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e7fd4179 DT |
1 | /****************************************************************************** |
2 | ******************************************************************************* | |
3 | ** | |
4 | ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
60f98d18 | 5 | ** Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved. |
e7fd4179 DT |
6 | ** |
7 | ** This copyrighted material is made available to anyone wishing to use, | |
8 | ** modify, copy, or redistribute it subject to the terms and conditions | |
9 | ** of the GNU General Public License v.2. | |
10 | ** | |
11 | ******************************************************************************* | |
12 | ******************************************************************************/ | |
13 | ||
14 | #ifndef __DLM_DOT_H__ | |
15 | #define __DLM_DOT_H__ | |
16 | ||
17 | /* | |
18 | * Interface to Distributed Lock Manager (DLM) | |
19 | * routines and structures to use DLM lockspaces | |
20 | */ | |
21 | ||
d69a3ad6 JB |
22 | /* Lock levels and flags are here */ |
23 | #include <linux/dlmconstants.h> | |
c1c76743 | 24 | #include <linux/types.h> |
e7fd4179 | 25 | |
e7fd4179 DT |
26 | typedef void dlm_lockspace_t; |
27 | ||
e7fd4179 DT |
28 | /* |
29 | * Lock status block | |
30 | * | |
31 | * Use this structure to specify the contents of the lock value block. For a | |
32 | * conversion request, this structure is used to specify the lock ID of the | |
33 | * lock. DLM writes the status of the lock request and the lock ID assigned | |
34 | * to the request in the lock status block. | |
35 | * | |
36 | * sb_lkid: the returned lock ID. It is set on new (non-conversion) requests. | |
37 | * It is available when dlm_lock returns. | |
38 | * | |
39 | * sb_lvbptr: saves or returns the contents of the lock's LVB according to rules | |
40 | * shown for the DLM_LKF_VALBLK flag. | |
41 | * | |
42 | * sb_flags: DLM_SBF_DEMOTED is returned if in the process of promoting a lock, | |
43 | * it was first demoted to NL to avoid conversion deadlock. | |
44 | * DLM_SBF_VALNOTVALID is returned if the resource's LVB is marked invalid. | |
45 | * | |
46 | * sb_status: the returned status of the lock request set prior to AST | |
47 | * execution. Possible return values: | |
48 | * | |
49 | * 0 if lock request was successful | |
50 | * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE | |
e7fd4179 DT |
51 | * -DLM_EUNLOCK if unlock request was successful |
52 | * -DLM_ECANCEL if a cancel completed successfully | |
269cddd4 SW |
53 | * -EDEADLK if a deadlock was detected |
54 | * -ETIMEDOUT if the lock request was canceled due to a timeout | |
e7fd4179 DT |
55 | */ |
56 | ||
57 | #define DLM_SBF_DEMOTED 0x01 | |
58 | #define DLM_SBF_VALNOTVALID 0x02 | |
59 | #define DLM_SBF_ALTMODE 0x04 | |
60 | ||
61 | struct dlm_lksb { | |
62 | int sb_status; | |
c1c76743 | 63 | __u32 sb_lkid; |
e7fd4179 DT |
64 | char sb_flags; |
65 | char * sb_lvbptr; | |
66 | }; | |
67 | ||
0f8e0d9a DT |
68 | /* dlm_new_lockspace() flags */ |
69 | ||
3ae1acf9 | 70 | #define DLM_LSFL_TIMEWARN 0x00000002 |
44f487a5 | 71 | #define DLM_LSFL_FS 0x00000004 |
0f8e0d9a | 72 | #define DLM_LSFL_NEWEXCL 0x00000008 |
e7fd4179 DT |
73 | |
74 | #ifdef __KERNEL__ | |
75 | ||
60f98d18 DT |
76 | struct dlm_slot { |
77 | int nodeid; /* 1 to MAX_INT */ | |
78 | int slot; /* 1 to MAX_INT */ | |
79 | }; | |
80 | ||
81 | /* | |
82 | * recover_prep: called before the dlm begins lock recovery. | |
83 | * Notfies lockspace user that locks from failed members will be granted. | |
84 | * recover_slot: called after recover_prep and before recover_done. | |
85 | * Identifies a failed lockspace member. | |
86 | * recover_done: called after the dlm completes lock recovery. | |
87 | * Identifies lockspace members and lockspace generation number. | |
88 | */ | |
89 | ||
90 | struct dlm_lockspace_ops { | |
91 | void (*recover_prep) (void *ops_arg); | |
92 | void (*recover_slot) (void *ops_arg, struct dlm_slot *slot); | |
93 | void (*recover_done) (void *ops_arg, struct dlm_slot *slots, | |
94 | int num_slots, int our_slot, uint32_t generation); | |
95 | }; | |
96 | ||
e7fd4179 DT |
97 | /* |
98 | * dlm_new_lockspace | |
99 | * | |
60f98d18 DT |
100 | * Create/join a lockspace. |
101 | * | |
102 | * name: lockspace name, null terminated, up to DLM_LOCKSPACE_LEN (not | |
103 | * including terminating null). | |
104 | * | |
105 | * cluster: cluster name, null terminated, up to DLM_LOCKSPACE_LEN (not | |
106 | * including terminating null). Optional. When cluster is null, it | |
107 | * is not used. When set, dlm_new_lockspace() returns -EBADR if cluster | |
108 | * is not equal to the dlm cluster name. | |
109 | * | |
110 | * flags: | |
111 | * DLM_LSFL_NODIR | |
112 | * The dlm should not use a resource directory, but statically assign | |
113 | * resource mastery to nodes based on the name hash that is otherwise | |
114 | * used to select the directory node. Must be the same on all nodes. | |
