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e7fd4179 DT |
1 | /****************************************************************************** |
2 | ******************************************************************************* | |
3 | ** | |
4 | ** Copyright (C) 2005 Red Hat, Inc. All rights reserved. | |
5 | ** | |
6 | ** This copyrighted material is made available to anyone wishing to use, | |
7 | ** modify, copy, or redistribute it subject to the terms and conditions | |
8 | ** of the GNU General Public License v.2. | |
9 | ** | |
10 | ******************************************************************************* | |
11 | ******************************************************************************/ | |
12 | ||
13 | /* Central locking logic has four stages: | |
14 | ||
15 | dlm_lock() | |
16 | dlm_unlock() | |
17 | ||
18 | request_lock(ls, lkb) | |
19 | convert_lock(ls, lkb) | |
20 | unlock_lock(ls, lkb) | |
21 | cancel_lock(ls, lkb) | |
22 | ||
23 | _request_lock(r, lkb) | |
24 | _convert_lock(r, lkb) | |
25 | _unlock_lock(r, lkb) | |
26 | _cancel_lock(r, lkb) | |
27 | ||
28 | do_request(r, lkb) | |
29 | do_convert(r, lkb) | |
30 | do_unlock(r, lkb) | |
31 | do_cancel(r, lkb) | |
32 | ||
33 | Stage 1 (lock, unlock) is mainly about checking input args and | |
34 | splitting into one of the four main operations: | |
35 | ||
36 | dlm_lock = request_lock | |
37 | dlm_lock+CONVERT = convert_lock | |
38 | dlm_unlock = unlock_lock | |
39 | dlm_unlock+CANCEL = cancel_lock | |
40 | ||
41 | Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is | |
42 | provided to the next stage. | |
43 | ||
44 | Stage 3, _xxxx_lock(), determines if the operation is local or remote. | |
45 | When remote, it calls send_xxxx(), when local it calls do_xxxx(). | |
46 | ||
47 | Stage 4, do_xxxx(), is the guts of the operation. It manipulates the | |
48 | given rsb and lkb and queues callbacks. | |
49 | ||
50 | For remote operations, send_xxxx() results in the corresponding do_xxxx() | |
51 | function being executed on the remote node. The connecting send/receive | |
52 | calls on local (L) and remote (R) nodes: | |
53 | ||
54 | L: send_xxxx() -> R: receive_xxxx() | |
55 | R: do_xxxx() | |
56 | L: receive_xxxx_reply() <- R: send_xxxx_reply() | |
57 | */ | |
58 | ||
59 | #include "dlm_internal.h" | |
60 | #include "memory.h" | |
61 | #include "lowcomms.h" | |
62 | #include "requestqueue.h" | |
63 | #include "util.h" | |
64 | #include "dir.h" | |
65 | #include "member.h" | |
66 | #include "lockspace.h" | |
67 | #include "ast.h" | |
68 | #include "lock.h" | |
69 | #include "rcom.h" | |
70 | #include "recover.h" | |
71 | #include "lvb_table.h" | |
72 | #include "config.h" | |
73 | ||
74 | static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
75 | static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
76 | static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
77 | static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
78 | static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
79 | static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode); | |
80 | static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
81 | static int send_remove(struct dlm_rsb *r); | |
82 | static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
83 | static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
84 | struct dlm_message *ms); | |
85 | static int receive_extralen(struct dlm_message *ms); | |
86 | ||
87 | /* | |
88 | * Lock compatibilty matrix - thanks Steve | |
89 | * UN = Unlocked state. Not really a state, used as a flag | |
90 | * PD = Padding. Used to make the matrix a nice power of two in size | |
91 | * Other states are the same as the VMS DLM. | |
92 | * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same) | |
93 | */ | |
94 | ||
95 | static const int __dlm_compat_matrix[8][8] = { | |
96 | /* UN NL CR CW PR PW EX PD */ | |
97 | {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */ | |
98 | {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */ | |
99 | {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */ | |
100 | {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */ | |
101 | {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */ | |
102 | {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */ | |
103 | {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */ | |
104 | {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ | |
105 | }; | |
106 | ||
107 | /* | |
108 | * This defines the direction of transfer of LVB data. | |
109 | * Granted mode is the row; requested mode is the column. | |
110 | * Usage: matrix[grmode+1][rqmode+1] | |
111 | * 1 = LVB is returned to the caller | |
112 | * 0 = LVB is written to the resource | |
113 | * -1 = nothing happens to the LVB | |
114 | */ | |
115 | ||
116 | const int dlm_lvb_operations[8][8] = { | |
117 | /* UN NL CR CW PR PW EX PD*/ | |
118 | { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */ | |
119 | { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */ | |
120 | { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */ | |
121 | { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */ | |
122 | { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */ | |
123 | { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */ | |
124 | { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */ | |
125 | { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */ | |
126 | }; | |
127 | EXPORT_SYMBOL_GPL(dlm_lvb_operations); | |
128 | ||
129 | #define modes_compat(gr, rq) \ | |
130 | __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1] | |
131 | ||
132 | int dlm_modes_compat(int mode1, int mode2) | |
133 | { | |
134 | return __dlm_compat_matrix[mode1 + 1][mode2 + 1]; | |
135 | } | |
136 | ||
137 | /* | |
138 | * Compatibility matrix for conversions with QUECVT set. | |
139 | * Granted mode is the row; requested mode is the column. | |
140 | * Usage: matrix[grmode+1][rqmode+1] | |
141 | */ | |
142 | ||
143 | static const int __quecvt_compat_matrix[8][8] = { | |
144 | /* UN NL CR CW PR PW EX PD */ | |
145 | {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */ | |
146 | {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */ | |
147 | {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */ | |
148 | {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */ | |
149 | {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */ | |
150 | {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */ | |
151 | {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */ | |
152 | {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ | |
153 | }; | |
154 | ||
155 | static void dlm_print_lkb(struct dlm_lkb *lkb) | |
156 | { | |
157 | printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n" | |
158 | " status %d rqmode %d grmode %d wait_type %d ast_type %d\n", | |
159 | lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags, | |
160 | lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode, | |
161 | lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_ast_type); | |
162 | } | |
163 | ||
164 | void dlm_print_rsb(struct dlm_rsb *r) | |
165 | { | |
166 | printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n", | |
167 | r->res_nodeid, r->res_flags, r->res_first_lkid, | |
168 | r->res_recover_locks_count, r->res_name); | |
169 | } | |
170 | ||
171 | /* Threads cannot use the lockspace while it's being recovered */ | |
172 | ||
173 | static inline void lock_recovery(struct dlm_ls *ls) | |
174 | { | |
175 | down_read(&ls->ls_in_recovery); | |
176 | } | |
177 | ||
178 | static inline void unlock_recovery(struct dlm_ls *ls) | |
179 | { | |
180 | up_read(&ls->ls_in_recovery); | |
181 | } | |
182 | ||
183 | static inline int lock_recovery_try(struct dlm_ls *ls) | |
184 | { | |
185 | return down_read_trylock(&ls->ls_in_recovery); | |
186 | } | |
187 | ||
188 | static inline int can_be_queued(struct dlm_lkb *lkb) | |
189 | { | |
190 | return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE); | |
191 | } | |
192 | ||
193 | static inline int force_blocking_asts(struct dlm_lkb *lkb) | |
194 | { | |
195 | return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST); | |
196 | } | |
197 | ||
198 | static inline int is_demoted(struct dlm_lkb *lkb) | |
199 | { | |
200 | return (lkb->lkb_sbflags & DLM_SBF_DEMOTED); | |
201 | } | |
202 | ||
203 | static inline int is_remote(struct dlm_rsb *r) | |
204 | { | |
205 | DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r);); | |
206 | return !!r->res_nodeid; | |
207 | } | |
208 | ||
209 | static inline int is_process_copy(struct dlm_lkb *lkb) | |
210 | { | |
211 | return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY)); | |
212 | } | |
213 | ||
214 | static inline int is_master_copy(struct dlm_lkb *lkb) | |
215 | { | |
216 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
217 | DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb);); | |
90135925 | 218 | return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0; |
e7fd4179 DT |
219 | } |
220 | ||
221 | static inline int middle_conversion(struct dlm_lkb *lkb) | |
222 | { | |
223 | if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) || | |
224 | (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW)) | |
90135925 DT |
225 | return 1; |
226 | return 0; | |
e7fd4179 DT |
227 | } |
228 | ||
229 | static inline int down_conversion(struct dlm_lkb *lkb) | |
230 | { | |
231 | return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode); | |
232 | } | |
233 | ||
234 | static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
235 | { | |
236 | if (is_master_copy(lkb)) | |
237 | return; | |
238 | ||
239 | DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb);); | |
240 | ||
241 | lkb->lkb_lksb->sb_status = rv; | |
242 | lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags; | |
243 | ||
244 | dlm_add_ast(lkb, AST_COMP); | |
245 | } | |
246 | ||
247 | static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode) | |
248 | { | |
249 | if (is_master_copy(lkb)) | |
250 | send_bast(r, lkb, rqmode); | |
251 | else { | |
252 | lkb->lkb_bastmode = rqmode; | |
253 | dlm_add_ast(lkb, AST_BAST); | |
254 | } | |
255 | } | |
256 | ||
257 | /* | |
258 | * Basic operations on rsb's and lkb's | |
259 | */ | |
260 | ||
261 | static struct dlm_rsb *create_rsb(struct dlm_ls *ls, char *name, int len) | |
262 | { | |
263 | struct dlm_rsb *r; | |
264 | ||
265 | r = allocate_rsb(ls, len); | |
266 | if (!r) | |
267 | return NULL; | |
268 | ||
269 | r->res_ls = ls; | |
270 | r->res_length = len; | |
271 | memcpy(r->res_name, name, len); | |
90135925 | 272 | mutex_init(&r->res_mutex); |
e7fd4179 DT |
273 | |
274 | INIT_LIST_HEAD(&r->res_lookup); | |
275 | INIT_LIST_HEAD(&r->res_grantqueue); | |
276 | INIT_LIST_HEAD(&r->res_convertqueue); | |
277 | INIT_LIST_HEAD(&r->res_waitqueue); | |
278 | INIT_LIST_HEAD(&r->res_root_list); | |
279 | INIT_LIST_HEAD(&r->res_recover_list); | |
280 | ||
281 | return r; | |
282 | } | |
283 | ||
284 | static int search_rsb_list(struct list_head *head, char *name, int len, | |
285 | unsigned int flags, struct dlm_rsb **r_ret) | |
286 | { | |
287 | struct dlm_rsb *r; | |
288 | int error = 0; | |
289 | ||
290 | list_for_each_entry(r, head, res_hashchain) { | |
291 | if (len == r->res_length && !memcmp(name, r->res_name, len)) | |
292 | goto found; | |
293 | } | |
294 | return -ENOENT; | |
295 | ||
296 | found: | |
297 | if (r->res_nodeid && (flags & R_MASTER)) | |
298 | error = -ENOTBLK; | |
299 | *r_ret = r; | |
300 | return error; | |
301 | } | |
302 | ||
303 | static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b, | |
304 | unsigned int flags, struct dlm_rsb **r_ret) | |
305 | { | |
306 | struct dlm_rsb *r; | |
307 | int error; | |
308 | ||
309 | error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r); | |
310 | if (!error) { | |
311 | kref_get(&r->res_ref); | |
312 | goto out; | |
313 | } | |
314 | error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r); | |
315 | if (error) | |
316 | goto out; | |
317 | ||
318 | list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list); | |
319 | ||
320 | if (dlm_no_directory(ls)) | |
321 | goto out; | |
322 | ||
323 | if (r->res_nodeid == -1) { | |
324 | rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); | |
325 | r->res_first_lkid = 0; | |
326 | } else if (r->res_nodeid > 0) { | |
327 | rsb_set_flag(r, RSB_MASTER_UNCERTAIN); | |
328 | r->res_first_lkid = 0; | |
329 | } else { | |
330 | DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r);); | |
331 | DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),); | |
332 | } | |
333 | out: | |
334 | *r_ret = r; | |
335 | return error; | |
336 | } | |
337 | ||
338 | static int search_rsb(struct dlm_ls *ls, char *name, int len, int b, | |
339 | unsigned int flags, struct dlm_rsb **r_ret) | |
340 | { | |
341 | int error; | |
342 | write_lock(&ls->ls_rsbtbl[b].lock); | |
343 | error = _search_rsb(ls, name, len, b, flags, r_ret); | |
344 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
345 | return error; | |
346 | } | |
347 | ||
348 | /* | |
349 | * Find rsb in rsbtbl and potentially create/add one | |
350 | * | |
351 | * Delaying the release of rsb's has a similar benefit to applications keeping | |
352 | * NL locks on an rsb, but without the guarantee that the cached master value | |
353 | * will still be valid when the rsb is reused. Apps aren't always smart enough | |
354 | * to keep NL locks on an rsb that they may lock again shortly; this can lead | |
355 | * to excessive master lookups and removals if we don't delay the release. | |
356 | * | |
357 | * Searching for an rsb means looking through both the normal list and toss | |
358 | * list. When found on the toss list the rsb is moved to the normal list with | |
359 | * ref count of 1; when found on normal list the ref count is incremented. | |
360 | */ | |
361 | ||
362 | static int find_rsb(struct dlm_ls *ls, char *name, int namelen, | |
363 | unsigned int flags, struct dlm_rsb **r_ret) | |
364 | { | |
365 | struct dlm_rsb *r, *tmp; | |
366 | uint32_t hash, bucket; | |
367 | int error = 0; | |
368 | ||
369 | if (dlm_no_directory(ls)) | |
370 | flags |= R_CREATE; | |
371 | ||
372 | hash = jhash(name, namelen, 0); | |
373 | bucket = hash & (ls->ls_rsbtbl_size - 1); | |
374 | ||
375 | error = search_rsb(ls, name, namelen, bucket, flags, &r); | |
376 | if (!error) | |
377 | goto out; | |
378 | ||
379 | if (error == -ENOENT && !(flags & R_CREATE)) | |
380 | goto out; | |
381 | ||
382 | /* the rsb was found but wasn't a master copy */ | |
383 | if (error == -ENOTBLK) | |
384 | goto out; | |
385 | ||
386 | error = -ENOMEM; | |
387 | r = create_rsb(ls, name, namelen); | |
388 | if (!r) | |
389 | goto out; | |
