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* Chain granted locks off the export.
[fs/lustre-release.git] / lustre / ldlm / ldlm_lock.c
index 4c922d9..d1edbdb 100644 (file)
 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
  * vim:expandtab:shiftwidth=8:tabstop=8:
  *
- * Copyright (C) 2002 Cluster File Systems, Inc.
+ *  Copyright (c) 2002 Cluster File Systems, Inc.
+ *   Author: Peter Braam <braam@clusterfs.com>
+ *   Author: Phil Schwan <phil@clusterfs.com>
  *
- * This code is issued under the GNU General Public License.
- * See the file COPYING in this distribution
+ *   This file is part of Lustre, http://www.lustre.org.
  *
- * by Cluster File Systems, Inc.
- * authors, Peter Braam <braam@clusterfs.com> &
- * Phil Schwan <phil@clusterfs.com>
+ *   Lustre is free software; you can redistribute it and/or
+ *   modify it under the terms of version 2 of the GNU General Public
+ *   License as published by the Free Software Foundation.
+ *
+ *   Lustre 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 Lustre; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
 #define DEBUG_SUBSYSTEM S_LDLM
 
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/random.h>
 #include <linux/lustre_dlm.h>
 #include <linux/lustre_mds.h>
+#include <linux/obd_class.h>
+
+/* lock types */
+char *ldlm_lockname[] = {
+        [0] "--",
+        [LCK_EX] "EX",
+        [LCK_PW] "PW",
+        [LCK_PR] "PR",
+        [LCK_CW] "CW",
+        [LCK_CR] "CR",
+        [LCK_NL] "NL"
+};
+char *ldlm_typename[] = {
+        [LDLM_PLAIN] "PLN",
+        [LDLM_EXTENT] "EXT",
+        [LDLM_MDSINTENT] "INT"
+};
+
+char *ldlm_it2str(int it)
+{
+        switch (it) {
+        case IT_OPEN:
+                return "open";
+        case IT_CREAT:
+                return "creat";
+        case (IT_OPEN | IT_CREAT):
+                return "open|creat";
+        case IT_MKDIR:
+                return "mkdir";
+        case IT_LINK:
+                return "link";
+        case IT_SYMLINK:
+                return "symlink";
+        case IT_UNLINK:
+                return "unlink";
+        case IT_RMDIR:
+                return "rmdir";
+        case IT_RENAME:
+                return "rename";
+        case IT_RENAME2:
+                return "rename2";
+        case IT_READDIR:
+                return "readdir";
+        case IT_GETATTR:
+                return "getattr";
+        case IT_SETATTR:
+                return "setattr";
+        case IT_READLINK:
+                return "readlink";
+        case IT_MKNOD:
+                return "mknod";
+        case IT_LOOKUP:
+                return "lookup";
+        default:
+                CERROR("Unknown intent %d\n", it);
+                return "UNKNOWN";
+        }
+}
 
 extern kmem_cache_t *ldlm_lock_slab;
-int (*mds_reint_p)(int offset, struct ptlrpc_request *req) = NULL;
-int (*mds_getattr_name_p)(int offset, struct ptlrpc_request *req) = NULL;
 
 static int ldlm_plain_compat(struct ldlm_lock *a, struct ldlm_lock *b);
-static int ldlm_intent_policy(struct ldlm_lock *lock, void *req_cookie,
-                              ldlm_mode_t mode, void *data);
 
-ldlm_res_compat ldlm_res_compat_table [] = {
+ldlm_res_compat ldlm_res_compat_table[] = {
         [LDLM_PLAIN] ldlm_plain_compat,
         [LDLM_EXTENT] ldlm_extent_compat,
         [LDLM_MDSINTENT] ldlm_plain_compat
 };
 
-ldlm_res_policy ldlm_res_policy_table [] = {
+ldlm_res_policy ldlm_res_policy_table[] = {
         [LDLM_PLAIN] NULL,
         [LDLM_EXTENT] ldlm_extent_policy,
-        [LDLM_MDSINTENT] ldlm_intent_policy
+        [LDLM_MDSINTENT] NULL
 };
 
-static int ldlm_intent_policy(struct ldlm_lock *lock, void *req_cookie,
-                              ldlm_mode_t mode, void *data)
+void ldlm_register_intent(int (*arg) (struct ldlm_lock * lock, void *req_cookie,
+                                      ldlm_mode_t mode, void *data))
 {
-        struct ptlrpc_request *req = req_cookie;
-        int rc = 0;
-        ENTRY;
+        ldlm_res_policy_table[LDLM_MDSINTENT] = arg;
+}
 
-        if (!req_cookie)
-                RETURN(0);
+void ldlm_unregister_intent(void)
+{
+        ldlm_res_policy_table[LDLM_MDSINTENT] = NULL;
+}
 
