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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 | */ | |
597d0cae | 58 | #include <linux/types.h> |
e7fd4179 | 59 | #include "dlm_internal.h" |
597d0cae | 60 | #include <linux/dlm_device.h> |
e7fd4179 DT |
61 | #include "memory.h" |
62 | #include "lowcomms.h" | |
63 | #include "requestqueue.h" | |
64 | #include "util.h" | |
65 | #include "dir.h" | |
66 | #include "member.h" | |
67 | #include "lockspace.h" | |
68 | #include "ast.h" | |
69 | #include "lock.h" | |
70 | #include "rcom.h" | |
71 | #include "recover.h" | |
72 | #include "lvb_table.h" | |
597d0cae | 73 | #include "user.h" |
e7fd4179 DT |
74 | #include "config.h" |
75 | ||
76 | static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
77 | static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
78 | static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
79 | static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
80 | static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
81 | static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode); | |
82 | static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
83 | static int send_remove(struct dlm_rsb *r); | |
84 | static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb); | |
85 | static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
86 | struct dlm_message *ms); | |
87 | static int receive_extralen(struct dlm_message *ms); | |
88 | ||
597d0cae DT |
89 | #define FAKE_USER_AST (void*)0xff00ff00 |
90 | ||
e7fd4179 DT |
91 | /* |
92 | * Lock compatibilty matrix - thanks Steve | |
93 | * UN = Unlocked state. Not really a state, used as a flag | |
94 | * PD = Padding. Used to make the matrix a nice power of two in size | |
95 | * Other states are the same as the VMS DLM. | |
96 | * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same) | |
97 | */ | |
98 | ||
99 | static const int __dlm_compat_matrix[8][8] = { | |
100 | /* UN NL CR CW PR PW EX PD */ | |
101 | {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */ | |
102 | {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */ | |
103 | {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */ | |
104 | {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */ | |
105 | {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */ | |
106 | {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */ | |
107 | {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */ | |
108 | {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ | |
109 | }; | |
110 | ||
111 | /* | |
112 | * This defines the direction of transfer of LVB data. | |
113 | * Granted mode is the row; requested mode is the column. | |
114 | * Usage: matrix[grmode+1][rqmode+1] | |
115 | * 1 = LVB is returned to the caller | |
116 | * 0 = LVB is written to the resource | |
117 | * -1 = nothing happens to the LVB | |
118 | */ | |
119 | ||
120 | const int dlm_lvb_operations[8][8] = { | |
121 | /* UN NL CR CW PR PW EX PD*/ | |
122 | { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */ | |
123 | { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */ | |
124 | { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */ | |
125 | { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */ | |
126 | { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */ | |
127 | { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */ | |
128 | { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */ | |
129 | { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */ | |
130 | }; | |
e7fd4179 DT |
131 | |
132 | #define modes_compat(gr, rq) \ | |
133 | __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1] | |
134 | ||
135 | int dlm_modes_compat(int mode1, int mode2) | |
136 | { | |
137 | return __dlm_compat_matrix[mode1 + 1][mode2 + 1]; | |
138 | } | |
139 | ||
140 | /* | |
141 | * Compatibility matrix for conversions with QUECVT set. | |
142 | * Granted mode is the row; requested mode is the column. | |
143 | * Usage: matrix[grmode+1][rqmode+1] | |
144 | */ | |
145 | ||
146 | static const int __quecvt_compat_matrix[8][8] = { | |
147 | /* UN NL CR CW PR PW EX PD */ | |
148 | {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */ | |
149 | {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */ | |
150 | {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */ | |
151 | {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */ | |
152 | {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */ | |
153 | {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */ | |
154 | {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */ | |
155 | {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ | |
156 | }; | |
157 | ||
597d0cae | 158 | void dlm_print_lkb(struct dlm_lkb *lkb) |
e7fd4179 DT |
159 | { |
160 | printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n" | |
161 | " status %d rqmode %d grmode %d wait_type %d ast_type %d\n", | |
162 | lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags, | |
163 | lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode, | |
164 | lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_ast_type); | |
165 | } | |
166 | ||
167 | void dlm_print_rsb(struct dlm_rsb *r) | |
168 | { | |
169 | printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n", | |
170 | r->res_nodeid, r->res_flags, r->res_first_lkid, | |
171 | r->res_recover_locks_count, r->res_name); | |
172 | } | |
173 | ||
a345da3e DT |
174 | void dlm_dump_rsb(struct dlm_rsb *r) |
175 | { | |
176 | struct dlm_lkb *lkb; | |
177 | ||
178 | dlm_print_rsb(r); | |
179 | ||
180 | printk(KERN_ERR "rsb: root_list empty %d recover_list empty %d\n", | |
181 | list_empty(&r->res_root_list), list_empty(&r->res_recover_list)); | |
182 | printk(KERN_ERR "rsb lookup list\n"); | |
183 | list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup) | |
184 | dlm_print_lkb(lkb); | |
185 | printk(KERN_ERR "rsb grant queue:\n"); | |
186 | list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) | |
187 | dlm_print_lkb(lkb); | |
188 | printk(KERN_ERR "rsb convert queue:\n"); | |
189 | list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) | |
190 | dlm_print_lkb(lkb); | |
191 | printk(KERN_ERR "rsb wait queue:\n"); | |
192 | list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) | |
193 | dlm_print_lkb(lkb); | |
194 | } | |
195 | ||
e7fd4179 DT |
196 | /* Threads cannot use the lockspace while it's being recovered */ |
197 | ||
198 | static inline void lock_recovery(struct dlm_ls *ls) | |
199 | { | |
200 | down_read(&ls->ls_in_recovery); | |
201 | } | |
202 | ||
203 | static inline void unlock_recovery(struct dlm_ls *ls) | |
204 | { | |
205 | up_read(&ls->ls_in_recovery); | |
206 | } | |
207 | ||
208 | static inline int lock_recovery_try(struct dlm_ls *ls) | |
209 | { | |
210 | return down_read_trylock(&ls->ls_in_recovery); | |
211 | } | |
212 | ||
213 | static inline int can_be_queued(struct dlm_lkb *lkb) | |
214 | { | |
215 | return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE); | |
216 | } | |
217 | ||
218 | static inline int force_blocking_asts(struct dlm_lkb *lkb) | |
219 | { | |
220 | return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST); | |
221 | } | |
222 | ||
223 | static inline int is_demoted(struct dlm_lkb *lkb) | |
224 | { | |
225 | return (lkb->lkb_sbflags & DLM_SBF_DEMOTED); | |
226 | } | |
227 | ||
228 | static inline int is_remote(struct dlm_rsb *r) | |
229 | { | |
230 | DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r);); | |
231 | return !!r->res_nodeid; | |
232 | } | |
233 | ||
234 | static inline int is_process_copy(struct dlm_lkb *lkb) | |
235 | { | |
236 | return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY)); | |
237 | } | |
238 | ||
239 | static inline int is_master_copy(struct dlm_lkb *lkb) | |
240 | { | |
241 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
242 | DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb);); | |
90135925 | 243 | return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? 1 : 0; |
e7fd4179 DT |
244 | } |
245 | ||
246 | static inline int middle_conversion(struct dlm_lkb *lkb) | |
247 | { | |
248 | if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) || | |
249 | (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW)) | |
90135925 DT |
250 | return 1; |
251 | return 0; | |
e7fd4179 DT |
252 | } |
253 | ||
254 | static inline int down_conversion(struct dlm_lkb *lkb) | |
255 | { | |
256 | return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode); | |
257 | } | |
258 | ||
259 | static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
260 | { | |
261 | if (is_master_copy(lkb)) | |
262 | return; | |
263 | ||
264 | DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb);); | |
265 | ||
266 | lkb->lkb_lksb->sb_status = rv; | |
267 | lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags; | |
268 | ||
269 | dlm_add_ast(lkb, AST_COMP); | |
270 | } | |
271 | ||
272 | static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode) | |
273 | { | |
274 | if (is_master_copy(lkb)) | |
275 | send_bast(r, lkb, rqmode); | |
276 | else { | |
277 | lkb->lkb_bastmode = rqmode; | |
278 | dlm_add_ast(lkb, AST_BAST); | |
279 | } | |
280 | } | |
281 | ||
282 | /* | |
283 | * Basic operations on rsb's and lkb's | |
284 | */ | |
285 | ||
286 | static struct dlm_rsb *create_rsb(struct dlm_ls *ls, char *name, int len) | |
287 | { | |
288 | struct dlm_rsb *r; | |
289 | ||
290 | r = allocate_rsb(ls, len); | |
291 | if (!r) | |
292 | return NULL; | |
293 | ||
294 | r->res_ls = ls; | |
295 | r->res_length = len; | |
296 | memcpy(r->res_name, name, len); | |
90135925 | 297 | mutex_init(&r->res_mutex); |
e7fd4179 DT |
298 | |
299 | INIT_LIST_HEAD(&r->res_lookup); | |
300 | INIT_LIST_HEAD(&r->res_grantqueue); | |
301 | INIT_LIST_HEAD(&r->res_convertqueue); | |
302 | INIT_LIST_HEAD(&r->res_waitqueue); | |
303 | INIT_LIST_HEAD(&r->res_root_list); | |
304 | INIT_LIST_HEAD(&r->res_recover_list); | |
305 | ||
306 | return r; | |
307 | } | |
308 | ||
309 | static int search_rsb_list(struct list_head *head, char *name, int len, | |
310 | unsigned int flags, struct dlm_rsb **r_ret) | |
311 | { | |
312 | struct dlm_rsb *r; | |
313 | int error = 0; | |
314 | ||
315 | list_for_each_entry(r, head, res_hashchain) { | |
316 | if (len == r->res_length && !memcmp(name, r->res_name, len)) | |
317 | goto found; | |
318 | } | |
597d0cae | 319 | return -EBADR; |
e7fd4179 DT |
320 | |
321 | found: | |
322 | if (r->res_nodeid && (flags & R_MASTER)) | |
323 | error = -ENOTBLK; | |
324 | *r_ret = r; | |
325 | return error; | |
326 | } | |
327 | ||
328 | static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b, | |
329 | unsigned int flags, struct dlm_rsb **r_ret) | |
330 | { | |
331 | struct dlm_rsb *r; | |
332 | int error; | |
333 | ||
334 | error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r); | |
335 | if (!error) { | |
336 | kref_get(&r->res_ref); | |
337 | goto out; | |
338 | } | |
339 | error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r); | |
340 | if (error) | |
341 | goto out; | |
342 | ||
343 | list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list); | |
344 | ||
345 | if (dlm_no_directory(ls)) | |
346 | goto out; | |
347 | ||
348 | if (r->res_nodeid == -1) { | |
349 | rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); | |
350 | r->res_first_lkid = 0; | |
351 | } else if (r->res_nodeid > 0) { | |
352 | rsb_set_flag(r, RSB_MASTER_UNCERTAIN); | |
353 | r->res_first_lkid = 0; | |
354 | } else { | |
355 | DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r);); | |
356 | DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),); | |
357 | } | |
358 | out: | |
359 | *r_ret = r; | |
360 | return error; | |
361 | } | |
362 | ||
363 | static int search_rsb(struct dlm_ls *ls, char *name, int len, int b, | |
364 | unsigned int flags, struct dlm_rsb **r_ret) | |
365 | { | |
366 | int error; | |
367 | write_lock(&ls->ls_rsbtbl[b].lock); | |
368 | error = _search_rsb(ls, name, len, b, flags, r_ret); | |
369 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
370 | return error; | |
371 | } | |
372 | ||
373 | /* | |
374 | * Find rsb in rsbtbl and potentially create/add one | |
375 | * | |
376 | * Delaying the release of rsb's has a similar benefit to applications keeping | |
377 | * NL locks on an rsb, but without the guarantee that the cached master value | |
378 | * will still be valid when the rsb is reused. Apps aren't always smart enough | |
379 | * to keep NL locks on an rsb that they may lock again shortly; this can lead | |
380 | * to excessive master lookups and removals if we don't delay the release. | |
381 | * | |
382 | * Searching for an rsb means looking through both the normal list and toss | |
383 | * list. When found on the toss list the rsb is moved to the normal list with | |
384 | * ref count of 1; when found on normal list the ref count is incremented. | |
385 | */ | |
386 | ||
387 | static int find_rsb(struct dlm_ls *ls, char *name, int namelen, | |
388 | unsigned int flags, struct dlm_rsb **r_ret) | |
389 | { | |
390 | struct dlm_rsb *r, *tmp; | |
391 | uint32_t hash, bucket; | |
392 | int error = 0; | |
393 | ||
394 | if (dlm_no_directory(ls)) | |
395 | flags |= R_CREATE; | |
396 | ||
397 | hash = jhash(name, namelen, 0); | |
398 | bucket = hash & (ls->ls_rsbtbl_size - 1); | |
399 | ||
400 | error = search_rsb(ls, name, namelen, bucket, flags, &r); | |
401 | if (!error) | |
402 | goto out; | |
403 | ||
597d0cae | 404 | if (error == -EBADR && !(flags & R_CREATE)) |
e7fd4179 DT |
405 | goto out; |
406 | ||
407 | /* the rsb was found but wasn't a master copy */ | |
408 | if (error == -ENOTBLK) | |
409 | goto out; | |
410 | ||
411 | error = -ENOMEM; | |
412 | r = create_rsb(ls, name, namelen); | |
413 | if (!r) | |
414 | goto out; | |
415 | ||
416 | r->res_hash = hash; | |
417 | r->res_bucket = bucket; | |
418 | r->res_nodeid = -1; | |
419 | kref_init(&r->res_ref); | |
420 | ||
421 | /* With no directory, the master can be set immediately */ | |
422 | if (dlm_no_directory(ls)) { | |
423 | int nodeid = dlm_dir_nodeid(r); | |
424 | if (nodeid == dlm_our_nodeid()) | |
425 | nodeid = 0; | |
426 | r->res_nodeid = nodeid; | |
427 | } | |
428 | ||
429 | write_lock(&ls->ls_rsbtbl[bucket].lock); | |
430 | error = _search_rsb(ls, name, namelen, bucket, 0, &tmp); | |
431 | if (!error) { | |
432 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
433 | free_rsb(r); | |
434 | r = tmp; | |
435 | goto out; | |
436 | } | |
437 | list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list); | |
438 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
439 | error = 0; | |
440 | out: | |
441 | *r_ret = r; | |
442 | return error; | |
443 | } | |
444 | ||
445 | int dlm_find_rsb(struct dlm_ls *ls, char *name, int namelen, | |
446 | unsigned int flags, struct dlm_rsb **r_ret) | |
447 | { | |
448 | return find_rsb(ls, name, namelen, flags, r_ret); | |
449 | } | |
450 | ||
451 | /* This is only called to add a reference when the code already holds | |
452 | a valid reference to the rsb, so there's no need for locking. */ | |
453 | ||
454 | static inline void hold_rsb(struct dlm_rsb *r) | |
455 | { | |
456 | kref_get(&r->res_ref); | |
457 | } | |
458 | ||
459 | void dlm_hold_rsb(struct dlm_rsb *r) | |
460 | { | |
461 | hold_rsb(r); | |
462 | } | |
463 | ||
464 | static void toss_rsb(struct kref *kref) | |
465 | { | |
466 | struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); | |
467 | struct dlm_ls *ls = r->res_ls; | |
468 | ||
469 | DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r);); | |
470 | kref_init(&r->res_ref); | |
471 | list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss); | |
472 | r->res_toss_time = jiffies; | |
473 | if (r->res_lvbptr) { | |