390 | ||
391 | r->res_hash = hash; | |
392 | r->res_bucket = bucket; | |
393 | r->res_nodeid = -1; | |
394 | kref_init(&r->res_ref); | |
395 | ||
396 | /* With no directory, the master can be set immediately */ | |
397 | if (dlm_no_directory(ls)) { | |
398 | int nodeid = dlm_dir_nodeid(r); | |
399 | if (nodeid == dlm_our_nodeid()) | |
400 | nodeid = 0; | |
401 | r->res_nodeid = nodeid; | |
402 | } | |
403 | ||
404 | write_lock(&ls->ls_rsbtbl[bucket].lock); | |
405 | error = _search_rsb(ls, name, namelen, bucket, 0, &tmp); | |
406 | if (!error) { | |
407 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
408 | free_rsb(r); | |
409 | r = tmp; | |
410 | goto out; | |
411 | } | |
412 | list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list); | |
413 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
414 | error = 0; | |
415 | out: | |
416 | *r_ret = r; | |
417 | return error; | |
418 | } | |
419 | ||
420 | int dlm_find_rsb(struct dlm_ls *ls, char *name, int namelen, | |
421 | unsigned int flags, struct dlm_rsb **r_ret) | |
422 | { | |
423 | return find_rsb(ls, name, namelen, flags, r_ret); | |
424 | } | |
425 | ||
426 | /* This is only called to add a reference when the code already holds | |
427 | a valid reference to the rsb, so there's no need for locking. */ | |
428 | ||
429 | static inline void hold_rsb(struct dlm_rsb *r) | |
430 | { | |
431 | kref_get(&r->res_ref); | |
432 | } | |
433 | ||
434 | void dlm_hold_rsb(struct dlm_rsb *r) | |
435 | { | |
436 | hold_rsb(r); | |
437 | } | |
438 | ||
439 | static void toss_rsb(struct kref *kref) | |
440 | { | |
441 | struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); | |
442 | struct dlm_ls *ls = r->res_ls; | |
443 | ||
444 | DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r);); | |
445 | kref_init(&r->res_ref); | |
446 | list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss); | |
447 | r->res_toss_time = jiffies; | |
448 | if (r->res_lvbptr) { | |
449 | free_lvb(r->res_lvbptr); | |
450 | r->res_lvbptr = NULL; | |
451 | } | |
452 | } | |
453 | ||
454 | /* When all references to the rsb are gone it's transfered to | |
455 | the tossed list for later disposal. */ | |
456 | ||
457 | static void put_rsb(struct dlm_rsb *r) | |
458 | { | |
459 | struct dlm_ls *ls = r->res_ls; | |
460 | uint32_t bucket = r->res_bucket; | |
461 | ||
462 | write_lock(&ls->ls_rsbtbl[bucket].lock); | |
463 | kref_put(&r->res_ref, toss_rsb); | |
464 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
465 | } | |
466 | ||
467 | void dlm_put_rsb(struct dlm_rsb *r) | |
468 | { | |
469 | put_rsb(r); | |
470 | } | |
471 | ||
472 | /* See comment for unhold_lkb */ | |
473 | ||
474 | static void unhold_rsb(struct dlm_rsb *r) | |
475 | { | |
476 | int rv; | |
477 | rv = kref_put(&r->res_ref, toss_rsb); | |
478 | DLM_ASSERT(!rv, dlm_print_rsb(r);); | |
479 | } | |
480 | ||
481 | static void kill_rsb(struct kref *kref) | |
482 | { | |
483 | struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); | |
484 | ||
485 | /* All work is done after the return from kref_put() so we | |
486 | can release the write_lock before the remove and free. */ | |
487 | ||
488 | DLM_ASSERT(list_empty(&r->res_lookup),); | |
489 | DLM_ASSERT(list_empty(&r->res_grantqueue),); | |
490 | DLM_ASSERT(list_empty(&r->res_convertqueue),); | |
491 | DLM_ASSERT(list_empty(&r->res_waitqueue),); | |
492 | DLM_ASSERT(list_empty(&r->res_root_list),); | |
493 | DLM_ASSERT(list_empty(&r->res_recover_list),); | |
494 | } | |
495 | ||
496 | /* Attaching/detaching lkb's from rsb's is for rsb reference counting. | |
497 | The rsb must exist as long as any lkb's for it do. */ | |
498 | ||
499 | static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
500 | { | |
501 | hold_rsb(r); | |
502 | lkb->lkb_resource = r; | |
503 | } | |
504 | ||
505 | static void detach_lkb(struct dlm_lkb *lkb) | |
506 | { | |
507 | if (lkb->lkb_resource) { | |
508 | put_rsb(lkb->lkb_resource); | |
509 | lkb->lkb_resource = NULL; | |
510 | } | |
511 | } | |
512 | ||
513 | static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) | |
514 | { | |
515 | struct dlm_lkb *lkb, *tmp; | |
516 | uint32_t lkid = 0; | |
517 | uint16_t bucket; | |
518 | ||
519 | lkb = allocate_lkb(ls); | |
520 | if (!lkb) | |
521 | return -ENOMEM; | |
522 | ||
523 | lkb->lkb_nodeid = -1; | |
524 | lkb->lkb_grmode = DLM_LOCK_IV; | |
525 | kref_init(&lkb->lkb_ref); | |
526 | ||
527 | get_random_bytes(&bucket, sizeof(bucket)); | |
528 | bucket &= (ls->ls_lkbtbl_size - 1); | |
529 | ||
530 | write_lock(&ls->ls_lkbtbl[bucket].lock); | |
531 | ||
532 | /* counter can roll over so we must verify lkid is not in use */ | |
533 | ||
534 | while (lkid == 0) { | |
535 | lkid = bucket | (ls->ls_lkbtbl[bucket].counter++ << 16); | |
536 | ||
537 | list_for_each_entry(tmp, &ls->ls_lkbtbl[bucket].list, | |
538 | lkb_idtbl_list) { | |
539 | if (tmp->lkb_id != lkid) | |
540 | continue; | |
541 | lkid = 0; | |
542 | break; | |
543 | } | |
544 | } | |
545 | ||
546 | lkb->lkb_id = lkid; | |
547 | list_add(&lkb->lkb_idtbl_list, &ls->ls_lkbtbl[bucket].list); | |
548 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
549 | ||
550 | *lkb_ret = lkb; | |
551 | return 0; | |
552 | } | |
553 | ||
554 | static struct dlm_lkb *__find_lkb(struct dlm_ls *ls, uint32_t lkid) | |
555 | { | |
556 | uint16_t bucket = lkid & 0xFFFF; | |
557 | struct dlm_lkb *lkb; | |
558 | ||
559 | list_for_each_entry(lkb, &ls->ls_lkbtbl[bucket].list, lkb_idtbl_list) { | |
560 | if (lkb->lkb_id == lkid) | |
561 | return lkb; | |
562 | } | |
563 | return NULL; | |
564 | } | |
565 | ||
566 | static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret) | |
567 | { | |
568 | struct dlm_lkb *lkb; | |
569 | uint16_t bucket = lkid & 0xFFFF; | |
570 | ||
571 | if (bucket >= ls->ls_lkbtbl_size) | |
572 | return -EBADSLT; | |
573 | ||
574 | read_lock(&ls->ls_lkbtbl[bucket].lock); | |
575 | lkb = __find_lkb(ls, lkid); | |
576 | if (lkb) | |
577 | kref_get(&lkb->lkb_ref); | |
578 | read_unlock(&ls->ls_lkbtbl[bucket].lock); | |
579 | ||
580 | *lkb_ret = lkb; | |
581 | return lkb ? 0 : -ENOENT; | |
582 | } | |
583 | ||
584 | static void kill_lkb(struct kref *kref) | |
585 | { | |
586 | struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref); | |
587 | ||
588 | /* All work is done after the return from kref_put() so we | |
589 | can release the write_lock before the detach_lkb */ | |
590 | ||
591 | DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); | |
592 | } | |
593 | ||
594 | static int put_lkb(struct dlm_lkb *lkb) | |
595 | { | |
596 | struct dlm_ls *ls = lkb->lkb_resource->res_ls; | |
597 | uint16_t bucket = lkb->lkb_id & 0xFFFF; | |
598 | ||
599 | write_lock(&ls->ls_lkbtbl[bucket].lock); | |
600 | if (kref_put(&lkb->lkb_ref, kill_lkb)) { | |
601 | list_del(&lkb->lkb_idtbl_list); | |
602 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
603 | ||
604 | detach_lkb(lkb); | |
605 | ||
606 | /* for local/process lkbs, lvbptr points to caller's lksb */ | |
607 | if (lkb->lkb_lvbptr && is_master_copy(lkb)) | |
608 | free_lvb(lkb->lkb_lvbptr); | |
609 | if (lkb->lkb_range) | |
610 | free_range(lkb->lkb_range); | |
611 | free_lkb(lkb); | |
612 | return 1; | |
613 | } else { | |
614 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
615 | return 0; | |
616 | } | |
617 | } | |
618 | ||
619 | int dlm_put_lkb(struct dlm_lkb *lkb) | |
620 | { | |
621 | return put_lkb(lkb); | |
622 | } | |
623 | ||
624 | /* This is only called to add a reference when the code already holds | |
625 | a valid reference to the lkb, so there's no need for locking. */ | |
626 | ||
627 | static inline void hold_lkb(struct dlm_lkb *lkb) | |
628 | { | |
629 | kref_get(&lkb->lkb_ref); | |
630 | } | |
631 | ||
632 | /* This is called when we need to remove a reference and are certain | |
633 | it's not the last ref. e.g. del_lkb is always called between a | |
634 | find_lkb/put_lkb and is always the inverse of a previous add_lkb. | |
635 | put_lkb would work fine, but would involve unnecessary locking */ | |
636 | ||
637 | static inline void unhold_lkb(struct dlm_lkb *lkb) | |
638 | { | |
639 | int rv; | |
640 | rv = kref_put(&lkb->lkb_ref, kill_lkb); | |
641 | DLM_ASSERT(!rv, dlm_print_lkb(lkb);); | |
642 | } | |
643 | ||
644 | static void lkb_add_ordered(struct list_head *new, struct list_head *head, | |
645 | int mode) | |
646 | { | |
647 | struct dlm_lkb *lkb = NULL; | |
648 | ||
649 | list_for_each_entry(lkb, head, lkb_statequeue) | |
650 | if (lkb->lkb_rqmode < mode) | |
651 | break; | |
652 | ||
653 | if (!lkb) | |
654 | list_add_tail(new, head); | |
655 | else | |
656 | __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue); | |
657 | } | |
658 | ||
659 | /* add/remove lkb to rsb's grant/convert/wait queue */ | |
660 | ||
661 | static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status) | |
662 | { | |
663 | kref_get(&lkb->lkb_ref); | |
664 | ||
665 | DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); | |
666 | ||
667 | lkb->lkb_status = status; | |
668 | ||
669 | switch (status) { | |
670 | case DLM_LKSTS_WAITING: | |
671 | if (lkb->lkb_exflags & DLM_LKF_HEADQUE) | |
672 | list_add(&lkb->lkb_statequeue, &r->res_waitqueue); | |
673 | else | |
674 | list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue); | |
675 | break; | |
676 | case DLM_LKSTS_GRANTED: | |
677 | /* convention says granted locks kept in order of grmode */ | |
678 | lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue, | |
679 | lkb->lkb_grmode); | |
680 | break; | |
681 | case DLM_LKSTS_CONVERT: | |
682 | if (lkb->lkb_exflags & DLM_LKF_HEADQUE) | |
683 | list_add(&lkb->lkb_statequeue, &r->res_convertqueue); | |
684 | else | |
685 | list_add_tail(&lkb->lkb_statequeue, | |
686 | &r->res_convertqueue); | |
687 | break; | |
688 | default: | |
689 | DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status);); | |
690 | } | |
691 | } | |
692 | ||
693 | static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
694 | { | |
695 | lkb->lkb_status = 0; | |
696 | list_del(&lkb->lkb_statequeue); | |
697 | unhold_lkb(lkb); | |
698 | } | |
699 | ||
700 | static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts) | |
701 | { | |
702 | hold_lkb(lkb); | |
703 | del_lkb(r, lkb); | |
704 | add_lkb(r, lkb, sts); | |
705 | unhold_lkb(lkb); | |
706 | } | |
707 | ||
708 | /* add/remove lkb from global waiters list of lkb's waiting for | |
709 | a reply from a remote node */ | |
710 | ||
711 | static void add_to_waiters(struct dlm_lkb *lkb, int mstype) | |
712 | { | |
713 | struct dlm_ls *ls = lkb->lkb_resource->res_ls; | |
714 | ||
90135925 | 715 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
716 | if (lkb->lkb_wait_type) { |
717 | log_print("add_to_waiters error %d", lkb->lkb_wait_type); | |
718 | goto out; | |
719 | } | |
720 | lkb->lkb_wait_type = mstype; | |
721 | kref_get(&lkb->lkb_ref); | |
722 | list_add(&lkb->lkb_wait_reply, &ls->ls_waiters); | |
723 | out: | |
90135925 | 724 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
725 | } |
726 | ||
727 | static int _remove_from_waiters(struct dlm_lkb *lkb) | |
728 | { | |
729 | int error = 0; | |
730 | ||
731 | if (!lkb->lkb_wait_type) { | |
732 | log_print("remove_from_waiters error"); | |
733 | error = -EINVAL; | |
734 | goto out; | |
735 | } | |
736 | lkb->lkb_wait_type = 0; | |
737 | list_del(&lkb->lkb_wait_reply); | |
738 | unhold_lkb(lkb); | |
739 | out: | |
740 | return error; | |
741 | } | |
742 | ||
743 | static int remove_from_waiters(struct dlm_lkb *lkb) | |
744 | { | |
745 | struct dlm_ls *ls = lkb->lkb_resource->res_ls; | |
746 | int error; | |
747 | ||
90135925 | 748 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 | 749 | error = _remove_from_waiters(lkb); |
90135925 | 750 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
751 | return error; |
752 | } | |
753 | ||
754 | static void dir_remove(struct dlm_rsb *r) | |
755 | { | |
756 | int to_nodeid; | |
757 | ||
758 | if (dlm_no_directory(r->res_ls)) | |
759 | return; | |
760 | ||
761 | to_nodeid = dlm_dir_nodeid(r); | |
762 | if (to_nodeid != dlm_our_nodeid()) | |
763 | send_remove(r); | |
764 | else | |
765 | dlm_dir_remove_entry(r->res_ls, to_nodeid, | |
766 | r->res_name, r->res_length); | |
767 | } | |
768 | ||
769 | /* FIXME: shouldn't this be able to exit as soon as one non-due rsb is | |
770 | found since they are in order of newest to oldest? */ | |
771 | ||
772 | static int shrink_bucket(struct dlm_ls *ls, int b) | |
773 | { | |
774 | struct dlm_rsb *r; | |
775 | int count = 0, found; | |
776 | ||
777 | for (;;) { | |
90135925 | 778 | found = 0; |
e7fd4179 DT |
779 | write_lock(&ls->ls_rsbtbl[b].lock); |
780 | list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss, | |
781 | res_hashchain) { | |
782 | if (!time_after_eq(jiffies, r->res_toss_time + | |
783 | dlm_config.toss_secs * HZ)) | |
784 | continue; | |
90135925 | 785 | found = 1; |
e7fd4179 DT |
786 | break; |
787 | } | |
788 | ||
789 | if (!found) { | |
790 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
791 | break; | |
792 | } | |
793 | ||
794 | if (kref_put(&r->res_ref, kill_rsb)) { | |
795 | list_del(&r->res_hashchain); | |
796 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
797 | ||
798 | if (is_master(r)) | |
799 | dir_remove(r); | |
800 | free_rsb(r); | |
801 | count++; | |
802 | } else { | |
803 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
804 | log_error(ls, "tossed rsb in use %s", r->res_name); | |
805 | } | |
806 | } | |
807 | ||
808 | return count; | |
809 | } | |
810 | ||
811 | void dlm_scan_rsbs(struct dlm_ls *ls) | |
812 | { | |
813 | int i; | |
814 | ||
815 | if (dlm_locking_stopped(ls)) | |
816 | return; | |
817 | ||
818 | for (i = 0; i < ls->ls_rsbtbl_size; i++) { | |
819 | shrink_bucket(ls, i); | |
820 | cond_resched(); | |
821 | } | |
822 | } | |
823 | ||
824 | /* lkb is master or local copy */ | |
825 | ||
826 | static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
827 | { | |
828 | int b, len = r->res_ls->ls_lvblen; | |
829 | ||
830 | /* b=1 lvb returned to caller | |
831 | b=0 lvb written to rsb or invalidated | |
832 | b=-1 do nothing */ | |
833 | ||
834 | b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; | |
835 | ||
836 | if (b == 1) { | |
837 | if (!lkb->lkb_lvbptr) | |
838 | return; | |
839 | ||
840 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
841 | return; | |
842 | ||
843 | if (!r->res_lvbptr) | |
844 | return; | |
845 | ||
846 | memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len); | |
847 | lkb->lkb_lvbseq = r->res_lvbseq; | |
848 | ||
849 | } else if (b == 0) { | |
850 | if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) { | |
851 | rsb_set_flag(r, RSB_VALNOTVALID); | |
852 | return; | |
