg_type, + unsigned int node) +{ + int status; + struct dlm_exit_domain leave_msg; + + mlog(0, "%s: Sending domain exit message %u to node %u\n", dlm->name, + msg_type, node); + + memset(&leave_msg, 0, sizeof(leave_msg)); + leave_msg.node_idx = dlm->node_num; + + status = o2net_send_message(msg_type, dlm->key, &leave_msg, + sizeof(leave_msg), node, NULL); + if (status < 0) + mlog(ML_ERROR, "Error %d sending domain exit message %u " + "to node %u on domain %s\n", status, msg_type, node, + dlm->name); + + return status; +} + +static void dlm_begin_exit_domain(struct dlm_ctxt *dlm) +{ + int node = -1; + + /* Support for begin exit domain was added in 1.2 */ + if (dlm->dlm_locking_proto.pv_major == 1 && + dlm->dlm_locking_proto.pv_minor < 2) + return; + + /* + * Unlike DLM_EXIT_DOMAIN_MSG, DLM_BEGIN_EXIT_DOMAIN_MSG is purely + * informational. Meaning if a node does not receive the message, + * so be it. + */ + spin_lock(&dlm->spinlock); + while (1) { + node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, node + 1); + if (node >= O2NM_MAX_NODES) + break; + if (node == dlm->node_num) + continue; + + spin_unlock(&dlm->spinlock); + dlm_send_one_domain_exit(dlm, DLM_BEGIN_EXIT_DOMAIN_MSG, node); + spin_lock(&dlm->spinlock); + } + spin_unlock(&dlm->spinlock); +} + +static void dlm_leave_domain(struct dlm_ctxt *dlm) +{ + int node, clear_node, status; + + /* At this point we've migrated away all our locks and won't + * accept mastership of new ones. The dlm is responsible for + * almost nothing now. We make sure not to confuse any joining + * nodes and then commence shutdown procedure. */ + + spin_lock(&dlm->spinlock); + /* Clear ourselves from the domain map */ + clear_bit(dlm->node_num, dlm->domain_map); + while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, + 0)) < O2NM_MAX_NODES) { + /* Drop the dlm spinlock. This is safe wrt the domain_map. + * -nodes cannot be added now as the + * query_join_handlers knows to respond with OK_NO_MAP + * -we catch the right network errors if a node is + * removed from the map while we're sending him the + * exit message. */ + spin_unlock(&dlm->spinlock); + + clear_node = 1; + + status = dlm_send_one_domain_exit(dlm, DLM_EXIT_DOMAIN_MSG, + node); + if (status < 0 && + status != -ENOPROTOOPT && + status != -ENOTCONN) { + mlog(ML_NOTICE, "Error %d sending domain exit message " + "to node %d\n", status, node); + + /* Not sure what to do here but lets sleep for + * a bit in case this was a transient + * error... */ + msleep(DLM_DOMAIN_BACKOFF_MS); + clear_node = 0; + } + + spin_lock(&dlm->spinlock); + /* If we're not clearing the node bit then we intend + * to loop back around to try again. */ + if (clear_node) + clear_bit(node, dlm->domain_map); + } + spin_unlock(&dlm->spinlock); +} + +void dlm_unregister_domain(struct dlm_ctxt *dlm) +{ + int leave = 0; + struct dlm_lock_resource *res; + + spin_lock(&dlm_domain_lock); + BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED); + BUG_ON(!dlm->num_joins); + + dlm->num_joins--; + if (!dlm->num_joins) { + /* We mark it "in shutdown" now so new register + * requests wait until we've completely left the + * domain. Don't use DLM_CTXT_LEAVING yet as we still + * want new domain joins to communicate with us at + * least until we've completed migration of our + * resources. */ + dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN; + leave = 1; + } + spin_unlock(&dlm_domain_lock); + + if (leave) { + mlog(0, "shutting down domain %s\n", dlm->name); + dlm_begin_exit_domain(dlm); + + /* We changed dlm state, notify the thread */ + dlm_kick_thread(dlm, NULL); + + while (dlm_migrate_all_locks(dlm)) { + /* Give dlm_thread time to purge the lockres' */ + msleep(500); + mlog(0, "%s: more migration to do\n", dlm->name); + } + + /* This list should be empty. If not, print remaining lockres */ + if (!list_empty(&dlm->tracking_list)) { + mlog(ML_ERROR, "Following lockres' are still on the " + "tracking list:\n"); + list_for_each_entry(res, &dlm->tracking_list, tracking) + dlm_print_one_lock_resource(res); + } + + dlm_mark_domain_leaving(dlm); + dlm_leave_domain(dlm); + printk(KERN_NOTICE "o2dlm: Leaving domain %s\n", dlm->name); + dlm_force_free_mles(dlm); + dlm_complete_dlm_shutdown(dlm); + } + dlm_put(dlm); +} +EXPORT_SYMBOL_GPL(dlm_unregister_domain); + +static int dlm_query_join_proto_check(char *proto_type, int node, + struct dlm_protocol_version *ours, + struct dlm_protocol_version *request) +{ + int rc; + struct dlm_protocol_version proto = *request; + + if (!dlm_protocol_compare(ours, &proto)) { + mlog(0, + "node %u wanted to join with %s locking protocol " + "%u.%u, we respond with %u.%u\n", + node, proto_type, + request->pv_major, + request->pv_minor, + proto.pv_major, proto.pv_minor); + request->pv_minor = proto.pv_minor; + rc = 0; + } else { + mlog(ML_NOTICE, + "Node %u wanted to join with %s locking " + "protocol %u.%u, but we have %u.