474 | free_lvb(r->res_lvbptr); | |
475 | r->res_lvbptr = NULL; | |
476 | } | |
477 | } | |
478 | ||
479 | /* When all references to the rsb are gone it's transfered to | |
480 | the tossed list for later disposal. */ | |
481 | ||
482 | static void put_rsb(struct dlm_rsb *r) | |
483 | { | |
484 | struct dlm_ls *ls = r->res_ls; | |
485 | uint32_t bucket = r->res_bucket; | |
486 | ||
487 | write_lock(&ls->ls_rsbtbl[bucket].lock); | |
488 | kref_put(&r->res_ref, toss_rsb); | |
489 | write_unlock(&ls->ls_rsbtbl[bucket].lock); | |
490 | } | |
491 | ||
492 | void dlm_put_rsb(struct dlm_rsb *r) | |
493 | { | |
494 | put_rsb(r); | |
495 | } | |
496 | ||
497 | /* See comment for unhold_lkb */ | |
498 | ||
499 | static void unhold_rsb(struct dlm_rsb *r) | |
500 | { | |
501 | int rv; | |
502 | rv = kref_put(&r->res_ref, toss_rsb); | |
a345da3e | 503 | DLM_ASSERT(!rv, dlm_dump_rsb(r);); |
e7fd4179 DT |
504 | } |
505 | ||
506 | static void kill_rsb(struct kref *kref) | |
507 | { | |
508 | struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); | |
509 | ||
510 | /* All work is done after the return from kref_put() so we | |
511 | can release the write_lock before the remove and free. */ | |
512 | ||
a345da3e DT |
513 | DLM_ASSERT(list_empty(&r->res_lookup), dlm_dump_rsb(r);); |
514 | DLM_ASSERT(list_empty(&r->res_grantqueue), dlm_dump_rsb(r);); | |
515 | DLM_ASSERT(list_empty(&r->res_convertqueue), dlm_dump_rsb(r);); | |
516 | DLM_ASSERT(list_empty(&r->res_waitqueue), dlm_dump_rsb(r);); | |
517 | DLM_ASSERT(list_empty(&r->res_root_list), dlm_dump_rsb(r);); | |
518 | DLM_ASSERT(list_empty(&r->res_recover_list), dlm_dump_rsb(r);); | |
e7fd4179 DT |
519 | } |
520 | ||
521 | /* Attaching/detaching lkb's from rsb's is for rsb reference counting. | |
522 | The rsb must exist as long as any lkb's for it do. */ | |
523 | ||
524 | static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
525 | { | |
526 | hold_rsb(r); | |
527 | lkb->lkb_resource = r; | |
528 | } | |
529 | ||
530 | static void detach_lkb(struct dlm_lkb *lkb) | |
531 | { | |
532 | if (lkb->lkb_resource) { | |
533 | put_rsb(lkb->lkb_resource); | |
534 | lkb->lkb_resource = NULL; | |
535 | } | |
536 | } | |
537 | ||
538 | static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) | |
539 | { | |
540 | struct dlm_lkb *lkb, *tmp; | |
541 | uint32_t lkid = 0; | |
542 | uint16_t bucket; | |
543 | ||
544 | lkb = allocate_lkb(ls); | |
545 | if (!lkb) | |
546 | return -ENOMEM; | |
547 | ||
548 | lkb->lkb_nodeid = -1; | |
549 | lkb->lkb_grmode = DLM_LOCK_IV; | |
550 | kref_init(&lkb->lkb_ref); | |
34e22bed | 551 | INIT_LIST_HEAD(&lkb->lkb_ownqueue); |
e7fd4179 DT |
552 | |
553 | get_random_bytes(&bucket, sizeof(bucket)); | |
554 | bucket &= (ls->ls_lkbtbl_size - 1); | |
555 | ||
556 | write_lock(&ls->ls_lkbtbl[bucket].lock); | |
557 | ||
558 | /* counter can roll over so we must verify lkid is not in use */ | |
559 | ||
560 | while (lkid == 0) { | |
561 | lkid = bucket | (ls->ls_lkbtbl[bucket].counter++ << 16); | |
562 | ||
563 | list_for_each_entry(tmp, &ls->ls_lkbtbl[bucket].list, | |
564 | lkb_idtbl_list) { | |
565 | if (tmp->lkb_id != lkid) | |
566 | continue; | |
567 | lkid = 0; | |
568 | break; | |
569 | } | |
570 | } | |
571 | ||
572 | lkb->lkb_id = lkid; | |
573 | list_add(&lkb->lkb_idtbl_list, &ls->ls_lkbtbl[bucket].list); | |
574 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
575 | ||
576 | *lkb_ret = lkb; | |
577 | return 0; | |
578 | } | |
579 | ||
580 | static struct dlm_lkb *__find_lkb(struct dlm_ls *ls, uint32_t lkid) | |
581 | { | |
582 | uint16_t bucket = lkid & 0xFFFF; | |
583 | struct dlm_lkb *lkb; | |
584 | ||
585 | list_for_each_entry(lkb, &ls->ls_lkbtbl[bucket].list, lkb_idtbl_list) { | |
586 | if (lkb->lkb_id == lkid) | |
587 | return lkb; | |
588 | } | |
589 | return NULL; | |
590 | } | |
591 | ||
592 | static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret) | |
593 | { | |
594 | struct dlm_lkb *lkb; | |
595 | uint16_t bucket = lkid & 0xFFFF; | |
596 | ||
597 | if (bucket >= ls->ls_lkbtbl_size) | |
598 | return -EBADSLT; | |
599 | ||
600 | read_lock(&ls->ls_lkbtbl[bucket].lock); | |
601 | lkb = __find_lkb(ls, lkid); | |
602 | if (lkb) | |
603 | kref_get(&lkb->lkb_ref); | |
604 | read_unlock(&ls->ls_lkbtbl[bucket].lock); | |
605 | ||
606 | *lkb_ret = lkb; | |
607 | return lkb ? 0 : -ENOENT; | |
608 | } | |
609 | ||
610 | static void kill_lkb(struct kref *kref) | |
611 | { | |
612 | struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref); | |
613 | ||
614 | /* All work is done after the return from kref_put() so we | |
615 | can release the write_lock before the detach_lkb */ | |
616 | ||
617 | DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); | |
618 | } | |
619 | ||
b3f58d8f DT |
620 | /* __put_lkb() is used when an lkb may not have an rsb attached to |
621 | it so we need to provide the lockspace explicitly */ | |
622 | ||
623 | static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
e7fd4179 | 624 | { |
e7fd4179 DT |
625 | uint16_t bucket = lkb->lkb_id & 0xFFFF; |
626 | ||
627 | write_lock(&ls->ls_lkbtbl[bucket].lock); | |
628 | if (kref_put(&lkb->lkb_ref, kill_lkb)) { | |
629 | list_del(&lkb->lkb_idtbl_list); | |
630 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
631 | ||
632 | detach_lkb(lkb); | |
633 | ||
634 | /* for local/process lkbs, lvbptr points to caller's lksb */ | |
635 | if (lkb->lkb_lvbptr && is_master_copy(lkb)) | |
636 | free_lvb(lkb->lkb_lvbptr); | |
e7fd4179 DT |
637 | free_lkb(lkb); |
638 | return 1; | |
639 | } else { | |
640 | write_unlock(&ls->ls_lkbtbl[bucket].lock); | |
641 | return 0; | |
642 | } | |
643 | } | |
644 | ||
645 | int dlm_put_lkb(struct dlm_lkb *lkb) | |
646 | { | |
b3f58d8f DT |
647 | struct dlm_ls *ls; |
648 | ||
649 | DLM_ASSERT(lkb->lkb_resource, dlm_print_lkb(lkb);); | |
650 | DLM_ASSERT(lkb->lkb_resource->res_ls, dlm_print_lkb(lkb);); | |
651 | ||
652 | ls = lkb->lkb_resource->res_ls; | |
653 | return __put_lkb(ls, lkb); | |
e7fd4179 DT |
654 | } |
655 | ||
656 | /* This is only called to add a reference when the code already holds | |
657 | a valid reference to the lkb, so there's no need for locking. */ | |
658 | ||
659 | static inline void hold_lkb(struct dlm_lkb *lkb) | |
660 | { | |
661 | kref_get(&lkb->lkb_ref); | |
662 | } | |
663 | ||
664 | /* This is called when we need to remove a reference and are certain | |
665 | it's not the last ref. e.g. del_lkb is always called between a | |
666 | find_lkb/put_lkb and is always the inverse of a previous add_lkb. | |
667 | put_lkb would work fine, but would involve unnecessary locking */ | |
668 | ||
669 | static inline void unhold_lkb(struct dlm_lkb *lkb) | |
670 | { | |
671 | int rv; | |
672 | rv = kref_put(&lkb->lkb_ref, kill_lkb); | |
673 | DLM_ASSERT(!rv, dlm_print_lkb(lkb);); | |
674 | } | |
675 | ||
676 | static void lkb_add_ordered(struct list_head *new, struct list_head *head, | |
677 | int mode) | |
678 | { | |
679 | struct dlm_lkb *lkb = NULL; | |
680 | ||
681 | list_for_each_entry(lkb, head, lkb_statequeue) | |
682 | if (lkb->lkb_rqmode < mode) | |
683 | break; | |
684 | ||
685 | if (!lkb) | |
686 | list_add_tail(new, head); | |
687 | else | |
688 | __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue); | |
689 | } | |
690 | ||
691 | /* add/remove lkb to rsb's grant/convert/wait queue */ | |
692 | ||
693 | static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status) | |
694 | { | |
695 | kref_get(&lkb->lkb_ref); | |
696 | ||
697 | DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); | |
698 | ||
699 | lkb->lkb_status = status; | |
700 | ||
701 | switch (status) { | |
702 | case DLM_LKSTS_WAITING: | |
703 | if (lkb->lkb_exflags & DLM_LKF_HEADQUE) | |
704 | list_add(&lkb->lkb_statequeue, &r->res_waitqueue); | |
705 | else | |
706 | list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue); | |
707 | break; | |
708 | case DLM_LKSTS_GRANTED: | |
709 | /* convention says granted locks kept in order of grmode */ | |
710 | lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue, | |
711 | lkb->lkb_grmode); | |
712 | break; | |
713 | case DLM_LKSTS_CONVERT: | |
714 | if (lkb->lkb_exflags & DLM_LKF_HEADQUE) | |
715 | list_add(&lkb->lkb_statequeue, &r->res_convertqueue); | |
716 | else | |
717 | list_add_tail(&lkb->lkb_statequeue, | |
718 | &r->res_convertqueue); | |
719 | break; | |
720 | default: | |
721 | DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status);); | |
722 | } | |
723 | } | |
724 | ||
725 | static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
726 | { | |
727 | lkb->lkb_status = 0; | |
728 | list_del(&lkb->lkb_statequeue); | |
729 | unhold_lkb(lkb); | |
730 | } | |
731 | ||
732 | static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts) | |
733 | { | |
734 | hold_lkb(lkb); | |
735 | del_lkb(r, lkb); | |
736 | add_lkb(r, lkb, sts); | |
737 | unhold_lkb(lkb); | |
738 | } | |
739 | ||
740 | /* add/remove lkb from global waiters list of lkb's waiting for | |
741 | a reply from a remote node */ | |
742 | ||
743 | static void add_to_waiters(struct dlm_lkb *lkb, int mstype) | |
744 | { | |
745 | struct dlm_ls *ls = lkb->lkb_resource->res_ls; | |
746 | ||
90135925 | 747 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
748 | if (lkb->lkb_wait_type) { |
749 | log_print("add_to_waiters error %d", lkb->lkb_wait_type); | |
750 | goto out; | |
751 | } | |
752 | lkb->lkb_wait_type = mstype; | |
753 | kref_get(&lkb->lkb_ref); | |
754 | list_add(&lkb->lkb_wait_reply, &ls->ls_waiters); | |
755 | out: | |
90135925 | 756 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
757 | } |
758 | ||
759 | static int _remove_from_waiters(struct dlm_lkb *lkb) | |
760 | { | |
761 | int error = 0; | |
762 | ||
763 | if (!lkb->lkb_wait_type) { | |
764 | log_print("remove_from_waiters error"); | |
765 | error = -EINVAL; | |
766 | goto out; | |
767 | } | |
768 | lkb->lkb_wait_type = 0; | |
769 | list_del(&lkb->lkb_wait_reply); | |
770 | unhold_lkb(lkb); | |
771 | out: | |
772 | return error; | |
773 | } | |
774 | ||
775 | static int remove_from_waiters(struct dlm_lkb *lkb) | |
776 | { | |
777 | struct dlm_ls *ls = lkb->lkb_resource->res_ls; | |
778 | int error; | |
779 | ||
90135925 | 780 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 | 781 | error = _remove_from_waiters(lkb); |
90135925 | 782 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
783 | return error; |
784 | } | |
785 | ||
786 | static void dir_remove(struct dlm_rsb *r) | |
787 | { | |
788 | int to_nodeid; | |
789 | ||
790 | if (dlm_no_directory(r->res_ls)) | |
791 | return; | |
792 | ||
793 | to_nodeid = dlm_dir_nodeid(r); | |
794 | if (to_nodeid != dlm_our_nodeid()) | |
795 | send_remove(r); | |
796 | else | |
797 | dlm_dir_remove_entry(r->res_ls, to_nodeid, | |
798 | r->res_name, r->res_length); | |
799 | } | |
800 | ||
801 | /* FIXME: shouldn't this be able to exit as soon as one non-due rsb is | |
802 | found since they are in order of newest to oldest? */ | |
803 | ||
804 | static int shrink_bucket(struct dlm_ls *ls, int b) | |
805 | { | |
806 | struct dlm_rsb *r; | |
807 | int count = 0, found; | |
808 | ||
809 | for (;;) { | |
90135925 | 810 | found = 0; |
e7fd4179 DT |
811 | write_lock(&ls->ls_rsbtbl[b].lock); |
812 | list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss, | |
813 | res_hashchain) { | |
814 | if (!time_after_eq(jiffies, r->res_toss_time + | |
815 | dlm_config.toss_secs * HZ)) | |
816 | continue; | |
90135925 | 817 | found = 1; |
e7fd4179 DT |
818 | break; |
819 | } | |
820 | ||
821 | if (!found) { | |
822 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
823 | break; | |
824 | } | |
825 | ||
826 | if (kref_put(&r->res_ref, kill_rsb)) { | |
827 | list_del(&r->res_hashchain); | |
828 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
829 | ||
830 | if (is_master(r)) | |
831 | dir_remove(r); | |
832 | free_rsb(r); | |
833 | count++; | |
834 | } else { | |
835 | write_unlock(&ls->ls_rsbtbl[b].lock); | |
836 | log_error(ls, "tossed rsb in use %s", r->res_name); | |
837 | } | |
838 | } | |
839 | ||
840 | return count; | |
841 | } | |
842 | ||
843 | void dlm_scan_rsbs(struct dlm_ls *ls) | |
844 | { | |
845 | int i; | |
846 | ||
847 | if (dlm_locking_stopped(ls)) | |
848 | return; | |
849 | ||
850 | for (i = 0; i < ls->ls_rsbtbl_size; i++) { | |
851 | shrink_bucket(ls, i); | |
852 | cond_resched(); | |
853 | } | |
854 | } | |
855 | ||
856 | /* lkb is master or local copy */ | |
857 | ||
858 | static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
859 | { | |
860 | int b, len = r->res_ls->ls_lvblen; | |
861 | ||
862 | /* b=1 lvb returned to caller | |
863 | b=0 lvb written to rsb or invalidated | |
864 | b=-1 do nothing */ | |
865 | ||
866 | b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; | |
867 | ||
868 | if (b == 1) { | |
869 | if (!lkb->lkb_lvbptr) | |
870 | return; | |
871 | ||
872 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
873 | return; | |
874 | ||
875 | if (!r->res_lvbptr) | |
876 | return; | |
877 | ||
878 | memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len); | |
879 | lkb->lkb_lvbseq = r->res_lvbseq; | |
880 | ||
881 | } else if (b == 0) { | |
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, len); | |
900 | r->res_lvbseq++; | |
901 | lkb->lkb_lvbseq = r->res_lvbseq; | |
902 | rsb_clear_flag(r, RSB_VALNOTVALID); | |
903 | } | |
904 | ||
905 | if (rsb_flag(r, RSB_VALNOTVALID)) | |
906 | lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID; | |
907 | } | |
908 | ||
909 | static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
910 | { | |
911 | if (lkb->lkb_grmode < DLM_LOCK_PW) | |
912 | return; | |
913 | ||
914 | if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) { | |
915 | rsb_set_flag(r, RSB_VALNOTVALID); | |
916 | return; | |
917 | } | |
918 | ||
919 | if (!lkb->lkb_lvbptr) | |
920 | return; | |
921 | ||
922 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
923 | return; | |
924 | ||
925 | if (!r->res_lvbptr) | |
926 | r->res_lvbptr = allocate_lvb(r->res_ls); | |
927 | ||
928 | if (!r->res_lvbptr) | |
929 | return; | |
930 | ||
931 | memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); | |
932 | r->res_lvbseq++; | |
933 | rsb_clear_flag(r, RSB_VALNOTVALID); | |
934 | } | |
935 | ||
936 | /* lkb is process copy (pc) */ | |
937 | ||
938 | static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
939 | struct dlm_message *ms) | |
940 | { | |
941 | int b; | |
942 | ||
943 | if (!lkb->lkb_lvbptr) | |
944 | return; | |
945 | ||
946 | if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) | |
947 | return; | |
948 | ||
597d0cae | 949 | b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; |
e7fd4179 DT |
950 | if (b == 1) { |
951 | int len = receive_extralen(ms); | |
952 | memcpy(lkb->lkb_lvbptr, ms->m_extra, len); | |
953 | lkb->lkb_lvbseq = ms->m_lvbseq; | |
954 | } | |
955 | } | |
956 | ||
957 | /* Manipulate lkb's on rsb's convert/granted/waiting queues | |
958 | remove_lock -- used for unlock, removes lkb from granted | |
959 | revert_lock -- used for cancel, moves lkb from convert to granted | |
960 | grant_lock -- used for request and convert, adds lkb to granted or | |
961 | moves lkb from convert or waiting to granted | |
962 | ||
963 | Each of these is used for master or local copy lkb's. There is | |
964 | also a _pc() variation used to make the corresponding change on | |
965 | a process copy (pc) lkb. */ | |
966 | ||
967 | static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
968 | { | |
969 | del_lkb(r, lkb); | |
970 | lkb->lkb_grmode = DLM_LOCK_IV; | |
971 | /* this unhold undoes the original ref from create_lkb() | |
972 | so this leads to the lkb being freed */ | |
973 | unhold_lkb(lkb); | |