853 | } | |
854 | ||
855 | if (!lkb->lkb_lvbptr) | |
856 | return; | |
857 | ||
858 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
859 | return; | |
860 | ||
861 | if (!r->res_lvbptr) | |
862 | r->res_lvbptr = allocate_lvb(r->res_ls); | |
863 | ||
864 | if (!r->res_lvbptr) | |
865 | return; | |
866 | ||
867 | memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len); | |
868 | r->res_lvbseq++; | |
869 | lkb->lkb_lvbseq = r->res_lvbseq; | |
870 | rsb_clear_flag(r, RSB_VALNOTVALID); | |
871 | } | |
872 | ||
873 | if (rsb_flag(r, RSB_VALNOTVALID)) | |
874 | lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID; | |
875 | } | |
876 | ||
877 | static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
878 | { | |
879 | if (lkb->lkb_grmode < DLM_LOCK_PW) | |
880 | return; | |
881 | ||
882 | if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) { | |
883 | rsb_set_flag(r, RSB_VALNOTVALID); | |
884 | return; | |
885 | } | |
886 | ||
887 | if (!lkb->lkb_lvbptr) | |
888 | return; | |
889 | ||
890 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
891 | return; | |
892 | ||
893 | if (!r->res_lvbptr) | |
894 | r->res_lvbptr = allocate_lvb(r->res_ls); | |
895 | ||
896 | if (!r->res_lvbptr) | |
897 | return; | |
898 | ||
899 | memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); | |
900 | r->res_lvbseq++; | |
901 | rsb_clear_flag(r, RSB_VALNOTVALID); | |
902 | } | |
903 | ||
904 | /* lkb is process copy (pc) */ | |
905 | ||
906 | static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
907 | struct dlm_message *ms) | |
908 | { | |
909 | int b; | |
910 | ||
911 | if (!lkb->lkb_lvbptr) | |
912 | return; | |
913 | ||
914 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
915 | return; | |
916 | ||
917 | b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; | |
918 | if (b == 1) { | |
919 | int len = receive_extralen(ms); | |
920 | memcpy(lkb->lkb_lvbptr, ms->m_extra, len); | |
921 | lkb->lkb_lvbseq = ms->m_lvbseq; | |
922 | } | |
923 | } | |
924 | ||
925 | /* Manipulate lkb's on rsb's convert/granted/waiting queues | |
926 | remove_lock -- used for unlock, removes lkb from granted | |
927 | revert_lock -- used for cancel, moves lkb from convert to granted | |
928 | grant_lock -- used for request and convert, adds lkb to granted or | |
929 | moves lkb from convert or waiting to granted | |
930 | ||
931 | Each of these is used for master or local copy lkb's. There is | |
932 | also a _pc() variation used to make the corresponding change on | |
933 | a process copy (pc) lkb. */ | |
934 | ||
935 | static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
936 | { | |
937 | del_lkb(r, lkb); | |
938 | lkb->lkb_grmode = DLM_LOCK_IV; | |
939 | /* this unhold undoes the original ref from create_lkb() | |
940 | so this leads to the lkb being freed */ | |
941 | unhold_lkb(lkb); | |
942 | } | |
943 | ||
944 | static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
945 | { | |
946 | set_lvb_unlock(r, lkb); | |
947 | _remove_lock(r, lkb); | |
948 | } | |
949 | ||
950 | static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
951 | { | |
952 | _remove_lock(r, lkb); | |
953 | } | |
954 | ||
955 | static void revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
956 | { | |
957 | lkb->lkb_rqmode = DLM_LOCK_IV; | |
958 | ||
959 | switch (lkb->lkb_status) { | |
960 | case DLM_LKSTS_CONVERT: | |
961 | move_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
962 | break; | |
963 | case DLM_LKSTS_WAITING: | |
964 | del_lkb(r, lkb); | |
965 | lkb->lkb_grmode = DLM_LOCK_IV; | |
966 | /* this unhold undoes the original ref from create_lkb() | |
967 | so this leads to the lkb being freed */ | |
968 | unhold_lkb(lkb); | |
969 | break; | |
970 | default: | |
971 | log_print("invalid status for revert %d", lkb->lkb_status); | |
972 | } | |
973 | } | |
974 | ||
975 | static void revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
976 | { | |
977 | revert_lock(r, lkb); | |
978 | } | |
979 | ||
980 | static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
981 | { | |
982 | if (lkb->lkb_grmode != lkb->lkb_rqmode) { | |
983 | lkb->lkb_grmode = lkb->lkb_rqmode; | |
984 | if (lkb->lkb_status) | |
985 | move_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
986 | else | |
987 | add_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
988 | } | |
989 | ||
990 | lkb->lkb_rqmode = DLM_LOCK_IV; | |
991 | ||
992 | if (lkb->lkb_range) { | |
993 | lkb->lkb_range[GR_RANGE_START] = lkb->lkb_range[RQ_RANGE_START]; | |
994 | lkb->lkb_range[GR_RANGE_END] = lkb->lkb_range[RQ_RANGE_END]; | |
995 | } | |
996 | } | |
997 | ||
998 | static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
999 | { | |
1000 | set_lvb_lock(r, lkb); | |
1001 | _grant_lock(r, lkb); | |
1002 | lkb->lkb_highbast = 0; | |
1003 | } | |
1004 | ||
1005 | static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
1006 | struct dlm_message *ms) | |
1007 | { | |
1008 | set_lvb_lock_pc(r, lkb, ms); | |
1009 | _grant_lock(r, lkb); | |
1010 | } | |
1011 | ||
1012 | /* called by grant_pending_locks() which means an async grant message must | |
1013 | be sent to the requesting node in addition to granting the lock if the | |
1014 | lkb belongs to a remote node. */ | |
1015 | ||
1016 | static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1017 | { | |
1018 | grant_lock(r, lkb); | |
1019 | if (is_master_copy(lkb)) | |
1020 | send_grant(r, lkb); | |
1021 | else | |
1022 | queue_cast(r, lkb, 0); | |
1023 | } | |
1024 | ||
1025 | static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head) | |
1026 | { | |
1027 | struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb, | |
1028 | lkb_statequeue); | |
1029 | if (lkb->lkb_id == first->lkb_id) | |
90135925 | 1030 | return 1; |
e7fd4179 | 1031 | |
90135925 | 1032 | return 0; |
e7fd4179 DT |
1033 | } |
1034 | ||
1035 | /* Return 1 if the locks' ranges overlap. If the lkb has no range then it is | |
1036 | assumed to cover 0-ffffffff.ffffffff */ | |
1037 | ||
1038 | static inline int ranges_overlap(struct dlm_lkb *lkb1, struct dlm_lkb *lkb2) | |
1039 | { | |
1040 | if (!lkb1->lkb_range || !lkb2->lkb_range) | |
90135925 | 1041 | return 1; |
e7fd4179 DT |
1042 | |
1043 | if (lkb1->lkb_range[RQ_RANGE_END] < lkb2->lkb_range[GR_RANGE_START] || | |
1044 | lkb1->lkb_range[RQ_RANGE_START] > lkb2->lkb_range[GR_RANGE_END]) | |
90135925 | 1045 | return 0; |
e7fd4179 | 1046 | |
90135925 | 1047 | return 1; |
e7fd4179 DT |
1048 | } |
1049 | ||
1050 | /* Check if the given lkb conflicts with another lkb on the queue. */ | |
1051 | ||
1052 | static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb) | |
1053 | { | |
1054 | struct dlm_lkb *this; | |
1055 | ||
1056 | list_for_each_entry(this, head, lkb_statequeue) { | |
1057 | if (this == lkb) | |
1058 | continue; | |
1059 | if (ranges_overlap(lkb, this) && !modes_compat(this, lkb)) | |
90135925 | 1060 | return 1; |
e7fd4179 | 1061 | } |
90135925 | 1062 | return 0; |
e7fd4179 DT |
1063 | } |
1064 | ||
1065 | /* | |
1066 | * "A conversion deadlock arises with a pair of lock requests in the converting | |
1067 | * queue for one resource. The granted mode of each lock blocks the requested | |
1068 | * mode of the other lock." | |
1069 | * | |
1070 | * Part 2: if the granted mode of lkb is preventing the first lkb in the | |
1071 | * convert queue from being granted, then demote lkb (set grmode to NL). | |
1072 | * This second form requires that we check for conv-deadlk even when | |
1073 | * now == 0 in _can_be_granted(). | |
1074 | * | |
1075 | * Example: | |
1076 | * Granted Queue: empty | |
1077 | * Convert Queue: NL->EX (first lock) | |
1078 | * PR->EX (second lock) | |
1079 | * | |
1080 | * The first lock can't be granted because of the granted mode of the second | |
1081 | * lock and the second lock can't be granted because it's not first in the | |
1082 | * list. We demote the granted mode of the second lock (the lkb passed to this | |
1083 | * function). | |
1084 | * | |
1085 | * After the resolution, the "grant pending" function needs to go back and try | |
1086 | * to grant locks on the convert queue again since the first lock can now be | |
1087 | * granted. | |
1088 | */ | |
1089 | ||
1090 | static int conversion_deadlock_detect(struct dlm_rsb *rsb, struct dlm_lkb *lkb) | |
1091 | { | |
1092 | struct dlm_lkb *this, *first = NULL, *self = NULL; | |
1093 | ||
1094 | list_for_each_entry(this, &rsb->res_convertqueue, lkb_statequeue) { | |
1095 | if (!first) | |
1096 | first = this; | |
1097 | if (this == lkb) { | |
1098 | self = lkb; | |
1099 | continue; | |
1100 | } | |
1101 | ||
1102 | if (!ranges_overlap(lkb, this)) | |
1103 | continue; | |
1104 | ||
1105 | if (!modes_compat(this, lkb) && !modes_compat(lkb, this)) | |
90135925 | 1106 | return 1; |
e7fd4179 DT |
1107 | } |
1108 | ||
1109 | /* if lkb is on the convert queue and is preventing the first | |
1110 | from being granted, then there's deadlock and we demote lkb. | |
1111 | multiple converting locks may need to do this before the first | |
1112 | converting lock can be granted. */ | |
1113 | ||
1114 | if (self && self != first) { | |
1115 | if (!modes_compat(lkb, first) && | |
1116 | !queue_conflict(&rsb->res_grantqueue, first)) | |
90135925 | 1117 | return 1; |
e7fd4179 DT |
1118 | } |
1119 | ||
90135925 | 1120 | return 0; |
e7fd4179 DT |
1121 | } |
1122 | ||
1123 | /* | |
1124 | * Return 1 if the lock can be granted, 0 otherwise. | |
1125 | * Also detect and resolve conversion deadlocks. | |
1126 | * | |
1127 | * lkb is the lock to be granted | |
1128 | * | |
1129 | * now is 1 if the function is being called in the context of the | |
1130 | * immediate request, it is 0 if called later, after the lock has been | |
1131 | * queued. | |
1132 | * | |
1133 | * References are from chapter 6 of "VAXcluster Principles" by Roy Davis | |
1134 | */ | |
1135 | ||
1136 | static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) | |
1137 | { | |
1138 | int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV); | |
1139 | ||
1140 | /* | |
1141 | * 6-10: Version 5.4 introduced an option to address the phenomenon of | |
1142 | * a new request for a NL mode lock being blocked. | |
1143 | * | |
1144 | * 6-11: If the optional EXPEDITE flag is used with the new NL mode | |
1145 | * request, then it would be granted. In essence, the use of this flag | |
1146 | * tells the Lock Manager to expedite theis request by not considering | |
1147 | * what may be in the CONVERTING or WAITING queues... As of this | |
1148 | * writing, the EXPEDITE flag can be used only with new requests for NL | |
1149 | * mode locks. This flag is not valid for conversion requests. | |
1150 | * | |
1151 | * A shortcut. Earlier checks return an error if EXPEDITE is used in a | |
1152 | * conversion or used with a non-NL requested mode. We also know an | |
1153 | * EXPEDITE request is always granted immediately, so now must always | |
1154 | * be 1. The full condition to grant an expedite request: (now && | |
1155 | * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can | |
1156 | * therefore be shortened to just checking the flag. | |
1157 | */ | |
1158 | ||
1159 | if (lkb->lkb_exflags & DLM_LKF_EXPEDITE) | |
90135925 | 1160 | return 1; |
e7fd4179 DT |
1161 | |
1162 | /* | |
1163 | * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be | |
1164 | * added to the remaining conditions. | |
1165 | */ | |
1166 | ||
1167 | if (queue_conflict(&r->res_grantqueue, lkb)) | |
1168 | goto out; | |
1169 | ||
1170 | /* | |
1171 | * 6-3: By default, a conversion request is immediately granted if the | |
1172 | * requested mode is compatible with the modes of all other granted | |
1173 | * locks | |
1174 | */ | |
1175 | ||
1176 | if (queue_conflict(&r->res_convertqueue, lkb)) | |
1177 | goto out; | |
1178 | ||
1179 | /* | |
1180 | * 6-5: But the default algorithm for deciding whether to grant or | |
1181 | * queue conversion requests does not by itself guarantee that such | |
1182 | * requests are serviced on a "first come first serve" basis. This, in | |
1183 | * turn, can lead to a phenomenon known as "indefinate postponement". | |
1184 | * | |
1185 | * 6-7: This issue is dealt with by using the optional QUECVT flag with | |
1186 | * the system service employed to request a lock conversion. This flag | |
1187 | * forces certain conversion requests to be queued, even if they are | |
1188 | * compatible with the granted modes of other locks on the same | |
1189 | * resource. Thus, the use of this flag results in conversion requests | |
1190 | * being ordered on a "first come first servce" basis. | |
1191 | * | |
1192 | * DCT: This condition is all about new conversions being able to occur | |
1193 | * "in place" while the lock remains on the granted queue (assuming | |
1194 | * nothing else conflicts.) IOW if QUECVT isn't set, a conversion | |
1195 | * doesn't _have_ to go onto the convert queue where it's processed in | |
1196 | * order. The "now" variable is necessary to distinguish converts | |
1197 | * being received and processed for the first time now, because once a | |
1198 | * convert is moved to the conversion queue the condition below applies | |
1199 | * requiring fifo granting. | |
1200 | */ | |
1201 | ||
1202 | if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT)) | |
90135925 | 1203 | return 1; |
e7fd4179 DT |
1204 | |
1205 | /* | |
1206 | * When using range locks the NOORDER flag is set to avoid the standard | |
1207 | * vms rules on grant order. | |
1208 | */ | |
1209 | ||
1210 | if (lkb->lkb_exflags & DLM_LKF_NOORDER) | |
90135925 | 1211 | return 1; |
e7fd4179 DT |
1212 | |
1213 | /* | |
1214 | * 6-3: Once in that queue [CONVERTING], a conversion request cannot be | |
1215 | * granted until all other conversion requests ahead of it are granted | |
1216 | * and/or canceled. | |
1217 | */ | |
1218 | ||
1219 | if (!now && conv && first_in_list(lkb, &r->res_convertqueue)) | |
90135925 | 1220 | return 1; |
e7fd4179 DT |
1221 | |
1222 | /* | |
1223 | * 6-4: By default, a new request is immediately granted only if all | |
1224 | * three of the following conditions are satisfied when the request is | |
1225 | * issued: | |
1226 | * - The queue of ungranted conversion requests for the resource is | |
1227 | * empty. | |
1228 | * - The queue of ungranted new requests for the resource is empty. | |
1229 | * - The mode of the new request is compatible with the most | |
1230 | * restrictive mode of all granted locks on the resource. | |
1231 | */ | |
1232 | ||
1233 | if (now && !conv && list_empty(&r->res_convertqueue) && | |
1234 | list_empty(&r->res_waitqueue)) | |
90135925 | 1235 | return 1; |
e7fd4179 DT |
1236 | |
1237 | /* | |
1238 | * 6-4: Once a lock request is in the queue of ungranted new requests, | |
