| /* -*- 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/utsname.h> |
| #include <linux/init.h> |
| #include <linux/spinlock.h> |
| #include <linux/delay.h> |
| #include <linux/err.h> |
| |
| #include "cluster/heartbeat.h" |
| #include "cluster/nodemanager.h" |
| #include "cluster/tcp.h" |
| |
| #include "dlmapi.h" |
| #include "dlmcommon.h" |
| |
| #include "dlmdebug.h" |
| #include "dlmdomain.h" |
| |
| #include "dlmver.h" |
| |
| #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN) |
| #include "cluster/masklog.h" |
| |
| 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(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; |
| 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 |
| * |
| */ |
| |
| spinlock_t dlm_domain_lock = SPIN_LOCK_UNLOCKED; |
| LIST_HEAD(dlm_domains); |
| static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events); |
| |
| #define DLM_DOMAIN_BACKOFF_MS 200 |
| |
| static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data); |
| static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data); |
| static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data); |
| static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data); |
| |
| static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm); |
| |
| void __dlm_unhash_lockres(struct dlm_lock_resource *lockres) |
| { |
| hlist_del_init(&lockres->hash_node); |
| dlm_lockres_put(lockres); |
| } |
| |
| void __dlm_insert_lockres(struct dlm_ctxt *dlm, |
| struct dlm_lock_resource *res) |
| { |
| struct hlist_head *bucket; |
| struct qstr *q; |
| |
| assert_spin_locked(&dlm->spinlock); |
| |
| q = &res->lockname; |
| bucket = dlm_lockres_hash(dlm, q->hash); |
| |
| /* get a reference for our hashtable */ |
| dlm_lockres_get(res); |
| |
| hlist_add_head(&res->hash_node, bucket); |
| } |
| |
| struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm, |
| const char *name, |
| unsigned int len, |
| unsigned int hash) |
| { |
| struct hlist_head *bucket; |
| struct hlist_node *list; |
| |
| mlog_entry("%.*s\n", len, name); |
| |
| assert_spin_locked(&dlm->spinlock); |
| |
| bucket = dlm_lockres_hash(dlm, hash); |
| |
| hlist_for_each(list, bucket) { |
| struct dlm_lock_resource *res = hlist_entry(list, |
| struct dlm_lock_resource, 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; |
| } |
| |
| 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 = NULL; |
| struct list_head *iter; |
| |
| assert_spin_locked(&dlm_domain_lock); |
| |
| /* tmp->name here is always NULL terminated, |
| * but domain may not be! */ |
| list_for_each(iter, &dlm_domains) { |
| tmp = list_entry (iter, struct dlm_ctxt, list); |
| if (strlen(tmp->name) == len && |
| memcmp(tmp->name, domain, len)==0) |
| break; |
| tmp = NULL; |
| } |
| |
| return tmp; |
| } |
| |
| /* 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) |
| { |
| if (dlm->lockres_hash) |
| dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES); |
| |
| if (dlm->name) |
| 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 list_head *iter; |
| struct dlm_ctxt *target = NULL; |
| |
| spin_lock(&dlm_domain_lock); |
| |
| list_for_each(iter, &dlm_domains) { |
| target = list_entry (iter, struct dlm_ctxt, list); |
| |
| if (target == dlm) { |
| __dlm_get(target); |
| break; |
| } |
| |
| target = NULL; |
| } |
| |
| spin_unlock(&dlm_domain_lock); |
| |
| return target; |
| } |
| |
| 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_complete_dlm_shutdown(struct dlm_ctxt *dlm) |
| { |
| dlm_unregister_domain_handlers(dlm); |
| dlm_complete_thread(dlm); |
| dlm_complete_recovery_thread(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 void dlm_migrate_all_locks(struct dlm_ctxt *dlm) |
| { |
| int i; |
| struct dlm_lock_resource *res; |
| |
| mlog(0, "Migrating locks from domain %s\n", dlm->name); |
| restart: |
| spin_lock(&dlm->spinlock); |
| for (i = 0; i < DLM_HASH_BUCKETS; i++) { |
| while (!hlist_empty(dlm_lockres_hash(dlm, i))) { |
| res = hlist_entry(dlm_lockres_hash(dlm, i)->first, |
