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[fs/lustre-release.git] / lustre / ldlm / ldlm_internal.h
1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  * GPL HEADER START
5  *
6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 only,
10  * as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License version 2 for more details (a copy is included
16  * in the LICENSE file that accompanied this code).
17  *
18  * You should have received a copy of the GNU General Public License
19  * version 2 along with this program; If not, see
20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
21  *
22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23  * CA 95054 USA or visit www.sun.com if you need additional information or
24  * have any questions.
25  *
26  * GPL HEADER END
27  */
28 /*
29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
30  * Use is subject to license terms.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  */
36
37 #define MAX_STRING_SIZE 128
38
39 extern atomic_t ldlm_srv_namespace_nr;
40 extern atomic_t ldlm_cli_namespace_nr;
41 extern struct semaphore ldlm_srv_namespace_lock;
42 extern struct list_head ldlm_srv_namespace_list;
43 extern struct semaphore ldlm_cli_namespace_lock;
44 extern struct list_head ldlm_cli_namespace_list;
45
46 static inline atomic_t *ldlm_namespace_nr(ldlm_side_t client)
47 {
48         return client == LDLM_NAMESPACE_SERVER ?
49                 &ldlm_srv_namespace_nr : &ldlm_cli_namespace_nr;
50 }
51
52 static inline struct list_head *ldlm_namespace_list(ldlm_side_t client)
53 {
54         return client == LDLM_NAMESPACE_SERVER ?
55                 &ldlm_srv_namespace_list : &ldlm_cli_namespace_list;
56 }
57
58 static inline struct semaphore *ldlm_namespace_lock(ldlm_side_t client)
59 {
60         return client == LDLM_NAMESPACE_SERVER ?
61                 &ldlm_srv_namespace_lock : &ldlm_cli_namespace_lock;
62 }
63
64 /* ldlm_request.c */
65 typedef enum {
66         LDLM_ASYNC,
67         LDLM_SYNC,
68 } ldlm_sync_t;
69
70 /* Cancel lru flag, it indicates we cancel aged locks. */
71 enum {
72         LDLM_CANCEL_AGED   = 1 << 0, /* Cancel aged locks (non lru resize). */
73         LDLM_CANCEL_PASSED = 1 << 1, /* Cancel passed number of locks. */
74         LDLM_CANCEL_SHRINK = 1 << 2, /* Cancel locks from shrinker. */
75         LDLM_CANCEL_LRUR   = 1 << 3  /* Cancel locks from lru resize. */
76 };
77
78 int ldlm_cancel_lru(struct ldlm_namespace *ns, int nr, ldlm_sync_t sync,
79                     int flags);
80 int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
81                           int count, int max, int cancel_flags, int flags);
82 extern int ldlm_enqueue_min;
83 int ldlm_get_enq_timeout(struct ldlm_lock *lock);
84
85 /* ldlm_resource.c */
86 int ldlm_resource_putref_locked(struct ldlm_resource *res);
87 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
88                                      struct ldlm_lock *new);
89 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
90                                struct obd_import *imp, int force);
91 void ldlm_namespace_free_post(struct ldlm_namespace *ns);
92
93 /* ldlm_lock.c */
94
95 /* Number of blocking/completion callbacks that will be sent in
96  * parallel (see bug 11301). */
97 #define PARALLEL_AST_LIMIT      200
98
99 struct ldlm_cb_set_arg {
100         struct ptlrpc_request_set *set;
101         atomic_t restart;
102         __u32 type; /* LDLM_BL_CALLBACK or LDLM_CP_CALLBACK */
103 };
104
105 void ldlm_grant_lock(struct ldlm_lock *lock, struct list_head *work_list);
106 struct ldlm_lock *
107 ldlm_lock_create(struct ldlm_namespace *ns, struct ldlm_res_id,
108                  ldlm_type_t type, ldlm_mode_t, ldlm_blocking_callback,
109                  ldlm_completion_callback, ldlm_glimpse_callback, void *data,
110                  __u32 lvb_len);
111 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *, struct ldlm_lock **,
112                                void *cookie, int *flags);
113 void ldlm_lock_addref_internal(struct ldlm_lock *, __u32 mode);
114 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *, __u32 mode);
115 void ldlm_lock_decref_internal(struct ldlm_lock *, __u32 mode);
116 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *, __u32 mode);
117 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
118                                 struct list_head *work_list);
119 int ldlm_reprocess_queue(struct ldlm_resource *res, struct list_head *queue,
120                          struct list_head *work_list);
121 int ldlm_run_bl_ast_work(struct list_head *rpc_list);
122 int ldlm_run_cp_ast_work(struct list_head *rpc_list);
123 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock);
124 int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock);
125 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock);
126 void ldlm_lock_add_to_lru(struct ldlm_lock *lock);
127 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock);
128 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock);
129
130 /* ldlm_lockd.c */
131 int ldlm_bl_to_thread_lock(struct ldlm_namespace *ns, struct ldlm_lock_desc *ld,
132                            struct ldlm_lock *lock);
133 int ldlm_bl_to_thread_list(struct ldlm_namespace *ns, struct ldlm_lock_desc *ld,
134                            struct list_head *cancels, int count);
135
136 void ldlm_handle_bl_callback(struct ldlm_namespace *ns,
137                              struct ldlm_lock_desc *ld, struct ldlm_lock *lock);
138
139 /* ldlm_plain.c */
140 int ldlm_process_plain_lock(struct ldlm_lock *lock, int *flags, int first_enq,
