1 /*
2 * GPL HEADER START
3 *
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
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.
9 *
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).
15 *
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.sun.com/software/products/lustre/docs/GPLv2.pdf
19 *
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
22 * have any questions.
23 *
24 * GPL HEADER END
25 */
26 /*
27 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
29 *
30 * Copyright (c) 2011, 2012, Intel Corporation.
31 */
32 /*
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
35 *
36 * lustre/ptlrpc/sec_gc.c
37 *
38 * Author: Eric Mei <ericm@clusterfs.com>
39 */
40
41 #define DEBUG_SUBSYSTEM S_SEC
42
43 #include "../../include/linux/libcfs/libcfs.h"
44
45 #include "../include/obd_support.h"
46 #include "../include/obd_class.h"
47 #include "../include/lustre_net.h"
48 #include "../include/lustre_sec.h"
49
50 #include "ptlrpc_internal.h"
51
52 #define SEC_GC_INTERVAL (30 * 60)
53
54
55 static struct mutex sec_gc_mutex;
56 static LIST_HEAD(sec_gc_list);
57 static spinlock_t sec_gc_list_lock;
58
59 static LIST_HEAD(sec_gc_ctx_list);
60 static spinlock_t sec_gc_ctx_list_lock;
61
62 static struct ptlrpc_thread sec_gc_thread;
63 static atomic_t sec_gc_wait_del = ATOMIC_INIT(0);
64
65
sptlrpc_gc_add_sec(struct ptlrpc_sec * sec)66 void sptlrpc_gc_add_sec(struct ptlrpc_sec *sec)
67 {
68 LASSERT(sec->ps_policy->sp_cops->gc_ctx);
69 LASSERT(sec->ps_gc_interval > 0);
70 LASSERT(list_empty(&sec->ps_gc_list));
71
72 sec->ps_gc_next = get_seconds() + sec->ps_gc_interval;
73
74 spin_lock(&sec_gc_list_lock);
75 list_add_tail(&sec_gc_list, &sec->ps_gc_list);
76 spin_unlock(&sec_gc_list_lock);
77
78 CDEBUG(D_SEC, "added sec %p(%s)\n", sec, sec->ps_policy->sp_name);
79 }
80 EXPORT_SYMBOL(sptlrpc_gc_add_sec);
81
sptlrpc_gc_del_sec(struct ptlrpc_sec * sec)82 void sptlrpc_gc_del_sec(struct ptlrpc_sec *sec)
83 {
84 if (list_empty(&sec->ps_gc_list))
85 return;
86
87 might_sleep();
88
89 /* signal before list_del to make iteration in gc thread safe */
90 atomic_inc(&sec_gc_wait_del);
91
92 spin_lock(&sec_gc_list_lock);
93 list_del_init(&sec->ps_gc_list);
94 spin_unlock(&sec_gc_list_lock);
95
96 /* barrier */
97 mutex_lock(&sec_gc_mutex);
98 mutex_unlock(&sec_gc_mutex);
99
100 atomic_dec(&sec_gc_wait_del);
101
102 CDEBUG(D_SEC, "del sec %p(%s)\n", sec, sec->ps_policy->sp_name);
103 }
104 EXPORT_SYMBOL(sptlrpc_gc_del_sec);
105
sptlrpc_gc_add_ctx(struct ptlrpc_cli_ctx * ctx)106 void sptlrpc_gc_add_ctx(struct ptlrpc_cli_ctx *ctx)
107 {
108 LASSERT(list_empty(&ctx->cc_gc_chain));
109
110 CDEBUG(D_SEC, "hand over ctx %p(%u->%s)\n",
111 ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec));
112 spin_lock(&sec_gc_ctx_list_lock);
113 list_add(&ctx->cc_gc_chain, &sec_gc_ctx_list);
114 spin_unlock(&sec_gc_ctx_list_lock);
115
116 thread_add_flags(&sec_gc_thread, SVC_SIGNAL);
117 wake_up(&sec_gc_thread.t_ctl_waitq);
118 }
119 EXPORT_SYMBOL(sptlrpc_gc_add_ctx);
120
sec_process_ctx_list(void)121 static void sec_process_ctx_list(void)
122 {
123 struct ptlrpc_cli_ctx *ctx;
124
125 spin_lock(&sec_gc_ctx_list_lock);
126
127 while (!list_empty(&sec_gc_ctx_list)) {
128 ctx = list_entry(sec_gc_ctx_list.next,
129 struct ptlrpc_cli_ctx, cc_gc_chain);
130 list_del_init(&ctx->cc_gc_chain);
131 spin_unlock(&sec_gc_ctx_list_lock);
132
133 LASSERT(ctx->cc_sec);
