1 /* SPDX-License-Identifier: GPL-2.0-only */ !! 1 /* -*- mode: c; c-basic-offset: 8; -*-
2 /* !! 2 * vim: noexpandtab sw=8 ts=8 sts=0:
>> 3 *
3 * stackglue.h 4 * stackglue.h
4 * 5 *
5 * Glue to the underlying cluster stack. 6 * Glue to the underlying cluster stack.
6 * 7 *
7 * Copyright (C) 2007 Oracle. All rights rese 8 * Copyright (C) 2007 Oracle. All rights reserved.
>> 9 *
>> 10 * This program is free software; you can redistribute it and/or
>> 11 * modify it under the terms of the GNU General Public
>> 12 * License as published by the Free Software Foundation, version 2.
>> 13 *
>> 14 * This program 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 GNU
>> 17 * General Public License for more details.
8 */ 18 */
9 19
10 20
11 #ifndef STACKGLUE_H 21 #ifndef STACKGLUE_H
12 #define STACKGLUE_H 22 #define STACKGLUE_H
13 23
14 #include <linux/types.h> 24 #include <linux/types.h>
15 #include <linux/list.h> 25 #include <linux/list.h>
16 #include <linux/dlmconstants.h> 26 #include <linux/dlmconstants.h>
17 27
18 #include "dlm/dlmapi.h" 28 #include "dlm/dlmapi.h"
19 #include <linux/dlm.h> 29 #include <linux/dlm.h>
20 30
21 /* Needed for plock-related prototypes */ 31 /* Needed for plock-related prototypes */
22 struct file; 32 struct file;
23 struct file_lock; 33 struct file_lock;
24 34
25 /* 35 /*
26 * dlmconstants.h does not have a LOCAL flag. 36 * dlmconstants.h does not have a LOCAL flag. We hope to remove it
27 * some day, but right now we need it. Let's 37 * some day, but right now we need it. Let's fake it. This value is larger
28 * than any flag in dlmconstants.h. 38 * than any flag in dlmconstants.h.
29 */ 39 */
30 #define DLM_LKF_LOCAL 0x00100000 40 #define DLM_LKF_LOCAL 0x00100000
31 41
32 /* 42 /*
33 * This shadows DLM_LOCKSPACE_LEN in fs/dlm/dl 43 * This shadows DLM_LOCKSPACE_LEN in fs/dlm/dlm_internal.h. That probably
34 * wants to be in a public header. 44 * wants to be in a public header.
35 */ 45 */
36 #define GROUP_NAME_MAX 64 46 #define GROUP_NAME_MAX 64
37 47
38 /* This shadows OCFS2_CLUSTER_NAME_LEN */ 48 /* This shadows OCFS2_CLUSTER_NAME_LEN */
39 #define CLUSTER_NAME_MAX 16 49 #define CLUSTER_NAME_MAX 16
40 50
41 51
42 /* 52 /*
43 * ocfs2_protocol_version changes when ocfs2 d 53 * ocfs2_protocol_version changes when ocfs2 does something different in
44 * its inter-node behavior. See dlmglue.c for 54 * its inter-node behavior. See dlmglue.c for more information.
45 */ 55 */
46 struct ocfs2_protocol_version { 56 struct ocfs2_protocol_version {
47 u8 pv_major; 57 u8 pv_major;
48 u8 pv_minor; 58 u8 pv_minor;
49 }; 59 };
50 60
51 /* 61 /*
52 * The dlm_lockstatus struct includes lvb spac 62 * The dlm_lockstatus struct includes lvb space, but the dlm_lksb struct only
53 * has a pointer to separately allocated lvb s 63 * has a pointer to separately allocated lvb space. This struct exists only to
54 * include in the lksb union to make space for 64 * include in the lksb union to make space for a combined dlm_lksb and lvb.