%u, disallowing\n", + node, proto_type, + request->pv_major, + request->pv_minor, + ours->pv_major, + ours->pv_minor); + rc = 1; + } + + return rc; +} + +/* + * struct dlm_query_join_packet is made up of four one-byte fields. They + * are effectively in big-endian order already. However, little-endian + * machines swap them before putting the packet on the wire (because + * query_join's response is a status, and that status is treated as a u32 + * on the wire). Thus, a big-endian and little-endian machines will treat + * this structure differently. + * + * The solution is to have little-endian machines swap the structure when + * converting from the structure to the u32 representation. This will + * result in the structure having the correct format on the wire no matter + * the host endian format. + */ +static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet, + u32 *wire) +{ + union dlm_query_join_response response; + + response.packet = *packet; + *wire = be32_to_cpu(response.intval); +} + +static void dlm_query_join_wire_to_packet(u32 wire, + struct dlm_query_join_packet *packet) +{ + union dlm_query_join_response response; + + response.intval = cpu_to_be32(wire); + *packet = response.packet; +} + +static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data) +{ + struct dlm_query_join_request *query; + struct dlm_query_join_packet packet = { + .code = JOIN_DISALLOW, + }; + struct dlm_ctxt *dlm = NULL; + u32 response; + u8 nodenum; + + query = (struct dlm_query_join_request *) msg->buf; + + mlog(0, "node %u wants to join domain %s\n", query->node_idx, + query->domain); + + /* + * If heartbeat doesn't consider the node live, tell it + * to back off and try again. This gives heartbeat a chance + * to catch up. + */ + if (!o2hb_check_node_heartbeating_no_sem(query->node_idx)) { + mlog(0, "node %u is not in our live map yet\n", + query->node_idx); + + packet.code = JOIN_DISALLOW; + goto respond; + } + + packet.code = JOIN_OK_NO_MAP; + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(query->domain, query->name_len); + if (!dlm) + goto unlock_respond; + + /* + * There is a small window where the joining node may not see the + * node(s) that just left but still part of the cluster. DISALLOW + * join request if joining node has different node map. + */ + nodenum=0; + while (nodenum < O2NM_MAX_NODES) { + if (test_bit(nodenum, dlm->domain_map)) { + if (!byte_test_bit(nodenum, query->node_map)) { + mlog(0, "disallow join as node %u does not " + "have node %u in its nodemap\n", + query->node_idx, nodenum); + packet.code = JOIN_DISALLOW; + goto unlock_respond; + } + } + nodenum++; + } + + /* Once the dlm ctxt is marked as leaving then we don't want + * to be put in someone's domain map. + * Also, explicitly disallow joining at certain troublesome + * times (ie. during recovery). */ + if (dlm->dlm_state != DLM_CTXT_LEAVING) { + int bit = query->node_idx; + spin_lock(&dlm->spinlock); + + if (dlm->dlm_state == DLM_CTXT_NEW && + dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) { + /*If this is a brand new context and we + * haven't started our join process yet, then + * the other node won the race. */ + packet.code = JOIN_OK_NO_MAP; + } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) { + /* Disallow parallel joins. */ + packet.code = JOIN_DISALLOW; + } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) { + mlog(0, "node %u trying to join, but recovery " + "is ongoing.\n", bit); + packet.code = JOIN_DISALLOW; + } else if (test_bit(bit, dlm->recovery_map)) { + mlog(0, "node %u trying to join, but it " + "still needs recovery.\n", bit); + packet.code = JOIN_DISALLOW; + } else if (test_bit(bit, dlm->domain_map)) { + mlog(0, "node %u trying to join, but it " + "is still in the domain! needs recovery?\n", + bit); + packet.code = JOIN_DISALLOW; + } else { + /* Alright we're fully a part of this domain + * so we keep some state as to who's joining + * and indicate to him that needs to be fixed + * up. */ + + /* Make sure we speak compatible locking protocols. */ + if (dlm_query_join_proto_check("DLM", bit, + &dlm->dlm_locking_proto, + &query->dlm_proto)) { + packet.code = JOIN_PROTOCOL_MISMATCH; + } else if (dlm_query_join_proto_check("fs", bit, + &dlm->fs_locking_proto, + &query->fs_proto)) { + packet.code = JOIN_PROTOCOL_MISMATCH; + } else { + packet.dlm_minor = query->dlm_proto.pv_minor; + packet.fs_minor = query->fs_proto.pv_minor; + packet.code = JOIN_OK; + __dlm_set_joining_node(dlm, query->node_idx); + } + } + + spin_unlock(&dlm->spinlock); + } +unlock_respond: + spin_unlock(&dlm_domain_lock); + +respond: + mlog(0, "We respond with %u\n", packet.code); + + dlm_query_join_packet_to_wire(&packet, &response); + return response; +} + +static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data) +{ + struct dlm_assert_joined *assert; + struct dlm_ctxt *dlm = NULL; + + assert = (struct dlm_assert_joined *) msg->buf; + + mlog(0, "node %u asserts join on domain %s\n", assert->node_idx, + assert->domain); + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len); + /* XXX should we consider no dlm ctxt an error? */ + if (dlm) { + spin_lock(&dlm->spinlock); + + /* Alright, this node has officially joined our + * domain. Set him in the map and clean up our + * leftover join state. */ + BUG_ON(dlm->joining_node != assert->node_idx); + + if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) { + mlog(0, "dlm recovery is ongoing, disallow join\n"); + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); + return -EAGAIN; + } + + set_bit(assert->node_idx, dlm->domain_map); + clear_bit(assert->node_idx, dlm->exit_domain_map); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + + printk(KERN_NOTICE "o2dlm: Node %u joins domain %s ", + assert->node_idx, dlm->name); + __dlm_print_nodes(dlm); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, assert->node_idx, 1); + + spin_unlock(&dlm->spinlock); + } + spin_unlock(&dlm_domain_lock); + + return 0; +} + +static int dlm_match_regions(struct dlm_ctxt *dlm, + struct dlm_query_region *qr, + char *local, int locallen) +{ + char *remote = qr->qr_regions; + char *l, *r; + int localnr, i, j, foundit; + int status = 0; + + if (!o2hb_global_heartbeat_active()) { + if (qr->qr_numregions) { + mlog(ML_ERROR, "Domain %s: Joining node %d has global " + "heartbeat enabled but local node %d does