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