1239 | * it cannot be granted until the queue of ungranted conversion | |
1240 | * requests is empty, all ungranted new requests ahead of it are | |
1241 | * granted and/or canceled, and it is compatible with the granted mode | |
1242 | * of the most restrictive lock granted on the resource. | |
1243 | */ | |
1244 | ||
1245 | if (!now && !conv && list_empty(&r->res_convertqueue) && | |
1246 | first_in_list(lkb, &r->res_waitqueue)) | |
90135925 | 1247 | return 1; |
e7fd4179 DT |
1248 | |
1249 | out: | |
1250 | /* | |
1251 | * The following, enabled by CONVDEADLK, departs from VMS. | |
1252 | */ | |
1253 | ||
1254 | if (conv && (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) && | |
1255 | conversion_deadlock_detect(r, lkb)) { | |
1256 | lkb->lkb_grmode = DLM_LOCK_NL; | |
1257 | lkb->lkb_sbflags |= DLM_SBF_DEMOTED; | |
1258 | } | |
1259 | ||
90135925 | 1260 | return 0; |
e7fd4179 DT |
1261 | } |
1262 | ||
1263 | /* | |
1264 | * The ALTPR and ALTCW flags aren't traditional lock manager flags, but are a | |
1265 | * simple way to provide a big optimization to applications that can use them. | |
1266 | */ | |
1267 | ||
1268 | static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) | |
1269 | { | |
1270 | uint32_t flags = lkb->lkb_exflags; | |
1271 | int rv; | |
1272 | int8_t alt = 0, rqmode = lkb->lkb_rqmode; | |
1273 | ||
1274 | rv = _can_be_granted(r, lkb, now); | |
1275 | if (rv) | |
1276 | goto out; | |
1277 | ||
1278 | if (lkb->lkb_sbflags & DLM_SBF_DEMOTED) | |
1279 | goto out; | |
1280 | ||
1281 | if (rqmode != DLM_LOCK_PR && flags & DLM_LKF_ALTPR) | |
1282 | alt = DLM_LOCK_PR; | |
1283 | else if (rqmode != DLM_LOCK_CW && flags & DLM_LKF_ALTCW) | |
1284 | alt = DLM_LOCK_CW; | |
1285 | ||
1286 | if (alt) { | |
1287 | lkb->lkb_rqmode = alt; | |
1288 | rv = _can_be_granted(r, lkb, now); | |
1289 | if (rv) | |
1290 | lkb->lkb_sbflags |= DLM_SBF_ALTMODE; | |
1291 | else | |
1292 | lkb->lkb_rqmode = rqmode; | |
1293 | } | |
1294 | out: | |
1295 | return rv; | |
1296 | } | |
1297 | ||
1298 | static int grant_pending_convert(struct dlm_rsb *r, int high) | |
1299 | { | |
1300 | struct dlm_lkb *lkb, *s; | |
1301 | int hi, demoted, quit, grant_restart, demote_restart; | |
1302 | ||
1303 | quit = 0; | |
1304 | restart: | |
1305 | grant_restart = 0; | |
1306 | demote_restart = 0; | |
1307 | hi = DLM_LOCK_IV; | |
1308 | ||
1309 | list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) { | |
1310 | demoted = is_demoted(lkb); | |
90135925 | 1311 | if (can_be_granted(r, lkb, 0)) { |
e7fd4179 DT |
1312 | grant_lock_pending(r, lkb); |
1313 | grant_restart = 1; | |
1314 | } else { | |
1315 | hi = max_t(int, lkb->lkb_rqmode, hi); | |
1316 | if (!demoted && is_demoted(lkb)) | |
1317 | demote_restart = 1; | |
1318 | } | |
1319 | } | |
1320 | ||
1321 | if (grant_restart) | |
1322 | goto restart; | |
1323 | if (demote_restart && !quit) { | |
1324 | quit = 1; | |
1325 | goto restart; | |
1326 | } | |
1327 | ||
1328 | return max_t(int, high, hi); | |
1329 | } | |
1330 | ||
1331 | static int grant_pending_wait(struct dlm_rsb *r, int high) | |
1332 | { | |
1333 | struct dlm_lkb *lkb, *s; | |
1334 | ||
1335 | list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) { | |
90135925 | 1336 | if (can_be_granted(r, lkb, 0)) |
e7fd4179 DT |
1337 | grant_lock_pending(r, lkb); |
1338 | else | |
1339 | high = max_t(int, lkb->lkb_rqmode, high); | |
1340 | } | |
1341 | ||
1342 | return high; | |
1343 | } | |
1344 | ||
1345 | static void grant_pending_locks(struct dlm_rsb *r) | |
1346 | { | |
1347 | struct dlm_lkb *lkb, *s; | |
1348 | int high = DLM_LOCK_IV; | |
1349 | ||
1350 | DLM_ASSERT(is_master(r), dlm_print_rsb(r);); | |
1351 | ||
1352 | high = grant_pending_convert(r, high); | |
1353 | high = grant_pending_wait(r, high); | |
1354 | ||
1355 | if (high == DLM_LOCK_IV) | |
1356 | return; | |
1357 | ||
1358 | /* | |
1359 | * If there are locks left on the wait/convert queue then send blocking | |
1360 | * ASTs to granted locks based on the largest requested mode (high) | |
1361 | * found above. This can generate spurious blocking ASTs for range | |
1362 | * locks. FIXME: highbast < high comparison not valid for PR/CW. | |
1363 | */ | |
1364 | ||
1365 | list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) { | |
1366 | if (lkb->lkb_bastaddr && (lkb->lkb_highbast < high) && | |
1367 | !__dlm_compat_matrix[lkb->lkb_grmode+1][high+1]) { | |
1368 | queue_bast(r, lkb, high); | |
1369 | lkb->lkb_highbast = high; | |
1370 | } | |
1371 | } | |
1372 | } | |
1373 | ||
1374 | static void send_bast_queue(struct dlm_rsb *r, struct list_head *head, | |
1375 | struct dlm_lkb *lkb) | |
1376 | { | |
1377 | struct dlm_lkb *gr; | |
1378 | ||
1379 | list_for_each_entry(gr, head, lkb_statequeue) { | |
1380 | if (gr->lkb_bastaddr && | |
1381 | gr->lkb_highbast < lkb->lkb_rqmode && | |
1382 | ranges_overlap(lkb, gr) && !modes_compat(gr, lkb)) { | |
1383 | queue_bast(r, gr, lkb->lkb_rqmode); | |
1384 | gr->lkb_highbast = lkb->lkb_rqmode; | |
1385 | } | |
1386 | } | |
1387 | } | |
1388 | ||
1389 | static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1390 | { | |
1391 | send_bast_queue(r, &r->res_grantqueue, lkb); | |
1392 | } | |
1393 | ||
1394 | static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1395 | { | |
1396 | send_bast_queue(r, &r->res_grantqueue, lkb); | |
1397 | send_bast_queue(r, &r->res_convertqueue, lkb); | |
1398 | } | |
1399 | ||
1400 | /* set_master(r, lkb) -- set the master nodeid of a resource | |
1401 | ||
1402 | The purpose of this function is to set the nodeid field in the given | |
1403 | lkb using the nodeid field in the given rsb. If the rsb's nodeid is | |
1404 | known, it can just be copied to the lkb and the function will return | |
1405 | 0. If the rsb's nodeid is _not_ known, it needs to be looked up | |
1406 | before it can be copied to the lkb. | |
1407 | ||
1408 | When the rsb nodeid is being looked up remotely, the initial lkb | |
1409 | causing the lookup is kept on the ls_waiters list waiting for the | |
1410 | lookup reply. Other lkb's waiting for the same rsb lookup are kept | |
1411 | on the rsb's res_lookup list until the master is verified. | |
1412 | ||
1413 | Return values: | |
1414 | 0: nodeid is set in rsb/lkb and the caller should go ahead and use it | |
1415 | 1: the rsb master is not available and the lkb has been placed on | |
1416 | a wait queue | |
1417 | */ | |
1418 | ||
1419 | static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1420 | { | |
1421 | struct dlm_ls *ls = r->res_ls; | |
1422 | int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid(); | |
1423 | ||
1424 | if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) { | |
1425 | rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); | |
1426 | r->res_first_lkid = lkb->lkb_id; | |
1427 | lkb->lkb_nodeid = r->res_nodeid; | |
1428 | return 0; | |
1429 | } | |
1430 | ||
1431 | if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) { | |
1432 | list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup); | |
1433 | return 1; | |
1434 | } | |
1435 | ||
1436 | if (r->res_nodeid == 0) { | |
1437 | lkb->lkb_nodeid = 0; | |
1438 | return 0; | |
1439 | } | |
1440 | ||
1441 | if (r->res_nodeid > 0) { | |
1442 | lkb->lkb_nodeid = r->res_nodeid; | |
1443 | return 0; | |
1444 | } | |
1445 | ||
1446 | DLM_ASSERT(r->res_nodeid == -1, dlm_print_rsb(r);); | |
1447 | ||
1448 | dir_nodeid = dlm_dir_nodeid(r); | |
1449 | ||
1450 | if (dir_nodeid != our_nodeid) { | |
1451 | r->res_first_lkid = lkb->lkb_id; | |
1452 | send_lookup(r, lkb); | |
1453 | return 1; | |
1454 | } | |
1455 | ||
1456 | for (;;) { | |
1457 | /* It's possible for dlm_scand to remove an old rsb for | |
1458 | this same resource from the toss list, us to create | |
1459 | a new one, look up the master locally, and find it | |
1460 | already exists just before dlm_scand does the | |
1461 | dir_remove() on the previous rsb. */ | |
1462 | ||
1463 | error = dlm_dir_lookup(ls, our_nodeid, r->res_name, | |
1464 | r->res_length, &ret_nodeid); | |
1465 | if (!error) | |
1466 | break; | |
1467 | log_debug(ls, "dir_lookup error %d %s", error, r->res_name); | |
1468 | schedule(); | |
1469 | } | |
1470 | ||
1471 | if (ret_nodeid == our_nodeid) { | |
1472 | r->res_first_lkid = 0; | |
1473 | r->res_nodeid = 0; | |
1474 | lkb->lkb_nodeid = 0; | |
1475 | } else { | |
1476 | r->res_first_lkid = lkb->lkb_id; | |
1477 | r->res_nodeid = ret_nodeid; | |
1478 | lkb->lkb_nodeid = ret_nodeid; | |
1479 | } | |
1480 | return 0; | |
1481 | } | |
1482 | ||
1483 | static void process_lookup_list(struct dlm_rsb *r) | |
1484 | { | |
1485 | struct dlm_lkb *lkb, *safe; | |
1486 | ||
1487 | list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) { | |
1488 | list_del(&lkb->lkb_rsb_lookup); | |
1489 | _request_lock(r, lkb); | |
1490 | schedule(); | |
1491 | } | |
1492 | } | |
1493 | ||
1494 | /* confirm_master -- confirm (or deny) an rsb's master nodeid */ | |
1495 | ||
1496 | static void confirm_master(struct dlm_rsb *r, int error) | |
1497 | { | |
1498 | struct dlm_lkb *lkb; | |
1499 | ||
1500 | if (!r->res_first_lkid) | |
1501 | return; | |
1502 | ||
1503 | switch (error) { | |
1504 | case 0: | |
1505 | case -EINPROGRESS: | |
1506 | r->res_first_lkid = 0; | |
1507 | process_lookup_list(r); | |
1508 | break; | |
1509 | ||
1510 | case -EAGAIN: | |
1511 | /* the remote master didn't queue our NOQUEUE request; | |
1512 | make a waiting lkb the first_lkid */ | |
1513 | ||
1514 | r->res_first_lkid = 0; | |
1515 | ||
1516 | if (!list_empty(&r->res_lookup)) { | |
1517 | lkb = list_entry(r->res_lookup.next, struct dlm_lkb, | |
1518 | lkb_rsb_lookup); | |
1519 | list_del(&lkb->lkb_rsb_lookup); | |
1520 | r->res_first_lkid = lkb->lkb_id; | |
1521 | _request_lock(r, lkb); | |
1522 | } else | |
1523 | r->res_nodeid = -1; | |
1524 | break; | |
1525 | ||
1526 | default: | |
1527 | log_error(r->res_ls, "confirm_master unknown error %d", error); | |
1528 | } | |
1529 | } | |
1530 | ||
1531 | static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags, | |
1532 | int namelen, uint32_t parent_lkid, void *ast, | |
1533 | void *astarg, void *bast, struct dlm_range *range, | |
1534 | struct dlm_args *args) | |
1535 | { | |
1536 | int rv = -EINVAL; | |
1537 | ||
1538 | /* check for invalid arg usage */ | |
1539 | ||
1540 | if (mode < 0 || mode > DLM_LOCK_EX) | |
1541 | goto out; | |
1542 | ||
1543 | if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN)) | |
1544 | goto out; | |
1545 | ||
1546 | if (flags & DLM_LKF_CANCEL) | |
1547 | goto out; | |
1548 | ||
1549 | if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT)) | |
1550 | goto out; | |
1551 | ||
1552 | if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT)) | |
1553 | goto out; | |
1554 | ||
1555 | if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE) | |
1556 | goto out; | |
1557 | ||
1558 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT) | |
1559 | goto out; | |
1560 | ||
1561 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT) | |
1562 | goto out; | |
1563 | ||
1564 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE) | |
1565 | goto out; | |
1566 | ||
1567 | if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL) | |
1568 | goto out; | |
1569 | ||
1570 | if (!ast || !lksb) | |
1571 | goto out; | |
1572 | ||
1573 | if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr) | |
1574 | goto out; | |
1575 | ||
1576 | /* parent/child locks not yet supported */ | |
1577 | if (parent_lkid) | |
1578 | goto out; | |
1579 | ||
1580 | if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid) | |
1581 | goto out; | |
1582 | ||
1583 | /* these args will be copied to the lkb in validate_lock_args, | |
1584 | it cannot be done now because when converting locks, fields in | |
1585 | an active lkb cannot be modified before locking the rsb */ | |
1586 | ||
1587 | args->flags = flags; | |
1588 | args->astaddr = ast; | |
1589 | args->astparam = (long) astarg; | |
1590 | args->bastaddr = bast; | |
1591 | args->mode = mode; | |
1592 | args->lksb = lksb; | |
1593 | args->range = range; | |
1594 | rv = 0; | |
1595 | out: | |
1596 | return rv; | |
1597 | } | |
1598 | ||
1599 | static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args) | |
1600 | { | |
1601 | if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK | | |
1602 | DLM_LKF_FORCEUNLOCK)) | |
1603 | return -EINVAL; | |
1604 | ||
1605 | args->flags = flags; | |
1606 | args->astparam = (long) astarg; | |
1607 | return 0; | |
1608 | } | |
1609 | ||
1610 | static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1611 | struct dlm_args *args) | |
1612 | { | |
1613 | int rv = -EINVAL; | |
1614 | ||
1615 | if (args->flags & DLM_LKF_CONVERT) { | |
1616 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
1617 | goto out; | |
1618 | ||
1619 | if (args->flags & DLM_LKF_QUECVT && | |
1620 | !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1]) | |
1621 | goto out; | |
1622 | ||
1623 | rv = -EBUSY; | |
1624 | if (lkb->lkb_status != DLM_LKSTS_GRANTED) | |
1625 | goto out; | |
1626 | ||
1627 | if (lkb->lkb_wait_type) | |
1628 | goto out; | |
1629 | } | |
1630 | ||
1631 | lkb->lkb_exflags = args->flags; | |
1632 | lkb->lkb_sbflags = 0; | |
1633 | lkb->lkb_astaddr = args->astaddr; | |
1634 | lkb->lkb_astparam = args->astparam; | |
1635 | lkb->lkb_bastaddr = args->bastaddr; | |
1636 | lkb->lkb_rqmode = args->mode; | |
1637 | lkb->lkb_lksb = args->lksb; | |
1638 | lkb->lkb_lvbptr = args->lksb->sb_lvbptr; | |
1639 | lkb->lkb_ownpid = (int) current->pid; | |
1640 | ||
1641 | rv = 0; | |
1642 | if (!args->range) | |
1643 | goto out; | |
1644 | ||
1645 | if (!lkb->lkb_range) { | |
1646 | rv = -ENOMEM; | |
1647 | lkb->lkb_range = allocate_range(ls); | |
1648 | if (!lkb->lkb_range) | |
1649 | goto out; | |
1650 | /* This is needed for conversions that contain ranges | |
1651 | where the original lock didn't but it's harmless for | |
1652 | new locks too. */ | |
1653 | lkb->lkb_range[GR_RANGE_START] = 0LL; | |
1654 | lkb->lkb_range[GR_RANGE_END] = 0xffffffffffffffffULL; | |
1655 | } | |
1656 | ||
1657 | lkb->lkb_range[RQ_RANGE_START] = args->range->ra_start; | |
1658 | lkb->lkb_range[RQ_RANGE_END] = args->range->ra_end; | |
1659 | lkb->lkb_flags |= DLM_IFL_RANGE; | |
1660 | rv = 0; | |
1661 | out: | |
1662 | return rv; | |
1663 | } | |
1664 | ||
1665 | static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args) | |
1666 | { | |
1667 | int rv = -EINVAL; | |
1668 | ||
1669 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
1670 | goto out; | |
1671 | ||
1672 | if (args->flags & DLM_LKF_FORCEUNLOCK) | |
1673 | goto out_ok; | |
1674 | ||
1675 | if (args->flags & DLM_LKF_CANCEL && | |
1676 | lkb->lkb_status == DLM_LKSTS_GRANTED) | |
