Commit | Line | Data |
---|---|---|
50acfb2b | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
fa60ce2c | 2 | /* |
24ef1815 JB |
3 | * stackglue.h |
4 | * | |
5 | * Glue to the underlying cluster stack. | |
6 | * | |
7 | * Copyright (C) 2007 Oracle. All rights reserved. | |
24ef1815 JB |
8 | */ |
9 | ||
10 | ||
11 | #ifndef STACKGLUE_H | |
12 | #define STACKGLUE_H | |
13 | ||
bd3e7610 JB |
14 | #include <linux/types.h> |
15 | #include <linux/list.h> | |
16 | #include <linux/dlmconstants.h> | |
17 | ||
e3dad42b | 18 | #include "dlm/dlmapi.h" |
cf4d8d75 | 19 | #include <linux/dlm.h> |
e3dad42b | 20 | |
53da4939 MF |
21 | /* Needed for plock-related prototypes */ |
22 | struct file; | |
23 | struct file_lock; | |
24 | ||
bd3e7610 JB |
25 | /* |
26 | * dlmconstants.h does not have a LOCAL flag. We hope to remove it | |
27 | * some day, but right now we need it. Let's fake it. This value is larger | |
28 | * than any flag in dlmconstants.h. | |
29 | */ | |
30 | #define DLM_LKF_LOCAL 0x00100000 | |
31 | ||
4670c46d JB |
32 | /* |
33 | * This shadows DLM_LOCKSPACE_LEN in fs/dlm/dlm_internal.h. That probably | |
34 | * wants to be in a public header. | |
35 | */ | |
36 | #define GROUP_NAME_MAX 64 | |
37 | ||
c74a3bdd GR |
38 | /* This shadows OCFS2_CLUSTER_NAME_LEN */ |
39 | #define CLUSTER_NAME_MAX 16 | |
40 | ||
4670c46d | 41 | |
e3dad42b JB |
42 | /* |
43 | * ocfs2_protocol_version changes when ocfs2 does something different in | |
44 | * its inter-node behavior. See dlmglue.c for more information. | |
45 | */ | |
4670c46d JB |
46 | struct ocfs2_protocol_version { |
47 | u8 pv_major; | |
48 | u8 pv_minor; | |
49 | }; | |
50 | ||
cf4d8d75 DT |
51 | /* |
52 | * The dlm_lockstatus struct includes lvb space, but the dlm_lksb struct only | |
53 | * has a pointer to separately allocated lvb space. This struct exists only to | |
54 | * include in the lksb union to make space for a combined dlm_lksb and lvb. | |
55 | */ | |
56 | struct fsdlm_lksb_plus_lvb { | |
57 | struct dlm_lksb lksb; | |
58 | char lvb[DLM_LVB_LEN]; | |
59 | }; | |
60 | ||
e3dad42b JB |
61 | /* |
62 | * A union of all lock status structures. We define it here so that the | |
63 | * size of the union is known. Lock status structures are embedded in | |
64 | * ocfs2 inodes. | |
65 | */ | |
c0e41338 JB |
66 | struct ocfs2_cluster_connection; |
67 | struct ocfs2_dlm_lksb { | |
68 | union { | |
69 | struct dlm_lockstatus lksb_o2dlm; | |
70 | struct dlm_lksb lksb_fsdlm; | |
71 | struct fsdlm_lksb_plus_lvb padding; | |
72 | }; | |
73 | struct ocfs2_cluster_connection *lksb_conn; | |
8f2c9c1b JB |
74 | }; |
75 | ||
a796d286 JB |
76 | /* |
77 | * The ocfs2_locking_protocol defines the handlers called on ocfs2's behalf. | |
78 | */ | |
79 | struct ocfs2_locking_protocol { | |
80 | struct ocfs2_protocol_version lp_max_version; | |
c0e41338 JB |
81 | void (*lp_lock_ast)(struct ocfs2_dlm_lksb *lksb); |
82 | void (*lp_blocking_ast)(struct ocfs2_dlm_lksb *lksb, int level); | |
83 | void (*lp_unlock_ast)(struct ocfs2_dlm_lksb *lksb, int error); | |
a796d286 JB |
84 | }; |
85 | ||
86 | ||
e3dad42b JB |
87 | /* |
88 | * A cluster connection. Mostly opaque to ocfs2, the connection holds | |
89 | * state for the underlying stack. ocfs2 does use cc_version to determine | |
90 | * locking compatibility. | |
91 | */ | |
4670c46d | 92 | struct ocfs2_cluster_connection { |
c74a3bdd | 93 | char cc_name[GROUP_NAME_MAX + 1]; |
4670c46d | 94 | int cc_namelen; |
c74a3bdd GR |
95 | char cc_cluster_name[CLUSTER_NAME_MAX + 1]; |
96 | int cc_cluster_name_len; | |
4670c46d | 97 | struct ocfs2_protocol_version cc_version; |
110946c8 | 98 | struct ocfs2_locking_protocol *cc_proto; |
4670c46d JB |
99 | void (*cc_recovery_handler)(int node_num, void *recovery_data); |
100 | void *cc_recovery_data; | |
101 | void *cc_lockspace; | |
102 | void *cc_private; | |
103 | }; | |
104 | ||
e3dad42b JB |
105 | /* |
106 | * Each cluster stack implements the stack operations structure. Not used | |
107 | * in the ocfs2 code, the stackglue code translates generic cluster calls | |