55 */ 65 */
56 struct fsdlm_lksb_plus_lvb { 66 struct fsdlm_lksb_plus_lvb {
57 struct dlm_lksb lksb; 67 struct dlm_lksb lksb;
58 char lvb[DLM_LVB_LEN]; 68 char lvb[DLM_LVB_LEN];
59 }; 69 };
60 70
61 /* 71 /*
62 * A union of all lock status structures. We 72 * A union of all lock status structures. We define it here so that the
63 * size of the union is known. Lock status st 73 * size of the union is known. Lock status structures are embedded in
64 * ocfs2 inodes. 74 * ocfs2 inodes.
65 */ 75 */
66 struct ocfs2_cluster_connection; 76 struct ocfs2_cluster_connection;
67 struct ocfs2_dlm_lksb { 77 struct ocfs2_dlm_lksb {
68 union { 78 union {
69 struct dlm_lockstatus lksb_o2 79 struct dlm_lockstatus lksb_o2dlm;
70 struct dlm_lksb lksb_fsdlm; 80 struct dlm_lksb lksb_fsdlm;
71 struct fsdlm_lksb_plus_lvb pa 81 struct fsdlm_lksb_plus_lvb padding;
72 }; 82 };
73 struct ocfs2_cluster_connection *lksb 83 struct ocfs2_cluster_connection *lksb_conn;
74 }; 84 };
75 85
76 /* 86 /*
77 * The ocfs2_locking_protocol defines the hand 87 * The ocfs2_locking_protocol defines the handlers called on ocfs2's behalf.
78 */ 88 */
79 struct ocfs2_locking_protocol { 89 struct ocfs2_locking_protocol {
80 struct ocfs2_protocol_version lp_max_v 90 struct ocfs2_protocol_version lp_max_version;
81 void (*lp_lock_ast)(struct ocfs2_dlm_l 91 void (*lp_lock_ast)(struct ocfs2_dlm_lksb *lksb);
82 void (*lp_blocking_ast)(struct ocfs2_d 92 void (*lp_blocking_ast)(struct ocfs2_dlm_lksb *lksb, int level);
83 void (*lp_unlock_ast)(struct ocfs2_dlm 93 void (*lp_unlock_ast)(struct ocfs2_dlm_lksb *lksb, int error);
84 }; 94 };
85 95
86 96
87 /* 97 /*
88 * A cluster connection. Mostly opaque to ocf 98 * A cluster connection. Mostly opaque to ocfs2, the connection holds
89 * state for the underlying stack. ocfs2 does 99 * state for the underlying stack. ocfs2 does use cc_version to determine
90 * locking compatibility. 100 * locking compatibility.
91 */ 101 */
92 struct ocfs2_cluster_connection { 102 struct ocfs2_cluster_connection {
93 char cc_name[GROUP_NAME_MAX + 1]; 103 char cc_name[GROUP_NAME_MAX + 1];
94 int cc_namelen; 104 int cc_namelen;
95 char cc_cluster_name[CLUSTER_NAME_MAX 105 char cc_cluster_name[CLUSTER_NAME_MAX + 1];
96 int cc_cluster_name_len; 106 int cc_cluster_name_len;
97 struct ocfs2_protocol_version cc_versi 107 struct ocfs2_protocol_version cc_version;
98 struct ocfs2_locking_protocol *cc_prot 108 struct ocfs2_locking_protocol *cc_proto;
99 void (*cc_recovery_handler)(int node_n 109 void (*cc_recovery_handler)(int node_num, void *recovery_data);
100 void *cc_recovery_data; 110 void *cc_recovery_data;
101 void *cc_lockspace; 111 void *cc_lockspace;
102 void *cc_private; 112 void *cc_private;
103 }; 113 };
104 114
105 /* 115 /*
106 * Each cluster stack implements the stack ope 116 * Each cluster stack implements the stack operations structure. Not used
107 * in the ocfs2 code, the stackglue code trans 117 * in the ocfs2 code, the stackglue code translates generic cluster calls
108 * into stack operations. 118 * into stack operations.
109 */ 119 */
110 struct ocfs2_stack_operations { 120 struct ocfs2_stack_operations {
111 /* 121 /*
112 * The fs code calls ocfs2_cluster_con 122 * The fs code calls ocfs2_cluster_connect() to attach a new
113 * filesystem to the cluster stack. T 123 * filesystem to the cluster stack. The ->connect() op is passed
114 * an ocfs2_cluster_connection with th 124 * an ocfs2_cluster_connection with the name and recovery field
115 * filled in. 125 * filled in.