not\n", + qr->qr_domain, qr->qr_node, dlm->node_num); + status = -EINVAL; + } + goto bail; + } + + if (o2hb_global_heartbeat_active() && !qr->qr_numregions) { + mlog(ML_ERROR, "Domain %s: Local node %d has global " + "heartbeat enabled but joining node %d does not\n", + qr->qr_domain, dlm->node_num, qr->qr_node); + status = -EINVAL; + goto bail; + } + + r = remote; + for (i = 0; i < qr->qr_numregions; ++i) { + mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, r); + r += O2HB_MAX_REGION_NAME_LEN; + } + + localnr = min(O2NM_MAX_REGIONS, locallen/O2HB_MAX_REGION_NAME_LEN); + localnr = o2hb_get_all_regions(local, (u8)localnr); + + /* compare local regions with remote */ + l = local; + for (i = 0; i < localnr; ++i) { + foundit = 0; + r = remote; + for (j = 0; j <= qr->qr_numregions; ++j) { + if (!memcmp(l, r, O2HB_MAX_REGION_NAME_LEN)) { + foundit = 1; + break; + } + r += O2HB_MAX_REGION_NAME_LEN; + } + if (!foundit) { + status = -EINVAL; + mlog(ML_ERROR, "Domain %s: Region '%.*s' registered " + "in local node %d but not in joining node %d\n", + qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, l, + dlm->node_num, qr->qr_node); + goto bail; + } + l += O2HB_MAX_REGION_NAME_LEN; + } + + /* compare remote with local regions */ + r = remote; + for (i = 0; i < qr->qr_numregions; ++i) { + foundit = 0; + l = local; + for (j = 0; j < localnr; ++j) { + if (!memcmp(r, l, O2HB_MAX_REGION_NAME_LEN)) { + foundit = 1; + break; + } + l += O2HB_MAX_REGION_NAME_LEN; + } + if (!foundit) { + status = -EINVAL; + mlog(ML_ERROR, "Domain %s: Region '%.*s' registered " + "in joining node %d but not in local node %d\n", + qr->qr_domain, O2HB_MAX_REGION_NAME_LEN, r, + qr->qr_node, dlm->node_num); + goto bail; + } + r += O2HB_MAX_REGION_NAME_LEN; + } + +bail: + return status; +} + +static int dlm_send_regions(struct dlm_ctxt *dlm, unsigned long *node_map) +{ + struct dlm_query_region *qr = NULL; + int status, ret = 0, i; + char *p; + + if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES) + goto bail; + + qr = kzalloc(sizeof(struct dlm_query_region), GFP_KERNEL); + if (!qr) { + ret = -ENOMEM; + mlog_errno(ret); + goto bail; + } + + qr->qr_node = dlm->node_num; + qr->qr_namelen = strlen(dlm->name); + memcpy(qr->qr_domain, dlm->name, qr->qr_namelen); + /* if local hb, the numregions will be zero */ + if (o2hb_global_heartbeat_active()) + qr->qr_numregions = o2hb_get_all_regions(qr->qr_regions, + O2NM_MAX_REGIONS); + + p = qr->qr_regions; + for (i = 0; i < qr->qr_numregions; ++i, p += O2HB_MAX_REGION_NAME_LEN) + mlog(0, "Region %.*s\n", O2HB_MAX_REGION_NAME_LEN, p); + + i = -1; + while ((i = find_next_bit(node_map, O2NM_MAX_NODES, + i + 1)) < O2NM_MAX_NODES) { + if (i == dlm->node_num) + continue; + + mlog(0, "Sending regions to node %d\n", i); + + ret = o2net_send_message(DLM_QUERY_REGION, DLM_MOD_KEY, qr, + sizeof(struct dlm_query_region), + i, &status); + if (ret >= 0) + ret = status; + if (ret) { + mlog(ML_ERROR, "Region mismatch %d, node %d\n", + ret, i); + break; + } + } + +bail: + kfree(qr); + return ret; +} + +static int dlm_query_region_handler(struct o2net_msg *msg, u32 len, + void *data, void **ret_data) +{ + struct dlm_query_region *qr; + struct dlm_ctxt *dlm = NULL; + char *local = NULL; + int status = 0; + + qr = (struct dlm_query_region *) msg->buf; + + mlog(0, "Node %u queries hb regions on domain %s\n", qr->qr_node, + qr->qr_domain); + + /* buffer used in dlm_mast_regions() */ + local = kmalloc(sizeof(qr->qr_regions), GFP_KERNEL); + if (!local) + return -ENOMEM; + + status = -EINVAL; + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(qr->qr_domain, qr->qr_namelen); + if (!dlm) { + mlog(ML_ERROR, "Node %d queried hb regions on domain %s " + "before join domain\n", qr->qr_node, qr->qr_domain); + goto out_domain_lock; + } + + spin_lock(&dlm->spinlock); + if (dlm->joining_node != qr->qr_node) { + mlog(ML_ERROR, "Node %d queried hb regions on domain %s " + "but joining node is %d\n", qr->qr_node, qr->qr_domain, + dlm->joining_node); + goto out_dlm_lock; + } + + /* Support for global heartbeat was added in 1.1 */ + if (dlm->dlm_locking_proto.pv_major == 1 && + dlm->dlm_locking_proto.pv_minor == 0) { + mlog(ML_ERROR, "Node %d queried hb regions on domain %s " + "but active dlm protocol is %d.%d\n", qr->qr_node, + qr->qr_domain, dlm->dlm_locking_proto.pv_major, + dlm->dlm_locking_proto.pv_minor); + goto out_dlm_lock; + } + + status = dlm_match_regions(dlm, qr, local, sizeof(qr->qr_regions)); + +out_dlm_lock: + spin_unlock(&dlm->spinlock); + +out_domain_lock: + spin_unlock(&dlm_domain_lock); + + kfree(local); + + return status; +} + +static int dlm_match_nodes(struct dlm_ctxt *dlm, struct dlm_query_nodeinfo *qn) +{ + struct o2nm_node *local; + struct dlm_node_info *remote; + int i, j; + int status = 0; + + for (j = 0; j < qn->qn_numnodes; ++j) + mlog(0, "Node %3d, %pI4:%u\n", qn->qn_nodes[j].ni_nodenum, + &(qn->qn_nodes[j].ni_ipv4_address), + ntohs(qn->qn_nodes[j].ni_ipv4_port)); + + for (i = 0; i < O2NM_MAX_NODES && !status; ++i) { + local = o2nm_get_node_by_num(i); + remote = NULL; + for (j = 0; j < qn->qn_numnodes; ++j) { + if (qn->qn_nodes[j].ni_nodenum == i) { + remote = &(qn->qn_nodes[j]); + break; + } + } + + if (!local && !remote) + continue; + + if ((local && !remote) || (!local && remote)) + status = -EINVAL; + + if (!status && + ((remote->ni_nodenum != local->nd_num) || + (remote->ni_ipv4_port != local->nd_ipv4_port) || + (remote->ni_ipv4_address != local->nd_ipv4_address))) + status = -EINVAL; + + if (status) { + if (remote && !local) + mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) " + "registered in joining node %d but not in " + "local node %d\n", qn->qn_domain, + remote->ni_nodenum, + &(remote->ni_ipv4_address), + ntohs(remote->ni_ipv4_port), + qn->qn_nodenum, dlm->node_num); + if (local && !remote) + mlog(ML_ERROR, "Domain %s: Node %d (%pI4:%u) " + "registered in local node %d but not in " + "joining node %d\n", qn->qn_domain, + local->nd_num, &(local->nd_ipv4_address), + ntohs(local->nd_ipv4_port), + dlm->node_num, qn->qn_nodenum); + BUG_ON((!local && !remote)); + } + + if (local) + o2nm_node_put(local); + } + + return status; +} + +static int dlm_send_nodeinfo(struct dlm_ctxt *dlm, unsigned long *node_map) +{ + struct dlm_query_nodeinfo *qn = NULL; + struct o2nm_node *node; + int ret = 0, status, count, i; + + if (find_next_bit(node_map, O2NM_MAX_NODES, 0) >= O2NM_MAX_NODES) + goto bail; + + qn = kzalloc(sizeof(struct dlm_query_nodeinfo), GFP_KERNEL); + if (!qn) { + ret = -ENOMEM; + mlog_errno(ret); + goto bail; + } + + for (i = 0, count = 0; i < O2NM_MAX_NODES; ++i) { + node = o2nm_get_node_by_num(i); + if (!node) + continue; + qn->qn_nodes[count].ni_nodenum = node->nd_num; + qn->qn_nodes[count].ni_ipv4_port = node->nd_ipv4_port; + qn->qn_nodes[count].ni_ipv4_address = node->nd_ipv4_address; + mlog(0, "Node %3d, %pI4:%u\n", node->nd_num, + &(node->nd_ipv4_address), ntohs(node->nd_ipv4_port)); + ++count; + o2nm_node_put(node); + } + + qn->qn_nodenum = dlm->node_num; + qn->qn_numnodes = count; + qn->qn_namelen = strlen(dlm->name); + memcpy(qn->qn_domain, dlm->name, qn->qn_namelen); + + i = -1; + while ((i = find_next_bit(node_map, O2NM_MAX_NODES, + i + 1)) < O2NM_MAX_NODES) { + if (i == dlm->node_num) + continue; + + mlog(0, "Sending nodeinfo to node %d\n", i); + + ret = o2net_send_message(DLM_QUERY_NODEINFO, DLM_MOD_KEY, + qn, sizeof(struct dlm_query_nodeinfo), + i, &status); + if (ret >= 0) + ret = status; + if (ret) { + mlog(ML_ERROR, "node mismatch %d, node %d\n", ret, i); + break; + } + } + +bail: + kfree(qn); + return ret; +} + +static int dlm_query_nodeinfo_handler(struct o2net_msg *msg, u32 len, + void *data, void **ret_data) +{ + struct dlm_query_nodeinfo *qn; + struct dlm_ctxt *dlm = NULL; + int locked = 0, status = -EINVAL; + + qn = (struct dlm_query_nodeinfo *) msg->buf; + + mlog(0, "Node %u queries nodes on domain %s\n", qn->qn_nodenum, + qn->qn_domain); + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(qn->qn_domain, qn->qn_namelen); + if (!dlm) { + mlog(ML_ERROR, "Node %d queried nodes on domain %s before " + "join domain\n", qn->qn_nodenum, qn->qn_domain); + goto bail; + } + + spin_lock(&dlm->spinlock); + locked = 1; + if (dlm->joining_node != qn->qn_nodenum) { + mlog(ML_ERROR, "Node %d queried nodes on domain %s but " + "joining node is %d\n", qn->qn_nodenum, qn->qn_domain, + dlm->joining_node); + goto bail; + } + + /* Support for node query was added in 1.1 */ + if (dlm->dlm_locking_proto.pv_major == 1 && + dlm->dlm_locking_proto.pv_minor == 0) { + mlog(ML_ERROR, "Node %d queried nodes on domain %s " + "but active dlm protocol is %d.%d\n", qn->qn_nodenum, + qn->qn_domain, dlm->dlm_locking_proto.pv_major, + dlm->dlm_locking_proto.pv_minor); + goto bail; + } + + status = dlm_match_nodes(dlm, qn); + +bail: + if (locked) + spin_unlock(&dlm->spinlock); + spin_unlock(&dlm_domain_lock); + + return status; +} + +static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data, + void **ret_data) +{ + struct dlm_cancel_join *cancel; + struct dlm_ctxt *dlm = NULL; + + cancel = (struct dlm_cancel_join *) msg->buf; + + mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx, + cancel->domain); + + spin_lock(&dlm_domain_lock); + dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len); + + if (dlm) { + spin_lock(&dlm->spinlock); + + /* Yikes, this guy wants to cancel his join. No + * problem, we simply cleanup our join state. */ + BUG_ON(dlm->joining_node != cancel->node_idx); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + + spin_unlock(&dlm->spinlock); + } + spin_unlock(&dlm_domain_lock); + + return 0; +} + +static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm, + unsigned int node) +{ + int status; + struct dlm_cancel_join cancel_msg; + + memset(&cancel_msg, 0, sizeof(cancel_msg)); + cancel_msg.node_idx = dlm->node_num; + cancel_msg.name_len = strlen(dlm->name); + memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len); + + status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY, + &cancel_msg, sizeof(cancel_msg), node, + NULL); + if (status < 0) { + mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to " + "node %u\n", status, DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY, + node); + goto bail; + } + +bail: + return status; +} + +/* map_size should be in bytes. */ +static int dlm_send_join_cancels(struct dlm_ctxt *dlm, + unsigned long *node_map, + unsigned int map_size) +{ + int status, tmpstat; + int node; + + if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) * + sizeof(unsigned long))) { + mlog(ML_ERROR, + "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n", + map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES)); + return -EINVAL; + } + + status = 0; + node = -1; + while ((node = find_next_bit(node_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + tmpstat = dlm_send_one_join_cancel(dlm, node); + if (tmpstat) { + mlog(ML_ERROR, "Error return %d cancelling join on " + "node %d\n", tmpstat, node); + if (!status) + status = tmpstat; + } + } + + if (status) + mlog_errno(status); + return status; +} + +static int dlm_request_join(struct dlm_ctxt *dlm, + int node, + enum dlm_query_join_response_code *response) +{ + int status; + struct dlm_query_join_request join_msg; + struct dlm_query_join_packet packet; + u32 