-        if (req->rq_reqmsg->bufcount > 1) {
-                /* an intent needs to be considered */
-                struct ldlm_intent *it = lustre_msg_buf(req->rq_reqmsg, 1);
-                struct mds_body *mds_rep;
-                struct ldlm_reply *rep;
-                struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
-                __u32 type = lock->l_resource->lr_type;
-                __u64 new_resid[3] = {0, 0, 0}, old_res;
-                int bufcount = -1, rc, size[3] = {sizeof(struct ldlm_reply),
-                                                  sizeof(struct mds_body),
-                                                  sizeof(struct obdo)};
-
-                it->opc = NTOH__u64(it->opc);
-
-                LDLM_DEBUG(lock, "intent policy, opc: %Ld", it->opc);
-
-                /* prepare reply */
-                switch(it->opc) {
-                case IT_GETATTR:
-                        /* Note that in the negative case you may be returning
-                         * a file and its obdo */
-                case IT_CREAT:
-                case IT_CREAT|IT_OPEN:
-                case IT_MKDIR:
-                case IT_SYMLINK:
-                case IT_MKNOD:
-                case IT_LINK:
-                case IT_OPEN:
-                case IT_RENAME:
-                        bufcount = 3;
-                        break;
-                case IT_UNLINK:
-                        bufcount = 2;
-                        size[1] = sizeof(struct obdo);
-                        break;
-                case IT_RMDIR:
-                        bufcount = 1;
-                        break;
-                default:
-                        LBUG();
-                }
+/*
+ * REFCOUNTED LOCK OBJECTS
+ */
 
-                rc = lustre_pack_msg(bufcount, size, NULL, &req->rq_replen,
-                                     &req->rq_repmsg);
-                if (rc) {
-                        rc = req->rq_status = -ENOMEM;
-                        RETURN(rc);
-                }
 
-                rep = lustre_msg_buf(req->rq_repmsg, 0);
-                rep->lock_policy_res1 = 1;
-
-                /* execute policy */
-                switch (it->opc) {
-                case IT_CREAT:
-                case IT_CREAT|IT_OPEN:
-                case IT_MKDIR:
-                case IT_SETATTR:
-                case IT_SYMLINK:
-                case IT_MKNOD:
-                case IT_LINK:
-                case IT_UNLINK:
-                case IT_RMDIR:
-                case IT_RENAME2:
-                        if (mds_reint_p == NULL)
-                                mds_reint_p =
-                                        inter_module_get_request
-                                        ("mds_reint", "mds");
-                        if (IS_ERR(mds_reint_p)) {
-                                CERROR("MDSINTENT locks require the MDS "
-                                       "module.\n");
-                                LBUG();
-                                RETURN(-EINVAL);
-                        }
-                        rc = mds_reint_p(2, req);
-                        if (rc)
-                                LBUG();
-                        break;
-                case IT_GETATTR:
-                case IT_READDIR:
-                case IT_RENAME:
-                case IT_OPEN:
-                        if (mds_getattr_name_p == NULL)
-                                mds_getattr_name_p =
-                                        inter_module_get_request
-                                        ("mds_getattr_name", "mds");
-                        if (IS_ERR(mds_getattr_name_p)) {
-                                CERROR("MDSINTENT locks require the MDS "
-                                       "module.\n");
-                                LBUG();
-                                RETURN(-EINVAL);
-                        }
-                        rc = mds_getattr_name_p(2, req);
-                        if (rc) {
-                                req->rq_status = rc;
-                                RETURN(rc);
-                        }
-                        break;
-                case IT_READDIR|IT_OPEN:
-                        LBUG();
-                        break;
-                default:
-                        CERROR("Unhandled intent\n");
-                        LBUG();
-                }
-
-                if (it->opc == IT_UNLINK || it->opc == IT_RMDIR)
-                        RETURN(ELDLM_LOCK_ABORTED);
+/*
+ * Lock refcounts, during creation:
+ *   - one special one for allocation, dec'd only once in destroy
+ *   - one for being a lock that's in-use
+ *   - one for the addref associated with a new lock
+ */
+struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock)
+{
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+        lock->l_refc++;
+        ldlm_resource_getref(lock->l_resource);
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+        return lock;
+}
 
-                mds_rep = lustre_msg_buf(req->rq_repmsg, 1);
-                rep->lock_policy_res2 = req->rq_status;
-                new_resid[0] = mds_rep->ino;
-                old_res = lock->l_resource->lr_name[0];
+void ldlm_lock_put(struct ldlm_lock *lock)
+{
+        struct lustre_lock *nslock = &lock->l_resource->lr_namespace->ns_lock;
+        ENTRY;
 
-                CDEBUG(D_INFO, "remote intent: locking %d instead of"
-                       "%ld\n", mds_rep->ino, (long)old_res);
-                spin_lock(&lock->l_resource->lr_lock);
-                if (!ldlm_resource_put(lock->l_resource))
-                        /* unlock it unless the resource was freed */
-                        spin_unlock(&lock->l_resource->lr_lock);
+        l_lock(nslock);
+        lock->l_refc--;
+        //LDLM_DEBUG(lock, "after refc--");
+        if (lock->l_refc < 0)
+                LBUG();
 
-                lock->l_resource =
-                        ldlm_resource_get(ns, NULL, new_resid, type, 1);
-                if (lock->l_resource == NULL) {
-                        LBUG();
-                        RETURN(-ENOMEM);
-                }
-                LDLM_DEBUG(lock, "intent policy, old res %ld",
-                           (long)old_res);
-                RETURN(ELDLM_LOCK_CHANGED);
-        } else {
-                int size = sizeof(struct ldlm_reply);
-                rc = lustre_pack_msg(1, &size, NULL, &req->rq_replen,
-                                     &req->rq_repmsg);
-                if (rc) {
-                        CERROR("out of memory\n");
-                        LBUG();
-                        RETURN(-ENOMEM);
-                }
+        ldlm_resource_put(lock->l_resource);
+        if (lock->l_parent)
+                LDLM_LOCK_PUT(lock->l_parent);
+
+        if (lock->l_refc == 0 && (lock->l_flags & LDLM_FL_DESTROYED)) {
+                lock->l_resource = NULL;
+                LDLM_DEBUG(lock, "final lock_put on destroyed lock, freeing");
+                if (lock->l_export && lock->l_export->exp_connection)
+                        ptlrpc_put_connection(lock->l_export->exp_connection);
+                CDEBUG(D_MALLOC, "kfreed 'lock': %d at %p (tot 1).\n",
+                       sizeof(*lock), lock);
+                kmem_cache_free(ldlm_lock_slab, lock);
         }
-        RETURN(rc);
+        l_unlock(nslock);
+        EXIT;
 }
 