116 * 126 *
117 * The stack must set up any notificat 127 * The stack must set up any notification mechanisms and create
118 * the filesystem lockspace in the DLM 128 * the filesystem lockspace in the DLM. The lockspace should be
119 * stored on cc_lockspace. Any other 129 * stored on cc_lockspace. Any other information can be stored on
120 * cc_private. 130 * cc_private.
121 * 131 *
122 * ->connect() must not return until i 132 * ->connect() must not return until it is guaranteed that
123 * 133 *
124 * - Node down notifications for the 134 * - Node down notifications for the filesystem will be received
125 * and passed to conn->cc_recovery_ 135 * and passed to conn->cc_recovery_handler().
126 * - Locking requests for the filesys 136 * - Locking requests for the filesystem will be processed.
127 */ 137 */
128 int (*connect)(struct ocfs2_cluster_co 138 int (*connect)(struct ocfs2_cluster_connection *conn);
129 139
130 /* 140 /*
131 * The fs code calls ocfs2_cluster_dis 141 * The fs code calls ocfs2_cluster_disconnect() when a filesystem
132 * no longer needs cluster services. 142 * no longer needs cluster services. All DLM locks have been
133 * dropped, and recovery notification 143 * dropped, and recovery notification is being ignored by the
134 * fs code. The stack must disengage 144 * fs code. The stack must disengage from the DLM and discontinue
135 * recovery notification. 145 * recovery notification.
136 * 146 *
137 * Once ->disconnect() has returned, t 147 * Once ->disconnect() has returned, the connection structure will
138 * be freed. Thus, a stack must not r 148 * be freed. Thus, a stack must not return from ->disconnect()
139 * until it will no longer reference t 149 * until it will no longer reference the conn pointer.
140 * 150 *
141 * Once this call returns, the stack g 151 * Once this call returns, the stack glue will be dropping this
142 * connection's reference on the modul 152 * connection's reference on the module.
143 */ 153 */
144 int (*disconnect)(struct ocfs2_cluster 154 int (*disconnect)(struct ocfs2_cluster_connection *conn);
145 155
146 /* 156 /*
147 * ->this_node() returns the cluster's 157 * ->this_node() returns the cluster's unique identifier for the
148 * local node. 158 * local node.
149 */ 159 */
150 int (*this_node)(struct ocfs2_cluster_ 160 int (*this_node)(struct ocfs2_cluster_connection *conn,
151 unsigned int *node); 161 unsigned int *node);
152 162
153 /* 163 /*
154 * Call the underlying dlm lock functi 164 * Call the underlying dlm lock function. The ->dlm_lock()
155 * callback should convert the flags a 165 * callback should convert the flags and mode as appropriate.
156 * 166 *
157 * ast and bast functions are not part 167 * ast and bast functions are not part of the call because the
158 * stack will likely want to wrap ast 168 * stack will likely want to wrap ast and bast calls before passing
159 * them to stack->sp_proto. There is 169 * them to stack->sp_proto. There is no astarg. The lksb will
160 * be passed back to the ast and bast 170 * be passed back to the ast and bast functions. The caller can
161 * use this to find their object. 171 * use this to find their object.
162 */ 172 */
163 int (*dlm_lock)(struct ocfs2_cluster_c 173 int (*dlm_lock)(struct ocfs2_cluster_connection *conn,
164 int mode, 174 int mode,
165 struct ocfs2_dlm_lksb 175 struct ocfs2_dlm_lksb *lksb,
166 u32 flags, 176 u32 flags,
167 void *name, 177 void *name,
168 unsigned int namelen); 178 unsigned int namelen);
169 179
170 /* 180 /*
171 * Call the underlying dlm unlock func 181 * Call the underlying dlm unlock function. The ->dlm_unlock()
172 * function should convert the flags a 182 * function should convert the flags as appropriate.