115 | * DLM_LSFL_TIMEWARN | |
116 | * The dlm should emit netlink messages if locks have been waiting | |
117 | * for a configurable amount of time. (Unused.) | |
118 | * DLM_LSFL_FS | |
119 | * The lockspace user is in the kernel (i.e. filesystem). Enables | |
120 | * direct bast/cast callbacks. | |
121 | * DLM_LSFL_NEWEXCL | |
122 | * dlm_new_lockspace() should return -EEXIST if the lockspace exists. | |
123 | * | |
124 | * lvblen: length of lvb in bytes. Must be multiple of 8. | |
125 | * dlm_new_lockspace() returns an error if this does not match | |
126 | * what other nodes are using. | |
127 | * | |
128 | * ops: callbacks that indicate lockspace recovery points so the | |
129 | * caller can coordinate its recovery and know lockspace members. | |
130 | * This is only used by the initial dlm_new_lockspace() call. | |
131 | * Optional. | |
132 | * | |
133 | * ops_arg: arg for ops callbacks. | |
134 | * | |
135 | * ops_result: tells caller if the ops callbacks (if provided) will | |
136 | * be used or not. 0: will be used, -EXXX will not be used. | |
137 | * -EOPNOTSUPP: the dlm does not have recovery_callbacks enabled. | |
138 | * | |
139 | * lockspace: handle for dlm functions | |
e7fd4179 DT |
140 | */ |
141 | ||
60f98d18 DT |
142 | int dlm_new_lockspace(const char *name, const char *cluster, |
143 | uint32_t flags, int lvblen, | |
144 | const struct dlm_lockspace_ops *ops, void *ops_arg, | |
145 | int *ops_result, dlm_lockspace_t **lockspace); | |
e7fd4179 DT |
146 | |
147 | /* | |
148 | * dlm_release_lockspace | |
149 | * | |
150 | * Stop a lockspace. | |
151 | */ | |
152 | ||
153 | int dlm_release_lockspace(dlm_lockspace_t *lockspace, int force); | |
154 | ||
155 | /* | |
156 | * dlm_lock | |
157 | * | |
158 | * Make an asyncronous request to acquire or convert a lock on a named | |
159 | * resource. | |
160 | * | |
161 | * lockspace: context for the request | |
162 | * mode: the requested mode of the lock (DLM_LOCK_) | |
163 | * lksb: lock status block for input and async return values | |
164 | * flags: input flags (DLM_LKF_) | |
165 | * name: name of the resource to lock, can be binary | |
166 | * namelen: the length in bytes of the resource name (MAX_RESNAME_LEN) | |
167 | * parent: the lock ID of a parent lock or 0 if none | |
168 | * lockast: function DLM executes when it completes processing the request | |
169 | * astarg: argument passed to lockast and bast functions | |
170 | * bast: function DLM executes when this lock later blocks another request | |
171 | * | |
172 | * Returns: | |
173 | * 0 if request is successfully queued for processing | |
174 | * -EINVAL if any input parameters are invalid | |
175 | * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE | |
176 | * -ENOMEM if there is no memory to process request | |
177 | * -ENOTCONN if there is a communication error | |
178 | * | |
179 | * If the call to dlm_lock returns an error then the operation has failed and | |
180 | * the AST routine will not be called. If dlm_lock returns 0 it is still | |
181 | * possible that the lock operation will fail. The AST routine will be called | |
182 | * when the locking is complete and the status is returned in the lksb. | |
183 | * | |
184 | * If the AST routines or parameter are passed to a conversion operation then | |
185 | * they will overwrite those values that were passed to a previous dlm_lock | |
186 | * call. | |
187 | * | |
188 | * AST routines should not block (at least not for long), but may make | |
189 | * any locking calls they please. | |
190 | */ | |
191 | ||
192 | int dlm_lock(dlm_lockspace_t *lockspace, | |
193 | int mode, | |
194 | struct dlm_lksb *lksb, | |
195 | uint32_t flags, | |
196 | void *name, | |
197 | unsigned int namelen, | |
198 | uint32_t parent_lkid, | |
199 | void (*lockast) (void *astarg), | |
200 | void *astarg, | |
3bcd3687 | 201 | void (*bast) (void *astarg, int mode)); |
e7fd4179 DT |
202 | |
203 | /* | |
204 | * dlm_unlock | |
205 | * | |
206 | * Asynchronously release a lock on a resource. The AST routine is called | |
207 | * when the resource is successfully unlocked. | |
208 | * | |
209 | * lockspace: context for the request | |
210 | * lkid: the lock ID as returned in the lksb | |
211 | * flags: input flags (DLM_LKF_) | |
212 | * lksb: if NULL the lksb parameter passed to last lock request is used | |
213 | * astarg: the arg used with the completion ast for the unlock | |
214 | * | |
215 | * Returns: | |
216 | * 0 if request is successfully queued for processing | |
217 | * -EINVAL if any input parameters are invalid | |
218 | * -ENOTEMPTY if the lock still has sublocks | |
219 | * -EBUSY if the lock is waiting for a remote lock operation | |
220 | * -ENOTCONN if there is a communication error | |
221 | */ | |
222 | ||
223 | int dlm_unlock(dlm_lockspace_t *lockspace, | |
224 | uint32_t lkid, | |
225 | uint32_t flags, | |
226 | struct dlm_lksb *lksb, | |
227 | void *astarg); | |
228 | ||
229 | #endif /* __KERNEL__ */ | |
230 | ||
231 | #endif /* __DLM_DOT_H__ */ | |
232 |