-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
*
- * Copyright (c) 2002, 2003, 2004 Cluster File Systems, Inc.
- * Author: Peter Braam <braam@clusterfs.com>
- * Author: Phil Schwan <phil@clusterfs.com>
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
- * This file is part of Lustre, http://www.lustre.org.
+ * 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.sun.com/software/products/lustre/docs/GPLv2.pdf
*
- * 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.
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2013, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * lustre/ldlm/ldlm_inodebits.c
+ *
+ * Author: Peter Braam <braam@clusterfs.com>
+ * Author: Phil Schwan <phil@clusterfs.com>
+ */
+
+/**
+ * This file contains implementation of IBITS lock type
+ *
+ * IBITS lock type contains a bit mask determining various properties of an
+ * object. The meanings of specific bits are specific to the caller and are
+ * opaque to LDLM code.
+ *
+ * Locks with intersecting bitmasks and conflicting lock modes (e.g. LCK_PW)
+ * are considered conflicting. See the lock mode compatibility matrix
+ * in lustre_dlm.h.
*/
#define DEBUG_SUBSYSTEM S_LDLM
# include <liblustre.h>
#endif
-#include <linux/lustre_dlm.h>
-#include <linux/obd_support.h>
-#include <linux/lustre_lib.h>
+#include <lustre_dlm.h>
+#include <obd_support.h>
+#include <lustre_lib.h>
#include "ldlm_internal.h"
-/* Determine if the lock is compatible with all locks on the queue. */
+#ifdef HAVE_SERVER_SUPPORT
+/**
+ * Determine if the lock is compatible with all locks on the queue.
+ *
+ * If \a work_list is provided, conflicting locks are linked there.
+ * If \a work_list is not provided, we exit this function on first conflict.
+ *
+ * \retval 0 if there are conflicting locks in the \a queue
+ * \retval 1 if the lock is compatible to all locks in \a queue
+ *
+ * IBITS locks in granted queue are organized in bunches of
+ * same-mode/same-bits locks called "skip lists". The First lock in the
+ * bunch contains a pointer to the end of the bunch. This allows us to
+ * skip an entire bunch when iterating the list in search for conflicting
+ * locks if first lock of the bunch is not conflicting with us.
+ */
static int
-ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req,
- struct list_head *work_list)
+ldlm_inodebits_compat_queue(cfs_list_t *queue, struct ldlm_lock *req,
+ cfs_list_t *work_list)
{
- struct list_head *tmp;
+ cfs_list_t *tmp;
struct ldlm_lock *lock;
ldlm_mode_t req_mode = req->l_req_mode;
__u64 req_bits = req->l_policy_data.l_inodebits.bits;
int compat = 1;
ENTRY;
- LASSERT(req_bits); /* There is no sence in lock with no bits set,
+ LASSERT(req_bits); /* There is no sense in lock with no bits set,
I think. Also such a lock would be compatible
with any other bit lock */
- list_for_each(tmp, queue) {
- lock = list_entry(tmp, struct ldlm_lock, l_res_link);
+ cfs_list_for_each(tmp, queue) {
+ cfs_list_t *mode_tail;
+
+ lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
+
+ /* We stop walking the queue if we hit ourselves so we don't
+ * take conflicting locks enqueued after us into account,
+ * or we'd wait forever. */
if (req == lock)
RETURN(compat);
- /* locks are compatible, bits don't matter */
- if (lockmode_compat(lock->l_req_mode, req_mode))
- continue;
+ /* last lock in mode group */
+ LASSERT(lock->l_sl_mode.prev != NULL);
+ mode_tail = &cfs_list_entry(lock->l_sl_mode.prev,
+ struct ldlm_lock,
+ l_sl_mode)->l_res_link;
- /* if bits don't overlap skip it */
- if (!(lock->l_policy_data.l_inodebits.bits & req_bits))
+ /* locks are compatible, bits don't matter */
+ if (lockmode_compat(lock->l_req_mode, req_mode)) {
+ /* jump to last lock in mode group */
+ tmp = mode_tail;
continue;
-
- if (!work_list)
- RETURN(0);
-
- compat = 0;
- if (lock->l_blocking_ast)
- ldlm_add_ast_work_item(lock, req, work_list);
- }
-
- RETURN(compat);
+ }
+
+ for (;;) {
+ cfs_list_t *head;
+
+ /* Advance loop cursor to last lock in policy group. */
+ tmp = &cfs_list_entry(lock->l_sl_policy.prev,
+ struct ldlm_lock,
+ l_sl_policy)->l_res_link;
+
+ /* Locks with overlapping bits conflict. */
+ if (lock->l_policy_data.l_inodebits.bits & req_bits) {
+ /* COS lock mode has a special compatibility
+ * requirement: it is only compatible with
+ * locks from the same client. */
+ if (lock->l_req_mode == LCK_COS &&
+ lock->l_client_cookie == req->l_client_cookie)
+ goto not_conflicting;
+ /* Found a conflicting policy group. */
+ if (!work_list)
+ RETURN(0);
+
+ compat = 0;
+
+ /* Add locks of the policy group to @work_list
+ * as blocking locks for @req */
+ if (lock->l_blocking_ast)
+ ldlm_add_ast_work_item(lock, req,
+ work_list);
+ head = &lock->l_sl_policy;
+ cfs_list_for_each_entry(lock, head, l_sl_policy)
+ if (lock->l_blocking_ast)
+ ldlm_add_ast_work_item(lock, req,
+ work_list);
+ }
+ not_conflicting:
+ if (tmp == mode_tail)
+ break;
+
+ tmp = tmp->next;
+ lock = cfs_list_entry(tmp, struct ldlm_lock,
+ l_res_link);
+ } /* Loop over policy groups within one mode group. */
+ } /* Loop over mode groups within @queue. */
+
+ RETURN(compat);
}
-/* If first_enq is 0 (ie, called from ldlm_reprocess_queue):
- * - blocking ASTs have already been sent
- * - the caller has already initialized req->lr_tmp
- * - must call this function with the ns lock held
- *
- * If first_enq is 1 (ie, called from ldlm_lock_enqueue):
- * - blocking ASTs have not been sent
- * - the caller has NOT initialized req->lr_tmp, so we must
- * - must call this function with the ns lock held once */
-int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags,
+/**
+ * Process a granting attempt for IBITS lock.