173 * 183 *
174 * The unlock ast is not passed, as th 184 * The unlock ast is not passed, as the stack will want to wrap
175 * it before calling stack->sp_proto-> 185 * it before calling stack->sp_proto->lp_unlock_ast(). There is
176 * no astarg. The lksb will be passed 186 * no astarg. The lksb will be passed back to the unlock ast
177 * function. The caller can use this 187 * function. The caller can use this to find their object.
178 */ 188 */
179 int (*dlm_unlock)(struct ocfs2_cluster 189 int (*dlm_unlock)(struct ocfs2_cluster_connection *conn,
180 struct ocfs2_dlm_lks 190 struct ocfs2_dlm_lksb *lksb,
181 u32 flags); 191 u32 flags);
182 192
183 /* 193 /*
184 * Return the status of the current lo 194 * Return the status of the current lock status block. The fs
185 * code should never dereference the u 195 * code should never dereference the union. The ->lock_status()
186 * callback pulls out the stack-specif 196 * callback pulls out the stack-specific lksb, converts the status
187 * to a proper errno, and returns it. 197 * to a proper errno, and returns it.
188 */ 198 */
189 int (*lock_status)(struct ocfs2_dlm_lk 199 int (*lock_status)(struct ocfs2_dlm_lksb *lksb);
190 200
191 /* 201 /*
192 * Return non-zero if the LVB is valid 202 * Return non-zero if the LVB is valid.
193 */ 203 */
194 int (*lvb_valid)(struct ocfs2_dlm_lksb 204 int (*lvb_valid)(struct ocfs2_dlm_lksb *lksb);
195 205
196 /* 206 /*
197 * Pull the lvb pointer off of the sta 207 * Pull the lvb pointer off of the stack-specific lksb.
198 */ 208 */
199 void *(*lock_lvb)(struct ocfs2_dlm_lks 209 void *(*lock_lvb)(struct ocfs2_dlm_lksb *lksb);
200 210
201 /* 211 /*
202 * Cluster-aware posix locks 212 * Cluster-aware posix locks
203 * 213 *
204 * This is NULL for stacks which do no 214 * This is NULL for stacks which do not support posix locks.
205 */ 215 */
206 int (*plock)(struct ocfs2_cluster_conn 216 int (*plock)(struct ocfs2_cluster_connection *conn,
207 u64 ino, 217 u64 ino,
208 struct file *file, 218 struct file *file,
209 int cmd, 219 int cmd,
210 struct file_lock *fl); 220 struct file_lock *fl);
211 221
212 /* 222 /*
213 * This is an optoinal debugging hook. 223 * This is an optoinal debugging hook. If provided, the
214 * stack can dump debugging informatio 224 * stack can dump debugging information about this lock.
215 */ 225 */
216 void (*dump_lksb)(struct ocfs2_dlm_lks 226 void (*dump_lksb)(struct ocfs2_dlm_lksb *lksb);
217 }; 227 };
218 228
219 /* 229 /*
220 * Each stack plugin must describe itself by r 230 * Each stack plugin must describe itself by registering a
221 * ocfs2_stack_plugin structure. This is only 231 * ocfs2_stack_plugin structure. This is only seen by stackglue and the
222 * stack driver. 232 * stack driver.
223 */ 233 */
224 struct ocfs2_stack_plugin { 234 struct ocfs2_stack_plugin {
225 char *sp_name; 235 char *sp_name;
226 const struct ocfs2_stack_operations *s !! 236 struct ocfs2_stack_operations *sp_ops;
227 struct module *sp_owner; 237 struct module *sp_owner;
228 238
229 /* These are managed by the stackglue 239 /* These are managed by the stackglue code. */
230 struct list_head sp_list; 240 struct list_head sp_list;
231 unsigned int sp_count; 241 unsigned int sp_count;
232 struct ocfs2_protocol_version sp_max_p 242 struct ocfs2_protocol_version sp_max_proto;
233 }; 243 };
234 244
235 245
236 /* Used by the filesystem */ 246 /* Used by the filesystem */
237 int ocfs2_cluster_connect(const char *stack_na 247 int ocfs2_cluster_connect(const char *stack_name,
238 const char *cluster_ 248 const char *cluster_name,
239 int cluster_name_len 249 int cluster_name_len,
240 const char *group, 250 const char *group,
241 int grouplen, 251 int grouplen,
242 struct ocfs2_locking 252 struct ocfs2_locking_protocol *lproto,
243 void (*recovery_hand 253 void (*recovery_handler)(int node_num,
244 254 void *recovery_data),
245 void *recovery_data, 255 void *recovery_data,
246 struct ocfs2_cluster 256 struct ocfs2_cluster_connection **conn);
247 /* 257 /*
248 * Used by callers that don't store their stac 258 * Used by callers that don't store their stack name. They must ensure
249 * all nodes have the same stack. 259 * all nodes have the same stack.