| struct dlm_lock_resource, hash_node); |
| /* need reference when manually grabbing lockres */ |
| dlm_lockres_get(res); |
| /* this should unhash the lockres |
| * and exit with dlm->spinlock */ |
| mlog(0, "purging res=%p\n", res); |
| if (dlm_lockres_is_dirty(dlm, res)) { |
| /* HACK! this should absolutely go. |
| * need to figure out why some empty |
| * lockreses are still marked dirty */ |
| mlog(ML_ERROR, "lockres %.*s dirty!\n", |
| res->lockname.len, res->lockname.name); |
| |
| spin_unlock(&dlm->spinlock); |
| dlm_kick_thread(dlm, res); |
| wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res)); |
| dlm_lockres_put(res); |
| goto restart; |
| } |
| dlm_purge_lockres(dlm, res); |
| dlm_lockres_put(res); |
| } |
| } |
| spin_unlock(&dlm->spinlock); |
| |
| mlog(0, "DONE Migrating locks from domain %s\n", dlm->name); |
| } |
| |
| 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 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; |
| |
| assert_spin_locked(&dlm->spinlock); |
| |
| mlog(ML_NOTICE, "Nodes in my domain (\"%s\"):\n", dlm->name); |
| |
| while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES, |
| node + 1)) < O2NM_MAX_NODES) { |
| mlog(ML_NOTICE, " node %d\n", node); |
| } |
| } |
| |
| static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data) |
| { |
| struct dlm_ctxt *dlm = data; |
| unsigned int node; |
| struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf; |
| |
| mlog_entry("%p %u %p", msg, len, data); |
| |
| if (!dlm_grab(dlm)) |
| return 0; |
| |
| node = exit_msg->node_idx; |
| |
| mlog(0, "Node %u leaves domain %s\n", node, dlm->name); |
| |
| spin_lock(&dlm->spinlock); |
| clear_bit(node, dlm->domain_map); |
| __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, |
| unsigned int node) |
| { |
| int status; |
| struct dlm_exit_domain leave_msg; |
| |
| mlog(0, "Asking node %u if we can leave the domain %s me = %u\n", |
| node, dlm->name, dlm->node_num); |
| |
| memset(&leave_msg, 0, sizeof(leave_msg)); |
| leave_msg.node_idx = dlm->node_num; |
| |
| status = o2net_send_message(DLM_EXIT_DOMAIN_MSG, dlm->key, |
| &leave_msg, sizeof(leave_msg), node, |
| NULL); |
| |
| mlog(0, "status return %d from o2net_send_message\n", status); |
| |
| return status; |
| } |
| |
| |
| 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, 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); |
| } |
| |
| int dlm_joined(struct dlm_ctxt *dlm) |
| { |
| int ret = 0; |
| |
| spin_lock(&dlm_domain_lock); |
| |
| if (dlm->dlm_state == DLM_CTXT_JOINED) |
| ret = 1; |
| |
| spin_unlock(&dlm_domain_lock); |
| |
| return ret; |
| } |
| |
| int dlm_shutting_down(struct dlm_ctxt *dlm) |
| { |
| int ret = 0; |
| |
| spin_lock(&dlm_domain_lock); |
| |
| if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN) |
| ret = 1; |
| |
| spin_unlock(&dlm_domain_lock); |
| |
| return ret; |
| } |
| |
| void dlm_unregister_domain(struct dlm_ctxt *dlm) |
| { |
| int leave = 0; |
| |
| 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); |
| |
| /* We changed dlm state, notify the thread */ |
| dlm_kick_thread(dlm, NULL); |
| |
| dlm_migrate_all_locks(dlm); |
| dlm_mark_domain_leaving(dlm); |
| dlm_leave_domain(dlm); |
| dlm_complete_dlm_shutdown(dlm); |
| } |
| dlm_put(dlm); |
| } |
| EXPORT_SYMBOL_GPL(dlm_unregister_domain); |
| |
| static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data) |
| { |
| struct dlm_query_join_request *query; |
| enum dlm_query_join_response response; |
| struct dlm_ctxt *dlm = NULL; |
| |
| 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(query->node_idx)) { |
| mlog(0, "node %u is not in our live map yet\n", |
| query->node_idx); |
| |
| response = JOIN_DISALLOW; |
| goto respond; |
| } |
| |
| response = JOIN_OK_NO_MAP; |
| |
| spin_lock(&dlm_domain_lock); |
| dlm = __dlm_lookup_domain_full(query->domain, query->name_len); |
| /* 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->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. */ |
| response = JOIN_OK_NO_MAP; |
| } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) { |