974 | } | |
975 | ||
976 | static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
977 | { | |
978 | set_lvb_unlock(r, lkb); | |
979 | _remove_lock(r, lkb); | |
980 | } | |
981 | ||
982 | static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
983 | { | |
984 | _remove_lock(r, lkb); | |
985 | } | |
986 | ||
987 | static void revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
988 | { | |
989 | lkb->lkb_rqmode = DLM_LOCK_IV; | |
990 | ||
991 | switch (lkb->lkb_status) { | |
597d0cae DT |
992 | case DLM_LKSTS_GRANTED: |
993 | break; | |
e7fd4179 DT |
994 | case DLM_LKSTS_CONVERT: |
995 | move_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
996 | break; | |
997 | case DLM_LKSTS_WAITING: | |
998 | del_lkb(r, lkb); | |
999 | lkb->lkb_grmode = DLM_LOCK_IV; | |
1000 | /* this unhold undoes the original ref from create_lkb() | |
1001 | so this leads to the lkb being freed */ | |
1002 | unhold_lkb(lkb); | |
1003 | break; | |
1004 | default: | |
1005 | log_print("invalid status for revert %d", lkb->lkb_status); | |
1006 | } | |
1007 | } | |
1008 | ||
1009 | static void revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1010 | { | |
1011 | revert_lock(r, lkb); | |
1012 | } | |
1013 | ||
1014 | static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1015 | { | |
1016 | if (lkb->lkb_grmode != lkb->lkb_rqmode) { | |
1017 | lkb->lkb_grmode = lkb->lkb_rqmode; | |
1018 | if (lkb->lkb_status) | |
1019 | move_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
1020 | else | |
1021 | add_lkb(r, lkb, DLM_LKSTS_GRANTED); | |
1022 | } | |
1023 | ||
1024 | lkb->lkb_rqmode = DLM_LOCK_IV; | |
e7fd4179 DT |
1025 | } |
1026 | ||
1027 | static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1028 | { | |
1029 | set_lvb_lock(r, lkb); | |
1030 | _grant_lock(r, lkb); | |
1031 | lkb->lkb_highbast = 0; | |
1032 | } | |
1033 | ||
1034 | static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
1035 | struct dlm_message *ms) | |
1036 | { | |
1037 | set_lvb_lock_pc(r, lkb, ms); | |
1038 | _grant_lock(r, lkb); | |
1039 | } | |
1040 | ||
1041 | /* called by grant_pending_locks() which means an async grant message must | |
1042 | be sent to the requesting node in addition to granting the lock if the | |
1043 | lkb belongs to a remote node. */ | |
1044 | ||
1045 | static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1046 | { | |
1047 | grant_lock(r, lkb); | |
1048 | if (is_master_copy(lkb)) | |
1049 | send_grant(r, lkb); | |
1050 | else | |
1051 | queue_cast(r, lkb, 0); | |
1052 | } | |
1053 | ||
1054 | static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head) | |
1055 | { | |
1056 | struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb, | |
1057 | lkb_statequeue); | |
1058 | if (lkb->lkb_id == first->lkb_id) | |
90135925 | 1059 | return 1; |
e7fd4179 | 1060 | |
90135925 | 1061 | return 0; |
e7fd4179 DT |
1062 | } |
1063 | ||
e7fd4179 DT |
1064 | /* Check if the given lkb conflicts with another lkb on the queue. */ |
1065 | ||
1066 | static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb) | |
1067 | { | |
1068 | struct dlm_lkb *this; | |
1069 | ||
1070 | list_for_each_entry(this, head, lkb_statequeue) { | |
1071 | if (this == lkb) | |
1072 | continue; | |
3bcd3687 | 1073 | if (!modes_compat(this, lkb)) |
90135925 | 1074 | return 1; |
e7fd4179 | 1075 | } |
90135925 | 1076 | return 0; |
e7fd4179 DT |
1077 | } |
1078 | ||
1079 | /* | |
1080 | * "A conversion deadlock arises with a pair of lock requests in the converting | |
1081 | * queue for one resource. The granted mode of each lock blocks the requested | |
1082 | * mode of the other lock." | |
1083 | * | |
1084 | * Part 2: if the granted mode of lkb is preventing the first lkb in the | |
1085 | * convert queue from being granted, then demote lkb (set grmode to NL). | |
1086 | * This second form requires that we check for conv-deadlk even when | |
1087 | * now == 0 in _can_be_granted(). | |
1088 | * | |
1089 | * Example: | |
1090 | * Granted Queue: empty | |
1091 | * Convert Queue: NL->EX (first lock) | |
1092 | * PR->EX (second lock) | |
1093 | * | |
1094 | * The first lock can't be granted because of the granted mode of the second | |
1095 | * lock and the second lock can't be granted because it's not first in the | |
1096 | * list. We demote the granted mode of the second lock (the lkb passed to this | |
1097 | * function). | |
1098 | * | |
1099 | * After the resolution, the "grant pending" function needs to go back and try | |
1100 | * to grant locks on the convert queue again since the first lock can now be | |
1101 | * granted. | |
1102 | */ | |
1103 | ||
1104 | static int conversion_deadlock_detect(struct dlm_rsb *rsb, struct dlm_lkb *lkb) | |
1105 | { | |
1106 | struct dlm_lkb *this, *first = NULL, *self = NULL; | |
1107 | ||
1108 | list_for_each_entry(this, &rsb->res_convertqueue, lkb_statequeue) { | |
1109 | if (!first) | |
1110 | first = this; | |
1111 | if (this == lkb) { | |
1112 | self = lkb; | |
1113 | continue; | |
1114 | } | |
1115 | ||
e7fd4179 | 1116 | if (!modes_compat(this, lkb) && !modes_compat(lkb, this)) |
90135925 | 1117 | return 1; |
e7fd4179 DT |
1118 | } |
1119 | ||
1120 | /* if lkb is on the convert queue and is preventing the first | |
1121 | from being granted, then there's deadlock and we demote lkb. | |
1122 | multiple converting locks may need to do this before the first | |
1123 | converting lock can be granted. */ | |
1124 | ||
1125 | if (self && self != first) { | |
1126 | if (!modes_compat(lkb, first) && | |
1127 | !queue_conflict(&rsb->res_grantqueue, first)) | |
90135925 | 1128 | return 1; |
e7fd4179 DT |
1129 | } |
1130 | ||
90135925 | 1131 | return 0; |
e7fd4179 DT |
1132 | } |
1133 | ||
1134 | /* | |
1135 | * Return 1 if the lock can be granted, 0 otherwise. | |
1136 | * Also detect and resolve conversion deadlocks. | |
1137 | * | |
1138 | * lkb is the lock to be granted | |
1139 | * | |
1140 | * now is 1 if the function is being called in the context of the | |
1141 | * immediate request, it is 0 if called later, after the lock has been | |
1142 | * queued. | |
1143 | * | |
1144 | * References are from chapter 6 of "VAXcluster Principles" by Roy Davis | |
1145 | */ | |
1146 | ||
1147 | static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) | |
1148 | { | |
1149 | int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV); | |
1150 | ||
1151 | /* | |
1152 | * 6-10: Version 5.4 introduced an option to address the phenomenon of | |
1153 | * a new request for a NL mode lock being blocked. | |
1154 | * | |
1155 | * 6-11: If the optional EXPEDITE flag is used with the new NL mode | |
1156 | * request, then it would be granted. In essence, the use of this flag | |
1157 | * tells the Lock Manager to expedite theis request by not considering | |
1158 | * what may be in the CONVERTING or WAITING queues... As of this | |
1159 | * writing, the EXPEDITE flag can be used only with new requests for NL | |
1160 | * mode locks. This flag is not valid for conversion requests. | |
1161 | * | |
1162 | * A shortcut. Earlier checks return an error if EXPEDITE is used in a | |
1163 | * conversion or used with a non-NL requested mode. We also know an | |
1164 | * EXPEDITE request is always granted immediately, so now must always | |
1165 | * be 1. The full condition to grant an expedite request: (now && | |
1166 | * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can | |
1167 | * therefore be shortened to just checking the flag. | |
1168 | */ | |
1169 | ||
1170 | if (lkb->lkb_exflags & DLM_LKF_EXPEDITE) | |
90135925 | 1171 | return 1; |
e7fd4179 DT |
1172 | |
1173 | /* | |
1174 | * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be | |
1175 | * added to the remaining conditions. | |
1176 | */ | |
1177 | ||
1178 | if (queue_conflict(&r->res_grantqueue, lkb)) | |
1179 | goto out; | |
1180 | ||
1181 | /* | |
1182 | * 6-3: By default, a conversion request is immediately granted if the | |
1183 | * requested mode is compatible with the modes of all other granted | |
1184 | * locks | |
1185 | */ | |
1186 | ||
1187 | if (queue_conflict(&r->res_convertqueue, lkb)) | |
1188 | goto out; | |
1189 | ||
1190 | /* | |
1191 | * 6-5: But the default algorithm for deciding whether to grant or | |
1192 | * queue conversion requests does not by itself guarantee that such | |
1193 | * requests are serviced on a "first come first serve" basis. This, in | |
1194 | * turn, can lead to a phenomenon known as "indefinate postponement". | |
1195 | * | |
1196 | * 6-7: This issue is dealt with by using the optional QUECVT flag with | |
1197 | * the system service employed to request a lock conversion. This flag | |
1198 | * forces certain conversion requests to be queued, even if they are | |
1199 | * compatible with the granted modes of other locks on the same | |
1200 | * resource. Thus, the use of this flag results in conversion requests | |
1201 | * being ordered on a "first come first servce" basis. | |
1202 | * | |
1203 | * DCT: This condition is all about new conversions being able to occur | |
1204 | * "in place" while the lock remains on the granted queue (assuming | |
1205 | * nothing else conflicts.) IOW if QUECVT isn't set, a conversion | |
1206 | * doesn't _have_ to go onto the convert queue where it's processed in | |
1207 | * order. The "now" variable is necessary to distinguish converts | |
1208 | * being received and processed for the first time now, because once a | |
1209 | * convert is moved to the conversion queue the condition below applies | |
1210 | * requiring fifo granting. | |
1211 | */ | |
1212 | ||
1213 | if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT)) | |
90135925 | 1214 | return 1; |
e7fd4179 DT |
1215 | |
1216 | /* | |
3bcd3687 DT |
1217 | * The NOORDER flag is set to avoid the standard vms rules on grant |
1218 | * order. | |
e7fd4179 DT |
1219 | */ |
1220 | ||
1221 | if (lkb->lkb_exflags & DLM_LKF_NOORDER) | |
90135925 | 1222 | return 1; |
e7fd4179 DT |
1223 | |
1224 | /* | |
1225 | * 6-3: Once in that queue [CONVERTING], a conversion request cannot be | |
1226 | * granted until all other conversion requests ahead of it are granted | |
1227 | * and/or canceled. | |
1228 | */ | |
1229 | ||
1230 | if (!now && conv && first_in_list(lkb, &r->res_convertqueue)) | |
90135925 | 1231 | return 1; |
e7fd4179 DT |
1232 | |
1233 | /* | |
1234 | * 6-4: By default, a new request is immediately granted only if all | |
1235 | * three of the following conditions are satisfied when the request is | |
1236 | * issued: | |
1237 | * - The queue of ungranted conversion requests for the resource is | |
1238 | * empty. | |
1239 | * - The queue of ungranted new requests for the resource is empty. | |
1240 | * - The mode of the new request is compatible with the most | |
1241 | * restrictive mode of all granted locks on the resource. | |
1242 | */ | |
1243 | ||
1244 | if (now && !conv && list_empty(&r->res_convertqueue) && | |
1245 | list_empty(&r->res_waitqueue)) | |
90135925 | 1246 | return 1; |
e7fd4179 DT |
1247 | |
1248 | /* | |
1249 | * 6-4: Once a lock request is in the queue of ungranted new requests, | |
1250 | * it cannot be granted until the queue of ungranted conversion | |
1251 | * requests is empty, all ungranted new requests ahead of it are | |
1252 | * granted and/or canceled, and it is compatible with the granted mode | |
1253 | * of the most restrictive lock granted on the resource. | |
1254 | */ | |
1255 | ||
1256 | if (!now && !conv && list_empty(&r->res_convertqueue) && | |
1257 | first_in_list(lkb, &r->res_waitqueue)) | |
90135925 | 1258 | return 1; |
e7fd4179 DT |
1259 | |
1260 | out: | |
1261 | /* | |
1262 | * The following, enabled by CONVDEADLK, departs from VMS. | |
1263 | */ | |
1264 | ||
1265 | if (conv && (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) && | |
1266 | conversion_deadlock_detect(r, lkb)) { | |
1267 | lkb->lkb_grmode = DLM_LOCK_NL; | |
1268 | lkb->lkb_sbflags |= DLM_SBF_DEMOTED; | |
1269 | } | |
1270 | ||
90135925 | 1271 | return 0; |
e7fd4179 DT |
1272 | } |
1273 | ||
1274 | /* | |
1275 | * The ALTPR and ALTCW flags aren't traditional lock manager flags, but are a | |
1276 | * simple way to provide a big optimization to applications that can use them. | |
1277 | */ | |
1278 | ||
1279 | static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) | |
1280 | { | |
1281 | uint32_t flags = lkb->lkb_exflags; | |
1282 | int rv; | |
1283 | int8_t alt = 0, rqmode = lkb->lkb_rqmode; | |
1284 | ||
1285 | rv = _can_be_granted(r, lkb, now); | |
1286 | if (rv) | |
1287 | goto out; | |
1288 | ||
1289 | if (lkb->lkb_sbflags & DLM_SBF_DEMOTED) | |
1290 | goto out; | |
1291 | ||
1292 | if (rqmode != DLM_LOCK_PR && flags & DLM_LKF_ALTPR) | |
1293 | alt = DLM_LOCK_PR; | |
1294 | else if (rqmode != DLM_LOCK_CW && flags & DLM_LKF_ALTCW) | |
1295 | alt = DLM_LOCK_CW; | |
1296 | ||
1297 | if (alt) { | |
1298 | lkb->lkb_rqmode = alt; | |
1299 | rv = _can_be_granted(r, lkb, now); | |
1300 | if (rv) | |
1301 | lkb->lkb_sbflags |= DLM_SBF_ALTMODE; | |
1302 | else | |
1303 | lkb->lkb_rqmode = rqmode; | |
1304 | } | |
1305 | out: | |
1306 | return rv; | |
1307 | } | |
1308 | ||
1309 | static int grant_pending_convert(struct dlm_rsb *r, int high) | |
1310 | { | |
1311 | struct dlm_lkb *lkb, *s; | |
1312 | int hi, demoted, quit, grant_restart, demote_restart; | |
1313 | ||
1314 | quit = 0; | |
1315 | restart: | |
1316 | grant_restart = 0; | |
1317 | demote_restart = 0; | |
1318 | hi = DLM_LOCK_IV; | |
1319 | ||
1320 | list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) { | |
1321 | demoted = is_demoted(lkb); | |
90135925 | 1322 | if (can_be_granted(r, lkb, 0)) { |
e7fd4179 DT |
1323 | grant_lock_pending(r, lkb); |
1324 | grant_restart = 1; | |
1325 | } else { | |
1326 | hi = max_t(int, lkb->lkb_rqmode, hi); | |
1327 | if (!demoted && is_demoted(lkb)) | |
1328 | demote_restart = 1; | |
1329 | } | |
1330 | } | |
1331 | ||
1332 | if (grant_restart) | |
1333 | goto restart; | |
1334 | if (demote_restart && !quit) { | |
1335 | quit = 1; | |
1336 | goto restart; | |
1337 | } | |
1338 | ||
1339 | return max_t(int, high, hi); | |
1340 | } | |
1341 | ||
1342 | static int grant_pending_wait(struct dlm_rsb *r, int high) | |
1343 | { | |
1344 | struct dlm_lkb *lkb, *s; | |
1345 | ||
1346 | list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) { | |
90135925 | 1347 | if (can_be_granted(r, lkb, 0)) |
e7fd4179 DT |
1348 | grant_lock_pending(r, lkb); |
1349 | else | |
1350 | high = max_t(int, lkb->lkb_rqmode, high); | |
1351 | } | |
1352 | ||
1353 | return high; | |
1354 | } | |
1355 | ||
1356 | static void grant_pending_locks(struct dlm_rsb *r) | |
1357 | { | |
1358 | struct dlm_lkb *lkb, *s; | |
1359 | int high = DLM_LOCK_IV; | |
1360 | ||
a345da3e | 1361 | DLM_ASSERT(is_master(r), dlm_dump_rsb(r);); |
e7fd4179 DT |
1362 | |
1363 | high = grant_pending_convert(r, high); | |
1364 | high = grant_pending_wait(r, high); | |
1365 | ||
1366 | if (high == DLM_LOCK_IV) | |
1367 | return; | |
1368 | ||
1369 | /* | |
1370 | * If there are locks left on the wait/convert queue then send blocking | |
1371 | * ASTs to granted locks based on the largest requested mode (high) | |
3bcd3687 | 1372 | * found above. FIXME: highbast < high comparison not valid for PR/CW. |
e7fd4179 DT |
1373 | */ |
1374 | ||
1375 | list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) { | |
1376 | if (lkb->lkb_bastaddr && (lkb->lkb_highbast < high) && | |
1377 | !__dlm_compat_matrix[lkb->lkb_grmode+1][high+1]) { | |
1378 | queue_bast(r, lkb, high); | |
1379 | lkb->lkb_highbast = high; | |
1380 | } | |
1381 | } | |
1382 | } | |
1383 | ||
1384 | static void send_bast_queue(struct dlm_rsb *r, struct list_head *head, | |