1677 | goto out; | |
1678 | ||
1679 | if (!(args->flags & DLM_LKF_CANCEL) && | |
1680 | lkb->lkb_status != DLM_LKSTS_GRANTED) | |
1681 | goto out; | |
1682 | ||
1683 | rv = -EBUSY; | |
1684 | if (lkb->lkb_wait_type) | |
1685 | goto out; | |
1686 | ||
1687 | out_ok: | |
1688 | lkb->lkb_exflags = args->flags; | |
1689 | lkb->lkb_sbflags = 0; | |
1690 | lkb->lkb_astparam = args->astparam; | |
1691 | ||
1692 | rv = 0; | |
1693 | out: | |
1694 | return rv; | |
1695 | } | |
1696 | ||
1697 | /* | |
1698 | * Four stage 4 varieties: | |
1699 | * do_request(), do_convert(), do_unlock(), do_cancel() | |
1700 | * These are called on the master node for the given lock and | |
1701 | * from the central locking logic. | |
1702 | */ | |
1703 | ||
1704 | static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1705 | { | |
1706 | int error = 0; | |
1707 | ||
90135925 | 1708 | if (can_be_granted(r, lkb, 1)) { |
e7fd4179 DT |
1709 | grant_lock(r, lkb); |
1710 | queue_cast(r, lkb, 0); | |
1711 | goto out; | |
1712 | } | |
1713 | ||
1714 | if (can_be_queued(lkb)) { | |
1715 | error = -EINPROGRESS; | |
1716 | add_lkb(r, lkb, DLM_LKSTS_WAITING); | |
1717 | send_blocking_asts(r, lkb); | |
1718 | goto out; | |
1719 | } | |
1720 | ||
1721 | error = -EAGAIN; | |
1722 | if (force_blocking_asts(lkb)) | |
1723 | send_blocking_asts_all(r, lkb); | |
1724 | queue_cast(r, lkb, -EAGAIN); | |
1725 | ||
1726 | out: | |
1727 | return error; | |
1728 | } | |
1729 | ||
1730 | static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1731 | { | |
1732 | int error = 0; | |
1733 | ||
1734 | /* changing an existing lock may allow others to be granted */ | |
1735 | ||
90135925 | 1736 | if (can_be_granted(r, lkb, 1)) { |
e7fd4179 DT |
1737 | grant_lock(r, lkb); |
1738 | queue_cast(r, lkb, 0); | |
1739 | grant_pending_locks(r); | |
1740 | goto out; | |
1741 | } | |
1742 | ||
1743 | if (can_be_queued(lkb)) { | |
1744 | if (is_demoted(lkb)) | |
1745 | grant_pending_locks(r); | |
1746 | error = -EINPROGRESS; | |
1747 | del_lkb(r, lkb); | |
1748 | add_lkb(r, lkb, DLM_LKSTS_CONVERT); | |
1749 | send_blocking_asts(r, lkb); | |
1750 | goto out; | |
1751 | } | |
1752 | ||
1753 | error = -EAGAIN; | |
1754 | if (force_blocking_asts(lkb)) | |
1755 | send_blocking_asts_all(r, lkb); | |
1756 | queue_cast(r, lkb, -EAGAIN); | |
1757 | ||
1758 | out: | |
1759 | return error; | |
1760 | } | |
1761 | ||
1762 | static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1763 | { | |
1764 | remove_lock(r, lkb); | |
1765 | queue_cast(r, lkb, -DLM_EUNLOCK); | |
1766 | grant_pending_locks(r); | |
1767 | return -DLM_EUNLOCK; | |
1768 | } | |
1769 | ||
1770 | static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1771 | { | |
1772 | revert_lock(r, lkb); | |
1773 | queue_cast(r, lkb, -DLM_ECANCEL); | |
1774 | grant_pending_locks(r); | |
1775 | return -DLM_ECANCEL; | |
1776 | } | |
1777 | ||
1778 | /* | |
1779 | * Four stage 3 varieties: | |
1780 | * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock() | |
1781 | */ | |
1782 | ||
1783 | /* add a new lkb to a possibly new rsb, called by requesting process */ | |
1784 | ||
1785 | static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1786 | { | |
1787 | int error; | |
1788 | ||
1789 | /* set_master: sets lkb nodeid from r */ | |
1790 | ||
1791 | error = set_master(r, lkb); | |
1792 | if (error < 0) | |
1793 | goto out; | |
1794 | if (error) { | |
1795 | error = 0; | |
1796 | goto out; | |
1797 | } | |
1798 | ||
1799 | if (is_remote(r)) | |
1800 | /* receive_request() calls do_request() on remote node */ | |
1801 | error = send_request(r, lkb); | |
1802 | else | |
1803 | error = do_request(r, lkb); | |
1804 | out: | |
1805 | return error; | |
1806 | } | |
1807 | ||
1808 | /* change some property of an existing lkb, e.g. mode, range */ | |
1809 | ||
1810 | static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1811 | { | |
1812 | int error; | |
1813 | ||
1814 | if (is_remote(r)) | |
1815 | /* receive_convert() calls do_convert() on remote node */ | |
1816 | error = send_convert(r, lkb); | |
1817 | else | |
1818 | error = do_convert(r, lkb); | |
1819 | ||
1820 | return error; | |
1821 | } | |
1822 | ||
1823 | /* remove an existing lkb from the granted queue */ | |
1824 | ||
1825 | static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1826 | { | |
1827 | int error; | |
1828 | ||
1829 | if (is_remote(r)) | |
1830 | /* receive_unlock() calls do_unlock() on remote node */ | |
1831 | error = send_unlock(r, lkb); | |
1832 | else | |
1833 | error = do_unlock(r, lkb); | |
1834 | ||
1835 | return error; | |
1836 | } | |
1837 | ||
1838 | /* remove an existing lkb from the convert or wait queue */ | |
1839 | ||
1840 | static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1841 | { | |
1842 | int error; | |
1843 | ||
1844 | if (is_remote(r)) | |
1845 | /* receive_cancel() calls do_cancel() on remote node */ | |
1846 | error = send_cancel(r, lkb); | |
1847 | else | |
1848 | error = do_cancel(r, lkb); | |
1849 | ||
1850 | return error; | |
1851 | } | |
1852 | ||
1853 | /* | |
1854 | * Four stage 2 varieties: | |
1855 | * request_lock(), convert_lock(), unlock_lock(), cancel_lock() | |
1856 | */ | |
1857 | ||
1858 | static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name, | |
1859 | int len, struct dlm_args *args) | |
1860 | { | |
1861 | struct dlm_rsb *r; | |
1862 | int error; | |
1863 | ||
1864 | error = validate_lock_args(ls, lkb, args); | |
1865 | if (error) | |
1866 | goto out; | |
1867 | ||
1868 | error = find_rsb(ls, name, len, R_CREATE, &r); | |
1869 | if (error) | |
1870 | goto out; | |
1871 | ||
1872 | lock_rsb(r); | |
1873 | ||
1874 | attach_lkb(r, lkb); | |
1875 | lkb->lkb_lksb->sb_lkid = lkb->lkb_id; | |
1876 | ||
1877 | error = _request_lock(r, lkb); | |
1878 | ||
1879 | unlock_rsb(r); | |
1880 | put_rsb(r); | |
1881 | ||
1882 | out: | |
1883 | return error; | |
1884 | } | |
1885 | ||
1886 | static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1887 | struct dlm_args *args) | |
1888 | { | |
1889 | struct dlm_rsb *r; | |
1890 | int error; | |
1891 | ||
1892 | r = lkb->lkb_resource; | |
1893 | ||
1894 | hold_rsb(r); | |
1895 | lock_rsb(r); | |
1896 | ||
1897 | error = validate_lock_args(ls, lkb, args); | |
1898 | if (error) | |
1899 | goto out; | |
1900 | ||
1901 | error = _convert_lock(r, lkb); | |
1902 | out: | |
1903 | unlock_rsb(r); | |
1904 | put_rsb(r); | |
1905 | return error; | |
1906 | } | |
1907 | ||
1908 | static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1909 | struct dlm_args *args) | |
1910 | { | |
1911 | struct dlm_rsb *r; | |
1912 | int error; | |
1913 | ||
1914 | r = lkb->lkb_resource; | |
1915 | ||
1916 | hold_rsb(r); | |
1917 | lock_rsb(r); | |
1918 | ||
1919 | error = validate_unlock_args(lkb, args); | |
1920 | if (error) | |
1921 | goto out; | |
1922 | ||
1923 | error = _unlock_lock(r, lkb); | |
1924 | out: | |
1925 | unlock_rsb(r); | |
1926 | put_rsb(r); | |
1927 | return error; | |
1928 | } | |
1929 | ||
1930 | static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1931 | struct dlm_args *args) | |
1932 | { | |
1933 | struct dlm_rsb *r; | |
1934 | int error; | |
1935 | ||
1936 | r = lkb->lkb_resource; | |
1937 | ||
1938 | hold_rsb(r); | |
1939 | lock_rsb(r); | |
1940 | ||
1941 | error = validate_unlock_args(lkb, args); | |
1942 | if (error) | |
1943 | goto out; | |
1944 | ||
1945 | error = _cancel_lock(r, lkb); | |
1946 | out: | |
1947 | unlock_rsb(r); | |
1948 | put_rsb(r); | |
1949 | return error; | |
1950 | } | |
1951 | ||
1952 | /* | |
1953 | * Two stage 1 varieties: dlm_lock() and dlm_unlock() | |
1954 | */ | |
1955 | ||
1956 | int dlm_lock(dlm_lockspace_t *lockspace, | |
1957 | int mode, | |
1958 | struct dlm_lksb *lksb, | |
1959 | uint32_t flags, | |
1960 | void *name, | |
1961 | unsigned int namelen, | |
1962 | uint32_t parent_lkid, | |
1963 | void (*ast) (void *astarg), | |
1964 | void *astarg, | |
1965 | void (*bast) (void *astarg, int mode), | |
1966 | struct dlm_range *range) | |
1967 | { | |
1968 | struct dlm_ls *ls; | |
1969 | struct dlm_lkb *lkb; | |
1970 | struct dlm_args args; | |
1971 | int error, convert = flags & DLM_LKF_CONVERT; | |
1972 | ||
1973 | ls = dlm_find_lockspace_local(lockspace); | |
1974 | if (!ls) | |
1975 | return -EINVAL; | |
1976 | ||
1977 | lock_recovery(ls); | |
1978 | ||
1979 | if (convert) | |
1980 | error = find_lkb(ls, lksb->sb_lkid, &lkb); | |
1981 | else | |
1982 | error = create_lkb(ls, &lkb); | |
1983 | ||
1984 | if (error) | |
1985 | goto out; | |
1986 | ||
1987 | error = set_lock_args(mode, lksb, flags, namelen, parent_lkid, ast, | |
1988 | astarg, bast, range, &args); | |
1989 | if (error) | |
1990 | goto out_put; | |
1991 | ||
1992 | if (convert) | |
1993 | error = convert_lock(ls, lkb, &args); | |
1994 | else | |
1995 | error = request_lock(ls, lkb, name, namelen, &args); | |
1996 | ||
1997 | if (error == -EINPROGRESS) | |
1998 | error = 0; | |
1999 | out_put: | |
2000 | if (convert || error) | |
2001 | put_lkb(lkb); | |
2002 | if (error == -EAGAIN) | |
2003 | error = 0; | |
2004 | out: | |
2005 | unlock_recovery(ls); | |
2006 | dlm_put_lockspace(ls); | |
2007 | return error; | |
2008 | } | |
2009 | ||
2010 | int dlm_unlock(dlm_lockspace_t *lockspace, | |
2011 | uint32_t lkid, | |
2012 | uint32_t flags, | |
2013 | struct dlm_lksb *lksb, | |
2014 | void *astarg) | |
2015 | { | |
2016 | struct dlm_ls *ls; | |
2017 | struct dlm_lkb *lkb; | |
2018 | struct dlm_args args; | |
2019 | int error; | |
2020 | ||
2021 | ls = dlm_find_lockspace_local(lockspace); | |
2022 | if (!ls) | |
2023 | return -EINVAL; | |
2024 | ||
2025 | lock_recovery(ls); | |
2026 | ||
2027 | error = find_lkb(ls, lkid, &lkb); | |
2028 | if (error) | |
2029 | goto out; | |
2030 | ||
2031 | error = set_unlock_args(flags, astarg, &args); | |
2032 | if (error) | |
2033 | goto out_put; | |
2034 | ||
2035 | if (flags & DLM_LKF_CANCEL) | |
2036 | error = cancel_lock(ls, lkb, &args); | |
2037 | else | |
2038 | error = unlock_lock(ls, lkb, &args); | |
2039 | ||
2040 | if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL) | |
2041 | error = 0; | |
2042 | out_put: | |
2043 | put_lkb(lkb); | |
2044 | out: | |
2045 | unlock_recovery(ls); | |
2046 | dlm_put_lockspace(ls); | |
2047 | return error; | |
2048 | } | |
2049 | ||
2050 | /* | |
2051 | * send/receive routines for remote operations and replies | |
2052 | * | |
2053 | * send_args | |
2054 | * send_common | |
2055 | * send_request receive_request | |
2056 | * send_convert receive_convert | |
2057 | * send_unlock receive_unlock | |
2058 | * send_cancel receive_cancel | |
2059 | * send_grant receive_grant | |
2060 | * send_bast receive_bast | |
2061 | * send_lookup receive_lookup | |
2062 | * send_remove receive_remove | |
2063 | * | |
2064 | * send_common_reply | |
2065 | * receive_request_reply send_request_reply | |
2066 | * receive_convert_reply send_convert_reply | |
2067 | * receive_unlock_reply send_unlock_reply | |
2068 | * receive_cancel_reply send_cancel_reply | |
2069 | * receive_lookup_reply send_lookup_reply | |
2070 | */ | |
2071 | ||
2072 | static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2073 | int to_nodeid, int mstype, | |
2074 | struct dlm_message **ms_ret, | |
2075 | struct dlm_mhandle **mh_ret) | |
2076 | { | |
2077 | struct dlm_message *ms; | |
2078 | struct dlm_mhandle *mh; | |
2079 | char *mb; | |
2080 | int mb_len = sizeof(struct dlm_message); | |
2081 | ||
2082 | switch (mstype) { | |
2083 | case DLM_MSG_REQUEST: | |
2084 | case DLM_MSG_LOOKUP: | |
2085 | case DLM_MSG_REMOVE: | |
2086 | mb_len += r->res_length; | |
2087 | break; | |
2088 | case DLM_MSG_CONVERT: | |
2089 | case DLM_MSG_UNLOCK: | |
2090 | case DLM_MSG_REQUEST_REPLY: | |
2091 | case DLM_MSG_CONVERT_REPLY: | |
2092 | case DLM_MSG_GRANT: | |
2093 | if (lkb && lkb->lkb_lvbptr) | |
2094 | mb_len += r->res_ls->ls_lvblen; | |
2095 | break; | |
2096 | } | |
2097 | ||
2098 | /* get_buffer gives us a message handle (mh) that we need to | |
2099 | pass into lowcomms_commit and a message buffer (mb) that we | |
2100 | write our data into */ | |
2101 | ||
2102 | mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb); | |
2103 | if (!mh) | |
2104 | return -ENOBUFS; | |
2105 | ||
2106 | memset(mb, 0, mb_len); | |
2107 | ||
2108 | ms = (struct dlm_message *) mb; | |
2109 | ||
2110 | ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); | |
2111 | ms->m_header.h_lockspace = r->res_ls->ls_global_id; | |
2112 | ms->m_header.h_nodeid = dlm_our_nodeid(); | |
2113 | ms->m_header.h_length = mb_len; | |
2114 | ms->m_header.h_cmd = DLM_MSG; | |
2115 | ||
2116 | ms->m_type = mstype; | |
2117 | ||
2118 | *mh_ret = mh; | |
2119 | *ms_ret = ms; | |
2120 | return 0; | |
2121 | } | |
2122 | ||
2123 | /* further lowcomms enhancements or alternate implementations may make | |
2124 | the return value from this function useful at some point */ | |
2125 | ||
2126 | static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms) | |
2127 | { | |
2128 | dlm_message_out(ms); | |
2129 | dlm_lowcomms_commit_buffer(mh); | |
2130 | return 0; | |
2131 | } | |
2132 | ||
2133 | static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2134 | struct dlm_message *ms) | |
2135 | { | |
2136 | ms->m_nodeid = lkb->lkb_nodeid; | |
2137 | ms->m_pid = lkb->lkb_ownpid; | |
2138 | ms->m_lkid = lkb->lkb_id; | |
2139 | ms->m_remid = lkb->lkb_remid; | |
2140 | ms->m_exflags = lkb->lkb_exflags; | |
2141 | ms->m_sbflags = lkb->lkb_sbflags; | |
2142 | ms->m_flags = lkb->lkb_flags; | |
2143 | ms->m_lvbseq = lkb->lkb_lvbseq; | |
2144 | ms->m_status = lkb->lkb_status; | |
2145 | ms->m_grmode = lkb->lkb_grmode; | |
2146 | ms->m_rqmode = lkb->lkb_rqmode; | |
2147 | ms->m_hash = r->res_hash; | |
2148 | ||
2149 | /* m_result and m_bastmode are set from function args, | |
2150 | not from lkb fields */ | |
2151 | ||
2152 | if (lkb->lkb_bastaddr) | |
2153 | ms->m_asts |= AST_BAST; | |
2154 | if (lkb->lkb_astaddr) | |
2155 | ms->m_asts |= AST_COMP; | |
2156 | ||
2157 | if (lkb->lkb_range) { | |
2158 | ms->m_range[0] = lkb->lkb_range[RQ_RANGE_START]; | |
2159 | ms->m_range[1] = lkb->lkb_range[RQ_RANGE_END]; | |
2160 | } | |
2161 | ||
2162 | if (ms->m_type == DLM_MSG_REQUEST || ms->m_type == DLM_MSG_LOOKUP) | |
2163 | memcpy(ms->m_extra, r->res_name, r->res_length); | |
2164 | ||
2165 | else if (lkb->lkb_lvbptr) | |
2166 | memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); | |
2167 | ||
2168 | } | |
2169 | ||
2170 | static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype) | |
2171 | { | |
2172 | struct dlm_message *ms; | |
2173 | struct dlm_mhandle *mh; | |
2174 | int to_nodeid, error; | |
2175 | ||
2176 | add_to_waiters(lkb, mstype); | |
2177 | ||
2178 | to_nodeid = r->res_nodeid; | |
2179 | ||