join_resp; + + mlog(0, "querying node %d\n", node); + + memset(&join_msg, 0, sizeof(join_msg)); + join_msg.node_idx = dlm->node_num; + join_msg.name_len = strlen(dlm->name); + memcpy(join_msg.domain, dlm->name, join_msg.name_len); + join_msg.dlm_proto = dlm->dlm_locking_proto; + join_msg.fs_proto = dlm->fs_locking_proto; + + /* copy live node map to join message */ + byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES); + + status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg, + sizeof(join_msg), node, &join_resp); + if (status < 0 && status != -ENOPROTOOPT) { + mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to " + "node %u\n", status, DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, + node); + goto bail; + } + dlm_query_join_wire_to_packet(join_resp, &packet); + + /* -ENOPROTOOPT from the net code means the other side isn't + listening for our message type -- that's fine, it means + his dlm isn't up, so we can consider him a 'yes' but not + joined into the domain. */ + if (status == -ENOPROTOOPT) { + status = 0; + *response = JOIN_OK_NO_MAP; + } else { + *response = packet.code; + switch (packet.code) { + case JOIN_DISALLOW: + case JOIN_OK_NO_MAP: + break; + case JOIN_PROTOCOL_MISMATCH: + mlog(ML_NOTICE, + "This node requested DLM locking protocol %u.%u and " + "filesystem locking protocol %u.%u. At least one of " + "the protocol versions on node %d is not compatible, " + "disconnecting\n", + dlm->dlm_locking_proto.pv_major, + dlm->dlm_locking_proto.pv_minor, + dlm->fs_locking_proto.pv_major, + dlm->fs_locking_proto.pv_minor, + node); + status = -EPROTO; + break; + case JOIN_OK: + /* Use the same locking protocol as the remote node */ + dlm->dlm_locking_proto.pv_minor = packet.dlm_minor; + dlm->fs_locking_proto.pv_minor = packet.fs_minor; + mlog(0, + "Node %d responds JOIN_OK with DLM locking protocol " + "%u.%u and fs locking protocol %u.%u\n", + node, + dlm->dlm_locking_proto.pv_major, + dlm->dlm_locking_proto.pv_minor, + dlm->fs_locking_proto.pv_major, + dlm->fs_locking_proto.pv_minor); + break; + default: + status = -EINVAL; + mlog(ML_ERROR, "invalid response %d from node %u\n", + packet.code, node); + /* Reset response to JOIN_DISALLOW */ + *response = JOIN_DISALLOW; + break; + } + } + + mlog(0, "status %d, node %d response is %d\n", status, node, + *response); + +bail: + return status; +} + +static int dlm_send_one_join_assert(struct dlm_ctxt *dlm, + unsigned int node) +{ + int status; + int ret; + struct dlm_assert_joined assert_msg; + + mlog(0, "Sending join assert to node %u\n", node); + + memset(&assert_msg, 0, sizeof(assert_msg)); + assert_msg.node_idx = dlm->node_num; + assert_msg.name_len = strlen(dlm->name); + memcpy(assert_msg.domain, dlm->name, assert_msg.name_len); + + status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY, + &assert_msg, sizeof(assert_msg), node, + &ret); + if (status < 0) + mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to " + "node %u\n", status, DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY, + node); + else + status = ret; + + return status; +} + +static void dlm_send_join_asserts(struct dlm_ctxt *dlm, + unsigned long *node_map) +{ + int status, node, live; + + status = 0; + node = -1; + while ((node = find_next_bit(node_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + do { + /* It is very important that this message be + * received so we spin until either the node + * has died or it gets the message. */ + status = dlm_send_one_join_assert(dlm, node); + + spin_lock(&dlm->spinlock); + live = test_bit(node, dlm->live_nodes_map); + spin_unlock(&dlm->spinlock); + + if (status) { + mlog(ML_ERROR, "Error return %d asserting " + "join on node %d\n", status, node); + + /* give us some time between errors... */ + if (live) + msleep(DLM_DOMAIN_BACKOFF_MS); + } + } while (status && live); + } +} + +struct domain_join_ctxt { + unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; + unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; +}; + +static int dlm_should_restart_join(struct dlm_ctxt *dlm, + struct domain_join_ctxt *ctxt, + enum dlm_query_join_response_code response) +{ + int ret; + + if (response == JOIN_DISALLOW) { + mlog(0, "Latest response of disallow -- should restart\n"); + return 1; + } + + spin_lock(&dlm->spinlock); + /* For now, we restart the process if the node maps have + * changed at all */ + ret = memcmp(ctxt->live_map, dlm->live_nodes_map, + sizeof(dlm->live_nodes_map)); + spin_unlock(&dlm->spinlock); + + if (ret) + mlog(0, "Node maps changed -- should restart\n"); + + return ret; +} + +static int dlm_try_to_join_domain(struct dlm_ctxt *dlm) +{ + int status = 0, tmpstat, node; + struct domain_join_ctxt *ctxt; + enum dlm_query_join_response_code response = JOIN_DISALLOW; + + mlog(0, "%p", dlm); + + ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL); + if (!ctxt) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + + /* group sem locking should work for us here -- we're already + * registered for heartbeat events so filling this should be + * atomic wrt getting those handlers called. */ + o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map)); + + spin_lock(&dlm->spinlock); + memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map)); + + __dlm_set_joining_node(dlm, dlm->node_num); + + spin_unlock(&dlm->spinlock); + + node = -1; + while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES, + node + 1)) < O2NM_MAX_NODES) { + if (node == dlm->node_num) + continue; + + status = dlm_request_join(dlm, node, &response); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + /* Ok, either we got a response or the node doesn't have a + * dlm up. */ + if (response == JOIN_OK) + set_bit(node, ctxt->yes_resp_map); + + if (dlm_should_restart_join(dlm, ctxt, response)) { + status = -EAGAIN; + goto bail; + } + } + + mlog(0, "Yay, done querying nodes!