tree-wide: fix assorted typos all over the place
[safe/jmp/linux-2.6] / fs / ocfs2 / dlm / dlmmaster.c
index 54e182a..03ccf9a 100644 (file)
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
@@ -73,22 +72,13 @@ static inline int dlm_mle_equal(struct dlm_ctxt *dlm,
                                const char *name,
                                unsigned int namelen)
 {
-       struct dlm_lock_resource *res;
-
        if (dlm != mle->dlm)
                return 0;
 
-       if (mle->type == DLM_MLE_BLOCK ||
-           mle->type == DLM_MLE_MIGRATION) {
-               if (namelen != mle->u.name.len ||
-                   memcmp(name, mle->u.name.name, namelen)!=0)
-                       return 0;
-       } else {
-               res = mle->u.res;
-               if (namelen != res->lockname.len ||
-                   memcmp(res->lockname.name, name, namelen) != 0)
-                       return 0;
-       }
+       if (namelen != mle->mnamelen ||
+           memcmp(name, mle->mname, namelen) != 0)
+               return 0;
+
        return 1;
 }
 
@@ -283,7 +273,7 @@ static void dlm_init_mle(struct dlm_master_list_entry *mle,
 
        mle->dlm = dlm;
        mle->type = type;
-       INIT_LIST_HEAD(&mle->list);
+       INIT_HLIST_NODE(&mle->master_hash_node);
        INIT_LIST_HEAD(&mle->hb_events);
        memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
        spin_lock_init(&mle->spinlock);
@@ -295,19 +285,27 @@ static void dlm_init_mle(struct dlm_master_list_entry *mle,
        mle->new_master = O2NM_MAX_NODES;
        mle->inuse = 0;
 
+       BUG_ON(mle->type != DLM_MLE_BLOCK &&
+              mle->type != DLM_MLE_MASTER &&
+              mle->type != DLM_MLE_MIGRATION);
+
        if (mle->type == DLM_MLE_MASTER) {
                BUG_ON(!res);
-               mle->u.res = res;
-       } else if (mle->type == DLM_MLE_BLOCK) {
-               BUG_ON(!name);
-               memcpy(mle->u.name.name, name, namelen);
-               mle->u.name.len = namelen;
-       } else /* DLM_MLE_MIGRATION */ {
+               mle->mleres = res;
+               memcpy(mle->mname, res->lockname.name, res->lockname.len);
+               mle->mnamelen = res->lockname.len;
+               mle->mnamehash = res->lockname.hash;
+       } else {
                BUG_ON(!name);
-               memcpy(mle->u.name.name, name, namelen);
-               mle->u.name.len = namelen;
+               mle->mleres = NULL;
+               memcpy(mle->mname, name, namelen);
+               mle->mnamelen = namelen;
+               mle->mnamehash = dlm_lockid_hash(name, namelen);
        }
 
+       atomic_inc(&dlm->mle_tot_count[mle->type]);
+       atomic_inc(&dlm->mle_cur_count[mle->type]);
+
        /* copy off the node_map and register hb callbacks on our copy */
        memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map));
        memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map));
@@ -318,6 +316,24 @@ static void dlm_init_mle(struct dlm_master_list_entry *mle,
        __dlm_mle_attach_hb_events(dlm, mle);
 }
 
+void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle)
+{
+       assert_spin_locked(&dlm->spinlock);
+       assert_spin_locked(&dlm->master_lock);
+
+       if (!hlist_unhashed(&mle->master_hash_node))
+               hlist_del_init(&mle->master_hash_node);
+}
+
+void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle)
+{
+       struct hlist_head *bucket;
+
+       assert_spin_locked(&dlm->master_lock);
+
+       bucket = dlm_master_hash(dlm, mle->mnamehash);
+       hlist_add_head(&mle->master_hash_node, bucket);
+}
 
 /* returns 1 if found, 0 if not */
 static int dlm_find_mle(struct dlm_ctxt *dlm,
@@ -325,10 +341,17 @@ static int dlm_find_mle(struct dlm_ctxt *dlm,
                        char *name, unsigned int namelen)
 {
        struct dlm_master_list_entry *tmpmle;
+       struct hlist_head *bucket;
+       struct hlist_node *list;
+       unsigned int hash;
 
        assert_spin_locked(&dlm->master_lock);
 
