X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Fldlm%2Fl_lock.c;h=a4f7c85a42efb8352f353d67e0d5fc5b47ee1e98;hb=7525fd36a26631e4a5668e53f44e39ed600eea08;hp=680d4f0521e359f79c25aef8b10cdf74e7bb2d73;hpb=7312616768bfed768ecc00ba20322c37568138d0;p=fs%2Flustre-release.git

diff --git a/lustre/ldlm/l_lock.c b/lustre/ldlm/l_lock.c
index 680d4f0..a4f7c85 100644
--- a/lustre/ldlm/l_lock.c
+++ b/lustre/ldlm/l_lock.c
@@ -1,108 +1,72 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
  *
- * Copyright (C) 2001, 2002 Cluster File Systems, Inc.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
- *   This file is part of Lustre, http://www.sf.net/projects/lustre/
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
  *
- *   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.
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
  *
- *   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
+ * version 2 along with this program; If not, see
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
- *   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.
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
  *
+ * Copyright (c) 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
  */
-
-#include <linux/config.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/stat.h>
-#include <linux/errno.h>
-#include <linux/unistd.h>
-#include <linux/version.h>
-
-#include <asm/system.h>
-#include <asm/uaccess.h>
-
-#include <linux/fs.h>
-#include <linux/stat.h>
-#include <asm/uaccess.h>
-#include <asm/segment.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/smp_lock.h>
 
 #define DEBUG_SUBSYSTEM S_LDLM
+#include <libcfs/libcfs.h>
 
-#include <linux/obd_class.h>
-#include <linux/lustre_lib.h>
-
-/* invariants:
- - only the owner of the lock changes l_owner/l_depth
- - if a non-owner changes or checks the variables a spin lock is taken
-*/
-
-void l_lock_init(struct lustre_lock *lock)
-{
-        sema_init(&lock->l_sem, 1);
-        spin_lock_init(&lock->l_spin);
-}
+#include <lustre_dlm.h>
+#include <lustre_lib.h>
 
-void l_lock(struct lustre_lock *lock)
+/**
+ * Lock a lock and its resource.
+ *
+ * LDLM locking uses resource to serialize access to locks
+ * but there is a case when we change resource of lock upon
+ * enqueue reply. We rely on lock->l_resource = new_res
+ * being an atomic operation.
+ */
+struct ldlm_resource *lock_res_and_lock(struct ldlm_lock *lock)
 {
-        int owner = 0;
-
-        spin_lock(&lock->l_spin);
-        if (lock->l_owner == current)
-                owner = 1;
-        spin_unlock(&lock->l_spin);
-
-        if (owner) {
-                ++lock->l_depth;
-        } else {
-                down(&lock->l_sem);
-                spin_lock(&lock->l_spin);
-                lock->l_owner = current;
-                lock->l_depth = 0;
-                spin_unlock(&lock->l_spin);
-        }
-}
+	/* on server-side resource of lock doesn't change */
+	if (!ldlm_is_ns_srv(lock))
+		spin_lock(&lock->l_lock);
 
-void l_unlock(struct lustre_lock *lock)
-{
-        LASSERT(lock->l_owner == current);
-        LASSERT(lock->l_depth >= 0);
+	lock_res(lock->l_resource);
 
-        spin_lock(&lock->l_spin);
-        if (--lock->l_depth < 0) {
-                lock->l_owner = NULL;
-                spin_unlock(&lock->l_spin);
-                up(&lock->l_sem);
-                return;
-        }
-        spin_unlock(&lock->l_spin);
+	ldlm_set_res_locked(lock);
+	return lock->l_resource;
 }
+EXPORT_SYMBOL(lock_res_and_lock);
 
-int l_has_lock(struct lustre_lock *lock)
+/**
+ * Unlock a lock and its resource previously locked with lock_res_and_lock
+ */
+void unlock_res_and_lock(struct ldlm_lock *lock)
 {
-        int depth = -1, owner = 0;
-
-        spin_lock(&lock->l_spin);
-        if (lock->l_owner == current) {
-                depth = lock->l_depth;
-                owner = 1;
-        }
-        spin_unlock(&lock->l_spin);
+	/* on server-side resource of lock doesn't change */
+	ldlm_clear_res_locked(lock);
 
-        if (depth >= 0)
-                CDEBUG(D_INFO, "lock_depth: %d\n", depth);
-        return owner;
+	unlock_res(lock->l_resource);
+	if (!ldlm_is_ns_srv(lock))
+		spin_unlock(&lock->l_lock);
 }
+EXPORT_SYMBOL(unlock_res_and_lock);