1385 | struct dlm_lkb *lkb) | |
1386 | { | |
1387 | struct dlm_lkb *gr; | |
1388 | ||
1389 | list_for_each_entry(gr, head, lkb_statequeue) { | |
1390 | if (gr->lkb_bastaddr && | |
1391 | gr->lkb_highbast < lkb->lkb_rqmode && | |
3bcd3687 | 1392 | !modes_compat(gr, lkb)) { |
e7fd4179 DT |
1393 | queue_bast(r, gr, lkb->lkb_rqmode); |
1394 | gr->lkb_highbast = lkb->lkb_rqmode; | |
1395 | } | |
1396 | } | |
1397 | } | |
1398 | ||
1399 | static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1400 | { | |
1401 | send_bast_queue(r, &r->res_grantqueue, lkb); | |
1402 | } | |
1403 | ||
1404 | static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1405 | { | |
1406 | send_bast_queue(r, &r->res_grantqueue, lkb); | |
1407 | send_bast_queue(r, &r->res_convertqueue, lkb); | |
1408 | } | |
1409 | ||
1410 | /* set_master(r, lkb) -- set the master nodeid of a resource | |
1411 | ||
1412 | The purpose of this function is to set the nodeid field in the given | |
1413 | lkb using the nodeid field in the given rsb. If the rsb's nodeid is | |
1414 | known, it can just be copied to the lkb and the function will return | |
1415 | 0. If the rsb's nodeid is _not_ known, it needs to be looked up | |
1416 | before it can be copied to the lkb. | |
1417 | ||
1418 | When the rsb nodeid is being looked up remotely, the initial lkb | |
1419 | causing the lookup is kept on the ls_waiters list waiting for the | |
1420 | lookup reply. Other lkb's waiting for the same rsb lookup are kept | |
1421 | on the rsb's res_lookup list until the master is verified. | |
1422 | ||
1423 | Return values: | |
1424 | 0: nodeid is set in rsb/lkb and the caller should go ahead and use it | |
1425 | 1: the rsb master is not available and the lkb has been placed on | |
1426 | a wait queue | |
1427 | */ | |
1428 | ||
1429 | static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1430 | { | |
1431 | struct dlm_ls *ls = r->res_ls; | |
1432 | int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid(); | |
1433 | ||
1434 | if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) { | |
1435 | rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); | |
1436 | r->res_first_lkid = lkb->lkb_id; | |
1437 | lkb->lkb_nodeid = r->res_nodeid; | |
1438 | return 0; | |
1439 | } | |
1440 | ||
1441 | if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) { | |
1442 | list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup); | |
1443 | return 1; | |
1444 | } | |
1445 | ||
1446 | if (r->res_nodeid == 0) { | |
1447 | lkb->lkb_nodeid = 0; | |
1448 | return 0; | |
1449 | } | |
1450 | ||
1451 | if (r->res_nodeid > 0) { | |
1452 | lkb->lkb_nodeid = r->res_nodeid; | |
1453 | return 0; | |
1454 | } | |
1455 | ||
a345da3e | 1456 | DLM_ASSERT(r->res_nodeid == -1, dlm_dump_rsb(r);); |
e7fd4179 DT |
1457 | |
1458 | dir_nodeid = dlm_dir_nodeid(r); | |
1459 | ||
1460 | if (dir_nodeid != our_nodeid) { | |
1461 | r->res_first_lkid = lkb->lkb_id; | |
1462 | send_lookup(r, lkb); | |
1463 | return 1; | |
1464 | } | |
1465 | ||
1466 | for (;;) { | |
1467 | /* It's possible for dlm_scand to remove an old rsb for | |
1468 | this same resource from the toss list, us to create | |
1469 | a new one, look up the master locally, and find it | |
1470 | already exists just before dlm_scand does the | |
1471 | dir_remove() on the previous rsb. */ | |
1472 | ||
1473 | error = dlm_dir_lookup(ls, our_nodeid, r->res_name, | |
1474 | r->res_length, &ret_nodeid); | |
1475 | if (!error) | |
1476 | break; | |
1477 | log_debug(ls, "dir_lookup error %d %s", error, r->res_name); | |
1478 | schedule(); | |
1479 | } | |
1480 | ||
1481 | if (ret_nodeid == our_nodeid) { | |
1482 | r->res_first_lkid = 0; | |
1483 | r->res_nodeid = 0; | |
1484 | lkb->lkb_nodeid = 0; | |
1485 | } else { | |
1486 | r->res_first_lkid = lkb->lkb_id; | |
1487 | r->res_nodeid = ret_nodeid; | |
1488 | lkb->lkb_nodeid = ret_nodeid; | |
1489 | } | |
1490 | return 0; | |
1491 | } | |
1492 | ||
1493 | static void process_lookup_list(struct dlm_rsb *r) | |
1494 | { | |
1495 | struct dlm_lkb *lkb, *safe; | |
1496 | ||
1497 | list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) { | |
1498 | list_del(&lkb->lkb_rsb_lookup); | |
1499 | _request_lock(r, lkb); | |
1500 | schedule(); | |
1501 | } | |
1502 | } | |
1503 | ||
1504 | /* confirm_master -- confirm (or deny) an rsb's master nodeid */ | |
1505 | ||
1506 | static void confirm_master(struct dlm_rsb *r, int error) | |
1507 | { | |
1508 | struct dlm_lkb *lkb; | |
1509 | ||
1510 | if (!r->res_first_lkid) | |
1511 | return; | |
1512 | ||
1513 | switch (error) { | |
1514 | case 0: | |
1515 | case -EINPROGRESS: | |
1516 | r->res_first_lkid = 0; | |
1517 | process_lookup_list(r); | |
1518 | break; | |
1519 | ||
1520 | case -EAGAIN: | |
1521 | /* the remote master didn't queue our NOQUEUE request; | |
1522 | make a waiting lkb the first_lkid */ | |
1523 | ||
1524 | r->res_first_lkid = 0; | |
1525 | ||
1526 | if (!list_empty(&r->res_lookup)) { | |
1527 | lkb = list_entry(r->res_lookup.next, struct dlm_lkb, | |
1528 | lkb_rsb_lookup); | |
1529 | list_del(&lkb->lkb_rsb_lookup); | |
1530 | r->res_first_lkid = lkb->lkb_id; | |
1531 | _request_lock(r, lkb); | |
1532 | } else | |
1533 | r->res_nodeid = -1; | |
1534 | break; | |
1535 | ||
1536 | default: | |
1537 | log_error(r->res_ls, "confirm_master unknown error %d", error); | |
1538 | } | |
1539 | } | |
1540 | ||
1541 | static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags, | |
1542 | int namelen, uint32_t parent_lkid, void *ast, | |
3bcd3687 | 1543 | void *astarg, void *bast, struct dlm_args *args) |
e7fd4179 DT |
1544 | { |
1545 | int rv = -EINVAL; | |
1546 | ||
1547 | /* check for invalid arg usage */ | |
1548 | ||
1549 | if (mode < 0 || mode > DLM_LOCK_EX) | |
1550 | goto out; | |
1551 | ||
1552 | if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN)) | |
1553 | goto out; | |
1554 | ||
1555 | if (flags & DLM_LKF_CANCEL) | |
1556 | goto out; | |
1557 | ||
1558 | if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT)) | |
1559 | goto out; | |
1560 | ||
1561 | if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT)) | |
1562 | goto out; | |
1563 | ||
1564 | if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE) | |
1565 | goto out; | |
1566 | ||
1567 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT) | |
1568 | goto out; | |
1569 | ||
1570 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT) | |
1571 | goto out; | |
1572 | ||
1573 | if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE) | |
1574 | goto out; | |
1575 | ||
1576 | if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL) | |
1577 | goto out; | |
1578 | ||
1579 | if (!ast || !lksb) | |
1580 | goto out; | |
1581 | ||
1582 | if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr) | |
1583 | goto out; | |
1584 | ||
1585 | /* parent/child locks not yet supported */ | |
1586 | if (parent_lkid) | |
1587 | goto out; | |
1588 | ||
1589 | if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid) | |
1590 | goto out; | |
1591 | ||
1592 | /* these args will be copied to the lkb in validate_lock_args, | |
1593 | it cannot be done now because when converting locks, fields in | |
1594 | an active lkb cannot be modified before locking the rsb */ | |
1595 | ||
1596 | args->flags = flags; | |
1597 | args->astaddr = ast; | |
1598 | args->astparam = (long) astarg; | |
1599 | args->bastaddr = bast; | |
1600 | args->mode = mode; | |
1601 | args->lksb = lksb; | |
e7fd4179 DT |
1602 | rv = 0; |
1603 | out: | |
1604 | return rv; | |
1605 | } | |
1606 | ||
1607 | static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args) | |
1608 | { | |
1609 | if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK | | |
1610 | DLM_LKF_FORCEUNLOCK)) | |
1611 | return -EINVAL; | |
1612 | ||
1613 | args->flags = flags; | |
1614 | args->astparam = (long) astarg; | |
1615 | return 0; | |
1616 | } | |
1617 | ||
1618 | static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1619 | struct dlm_args *args) | |
1620 | { | |
1621 | int rv = -EINVAL; | |
1622 | ||
1623 | if (args->flags & DLM_LKF_CONVERT) { | |
1624 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
1625 | goto out; | |
1626 | ||
1627 | if (args->flags & DLM_LKF_QUECVT && | |
1628 | !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1]) | |
1629 | goto out; | |
1630 | ||
1631 | rv = -EBUSY; | |
1632 | if (lkb->lkb_status != DLM_LKSTS_GRANTED) | |
1633 | goto out; | |
1634 | ||
1635 | if (lkb->lkb_wait_type) | |
1636 | goto out; | |
1637 | } | |
1638 | ||
1639 | lkb->lkb_exflags = args->flags; | |
1640 | lkb->lkb_sbflags = 0; | |
1641 | lkb->lkb_astaddr = args->astaddr; | |
1642 | lkb->lkb_astparam = args->astparam; | |
1643 | lkb->lkb_bastaddr = args->bastaddr; | |
1644 | lkb->lkb_rqmode = args->mode; | |
1645 | lkb->lkb_lksb = args->lksb; | |
1646 | lkb->lkb_lvbptr = args->lksb->sb_lvbptr; | |
1647 | lkb->lkb_ownpid = (int) current->pid; | |
e7fd4179 DT |
1648 | rv = 0; |
1649 | out: | |
1650 | return rv; | |
1651 | } | |
1652 | ||
1653 | static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args) | |
1654 | { | |
1655 | int rv = -EINVAL; | |
1656 | ||
1657 | if (lkb->lkb_flags & DLM_IFL_MSTCPY) | |
1658 | goto out; | |
1659 | ||
1660 | if (args->flags & DLM_LKF_FORCEUNLOCK) | |
1661 | goto out_ok; | |
1662 | ||
1663 | if (args->flags & DLM_LKF_CANCEL && | |
1664 | lkb->lkb_status == DLM_LKSTS_GRANTED) | |
1665 | goto out; | |
1666 | ||
1667 | if (!(args->flags & DLM_LKF_CANCEL) && | |
1668 | lkb->lkb_status != DLM_LKSTS_GRANTED) | |
1669 | goto out; | |
1670 | ||
1671 | rv = -EBUSY; | |
1672 | if (lkb->lkb_wait_type) | |
1673 | goto out; | |
1674 | ||
1675 | out_ok: | |
1676 | lkb->lkb_exflags = args->flags; | |
1677 | lkb->lkb_sbflags = 0; | |
1678 | lkb->lkb_astparam = args->astparam; | |
1679 | ||
1680 | rv = 0; | |
1681 | out: | |
1682 | return rv; | |
1683 | } | |
1684 | ||
1685 | /* | |
1686 | * Four stage 4 varieties: | |
1687 | * do_request(), do_convert(), do_unlock(), do_cancel() | |
1688 | * These are called on the master node for the given lock and | |
1689 | * from the central locking logic. | |
1690 | */ | |
1691 | ||
1692 | static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1693 | { | |
1694 | int error = 0; | |
1695 | ||
90135925 | 1696 | if (can_be_granted(r, lkb, 1)) { |
e7fd4179 DT |
1697 | grant_lock(r, lkb); |
1698 | queue_cast(r, lkb, 0); | |
1699 | goto out; | |
1700 | } | |
1701 | ||
1702 | if (can_be_queued(lkb)) { | |
1703 | error = -EINPROGRESS; | |
1704 | add_lkb(r, lkb, DLM_LKSTS_WAITING); | |
1705 | send_blocking_asts(r, lkb); | |
1706 | goto out; | |
1707 | } | |
1708 | ||
1709 | error = -EAGAIN; | |
1710 | if (force_blocking_asts(lkb)) | |
1711 | send_blocking_asts_all(r, lkb); | |
1712 | queue_cast(r, lkb, -EAGAIN); | |
1713 | ||
1714 | out: | |
1715 | return error; | |
1716 | } | |
1717 | ||
1718 | static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1719 | { | |
1720 | int error = 0; | |
1721 | ||
1722 | /* changing an existing lock may allow others to be granted */ | |
1723 | ||
90135925 | 1724 | if (can_be_granted(r, lkb, 1)) { |
e7fd4179 DT |
1725 | grant_lock(r, lkb); |
1726 | queue_cast(r, lkb, 0); | |
1727 | grant_pending_locks(r); | |
1728 | goto out; | |
1729 | } | |
1730 | ||
1731 | if (can_be_queued(lkb)) { | |
1732 | if (is_demoted(lkb)) | |
1733 | grant_pending_locks(r); | |
1734 | error = -EINPROGRESS; | |
1735 | del_lkb(r, lkb); | |
1736 | add_lkb(r, lkb, DLM_LKSTS_CONVERT); | |
1737 | send_blocking_asts(r, lkb); | |
1738 | goto out; | |
1739 | } | |
1740 | ||
1741 | error = -EAGAIN; | |
1742 | if (force_blocking_asts(lkb)) | |
1743 | send_blocking_asts_all(r, lkb); | |
1744 | queue_cast(r, lkb, -EAGAIN); | |
1745 | ||
1746 | out: | |
1747 | return error; | |
1748 | } | |
1749 | ||
1750 | static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1751 | { | |
1752 | remove_lock(r, lkb); | |
1753 | queue_cast(r, lkb, -DLM_EUNLOCK); | |
1754 | grant_pending_locks(r); | |
1755 | return -DLM_EUNLOCK; | |
1756 | } | |
1757 | ||
597d0cae DT |
1758 | /* FIXME: if revert_lock() finds that the lkb is granted, we should |
1759 | skip the queue_cast(ECANCEL). It indicates that the request/convert | |
1760 | completed (and queued a normal ast) just before the cancel; we don't | |
1761 | want to clobber the sb_result for the normal ast with ECANCEL. */ | |
1762 | ||
e7fd4179 DT |
1763 | static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) |
1764 | { | |
1765 | revert_lock(r, lkb); | |
1766 | queue_cast(r, lkb, -DLM_ECANCEL); | |
1767 | grant_pending_locks(r); | |
1768 | return -DLM_ECANCEL; | |
1769 | } | |
1770 | ||
1771 | /* | |
1772 | * Four stage 3 varieties: | |
1773 | * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock() | |
1774 | */ | |
1775 | ||
1776 | /* add a new lkb to a possibly new rsb, called by requesting process */ | |
1777 | ||
1778 | static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1779 | { | |
1780 | int error; | |
1781 | ||
1782 | /* set_master: sets lkb nodeid from r */ | |
1783 | ||
1784 | error = set_master(r, lkb); | |
1785 | if (error < 0) | |
1786 | goto out; | |
1787 | if (error) { | |
1788 | error = 0; | |
1789 | goto out; | |
1790 | } | |
1791 | ||
1792 | if (is_remote(r)) | |
1793 | /* receive_request() calls do_request() on remote node */ | |
1794 | error = send_request(r, lkb); | |
1795 | else | |
1796 | error = do_request(r, lkb); | |
1797 | out: | |
1798 | return error; | |
1799 | } | |
1800 | ||
3bcd3687 | 1801 | /* change some property of an existing lkb, e.g. mode */ |
e7fd4179 DT |
1802 | |
1803 | static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1804 | { | |
1805 | int error; | |
1806 | ||
1807 | if (is_remote(r)) | |
1808 | /* receive_convert() calls do_convert() on remote node */ | |
1809 | error = send_convert(r, lkb); | |
1810 | else | |
1811 | error = do_convert(r, lkb); | |
1812 | ||
1813 | return error; | |
1814 | } | |
1815 | ||
1816 | /* remove an existing lkb from the granted queue */ | |
1817 | ||
1818 | static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1819 | { | |
1820 | int error; | |
1821 | ||
1822 | if (is_remote(r)) | |
1823 | /* receive_unlock() calls do_unlock() on remote node */ | |
1824 | error = send_unlock(r, lkb); | |
1825 | else | |
1826 | error = do_unlock(r, lkb); | |
1827 | ||
1828 | return error; | |
1829 | } | |
1830 | ||
1831 | /* remove an existing lkb from the convert or wait queue */ | |
1832 | ||
1833 | static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
1834 | { | |
1835 | int error; | |
1836 | ||
1837 | if (is_remote(r)) | |
1838 | /* receive_cancel() calls do_cancel() on remote node */ | |
1839 | error = send_cancel(r, lkb); | |
1840 | else | |
1841 | error = do_cancel(r, lkb); | |
1842 | ||
1843 | return error; | |
1844 | } | |
1845 | ||
1846 | /* | |
1847 | * Four stage 2 varieties: | |
1848 | * request_lock(), convert_lock(), unlock_lock(), cancel_lock() | |
1849 | */ | |
1850 | ||
1851 | static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name, | |
1852 | int len, struct dlm_args *args) | |
1853 | { | |
1854 | struct dlm_rsb *r; | |
1855 | int error; | |
1856 | ||
1857 | error = validate_lock_args(ls, lkb, args); | |
1858 | if (error) | |
1859 | goto out; | |
1860 | ||
1861 | error = find_rsb(ls, name, len, R_CREATE, &r); | |
1862 | if (error) | |
1863 | goto out; | |
1864 | ||
1865 | lock_rsb(r); | |
1866 | ||
1867 | attach_lkb(r, lkb); | |
1868 | lkb->lkb_lksb->sb_lkid = lkb->lkb_id; | |
1869 | ||
1870 | error = _request_lock(r, lkb); | |
1871 | ||
1872 | unlock_rsb(r); | |
1873 | put_rsb(r); | |
1874 | ||
1875 | out: | |
1876 | return error; | |
1877 | } | |
1878 | ||
1879 | static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1880 | struct dlm_args *args) | |