-static int ldlm_plain_compat(struct ldlm_lock *a, struct ldlm_lock *b)
+void ldlm_lock_destroy(struct ldlm_lock *lock)
 {
-        return lockmode_compat(a->l_req_mode, b->l_req_mode);
+        ENTRY;
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+
+        if (!list_empty(&lock->l_children)) {
+                LDLM_DEBUG(lock, "still has children (%p)!",
+                           lock->l_children.next);
+                ldlm_lock_dump(lock);
+                LBUG();
+        }
+        if (lock->l_readers || lock->l_writers) {
+                LDLM_DEBUG(lock, "lock still has references");
+                ldlm_lock_dump(lock);
+                LBUG();
+        }
+
+        if (!list_empty(&lock->l_res_link)) {
+                ldlm_lock_dump(lock);
+                LBUG();
+        }
+
+        if (lock->l_flags & LDLM_FL_DESTROYED) {
+                l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+                EXIT;
+                return;
+        }
+
+        list_del(&lock->l_export_chain);
+        lock->l_export = NULL;
+        lock->l_flags = LDLM_FL_DESTROYED;
+
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+        LDLM_LOCK_PUT(lock);
+        EXIT;
 }
 
-/* Args: referenced, unlocked parent (or NULL)
- *       referenced, unlocked resource
- * Locks: parent->l_lock */
+/*
+   usage: pass in a resource on which you have done get
+          pass in a parent lock on which you have done a get
+          do not put the resource or the parent
+   returns: lock with refcount 1
+*/
 static struct ldlm_lock *ldlm_lock_new(struct ldlm_lock *parent,
                                        struct ldlm_resource *resource)
 {
         struct ldlm_lock *lock;
+        ENTRY;
 
         if (resource == NULL)
                 LBUG();
 
         lock = kmem_cache_alloc(ldlm_lock_slab, SLAB_KERNEL);
         if (lock == NULL)
-                return NULL;
+                RETURN(NULL);
+        CDEBUG(D_MALLOC, "kmalloced 'lock': %d at "
+               "%p (tot %d).\n", sizeof(*lock), lock, 1);
 
         memset(lock, 0, sizeof(*lock));
+        get_random_bytes(&lock->l_random, sizeof(__u64));
+
         lock->l_resource = resource;
+        /* this refcount matches the one of the resource passed
+           in which is not being put away */
+        lock->l_refc = 1;
         INIT_LIST_HEAD(&lock->l_children);
         INIT_LIST_HEAD(&lock->l_res_link);
+        INIT_LIST_HEAD(&lock->l_inode_link);
+        INIT_LIST_HEAD(&lock->l_export_chain);
+        INIT_LIST_HEAD(&lock->l_pending_chain);
         init_waitqueue_head(&lock->l_waitq);
-        lock->l_lock = SPIN_LOCK_UNLOCKED;
 
         if (parent != NULL) {
-                spin_lock(&parent->l_lock);
+                l_lock(&parent->l_resource->lr_namespace->ns_lock);
                 lock->l_parent = parent;
                 list_add(&lock->l_childof, &parent->l_children);
-                spin_unlock(&parent->l_lock);
+                l_unlock(&parent->l_resource->lr_namespace->ns_lock);
         }
-
-        return lock;
+        /* this is the extra refcount, to prevent the lock
+           evaporating */
+        LDLM_LOCK_GET(lock);
+        RETURN(lock);
 }
 
-/* Args: unreferenced, locked lock
- *
- * Caller must do its own ldlm_resource_put() on lock->l_resource */
-void ldlm_lock_free(struct ldlm_lock *lock)
+int ldlm_lock_change_resource(struct ldlm_lock *lock, __u64 new_resid[3])
 {
-        if (!list_empty(&lock->l_children)) {
-                CERROR("lock %p still has children (%p)!\n", lock,
-                       lock->l_children.next);
-                ldlm_lock_dump(lock);
+        struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
+        struct ldlm_resource *oldres = lock->l_resource;
+        int type, i;
+        ENTRY;
+
+        l_lock(&ns->ns_lock);
+        if (memcmp(new_resid, lock->l_resource->lr_name,
+                   sizeof(lock->l_resource->lr_name)) == 0) {
+                /* Nothing to do */
+                l_unlock(&ns->ns_lock);
+                RETURN(0);
+        }
+
+        type = lock->l_resource->lr_type;
+        if (new_resid[0] == 0)
                 LBUG();
+        lock->l_resource = ldlm_resource_get(ns, NULL, new_resid, type, 1);
+        if (lock->l_resource == NULL) {
+                LBUG();
+                RETURN(-ENOMEM);
         }
 