-       list_for_each_entry(tmpmle, &dlm->master_list, list) {
+       hash = dlm_lockid_hash(name, namelen);
+       bucket = dlm_master_hash(dlm, hash);
+       hlist_for_each(list, bucket) {
+               tmpmle = hlist_entry(list, struct dlm_master_list_entry,
+                                    master_hash_node);
                if (!dlm_mle_equal(dlm, tmpmle, name, namelen))
                        continue;
                dlm_get_mle(tmpmle);
@@ -408,24 +431,20 @@ static void dlm_mle_release(struct kref *kref)
        mle = container_of(kref, struct dlm_master_list_entry, mle_refs);
        dlm = mle->dlm;
 
-       if (mle->type != DLM_MLE_MASTER) {
-               mlog(0, "calling mle_release for %.*s, type %d\n",
-                    mle->u.name.len, mle->u.name.name, mle->type);
-       } else {
-               mlog(0, "calling mle_release for %.*s, type %d\n",
-                    mle->u.res->lockname.len,
-                    mle->u.res->lockname.name, mle->type);
-       }
        assert_spin_locked(&dlm->spinlock);
        assert_spin_locked(&dlm->master_lock);
 
+       mlog(0, "Releasing mle for %.*s, type %d\n", mle->mnamelen, mle->mname,
+            mle->type);
+
        /* remove from list if not already */
-       if (!list_empty(&mle->list))
-               list_del_init(&mle->list);
+       __dlm_unlink_mle(dlm, mle);
 
        /* detach the mle from the domain node up/down events */
        __dlm_mle_detach_hb_events(dlm, mle);
 
+       atomic_dec(&dlm->mle_cur_count[mle->type]);
+
        /* NOTE: kfree under spinlock here.
         * if this is bad, we can move this to a freelist. */
        kmem_cache_free(dlm_mle_cache, mle);
@@ -465,43 +484,6 @@ void dlm_destroy_master_caches(void)
                kmem_cache_destroy(dlm_lockres_cache);
 }
 
-static void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
-                                 struct dlm_lock_resource *res,
-                                 u8 owner)
-{
-       assert_spin_locked(&res->spinlock);
-
-       mlog_entry("%.*s, %u\n", res->lockname.len, res->lockname.name, owner);
-
-       if (owner == dlm->node_num)
-               atomic_inc(&dlm->local_resources);
-       else if (owner == DLM_LOCK_RES_OWNER_UNKNOWN)
-               atomic_inc(&dlm->unknown_resources);
-       else
-               atomic_inc(&dlm->remote_resources);
-
-       res->owner = owner;
-}
-
-void dlm_change_lockres_owner(struct dlm_ctxt *dlm,
-                             struct dlm_lock_resource *res, u8 owner)
-{
-       assert_spin_locked(&res->spinlock);
-
-       if (owner == res->owner)
-               return;
-
-       if (res->owner == dlm->node_num)
-               atomic_dec(&dlm->local_resources);
-       else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN)
-               atomic_dec(&dlm->unknown_resources);
-       else
-               atomic_dec(&dlm->remote_resources);
-
-       dlm_set_lockres_owner(dlm, res, owner);
-}
-
-
 static void dlm_lockres_release(struct kref *kref)
 {
        struct dlm_lock_resource *res;
@@ -527,6 +509,8 @@ static void dlm_lockres_release(struct kref *kref)
        }
        spin_unlock(&dlm->track_lock);
 
+       atomic_dec(&dlm->res_cur_count);
+
        dlm_put(dlm);
 
        if (!hlist_unhashed(&res->hash_node) ||
@@ -607,6 +591,9 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 
        kref_init(&res->refs);
 
+       atomic_inc(&dlm->res_tot_count);
+       atomic_inc(&dlm->res_cur_count);
+
        /* just for consistency */
        spin_lock(&res->spinlock);
        dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN);
@@ -843,7 +830,7 @@ lookup:
                alloc_mle = NULL;
                dlm_init_mle(mle, DLM_MLE_MASTER, dlm, res, NULL, 0);
                set_bit(dlm->node_num, mle->maybe_map);
-               list_add(&mle->list, &dlm->master_list);
+               __dlm_insert_mle(dlm, mle);
 
                /* still holding the dlm spinlock, check the recovery map
                 * to see if there are any nodes that still need to be 
@@ -1270,7 +1257,7 @@ static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm,
                                                     res->lockname.len,
                                                     res->lockname.name);
                                                mle->type = DLM_MLE_MASTER;
-                                               mle->u.res = res;
+                                               mle->mleres = res;
                                        }
                                }
                        }
@@ -1315,14 +1302,8 @@ static int dlm_do_master_request(struct dlm_lock_resource *res,
 
        BUG_ON(mle->type == DLM_MLE_MIGRATION);
 