2180 | error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); | |
2181 | if (error) | |
2182 | goto fail; | |
2183 | ||
2184 | send_args(r, lkb, ms); | |
2185 | ||
2186 | error = send_message(mh, ms); | |
2187 | if (error) | |
2188 | goto fail; | |
2189 | return 0; | |
2190 | ||
2191 | fail: | |
2192 | remove_from_waiters(lkb); | |
2193 | return error; | |
2194 | } | |
2195 | ||
2196 | static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2197 | { | |
2198 | return send_common(r, lkb, DLM_MSG_REQUEST); | |
2199 | } | |
2200 | ||
2201 | static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2202 | { | |
2203 | int error; | |
2204 | ||
2205 | error = send_common(r, lkb, DLM_MSG_CONVERT); | |
2206 | ||
2207 | /* down conversions go without a reply from the master */ | |
2208 | if (!error && down_conversion(lkb)) { | |
2209 | remove_from_waiters(lkb); | |
2210 | r->res_ls->ls_stub_ms.m_result = 0; | |
2211 | __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms); | |
2212 | } | |
2213 | ||
2214 | return error; | |
2215 | } | |
2216 | ||
2217 | /* FIXME: if this lkb is the only lock we hold on the rsb, then set | |
2218 | MASTER_UNCERTAIN to force the next request on the rsb to confirm | |
2219 | that the master is still correct. */ | |
2220 | ||
2221 | static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2222 | { | |
2223 | return send_common(r, lkb, DLM_MSG_UNLOCK); | |
2224 | } | |
2225 | ||
2226 | static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2227 | { | |
2228 | return send_common(r, lkb, DLM_MSG_CANCEL); | |
2229 | } | |
2230 | ||
2231 | static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2232 | { | |
2233 | struct dlm_message *ms; | |
2234 | struct dlm_mhandle *mh; | |
2235 | int to_nodeid, error; | |
2236 | ||
2237 | to_nodeid = lkb->lkb_nodeid; | |
2238 | ||
2239 | error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh); | |
2240 | if (error) | |
2241 | goto out; | |
2242 | ||
2243 | send_args(r, lkb, ms); | |
2244 | ||
2245 | ms->m_result = 0; | |
2246 | ||
2247 | error = send_message(mh, ms); | |
2248 | out: | |
2249 | return error; | |
2250 | } | |
2251 | ||
2252 | static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode) | |
2253 | { | |
2254 | struct dlm_message *ms; | |
2255 | struct dlm_mhandle *mh; | |
2256 | int to_nodeid, error; | |
2257 | ||
2258 | to_nodeid = lkb->lkb_nodeid; | |
2259 | ||
2260 | error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh); | |
2261 | if (error) | |
2262 | goto out; | |
2263 | ||
2264 | send_args(r, lkb, ms); | |
2265 | ||
2266 | ms->m_bastmode = mode; | |
2267 | ||
2268 | error = send_message(mh, ms); | |
2269 | out: | |
2270 | return error; | |
2271 | } | |
2272 | ||
2273 | static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2274 | { | |
2275 | struct dlm_message *ms; | |
2276 | struct dlm_mhandle *mh; | |
2277 | int to_nodeid, error; | |
2278 | ||
2279 | add_to_waiters(lkb, DLM_MSG_LOOKUP); | |
2280 | ||
2281 | to_nodeid = dlm_dir_nodeid(r); | |
2282 | ||
2283 | error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh); | |
2284 | if (error) | |
2285 | goto fail; | |
2286 | ||
2287 | send_args(r, lkb, ms); | |
2288 | ||
2289 | error = send_message(mh, ms); | |
2290 | if (error) | |
2291 | goto fail; | |
2292 | return 0; | |
2293 | ||
2294 | fail: | |
2295 | remove_from_waiters(lkb); | |
2296 | return error; | |
2297 | } | |
2298 | ||
2299 | static int send_remove(struct dlm_rsb *r) | |
2300 | { | |
2301 | struct dlm_message *ms; | |
2302 | struct dlm_mhandle *mh; | |
2303 | int to_nodeid, error; | |
2304 | ||
2305 | to_nodeid = dlm_dir_nodeid(r); | |
2306 | ||
2307 | error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh); | |
2308 | if (error) | |
2309 | goto out; | |
2310 | ||
2311 | memcpy(ms->m_extra, r->res_name, r->res_length); | |
2312 | ms->m_hash = r->res_hash; | |
2313 | ||
2314 | error = send_message(mh, ms); | |
2315 | out: | |
2316 | return error; | |
2317 | } | |
2318 | ||
2319 | static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2320 | int mstype, int rv) | |
2321 | { | |
2322 | struct dlm_message *ms; | |
2323 | struct dlm_mhandle *mh; | |
2324 | int to_nodeid, error; | |
2325 | ||
2326 | to_nodeid = lkb->lkb_nodeid; | |
2327 | ||
2328 | error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); | |
2329 | if (error) | |
2330 | goto out; | |
2331 | ||
2332 | send_args(r, lkb, ms); | |
2333 | ||
2334 | ms->m_result = rv; | |
2335 | ||
2336 | error = send_message(mh, ms); | |
2337 | out: | |
2338 | return error; | |
2339 | } | |
2340 | ||
2341 | static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2342 | { | |
2343 | return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv); | |
2344 | } | |
2345 | ||
2346 | static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2347 | { | |
2348 | return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv); | |
2349 | } | |
2350 | ||
2351 | static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2352 | { | |
2353 | return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv); | |
2354 | } | |
2355 | ||
2356 | static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2357 | { | |
2358 | return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv); | |
2359 | } | |
2360 | ||
2361 | static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in, | |
2362 | int ret_nodeid, int rv) | |
2363 | { | |
2364 | struct dlm_rsb *r = &ls->ls_stub_rsb; | |
2365 | struct dlm_message *ms; | |
2366 | struct dlm_mhandle *mh; | |
2367 | int error, nodeid = ms_in->m_header.h_nodeid; | |
2368 | ||
2369 | error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh); | |
2370 | if (error) | |
2371 | goto out; | |
2372 | ||
2373 | ms->m_lkid = ms_in->m_lkid; | |
2374 | ms->m_result = rv; | |
2375 | ms->m_nodeid = ret_nodeid; | |
2376 | ||
2377 | error = send_message(mh, ms); | |
2378 | out: | |
2379 | return error; | |
2380 | } | |
2381 | ||
2382 | /* which args we save from a received message depends heavily on the type | |
2383 | of message, unlike the send side where we can safely send everything about | |
2384 | the lkb for any type of message */ | |
2385 | ||
2386 | static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2387 | { | |
2388 | lkb->lkb_exflags = ms->m_exflags; | |
2389 | lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | | |
2390 | (ms->m_flags & 0x0000FFFF); | |
2391 | } | |
2392 | ||
2393 | static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2394 | { | |
2395 | lkb->lkb_sbflags = ms->m_sbflags; | |
2396 | lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | | |
2397 | (ms->m_flags & 0x0000FFFF); | |
2398 | } | |
2399 | ||
2400 | static int receive_extralen(struct dlm_message *ms) | |
2401 | { | |
2402 | return (ms->m_header.h_length - sizeof(struct dlm_message)); | |
2403 | } | |
2404 | ||
2405 | static int receive_range(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2406 | struct dlm_message *ms) | |
2407 | { | |
2408 | if (lkb->lkb_flags & DLM_IFL_RANGE) { | |
2409 | if (!lkb->lkb_range) | |
2410 | lkb->lkb_range = allocate_range(ls); | |
2411 | if (!lkb->lkb_range) | |
2412 | return -ENOMEM; | |
2413 | lkb->lkb_range[RQ_RANGE_START] = ms->m_range[0]; | |
2414 | lkb->lkb_range[RQ_RANGE_END] = ms->m_range[1]; | |
2415 | } | |
2416 | return 0; | |
2417 | } | |
2418 | ||
2419 | static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2420 | struct dlm_message *ms) | |
2421 | { | |
2422 | int len; | |
2423 | ||
2424 | if (lkb->lkb_exflags & DLM_LKF_VALBLK) { | |
2425 | if (!lkb->lkb_lvbptr) | |
2426 | lkb->lkb_lvbptr = allocate_lvb(ls); | |
2427 | if (!lkb->lkb_lvbptr) | |
2428 | return -ENOMEM; | |
2429 | len = receive_extralen(ms); | |
2430 | memcpy(lkb->lkb_lvbptr, ms->m_extra, len); | |
2431 | } | |
2432 | return 0; | |
2433 | } | |
2434 | ||
2435 | static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2436 | struct dlm_message *ms) | |
2437 | { | |
2438 | lkb->lkb_nodeid = ms->m_header.h_nodeid; | |
2439 | lkb->lkb_ownpid = ms->m_pid; | |
2440 | lkb->lkb_remid = ms->m_lkid; | |
2441 | lkb->lkb_grmode = DLM_LOCK_IV; | |
2442 | lkb->lkb_rqmode = ms->m_rqmode; | |
2443 | lkb->lkb_bastaddr = (void *) (long) (ms->m_asts & AST_BAST); | |
2444 | lkb->lkb_astaddr = (void *) (long) (ms->m_asts & AST_COMP); | |
2445 | ||
2446 | DLM_ASSERT(is_master_copy(lkb), dlm_print_lkb(lkb);); | |
2447 | ||
2448 | if (receive_range(ls, lkb, ms)) | |
2449 | return -ENOMEM; | |
2450 | ||
2451 | if (receive_lvb(ls, lkb, ms)) | |
2452 | return -ENOMEM; | |
2453 | ||
2454 | return 0; | |
2455 | } | |
2456 | ||
2457 | static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2458 | struct dlm_message *ms) | |
2459 | { | |
2460 | if (lkb->lkb_nodeid != ms->m_header.h_nodeid) { | |
2461 | log_error(ls, "convert_args nodeid %d %d lkid %x %x", | |
2462 | lkb->lkb_nodeid, ms->m_header.h_nodeid, | |
2463 | lkb->lkb_id, lkb->lkb_remid); | |
2464 | return -EINVAL; | |
2465 | } | |
2466 | ||
2467 | if (!is_master_copy(lkb)) | |
2468 | return -EINVAL; | |
2469 | ||
2470 | if (lkb->lkb_status != DLM_LKSTS_GRANTED) | |
2471 | return -EBUSY; | |
2472 | ||
2473 | if (receive_range(ls, lkb, ms)) | |
2474 | return -ENOMEM; | |
2475 | if (lkb->lkb_range) { | |
2476 | lkb->lkb_range[GR_RANGE_START] = 0LL; | |
2477 | lkb->lkb_range[GR_RANGE_END] = 0xffffffffffffffffULL; | |
2478 | } | |
2479 | ||
2480 | if (receive_lvb(ls, lkb, ms)) | |
2481 | return -ENOMEM; | |
2482 | ||
2483 | lkb->lkb_rqmode = ms->m_rqmode; | |
2484 | lkb->lkb_lvbseq = ms->m_lvbseq; | |
2485 | ||
2486 | return 0; | |
2487 | } | |
2488 | ||
2489 | static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2490 | struct dlm_message *ms) | |
2491 | { | |
2492 | if (!is_master_copy(lkb)) | |
2493 | return -EINVAL; | |
2494 | if (receive_lvb(ls, lkb, ms)) | |
2495 | return -ENOMEM; | |
2496 | return 0; | |
2497 | } | |
2498 | ||
2499 | /* We fill in the stub-lkb fields with the info that send_xxxx_reply() | |
2500 | uses to send a reply and that the remote end uses to process the reply. */ | |
2501 | ||
2502 | static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms) | |
2503 | { | |
2504 | struct dlm_lkb *lkb = &ls->ls_stub_lkb; | |
2505 | lkb->lkb_nodeid = ms->m_header.h_nodeid; | |
2506 | lkb->lkb_remid = ms->m_lkid; | |
2507 | } | |
2508 | ||
2509 | static void receive_request(struct dlm_ls *ls, struct dlm_message *ms) | |
2510 | { | |
2511 | struct dlm_lkb *lkb; | |
2512 | struct dlm_rsb *r; | |
2513 | int error, namelen; | |
2514 | ||
2515 | error = create_lkb(ls, &lkb); | |
2516 | if (error) | |
2517 | goto fail; | |
2518 | ||
2519 | receive_flags(lkb, ms); | |
2520 | lkb->lkb_flags |= DLM_IFL_MSTCPY; | |
2521 | error = receive_request_args(ls, lkb, ms); | |
2522 | if (error) { | |
2523 | put_lkb(lkb); | |
2524 | goto fail; | |
2525 | } | |
2526 | ||
2527 | namelen = receive_extralen(ms); | |
2528 | ||
2529 | error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r); | |
2530 | if (error) { | |
2531 | put_lkb(lkb); | |
2532 | goto fail; | |
2533 | } | |
2534 | ||
2535 | lock_rsb(r); | |
2536 | ||
2537 | attach_lkb(r, lkb); | |
2538 | error = do_request(r, lkb); | |
2539 | send_request_reply(r, lkb, error); | |
2540 | ||
2541 | unlock_rsb(r); | |
2542 | put_rsb(r); | |
2543 | ||
2544 | if (error == -EINPROGRESS) | |
2545 | error = 0; | |
2546 | if (error) | |
2547 | put_lkb(lkb); | |
2548 | return; | |
2549 | ||
2550 | fail: | |
2551 | setup_stub_lkb(ls, ms); | |
2552 | send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2553 | } | |
2554 | ||
2555 | static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms) | |
2556 | { | |
2557 | struct dlm_lkb *lkb; | |
2558 | struct dlm_rsb *r; | |
90135925 | 2559 | int error, reply = 1; |
e7fd4179 DT |
2560 | |
2561 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2562 | if (error) | |
2563 | goto fail; | |
2564 | ||
2565 | r = lkb->lkb_resource; | |
2566 | ||
2567 | hold_rsb(r); | |
2568 | lock_rsb(r); | |
2569 | ||
2570 | receive_flags(lkb, ms); | |
2571 | error = receive_convert_args(ls, lkb, ms); | |
2572 | if (error) | |
2573 | goto out; | |
2574 | reply = !down_conversion(lkb); | |
2575 | ||
2576 | error = do_convert(r, lkb); | |
2577 | out: | |
2578 | if (reply) | |
2579 | send_convert_reply(r, lkb, error); | |
2580 | ||
2581 | unlock_rsb(r); | |
2582 | put_rsb(r); | |
2583 | put_lkb(lkb); | |
2584 | return; | |
2585 | ||
2586 | fail: | |
2587 | setup_stub_lkb(ls, ms); | |
2588 | send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2589 | } | |
2590 | ||
2591 | static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms) | |
2592 | { | |
2593 | struct dlm_lkb *lkb; | |
2594 | struct dlm_rsb *r; | |
2595 | int error; | |
2596 | ||
2597 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2598 | if (error) | |
2599 | goto fail; | |
2600 | ||
2601 | r = lkb->lkb_resource; | |
2602 | ||
2603 | hold_rsb(r); | |
2604 | lock_rsb(r); | |
2605 | ||
2606 | receive_flags(lkb, ms); | |
2607 | error = receive_unlock_args(ls, lkb, ms); | |
2608 | if (error) | |
2609 | goto out; | |
2610 | ||
2611 | error = do_unlock(r, lkb); | |
2612 | out: | |
2613 | send_unlock_reply(r, lkb, error); | |
2614 | ||
2615 | unlock_rsb(r); | |
2616 | put_rsb(r); | |
2617 | put_lkb(lkb); | |
2618 | return; | |
2619 | ||
2620 | fail: | |
2621 | setup_stub_lkb(ls, ms); | |
2622 | send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2623 | } | |
2624 | ||
2625 | static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms) | |
2626 | { | |
2627 | struct dlm_lkb *lkb; | |
2628 | struct dlm_rsb *r; | |
2629 | int error; | |
2630 | ||
2631 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2632 | if (error) | |
2633 | goto fail; | |
2634 | ||
2635 | receive_flags(lkb, ms); | |
2636 | ||
2637 | r = lkb->lkb_resource; | |
2638 | ||
2639 | hold_rsb(r); | |
2640 | lock_rsb(r); | |
2641 | ||
2642 | error = do_cancel(r, lkb); | |
2643 | send_cancel_reply(r, lkb, error); | |
2644 | ||
2645 | unlock_rsb(r); | |
2646 | put_rsb(r); | |
2647 | put_lkb(lkb); | |
2648 | return; | |
2649 | ||
2650 | fail: | |
2651 | setup_stub_lkb(ls, ms); | |
2652 | send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2653 | } | |
2654 | ||
2655 | static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms) | |
2656 | { | |
2657 | struct dlm_lkb *lkb; | |
2658 | struct dlm_rsb *r; | |
2659 | int error; | |
2660 | ||
2661 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2662 | if (error) { | |
2663 | log_error(ls, "receive_grant no lkb"); | |
2664 | return; | |
2665 | } | |
2666 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2667 | ||
2668 | r = lkb->lkb_resource; | |
2669 | ||
2670 | hold_rsb(r); | |
2671 | lock_rsb(r); | |
2672 | ||
2673 | receive_flags_reply(lkb, ms); | |
