*
* Copyright (C) 2001, 2002 Cluster File Systems, Inc.
*
- * This file is part of Lustre, http://www.sf.net/projects/lustre/
+ * This file is part of the Lustre file system, http://www.lustre.org
+ * Lustre is a trademark of Cluster File Systems, Inc.
*
- * 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.
+ * You may have signed or agreed to another license before downloading
+ * this software. If so, you are bound by the terms and conditions
+ * of that agreement, and the following does not apply to you. See the
+ * LICENSE file included with this distribution for more information.
*
- * 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.
+ * If you did not agree to a different license, then this copy of Lustre
+ * is open source 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.
*
- * 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.
+ * In either case, 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
+ * license text for more details.
*
*/
#define DEBUG_SUBSYSTEM S_LDLM
#ifdef __KERNEL__
-#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>
+#include <libcfs/libcfs.h>
#else
#include <liblustre.h>
#endif
-#include <linux/lustre_dlm.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
-*/
+#include <lustre_dlm.h>
+#include <lustre_lib.h>
-void l_lock_init(struct lustre_lock *lock)
+/*
+ * 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 that lock->l_resource = new_res
+ * is atomic
+ */
+struct ldlm_resource * lock_res_and_lock(struct ldlm_lock *lock)
{
- sema_init(&lock->l_sem, 1);
- spin_lock_init(&lock->l_spin);
+ struct ldlm_resource *res = lock->l_resource;
+
+ if (ns_is_server(res->lr_namespace)) {
+ /* on server-side resource of lock doesn't change */
+ lock_res(res);
+ return res;
+ }
+
+ spin_lock(&lock->l_lock);
+ res = lock->l_resource;
+ lock_res(res);
+ return res;
}
-void l_lock(struct lustre_lock *lock)
+void unlock_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);
-
- /* This is safe to increment outside the spinlock because we
- * can only have 1 CPU running on the current task
- * (i.e. l_owner == current), regardless of the number of CPUs.
- */
- 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);
- }
-}
+ struct ldlm_resource *res = lock->l_resource;
-void l_unlock(struct lustre_lock *lock)
-{
- LASSERTF(lock->l_owner == current, "lock %p, current %p\n",
- lock->l_owner, current);
- LASSERTF(lock->l_depth >= 0, "depth %d\n", lock->l_depth);
- spin_lock(&lock->l_spin);
- if (--lock->l_depth < 0) {
- lock->l_owner = NULL;
- spin_unlock(&lock->l_spin);
- up(&lock->l_sem);
+ if (ns_is_server(res->lr_namespace)) {
+ /* on server-side resource of lock doesn't change */
+ unlock_res(res);
return;
}
- spin_unlock(&lock->l_spin);
-}
-
-int l_has_lock(struct lustre_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);
-
- if (depth >= 0)
- CDEBUG(D_INFO, "lock_depth: %d\n", depth);
- return owner;
+ unlock_res(res);
+ spin_unlock(&lock->l_lock);
}
-#ifdef __KERNEL__
-#include <linux/lustre_version.h>
-void l_check_no_ns_lock(struct ldlm_namespace *ns)
-{
- static unsigned long next_msg;
-
- if (l_has_lock(&ns->ns_lock) && time_after(jiffies, next_msg)) {
- CERROR("namespace %s lock held illegally; tell phil\n",
- ns->ns_name);
- portals_debug_dumpstack(NULL);
- next_msg = jiffies + 60 * HZ;
- }
-}
-
-#else
-void l_check_no_ns_lock(struct ldlm_namespace *ns)
-{
- if (l_has_lock(&ns->ns_lock)) {
- CERROR("namespace %s lock held illegally; tell phil\n",
- ns->ns_name);
- }
-}
-#endif /* __KERNEL__ */
git://git.whamcloud.com / fs / lustre-release.git / blobdiff