-       if (mle->type != DLM_MLE_MASTER) {
-               request.namelen = mle->u.name.len;
-               memcpy(request.name, mle->u.name.name, request.namelen);
-       } else {
-               request.namelen = mle->u.res->lockname.len;
-               memcpy(request.name, mle->u.res->lockname.name,
-                       request.namelen);
-       }
+       request.namelen = (u8)mle->mnamelen;
+       memcpy(request.name, mle->mname, request.namelen);
 
 again:
        ret = o2net_send_message(DLM_MASTER_REQUEST_MSG, dlm->key, &request,
@@ -1575,7 +1556,7 @@ way_up_top:
                // "add the block.\n");
                dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, name, namelen);
                set_bit(request->node_idx, mle->maybe_map);
-               list_add(&mle->list, &dlm->master_list);
+               __dlm_insert_mle(dlm, mle);
                response = DLM_MASTER_RESP_NO;
        } else {
                // mlog(0, "mle was found\n");
@@ -1849,12 +1830,12 @@ int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
                if (!mle) {
                        if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN &&
                            res->owner != assert->node_idx) {
-                               mlog(ML_ERROR, "assert_master from "
-                                         "%u, but current owner is "
-                                         "%u! (%.*s)\n",
-                                      assert->node_idx, res->owner,
-                                      namelen, name);
-                               goto kill;
+                               mlog(ML_ERROR, "DIE! Mastery assert from %u, "
+                                    "but current owner is %u! (%.*s)\n",
+                                    assert->node_idx, res->owner, namelen,
+                                    name);
+                               __dlm_print_one_lock_resource(res);
+                               BUG();
                        }
                } else if (mle->type != DLM_MLE_MIGRATION) {
                        if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
@@ -1967,7 +1948,7 @@ ok:
                             assert->node_idx, rr, extra_ref, mle->inuse);
                        dlm_print_one_mle(mle);
                }
-               list_del_init(&mle->list);
+               __dlm_unlink_mle(dlm, mle);
                __dlm_mle_detach_hb_events(dlm, mle);
                __dlm_put_mle(mle);
                if (extra_ref) {
@@ -2605,7 +2586,7 @@ fail:
         * is complete everywhere.  if the target dies while this is
         * going on, some nodes could potentially see the target as the
         * master, so it is important that my recovery finds the migration
-        * mle and sets the master to UNKNONWN. */
+        * mle and sets the master to UNKNOWN. */
 
 
        /* wait for new node to assert master */
@@ -3159,10 +3140,8 @@ static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
                        tmp->master = master;
                        atomic_set(&tmp->woken, 1);
                        wake_up(&tmp->wq);
-                       /* remove it from the list so that only one
-                        * mle will be found */
-                       list_del_init(&tmp->list);
-                       /* this was obviously WRONG.  mle is uninited here.  should be tmp. */
+                       /* remove it so that only one mle will be found */
+                       __dlm_unlink_mle(dlm, tmp);
                        __dlm_mle_detach_hb_events(dlm, tmp);
                        ret = DLM_MIGRATE_RESPONSE_MASTERY_REF;
                        mlog(0, "%s:%.*s: master=%u, newmaster=%u, "
@@ -3181,137 +3160,164 @@ static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
        mle->master = master;
        /* do this for consistency with other mle types */
        set_bit(new_master, mle->maybe_map);
-       list_add(&mle->list, &dlm->master_list);
+       __dlm_insert_mle(dlm, mle);
 
        return ret;
 }
 
-
-void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node)
+/*
+ * Sets the owner of the lockres, associated to the mle, to UNKNOWN
+ */
+static struct dlm_lock_resource *dlm_reset_mleres_owner(struct dlm_ctxt *dlm,
+                                       struct dlm_master_list_entry *mle)
 {
-       struct dlm_master_list_entry *mle, *next;
        struct dlm_lock_resource *res;
-       unsigned int hash;
 
-       mlog_entry("dlm=%s, dead node=%u\n", dlm->name, dead_node);
-top:
-       assert_spin_locked(&dlm->spinlock);
+       /* Find the lockres associated to the mle and set its owner to UNK */
+       res = __dlm_lookup_lockres(dlm, mle->mname, mle->mnamelen,
+                                  mle->mnamehash);
+       if (res) {
+               spin_unlock(&dlm->master_lock);
 