2674 | grant_lock_pc(r, lkb, ms); | |
2675 | queue_cast(r, lkb, 0); | |
2676 | ||
2677 | unlock_rsb(r); | |
2678 | put_rsb(r); | |
2679 | put_lkb(lkb); | |
2680 | } | |
2681 | ||
2682 | static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms) | |
2683 | { | |
2684 | struct dlm_lkb *lkb; | |
2685 | struct dlm_rsb *r; | |
2686 | int error; | |
2687 | ||
2688 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2689 | if (error) { | |
2690 | log_error(ls, "receive_bast no lkb"); | |
2691 | return; | |
2692 | } | |
2693 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2694 | ||
2695 | r = lkb->lkb_resource; | |
2696 | ||
2697 | hold_rsb(r); | |
2698 | lock_rsb(r); | |
2699 | ||
2700 | queue_bast(r, lkb, ms->m_bastmode); | |
2701 | ||
2702 | unlock_rsb(r); | |
2703 | put_rsb(r); | |
2704 | put_lkb(lkb); | |
2705 | } | |
2706 | ||
2707 | static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms) | |
2708 | { | |
2709 | int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid; | |
2710 | ||
2711 | from_nodeid = ms->m_header.h_nodeid; | |
2712 | our_nodeid = dlm_our_nodeid(); | |
2713 | ||
2714 | len = receive_extralen(ms); | |
2715 | ||
2716 | dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); | |
2717 | if (dir_nodeid != our_nodeid) { | |
2718 | log_error(ls, "lookup dir_nodeid %d from %d", | |
2719 | dir_nodeid, from_nodeid); | |
2720 | error = -EINVAL; | |
2721 | ret_nodeid = -1; | |
2722 | goto out; | |
2723 | } | |
2724 | ||
2725 | error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid); | |
2726 | ||
2727 | /* Optimization: we're master so treat lookup as a request */ | |
2728 | if (!error && ret_nodeid == our_nodeid) { | |
2729 | receive_request(ls, ms); | |
2730 | return; | |
2731 | } | |
2732 | out: | |
2733 | send_lookup_reply(ls, ms, ret_nodeid, error); | |
2734 | } | |
2735 | ||
2736 | static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms) | |
2737 | { | |
2738 | int len, dir_nodeid, from_nodeid; | |
2739 | ||
2740 | from_nodeid = ms->m_header.h_nodeid; | |
2741 | ||
2742 | len = receive_extralen(ms); | |
2743 | ||
2744 | dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); | |
2745 | if (dir_nodeid != dlm_our_nodeid()) { | |
2746 | log_error(ls, "remove dir entry dir_nodeid %d from %d", | |
2747 | dir_nodeid, from_nodeid); | |
2748 | return; | |
2749 | } | |
2750 | ||
2751 | dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len); | |
2752 | } | |
2753 | ||
2754 | static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2755 | { | |
2756 | struct dlm_lkb *lkb; | |
2757 | struct dlm_rsb *r; | |
2758 | int error, mstype; | |
2759 | ||
2760 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2761 | if (error) { | |
2762 | log_error(ls, "receive_request_reply no lkb"); | |
2763 | return; | |
2764 | } | |
2765 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2766 | ||
2767 | mstype = lkb->lkb_wait_type; | |
2768 | error = remove_from_waiters(lkb); | |
2769 | if (error) { | |
2770 | log_error(ls, "receive_request_reply not on waiters"); | |
2771 | goto out; | |
2772 | } | |
2773 | ||
2774 | /* this is the value returned from do_request() on the master */ | |
2775 | error = ms->m_result; | |
2776 | ||
2777 | r = lkb->lkb_resource; | |
2778 | hold_rsb(r); | |
2779 | lock_rsb(r); | |
2780 | ||
2781 | /* Optimization: the dir node was also the master, so it took our | |
2782 | lookup as a request and sent request reply instead of lookup reply */ | |
2783 | if (mstype == DLM_MSG_LOOKUP) { | |
2784 | r->res_nodeid = ms->m_header.h_nodeid; | |
2785 | lkb->lkb_nodeid = r->res_nodeid; | |
2786 | } | |
2787 | ||
2788 | switch (error) { | |
2789 | case -EAGAIN: | |
2790 | /* request would block (be queued) on remote master; | |
2791 | the unhold undoes the original ref from create_lkb() | |
2792 | so it leads to the lkb being freed */ | |
2793 | queue_cast(r, lkb, -EAGAIN); | |
2794 | confirm_master(r, -EAGAIN); | |
2795 | unhold_lkb(lkb); | |
2796 | break; | |
2797 | ||
2798 | case -EINPROGRESS: | |
2799 | case 0: | |
2800 | /* request was queued or granted on remote master */ | |
2801 | receive_flags_reply(lkb, ms); | |
2802 | lkb->lkb_remid = ms->m_lkid; | |
2803 | if (error) | |
2804 | add_lkb(r, lkb, DLM_LKSTS_WAITING); | |
2805 | else { | |
2806 | grant_lock_pc(r, lkb, ms); | |
2807 | queue_cast(r, lkb, 0); | |
2808 | } | |
2809 | confirm_master(r, error); | |
2810 | break; | |
2811 | ||
2812 | case -ENOENT: | |
2813 | case -ENOTBLK: | |
2814 | /* find_rsb failed to find rsb or rsb wasn't master */ | |
2815 | r->res_nodeid = -1; | |
2816 | lkb->lkb_nodeid = -1; | |
2817 | _request_lock(r, lkb); | |
2818 | break; | |
2819 | ||
2820 | default: | |
2821 | log_error(ls, "receive_request_reply error %d", error); | |
2822 | } | |
2823 | ||
2824 | unlock_rsb(r); | |
2825 | put_rsb(r); | |
2826 | out: | |
2827 | put_lkb(lkb); | |
2828 | } | |
2829 | ||
2830 | static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2831 | struct dlm_message *ms) | |
2832 | { | |
2833 | int error = ms->m_result; | |
2834 | ||
2835 | /* this is the value returned from do_convert() on the master */ | |
2836 | ||
2837 | switch (error) { | |
2838 | case -EAGAIN: | |
2839 | /* convert would block (be queued) on remote master */ | |
2840 | queue_cast(r, lkb, -EAGAIN); | |
2841 | break; | |
2842 | ||
2843 | case -EINPROGRESS: | |
2844 | /* convert was queued on remote master */ | |
2845 | del_lkb(r, lkb); | |
2846 | add_lkb(r, lkb, DLM_LKSTS_CONVERT); | |
2847 | break; | |
2848 | ||
2849 | case 0: | |
2850 | /* convert was granted on remote master */ | |
2851 | receive_flags_reply(lkb, ms); | |
2852 | grant_lock_pc(r, lkb, ms); | |
2853 | queue_cast(r, lkb, 0); | |
2854 | break; | |
2855 | ||
2856 | default: | |
2857 | log_error(r->res_ls, "receive_convert_reply error %d", error); | |
2858 | } | |
2859 | } | |
2860 | ||
2861 | static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2862 | { | |
2863 | struct dlm_rsb *r = lkb->lkb_resource; | |
2864 | ||
2865 | hold_rsb(r); | |
2866 | lock_rsb(r); | |
2867 | ||
2868 | __receive_convert_reply(r, lkb, ms); | |
2869 | ||
2870 | unlock_rsb(r); | |
2871 | put_rsb(r); | |
2872 | } | |
2873 | ||
2874 | static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2875 | { | |
2876 | struct dlm_lkb *lkb; | |
2877 | int error; | |
2878 | ||
2879 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2880 | if (error) { | |
2881 | log_error(ls, "receive_convert_reply no lkb"); | |
2882 | return; | |
2883 | } | |
2884 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2885 | ||
2886 | error = remove_from_waiters(lkb); | |
2887 | if (error) { | |
2888 | log_error(ls, "receive_convert_reply not on waiters"); | |
2889 | goto out; | |
2890 | } | |
2891 | ||
2892 | _receive_convert_reply(lkb, ms); | |
2893 | out: | |
2894 | put_lkb(lkb); | |
2895 | } | |
2896 | ||
2897 | static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2898 | { | |
2899 | struct dlm_rsb *r = lkb->lkb_resource; | |
2900 | int error = ms->m_result; | |
2901 | ||
2902 | hold_rsb(r); | |
2903 | lock_rsb(r); | |
2904 | ||
2905 | /* this is the value returned from do_unlock() on the master */ | |
2906 | ||
2907 | switch (error) { | |
2908 | case -DLM_EUNLOCK: | |
2909 | receive_flags_reply(lkb, ms); | |
2910 | remove_lock_pc(r, lkb); | |
2911 | queue_cast(r, lkb, -DLM_EUNLOCK); | |
2912 | break; | |
2913 | default: | |
2914 | log_error(r->res_ls, "receive_unlock_reply error %d", error); | |
2915 | } | |
2916 | ||
2917 | unlock_rsb(r); | |
2918 | put_rsb(r); | |
2919 | } | |
2920 | ||
2921 | static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2922 | { | |
2923 | struct dlm_lkb *lkb; | |
2924 | int error; | |
2925 | ||
2926 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2927 | if (error) { | |
2928 | log_error(ls, "receive_unlock_reply no lkb"); | |
2929 | return; | |
2930 | } | |
2931 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2932 | ||
2933 | error = remove_from_waiters(lkb); | |
2934 | if (error) { | |
2935 | log_error(ls, "receive_unlock_reply not on waiters"); | |
2936 | goto out; | |
2937 | } | |
2938 | ||
2939 | _receive_unlock_reply(lkb, ms); | |
2940 | out: | |
2941 | put_lkb(lkb); | |
2942 | } | |
2943 | ||
2944 | static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2945 | { | |
2946 | struct dlm_rsb *r = lkb->lkb_resource; | |
2947 | int error = ms->m_result; | |
2948 | ||
2949 | hold_rsb(r); | |
2950 | lock_rsb(r); | |
2951 | ||
2952 | /* this is the value returned from do_cancel() on the master */ | |
2953 | ||
2954 | switch (error) { | |
2955 | case -DLM_ECANCEL: | |
2956 | receive_flags_reply(lkb, ms); | |
2957 | revert_lock_pc(r, lkb); | |
2958 | queue_cast(r, lkb, -DLM_ECANCEL); | |
2959 | break; | |
2960 | default: | |
2961 | log_error(r->res_ls, "receive_cancel_reply error %d", error); | |
2962 | } | |
2963 | ||
2964 | unlock_rsb(r); | |
2965 | put_rsb(r); | |
2966 | } | |
2967 | ||
2968 | static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2969 | { | |
2970 | struct dlm_lkb *lkb; | |
2971 | int error; | |
2972 | ||
2973 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2974 | if (error) { | |
2975 | log_error(ls, "receive_cancel_reply no lkb"); | |
2976 | return; | |
2977 | } | |
2978 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2979 | ||
2980 | error = remove_from_waiters(lkb); | |
2981 | if (error) { | |
2982 | log_error(ls, "receive_cancel_reply not on waiters"); | |
2983 | goto out; | |
2984 | } | |
2985 | ||
2986 | _receive_cancel_reply(lkb, ms); | |
2987 | out: | |
2988 | put_lkb(lkb); | |
2989 | } | |
2990 | ||
2991 | static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2992 | { | |
2993 | struct dlm_lkb *lkb; | |
2994 | struct dlm_rsb *r; | |
2995 | int error, ret_nodeid; | |
2996 | ||
2997 | error = find_lkb(ls, ms->m_lkid, &lkb); | |
2998 | if (error) { | |
2999 | log_error(ls, "receive_lookup_reply no lkb"); | |
3000 | return; | |
3001 | } | |
3002 | ||
3003 | error = remove_from_waiters(lkb); | |
3004 | if (error) { | |
3005 | log_error(ls, "receive_lookup_reply not on waiters"); | |
3006 | goto out; | |
3007 | } | |
3008 | ||
3009 | /* this is the value returned by dlm_dir_lookup on dir node | |
3010 | FIXME: will a non-zero error ever be returned? */ | |
3011 | error = ms->m_result; | |
3012 | ||
3013 | r = lkb->lkb_resource; | |
3014 | hold_rsb(r); | |
3015 | lock_rsb(r); | |
3016 | ||
3017 | ret_nodeid = ms->m_nodeid; | |
3018 | if (ret_nodeid == dlm_our_nodeid()) { | |
3019 | r->res_nodeid = 0; | |
3020 | ret_nodeid = 0; | |
3021 | r->res_first_lkid = 0; | |
3022 | } else { | |
3023 | /* set_master() will copy res_nodeid to lkb_nodeid */ | |
3024 | r->res_nodeid = ret_nodeid; | |
3025 | } | |
3026 | ||
3027 | _request_lock(r, lkb); | |
3028 | ||
3029 | if (!ret_nodeid) | |
3030 | process_lookup_list(r); | |
3031 | ||
3032 | unlock_rsb(r); | |
3033 | put_rsb(r); | |
3034 | out: | |
3035 | put_lkb(lkb); | |
3036 | } | |
3037 | ||
3038 | int dlm_receive_message(struct dlm_header *hd, int nodeid, int recovery) | |
3039 | { | |
3040 | struct dlm_message *ms = (struct dlm_message *) hd; | |
3041 | struct dlm_ls *ls; | |
3042 | int error; | |
3043 | ||
3044 | if (!recovery) | |
3045 | dlm_message_in(ms); | |
3046 | ||
3047 | ls = dlm_find_lockspace_global(hd->h_lockspace); | |
3048 | if (!ls) { | |
3049 | log_print("drop message %d from %d for unknown lockspace %d", | |
3050 | ms->m_type, nodeid, hd->h_lockspace); | |
3051 | return -EINVAL; | |
3052 | } | |
3053 | ||
3054 | /* recovery may have just ended leaving a bunch of backed-up requests | |
3055 | in the requestqueue; wait while dlm_recoverd clears them */ | |
3056 | ||
3057 | if (!recovery) | |
3058 | dlm_wait_requestqueue(ls); | |
3059 | ||
3060 | /* recovery may have just started while there were a bunch of | |
3061 | in-flight requests -- save them in requestqueue to be processed | |
3062 | after recovery. we can't let dlm_recvd block on the recovery | |
3063 | lock. if dlm_recoverd is calling this function to clear the | |
3064 | requestqueue, it needs to be interrupted (-EINTR) if another | |
3065 | recovery operation is starting. */ | |
3066 | ||
3067 | while (1) { | |
3068 | if (dlm_locking_stopped(ls)) { | |
3069 | if (!recovery) | |
3070 | dlm_add_requestqueue(ls, nodeid, hd); | |
3071 | error = -EINTR; | |
3072 | goto out; | |
3073 | } | |
3074 | ||
3075 | if (lock_recovery_try(ls)) | |
3076 | break; | |
3077 | schedule(); | |
3078 | } | |
3079 | ||
3080 | switch (ms->m_type) { | |
3081 | ||
3082 | /* messages sent to a master node */ | |
3083 | ||
3084 | case DLM_MSG_REQUEST: | |
3085 | receive_request(ls, ms); | |
3086 | break; | |
3087 | ||
3088 | case DLM_MSG_CONVERT: | |
3089 | receive_convert(ls, ms); | |
3090 | break; | |
3091 | ||
3092 | case DLM_MSG_UNLOCK: | |
3093 | receive_unlock(ls, ms); | |
3094 | break; | |
3095 | ||
3096 | case DLM_MSG_CANCEL: | |
3097 | receive_cancel(ls, ms); | |
3098 | break; | |
3099 | ||
3100 | /* messages sent from a master node (replies to above) */ | |
3101 | ||
3102 | case DLM_MSG_REQUEST_REPLY: | |
3103 | receive_request_reply(ls, ms); | |
3104 | break; | |
3105 | ||
3106 | case DLM_MSG_CONVERT_REPLY: | |
3107 | receive_convert_reply(ls, ms); | |
3108 | break; | |
3109 | ||
3110 | case DLM_MSG_UNLOCK_REPLY: | |
3111 | receive_unlock_reply(ls, ms); | |
3112 | break; | |
3113 | ||
3114 | case DLM_MSG_CANCEL_REPLY: | |
3115 | receive_cancel_reply(ls, ms); | |
3116 | break; | |
3117 | ||
3118 | /* messages sent from a master node (only two types of async msg) */ | |
3119 | ||
3120 | case DLM_MSG_GRANT: | |
3121 | receive_grant(ls, ms); | |
3122 | break; | |
3123 | ||
3124 | case DLM_MSG_BAST: | |
3125 | receive_bast(ls, ms); | |
3126 | break; | |
3127 | ||
3128 | /* messages sent to a dir node */ | |
3129 | ||
3130 | case DLM_MSG_LOOKUP: | |
3131 | receive_lookup(ls, ms); | |
3132 | break; | |
3133 | ||
3134 | case DLM_MSG_REMOVE: | |
3135 | receive_remove(ls, ms); | |
3136 | break; | |
3137 | ||
3138 | /* messages sent from a dir node (remove has no reply) */ | |
3139 | ||
3140 | case DLM_MSG_LOOKUP_REPLY: | |
3141 | receive_lookup_reply(ls, ms); | |
3142 | break; | |
3143 | ||
3144 | default: | |
3145 | log_error(ls, "unknown message type %d", ms->m_type); | |
3146 | } | |
3147 | ||
3148 | unlock_recovery(ls); | |
3149 | out: | |
3150 | dlm_put_lockspace(ls); | |
3151 | dlm_astd_wake(); | |
3152 | return 0; | |
3153 | } | |
3154 | ||
3155 | ||
3156 | /* | |
3157 | * Recovery related | |
3158 | */ | |
3159 | ||
3160 | static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3161 | { | |
3162 | if (middle_conversion(lkb)) { | |
3163 | hold_lkb(lkb); | |
3164 | ls->ls_stub_ms.m_result = -EINPROGRESS; | |
3165 | _remove_from_waiters(lkb); | |