-        if (lock->l_readers || lock->l_writers)
-                CDEBUG(D_INFO, "lock still has references (%d readers, %d "
-                       "writers)\n", lock->l_readers, lock->l_writers);
+        /* move references over */
+        for (i = 0; i < lock->l_refc; i++) {
+                int rc;
+                ldlm_resource_getref(lock->l_resource);
+                rc = ldlm_resource_put(oldres);
+                if (rc == 1 && i != lock->l_refc - 1)
+                        LBUG();
+        }
+        /* compensate for the initial get above.. */
+        ldlm_resource_put(lock->l_resource);
+
+        l_unlock(&ns->ns_lock);
+        RETURN(0);
+}
+
+/*
+ *  HANDLES
+ */
+
+void ldlm_lock2handle(struct ldlm_lock *lock, struct lustre_handle *lockh)
+{
+        lockh->addr = (__u64) (unsigned long)lock;
+        lockh->cookie = lock->l_random;
+}
+
+struct ldlm_lock *ldlm_handle2lock(struct lustre_handle *handle)
+{
+        struct ldlm_lock *lock = NULL, *retval = NULL;
+        ENTRY;
+
+        if (!handle || !handle->addr)
+                RETURN(NULL);
+
+        lock = (struct ldlm_lock *)(unsigned long)(handle->addr);
+        if (!kmem_cache_validate(ldlm_lock_slab, (void *)lock))
+                RETURN(NULL);
+
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+        if (lock->l_random != handle->cookie)
+                GOTO(out, NULL);
+
+        if (lock->l_flags & LDLM_FL_DESTROYED)
+                GOTO(out, NULL);
+
+        retval = LDLM_LOCK_GET(lock);
+        EXIT;
+      out:
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+        return retval;
+}
 
-        if (lock->l_connection)
-                ptlrpc_put_connection(lock->l_connection);
-        kmem_cache_free(ldlm_lock_slab, lock);
+static int ldlm_plain_compat(struct ldlm_lock *a, struct ldlm_lock *b)
+{
+        return lockmode_compat(a->l_req_mode, b->l_req_mode);
 }
 
 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
@@ -258,76 +335,102 @@ void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
         memcpy(desc->l_version, lock->l_version, sizeof(desc->l_version));
 }
 
-/* Args: unlocked lock */
-void ldlm_lock_addref(struct ldlm_lock *lock, __u32 mode)
-{
-        spin_lock(&lock->l_lock);
-        if (mode == LCK_NL || mode == LCK_CR || mode == LCK_PR)
-                lock->l_readers++;
-        else
-                lock->l_writers++;
-        spin_unlock(&lock->l_lock);
-}
-
-int ldlm_send_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock *new)
+static void ldlm_add_ast_work_item(struct ldlm_lock *lock,
+                                   struct ldlm_lock *new)
 {
-        struct ptlrpc_request *req = NULL;
+        struct ldlm_ast_work *w;
         ENTRY;
 
-        spin_lock(&lock->l_lock);
-        if (lock->l_flags & LDLM_FL_AST_SENT)
-                RETURN(0);
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+        if (new && (lock->l_flags & LDLM_FL_AST_SENT))
+                GOTO(out, 0);
 
-        lock->l_flags |= LDLM_FL_AST_SENT;
+        OBD_ALLOC(w, sizeof(*w));
+        if (!w) {
+                LBUG();
+                GOTO(out, 0);
+        }
 
-        lock->l_blocking_ast(lock, new, lock->l_data, lock->l_data_len, &req);
-        spin_unlock(&lock->l_lock);
-        if (req != NULL) {
-                struct list_head *list = lock->l_resource->lr_tmp;
-                list_add(&req->rq_multi, list);
+        if (new) {
+                lock->l_flags |= LDLM_FL_AST_SENT;
+                w->w_blocking = 1;
+                ldlm_lock2desc(new, &w->w_desc);
         }
-        RETURN(1);
+
+        w->w_lock = LDLM_LOCK_GET(lock);
+        list_add(&w->w_list, lock->l_resource->lr_tmp);
+      out:
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+        return;
+}
+
+void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
+{
+        struct ldlm_lock *lock;
+
+        lock = ldlm_handle2lock(lockh);
+        ldlm_lock_addref_internal(lock, mode);
+        LDLM_LOCK_PUT(lock);
+}
+
+/* only called for local locks */
+void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
+{
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+        if (mode == LCK_NL || mode == LCK_CR || mode == LCK_PR)
+                lock->l_readers++;
+        else
+                lock->l_writers++;
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+        LDLM_LOCK_GET(lock);
+        LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 }
 
 /* Args: unlocked lock */
-void ldlm_lock_decref(struct ldlm_lock *lock, __u32 mode)
+void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 {
+        struct ldlm_lock *lock = ldlm_handle2lock(lockh);
         ENTRY;
 
         if (lock == NULL)
                 LBUG();
 
-        spin_lock(&lock->l_lock);
+        LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
         if (mode == LCK_NL || mode == LCK_CR || mode == LCK_PR)
                 lock->l_readers--;
         else
                 lock->l_writers--;
+
+        /* If we received a blocked AST and this was the last reference,
+         * run the callback. */
         if (!lock->l_readers && !lock->l_writers &&
-            lock->l_flags & LDLM_FL_DYING) {
-                /* Read this lock its rights. */
+            (lock->l_flags & LDLM_FL_CBPENDING)) {
                 if (!lock->l_resource->lr_namespace->ns_client) {
-                        CERROR("LDLM_FL_DYING set on non-local lock!\n");
+                        CERROR("LDLM_FL_CBPENDING set on non-local lock!\n");
                         LBUG();
                 }
 