134 LASSERT(atomic_read(&ctx->cc_refcount) == 1);
135 CDEBUG(D_SEC, "gc pick up ctx %p(%u->%s)\n",
136 ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec));
137 sptlrpc_cli_ctx_put(ctx, 1);
138
139 spin_lock(&sec_gc_ctx_list_lock);
140 }
141
142 spin_unlock(&sec_gc_ctx_list_lock);
143 }
144
sec_do_gc(struct ptlrpc_sec * sec)145 static void sec_do_gc(struct ptlrpc_sec *sec)
146 {
147 LASSERT(sec->ps_policy->sp_cops->gc_ctx);
148
149 if (unlikely(sec->ps_gc_next == 0)) {
150 CDEBUG(D_SEC, "sec %p(%s) has 0 gc time\n",
151 sec, sec->ps_policy->sp_name);
152 return;
153 }
154
155 CDEBUG(D_SEC, "check on sec %p(%s)\n", sec, sec->ps_policy->sp_name);
156
157 if (cfs_time_after(sec->ps_gc_next, get_seconds()))
158 return;
159
160 sec->ps_policy->sp_cops->gc_ctx(sec);
161 sec->ps_gc_next = get_seconds() + sec->ps_gc_interval;
162 }
163
sec_gc_main(void * arg)164 static int sec_gc_main(void *arg)
165 {
166 struct ptlrpc_thread *thread = (struct ptlrpc_thread *) arg;
167 struct l_wait_info lwi;
168
169 unshare_fs_struct();
170
171 /* Record that the thread is running */
172 thread_set_flags(thread, SVC_RUNNING);
173 wake_up(&thread->t_ctl_waitq);
174
175 while (1) {
176 struct ptlrpc_sec *sec;
177
178 thread_clear_flags(thread, SVC_SIGNAL);
179 sec_process_ctx_list();
180 again:
181 /* go through sec list do gc.
182 * FIXME here we iterate through the whole list each time which
183 * is not optimal. we perhaps want to use balanced binary tree
184 * to trace each sec as order of expiry time.
185 * another issue here is we wakeup as fixed interval instead of
186 * according to each sec's expiry time */
187 mutex_lock(&sec_gc_mutex);
188 list_for_each_entry(sec, &sec_gc_list, ps_gc_list) {
189 /* if someone is waiting to be deleted, let it
190 * proceed as soon as possible. */
191 if (atomic_read(&sec_gc_wait_del)) {
192 CDEBUG(D_SEC, "deletion pending, start over\n");
193 mutex_unlock(&sec_gc_mutex);
194 goto again;
195 }
196
197 sec_do_gc(sec);
198 }
199 mutex_unlock(&sec_gc_mutex);
200
201 /* check ctx list again before sleep */
202 sec_process_ctx_list();
203
204 lwi = LWI_TIMEOUT(SEC_GC_INTERVAL * HZ, NULL, NULL);
205 l_wait_event(thread->t_ctl_waitq,
206 thread_is_stopping(thread) ||
207 thread_is_signal(thread),
208 &lwi);
209
210 if (thread_test_and_clear_flags(thread, SVC_STOPPING))
211 break;
212 }
213
214 thread_set_flags(thread, SVC_STOPPED);
215 wake_up(&thread->t_ctl_waitq);
216 return 0;
217 }
218
sptlrpc_gc_init(void)219 int sptlrpc_gc_init(void)
220 {
221 struct l_wait_info lwi = { 0 };
222 struct task_struct *task;
223
224 mutex_init(&sec_gc_mutex);
225 spin_lock_init(&sec_gc_list_lock);
226 spin_lock_init(&sec_gc_ctx_list_lock);
227
228 /* initialize thread control */
229 memset(&sec_gc_thread, 0, sizeof(sec_gc_thread));
230 init_waitqueue_head(&sec_gc_thread.t_ctl_waitq);
231
232 task = kthread_run(sec_gc_main, &sec_gc_thread, "sptlrpc_gc");
233 if (IS_ERR(task)) {
234 CERROR("can't start gc thread: %ld\n", PTR_ERR(task));
235 return PTR_ERR(task);
236 }
237
238 l_wait_event(sec_gc_thread.t_ctl_waitq,
239 thread_is_running(&sec_gc_thread), &lwi);
240 return 0;
241 }
242
sptlrpc_gc_fini(void)243 void sptlrpc_gc_fini(void)
244 {
245 struct l_wait_info lwi = { 0 };
246
247 thread_set_flags(&sec_gc_thread, SVC_STOPPING);
248 wake_up(&sec_gc_thread.t_ctl_waitq);
249
250 l_wait_event(sec_gc_thread.t_ctl_waitq,
251 thread_is_stopped(&sec_gc_thread), &lwi);
252 }
253