3166 | _receive_convert_reply(lkb, &ls->ls_stub_ms); | |
3167 | ||
3168 | /* Same special case as in receive_rcom_lock_args() */ | |
3169 | lkb->lkb_grmode = DLM_LOCK_IV; | |
3170 | rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT); | |
3171 | unhold_lkb(lkb); | |
3172 | ||
3173 | } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) { | |
3174 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3175 | } | |
3176 | ||
3177 | /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down | |
3178 | conversions are async; there's no reply from the remote master */ | |
3179 | } | |
3180 | ||
3181 | /* A waiting lkb needs recovery if the master node has failed, or | |
3182 | the master node is changing (only when no directory is used) */ | |
3183 | ||
3184 | static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3185 | { | |
3186 | if (dlm_is_removed(ls, lkb->lkb_nodeid)) | |
3187 | return 1; | |
3188 | ||
3189 | if (!dlm_no_directory(ls)) | |
3190 | return 0; | |
3191 | ||
3192 | if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid) | |
3193 | return 1; | |
3194 | ||
3195 | return 0; | |
3196 | } | |
3197 | ||
3198 | /* Recovery for locks that are waiting for replies from nodes that are now | |
3199 | gone. We can just complete unlocks and cancels by faking a reply from the | |
3200 | dead node. Requests and up-conversions we flag to be resent after | |
3201 | recovery. Down-conversions can just be completed with a fake reply like | |
3202 | unlocks. Conversions between PR and CW need special attention. */ | |
3203 | ||
3204 | void dlm_recover_waiters_pre(struct dlm_ls *ls) | |
3205 | { | |
3206 | struct dlm_lkb *lkb, *safe; | |
3207 | ||
90135925 | 3208 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3209 | |
3210 | list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) { | |
3211 | log_debug(ls, "pre recover waiter lkid %x type %d flags %x", | |
3212 | lkb->lkb_id, lkb->lkb_wait_type, lkb->lkb_flags); | |
3213 | ||
3214 | /* all outstanding lookups, regardless of destination will be | |
3215 | resent after recovery is done */ | |
3216 | ||
3217 | if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) { | |
3218 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3219 | continue; | |
3220 | } | |
3221 | ||
3222 | if (!waiter_needs_recovery(ls, lkb)) | |
3223 | continue; | |
3224 | ||
3225 | switch (lkb->lkb_wait_type) { | |
3226 | ||
3227 | case DLM_MSG_REQUEST: | |
3228 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3229 | break; | |
3230 | ||
3231 | case DLM_MSG_CONVERT: | |
3232 | recover_convert_waiter(ls, lkb); | |
3233 | break; | |
3234 | ||
3235 | case DLM_MSG_UNLOCK: | |
3236 | hold_lkb(lkb); | |
3237 | ls->ls_stub_ms.m_result = -DLM_EUNLOCK; | |
3238 | _remove_from_waiters(lkb); | |
3239 | _receive_unlock_reply(lkb, &ls->ls_stub_ms); | |
3240 | put_lkb(lkb); | |
3241 | break; | |
3242 | ||
3243 | case DLM_MSG_CANCEL: | |
3244 | hold_lkb(lkb); | |
3245 | ls->ls_stub_ms.m_result = -DLM_ECANCEL; | |
3246 | _remove_from_waiters(lkb); | |
3247 | _receive_cancel_reply(lkb, &ls->ls_stub_ms); | |
3248 | put_lkb(lkb); | |
3249 | break; | |
3250 | ||
3251 | default: | |
3252 | log_error(ls, "invalid lkb wait_type %d", | |
3253 | lkb->lkb_wait_type); | |
3254 | } | |
3255 | } | |
90135925 | 3256 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3257 | } |
3258 | ||
3259 | static int remove_resend_waiter(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) | |
3260 | { | |
3261 | struct dlm_lkb *lkb; | |
3262 | int rv = 0; | |
3263 | ||
90135925 | 3264 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3265 | list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) { |
3266 | if (lkb->lkb_flags & DLM_IFL_RESEND) { | |
3267 | rv = lkb->lkb_wait_type; | |
3268 | _remove_from_waiters(lkb); | |
3269 | lkb->lkb_flags &= ~DLM_IFL_RESEND; | |
3270 | break; | |
3271 | } | |
3272 | } | |
90135925 | 3273 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3274 | |
3275 | if (!rv) | |
3276 | lkb = NULL; | |
3277 | *lkb_ret = lkb; | |
3278 | return rv; | |
3279 | } | |
3280 | ||
3281 | /* Deal with lookups and lkb's marked RESEND from _pre. We may now be the | |
3282 | master or dir-node for r. Processing the lkb may result in it being placed | |
3283 | back on waiters. */ | |
3284 | ||
3285 | int dlm_recover_waiters_post(struct dlm_ls *ls) | |
3286 | { | |
3287 | struct dlm_lkb *lkb; | |
3288 | struct dlm_rsb *r; | |
3289 | int error = 0, mstype; | |
3290 | ||
3291 | while (1) { | |
3292 | if (dlm_locking_stopped(ls)) { | |
3293 | log_debug(ls, "recover_waiters_post aborted"); | |
3294 | error = -EINTR; | |
3295 | break; | |
3296 | } | |
3297 | ||
3298 | mstype = remove_resend_waiter(ls, &lkb); | |
3299 | if (!mstype) | |
3300 | break; | |
3301 | ||
3302 | r = lkb->lkb_resource; | |
3303 | ||
3304 | log_debug(ls, "recover_waiters_post %x type %d flags %x %s", | |
3305 | lkb->lkb_id, mstype, lkb->lkb_flags, r->res_name); | |
3306 | ||
3307 | switch (mstype) { | |
3308 | ||
3309 | case DLM_MSG_LOOKUP: | |
3310 | hold_rsb(r); | |
3311 | lock_rsb(r); | |
3312 | _request_lock(r, lkb); | |
3313 | if (is_master(r)) | |
3314 | confirm_master(r, 0); | |
3315 | unlock_rsb(r); | |
3316 | put_rsb(r); | |
3317 | break; | |
3318 | ||
3319 | case DLM_MSG_REQUEST: | |
3320 | hold_rsb(r); | |
3321 | lock_rsb(r); | |
3322 | _request_lock(r, lkb); | |
3323 | unlock_rsb(r); | |
3324 | put_rsb(r); | |
3325 | break; | |
3326 | ||
3327 | case DLM_MSG_CONVERT: | |
3328 | hold_rsb(r); | |
3329 | lock_rsb(r); | |
3330 | _convert_lock(r, lkb); | |
3331 | unlock_rsb(r); | |
3332 | put_rsb(r); | |
3333 | break; | |
3334 | ||
3335 | default: | |
3336 | log_error(ls, "recover_waiters_post type %d", mstype); | |
3337 | } | |
3338 | } | |
3339 | ||
3340 | return error; | |
3341 | } | |
3342 | ||
3343 | static void purge_queue(struct dlm_rsb *r, struct list_head *queue, | |
3344 | int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb)) | |
3345 | { | |
3346 | struct dlm_ls *ls = r->res_ls; | |
3347 | struct dlm_lkb *lkb, *safe; | |
3348 | ||
3349 | list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) { | |
3350 | if (test(ls, lkb)) { | |
3351 | del_lkb(r, lkb); | |
3352 | /* this put should free the lkb */ | |
3353 | if (!put_lkb(lkb)) | |
3354 | log_error(ls, "purged lkb not released"); | |
3355 | } | |
3356 | } | |
3357 | } | |
3358 | ||
3359 | static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3360 | { | |
3361 | return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid)); | |
3362 | } | |
3363 | ||
3364 | static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3365 | { | |
3366 | return is_master_copy(lkb); | |
3367 | } | |
3368 | ||
3369 | static void purge_dead_locks(struct dlm_rsb *r) | |
3370 | { | |
3371 | purge_queue(r, &r->res_grantqueue, &purge_dead_test); | |
3372 | purge_queue(r, &r->res_convertqueue, &purge_dead_test); | |
3373 | purge_queue(r, &r->res_waitqueue, &purge_dead_test); | |
3374 | } | |
3375 | ||
3376 | void dlm_purge_mstcpy_locks(struct dlm_rsb *r) | |
3377 | { | |
3378 | purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test); | |
3379 | purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test); | |
3380 | purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test); | |
3381 | } | |
3382 | ||
3383 | /* Get rid of locks held by nodes that are gone. */ | |
3384 | ||
3385 | int dlm_purge_locks(struct dlm_ls *ls) | |
3386 | { | |
3387 | struct dlm_rsb *r; | |
3388 | ||
3389 | log_debug(ls, "dlm_purge_locks"); | |
3390 | ||
3391 | down_write(&ls->ls_root_sem); | |
3392 | list_for_each_entry(r, &ls->ls_root_list, res_root_list) { | |
3393 | hold_rsb(r); | |
3394 | lock_rsb(r); | |
3395 | if (is_master(r)) | |
3396 | purge_dead_locks(r); | |
3397 | unlock_rsb(r); | |
3398 | unhold_rsb(r); | |
3399 | ||
3400 | schedule(); | |
3401 | } | |
3402 | up_write(&ls->ls_root_sem); | |
3403 | ||
3404 | return 0; | |
3405 | } | |
3406 | ||
3407 | int dlm_grant_after_purge(struct dlm_ls *ls) | |
3408 | { | |
3409 | struct dlm_rsb *r; | |
3410 | int i; | |
3411 | ||
3412 | for (i = 0; i < ls->ls_rsbtbl_size; i++) { | |
3413 | read_lock(&ls->ls_rsbtbl[i].lock); | |
3414 | list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) { | |
3415 | hold_rsb(r); | |
3416 | lock_rsb(r); | |
3417 | if (is_master(r)) { | |
3418 | grant_pending_locks(r); | |
3419 | confirm_master(r, 0); | |
3420 | } | |
3421 | unlock_rsb(r); | |
3422 | put_rsb(r); | |
3423 | } | |
3424 | read_unlock(&ls->ls_rsbtbl[i].lock); | |
3425 | } | |
3426 | ||
3427 | return 0; | |
3428 | } | |
3429 | ||
3430 | static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid, | |
3431 | uint32_t remid) | |
3432 | { | |
3433 | struct dlm_lkb *lkb; | |
3434 | ||
3435 | list_for_each_entry(lkb, head, lkb_statequeue) { | |
3436 | if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid) | |
3437 | return lkb; | |
3438 | } | |
3439 | return NULL; | |
3440 | } | |
3441 | ||
3442 | static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid, | |
3443 | uint32_t remid) | |
3444 | { | |
3445 | struct dlm_lkb *lkb; | |
3446 | ||
3447 | lkb = search_remid_list(&r->res_grantqueue, nodeid, remid); | |
3448 | if (lkb) | |
3449 | return lkb; | |
3450 | lkb = search_remid_list(&r->res_convertqueue, nodeid, remid); | |
3451 | if (lkb) | |
3452 | return lkb; | |
3453 | lkb = search_remid_list(&r->res_waitqueue, nodeid, remid); | |
3454 | if (lkb) | |
3455 | return lkb; | |
3456 | return NULL; | |
3457 | } | |
3458 | ||
3459 | static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
3460 | struct dlm_rsb *r, struct dlm_rcom *rc) | |
3461 | { | |
3462 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3463 | int lvblen; | |
3464 | ||
3465 | lkb->lkb_nodeid = rc->rc_header.h_nodeid; | |
3466 | lkb->lkb_ownpid = rl->rl_ownpid; | |
3467 | lkb->lkb_remid = rl->rl_lkid; | |
3468 | lkb->lkb_exflags = rl->rl_exflags; | |
3469 | lkb->lkb_flags = rl->rl_flags & 0x0000FFFF; | |
3470 | lkb->lkb_flags |= DLM_IFL_MSTCPY; | |
3471 | lkb->lkb_lvbseq = rl->rl_lvbseq; | |
3472 | lkb->lkb_rqmode = rl->rl_rqmode; | |
3473 | lkb->lkb_grmode = rl->rl_grmode; | |
3474 | /* don't set lkb_status because add_lkb wants to itself */ | |
3475 | ||
3476 | lkb->lkb_bastaddr = (void *) (long) (rl->rl_asts & AST_BAST); | |
3477 | lkb->lkb_astaddr = (void *) (long) (rl->rl_asts & AST_COMP); | |
3478 | ||
3479 | if (lkb->lkb_flags & DLM_IFL_RANGE) { | |
3480 | lkb->lkb_range = allocate_range(ls); | |
3481 | if (!lkb->lkb_range) | |
3482 | return -ENOMEM; | |
3483 | memcpy(lkb->lkb_range, rl->rl_range, 4*sizeof(uint64_t)); | |
3484 | } | |
3485 | ||
3486 | if (lkb->lkb_exflags & DLM_LKF_VALBLK) { | |
3487 | lkb->lkb_lvbptr = allocate_lvb(ls); | |
3488 | if (!lkb->lkb_lvbptr) | |
3489 | return -ENOMEM; | |
3490 | lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) - | |
3491 | sizeof(struct rcom_lock); | |
3492 | memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen); | |
3493 | } | |
3494 | ||
3495 | /* Conversions between PR and CW (middle modes) need special handling. | |
3496 | The real granted mode of these converting locks cannot be determined | |
3497 | until all locks have been rebuilt on the rsb (recover_conversion) */ | |
3498 | ||
3499 | if (rl->rl_wait_type == DLM_MSG_CONVERT && middle_conversion(lkb)) { | |
3500 | rl->rl_status = DLM_LKSTS_CONVERT; | |
3501 | lkb->lkb_grmode = DLM_LOCK_IV; | |
3502 | rsb_set_flag(r, RSB_RECOVER_CONVERT); | |
3503 | } | |
3504 | ||
3505 | return 0; | |
3506 | } | |
3507 | ||
3508 | /* This lkb may have been recovered in a previous aborted recovery so we need | |
3509 | to check if the rsb already has an lkb with the given remote nodeid/lkid. | |
3510 | If so we just send back a standard reply. If not, we create a new lkb with | |
3511 | the given values and send back our lkid. We send back our lkid by sending | |
3512 | back the rcom_lock struct we got but with the remid field filled in. */ | |
3513 | ||
3514 | int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc) | |
3515 | { | |
3516 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3517 | struct dlm_rsb *r; | |
3518 | struct dlm_lkb *lkb; | |
3519 | int error; | |
3520 | ||
3521 | if (rl->rl_parent_lkid) { | |
3522 | error = -EOPNOTSUPP; | |
3523 | goto out; | |
3524 | } | |
3525 | ||
3526 | error = find_rsb(ls, rl->rl_name, rl->rl_namelen, R_MASTER, &r); | |
3527 | if (error) | |
3528 | goto out; | |
3529 | ||
3530 | lock_rsb(r); | |
3531 | ||
3532 | lkb = search_remid(r, rc->rc_header.h_nodeid, rl->rl_lkid); | |
3533 | if (lkb) { | |
3534 | error = -EEXIST; | |
3535 | goto out_remid; | |
3536 | } | |
3537 | ||
3538 | error = create_lkb(ls, &lkb); | |
3539 | if (error) | |
3540 | goto out_unlock; | |
3541 | ||
3542 | error = receive_rcom_lock_args(ls, lkb, r, rc); | |
3543 | if (error) { | |
3544 | put_lkb(lkb); | |
3545 | goto out_unlock; | |
3546 | } | |
3547 | ||
3548 | attach_lkb(r, lkb); | |
3549 | add_lkb(r, lkb, rl->rl_status); | |
3550 | error = 0; | |
3551 | ||
3552 | out_remid: | |
3553 | /* this is the new value returned to the lock holder for | |
3554 | saving in its process-copy lkb */ | |
3555 | rl->rl_remid = lkb->lkb_id; | |
3556 | ||
3557 | out_unlock: | |
3558 | unlock_rsb(r); | |
3559 | put_rsb(r); | |
3560 | out: | |
3561 | if (error) | |
3562 | log_print("recover_master_copy %d %x", error, rl->rl_lkid); | |
3563 | rl->rl_result = error; | |
3564 | return error; | |
3565 | } | |
3566 | ||
3567 | int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc) | |
3568 | { | |
3569 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3570 | struct dlm_rsb *r; | |
3571 | struct dlm_lkb *lkb; | |
3572 | int error; | |
3573 | ||
3574 | error = find_lkb(ls, rl->rl_lkid, &lkb); | |
3575 | if (error) { | |
3576 | log_error(ls, "recover_process_copy no lkid %x", rl->rl_lkid); | |
3577 | return error; | |
3578 | } | |
3579 | ||
3580 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
3581 | ||
3582 | error = rl->rl_result; | |
3583 | ||
3584 | r = lkb->lkb_resource; | |
3585 | hold_rsb(r); | |
3586 | lock_rsb(r); | |
3587 | ||
3588 | switch (error) { | |
3589 | case -EEXIST: | |
3590 | log_debug(ls, "master copy exists %x", lkb->lkb_id); | |
3591 | /* fall through */ | |
3592 | case 0: | |
3593 | lkb->lkb_remid = rl->rl_remid; | |
3594 | break; | |
3595 | default: | |
3596 | log_error(ls, "dlm_recover_process_copy unknown error %d %x", | |
3597 | error, lkb->lkb_id); | |
3598 | } | |
3599 | ||
3600 | /* an ack for dlm_recover_locks() which waits for replies from | |
3601 | all the locks it sends to new masters */ | |
3602 | dlm_recovered_lock(r); | |
3603 | ||
3604 | unlock_rsb(r); | |
3605 | put_rsb(r); | |
3606 | put_lkb(lkb); | |
3607 | ||
3608 | return 0; | |
3609 | } | |
3610 |