\n"); + + /* Yay, everyone agree's we can join the domain. My domain is + * comprised of all nodes who were put in the + * yes_resp_map. Copy that into our domain map and send a join + * assert message to clean up everyone elses state. */ + spin_lock(&dlm->spinlock); + memcpy(dlm->domain_map, ctxt->yes_resp_map, + sizeof(ctxt->yes_resp_map)); + set_bit(dlm->node_num, dlm->domain_map); + spin_unlock(&dlm->spinlock); + + /* Support for global heartbeat and node info was added in 1.1 */ + if (dlm->dlm_locking_proto.pv_major > 1 || + dlm->dlm_locking_proto.pv_minor > 0) { + status = dlm_send_nodeinfo(dlm, ctxt->yes_resp_map); + if (status) { + mlog_errno(status); + goto bail; + } + status = dlm_send_regions(dlm, ctxt->yes_resp_map); + if (status) { + mlog_errno(status); + goto bail; + } + } + + dlm_send_join_asserts(dlm, ctxt->yes_resp_map); + + /* Joined state *must* be set before the joining node + * information, otherwise the query_join handler may read no + * current joiner but a state of NEW and tell joining nodes + * we're not in the domain. */ + spin_lock(&dlm_domain_lock); + dlm->dlm_state = DLM_CTXT_JOINED; + dlm->num_joins++; + spin_unlock(&dlm_domain_lock); + +bail: + spin_lock(&dlm->spinlock); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + if (!status) { + printk(KERN_NOTICE "o2dlm: Joining domain %s ", dlm->name); + __dlm_print_nodes(dlm); + } + spin_unlock(&dlm->spinlock); + + if (ctxt) { + /* Do we need to send a cancel message to any nodes? */ + if (status < 0) { + tmpstat = dlm_send_join_cancels(dlm, + ctxt->yes_resp_map, + sizeof(ctxt->yes_resp_map)); + if (tmpstat < 0) + mlog_errno(tmpstat); + } + kfree(ctxt); + } + + mlog(0, "returning %d\n", status); + return status; +} + +static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm) +{ + o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_up); + o2hb_unregister_callback(dlm->name, &dlm->dlm_hb_down); + o2net_unregister_handler_list(&dlm->dlm_domain_handlers); +} + +static int dlm_register_domain_handlers(struct dlm_ctxt *dlm) +{ + int status; + + mlog(0, "registering handlers.\n"); + + o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB, + dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI); + o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB, + dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI); + + status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down); + if (status) + goto bail; + + status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key, + sizeof(struct dlm_master_request), + dlm_master_request_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key, + sizeof(struct dlm_assert_master), + dlm_assert_master_handler, + dlm, dlm_assert_master_post_handler, + &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key, + sizeof(struct dlm_create_lock), + dlm_create_lock_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key, + DLM_CONVERT_LOCK_MAX_LEN, + dlm_convert_lock_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key, + DLM_UNLOCK_LOCK_MAX_LEN, + dlm_unlock_lock_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key, + DLM_PROXY_AST_MAX_LEN, + dlm_proxy_ast_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key, + sizeof(struct dlm_exit_domain), + dlm_exit_domain_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_DEREF_LOCKRES_MSG, dlm->key, + sizeof(struct dlm_deref_lockres), + dlm_deref_lockres_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key, + sizeof(struct dlm_migrate_request), + dlm_migrate_request_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key, + DLM_MIG_LOCKRES_MAX_LEN, + dlm_mig_lockres_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key, + sizeof(struct dlm_master_requery), + dlm_master_requery_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key, + sizeof(struct dlm_lock_request), + dlm_request_all_locks_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key, + sizeof(struct dlm_reco_data_done), + dlm_reco_data_done_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key, + sizeof(struct dlm_begin_reco), + dlm_begin_reco_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key, + sizeof(struct dlm_finalize_reco), + dlm_finalize_reco_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_BEGIN_EXIT_DOMAIN_MSG, dlm->key, + sizeof(struct dlm_exit_domain), + dlm_begin_exit_domain_handler, + dlm, NULL, &dlm->dlm_domain_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_DEREF_LOCKRES_DONE, dlm->key, + sizeof(struct dlm_deref_lockres_done), + dlm_deref_lockres_done_handler, + dlm, NULL, &dlm->dlm_domain_handlers); +bail: + if (status) + dlm_unregister_domain_handlers(dlm); + + return status; +} + +static int dlm_join_domain(struct dlm_ctxt *dlm) +{ + int status; + unsigned int backoff; + unsigned int total_backoff = 0; + char wq_name[O2NM_MAX_NAME_LEN]; + + BUG_ON(!dlm); + + mlog(0, "Join domain %s\n", dlm->name); + + status = dlm_register_domain_handlers(dlm); + if (status) { + mlog_errno(status); + goto bail; + } + + status = dlm_launch_thread(dlm); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = dlm_launch_recovery_thread(dlm); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = dlm_debug_init(dlm); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + snprintf(wq_name, O2NM_MAX_NAME_LEN, "dlm_wq-%s", dlm->name); + dlm->dlm_worker = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 0); + if (!dlm->dlm_worker) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + + do { + status = dlm_try_to_join_domain(dlm); + + /* If we're racing another node to the join, then we + * need to back off temporarily and let them + * complete. */ +#define DLM_JOIN_TIMEOUT_MSECS 90000 + if (status == -EAGAIN) { + if (signal_pending(current)) { + status = -ERESTARTSYS; + goto bail; + } + + if (total_backoff > DLM_JOIN_TIMEOUT_MSECS) { + status = -ERESTARTSYS; + mlog(ML_NOTICE, "Timed out joining dlm domain " + "%s after %u msecs\n", dlm->name, + total_backoff); + goto bail; + } + + /* + * <chip> After you! + * <dale> No, after you! + * <chip> I insist! + * <dale> But you first! + * ... + */ + backoff = (unsigned int)(jiffies & 0x3); + backoff *= DLM_DOMAIN_BACKOFF_MS; + total_backoff += backoff; + mlog(0, "backoff %d\n", backoff); + msleep(backoff); + } + } while (status == -EAGAIN); + + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = 0; +bail: + wake_up(&dlm_domain_events); + + if (status) { + dlm_unregister_domain_handlers(dlm); + dlm_debug_shutdown(dlm); + dlm_complete_thread(dlm); + dlm_complete_recovery_thread(dlm); + dlm_destroy_dlm_worker(dlm); + } + + return status; +} + +static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain, + u32 key) +{ + int i; + int ret; + struct dlm_ctxt *dlm = NULL; + + dlm = kzalloc(sizeof(*dlm), GFP_KERNEL); + if (!dlm) { + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + dlm->name = kstrdup(domain, GFP_KERNEL); + if (dlm->name == NULL) { + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES); + if (!dlm->lockres_hash) { + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + for (i = 0; i < DLM_HASH_BUCKETS; i++) + INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i)); + + dlm->master_hash = (struct hlist_head **) + dlm_alloc_pagevec(DLM_HASH_PAGES); + if (!dlm->master_hash) { + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + for (i = 0; i < DLM_HASH_BUCKETS; i++) + INIT_HLIST_HEAD(dlm_master_hash(dlm, i)); + + dlm->key = key; + dlm->node_num = o2nm_this_node(); + + ret = dlm_create_debugfs_subroot(dlm); + if (ret < 0) + goto leave; + + spin_lock_init(&dlm->spinlock); + spin_lock_init(&dlm->master_lock); + spin_lock_init(&dlm->ast_lock); + spin_lock_init(&dlm->track_lock); + INIT_LIST_HEAD(&dlm->list); + INIT_LIST_HEAD(&dlm->dirty_list); + INIT_LIST_HEAD(&dlm->reco.resources); + INIT_LIST_HEAD(&dlm->reco.node_data); + INIT_LIST_HEAD(&dlm->purge_list); + INIT_LIST_HEAD(&dlm->dlm_domain_handlers); + INIT_LIST_HEAD(&dlm->tracking_list); + dlm->reco.state = 0; + + INIT_LIST_HEAD(&dlm->pending_asts); + INIT_LIST_HEAD(&dlm->pending_basts); + + mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n", + dlm->recovery_map, &(dlm->recovery_map[0])); + + memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map)); + memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map)); + memset(dlm->domain_map, 0, sizeof(dlm->domain_map)); + + dlm->dlm_thread_task = NULL; + dlm->dlm_reco_thread_task = NULL; + dlm->dlm_worker = NULL; + init_waitqueue_head(&dlm->dlm_thread_wq); + init_waitqueue_head(&dlm->dlm_reco_thread_wq); + init_waitqueue_head(&dlm->reco.event); + init_waitqueue_head(&dlm->ast_wq); + init_waitqueue_head(&dlm->migration_wq); + INIT_LIST_HEAD(&dlm->mle_hb_events); + + dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN; + init_waitqueue_head(&dlm->dlm_join_events); + + dlm->migrate_done = 0; + + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + + atomic_set(&dlm->res_tot_count, 0); + atomic_set(&dlm->res_cur_count, 0); + for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) { + atomic_set(&dlm->mle_tot_count[i], 0); + atomic_set(&dlm->mle_cur_count[i], 0); + } + + spin_lock_init(&dlm->work_lock); + INIT_LIST_HEAD(&dlm->work_list); + INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work); + + kref_init(&dlm->dlm_refs); + dlm->dlm_state = DLM_CTXT_NEW; + + INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks); + + mlog(0, "context init: refcount %u\n", + kref_read(&dlm->dlm_refs)); + +leave: + if (ret < 0 && dlm) { + if (dlm->master_hash) + dlm_free_pagevec((void **)dlm->master_hash, + DLM_HASH_PAGES); + + if (dlm->lockres_hash) + dlm_free_pagevec((void **)dlm->lockres_hash, + DLM_HASH_PAGES); + + kfree(dlm->name); + kfree(dlm); + dlm = NULL; + } + return dlm; +} + +/* + * Compare a requested locking protocol version against the current one. + * + * If the major numbers are different, they are incompatible. + * If the current minor is greater than the request, they are incompatible. + * If the current minor is less than or equal to the request, they are + * compatible, and the requester should run at the current minor version. + */ +static int dlm_protocol_compare(struct dlm_protocol_version *existing, + struct dlm_protocol_version *request) +{ + if (existing->pv_major != request->pv_major) + return 1; + + if (existing->pv_minor > request->pv_minor) + return 1; + + if (existing->pv_minor < request->pv_minor) + request->pv_minor = existing->pv_minor; + + return 0; +} + +/* + * dlm_register_domain: one-time setup per "domain". + * + * The filesystem passes in the requested locking version via proto. + * If registration was successful, proto will contain the negotiated + * locking protocol. + */ +struct dlm_ctxt * dlm_register_domain(const char *domain, + u32 key, + struct dlm_protocol_version *fs_proto) +{ + int ret; + struct dlm_ctxt *dlm = NULL; + struct dlm_ctxt *new_ctxt = NULL; + + if (strlen(domain) >= O2NM_MAX_NAME_LEN) { + ret = -ENAMETOOLONG; + mlog(ML_ERROR, "domain name length too long\n"); + goto leave; + } + + mlog(0, "register called for domain \"%s\"\n", domain); + +retry: + dlm = NULL; + if (signal_pending(current)) { + ret = -ERESTARTSYS; + mlog_errno(ret); + goto leave; + } + + spin_lock(&dlm_domain_lock); + + dlm = __dlm_lookup_domain(domain); + if (dlm) { + if (dlm->dlm_state != DLM_CTXT_JOINED) { + spin_unlock(&dlm_domain_lock); + + mlog(0, "This ctxt is not joined yet!