| /* Disallow parallel joins. */ |
| response = JOIN_DISALLOW; |
| } else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) { |
| mlog(ML_NOTICE, "node %u trying to join, but recovery " |
| "is ongoing.\n", bit); |
| response = JOIN_DISALLOW; |
| } else if (test_bit(bit, dlm->recovery_map)) { |
| mlog(ML_NOTICE, "node %u trying to join, but it " |
| "still needs recovery.\n", bit); |
| response = JOIN_DISALLOW; |
| } else if (test_bit(bit, dlm->domain_map)) { |
| mlog(ML_NOTICE, "node %u trying to join, but it " |
| "is still in the domain! needs recovery?\n", |
| bit); |
| response = 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. */ |
| response = JOIN_OK; |
| __dlm_set_joining_node(dlm, query->node_idx); |
| } |
| |
| spin_unlock(&dlm->spinlock); |
| } |
| spin_unlock(&dlm_domain_lock); |
| |
| respond: |
| mlog(0, "We respond with %u\n", response); |
| |
| return response; |
| } |
| |
| static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *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); |
| set_bit(assert->node_idx, dlm->domain_map); |
| __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); |
| |
| __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_cancel_join_handler(struct o2net_msg *msg, u32 len, void *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_errno(status); |
| 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; |
| unsigned 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, 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 *response) |
| { |
| int status, retval; |
| struct dlm_query_join_request join_msg; |
| |
| 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); |
| |
| status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg, |
| sizeof(join_msg), node, &retval); |
| if (status < 0 && status != -ENOPROTOOPT) { |
| mlog_errno(status); |
| goto bail; |
| } |
| |
| /* -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 if (retval == JOIN_DISALLOW || |
| retval == JOIN_OK || |
| retval == JOIN_OK_NO_MAP) { |
| *response = retval; |
| } else { |
| status = -EINVAL; |
| mlog(ML_ERROR, "invalid response %d from node %u\n", retval, |
| node); |
| } |
| |
| 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; |
| 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, |
| NULL); |
| if (status < 0) |
| mlog_errno(status); |
| |
| 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 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 response; |
| |
| mlog_entry("%p", dlm); |
| |
| ctxt = kcalloc(1, 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); |
| |
| 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) |
| __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->dlm_hb_up); |
| o2hb_unregister_callback(&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); |
| status = o2hb_register_callback(&dlm->dlm_hb_down); |
| if (status) |
| goto bail; |
| |
| 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->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, &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->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, &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, &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, &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, &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, &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, &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, &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, &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, &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, &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, &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, &dlm->dlm_domain_handlers); |
| if (status) |
| goto bail; |
| |
| bail: |
| if (status) |
| dlm_unregister_domain_handlers(dlm); |
| |
| return status; |
| } |
| |
| static int dlm_join_domain(struct dlm_ctxt *dlm) |
| { |
| int status; |
| |
| 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; |