141                             ldlm_error_t *err, struct list_head *work_list);
142
143 /* ldlm_extent.c */
144 int ldlm_process_extent_lock(struct ldlm_lock *lock, int *flags, int first_enq,
145                              ldlm_error_t *err, struct list_head *work_list);
146 void ldlm_extent_add_lock(struct ldlm_resource *res, struct ldlm_lock *lock);
147 void ldlm_extent_unlink_lock(struct ldlm_lock *lock);
148
149 /* ldlm_flock.c */
150 int ldlm_process_flock_lock(struct ldlm_lock *req, int *flags, int first_enq,
151                             ldlm_error_t *err, struct list_head *work_list);
152
153 /* ldlm_inodebits.c */
154 int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags,
155                                 int first_enq, ldlm_error_t *err,
156                                 struct list_head *work_list);
157
158 /* l_lock.c */
159 void l_check_ns_lock(struct ldlm_namespace *ns);
160 void l_check_no_ns_lock(struct ldlm_namespace *ns);
161
162 extern cfs_proc_dir_entry_t *ldlm_svc_proc_dir;
163 extern cfs_proc_dir_entry_t *ldlm_type_proc_dir;
164
165 struct ldlm_state {
166         struct ptlrpc_service *ldlm_cb_service;
167         struct ptlrpc_service *ldlm_cancel_service;
168         struct ptlrpc_client *ldlm_client;
169         struct ptlrpc_connection *ldlm_server_conn;
170         struct ldlm_bl_pool *ldlm_bl_pool;
171 };
172
173 /* interval tree, for LDLM_EXTENT. */
174 extern cfs_mem_cache_t *ldlm_interval_slab; /* slab cache for ldlm_interval */
175 extern void ldlm_interval_attach(struct ldlm_interval *n, struct ldlm_lock *l);
176 extern struct ldlm_interval *ldlm_interval_detach(struct ldlm_lock *l);
177 extern struct ldlm_interval *ldlm_interval_alloc(struct ldlm_lock *lock);
178 extern void ldlm_interval_free(struct ldlm_interval *node);
179 /* this function must be called with res lock held */
180 static inline struct ldlm_extent *
181 ldlm_interval_extent(struct ldlm_interval *node)
182 {
183         struct ldlm_lock *lock;
184         LASSERT(!list_empty(&node->li_group));
185
186         lock = list_entry(node->li_group.next, struct ldlm_lock, l_sl_policy);
187         return &lock->l_policy_data.l_extent;
188 }
189
190 int ldlm_init(void);
191 void ldlm_exit(void);
192
193 enum ldlm_policy_res {
194         LDLM_POLICY_CANCEL_LOCK,
195         LDLM_POLICY_KEEP_LOCK
196 };
197
198 typedef enum ldlm_policy_res ldlm_policy_res_t;
199
200 #define LDLM_POOL_PROC_READER(var, type)                                    \
201         static int lprocfs_rd_##var(char *page, char **start, off_t off,    \
202                                     int count, int *eof, void *data)        \
203         {                                                                   \
204                 struct ldlm_pool *pl = data;                                \
205                 type tmp;                                                   \
206                                                                             \
207                 spin_lock(&pl->pl_lock);                                    \
208                 tmp = pl->pl_##var;                                         \
209                 spin_unlock(&pl->pl_lock);                                  \
210                                                                             \
211                 return lprocfs_rd_uint(page, start, off, count, eof, &tmp); \
212         }                                                                   \
213         struct __##var##__dummy_read {;} /* semicolon catcher */
214
215 #define LDLM_POOL_PROC_WRITER(var, type)                                    \
216         int lprocfs_wr_##var(struct file *file, const char *buffer,         \
217                              unsigned long count, void *data)               \
218         {                                                                   \
219                 struct ldlm_pool *pl = data;                                \
220                 type tmp;                                                   \
221                 int rc;                                                     \
222                                                                             \
223                 rc = lprocfs_wr_uint(file, buffer, count, &tmp);            \
224                 if (rc) {                                                   \
225                         CERROR("Can't parse user input, rc = %d\n", rc);    \
226                         return rc;                                          \
227                 }                                                           \
228                                                                             \
229                 spin_lock(&pl->pl_lock);                                    \
230                 pl->pl_##var = tmp;                                         \
231                 spin_unlock(&pl->pl_lock);                                  \
232                                                                             \
233                 return rc;                                                  \
234         }                                                                   \
235         struct __##var##__dummy_write {;} /* semicolon catcher */
236
237 static inline int is_granted_or_cancelled(struct ldlm_lock *lock)
238 {
239         int ret = 0;
240
241         lock_res_and_lock(lock);
242         if (((lock->l_req_mode == lock->l_granted_mode) &&
243              !(lock->l_flags & LDLM_FL_CP_REQD)) ||
244             (lock->l_flags & LDLM_FL_FAILED))
245                 ret = 1;
246         unlock_res_and_lock(lock);
247
248         return ret;
249 }