1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Copyright (c) 2002, 2003, 2004 Cluster File Systems, Inc.
5 * Author: Peter Braam <braam@clusterfs.com>
6 * Author: Phil Schwan <phil@clusterfs.com>
8 * This file is part of Lustre, http://www.lustre.org.
10 * Lustre is free software; you can redistribute it and/or
11 * modify it under the terms of version 2 of the GNU General Public
12 * License as published by the Free Software Foundation.
14 * Lustre is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with Lustre; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #define DEBUG_SUBSYSTEM S_LDLM
26 # include <liblustre.h>
29 #include <lustre_dlm.h>
30 #include <obd_support.h>
31 #include <lustre_lib.h>
33 #include "ldlm_internal.h"
35 /* Determine if the lock is compatible with all locks on the queue. */
37 ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req,
38 struct list_head *work_list)
40 struct list_head *tmp, *tmp_tail;
41 struct ldlm_lock *lock;
42 ldlm_mode_t req_mode = req->l_req_mode;
43 __u64 req_bits = req->l_policy_data.l_inodebits.bits;
47 LASSERT(req_bits); /* There is no sense in lock with no bits set,
48 I think. Also such a lock would be compatible
49 with any other bit lock */
50 list_for_each(tmp, queue) {
51 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
56 /* locks are compatible, bits don't matter */
57 if (lockmode_compat(lock->l_req_mode, req_mode)) {
58 /* jump to next mode group */
59 if (LDLM_SL_HEAD(&lock->l_sl_mode))
60 tmp = &list_entry(lock->l_sl_mode.next,
62 l_sl_mode)->l_res_link;
67 if (LDLM_SL_HEAD(&lock->l_sl_mode))
68 tmp_tail = &list_entry(lock->l_sl_mode.next,
70 l_sl_mode)->l_res_link;
72 /* locks with bits overlapped are conflicting locks */
73 if (lock->l_policy_data.l_inodebits.bits & req_bits) {
74 /* conflicting policy */
79 if (lock->l_blocking_ast)
80 ldlm_add_ast_work_item(lock, req,
82 /* add all members of the policy group */
83 if (LDLM_SL_HEAD(&lock->l_sl_policy)) {
85 tmp = lock->l_res_link.next;
86 lock = list_entry(tmp,
89 if (lock->l_blocking_ast)
90 ldlm_add_ast_work_item(
94 } while (!LDLM_SL_TAIL(&lock->l_sl_policy));
96 } else if (LDLM_SL_HEAD(&lock->l_sl_policy)) {
97 /* jump to next policy group */
98 tmp = &list_entry(lock->l_sl_policy.next,
100 l_sl_policy)->l_res_link;
106 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
107 } /* for locks in a mode group */
108 } /* for each lock in the queue */
113 /* If first_enq is 0 (ie, called from ldlm_reprocess_queue):
114 * - blocking ASTs have already been sent
115 * - must call this function with the ns lock held
117 * If first_enq is 1 (ie, called from ldlm_lock_enqueue):
118 * - blocking ASTs have not been sent
119 * - must call this function with the ns lock held once */
120 int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags,
121 int first_enq, ldlm_error_t *err,
122 struct list_head *work_list)
124 struct ldlm_resource *res = lock->l_resource;
125 struct list_head rpc_list = CFS_LIST_HEAD_INIT(rpc_list);
129 LASSERT(list_empty(&res->lr_converting));
130 check_res_locked(res);
133 LASSERT(work_list != NULL);
134 rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, NULL);
136 RETURN(LDLM_ITER_STOP);
137 rc = ldlm_inodebits_compat_queue(&res->lr_waiting, lock, NULL);
139 RETURN(LDLM_ITER_STOP);
141 ldlm_resource_unlink_lock(lock);
142 ldlm_grant_lock(lock, work_list);
143 RETURN(LDLM_ITER_CONTINUE);
147 rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, &rpc_list);
148 rc += ldlm_inodebits_compat_queue(&res->lr_waiting, lock, &rpc_list);
151 /* If either of the compat_queue()s returned 0, then we
152 * have ASTs to send and must go onto the waiting list.
154 * bug 2322: we used to unlink and re-add here, which was a
155 * terrible folly -- if we goto restart, we could get
156 * re-ordered! Causes deadlock, because ASTs aren't sent! */
157 if (list_empty(&lock->l_res_link))
158 ldlm_resource_add_lock(res, &res->lr_waiting, lock);
160 rc = ldlm_run_bl_ast_work(&rpc_list);
163 GOTO(restart, -ERESTART);
164 *flags |= LDLM_FL_BLOCK_GRANTED;
166 ldlm_resource_unlink_lock(lock);
167 ldlm_grant_lock(lock, NULL);