108 | * into stack operations. | |
109 | */ | |
110 | struct ocfs2_stack_operations { | |
111 | /* | |
112 | * The fs code calls ocfs2_cluster_connect() to attach a new | |
113 | * filesystem to the cluster stack. The ->connect() op is passed | |
114 | * an ocfs2_cluster_connection with the name and recovery field | |
115 | * filled in. | |
116 | * | |
117 | * The stack must set up any notification mechanisms and create | |
118 | * the filesystem lockspace in the DLM. The lockspace should be | |
119 | * stored on cc_lockspace. Any other information can be stored on | |
120 | * cc_private. | |
121 | * | |
122 | * ->connect() must not return until it is guaranteed that | |
123 | * | |
25985edc | 124 | * - Node down notifications for the filesystem will be received |
e3dad42b JB |
125 | * and passed to conn->cc_recovery_handler(). |
126 | * - Locking requests for the filesystem will be processed. | |
127 | */ | |
128 | int (*connect)(struct ocfs2_cluster_connection *conn); | |
129 | ||
130 | /* | |
131 | * The fs code calls ocfs2_cluster_disconnect() when a filesystem | |
132 | * no longer needs cluster services. All DLM locks have been | |
133 | * dropped, and recovery notification is being ignored by the | |
134 | * fs code. The stack must disengage from the DLM and discontinue | |
135 | * recovery notification. | |
136 | * | |
137 | * Once ->disconnect() has returned, the connection structure will | |
138 | * be freed. Thus, a stack must not return from ->disconnect() | |
139 | * until it will no longer reference the conn pointer. | |
286eaa95 | 140 | * |
2c39450b JB |
141 | * Once this call returns, the stack glue will be dropping this |
142 | * connection's reference on the module. | |
e3dad42b | 143 | */ |
2c39450b | 144 | int (*disconnect)(struct ocfs2_cluster_connection *conn); |
e3dad42b JB |
145 | |
146 | /* | |
147 | * ->this_node() returns the cluster's unique identifier for the | |
148 | * local node. | |
149 | */ | |
3e834151 GR |
150 | int (*this_node)(struct ocfs2_cluster_connection *conn, |
151 | unsigned int *node); | |
e3dad42b JB |
152 | |
153 | /* | |
154 | * Call the underlying dlm lock function. The ->dlm_lock() | |
155 | * callback should convert the flags and mode as appropriate. | |
156 | * | |
157 | * ast and bast functions are not part of the call because the | |
158 | * stack will likely want to wrap ast and bast calls before passing | |
a796d286 JB |
159 | * them to stack->sp_proto. There is no astarg. The lksb will |
160 | * be passed back to the ast and bast functions. The caller can | |
161 | * use this to find their object. | |
e3dad42b JB |
162 | */ |
163 | int (*dlm_lock)(struct ocfs2_cluster_connection *conn, | |
164 | int mode, | |
c0e41338 | 165 | struct ocfs2_dlm_lksb *lksb, |
e3dad42b JB |
166 | u32 flags, |
167 | void *name, | |
a796d286 | 168 | unsigned int namelen); |
e3dad42b JB |
169 | |
170 | /* | |
171 | * Call the underlying dlm unlock function. The ->dlm_unlock() | |
172 | * function should convert the flags as appropriate. | |
173 | * | |
174 | * The unlock ast is not passed, as the stack will want to wrap | |
a796d286 JB |
175 | * it before calling stack->sp_proto->lp_unlock_ast(). There is |
176 | * no astarg. The lksb will be passed back to the unlock ast | |
177 | * function. The caller can use this to find their object. | |
e3dad42b JB |
178 | */ |
179 | int (*dlm_unlock)(struct ocfs2_cluster_connection *conn, | |
c0e41338 | 180 | struct ocfs2_dlm_lksb *lksb, |
a796d286 | 181 | u32 flags); |
e3dad42b JB |
182 | |
183 | /* | |
184 | * Return the status of the current lock status block. The fs | |
185 | * code should never dereference the union. The ->lock_status() | |
186 | * callback pulls out the stack-specific lksb, converts the status | |
187 | * to a proper errno, and returns it. | |
188 | */ | |
c0e41338 | 189 | int (*lock_status)(struct ocfs2_dlm_lksb *lksb); |
e3dad42b | 190 | |
1c520dfb JB |
191 | /* |
192 | * Return non-zero if the LVB is valid. | |
193 | */ | |
c0e41338 | 194 | int (*lvb_valid)(struct ocfs2_dlm_lksb *lksb); |
1c520dfb | 195 | |
e3dad42b JB |