+ * Must be called with ns lock held
+ *
+ * This function looks for any conflicts for \a lock in the granted or
+ * waiting queues. The lock is granted if no conflicts are found in
+ * either queue.
+ *
+ * If \a first_enq is 0 (ie, called from ldlm_reprocess_queue):
+ * - blocking ASTs have already been sent
+ *
+ * If \a first_enq is 1 (ie, called from ldlm_lock_enqueue):
+ * - blocking ASTs have not been sent yet, so list of conflicting locks
+ * would be collected and ASTs sent.
+ */
+int ldlm_process_inodebits_lock(struct ldlm_lock *lock, __u64 *flags,
int first_enq, ldlm_error_t *err,
- struct list_head *work_list)
+ cfs_list_t *work_list)
{
struct ldlm_resource *res = lock->l_resource;
- struct list_head rpc_list = LIST_HEAD_INIT(rpc_list);
+ CFS_LIST_HEAD(rpc_list);
int rc;
ENTRY;
- LASSERT(list_empty(&res->lr_converting));
+ LASSERT(cfs_list_empty(&res->lr_converting));
check_res_locked(res);
- if (!first_enq) {
- LASSERT(work_list != NULL);
+ /* (*flags & LDLM_FL_BLOCK_NOWAIT) is for layout lock right now. */
+ if (!first_enq || (*flags & LDLM_FL_BLOCK_NOWAIT)) {
+ *err = ELDLM_LOCK_ABORTED;
+ if (*flags & LDLM_FL_BLOCK_NOWAIT)
+ *err = ELDLM_LOCK_WOULDBLOCK;
+
rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, NULL);
if (!rc)
RETURN(LDLM_ITER_STOP);
ldlm_resource_unlink_lock(lock);
ldlm_grant_lock(lock, work_list);
+
+ *err = ELDLM_OK;
RETURN(LDLM_ITER_CONTINUE);
}
* bug 2322: we used to unlink and re-add here, which was a
* terrible folly -- if we goto restart, we could get
* re-ordered! Causes deadlock, because ASTs aren't sent! */
- if (list_empty(&lock->l_res_link))
+ if (cfs_list_empty(&lock->l_res_link))
ldlm_resource_add_lock(res, &res->lr_waiting, lock);
unlock_res(res);
- rc = ldlm_run_bl_ast_work(&rpc_list);
+ rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list,
+ LDLM_WORK_BL_AST);
lock_res(res);
- if (rc == -ERESTART)
- GOTO(restart, -ERESTART);
+ if (rc == -ERESTART)
+ GOTO(restart, rc);
*flags |= LDLM_FL_BLOCK_GRANTED;
} else {
ldlm_resource_unlink_lock(lock);
}
RETURN(0);
}
+#endif /* HAVE_SERVER_SUPPORT */
+
+void ldlm_ibits_policy_wire_to_local(const ldlm_wire_policy_data_t *wpolicy,
+ ldlm_policy_data_t *lpolicy)
+{
+ memset(lpolicy, 0, sizeof(*lpolicy));
+ lpolicy->l_inodebits.bits = wpolicy->l_inodebits.bits;
+}
+
+void ldlm_ibits_policy_local_to_wire(const ldlm_policy_data_t *lpolicy,
+ ldlm_wire_policy_data_t *wpolicy)
+{
+ memset(wpolicy, 0, sizeof(*wpolicy));
+ wpolicy->l_inodebits.bits = lpolicy->l_inodebits.bits;
+}