-                CDEBUG(D_INFO, "final decref done on dying lock, "
-                       "calling callback.\n");
-                spin_unlock(&lock->l_lock);
-                /* This function pointer is unfortunately overloaded.  This
-                 * call will not result in an RPC. */
+                LDLM_DEBUG(lock, "final decref done on cbpending lock");
+                l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+
+                /* FIXME: need a real 'desc' here */
                 lock->l_blocking_ast(lock, NULL, lock->l_data,
-                                     lock->l_data_len, NULL);
+                                     lock->l_data_len);
         } else
-                spin_unlock(&lock->l_lock);
+                l_unlock(&lock->l_resource->lr_namespace->ns_lock);
+
+        LDLM_LOCK_PUT(lock);    /* matches the ldlm_lock_get in addref */
+        LDLM_LOCK_PUT(lock);    /* matches the handle2lock above */
+
         EXIT;
 }
 
-/* Args: unlocked lock */
-static int _ldlm_lock_compat(struct ldlm_lock *lock, int send_cbs,
-                             struct list_head *queue)
+static int ldlm_lock_compat_list(struct ldlm_lock *lock, int send_cbs,
+                                 struct list_head *queue)
 {
         struct list_head *tmp, *pos;
-        int rc = 0;
+        int rc = 1;
 
         list_for_each_safe(tmp, pos, queue) {
                 struct ldlm_lock *child;
@@ -338,7 +441,7 @@ static int _ldlm_lock_compat(struct ldlm_lock *lock, int send_cbs,
                         continue;
 
                 compat = ldlm_res_compat_table[child->l_resource->lr_type];
-                if (compat(child, lock)) {
+                if (compat && compat(child, lock)) {
                         CDEBUG(D_OTHER, "compat function succeded, next.\n");
                         continue;
                 }
@@ -347,44 +450,44 @@ static int _ldlm_lock_compat(struct ldlm_lock *lock, int send_cbs,
                         continue;
                 }
 
-                rc = 1;
+                rc = 0;
 
-                CDEBUG(D_OTHER, "compat function failed and lock modes "
-                       "incompat\n");
                 if (send_cbs && child->l_blocking_ast != NULL) {
-                        CDEBUG(D_OTHER, "incompatible; sending blocking "
-                               "AST.\n");
-                        /* It's very difficult to actually send the AST from
-                         * here, because we'd have to drop the lock before going
-                         * to sleep to wait for the reply.  Instead we build the
-                         * packet and send it later. */
-                        ldlm_send_blocking_ast(child, lock);
+                        CDEBUG(D_OTHER, "lock %p incompatible; sending "
+                               "blocking AST.\n", child);
+                        ldlm_add_ast_work_item(child, lock);
                 }
         }
 
         return rc;
 }
 
-/* Args: unlocked lock */
 static int ldlm_lock_compat(struct ldlm_lock *lock, int send_cbs)
 {
         int rc;
         ENTRY;
 
-        rc = _ldlm_lock_compat(lock, send_cbs, &lock->l_resource->lr_granted);
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
+        rc = ldlm_lock_compat_list(lock, send_cbs,
+                                   &lock->l_resource->lr_granted);
         /* FIXME: should we be sending ASTs to converting? */
-        rc |= _ldlm_lock_compat(lock, send_cbs,
-                                &lock->l_resource->lr_converting);
+        if (rc)
+                rc = ldlm_lock_compat_list
+                        (lock, send_cbs, &lock->l_resource->lr_converting);
 
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
         RETURN(rc);
 }
 
-/* Args: locked lock, locked resource */
-void ldlm_grant_lock(struct ldlm_resource *res, struct ldlm_lock *lock)
+/* NOTE: called by
+   - ldlm_handle_enqueuque - resource
+*/
+void ldlm_grant_lock(struct ldlm_lock *lock)
 {
-        struct ptlrpc_request *req = NULL;
+        struct ldlm_resource *res = lock->l_resource;
         ENTRY;
 
+        l_lock(&lock->l_resource->lr_namespace->ns_lock);
         ldlm_resource_add_lock(res, &res->lr_granted, lock);
         lock->l_granted_mode = lock->l_req_mode;
 
@@ -392,30 +495,23 @@ void ldlm_grant_lock(struct ldlm_resource *res, struct ldlm_lock *lock)
                 res->lr_most_restr = lock->l_granted_mode;
 
         if (lock->l_completion_ast) {
-                lock->l_completion_ast(lock, NULL, lock->l_data,
-                                       lock->l_data_len, &req);
-                if (req != NULL) {
-                        struct list_head *list = res->lr_tmp;
-                        if (list == NULL) {
-                                LBUG();
-                                return;
-                        }
-                        list_add(&req->rq_multi, list);
-                }
+                ldlm_add_ast_work_item(lock, NULL);
         }
+        l_unlock(&lock->l_resource->lr_namespace->ns_lock);
         EXIT;
 }
 
-static int search_queue(struct list_head *queue, ldlm_mode_t mode,
-                        struct ldlm_extent *extent, struct lustre_handle *lockh)
+/* returns a referenced lock or NULL */
+static struct ldlm_lock *search_queue(struct list_head *queue, ldlm_mode_t mode,
+                                      struct ldlm_extent *extent)
 {
+        struct ldlm_lock *lock;
         struct list_head *tmp;
 
         list_for_each(tmp, queue) {
-                struct ldlm_lock *lock;
                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 
-                if (lock->l_flags & LDLM_FL_DYING)
+                if (lock->l_flags & LDLM_FL_CBPENDING)
                         continue;
 
                 /* lock_convert() takes the resource lock, so we're sure that
@@ -428,23 +524,24 @@ static int search_queue(struct list_head *queue, ldlm_mode_t mode,
                      lock->l_extent.end < extent->end))
                         continue;
 
-                ldlm_lock_addref(lock, mode);
-                ldlm_object2handle(lock, lockh);
-                return 1;
+                ldlm_lock_addref_internal(lock, mode);
+                return lock;
         }
 
