4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2011, 2012, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
34 * Author: Nikita Danilov <nikita.danilov@sun.com>
35 * Author: Jinshan Xiong <jinshan.xiong@intel.com>
38 #define DEBUG_SUBSYSTEM S_CLASS
40 #include "../include/obd_class.h"
41 #include "../include/obd_support.h"
42 #include "../include/lustre_fid.h"
43 #include <linux/list.h>
44 #include "../include/cl_object.h"
45 #include "cl_internal.h"
47 static void cl_lock_trace0(int level, const struct lu_env *env,
48 const char *prefix, const struct cl_lock *lock,
49 const char *func, const int line)
51 struct cl_object_header *h = cl_object_header(lock->cll_descr.cld_obj);
53 CDEBUG(level, "%s: %p (%p/%d) at %s():%d\n",
54 prefix, lock, env, h->coh_nesting, func, line);
56 #define cl_lock_trace(level, env, prefix, lock) \
57 cl_lock_trace0(level, env, prefix, lock, __func__, __LINE__)
60 * Adds lock slice to the compound lock.
62 * This is called by cl_object_operations::coo_lock_init() methods to add a
63 * per-layer state to the lock. New state is added at the end of
64 * cl_lock::cll_layers list, that is, it is at the bottom of the stack.
66 * \see cl_req_slice_add(), cl_page_slice_add(), cl_io_slice_add()
68 void cl_lock_slice_add(struct cl_lock *lock, struct cl_lock_slice *slice,
69 struct cl_object *obj,
70 const struct cl_lock_operations *ops)
72 slice->cls_lock = lock;
73 list_add_tail(&slice->cls_linkage, &lock->cll_layers);
77 EXPORT_SYMBOL(cl_lock_slice_add);
79 void cl_lock_fini(const struct lu_env *env, struct cl_lock *lock)
81 cl_lock_trace(D_DLMTRACE, env, "destroy lock", lock);
83 while (!list_empty(&lock->cll_layers)) {
84 struct cl_lock_slice *slice;
86 slice = list_entry(lock->cll_layers.next,
87 struct cl_lock_slice, cls_linkage);
88 list_del_init(lock->cll_layers.next);
89 slice->cls_ops->clo_fini(env, slice);
91 POISON(lock, 0x5a, sizeof(*lock));
93 EXPORT_SYMBOL(cl_lock_fini);
95 int cl_lock_init(const struct lu_env *env, struct cl_lock *lock,
96 const struct cl_io *io)
98 struct cl_object *obj = lock->cll_descr.cld_obj;
99 struct cl_object *scan;
102 /* Make sure cl_lock::cll_descr is initialized. */
105 INIT_LIST_HEAD(&lock->cll_layers);
106 list_for_each_entry(scan, &obj->co_lu.lo_header->loh_layers,
108 result = scan->co_ops->coo_lock_init(env, scan, lock, io);
110 cl_lock_fini(env, lock);
117 EXPORT_SYMBOL(cl_lock_init);
120 * Returns a slice with a lock, corresponding to the given layer in the
125 const struct cl_lock_slice *cl_lock_at(const struct cl_lock *lock,
126 const struct lu_device_type *dtype)
128 const struct cl_lock_slice *slice;
130 list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
131 if (slice->cls_obj->co_lu.lo_dev->ld_type == dtype)
136 EXPORT_SYMBOL(cl_lock_at);
138 void cl_lock_cancel(const struct lu_env *env, struct cl_lock *lock)
140 const struct cl_lock_slice *slice;
142 cl_lock_trace(D_DLMTRACE, env, "cancel lock", lock);
143 list_for_each_entry_reverse(slice, &lock->cll_layers, cls_linkage) {
144 if (slice->cls_ops->clo_cancel)
145 slice->cls_ops->clo_cancel(env, slice);
148 EXPORT_SYMBOL(cl_lock_cancel);
152 * \param anchor: if we need to wait for resources before getting the lock,
153 * use @anchor for the purpose.
154 * \retval 0 enqueue successfully
155 * \retval <0 error code
157 int cl_lock_enqueue(const struct lu_env *env, struct cl_io *io,
158 struct cl_lock *lock, struct cl_sync_io *anchor)
160 const struct cl_lock_slice *slice;
163 list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
164 if (!slice->cls_ops->clo_enqueue)
167 rc = slice->cls_ops->clo_enqueue(env, slice, io, anchor);
173 EXPORT_SYMBOL(cl_lock_enqueue);
176 * Main high-level entry point of cl_lock interface that finds existing or
177 * enqueues new lock matching given description.
179 int cl_lock_request(const struct lu_env *env, struct cl_io *io,
180 struct cl_lock *lock)
182 struct cl_sync_io *anchor = NULL;
183 __u32 enq_flags = lock->cll_descr.cld_enq_flags;
186 rc = cl_lock_init(env, lock, io);
190 if ((enq_flags & CEF_ASYNC) && !(enq_flags & CEF_AGL)) {
191 anchor = &cl_env_info(env)->clt_anchor;
192 cl_sync_io_init(anchor, 1, cl_sync_io_end);
195 rc = cl_lock_enqueue(env, io, lock, anchor);
200 /* drop the reference count held at initialization time */
201 cl_sync_io_note(env, anchor, 0);
202 rc2 = cl_sync_io_wait(env, anchor, 0);
203 if (rc2 < 0 && rc == 0)
208 cl_lock_release(env, lock);
212 EXPORT_SYMBOL(cl_lock_request);
215 * Releases a hold and a reference on a lock, obtained by cl_lock_hold().
217 void cl_lock_release(const struct lu_env *env, struct cl_lock *lock)
219 cl_lock_trace(D_DLMTRACE, env, "release lock", lock);
220 cl_lock_cancel(env, lock);
221 cl_lock_fini(env, lock);
223 EXPORT_SYMBOL(cl_lock_release);
225 const char *cl_lock_mode_name(const enum cl_lock_mode mode)
227 static const char *names[] = {
232 if (0 <= mode && mode < ARRAY_SIZE(names))
237 EXPORT_SYMBOL(cl_lock_mode_name);
240 * Prints human readable representation of a lock description.
242 void cl_lock_descr_print(const struct lu_env *env, void *cookie,
243 lu_printer_t printer,
244 const struct cl_lock_descr *descr)
246 const struct lu_fid *fid;
248 fid = lu_object_fid(&descr->cld_obj->co_lu);
249 (*printer)(env, cookie, DDESCR"@"DFID, PDESCR(descr), PFID(fid));
251 EXPORT_SYMBOL(cl_lock_descr_print);
254 * Prints human readable representation of \a lock to the \a f.
256 void cl_lock_print(const struct lu_env *env, void *cookie,
257 lu_printer_t printer, const struct cl_lock *lock)
259 const struct cl_lock_slice *slice;
261 (*printer)(env, cookie, "lock@%p", lock);
262 cl_lock_descr_print(env, cookie, printer, &lock->cll_descr);
263 (*printer)(env, cookie, " {\n");
265 list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
266 (*printer)(env, cookie, " %s@%p: ",
267 slice->cls_obj->co_lu.lo_dev->ld_type->ldt_name,
269 if (slice->cls_ops->clo_print)
270 slice->cls_ops->clo_print(env, cookie, printer, slice);
271 (*printer)(env, cookie, "\n");
273 (*printer)(env, cookie, "} lock@%p\n", lock);
275 EXPORT_SYMBOL(cl_lock_print);