-       /* clean the master list */
-       spin_lock(&dlm->master_lock);
-       list_for_each_entry_safe(mle, next, &dlm->master_list, list) {
-               BUG_ON(mle->type != DLM_MLE_BLOCK &&
-                      mle->type != DLM_MLE_MASTER &&
-                      mle->type != DLM_MLE_MIGRATION);
-
-               /* MASTER mles are initiated locally.  the waiting
-                * process will notice the node map change
-                * shortly.  let that happen as normal. */
-               if (mle->type == DLM_MLE_MASTER)
-                       continue;
+               /* move lockres onto recovery list */
+               spin_lock(&res->spinlock);
+               dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN);
+               dlm_move_lockres_to_recovery_list(dlm, res);
+               spin_unlock(&res->spinlock);
+               dlm_lockres_put(res);
 
+               /* about to get rid of mle, detach from heartbeat */
+               __dlm_mle_detach_hb_events(dlm, mle);
 
-               /* BLOCK mles are initiated by other nodes.
-                * need to clean up if the dead node would have
-                * been the master. */
-               if (mle->type == DLM_MLE_BLOCK) {
-                       int bit;
+               /* dump the mle */
+               spin_lock(&dlm->master_lock);
+               __dlm_put_mle(mle);
+               spin_unlock(&dlm->master_lock);
+       }
 
-                       spin_lock(&mle->spinlock);
-                       bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
-                       if (bit != dead_node) {
-                               mlog(0, "mle found, but dead node %u would "
-                                    "not have been master\n", dead_node);
-                               spin_unlock(&mle->spinlock);
-                       } else {
-                               /* must drop the refcount by one since the
-                                * assert_master will never arrive.  this
-                                * may result in the mle being unlinked and
-                                * freed, but there may still be a process
-                                * waiting in the dlmlock path which is fine. */
-                               mlog(0, "node %u was expected master\n",
-                                    dead_node);
-                               atomic_set(&mle->woken, 1);
-                               spin_unlock(&mle->spinlock);
-                               wake_up(&mle->wq);
-                               /* do not need events any longer, so detach 
-                                * from heartbeat */
-                               __dlm_mle_detach_hb_events(dlm, mle);
-                               __dlm_put_mle(mle);
-                       }
-                       continue;
-               }
+       return res;
+}
 
-               /* everything else is a MIGRATION mle */
-
-               /* the rule for MIGRATION mles is that the master
-                * becomes UNKNOWN if *either* the original or
-                * the new master dies.  all UNKNOWN lockreses
-                * are sent to whichever node becomes the recovery
-                * master.  the new master is responsible for
-                * determining if there is still a master for
-                * this lockres, or if he needs to take over
-                * mastery.  either way, this node should expect
-                * another message to resolve this. */
-               if (mle->master != dead_node &&
-                   mle->new_master != dead_node)
-                       continue;
+static void dlm_clean_migration_mle(struct dlm_ctxt *dlm,
+                                   struct dlm_master_list_entry *mle)
+{
+       __dlm_mle_detach_hb_events(dlm, mle);
 
-               /* if we have reached this point, this mle needs to
-                * be removed from the list and freed. */
+       spin_lock(&mle->spinlock);
+       __dlm_unlink_mle(dlm, mle);
+       atomic_set(&mle->woken, 1);
+       spin_unlock(&mle->spinlock);
 
-               /* remove from the list early.  NOTE: unlinking
-                * list_head while in list_for_each_safe */
-               __dlm_mle_detach_hb_events(dlm, mle);
-               spin_lock(&mle->spinlock);
-               list_del_init(&mle->list);
+       wake_up(&mle->wq);
+}
+
+static void dlm_clean_block_mle(struct dlm_ctxt *dlm,
+                               struct dlm_master_list_entry *mle, u8 dead_node)
+{
+       int bit;
+
+       BUG_ON(mle->type != DLM_MLE_BLOCK);
+
+       spin_lock(&mle->spinlock);
+       bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
+       if (bit != dead_node) {
+               mlog(0, "mle found, but dead node %u would not have been "
+                    "master\n", dead_node);
+               spin_unlock(&mle->spinlock);
+       } else {
+               /* Must drop the refcount by one since the assert_master will
+                * never arrive. This may result in the mle being unlinked and
+                * freed, but there may still be a process waiting in the
+                * dlmlock path which is fine. */
+               mlog(0, "node %u was expected master\n", dead_node);
                atomic_set(&mle->woken, 1);
                spin_unlock(&mle->spinlock);
                wake_up(&mle->wq);
 