\n"); + wait_event_interruptible(dlm_domain_events, + dlm_wait_on_domain_helper( + domain)); + goto retry; + } + + if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) { + spin_unlock(&dlm_domain_lock); + mlog(ML_ERROR, + "Requested locking protocol version is not " + "compatible with already registered domain " + "\"%s\"\n", domain); + ret = -EPROTO; + goto leave; + } + + __dlm_get(dlm); + dlm->num_joins++; + + spin_unlock(&dlm_domain_lock); + + ret = 0; + goto leave; + } + + /* doesn't exist */ + if (!new_ctxt) { + spin_unlock(&dlm_domain_lock); + + new_ctxt = dlm_alloc_ctxt(domain, key); + if (new_ctxt) + goto retry; + + ret = -ENOMEM; + mlog_errno(ret); + goto leave; + } + + /* a little variable switch-a-roo here... */ + dlm = new_ctxt; + new_ctxt = NULL; + + /* add the new domain */ + list_add_tail(&dlm->list, &dlm_domains); + spin_unlock(&dlm_domain_lock); + + /* + * Pass the locking protocol version into the join. If the join + * succeeds, it will have the negotiated protocol set. + */ + dlm->dlm_locking_proto = dlm_protocol; + dlm->fs_locking_proto = *fs_proto; + + ret = dlm_join_domain(dlm); + if (ret) { + mlog_errno(ret); + dlm_put(dlm); + goto leave; + } + + /* Tell the caller what locking protocol we negotiated */ + *fs_proto = dlm->fs_locking_proto; + + ret = 0; +leave: + if (new_ctxt) + dlm_free_ctxt_mem(new_ctxt); + + if (ret < 0) + dlm = ERR_PTR(ret); + + return dlm; +} +EXPORT_SYMBOL_GPL(dlm_register_domain); + +static LIST_HEAD(dlm_join_handlers); + +static void dlm_unregister_net_handlers(void) +{ + o2net_unregister_handler_list(&dlm_join_handlers); +} + +static int dlm_register_net_handlers(void) +{ + int status = 0; + + status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, + sizeof(struct dlm_query_join_request), + dlm_query_join_handler, + NULL, NULL, &dlm_join_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY, + sizeof(struct dlm_assert_joined), + dlm_assert_joined_handler, + NULL, NULL, &dlm_join_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY, + sizeof(struct dlm_cancel_join), + dlm_cancel_join_handler, + NULL, NULL, &dlm_join_handlers); + if (status) + goto bail; + + status = o2net_register_handler(DLM_QUERY_REGION, DLM_MOD_KEY, + sizeof(struct dlm_query_region), + dlm_query_region_handler, + NULL, NULL, &dlm_join_handlers); + + if (status) + goto bail; + + status = o2net_register_handler(DLM_QUERY_NODEINFO, DLM_MOD_KEY, + sizeof(struct dlm_query_nodeinfo), + dlm_query_nodeinfo_handler, + NULL, NULL, &dlm_join_handlers); +bail: + if (status < 0) + dlm_unregister_net_handlers(); + + return status; +} + +/* Domain eviction callback handling. + * + * The file system requires notification of node death *before* the + * dlm completes it's recovery work, otherwise it may be able to + * acquire locks on resources requiring recovery. Since the dlm can + * evict a node from it's domain *before* heartbeat fires, a similar + * mechanism is required. */ + +/* Eviction is not expected to happen often, so a per-domain lock is + * not necessary. Eviction callbacks are allowed to sleep for short + * periods of time. */ +static DECLARE_RWSEM(dlm_callback_sem); + +void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm, + int node_num) +{ + struct dlm_eviction_cb *cb; + + down_read(&dlm_callback_sem); + list_for_each_entry(cb, &dlm->dlm_eviction_callbacks, ec_item) { + cb->ec_func(node_num, cb->ec_data); + } + up_read(&dlm_callback_sem); +} + +void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb, + dlm_eviction_func *f, + void *data) +{ + INIT_LIST_HEAD(&cb->ec_item); + cb->ec_func = f; + cb->ec_data = data; +} +EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb); + +void dlm_register_eviction_cb(struct dlm_ctxt *dlm, + struct dlm_eviction_cb *cb) +{ + down_write(&dlm_callback_sem); + list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks); + up_write(&dlm_callback_sem); +} +EXPORT_SYMBOL_GPL(dlm_register_eviction_cb); + +void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb) +{ + down_write(&dlm_callback_sem); + list_del_init(&cb->ec_item); + up_write(&dlm_callback_sem); +} +EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb); + +static int __init dlm_init(void) +{ + int status; + + status = dlm_init_mle_cache(); + if (status) { + mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n"); + goto error; + } + + status = dlm_init_master_caches(); + if (status) { + mlog(ML_ERROR, "Could not create o2dlm_lockres and " + "o2dlm_lockname slabcaches\n"); + goto error; + } + + status = dlm_init_lock_cache(); + if (status) { + mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n"); + goto error; + } + + status = dlm_register_net_handlers(); + if (status) { + mlog(ML_ERROR, "Unable to register network handlers\n"); + goto error; + } + + status = dlm_create_debugfs_root(); + if (status) + goto error; + + return 0; +error: + dlm_unregister_net_handlers(); + dlm_destroy_lock_cache(); + dlm_destroy_master_caches(); + dlm_destroy_mle_cache(); + return -1; +} + +static void __exit dlm_exit (void) +{ + dlm_destroy_debugfs_root(); + dlm_unregister_net_handlers(); + dlm_destroy_lock_cache(); + dlm_destroy_master_caches(); + dlm_destroy_mle_cache(); +} + +MODULE_AUTHOR("Oracle"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("OCFS2 Distributed Lock Management"); + +module_init(dlm_init); +module_exit(dlm_exit); |