250 */ 260 */
251 int ocfs2_cluster_connect_agnostic(const char 261 int ocfs2_cluster_connect_agnostic(const char *group,
252 int grouple 262 int grouplen,
253 struct ocfs 263 struct ocfs2_locking_protocol *lproto,
254 void (*reco 264 void (*recovery_handler)(int node_num,
255 265 void *recovery_data),
256 void *recov 266 void *recovery_data,
257 struct ocfs 267 struct ocfs2_cluster_connection **conn);
258 int ocfs2_cluster_disconnect(struct ocfs2_clus 268 int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn,
259 int hangup_pendin 269 int hangup_pending);
260 void ocfs2_cluster_hangup(const char *group, i 270 void ocfs2_cluster_hangup(const char *group, int grouplen);
261 int ocfs2_cluster_this_node(struct ocfs2_clust 271 int ocfs2_cluster_this_node(struct ocfs2_cluster_connection *conn,
262 unsigned int *node 272 unsigned int *node);
263 273
264 struct ocfs2_lock_res; 274 struct ocfs2_lock_res;
265 int ocfs2_dlm_lock(struct ocfs2_cluster_connec 275 int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
266 int mode, 276 int mode,
267 struct ocfs2_dlm_lksb *lksb 277 struct ocfs2_dlm_lksb *lksb,
268 u32 flags, 278 u32 flags,
269 void *name, 279 void *name,
270 unsigned int namelen); 280 unsigned int namelen);
271 int ocfs2_dlm_unlock(struct ocfs2_cluster_conn 281 int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
272 struct ocfs2_dlm_lksb *lk 282 struct ocfs2_dlm_lksb *lksb,
273 u32 flags); 283 u32 flags);
274 284
275 int ocfs2_dlm_lock_status(struct ocfs2_dlm_lks 285 int ocfs2_dlm_lock_status(struct ocfs2_dlm_lksb *lksb);
276 int ocfs2_dlm_lvb_valid(struct ocfs2_dlm_lksb 286 int ocfs2_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb);
277 void *ocfs2_dlm_lvb(struct ocfs2_dlm_lksb *lks 287 void *ocfs2_dlm_lvb(struct ocfs2_dlm_lksb *lksb);
278 void ocfs2_dlm_dump_lksb(struct ocfs2_dlm_lksb 288 void ocfs2_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb);
279 289
280 int ocfs2_stack_supports_plocks(void); 290 int ocfs2_stack_supports_plocks(void);
281 int ocfs2_plock(struct ocfs2_cluster_connectio 291 int ocfs2_plock(struct ocfs2_cluster_connection *conn, u64 ino,
282 struct file *file, int cmd, st 292 struct file *file, int cmd, struct file_lock *fl);
283 293
284 void ocfs2_stack_glue_set_max_proto_version(st 294 void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_proto);
285 295
286 296
287 /* Used by stack plugins */ 297 /* Used by stack plugins */
288 int ocfs2_stack_glue_register(struct ocfs2_sta 298 int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin);
289 void ocfs2_stack_glue_unregister(struct ocfs2_ 299 void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin);
290 <<
291 extern struct kset *ocfs2_kset; <<
292 300
293 #endif /* STACKGLUE_H */ 301 #endif /* STACKGLUE_H */
294 302
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