-        return 0;
+        return NULL;
 }
 
 /* Must be called with no resource or lock locks held.
  *
  * Returns 1 if it finds an already-existing lock that is compatible; in this
- * case, lockh is filled in with a addref()ed lock */
-int ldlm_local_lock_match(struct ldlm_namespace *ns, __u64 *res_id, __u32 type,
-                          void *cookie, int cookielen, ldlm_mode_t mode,
-                          struct lustre_handle *lockh)
+ * case, lockh is filled in with a addref()ed lock
+*/
+int ldlm_lock_match(struct ldlm_namespace *ns, __u64 * res_id, __u32 type,
+                    void *cookie, int cookielen, ldlm_mode_t mode,
+                    struct lustre_handle *lockh)
 {
         struct ldlm_resource *res;
+        struct ldlm_lock *lock;
         int rc = 0;
         ENTRY;
 
@@ -452,108 +549,92 @@ int ldlm_local_lock_match(struct ldlm_namespace *ns, __u64 *res_id, __u32 type,
         if (res == NULL)
                 RETURN(0);
 
-        spin_lock(&res->lr_lock);
-        if (search_queue(&res->lr_granted, mode, cookie, lockh))
+        ns = res->lr_namespace;
+        l_lock(&ns->ns_lock);
+
+        if ((lock = search_queue(&res->lr_granted, mode, cookie)))
                 GOTO(out, rc = 1);
-        if (search_queue(&res->lr_converting, mode, cookie, lockh))
+        if ((lock = search_queue(&res->lr_converting, mode, cookie)))
                 GOTO(out, rc = 1);
-        if (search_queue(&res->lr_waiting, mode, cookie, lockh))
+        if ((lock = search_queue(&res->lr_waiting, mode, cookie)))
                 GOTO(out, rc = 1);
 
         EXIT;
- out:
-        if (!ldlm_resource_put(res))
-                spin_unlock(&res->lr_lock);
+      out:
+        ldlm_resource_put(res);
+        l_unlock(&ns->ns_lock);
+
+        if (lock) {
+                ldlm_lock2handle(lock, lockh);
+                if (lock->l_completion_ast)
+                        lock->l_completion_ast(lock, LDLM_FL_WAIT_NOREPROC);
+        }
+        if (rc)
+                LDLM_DEBUG(lock, "matched");
+        else
+                LDLM_DEBUG_NOLOCK("not matched");
         return rc;
 }
 
-/* Must be called without the resource lock held.  Returns a referenced,
- * unlocked ldlm_lock. */
-ldlm_error_t ldlm_local_lock_create(struct ldlm_namespace *ns,
-                                    struct lustre_handle *parent_lock_handle,
-                                    __u64 *res_id, __u32 type,
-                                     ldlm_mode_t mode,
-                                    void *data,
-                                    __u32 data_len,
-                                    struct lustre_handle *lockh)
+/* Returns a referenced lock */
+struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
+                                   struct lustre_handle *parent_lock_handle,
+                                   __u64 * res_id, __u32 type,
+                                   ldlm_mode_t mode, void *data, __u32 data_len)
 {
         struct ldlm_resource *res, *parent_res = NULL;
         struct ldlm_lock *lock, *parent_lock;
 
-        parent_lock = lustre_handle2object(parent_lock_handle);
+        parent_lock = ldlm_handle2lock(parent_lock_handle);
         if (parent_lock)
                 parent_res = parent_lock->l_resource;
 
         res = ldlm_resource_get(ns, parent_res, res_id, type, 1);
         if (res == NULL)
-                RETURN(-ENOMEM);
+                RETURN(NULL);
 
         lock = ldlm_lock_new(parent_lock, res);
         if (lock == NULL) {
-                spin_lock(&res->lr_lock);
-                if (!ldlm_resource_put(res))
-                        spin_unlock(&res->lr_lock);
-                RETURN(-ENOMEM);
+                ldlm_resource_put(res);
+                RETURN(NULL);
         }
 
         lock->l_req_mode = mode;
         lock->l_data = data;
         lock->l_data_len = data_len;
-        ldlm_lock_addref(lock, mode);
 
-        ldlm_object2handle(lock, lockh);
-        return ELDLM_OK;
+        return lock;
 }
 
 /* Must be called with lock->l_lock and lock->l_resource->lr_lock not held */
-ldlm_error_t ldlm_local_lock_enqueue(struct lustre_handle *lockh,
-                                     void *cookie, int cookie_len,
-                                     int *flags,
-                                     ldlm_lock_callback completion,
-                                     ldlm_lock_callback blocking)
+ldlm_error_t ldlm_lock_enqueue(struct ldlm_lock * lock,
+                               void *cookie, int cookie_len,
+                               int *flags,
+                               ldlm_completion_callback completion,
+                               ldlm_blocking_callback blocking)
 {
         struct ldlm_resource *res;
-        struct ldlm_lock *lock;
-        int incompat = 0, local;
+        int local;
         ldlm_res_policy policy;
         ENTRY;
 
-        lock = lustre_handle2object(lockh);
         res = lock->l_resource;
-        local = res->lr_namespace->ns_client;
-        spin_lock(&res->lr_lock);
-
         lock->l_blocking_ast = blocking;
 
         if (res->lr_type == LDLM_EXTENT)
                 memcpy(&lock->l_extent, cookie, sizeof(lock->l_extent));
 