1881 | { | |
1882 | struct dlm_rsb *r; | |
1883 | int error; | |
1884 | ||
1885 | r = lkb->lkb_resource; | |
1886 | ||
1887 | hold_rsb(r); | |
1888 | lock_rsb(r); | |
1889 | ||
1890 | error = validate_lock_args(ls, lkb, args); | |
1891 | if (error) | |
1892 | goto out; | |
1893 | ||
1894 | error = _convert_lock(r, lkb); | |
1895 | out: | |
1896 | unlock_rsb(r); | |
1897 | put_rsb(r); | |
1898 | return error; | |
1899 | } | |
1900 | ||
1901 | static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1902 | struct dlm_args *args) | |
1903 | { | |
1904 | struct dlm_rsb *r; | |
1905 | int error; | |
1906 | ||
1907 | r = lkb->lkb_resource; | |
1908 | ||
1909 | hold_rsb(r); | |
1910 | lock_rsb(r); | |
1911 | ||
1912 | error = validate_unlock_args(lkb, args); | |
1913 | if (error) | |
1914 | goto out; | |
1915 | ||
1916 | error = _unlock_lock(r, lkb); | |
1917 | out: | |
1918 | unlock_rsb(r); | |
1919 | put_rsb(r); | |
1920 | return error; | |
1921 | } | |
1922 | ||
1923 | static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
1924 | struct dlm_args *args) | |
1925 | { | |
1926 | struct dlm_rsb *r; | |
1927 | int error; | |
1928 | ||
1929 | r = lkb->lkb_resource; | |
1930 | ||
1931 | hold_rsb(r); | |
1932 | lock_rsb(r); | |
1933 | ||
1934 | error = validate_unlock_args(lkb, args); | |
1935 | if (error) | |
1936 | goto out; | |
1937 | ||
1938 | error = _cancel_lock(r, lkb); | |
1939 | out: | |
1940 | unlock_rsb(r); | |
1941 | put_rsb(r); | |
1942 | return error; | |
1943 | } | |
1944 | ||
1945 | /* | |
1946 | * Two stage 1 varieties: dlm_lock() and dlm_unlock() | |
1947 | */ | |
1948 | ||
1949 | int dlm_lock(dlm_lockspace_t *lockspace, | |
1950 | int mode, | |
1951 | struct dlm_lksb *lksb, | |
1952 | uint32_t flags, | |
1953 | void *name, | |
1954 | unsigned int namelen, | |
1955 | uint32_t parent_lkid, | |
1956 | void (*ast) (void *astarg), | |
1957 | void *astarg, | |
3bcd3687 | 1958 | void (*bast) (void *astarg, int mode)) |
e7fd4179 DT |
1959 | { |
1960 | struct dlm_ls *ls; | |
1961 | struct dlm_lkb *lkb; | |
1962 | struct dlm_args args; | |
1963 | int error, convert = flags & DLM_LKF_CONVERT; | |
1964 | ||
1965 | ls = dlm_find_lockspace_local(lockspace); | |
1966 | if (!ls) | |
1967 | return -EINVAL; | |
1968 | ||
1969 | lock_recovery(ls); | |
1970 | ||
1971 | if (convert) | |
1972 | error = find_lkb(ls, lksb->sb_lkid, &lkb); | |
1973 | else | |
1974 | error = create_lkb(ls, &lkb); | |
1975 | ||
1976 | if (error) | |
1977 | goto out; | |
1978 | ||
1979 | error = set_lock_args(mode, lksb, flags, namelen, parent_lkid, ast, | |
3bcd3687 | 1980 | astarg, bast, &args); |
e7fd4179 DT |
1981 | if (error) |
1982 | goto out_put; | |
1983 | ||
1984 | if (convert) | |
1985 | error = convert_lock(ls, lkb, &args); | |
1986 | else | |
1987 | error = request_lock(ls, lkb, name, namelen, &args); | |
1988 | ||
1989 | if (error == -EINPROGRESS) | |
1990 | error = 0; | |
1991 | out_put: | |
1992 | if (convert || error) | |
b3f58d8f | 1993 | __put_lkb(ls, lkb); |
e7fd4179 DT |
1994 | if (error == -EAGAIN) |
1995 | error = 0; | |
1996 | out: | |
1997 | unlock_recovery(ls); | |
1998 | dlm_put_lockspace(ls); | |
1999 | return error; | |
2000 | } | |
2001 | ||
2002 | int dlm_unlock(dlm_lockspace_t *lockspace, | |
2003 | uint32_t lkid, | |
2004 | uint32_t flags, | |
2005 | struct dlm_lksb *lksb, | |
2006 | void *astarg) | |
2007 | { | |
2008 | struct dlm_ls *ls; | |
2009 | struct dlm_lkb *lkb; | |
2010 | struct dlm_args args; | |
2011 | int error; | |
2012 | ||
2013 | ls = dlm_find_lockspace_local(lockspace); | |
2014 | if (!ls) | |
2015 | return -EINVAL; | |
2016 | ||
2017 | lock_recovery(ls); | |
2018 | ||
2019 | error = find_lkb(ls, lkid, &lkb); | |
2020 | if (error) | |
2021 | goto out; | |
2022 | ||
2023 | error = set_unlock_args(flags, astarg, &args); | |
2024 | if (error) | |
2025 | goto out_put; | |
2026 | ||
2027 | if (flags & DLM_LKF_CANCEL) | |
2028 | error = cancel_lock(ls, lkb, &args); | |
2029 | else | |
2030 | error = unlock_lock(ls, lkb, &args); | |
2031 | ||
2032 | if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL) | |
2033 | error = 0; | |
2034 | out_put: | |
b3f58d8f | 2035 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2036 | out: |
2037 | unlock_recovery(ls); | |
2038 | dlm_put_lockspace(ls); | |
2039 | return error; | |
2040 | } | |
2041 | ||
2042 | /* | |
2043 | * send/receive routines for remote operations and replies | |
2044 | * | |
2045 | * send_args | |
2046 | * send_common | |
2047 | * send_request receive_request | |
2048 | * send_convert receive_convert | |
2049 | * send_unlock receive_unlock | |
2050 | * send_cancel receive_cancel | |
2051 | * send_grant receive_grant | |
2052 | * send_bast receive_bast | |
2053 | * send_lookup receive_lookup | |
2054 | * send_remove receive_remove | |
2055 | * | |
2056 | * send_common_reply | |
2057 | * receive_request_reply send_request_reply | |
2058 | * receive_convert_reply send_convert_reply | |
2059 | * receive_unlock_reply send_unlock_reply | |
2060 | * receive_cancel_reply send_cancel_reply | |
2061 | * receive_lookup_reply send_lookup_reply | |
2062 | */ | |
2063 | ||
2064 | static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2065 | int to_nodeid, int mstype, | |
2066 | struct dlm_message **ms_ret, | |
2067 | struct dlm_mhandle **mh_ret) | |
2068 | { | |
2069 | struct dlm_message *ms; | |
2070 | struct dlm_mhandle *mh; | |
2071 | char *mb; | |
2072 | int mb_len = sizeof(struct dlm_message); | |
2073 | ||
2074 | switch (mstype) { | |
2075 | case DLM_MSG_REQUEST: | |
2076 | case DLM_MSG_LOOKUP: | |
2077 | case DLM_MSG_REMOVE: | |
2078 | mb_len += r->res_length; | |
2079 | break; | |
2080 | case DLM_MSG_CONVERT: | |
2081 | case DLM_MSG_UNLOCK: | |
2082 | case DLM_MSG_REQUEST_REPLY: | |
2083 | case DLM_MSG_CONVERT_REPLY: | |
2084 | case DLM_MSG_GRANT: | |
2085 | if (lkb && lkb->lkb_lvbptr) | |
2086 | mb_len += r->res_ls->ls_lvblen; | |
2087 | break; | |
2088 | } | |
2089 | ||
2090 | /* get_buffer gives us a message handle (mh) that we need to | |
2091 | pass into lowcomms_commit and a message buffer (mb) that we | |
2092 | write our data into */ | |
2093 | ||
2094 | mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb); | |
2095 | if (!mh) | |
2096 | return -ENOBUFS; | |
2097 | ||
2098 | memset(mb, 0, mb_len); | |
2099 | ||
2100 | ms = (struct dlm_message *) mb; | |
2101 | ||
2102 | ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); | |
2103 | ms->m_header.h_lockspace = r->res_ls->ls_global_id; | |
2104 | ms->m_header.h_nodeid = dlm_our_nodeid(); | |
2105 | ms->m_header.h_length = mb_len; | |
2106 | ms->m_header.h_cmd = DLM_MSG; | |
2107 | ||
2108 | ms->m_type = mstype; | |
2109 | ||
2110 | *mh_ret = mh; | |
2111 | *ms_ret = ms; | |
2112 | return 0; | |
2113 | } | |
2114 | ||
2115 | /* further lowcomms enhancements or alternate implementations may make | |
2116 | the return value from this function useful at some point */ | |
2117 | ||
2118 | static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms) | |
2119 | { | |
2120 | dlm_message_out(ms); | |
2121 | dlm_lowcomms_commit_buffer(mh); | |
2122 | return 0; | |
2123 | } | |
2124 | ||
2125 | static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2126 | struct dlm_message *ms) | |
2127 | { | |
2128 | ms->m_nodeid = lkb->lkb_nodeid; | |
2129 | ms->m_pid = lkb->lkb_ownpid; | |
2130 | ms->m_lkid = lkb->lkb_id; | |
2131 | ms->m_remid = lkb->lkb_remid; | |
2132 | ms->m_exflags = lkb->lkb_exflags; | |
2133 | ms->m_sbflags = lkb->lkb_sbflags; | |
2134 | ms->m_flags = lkb->lkb_flags; | |
2135 | ms->m_lvbseq = lkb->lkb_lvbseq; | |
2136 | ms->m_status = lkb->lkb_status; | |
2137 | ms->m_grmode = lkb->lkb_grmode; | |
2138 | ms->m_rqmode = lkb->lkb_rqmode; | |
2139 | ms->m_hash = r->res_hash; | |
2140 | ||
2141 | /* m_result and m_bastmode are set from function args, | |
2142 | not from lkb fields */ | |
2143 | ||
2144 | if (lkb->lkb_bastaddr) | |
2145 | ms->m_asts |= AST_BAST; | |
2146 | if (lkb->lkb_astaddr) | |
2147 | ms->m_asts |= AST_COMP; | |
2148 | ||
e7fd4179 DT |
2149 | if (ms->m_type == DLM_MSG_REQUEST || ms->m_type == DLM_MSG_LOOKUP) |
2150 | memcpy(ms->m_extra, r->res_name, r->res_length); | |
2151 | ||
2152 | else if (lkb->lkb_lvbptr) | |
2153 | memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); | |
2154 | ||
2155 | } | |
2156 | ||
2157 | static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype) | |
2158 | { | |
2159 | struct dlm_message *ms; | |
2160 | struct dlm_mhandle *mh; | |
2161 | int to_nodeid, error; | |
2162 | ||
2163 | add_to_waiters(lkb, mstype); | |
2164 | ||
2165 | to_nodeid = r->res_nodeid; | |
2166 | ||
2167 | error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); | |
2168 | if (error) | |
2169 | goto fail; | |
2170 | ||
2171 | send_args(r, lkb, ms); | |
2172 | ||
2173 | error = send_message(mh, ms); | |
2174 | if (error) | |
2175 | goto fail; | |
2176 | return 0; | |
2177 | ||
2178 | fail: | |
2179 | remove_from_waiters(lkb); | |
2180 | return error; | |
2181 | } | |
2182 | ||
2183 | static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2184 | { | |
2185 | return send_common(r, lkb, DLM_MSG_REQUEST); | |
2186 | } | |
2187 | ||
2188 | static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2189 | { | |
2190 | int error; | |
2191 | ||
2192 | error = send_common(r, lkb, DLM_MSG_CONVERT); | |
2193 | ||
2194 | /* down conversions go without a reply from the master */ | |
2195 | if (!error && down_conversion(lkb)) { | |
2196 | remove_from_waiters(lkb); | |
2197 | r->res_ls->ls_stub_ms.m_result = 0; | |
2198 | __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms); | |
2199 | } | |
2200 | ||
2201 | return error; | |
2202 | } | |
2203 | ||
2204 | /* FIXME: if this lkb is the only lock we hold on the rsb, then set | |
2205 | MASTER_UNCERTAIN to force the next request on the rsb to confirm | |
2206 | that the master is still correct. */ | |
2207 | ||
2208 | static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2209 | { | |
2210 | return send_common(r, lkb, DLM_MSG_UNLOCK); | |
2211 | } | |
2212 | ||
2213 | static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2214 | { | |
2215 | return send_common(r, lkb, DLM_MSG_CANCEL); | |
2216 | } | |
2217 | ||
2218 | static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2219 | { | |
2220 | struct dlm_message *ms; | |
2221 | struct dlm_mhandle *mh; | |
2222 | int to_nodeid, error; | |
2223 | ||
2224 | to_nodeid = lkb->lkb_nodeid; | |
2225 | ||
2226 | error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh); | |
2227 | if (error) | |
2228 | goto out; | |
2229 | ||
2230 | send_args(r, lkb, ms); | |
2231 | ||
2232 | ms->m_result = 0; | |
2233 | ||
2234 | error = send_message(mh, ms); | |
2235 | out: | |
2236 | return error; | |
2237 | } | |
2238 | ||
2239 | static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode) | |
2240 | { | |
2241 | struct dlm_message *ms; | |
2242 | struct dlm_mhandle *mh; | |
2243 | int to_nodeid, error; | |
2244 | ||
2245 | to_nodeid = lkb->lkb_nodeid; | |
2246 | ||
2247 | error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh); | |
2248 | if (error) | |
2249 | goto out; | |
2250 | ||
2251 | send_args(r, lkb, ms); | |
2252 | ||
2253 | ms->m_bastmode = mode; | |
2254 | ||
2255 | error = send_message(mh, ms); | |
2256 | out: | |
2257 | return error; | |
2258 | } | |
2259 | ||
2260 | static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb) | |
2261 | { | |
2262 | struct dlm_message *ms; | |
2263 | struct dlm_mhandle *mh; | |
2264 | int to_nodeid, error; | |
2265 | ||
2266 | add_to_waiters(lkb, DLM_MSG_LOOKUP); | |
2267 | ||
2268 | to_nodeid = dlm_dir_nodeid(r); | |
2269 | ||
2270 | error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh); | |
2271 | if (error) | |
2272 | goto fail; | |
2273 | ||
2274 | send_args(r, lkb, ms); | |
2275 | ||
2276 | error = send_message(mh, ms); | |
2277 | if (error) | |
2278 | goto fail; | |
2279 | return 0; | |
2280 | ||
2281 | fail: | |
2282 | remove_from_waiters(lkb); | |
2283 | return error; | |
2284 | } | |
2285 | ||
2286 | static int send_remove(struct dlm_rsb *r) | |
2287 | { | |
2288 | struct dlm_message *ms; | |
2289 | struct dlm_mhandle *mh; | |
2290 | int to_nodeid, error; | |
2291 | ||
2292 | to_nodeid = dlm_dir_nodeid(r); | |
2293 | ||
2294 | error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh); | |
2295 | if (error) | |
2296 | goto out; | |
2297 | ||
2298 | memcpy(ms->m_extra, r->res_name, r->res_length); | |
2299 | ms->m_hash = r->res_hash; | |
2300 | ||
2301 | error = send_message(mh, ms); | |
2302 | out: | |
2303 | return error; | |
2304 | } | |
2305 | ||
2306 | static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2307 | int mstype, int rv) | |
2308 | { | |
2309 | struct dlm_message *ms; | |
2310 | struct dlm_mhandle *mh; | |
2311 | int to_nodeid, error; | |
2312 | ||
2313 | to_nodeid = lkb->lkb_nodeid; | |
2314 | ||
2315 | error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); | |
2316 | if (error) | |
2317 | goto out; | |
2318 | ||
2319 | send_args(r, lkb, ms); | |
2320 | ||
2321 | ms->m_result = rv; | |
2322 | ||
2323 | error = send_message(mh, ms); | |
2324 | out: | |
2325 | return error; | |
2326 | } | |
2327 | ||
2328 | static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2329 | { | |
2330 | return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv); | |
2331 | } | |
2332 | ||
2333 | static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2334 | { | |
2335 | return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv); | |
2336 | } | |
2337 | ||
2338 | static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2339 | { | |
2340 | return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv); | |
2341 | } | |
2342 | ||
2343 | static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) | |
2344 | { | |
2345 | return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv); | |
2346 | } | |
2347 | ||
2348 | static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in, | |
2349 | int ret_nodeid, int rv) | |
2350 | { | |
2351 | struct dlm_rsb *r = &ls->ls_stub_rsb; | |
2352 | struct dlm_message *ms; | |
2353 | struct dlm_mhandle *mh; | |
2354 | int error, nodeid = ms_in->m_header.h_nodeid; | |
2355 | ||
2356 | error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh); | |
2357 | if (error) | |
2358 | goto out; | |
2359 | ||
2360 | ms->m_lkid = ms_in->m_lkid; | |
2361 | ms->m_result = rv; | |
2362 | ms->m_nodeid = ret_nodeid; | |
2363 | ||
2364 | error = send_message(mh, ms); | |
2365 | out: | |
2366 | return error; | |
2367 | } | |
2368 | ||
2369 | /* which args we save from a received message depends heavily on the type | |
2370 | of message, unlike the send side where we can safely send everything about | |
2371 | the lkb for any type of message */ | |
2372 | ||
2373 | static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2374 | { | |
2375 | lkb->lkb_exflags = ms->m_exflags; | |
2376 | lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | | |
2377 | (ms->m_flags & 0x0000FFFF); | |
2378 | } | |
2379 | ||
2380 | static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2381 | { | |
2382 | lkb->lkb_sbflags = ms->m_sbflags; | |
2383 | lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | | |
2384 | (ms->m_flags & 0x0000FFFF); | |
2385 | } | |
2386 | ||
2387 | static int receive_extralen(struct dlm_message *ms) | |
2388 | { | |
2389 | return (ms->m_header.h_length - sizeof(struct dlm_message)); | |
2390 | } | |
2391 | ||
e7fd4179 DT |
2392 | static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb, |
2393 | struct dlm_message *ms) | |
2394 | { | |
2395 | int len; | |
2396 | ||
2397 | if (lkb->lkb_exflags & DLM_LKF_VALBLK) { | |
