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-rw-r--r--fs/ocfs2/dlm/dlmdomain.c2365
1 files changed, 2365 insertions, 0 deletions
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
new file mode 100644
index 000000000..c4eccd499
--- /dev/null
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -0,0 +1,2365 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * dlmdomain.c
+ *
+ * defines domain join / leave apis
+ *
+ * Copyright (C) 2004 Oracle. All rights reserved.
+ */
+
+#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_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_first_bit(node_map, O2NM_MAX_NODES) >= 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_first_bit(node_map, O2NM_MAX_NODES) >= 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;
+ }
+
+ dlm_debug_init(dlm);
+
+ 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_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();
+
+ dlm_create_debugfs_subroot(dlm);
+
+ 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));
+
+ ret = 0;
+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;
+ }
+
+ dlm_create_debugfs_root();
+
+ 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);