196 | /* |
197 | * Pull the lvb pointer off of the stack-specific lksb. | |
198 | */ | |
c0e41338 | 199 | void *(*lock_lvb)(struct ocfs2_dlm_lksb *lksb); |
e3dad42b | 200 | |
53da4939 MF |
201 | /* |
202 | * Cluster-aware posix locks | |
203 | * | |
204 | * This is NULL for stacks which do not support posix locks. | |
205 | */ | |
206 | int (*plock)(struct ocfs2_cluster_connection *conn, | |
207 | u64 ino, | |
208 | struct file *file, | |
209 | int cmd, | |
210 | struct file_lock *fl); | |
211 | ||
e3dad42b JB |
212 | /* |
213 | * This is an optoinal debugging hook. If provided, the | |
214 | * stack can dump debugging information about this lock. | |
215 | */ | |
c0e41338 | 216 | void (*dump_lksb)(struct ocfs2_dlm_lksb *lksb); |
e3dad42b JB |
217 | }; |
218 | ||
286eaa95 JB |
219 | /* |
220 | * Each stack plugin must describe itself by registering a | |
221 | * ocfs2_stack_plugin structure. This is only seen by stackglue and the | |
222 | * stack driver. | |
223 | */ | |
224 | struct ocfs2_stack_plugin { | |
225 | char *sp_name; | |
226 | struct ocfs2_stack_operations *sp_ops; | |
227 | struct module *sp_owner; | |
228 | ||
229 | /* These are managed by the stackglue code. */ | |
230 | struct list_head sp_list; | |
231 | unsigned int sp_count; | |
e603cfb0 | 232 | struct ocfs2_protocol_version sp_max_proto; |
286eaa95 JB |
233 | }; |
234 | ||
235 | ||
236 | /* Used by the filesystem */ | |
9c6c877c | 237 | int ocfs2_cluster_connect(const char *stack_name, |
c74a3bdd GR |
238 | const char *cluster_name, |
239 | int cluster_name_len, | |
9c6c877c | 240 | const char *group, |
4670c46d | 241 | int grouplen, |
553b5eb9 | 242 | struct ocfs2_locking_protocol *lproto, |
4670c46d JB |
243 | void (*recovery_handler)(int node_num, |
244 | void *recovery_data), | |
245 | void *recovery_data, | |
246 | struct ocfs2_cluster_connection **conn); | |
cbe0e331 JB |
247 | /* |
248 | * Used by callers that don't store their stack name. They must ensure | |
249 | * all nodes have the same stack. | |
250 | */ | |
251 | int ocfs2_cluster_connect_agnostic(const char *group, | |
252 | int grouplen, | |
253 | struct ocfs2_locking_protocol *lproto, | |
254 | void (*recovery_handler)(int node_num, | |
255 | void *recovery_data), | |
256 | void *recovery_data, | |
257 | struct ocfs2_cluster_connection **conn); | |
286eaa95 JB |
258 | int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn, |
259 | int hangup_pending); | |
6953b4c0 | 260 | void ocfs2_cluster_hangup(const char *group, int grouplen); |
3e834151 GR |
261 | int ocfs2_cluster_this_node(struct ocfs2_cluster_connection *conn, |
262 | unsigned int *node); | |
4670c46d | 263 | |
cf4d8d75 | 264 | struct ocfs2_lock_res; |
4670c46d | 265 | int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn, |
24ef1815 | 266 | int mode, |
c0e41338 | 267 | struct ocfs2_dlm_lksb *lksb, |
24ef1815 JB |
268 | u32 flags, |
269 | void *name, | |
a796d286 | 270 | unsigned int namelen); |
4670c46d | 271 | int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn, |
c0e41338 | 272 | struct ocfs2_dlm_lksb *lksb, |
a796d286 | 273 | u32 flags); |
24ef1815 | 274 | |
c0e41338 JB |
275 | int ocfs2_dlm_lock_status(struct ocfs2_dlm_lksb *lksb); |
276 | int ocfs2_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb); | |
277 | void *ocfs2_dlm_lvb(struct ocfs2_dlm_lksb *lksb); | |
278 | void ocfs2_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb); | |
8f2c9c1b | 279 | |
53da4939 MF |
280 | int ocfs2_stack_supports_plocks(void); |
281 | int ocfs2_plock(struct ocfs2_cluster_connection *conn, u64 ino, | |
282 | struct file *file, int cmd, struct file_lock *fl); | |
283 | ||
553b5eb9 | 284 | void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_proto); |
24ef1815 | 285 | |
286eaa95 JB |
286 | |
287 | /* Used by stack plugins */ | |
288 | int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin); | |
289 | void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin); | |
3878f110 | 290 | |
9dde5e4f GH |
291 | extern struct kset *ocfs2_kset; |
292 | ||
24ef1815 | 293 | #endif /* STACKGLUE_H */ |