2398 | if (!lkb->lkb_lvbptr) | |
2399 | lkb->lkb_lvbptr = allocate_lvb(ls); | |
2400 | if (!lkb->lkb_lvbptr) | |
2401 | return -ENOMEM; | |
2402 | len = receive_extralen(ms); | |
2403 | memcpy(lkb->lkb_lvbptr, ms->m_extra, len); | |
2404 | } | |
2405 | return 0; | |
2406 | } | |
2407 | ||
2408 | static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2409 | struct dlm_message *ms) | |
2410 | { | |
2411 | lkb->lkb_nodeid = ms->m_header.h_nodeid; | |
2412 | lkb->lkb_ownpid = ms->m_pid; | |
2413 | lkb->lkb_remid = ms->m_lkid; | |
2414 | lkb->lkb_grmode = DLM_LOCK_IV; | |
2415 | lkb->lkb_rqmode = ms->m_rqmode; | |
2416 | lkb->lkb_bastaddr = (void *) (long) (ms->m_asts & AST_BAST); | |
2417 | lkb->lkb_astaddr = (void *) (long) (ms->m_asts & AST_COMP); | |
2418 | ||
2419 | DLM_ASSERT(is_master_copy(lkb), dlm_print_lkb(lkb);); | |
2420 | ||
e7fd4179 DT |
2421 | if (receive_lvb(ls, lkb, ms)) |
2422 | return -ENOMEM; | |
2423 | ||
2424 | return 0; | |
2425 | } | |
2426 | ||
2427 | static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2428 | struct dlm_message *ms) | |
2429 | { | |
2430 | if (lkb->lkb_nodeid != ms->m_header.h_nodeid) { | |
2431 | log_error(ls, "convert_args nodeid %d %d lkid %x %x", | |
2432 | lkb->lkb_nodeid, ms->m_header.h_nodeid, | |
2433 | lkb->lkb_id, lkb->lkb_remid); | |
2434 | return -EINVAL; | |
2435 | } | |
2436 | ||
2437 | if (!is_master_copy(lkb)) | |
2438 | return -EINVAL; | |
2439 | ||
2440 | if (lkb->lkb_status != DLM_LKSTS_GRANTED) | |
2441 | return -EBUSY; | |
2442 | ||
e7fd4179 DT |
2443 | if (receive_lvb(ls, lkb, ms)) |
2444 | return -ENOMEM; | |
2445 | ||
2446 | lkb->lkb_rqmode = ms->m_rqmode; | |
2447 | lkb->lkb_lvbseq = ms->m_lvbseq; | |
2448 | ||
2449 | return 0; | |
2450 | } | |
2451 | ||
2452 | static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
2453 | struct dlm_message *ms) | |
2454 | { | |
2455 | if (!is_master_copy(lkb)) | |
2456 | return -EINVAL; | |
2457 | if (receive_lvb(ls, lkb, ms)) | |
2458 | return -ENOMEM; | |
2459 | return 0; | |
2460 | } | |
2461 | ||
2462 | /* We fill in the stub-lkb fields with the info that send_xxxx_reply() | |
2463 | uses to send a reply and that the remote end uses to process the reply. */ | |
2464 | ||
2465 | static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms) | |
2466 | { | |
2467 | struct dlm_lkb *lkb = &ls->ls_stub_lkb; | |
2468 | lkb->lkb_nodeid = ms->m_header.h_nodeid; | |
2469 | lkb->lkb_remid = ms->m_lkid; | |
2470 | } | |
2471 | ||
2472 | static void receive_request(struct dlm_ls *ls, struct dlm_message *ms) | |
2473 | { | |
2474 | struct dlm_lkb *lkb; | |
2475 | struct dlm_rsb *r; | |
2476 | int error, namelen; | |
2477 | ||
2478 | error = create_lkb(ls, &lkb); | |
2479 | if (error) | |
2480 | goto fail; | |
2481 | ||
2482 | receive_flags(lkb, ms); | |
2483 | lkb->lkb_flags |= DLM_IFL_MSTCPY; | |
2484 | error = receive_request_args(ls, lkb, ms); | |
2485 | if (error) { | |
b3f58d8f | 2486 | __put_lkb(ls, lkb); |
e7fd4179 DT |
2487 | goto fail; |
2488 | } | |
2489 | ||
2490 | namelen = receive_extralen(ms); | |
2491 | ||
2492 | error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r); | |
2493 | if (error) { | |
b3f58d8f | 2494 | __put_lkb(ls, lkb); |
e7fd4179 DT |
2495 | goto fail; |
2496 | } | |
2497 | ||
2498 | lock_rsb(r); | |
2499 | ||
2500 | attach_lkb(r, lkb); | |
2501 | error = do_request(r, lkb); | |
2502 | send_request_reply(r, lkb, error); | |
2503 | ||
2504 | unlock_rsb(r); | |
2505 | put_rsb(r); | |
2506 | ||
2507 | if (error == -EINPROGRESS) | |
2508 | error = 0; | |
2509 | if (error) | |
b3f58d8f | 2510 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2511 | return; |
2512 | ||
2513 | fail: | |
2514 | setup_stub_lkb(ls, ms); | |
2515 | send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2516 | } | |
2517 | ||
2518 | static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms) | |
2519 | { | |
2520 | struct dlm_lkb *lkb; | |
2521 | struct dlm_rsb *r; | |
90135925 | 2522 | int error, reply = 1; |
e7fd4179 DT |
2523 | |
2524 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2525 | if (error) | |
2526 | goto fail; | |
2527 | ||
2528 | r = lkb->lkb_resource; | |
2529 | ||
2530 | hold_rsb(r); | |
2531 | lock_rsb(r); | |
2532 | ||
2533 | receive_flags(lkb, ms); | |
2534 | error = receive_convert_args(ls, lkb, ms); | |
2535 | if (error) | |
2536 | goto out; | |
2537 | reply = !down_conversion(lkb); | |
2538 | ||
2539 | error = do_convert(r, lkb); | |
2540 | out: | |
2541 | if (reply) | |
2542 | send_convert_reply(r, lkb, error); | |
2543 | ||
2544 | unlock_rsb(r); | |
2545 | put_rsb(r); | |
b3f58d8f | 2546 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2547 | return; |
2548 | ||
2549 | fail: | |
2550 | setup_stub_lkb(ls, ms); | |
2551 | send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2552 | } | |
2553 | ||
2554 | static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms) | |
2555 | { | |
2556 | struct dlm_lkb *lkb; | |
2557 | struct dlm_rsb *r; | |
2558 | int error; | |
2559 | ||
2560 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2561 | if (error) | |
2562 | goto fail; | |
2563 | ||
2564 | r = lkb->lkb_resource; | |
2565 | ||
2566 | hold_rsb(r); | |
2567 | lock_rsb(r); | |
2568 | ||
2569 | receive_flags(lkb, ms); | |
2570 | error = receive_unlock_args(ls, lkb, ms); | |
2571 | if (error) | |
2572 | goto out; | |
2573 | ||
2574 | error = do_unlock(r, lkb); | |
2575 | out: | |
2576 | send_unlock_reply(r, lkb, error); | |
2577 | ||
2578 | unlock_rsb(r); | |
2579 | put_rsb(r); | |
b3f58d8f | 2580 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2581 | return; |
2582 | ||
2583 | fail: | |
2584 | setup_stub_lkb(ls, ms); | |
2585 | send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2586 | } | |
2587 | ||
2588 | static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms) | |
2589 | { | |
2590 | struct dlm_lkb *lkb; | |
2591 | struct dlm_rsb *r; | |
2592 | int error; | |
2593 | ||
2594 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2595 | if (error) | |
2596 | goto fail; | |
2597 | ||
2598 | receive_flags(lkb, ms); | |
2599 | ||
2600 | r = lkb->lkb_resource; | |
2601 | ||
2602 | hold_rsb(r); | |
2603 | lock_rsb(r); | |
2604 | ||
2605 | error = do_cancel(r, lkb); | |
2606 | send_cancel_reply(r, lkb, error); | |
2607 | ||
2608 | unlock_rsb(r); | |
2609 | put_rsb(r); | |
b3f58d8f | 2610 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2611 | return; |
2612 | ||
2613 | fail: | |
2614 | setup_stub_lkb(ls, ms); | |
2615 | send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); | |
2616 | } | |
2617 | ||
2618 | static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms) | |
2619 | { | |
2620 | struct dlm_lkb *lkb; | |
2621 | struct dlm_rsb *r; | |
2622 | int error; | |
2623 | ||
2624 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2625 | if (error) { | |
2626 | log_error(ls, "receive_grant no lkb"); | |
2627 | return; | |
2628 | } | |
2629 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2630 | ||
2631 | r = lkb->lkb_resource; | |
2632 | ||
2633 | hold_rsb(r); | |
2634 | lock_rsb(r); | |
2635 | ||
2636 | receive_flags_reply(lkb, ms); | |
2637 | grant_lock_pc(r, lkb, ms); | |
2638 | queue_cast(r, lkb, 0); | |
2639 | ||
2640 | unlock_rsb(r); | |
2641 | put_rsb(r); | |
b3f58d8f | 2642 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2643 | } |
2644 | ||
2645 | static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms) | |
2646 | { | |
2647 | struct dlm_lkb *lkb; | |
2648 | struct dlm_rsb *r; | |
2649 | int error; | |
2650 | ||
2651 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2652 | if (error) { | |
2653 | log_error(ls, "receive_bast no lkb"); | |
2654 | return; | |
2655 | } | |
2656 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2657 | ||
2658 | r = lkb->lkb_resource; | |
2659 | ||
2660 | hold_rsb(r); | |
2661 | lock_rsb(r); | |
2662 | ||
2663 | queue_bast(r, lkb, ms->m_bastmode); | |
2664 | ||
2665 | unlock_rsb(r); | |
2666 | put_rsb(r); | |
b3f58d8f | 2667 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2668 | } |
2669 | ||
2670 | static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms) | |
2671 | { | |
2672 | int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid; | |
2673 | ||
2674 | from_nodeid = ms->m_header.h_nodeid; | |
2675 | our_nodeid = dlm_our_nodeid(); | |
2676 | ||
2677 | len = receive_extralen(ms); | |
2678 | ||
2679 | dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); | |
2680 | if (dir_nodeid != our_nodeid) { | |
2681 | log_error(ls, "lookup dir_nodeid %d from %d", | |
2682 | dir_nodeid, from_nodeid); | |
2683 | error = -EINVAL; | |
2684 | ret_nodeid = -1; | |
2685 | goto out; | |
2686 | } | |
2687 | ||
2688 | error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid); | |
2689 | ||
2690 | /* Optimization: we're master so treat lookup as a request */ | |
2691 | if (!error && ret_nodeid == our_nodeid) { | |
2692 | receive_request(ls, ms); | |
2693 | return; | |
2694 | } | |
2695 | out: | |
2696 | send_lookup_reply(ls, ms, ret_nodeid, error); | |
2697 | } | |
2698 | ||
2699 | static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms) | |
2700 | { | |
2701 | int len, dir_nodeid, from_nodeid; | |
2702 | ||
2703 | from_nodeid = ms->m_header.h_nodeid; | |
2704 | ||
2705 | len = receive_extralen(ms); | |
2706 | ||
2707 | dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); | |
2708 | if (dir_nodeid != dlm_our_nodeid()) { | |
2709 | log_error(ls, "remove dir entry dir_nodeid %d from %d", | |
2710 | dir_nodeid, from_nodeid); | |
2711 | return; | |
2712 | } | |
2713 | ||
2714 | dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len); | |
2715 | } | |
2716 | ||
2717 | static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2718 | { | |
2719 | struct dlm_lkb *lkb; | |
2720 | struct dlm_rsb *r; | |
2721 | int error, mstype; | |
2722 | ||
2723 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2724 | if (error) { | |
2725 | log_error(ls, "receive_request_reply no lkb"); | |
2726 | return; | |
2727 | } | |
2728 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2729 | ||
2730 | mstype = lkb->lkb_wait_type; | |
2731 | error = remove_from_waiters(lkb); | |
2732 | if (error) { | |
2733 | log_error(ls, "receive_request_reply not on waiters"); | |
2734 | goto out; | |
2735 | } | |
2736 | ||
2737 | /* this is the value returned from do_request() on the master */ | |
2738 | error = ms->m_result; | |
2739 | ||
2740 | r = lkb->lkb_resource; | |
2741 | hold_rsb(r); | |
2742 | lock_rsb(r); | |
2743 | ||
2744 | /* Optimization: the dir node was also the master, so it took our | |
2745 | lookup as a request and sent request reply instead of lookup reply */ | |
2746 | if (mstype == DLM_MSG_LOOKUP) { | |
2747 | r->res_nodeid = ms->m_header.h_nodeid; | |
2748 | lkb->lkb_nodeid = r->res_nodeid; | |
2749 | } | |
2750 | ||
2751 | switch (error) { | |
2752 | case -EAGAIN: | |
2753 | /* request would block (be queued) on remote master; | |
2754 | the unhold undoes the original ref from create_lkb() | |
2755 | so it leads to the lkb being freed */ | |
2756 | queue_cast(r, lkb, -EAGAIN); | |
2757 | confirm_master(r, -EAGAIN); | |
2758 | unhold_lkb(lkb); | |
2759 | break; | |
2760 | ||
2761 | case -EINPROGRESS: | |
2762 | case 0: | |
2763 | /* request was queued or granted on remote master */ | |
2764 | receive_flags_reply(lkb, ms); | |
2765 | lkb->lkb_remid = ms->m_lkid; | |
2766 | if (error) | |
2767 | add_lkb(r, lkb, DLM_LKSTS_WAITING); | |
2768 | else { | |
2769 | grant_lock_pc(r, lkb, ms); | |
2770 | queue_cast(r, lkb, 0); | |
2771 | } | |
2772 | confirm_master(r, error); | |
2773 | break; | |
2774 | ||
597d0cae | 2775 | case -EBADR: |
e7fd4179 DT |
2776 | case -ENOTBLK: |
2777 | /* find_rsb failed to find rsb or rsb wasn't master */ | |
2778 | r->res_nodeid = -1; | |
2779 | lkb->lkb_nodeid = -1; | |
2780 | _request_lock(r, lkb); | |
2781 | break; | |
2782 | ||
2783 | default: | |
2784 | log_error(ls, "receive_request_reply error %d", error); | |
2785 | } | |
2786 | ||
2787 | unlock_rsb(r); | |
2788 | put_rsb(r); | |
2789 | out: | |
b3f58d8f | 2790 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2791 | } |
2792 | ||
2793 | static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, | |
2794 | struct dlm_message *ms) | |
2795 | { | |
2796 | int error = ms->m_result; | |
2797 | ||
2798 | /* this is the value returned from do_convert() on the master */ | |
2799 | ||
2800 | switch (error) { | |
2801 | case -EAGAIN: | |
2802 | /* convert would block (be queued) on remote master */ | |
2803 | queue_cast(r, lkb, -EAGAIN); | |
2804 | break; | |
2805 | ||
2806 | case -EINPROGRESS: | |
2807 | /* convert was queued on remote master */ | |
2808 | del_lkb(r, lkb); | |
2809 | add_lkb(r, lkb, DLM_LKSTS_CONVERT); | |
2810 | break; | |
2811 | ||
2812 | case 0: | |
2813 | /* convert was granted on remote master */ | |
2814 | receive_flags_reply(lkb, ms); | |
2815 | grant_lock_pc(r, lkb, ms); | |
2816 | queue_cast(r, lkb, 0); | |
2817 | break; | |
2818 | ||
2819 | default: | |
2820 | log_error(r->res_ls, "receive_convert_reply error %d", error); | |
2821 | } | |
2822 | } | |
2823 | ||
2824 | static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2825 | { | |
2826 | struct dlm_rsb *r = lkb->lkb_resource; | |
2827 | ||
2828 | hold_rsb(r); | |
2829 | lock_rsb(r); | |
2830 | ||
2831 | __receive_convert_reply(r, lkb, ms); | |
2832 | ||
2833 | unlock_rsb(r); | |
2834 | put_rsb(r); | |
2835 | } | |
2836 | ||
2837 | static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2838 | { | |
2839 | struct dlm_lkb *lkb; | |
2840 | int error; | |
2841 | ||
2842 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2843 | if (error) { | |
2844 | log_error(ls, "receive_convert_reply no lkb"); | |
2845 | return; | |
2846 | } | |
2847 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2848 | ||
2849 | error = remove_from_waiters(lkb); | |
2850 | if (error) { | |
2851 | log_error(ls, "receive_convert_reply not on waiters"); | |
2852 | goto out; | |
2853 | } | |
2854 | ||
2855 | _receive_convert_reply(lkb, ms); | |
2856 | out: | |
b3f58d8f | 2857 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2858 | } |
2859 | ||
2860 | static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2861 | { | |
2862 | struct dlm_rsb *r = lkb->lkb_resource; | |
2863 | int error = ms->m_result; | |
2864 | ||
2865 | hold_rsb(r); | |
2866 | lock_rsb(r); | |
2867 | ||
2868 | /* this is the value returned from do_unlock() on the master */ | |
2869 | ||
2870 | switch (error) { | |
2871 | case -DLM_EUNLOCK: | |
2872 | receive_flags_reply(lkb, ms); | |
2873 | remove_lock_pc(r, lkb); | |
2874 | queue_cast(r, lkb, -DLM_EUNLOCK); | |
2875 | break; | |
2876 | default: | |
2877 | log_error(r->res_ls, "receive_unlock_reply error %d", error); | |
2878 | } | |
2879 | ||
2880 | unlock_rsb(r); | |
2881 | put_rsb(r); | |
2882 | } | |
2883 | ||
2884 | static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2885 | { | |
2886 | struct dlm_lkb *lkb; | |
2887 | int error; | |
2888 | ||
2889 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2890 | if (error) { | |
2891 | log_error(ls, "receive_unlock_reply no lkb"); | |
2892 | return; | |
2893 | } | |
2894 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2895 | ||
2896 | error = remove_from_waiters(lkb); | |
2897 | if (error) { | |
2898 | log_error(ls, "receive_unlock_reply not on waiters"); | |
2899 | goto out; | |
2900 | } | |
2901 | ||
2902 | _receive_unlock_reply(lkb, ms); | |
2903 | out: | |
b3f58d8f | 2904 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2905 | } |
2906 | ||
2907 | static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms) | |
2908 | { | |
2909 | struct dlm_rsb *r = lkb->lkb_resource; | |