-               mlog(0, "%s: node %u died during migration from "
-                    "%u to %u!\n", dlm->name, dead_node,
-                    mle->master, mle->new_master);
-               /* if there is a lockres associated with this
-                * mle, find it and set its owner to UNKNOWN */
-               hash = dlm_lockid_hash(mle->u.name.name, mle->u.name.len);
-               res = __dlm_lookup_lockres(dlm, mle->u.name.name,
-                                          mle->u.name.len, hash);
-               if (res) {
-                       /* unfortunately if we hit this rare case, our
-                        * lock ordering is messed.  we need to drop
-                        * the master lock so that we can take the
-                        * lockres lock, meaning that we will have to
-                        * restart from the head of list. */
-                       spin_unlock(&dlm->master_lock);
+               /* Do not need events any longer, so detach from heartbeat */
+               __dlm_mle_detach_hb_events(dlm, mle);
+               __dlm_put_mle(mle);
+       }
+}
 
-                       /* move lockres onto recovery list */
-                       spin_lock(&res->spinlock);
-                       dlm_set_lockres_owner(dlm, res,
-                                       DLM_LOCK_RES_OWNER_UNKNOWN);
-                       dlm_move_lockres_to_recovery_list(dlm, res);
-                       spin_unlock(&res->spinlock);
-                       dlm_lockres_put(res);
+void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node)
+{
+       struct dlm_master_list_entry *mle;
+       struct dlm_lock_resource *res;
+       struct hlist_head *bucket;
+       struct hlist_node *list;
+       unsigned int i;
 
-                       /* about to get rid of mle, detach from heartbeat */
-                       __dlm_mle_detach_hb_events(dlm, mle);
+       mlog_entry("dlm=%s, dead node=%u\n", dlm->name, dead_node);
+top:
+       assert_spin_locked(&dlm->spinlock);
 
-                       /* dump the mle */
-                       spin_lock(&dlm->master_lock);
-                       __dlm_put_mle(mle);
-                       spin_unlock(&dlm->master_lock);
+       /* clean the master list */
+       spin_lock(&dlm->master_lock);
+       for (i = 0; i < DLM_HASH_BUCKETS; i++) {
+               bucket = dlm_master_hash(dlm, i);
+               hlist_for_each(list, bucket) {
+                       mle = hlist_entry(list, struct dlm_master_list_entry,
+                                         master_hash_node);
+
+                       BUG_ON(mle->type != DLM_MLE_BLOCK &&
+                              mle->type != DLM_MLE_MASTER &&
+                              mle->type != DLM_MLE_MIGRATION);
+
+                       /* MASTER mles are initiated locally. The waiting
+                        * process will notice the node map change shortly.
+                        * Let that happen as normal. */
+                       if (mle->type == DLM_MLE_MASTER)
+                               continue;
+
+                       /* BLOCK mles are initiated by other nodes. Need to
+                        * clean up if the dead node would have been the
+                        * master. */
+                       if (mle->type == DLM_MLE_BLOCK) {
+                               dlm_clean_block_mle(dlm, mle, dead_node);
+                               continue;
+                       }
 
-                       /* restart */
-                       goto top;
-               }
+                       /* Everything else is a MIGRATION mle */
+
+                       /* The rule for MIGRATION mles is that the master
+                        * becomes UNKNOWN if *either* the original or the new
+                        * master dies. All UNKNOWN lockres' are sent to
+                        * whichever node becomes the recovery master. The new
+                        * master is responsible for determining if there is
+                        * still a master for this lockres, or if he needs to
+                        * take over mastery. Either way, this node should
+                        * expect another message to resolve this. */
+
+                       if (mle->master != dead_node &&
+                           mle->new_master != dead_node)
+                               continue;
+
+                       /* If we have reached this point, this mle needs to be
+                        * removed from the list and freed. */
+                       dlm_clean_migration_mle(dlm, mle);
+
+                       mlog(0, "%s: node %u died during migration from "
+                            "%u to %u!\n", dlm->name, dead_node, mle->master,
+                            mle->new_master);
+
+                       /* If we find a lockres associated with the mle, we've
+                        * hit this rare case that messes up our lock ordering.
+                        * If so, we need to drop the master lock so that we can
+                        * take the lockres lock, meaning that we will have to
+                        * restart from the head of list. */
+                       res = dlm_reset_mleres_owner(dlm, mle);
+                       if (res)
+                               /* restart */
+                               goto top;
 
-               /* this may be the last reference */
-               __dlm_put_mle(mle);
+                       /* This may be the last reference */
+                       __dlm_put_mle(mle);
+               }
        }
        spin_unlock(&dlm->master_lock);
 }
 
-
 int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
                         u8 old_master)
 {