         /* policies are not executed on the client */
+        local = res->lr_namespace->ns_client;
         if (!local && (policy = ldlm_res_policy_table[res->lr_type])) {
                 int rc;
-
-                /* We do this dancing with refcounts and locks because the
-                 * policy function could send an RPC */
-                res->lr_refcount++;
-                spin_unlock(&res->lr_lock);
-
                 rc = policy(lock, cookie, lock->l_req_mode, NULL);
 
-                spin_lock(&res->lr_lock);
-                if (ldlm_resource_put(res))
-                        res = NULL;
-
                 if (rc == ELDLM_LOCK_CHANGED) {
-                        if (res)
-                                spin_unlock(&res->lr_lock);
                         res = lock->l_resource;
-                        spin_lock(&res->lr_lock);
                         *flags |= LDLM_FL_LOCK_CHANGED;
                 } else if (rc == ELDLM_LOCK_ABORTED) {
-                        /* Abort. */
-                        if (res && !ldlm_resource_put(res))
-                                spin_unlock(&res->lr_lock);
-                        ldlm_lock_free(lock);
+                        ldlm_lock_destroy(lock);
                         RETURN(rc);
                 }
         }
@@ -565,11 +646,15 @@ ldlm_error_t ldlm_local_lock_enqueue(struct lustre_handle *lockh,
                 /* The server returned a blocked lock, but it was granted before
                  * we got a chance to actually enqueue it.  We don't need to do
                  * anything else. */
-                GOTO(out_noput, ELDLM_OK);
+                GOTO(out, ELDLM_OK);
         }
 
-        /* If this is a local resource, put it on the appropriate list. */
-        list_del_init(&lock->l_res_link);
+        /* This distinction between local lock trees is very important; a client
+         * namespace only has information about locks taken by that client, and
+         * thus doesn't have enough information to decide for itself if it can
+         * be granted (below).  In this case, we do exactly what the server
+         * tells us to do, as dictated by the 'flags' */
+        ldlm_resource_unlink_lock(lock);
         if (local) {
                 if (*flags & LDLM_FL_BLOCK_CONV)
                         ldlm_resource_add_lock(res, res->lr_converting.prev,
@@ -577,7 +662,7 @@ ldlm_error_t ldlm_local_lock_enqueue(struct lustre_handle *lockh,
                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
                         ldlm_resource_add_lock(res, res->lr_waiting.prev, lock);
                 else
-                        ldlm_grant_lock(res, lock);
+                        ldlm_grant_lock(lock);
                 GOTO(out, ELDLM_OK);
         }
 
@@ -592,74 +677,66 @@ ldlm_error_t ldlm_local_lock_enqueue(struct lustre_handle *lockh,
                 *flags |= LDLM_FL_BLOCK_WAIT;
                 GOTO(out, ELDLM_OK);
         }
-        incompat = ldlm_lock_compat(lock, 0);
-        if (incompat) {
+        if (!ldlm_lock_compat(lock, 0)) {
                 ldlm_resource_add_lock(res, res->lr_waiting.prev, lock);
                 *flags |= LDLM_FL_BLOCK_GRANTED;
                 GOTO(out, ELDLM_OK);
         }
 
-        ldlm_grant_lock(res, lock);
+        ldlm_grant_lock(lock);
         EXIT;
- out:
-        /* We're called with a lock that has a referenced resource and is not on
-         * any resource list.  When we added it to a list, we incurred an extra
-         * reference. */
-        if (ldlm_resource_put(lock->l_resource))
-                res = NULL;
- out_noput:
+      out:
         /* Don't set 'completion_ast' until here so that if the lock is granted
          * immediately we don't do an unnecessary completion call. */
         lock->l_completion_ast = completion;
-        if (res)
-                spin_unlock(&res->lr_lock);
         return ELDLM_OK;
 }
 
-/* Must be called with resource->lr_lock taken. */
+/* Must be called with namespace taken: queue is waiting or converting. */
 static int ldlm_reprocess_queue(struct ldlm_resource *res,
-                                struct list_head *converting)
+                                struct list_head *queue)
 {
         struct list_head *tmp, *pos;
         ENTRY;
 
-        list_for_each_safe(tmp, pos, converting) {
+        list_for_each_safe(tmp, pos, queue) {
                 struct ldlm_lock *pending;
                 pending = list_entry(tmp, struct ldlm_lock, l_res_link);
 
                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
 
-                /* the resource lock protects ldlm_lock_compat */
-                if (ldlm_lock_compat(pending, 1))
+                if (!ldlm_lock_compat(pending, 1))
                         RETURN(1);
 
                 list_del_init(&pending->l_res_link);
-                ldlm_grant_lock(res, pending);
-
-                ldlm_lock_addref(pending, pending->l_req_mode);
-                ldlm_lock_decref(pending, pending->l_granted_mode);
+                ldlm_grant_lock(pending);
         }
 
         RETURN(0);
 }
 
-static void ldlm_send_delayed_asts(struct list_head *rpc_list)
+void ldlm_run_ast_work(struct list_head *rpc_list)
 {
         struct list_head *tmp, *pos;
+        int rc;
         ENTRY;
 
         list_for_each_safe(tmp, pos, rpc_list) {
-                int rc;
-                struct ptlrpc_request *req =
-                        list_entry(tmp, struct ptlrpc_request, rq_multi);
-
-                CDEBUG(D_INFO, "Sending callback.\n");
+                struct ldlm_ast_work *w =
+                        list_entry(tmp, struct ldlm_ast_work, w_list);
 