2910 | int error = ms->m_result; | |
2911 | ||
2912 | hold_rsb(r); | |
2913 | lock_rsb(r); | |
2914 | ||
2915 | /* this is the value returned from do_cancel() on the master */ | |
2916 | ||
2917 | switch (error) { | |
2918 | case -DLM_ECANCEL: | |
2919 | receive_flags_reply(lkb, ms); | |
2920 | revert_lock_pc(r, lkb); | |
2921 | queue_cast(r, lkb, -DLM_ECANCEL); | |
2922 | break; | |
2923 | default: | |
2924 | log_error(r->res_ls, "receive_cancel_reply error %d", error); | |
2925 | } | |
2926 | ||
2927 | unlock_rsb(r); | |
2928 | put_rsb(r); | |
2929 | } | |
2930 | ||
2931 | static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2932 | { | |
2933 | struct dlm_lkb *lkb; | |
2934 | int error; | |
2935 | ||
2936 | error = find_lkb(ls, ms->m_remid, &lkb); | |
2937 | if (error) { | |
2938 | log_error(ls, "receive_cancel_reply no lkb"); | |
2939 | return; | |
2940 | } | |
2941 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
2942 | ||
2943 | error = remove_from_waiters(lkb); | |
2944 | if (error) { | |
2945 | log_error(ls, "receive_cancel_reply not on waiters"); | |
2946 | goto out; | |
2947 | } | |
2948 | ||
2949 | _receive_cancel_reply(lkb, ms); | |
2950 | out: | |
b3f58d8f | 2951 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2952 | } |
2953 | ||
2954 | static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms) | |
2955 | { | |
2956 | struct dlm_lkb *lkb; | |
2957 | struct dlm_rsb *r; | |
2958 | int error, ret_nodeid; | |
2959 | ||
2960 | error = find_lkb(ls, ms->m_lkid, &lkb); | |
2961 | if (error) { | |
2962 | log_error(ls, "receive_lookup_reply no lkb"); | |
2963 | return; | |
2964 | } | |
2965 | ||
2966 | error = remove_from_waiters(lkb); | |
2967 | if (error) { | |
2968 | log_error(ls, "receive_lookup_reply not on waiters"); | |
2969 | goto out; | |
2970 | } | |
2971 | ||
2972 | /* this is the value returned by dlm_dir_lookup on dir node | |
2973 | FIXME: will a non-zero error ever be returned? */ | |
2974 | error = ms->m_result; | |
2975 | ||
2976 | r = lkb->lkb_resource; | |
2977 | hold_rsb(r); | |
2978 | lock_rsb(r); | |
2979 | ||
2980 | ret_nodeid = ms->m_nodeid; | |
2981 | if (ret_nodeid == dlm_our_nodeid()) { | |
2982 | r->res_nodeid = 0; | |
2983 | ret_nodeid = 0; | |
2984 | r->res_first_lkid = 0; | |
2985 | } else { | |
2986 | /* set_master() will copy res_nodeid to lkb_nodeid */ | |
2987 | r->res_nodeid = ret_nodeid; | |
2988 | } | |
2989 | ||
2990 | _request_lock(r, lkb); | |
2991 | ||
2992 | if (!ret_nodeid) | |
2993 | process_lookup_list(r); | |
2994 | ||
2995 | unlock_rsb(r); | |
2996 | put_rsb(r); | |
2997 | out: | |
b3f58d8f | 2998 | dlm_put_lkb(lkb); |
e7fd4179 DT |
2999 | } |
3000 | ||
3001 | int dlm_receive_message(struct dlm_header *hd, int nodeid, int recovery) | |
3002 | { | |
3003 | struct dlm_message *ms = (struct dlm_message *) hd; | |
3004 | struct dlm_ls *ls; | |
3005 | int error; | |
3006 | ||
3007 | if (!recovery) | |
3008 | dlm_message_in(ms); | |
3009 | ||
3010 | ls = dlm_find_lockspace_global(hd->h_lockspace); | |
3011 | if (!ls) { | |
3012 | log_print("drop message %d from %d for unknown lockspace %d", | |
3013 | ms->m_type, nodeid, hd->h_lockspace); | |
3014 | return -EINVAL; | |
3015 | } | |
3016 | ||
3017 | /* recovery may have just ended leaving a bunch of backed-up requests | |
3018 | in the requestqueue; wait while dlm_recoverd clears them */ | |
3019 | ||
3020 | if (!recovery) | |
3021 | dlm_wait_requestqueue(ls); | |
3022 | ||
3023 | /* recovery may have just started while there were a bunch of | |
3024 | in-flight requests -- save them in requestqueue to be processed | |
3025 | after recovery. we can't let dlm_recvd block on the recovery | |
3026 | lock. if dlm_recoverd is calling this function to clear the | |
3027 | requestqueue, it needs to be interrupted (-EINTR) if another | |
3028 | recovery operation is starting. */ | |
3029 | ||
3030 | while (1) { | |
3031 | if (dlm_locking_stopped(ls)) { | |
3032 | if (!recovery) | |
3033 | dlm_add_requestqueue(ls, nodeid, hd); | |
3034 | error = -EINTR; | |
3035 | goto out; | |
3036 | } | |
3037 | ||
3038 | if (lock_recovery_try(ls)) | |
3039 | break; | |
3040 | schedule(); | |
3041 | } | |
3042 | ||
3043 | switch (ms->m_type) { | |
3044 | ||
3045 | /* messages sent to a master node */ | |
3046 | ||
3047 | case DLM_MSG_REQUEST: | |
3048 | receive_request(ls, ms); | |
3049 | break; | |
3050 | ||
3051 | case DLM_MSG_CONVERT: | |
3052 | receive_convert(ls, ms); | |
3053 | break; | |
3054 | ||
3055 | case DLM_MSG_UNLOCK: | |
3056 | receive_unlock(ls, ms); | |
3057 | break; | |
3058 | ||
3059 | case DLM_MSG_CANCEL: | |
3060 | receive_cancel(ls, ms); | |
3061 | break; | |
3062 | ||
3063 | /* messages sent from a master node (replies to above) */ | |
3064 | ||
3065 | case DLM_MSG_REQUEST_REPLY: | |
3066 | receive_request_reply(ls, ms); | |
3067 | break; | |
3068 | ||
3069 | case DLM_MSG_CONVERT_REPLY: | |
3070 | receive_convert_reply(ls, ms); | |
3071 | break; | |
3072 | ||
3073 | case DLM_MSG_UNLOCK_REPLY: | |
3074 | receive_unlock_reply(ls, ms); | |
3075 | break; | |
3076 | ||
3077 | case DLM_MSG_CANCEL_REPLY: | |
3078 | receive_cancel_reply(ls, ms); | |
3079 | break; | |
3080 | ||
3081 | /* messages sent from a master node (only two types of async msg) */ | |
3082 | ||
3083 | case DLM_MSG_GRANT: | |
3084 | receive_grant(ls, ms); | |
3085 | break; | |
3086 | ||
3087 | case DLM_MSG_BAST: | |
3088 | receive_bast(ls, ms); | |
3089 | break; | |
3090 | ||
3091 | /* messages sent to a dir node */ | |
3092 | ||
3093 | case DLM_MSG_LOOKUP: | |
3094 | receive_lookup(ls, ms); | |
3095 | break; | |
3096 | ||
3097 | case DLM_MSG_REMOVE: | |
3098 | receive_remove(ls, ms); | |
3099 | break; | |
3100 | ||
3101 | /* messages sent from a dir node (remove has no reply) */ | |
3102 | ||
3103 | case DLM_MSG_LOOKUP_REPLY: | |
3104 | receive_lookup_reply(ls, ms); | |
3105 | break; | |
3106 | ||
3107 | default: | |
3108 | log_error(ls, "unknown message type %d", ms->m_type); | |
3109 | } | |
3110 | ||
3111 | unlock_recovery(ls); | |
3112 | out: | |
3113 | dlm_put_lockspace(ls); | |
3114 | dlm_astd_wake(); | |
3115 | return 0; | |
3116 | } | |
3117 | ||
3118 | ||
3119 | /* | |
3120 | * Recovery related | |
3121 | */ | |
3122 | ||
3123 | static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3124 | { | |
3125 | if (middle_conversion(lkb)) { | |
3126 | hold_lkb(lkb); | |
3127 | ls->ls_stub_ms.m_result = -EINPROGRESS; | |
3128 | _remove_from_waiters(lkb); | |
3129 | _receive_convert_reply(lkb, &ls->ls_stub_ms); | |
3130 | ||
3131 | /* Same special case as in receive_rcom_lock_args() */ | |
3132 | lkb->lkb_grmode = DLM_LOCK_IV; | |
3133 | rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT); | |
3134 | unhold_lkb(lkb); | |
3135 | ||
3136 | } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) { | |
3137 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3138 | } | |
3139 | ||
3140 | /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down | |
3141 | conversions are async; there's no reply from the remote master */ | |
3142 | } | |
3143 | ||
3144 | /* A waiting lkb needs recovery if the master node has failed, or | |
3145 | the master node is changing (only when no directory is used) */ | |
3146 | ||
3147 | static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3148 | { | |
3149 | if (dlm_is_removed(ls, lkb->lkb_nodeid)) | |
3150 | return 1; | |
3151 | ||
3152 | if (!dlm_no_directory(ls)) | |
3153 | return 0; | |
3154 | ||
3155 | if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid) | |
3156 | return 1; | |
3157 | ||
3158 | return 0; | |
3159 | } | |
3160 | ||
3161 | /* Recovery for locks that are waiting for replies from nodes that are now | |
3162 | gone. We can just complete unlocks and cancels by faking a reply from the | |
3163 | dead node. Requests and up-conversions we flag to be resent after | |
3164 | recovery. Down-conversions can just be completed with a fake reply like | |
3165 | unlocks. Conversions between PR and CW need special attention. */ | |
3166 | ||
3167 | void dlm_recover_waiters_pre(struct dlm_ls *ls) | |
3168 | { | |
3169 | struct dlm_lkb *lkb, *safe; | |
3170 | ||
90135925 | 3171 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3172 | |
3173 | list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) { | |
3174 | log_debug(ls, "pre recover waiter lkid %x type %d flags %x", | |
3175 | lkb->lkb_id, lkb->lkb_wait_type, lkb->lkb_flags); | |
3176 | ||
3177 | /* all outstanding lookups, regardless of destination will be | |
3178 | resent after recovery is done */ | |
3179 | ||
3180 | if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) { | |
3181 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3182 | continue; | |
3183 | } | |
3184 | ||
3185 | if (!waiter_needs_recovery(ls, lkb)) | |
3186 | continue; | |
3187 | ||
3188 | switch (lkb->lkb_wait_type) { | |
3189 | ||
3190 | case DLM_MSG_REQUEST: | |
3191 | lkb->lkb_flags |= DLM_IFL_RESEND; | |
3192 | break; | |
3193 | ||
3194 | case DLM_MSG_CONVERT: | |
3195 | recover_convert_waiter(ls, lkb); | |
3196 | break; | |
3197 | ||
3198 | case DLM_MSG_UNLOCK: | |
3199 | hold_lkb(lkb); | |
3200 | ls->ls_stub_ms.m_result = -DLM_EUNLOCK; | |
3201 | _remove_from_waiters(lkb); | |
3202 | _receive_unlock_reply(lkb, &ls->ls_stub_ms); | |
b3f58d8f | 3203 | dlm_put_lkb(lkb); |
e7fd4179 DT |
3204 | break; |
3205 | ||
3206 | case DLM_MSG_CANCEL: | |
3207 | hold_lkb(lkb); | |
3208 | ls->ls_stub_ms.m_result = -DLM_ECANCEL; | |
3209 | _remove_from_waiters(lkb); | |
3210 | _receive_cancel_reply(lkb, &ls->ls_stub_ms); | |
b3f58d8f | 3211 | dlm_put_lkb(lkb); |
e7fd4179 DT |
3212 | break; |
3213 | ||
3214 | default: | |
3215 | log_error(ls, "invalid lkb wait_type %d", | |
3216 | lkb->lkb_wait_type); | |
3217 | } | |
81456807 | 3218 | schedule(); |
e7fd4179 | 3219 | } |
90135925 | 3220 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3221 | } |
3222 | ||
3223 | static int remove_resend_waiter(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) | |
3224 | { | |
3225 | struct dlm_lkb *lkb; | |
3226 | int rv = 0; | |
3227 | ||
90135925 | 3228 | mutex_lock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3229 | list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) { |
3230 | if (lkb->lkb_flags & DLM_IFL_RESEND) { | |
3231 | rv = lkb->lkb_wait_type; | |
3232 | _remove_from_waiters(lkb); | |
3233 | lkb->lkb_flags &= ~DLM_IFL_RESEND; | |
3234 | break; | |
3235 | } | |
3236 | } | |
90135925 | 3237 | mutex_unlock(&ls->ls_waiters_mutex); |
e7fd4179 DT |
3238 | |
3239 | if (!rv) | |
3240 | lkb = NULL; | |
3241 | *lkb_ret = lkb; | |
3242 | return rv; | |
3243 | } | |
3244 | ||
3245 | /* Deal with lookups and lkb's marked RESEND from _pre. We may now be the | |
3246 | master or dir-node for r. Processing the lkb may result in it being placed | |
3247 | back on waiters. */ | |
3248 | ||
3249 | int dlm_recover_waiters_post(struct dlm_ls *ls) | |
3250 | { | |
3251 | struct dlm_lkb *lkb; | |
3252 | struct dlm_rsb *r; | |
3253 | int error = 0, mstype; | |
3254 | ||
3255 | while (1) { | |
3256 | if (dlm_locking_stopped(ls)) { | |
3257 | log_debug(ls, "recover_waiters_post aborted"); | |
3258 | error = -EINTR; | |
3259 | break; | |
3260 | } | |
3261 | ||
3262 | mstype = remove_resend_waiter(ls, &lkb); | |
3263 | if (!mstype) | |
3264 | break; | |
3265 | ||
3266 | r = lkb->lkb_resource; | |
3267 | ||
3268 | log_debug(ls, "recover_waiters_post %x type %d flags %x %s", | |
3269 | lkb->lkb_id, mstype, lkb->lkb_flags, r->res_name); | |
3270 | ||
3271 | switch (mstype) { | |
3272 | ||
3273 | case DLM_MSG_LOOKUP: | |
3274 | hold_rsb(r); | |
3275 | lock_rsb(r); | |
3276 | _request_lock(r, lkb); | |
3277 | if (is_master(r)) | |
3278 | confirm_master(r, 0); | |
3279 | unlock_rsb(r); | |
3280 | put_rsb(r); | |
3281 | break; | |
3282 | ||
3283 | case DLM_MSG_REQUEST: | |
3284 | hold_rsb(r); | |
3285 | lock_rsb(r); | |
3286 | _request_lock(r, lkb); | |
3287 | unlock_rsb(r); | |
3288 | put_rsb(r); | |
3289 | break; | |
3290 | ||
3291 | case DLM_MSG_CONVERT: | |
3292 | hold_rsb(r); | |
3293 | lock_rsb(r); | |
3294 | _convert_lock(r, lkb); | |
3295 | unlock_rsb(r); | |
3296 | put_rsb(r); | |
3297 | break; | |
3298 | ||
3299 | default: | |
3300 | log_error(ls, "recover_waiters_post type %d", mstype); | |
3301 | } | |
3302 | } | |
3303 | ||
3304 | return error; | |
3305 | } | |
3306 | ||
3307 | static void purge_queue(struct dlm_rsb *r, struct list_head *queue, | |
3308 | int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb)) | |
3309 | { | |
3310 | struct dlm_ls *ls = r->res_ls; | |
3311 | struct dlm_lkb *lkb, *safe; | |
3312 | ||
3313 | list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) { | |
3314 | if (test(ls, lkb)) { | |
97a35d1e | 3315 | rsb_set_flag(r, RSB_LOCKS_PURGED); |
e7fd4179 DT |
3316 | del_lkb(r, lkb); |
3317 | /* this put should free the lkb */ | |
b3f58d8f | 3318 | if (!dlm_put_lkb(lkb)) |
e7fd4179 DT |
3319 | log_error(ls, "purged lkb not released"); |
3320 | } | |
3321 | } | |
3322 | } | |
3323 | ||
3324 | static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3325 | { | |
3326 | return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid)); | |
3327 | } | |
3328 | ||
3329 | static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3330 | { | |
3331 | return is_master_copy(lkb); | |
3332 | } | |
3333 | ||
3334 | static void purge_dead_locks(struct dlm_rsb *r) | |
3335 | { | |
3336 | purge_queue(r, &r->res_grantqueue, &purge_dead_test); | |
3337 | purge_queue(r, &r->res_convertqueue, &purge_dead_test); | |
3338 | purge_queue(r, &r->res_waitqueue, &purge_dead_test); | |
3339 | } | |
3340 | ||
3341 | void dlm_purge_mstcpy_locks(struct dlm_rsb *r) | |
3342 | { | |
3343 | purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test); | |
3344 | purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test); | |
3345 | purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test); | |
3346 | } | |
3347 | ||
3348 | /* Get rid of locks held by nodes that are gone. */ | |
3349 | ||
3350 | int dlm_purge_locks(struct dlm_ls *ls) | |
3351 | { | |
3352 | struct dlm_rsb *r; | |
3353 | ||
3354 | log_debug(ls, "dlm_purge_locks"); | |
3355 | ||
3356 | down_write(&ls->ls_root_sem); | |
3357 | list_for_each_entry(r, &ls->ls_root_list, res_root_list) { | |
3358 | hold_rsb(r); | |
3359 | lock_rsb(r); | |
3360 | if (is_master(r)) | |
3361 | purge_dead_locks(r); | |
3362 | unlock_rsb(r); | |
3363 | unhold_rsb(r); | |
3364 | ||
3365 | schedule(); | |
3366 | } | |
3367 | up_write(&ls->ls_root_sem); | |
3368 | ||
3369 | return 0; | |
3370 | } | |
3371 | ||
97a35d1e DT |
3372 | static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket) |
3373 | { | |
3374 | struct dlm_rsb *r, *r_ret = NULL; | |
3375 | ||
3376 | read_lock(&ls->ls_rsbtbl[bucket].lock); | |
3377 | list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list, res_hashchain) { | |
3378 | if (!rsb_flag(r, RSB_LOCKS_PURGED)) | |
3379 | continue; | |
3380 | hold_rsb(r); | |
3381 | rsb_clear_flag(r, RSB_LOCKS_PURGED); | |
3382 | r_ret = r; | |
3383 | break; | |
3384 | } | |
3385 | read_unlock(&ls->ls_rsbtbl[bucket].lock); | |
3386 | return r_ret; | |
3387 | } | |
3388 | ||
3389 | void dlm_grant_after_purge(struct dlm_ls *ls) | |
e7fd4179 DT |
3390 | { |
3391 | struct dlm_rsb *r; | |
2b4e926a | 3392 | int bucket = 0; |
e7fd4179 | 3393 | |
2b4e926a DT |
3394 | while (1) { |
3395 | r = find_purged_rsb(ls, bucket); | |
3396 | if (!r) { | |
3397 | if (bucket == ls->ls_rsbtbl_size - 1) | |
3398 | break; | |
3399 | bucket++; | |
97a35d1e | 3400 | continue; |
2b4e926a | 3401 | } |
97a35d1e DT |
3402 | lock_rsb(r); |
3403 | if (is_master(r)) { | |
3404 | grant_pending_locks(r); | |
3405 | confirm_master(r, 0); | |