| } |
| |
| do { |
| unsigned int backoff; |
| 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. */ |
| if (status == -EAGAIN) { |
| if (signal_pending(current)) { |
| status = -ERESTARTSYS; |
| 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; |
| 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_complete_thread(dlm); |
| dlm_complete_recovery_thread(dlm); |
| } |
| |
| return status; |
| } |
| |
| static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain, |
| u32 key) |
| { |
| int i; |
| struct dlm_ctxt *dlm = NULL; |
| |
| dlm = kcalloc(1, sizeof(*dlm), GFP_KERNEL); |
| if (!dlm) { |
| mlog_errno(-ENOMEM); |
| goto leave; |
| } |
| |
| dlm->name = kmalloc(strlen(domain) + 1, GFP_KERNEL); |
| if (dlm->name == NULL) { |
| mlog_errno(-ENOMEM); |
| kfree(dlm); |
| dlm = NULL; |
| goto leave; |
| } |
| |
| dlm->lockres_hash = (struct hlist_head **)dlm_alloc_pagevec(DLM_HASH_PAGES); |
| if (!dlm->lockres_hash) { |
| mlog_errno(-ENOMEM); |
| kfree(dlm->name); |
| kfree(dlm); |
| dlm = NULL; |
| goto leave; |
| } |
| |
| for (i = 0; i < DLM_HASH_BUCKETS; i++) |
| INIT_HLIST_HEAD(dlm_lockres_hash(dlm, i)); |
| |
| strcpy(dlm->name, domain); |
| dlm->key = key; |
| dlm->node_num = o2nm_this_node(); |
| |
| spin_lock_init(&dlm->spinlock); |
| spin_lock_init(&dlm->master_lock); |
| spin_lock_init(&dlm->ast_lock); |
| INIT_LIST_HEAD(&dlm->list); |
| INIT_LIST_HEAD(&dlm->dirty_list); |
| INIT_LIST_HEAD(&dlm->reco.resources); |
| INIT_LIST_HEAD(&dlm->reco.received); |
| INIT_LIST_HEAD(&dlm->reco.node_data); |
| INIT_LIST_HEAD(&dlm->purge_list); |
| INIT_LIST_HEAD(&dlm->dlm_domain_handlers); |
| 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; |
| 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->master_list); |
| INIT_LIST_HEAD(&dlm->mle_hb_events); |
| |
| dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN; |
| init_waitqueue_head(&dlm->dlm_join_events); |
| |
| dlm->reco.new_master = O2NM_INVALID_NODE_NUM; |
| dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; |
| atomic_set(&dlm->local_resources, 0); |
| atomic_set(&dlm->remote_resources, 0); |
| atomic_set(&dlm->unknown_resources, 0); |
| |
| spin_lock_init(&dlm->work_lock); |
| INIT_LIST_HEAD(&dlm->work_list); |
| INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work, dlm); |
| |
| 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", |
| atomic_read(&dlm->dlm_refs.refcount)); |
| |
| leave: |
| return dlm; |
| } |
| |
| /* |
| * dlm_register_domain: one-time setup per "domain" |
| */ |
| struct dlm_ctxt * dlm_register_domain(const char *domain, |
| u32 key) |
| { |
| 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; |
| } |
| |
| if (!o2hb_check_local_node_heartbeating()) { |
| mlog(ML_ERROR, "the local node has not been configured, or is " |
| "not heartbeating\n"); |
| ret = -EPROTO; |
| 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; |
| } |
| |
| __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); |
| |
| ret = dlm_join_domain(dlm); |
| if (ret) { |
| mlog_errno(ret); |
| dlm_put(dlm); |
| goto leave; |
| } |
| |
| 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, &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, &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, &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 list_head *iter; |
| struct dlm_eviction_cb *cb; |
| |
| down_read(&dlm_callback_sem); |
| list_for_each(iter, &dlm->dlm_eviction_callbacks) { |
| cb = list_entry(iter, struct dlm_eviction_cb, 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; |
| |
| dlm_print_version(); |
| |
| status = dlm_init_mle_cache(); |
| if (status) |
| return -1; |
| |
| status = dlm_register_net_handlers(); |
| if (status) { |
| dlm_destroy_mle_cache(); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static void __exit dlm_exit (void) |
| { |
| dlm_unregister_net_handlers(); |
| dlm_destroy_mle_cache(); |
| } |
| |
| MODULE_AUTHOR("Oracle"); |
| MODULE_LICENSE("GPL"); |
| |
| module_init(dlm_init); |
| module_exit(dlm_exit); |