-                rc = ptlrpc_queue_wait(req);
-                rc = ptlrpc_check_status(req, rc);
-                ptlrpc_free_req(req);
+                if (w->w_blocking)
+                        rc = w->w_lock->l_blocking_ast
+                                (w->w_lock, &w->w_desc, w->w_data,
+                                 w->w_datalen);
+                else
+                        rc = w->w_lock->l_completion_ast(w->w_lock, w->w_flags);
                 if (rc)
-                        CERROR("Callback send failed: %d\n", rc);
+                        CERROR("Failed AST - should clean & disconnect "
+                               "client\n");
+                LDLM_LOCK_PUT(w->w_lock);
+                list_del(&w->w_list);
+                OBD_FREE(w, sizeof(*w));
         }
         EXIT;
 }
@@ -676,7 +753,7 @@ void ldlm_reprocess_all(struct ldlm_resource *res)
                 return;
         }
 
-        spin_lock(&res->lr_lock);
+        l_lock(&res->lr_namespace->ns_lock);
         res->lr_tmp = &rpc_list;
 
         ldlm_reprocess_queue(res, &res->lr_converting);
@@ -684,67 +761,70 @@ void ldlm_reprocess_all(struct ldlm_resource *res)
                 ldlm_reprocess_queue(res, &res->lr_waiting);
 
         res->lr_tmp = NULL;
-        spin_unlock(&res->lr_lock);
+        l_unlock(&res->lr_namespace->ns_lock);
 
-        ldlm_send_delayed_asts(&rpc_list);
+        ldlm_run_ast_work(&rpc_list);
         EXIT;
 }
 
-/* Must be called with lock and lock->l_resource unlocked */
-struct ldlm_resource *ldlm_local_lock_cancel(struct ldlm_lock *lock)
+void ldlm_lock_cancel(struct ldlm_lock *lock)
 {
         struct ldlm_resource *res;
+        struct ldlm_namespace *ns;
         ENTRY;
 
         res = lock->l_resource;
+        ns = res->lr_namespace;
 
-        spin_lock(&res->lr_lock);
-        spin_lock(&lock->l_lock);
-
+        l_lock(&ns->ns_lock);
         if (lock->l_readers || lock->l_writers)
                 CDEBUG(D_INFO, "lock still has references (%d readers, %d "
                        "writers)\n", lock->l_readers, lock->l_writers);
 
-        if (ldlm_resource_del_lock(lock))
-                res = NULL; /* res was freed, nothing else to do. */
-        else
-                spin_unlock(&res->lr_lock);
-        ldlm_lock_free(lock);
-
-        RETURN(res);
+        ldlm_resource_unlink_lock(lock);
+        ldlm_lock_destroy(lock);
+        l_unlock(&ns->ns_lock);
+        EXIT;
 }
 
-/* Must be called with lock and lock->l_resource unlocked */
-struct ldlm_resource *ldlm_local_lock_convert(struct lustre_handle *lockh,
-                                              int new_mode, int *flags)
+struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
+                                        int *flags)
 {
-        struct ldlm_lock *lock;
+        struct list_head rpc_list = LIST_HEAD_INIT(rpc_list);
         struct ldlm_resource *res;
+        struct ldlm_namespace *ns;
+        int granted = 0;
         ENTRY;
 
-        lock = lustre_handle2object(lockh);
         res = lock->l_resource;
+        ns = res->lr_namespace;
 
-        spin_lock(&res->lr_lock);
+        l_lock(&ns->ns_lock);
 
         lock->l_req_mode = new_mode;
-        list_del_init(&lock->l_res_link);
+        ldlm_resource_unlink_lock(lock);
 
         /* If this is a local resource, put it on the appropriate list. */
         if (res->lr_namespace->ns_client) {
-                if (*flags & LDLM_FL_BLOCK_CONV)
+                if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED))
                         ldlm_resource_add_lock(res, res->lr_converting.prev,
                                                lock);
-                else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
-                        ldlm_resource_add_lock(res, res->lr_waiting.prev, lock);
-                else
-                        ldlm_grant_lock(res, lock);
-        } else {
-                list_add(&lock->l_res_link, res->lr_converting.prev);
-        }
+                else {
+                        res->lr_tmp = &rpc_list;
+                        ldlm_grant_lock(lock);
+                        res->lr_tmp = NULL;
+                        granted = 1;
+                        /* FIXME: completion handling not with ns_lock held ! */
+                        if (lock->l_completion_ast)
+                                lock->l_completion_ast(lock, 0);
+                }
+        } else
+                list_add_tail(&lock->l_res_link, &res->lr_converting);
 
-        spin_unlock(&res->lr_lock);
+        l_unlock(&ns->ns_lock);
 
+        if (granted)
+                ldlm_run_ast_work(&rpc_list);
         RETURN(res);
 }
 
@@ -768,6 +848,12 @@ void ldlm_lock_dump(struct ldlm_lock *lock)
                  lock->l_version[2], lock->l_version[3]);
 
         CDEBUG(D_OTHER, "  -- Lock dump: %p (%s)\n", lock, ver);
+        if (lock->l_export && lock->l_export->exp_connection)
+                CDEBUG(D_OTHER, "  Node: NID %x (rhandle: %Lx)\n",
+                       lock->l_export->exp_connection->c_peer.peer_nid,
+                       lock->l_remote_handle.addr);
+        else
+                CDEBUG(D_OTHER, "  Node: local\n");
         CDEBUG(D_OTHER, "  Parent: %p\n", lock->l_parent);
         CDEBUG(D_OTHER, "  Resource: %p (%Ld)\n", lock->l_resource,
                lock->l_resource->lr_name[0]);