e7fd4179 | 3406 | } |
97a35d1e DT |
3407 | unlock_rsb(r); |
3408 | put_rsb(r); | |
2b4e926a | 3409 | schedule(); |
e7fd4179 | 3410 | } |
e7fd4179 DT |
3411 | } |
3412 | ||
3413 | static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid, | |
3414 | uint32_t remid) | |
3415 | { | |
3416 | struct dlm_lkb *lkb; | |
3417 | ||
3418 | list_for_each_entry(lkb, head, lkb_statequeue) { | |
3419 | if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid) | |
3420 | return lkb; | |
3421 | } | |
3422 | return NULL; | |
3423 | } | |
3424 | ||
3425 | static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid, | |
3426 | uint32_t remid) | |
3427 | { | |
3428 | struct dlm_lkb *lkb; | |
3429 | ||
3430 | lkb = search_remid_list(&r->res_grantqueue, nodeid, remid); | |
3431 | if (lkb) | |
3432 | return lkb; | |
3433 | lkb = search_remid_list(&r->res_convertqueue, nodeid, remid); | |
3434 | if (lkb) | |
3435 | return lkb; | |
3436 | lkb = search_remid_list(&r->res_waitqueue, nodeid, remid); | |
3437 | if (lkb) | |
3438 | return lkb; | |
3439 | return NULL; | |
3440 | } | |
3441 | ||
3442 | static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, | |
3443 | struct dlm_rsb *r, struct dlm_rcom *rc) | |
3444 | { | |
3445 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3446 | int lvblen; | |
3447 | ||
3448 | lkb->lkb_nodeid = rc->rc_header.h_nodeid; | |
3449 | lkb->lkb_ownpid = rl->rl_ownpid; | |
3450 | lkb->lkb_remid = rl->rl_lkid; | |
3451 | lkb->lkb_exflags = rl->rl_exflags; | |
3452 | lkb->lkb_flags = rl->rl_flags & 0x0000FFFF; | |
3453 | lkb->lkb_flags |= DLM_IFL_MSTCPY; | |
3454 | lkb->lkb_lvbseq = rl->rl_lvbseq; | |
3455 | lkb->lkb_rqmode = rl->rl_rqmode; | |
3456 | lkb->lkb_grmode = rl->rl_grmode; | |
3457 | /* don't set lkb_status because add_lkb wants to itself */ | |
3458 | ||
3459 | lkb->lkb_bastaddr = (void *) (long) (rl->rl_asts & AST_BAST); | |
3460 | lkb->lkb_astaddr = (void *) (long) (rl->rl_asts & AST_COMP); | |
3461 | ||
e7fd4179 DT |
3462 | if (lkb->lkb_exflags & DLM_LKF_VALBLK) { |
3463 | lkb->lkb_lvbptr = allocate_lvb(ls); | |
3464 | if (!lkb->lkb_lvbptr) | |
3465 | return -ENOMEM; | |
3466 | lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) - | |
3467 | sizeof(struct rcom_lock); | |
3468 | memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen); | |
3469 | } | |
3470 | ||
3471 | /* Conversions between PR and CW (middle modes) need special handling. | |
3472 | The real granted mode of these converting locks cannot be determined | |
3473 | until all locks have been rebuilt on the rsb (recover_conversion) */ | |
3474 | ||
3475 | if (rl->rl_wait_type == DLM_MSG_CONVERT && middle_conversion(lkb)) { | |
3476 | rl->rl_status = DLM_LKSTS_CONVERT; | |
3477 | lkb->lkb_grmode = DLM_LOCK_IV; | |
3478 | rsb_set_flag(r, RSB_RECOVER_CONVERT); | |
3479 | } | |
3480 | ||
3481 | return 0; | |
3482 | } | |
3483 | ||
3484 | /* This lkb may have been recovered in a previous aborted recovery so we need | |
3485 | to check if the rsb already has an lkb with the given remote nodeid/lkid. | |
3486 | If so we just send back a standard reply. If not, we create a new lkb with | |
3487 | the given values and send back our lkid. We send back our lkid by sending | |
3488 | back the rcom_lock struct we got but with the remid field filled in. */ | |
3489 | ||
3490 | int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc) | |
3491 | { | |
3492 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3493 | struct dlm_rsb *r; | |
3494 | struct dlm_lkb *lkb; | |
3495 | int error; | |
3496 | ||
3497 | if (rl->rl_parent_lkid) { | |
3498 | error = -EOPNOTSUPP; | |
3499 | goto out; | |
3500 | } | |
3501 | ||
3502 | error = find_rsb(ls, rl->rl_name, rl->rl_namelen, R_MASTER, &r); | |
3503 | if (error) | |
3504 | goto out; | |
3505 | ||
3506 | lock_rsb(r); | |
3507 | ||
3508 | lkb = search_remid(r, rc->rc_header.h_nodeid, rl->rl_lkid); | |
3509 | if (lkb) { | |
3510 | error = -EEXIST; | |
3511 | goto out_remid; | |
3512 | } | |
3513 | ||
3514 | error = create_lkb(ls, &lkb); | |
3515 | if (error) | |
3516 | goto out_unlock; | |
3517 | ||
3518 | error = receive_rcom_lock_args(ls, lkb, r, rc); | |
3519 | if (error) { | |
b3f58d8f | 3520 | __put_lkb(ls, lkb); |
e7fd4179 DT |
3521 | goto out_unlock; |
3522 | } | |
3523 | ||
3524 | attach_lkb(r, lkb); | |
3525 | add_lkb(r, lkb, rl->rl_status); | |
3526 | error = 0; | |
3527 | ||
3528 | out_remid: | |
3529 | /* this is the new value returned to the lock holder for | |
3530 | saving in its process-copy lkb */ | |
3531 | rl->rl_remid = lkb->lkb_id; | |
3532 | ||
3533 | out_unlock: | |
3534 | unlock_rsb(r); | |
3535 | put_rsb(r); | |
3536 | out: | |
3537 | if (error) | |
3538 | log_print("recover_master_copy %d %x", error, rl->rl_lkid); | |
3539 | rl->rl_result = error; | |
3540 | return error; | |
3541 | } | |
3542 | ||
3543 | int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc) | |
3544 | { | |
3545 | struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; | |
3546 | struct dlm_rsb *r; | |
3547 | struct dlm_lkb *lkb; | |
3548 | int error; | |
3549 | ||
3550 | error = find_lkb(ls, rl->rl_lkid, &lkb); | |
3551 | if (error) { | |
3552 | log_error(ls, "recover_process_copy no lkid %x", rl->rl_lkid); | |
3553 | return error; | |
3554 | } | |
3555 | ||
3556 | DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); | |
3557 | ||
3558 | error = rl->rl_result; | |
3559 | ||
3560 | r = lkb->lkb_resource; | |
3561 | hold_rsb(r); | |
3562 | lock_rsb(r); | |
3563 | ||
3564 | switch (error) { | |
3565 | case -EEXIST: | |
3566 | log_debug(ls, "master copy exists %x", lkb->lkb_id); | |
3567 | /* fall through */ | |
3568 | case 0: | |
3569 | lkb->lkb_remid = rl->rl_remid; | |
3570 | break; | |
3571 | default: | |
3572 | log_error(ls, "dlm_recover_process_copy unknown error %d %x", | |
3573 | error, lkb->lkb_id); | |
3574 | } | |
3575 | ||
3576 | /* an ack for dlm_recover_locks() which waits for replies from | |
3577 | all the locks it sends to new masters */ | |
3578 | dlm_recovered_lock(r); | |
3579 | ||
3580 | unlock_rsb(r); | |
3581 | put_rsb(r); | |
b3f58d8f | 3582 | dlm_put_lkb(lkb); |
e7fd4179 DT |
3583 | |
3584 | return 0; | |
3585 | } | |
3586 | ||
597d0cae DT |
3587 | int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua, |
3588 | int mode, uint32_t flags, void *name, unsigned int namelen, | |
3589 | uint32_t parent_lkid) | |
3590 | { | |
3591 | struct dlm_lkb *lkb; | |
3592 | struct dlm_args args; | |
3593 | int error; | |
3594 | ||
3595 | lock_recovery(ls); | |
3596 | ||
3597 | error = create_lkb(ls, &lkb); | |
3598 | if (error) { | |
3599 | kfree(ua); | |
3600 | goto out; | |
3601 | } | |
3602 | ||
3603 | if (flags & DLM_LKF_VALBLK) { | |
3604 | ua->lksb.sb_lvbptr = kmalloc(DLM_USER_LVB_LEN, GFP_KERNEL); | |
3605 | if (!ua->lksb.sb_lvbptr) { | |
3606 | kfree(ua); | |
3607 | __put_lkb(ls, lkb); | |
3608 | error = -ENOMEM; | |
3609 | goto out; | |
3610 | } | |
3611 | } | |
3612 | ||
3613 | /* After ua is attached to lkb it will be freed by free_lkb(). | |
3614 | When DLM_IFL_USER is set, the dlm knows that this is a userspace | |
3615 | lock and that lkb_astparam is the dlm_user_args structure. */ | |
3616 | ||
3617 | error = set_lock_args(mode, &ua->lksb, flags, namelen, parent_lkid, | |
3618 | FAKE_USER_AST, ua, FAKE_USER_AST, &args); | |
3619 | lkb->lkb_flags |= DLM_IFL_USER; | |
3620 | ua->old_mode = DLM_LOCK_IV; | |
3621 | ||
3622 | if (error) { | |
3623 | __put_lkb(ls, lkb); | |
3624 | goto out; | |
3625 | } | |
3626 | ||
3627 | error = request_lock(ls, lkb, name, namelen, &args); | |
3628 | ||
3629 | switch (error) { | |
3630 | case 0: | |
3631 | break; | |
3632 | case -EINPROGRESS: | |
3633 | error = 0; | |
3634 | break; | |
3635 | case -EAGAIN: | |
3636 | error = 0; | |
3637 | /* fall through */ | |
3638 | default: | |
3639 | __put_lkb(ls, lkb); | |
3640 | goto out; | |
3641 | } | |
3642 | ||
3643 | /* add this new lkb to the per-process list of locks */ | |
3644 | spin_lock(&ua->proc->locks_spin); | |
3645 | kref_get(&lkb->lkb_ref); | |
3646 | list_add_tail(&lkb->lkb_ownqueue, &ua->proc->locks); | |
3647 | spin_unlock(&ua->proc->locks_spin); | |
3648 | out: | |
3649 | unlock_recovery(ls); | |
3650 | return error; | |
3651 | } | |
3652 | ||
3653 | int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp, | |
3654 | int mode, uint32_t flags, uint32_t lkid, char *lvb_in) | |
3655 | { | |
3656 | struct dlm_lkb *lkb; | |
3657 | struct dlm_args args; | |
3658 | struct dlm_user_args *ua; | |
3659 | int error; | |
3660 | ||
3661 | lock_recovery(ls); | |
3662 | ||
3663 | error = find_lkb(ls, lkid, &lkb); | |
3664 | if (error) | |
3665 | goto out; | |
3666 | ||
3667 | /* user can change the params on its lock when it converts it, or | |
3668 | add an lvb that didn't exist before */ | |
3669 | ||
3670 | ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
3671 | ||
3672 | if (flags & DLM_LKF_VALBLK && !ua->lksb.sb_lvbptr) { | |
3673 | ua->lksb.sb_lvbptr = kmalloc(DLM_USER_LVB_LEN, GFP_KERNEL); | |
3674 | if (!ua->lksb.sb_lvbptr) { | |
3675 | error = -ENOMEM; | |
3676 | goto out_put; | |
3677 | } | |
3678 | } | |
3679 | if (lvb_in && ua->lksb.sb_lvbptr) | |
3680 | memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN); | |
3681 | ||
3682 | ua->castparam = ua_tmp->castparam; | |
3683 | ua->castaddr = ua_tmp->castaddr; | |
3684 | ua->bastparam = ua_tmp->bastparam; | |
3685 | ua->bastaddr = ua_tmp->bastaddr; | |
10948eb4 | 3686 | ua->user_lksb = ua_tmp->user_lksb; |
597d0cae DT |
3687 | ua->old_mode = lkb->lkb_grmode; |
3688 | ||
3689 | error = set_lock_args(mode, &ua->lksb, flags, 0, 0, FAKE_USER_AST, ua, | |
3690 | FAKE_USER_AST, &args); | |
3691 | if (error) | |
3692 | goto out_put; | |
3693 | ||
3694 | error = convert_lock(ls, lkb, &args); | |
3695 | ||
3696 | if (error == -EINPROGRESS || error == -EAGAIN) | |
3697 | error = 0; | |
3698 | out_put: | |
3699 | dlm_put_lkb(lkb); | |
3700 | out: | |
3701 | unlock_recovery(ls); | |
3702 | kfree(ua_tmp); | |
3703 | return error; | |
3704 | } | |
3705 | ||
3706 | int dlm_user_unlock(struct dlm_ls *ls, struct dlm_user_args *ua_tmp, | |
3707 | uint32_t flags, uint32_t lkid, char *lvb_in) | |
3708 | { | |
3709 | struct dlm_lkb *lkb; | |
3710 | struct dlm_args args; | |
3711 | struct dlm_user_args *ua; | |
3712 | int error; | |
3713 | ||
3714 | lock_recovery(ls); | |
3715 | ||
3716 | error = find_lkb(ls, lkid, &lkb); | |
3717 | if (error) | |
3718 | goto out; | |
3719 | ||
3720 | ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
3721 | ||
3722 | if (lvb_in && ua->lksb.sb_lvbptr) | |
3723 | memcpy(ua->lksb.sb_lvbptr, lvb_in, DLM_USER_LVB_LEN); | |
3724 | ua->castparam = ua_tmp->castparam; | |
cc346d55 | 3725 | ua->user_lksb = ua_tmp->user_lksb; |
597d0cae DT |
3726 | |
3727 | error = set_unlock_args(flags, ua, &args); | |
3728 | if (error) | |
3729 | goto out_put; | |
3730 | ||
3731 | error = unlock_lock(ls, lkb, &args); | |
3732 | ||
3733 | if (error == -DLM_EUNLOCK) | |
3734 | error = 0; | |
3735 | if (error) | |
3736 | goto out_put; | |
3737 | ||
3738 | spin_lock(&ua->proc->locks_spin); | |
34e22bed | 3739 | list_del_init(&lkb->lkb_ownqueue); |
597d0cae DT |
3740 | spin_unlock(&ua->proc->locks_spin); |
3741 | ||
3742 | /* this removes the reference for the proc->locks list added by | |
3743 | dlm_user_request */ | |
3744 | unhold_lkb(lkb); | |
3745 | out_put: | |
3746 | dlm_put_lkb(lkb); | |
3747 | out: | |
3748 | unlock_recovery(ls); | |
3749 | return error; | |
3750 | } | |
3751 | ||
3752 | int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp, | |
3753 | uint32_t flags, uint32_t lkid) | |
3754 | { | |
3755 | struct dlm_lkb *lkb; | |
3756 | struct dlm_args args; | |
3757 | struct dlm_user_args *ua; | |
3758 | int error; | |
3759 | ||
3760 | lock_recovery(ls); | |
3761 | ||
3762 | error = find_lkb(ls, lkid, &lkb); | |
3763 | if (error) | |
3764 | goto out; | |
3765 | ||
3766 | ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
3767 | ua->castparam = ua_tmp->castparam; | |
3768 | ||
3769 | error = set_unlock_args(flags, ua, &args); | |
3770 | if (error) | |
3771 | goto out_put; | |
3772 | ||
3773 | error = cancel_lock(ls, lkb, &args); | |
3774 | ||
3775 | if (error == -DLM_ECANCEL) | |
3776 | error = 0; | |
3777 | if (error) | |
3778 | goto out_put; | |
3779 | ||
3780 | /* this lkb was removed from the WAITING queue */ | |
3781 | if (lkb->lkb_grmode == DLM_LOCK_IV) { | |
3782 | spin_lock(&ua->proc->locks_spin); | |
34e22bed | 3783 | list_del_init(&lkb->lkb_ownqueue); |
597d0cae DT |
3784 | spin_unlock(&ua->proc->locks_spin); |
3785 | unhold_lkb(lkb); | |
3786 | } | |
3787 | out_put: | |
3788 | dlm_put_lkb(lkb); | |
3789 | out: | |
3790 | unlock_recovery(ls); | |
3791 | return error; | |
3792 | } | |
3793 | ||
3794 | static int orphan_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3795 | { | |
3796 | struct dlm_user_args *ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
3797 | ||
3798 | if (ua->lksb.sb_lvbptr) | |
3799 | kfree(ua->lksb.sb_lvbptr); | |
3800 | kfree(ua); | |
3801 | lkb->lkb_astparam = (long)NULL; | |
3802 | ||
3803 | /* TODO: propogate to master if needed */ | |
3804 | return 0; | |
3805 | } | |
3806 | ||
3807 | /* The force flag allows the unlock to go ahead even if the lkb isn't granted. | |
3808 | Regardless of what rsb queue the lock is on, it's removed and freed. */ | |
3809 | ||
3810 | static int unlock_proc_lock(struct dlm_ls *ls, struct dlm_lkb *lkb) | |
3811 | { | |
3812 | struct dlm_user_args *ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
3813 | struct dlm_args args; | |
3814 | int error; | |
3815 | ||
3816 | /* FIXME: we need to handle the case where the lkb is in limbo | |
3817 | while the rsb is being looked up, currently we assert in | |
3818 | _unlock_lock/is_remote because rsb nodeid is -1. */ | |
3819 | ||
3820 | set_unlock_args(DLM_LKF_FORCEUNLOCK, ua, &args); | |
3821 | ||
3822 | error = unlock_lock(ls, lkb, &args); | |
3823 | if (error == -DLM_EUNLOCK) | |
3824 | error = 0; | |
3825 | return error; | |
3826 | } | |
3827 | ||
3828 | /* The ls_clear_proc_locks mutex protects against dlm_user_add_asts() which | |
3829 | 1) references lkb->ua which we free here and 2) adds lkbs to proc->asts, | |
3830 | which we clear here. */ | |
3831 | ||
3832 | /* proc CLOSING flag is set so no more device_reads should look at proc->asts | |
3833 | list, and no more device_writes should add lkb's to proc->locks list; so we | |
3834 | shouldn't need to take asts_spin or locks_spin here. this assumes that | |
3835 | device reads/writes/closes are serialized -- FIXME: we may need to serialize | |
3836 | them ourself. */ | |
3837 | ||
3838 | void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc) | |
3839 | { | |
3840 | struct dlm_lkb *lkb, *safe; | |
3841 | ||
3842 | lock_recovery(ls); | |
3843 | mutex_lock(&ls->ls_clear_proc_locks); | |
3844 | ||
3845 | list_for_each_entry_safe(lkb, safe, &proc->locks, lkb_ownqueue) { | |
3846 | if (lkb->lkb_ast_type) { | |
3847 | list_del(&lkb->lkb_astqueue); | |
3848 | unhold_lkb(lkb); | |
3849 | } | |
3850 | ||
34e22bed | 3851 | list_del_init(&lkb->lkb_ownqueue); |
597d0cae DT |
3852 | |
3853 | if (lkb->lkb_exflags & DLM_LKF_PERSISTENT) { | |
3854 | lkb->lkb_flags |= DLM_IFL_ORPHAN; | |
3855 | orphan_proc_lock(ls, lkb); | |
3856 | } else { | |
3857 | lkb->lkb_flags |= DLM_IFL_DEAD; | |
3858 | unlock_proc_lock(ls, lkb); | |
3859 | } | |
3860 | ||
3861 | /* this removes the reference for the proc->locks list | |
3862 | added by dlm_user_request, it may result in the lkb | |
3863 | being freed */ | |
3864 | ||
3865 | dlm_put_lkb(lkb); | |
3866 | } | |
3867 | mutex_unlock(&ls->ls_clear_proc_locks); | |
3868 | unlock_recovery(ls); | |
3869 | } |