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b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
3 | * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. | |
4 | * | |
5 | * This copyrighted material is made available to anyone wishing to use, | |
6 | * modify, copy, or redistribute it subject to the terms and conditions | |
7 | * of the GNU General Public License v.2. | |
8 | */ | |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/completion.h> | |
14 | #include <linux/buffer_head.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/sort.h> | |
17 | #include <linux/jhash.h> | |
18 | #include <linux/kref.h> | |
19 | #include <asm/semaphore.h> | |
20 | #include <asm/uaccess.h> | |
21 | ||
22 | #include "gfs2.h" | |
23 | #include "glock.h" | |
24 | #include "glops.h" | |
25 | #include "inode.h" | |
26 | #include "lm.h" | |
27 | #include "lops.h" | |
28 | #include "meta_io.h" | |
29 | #include "quota.h" | |
30 | #include "super.h" | |
31 | ||
32 | /* Must be kept in sync with the beginning of struct gfs2_glock */ | |
33 | struct glock_plug { | |
34 | struct list_head gl_list; | |
35 | unsigned long gl_flags; | |
36 | }; | |
37 | ||
38 | struct greedy { | |
39 | struct gfs2_holder gr_gh; | |
40 | struct work_struct gr_work; | |
41 | }; | |
42 | ||
43 | typedef void (*glock_examiner) (struct gfs2_glock * gl); | |
44 | ||
45 | /** | |
46 | * relaxed_state_ok - is a requested lock compatible with the current lock mode? | |
47 | * @actual: the current state of the lock | |
48 | * @requested: the lock state that was requested by the caller | |
49 | * @flags: the modifier flags passed in by the caller | |
50 | * | |
51 | * Returns: 1 if the locks are compatible, 0 otherwise | |
52 | */ | |
53 | ||
54 | static inline int relaxed_state_ok(unsigned int actual, unsigned requested, | |
55 | int flags) | |
56 | { | |
57 | if (actual == requested) | |
58 | return 1; | |
59 | ||
60 | if (flags & GL_EXACT) | |
61 | return 0; | |
62 | ||
63 | if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED) | |
64 | return 1; | |
65 | ||
66 | if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY)) | |
67 | return 1; | |
68 | ||
69 | return 0; | |
70 | } | |
71 | ||
72 | /** | |
73 | * gl_hash() - Turn glock number into hash bucket number | |
74 | * @lock: The glock number | |
75 | * | |
76 | * Returns: The number of the corresponding hash bucket | |
77 | */ | |
78 | ||
79 | static unsigned int gl_hash(struct lm_lockname *name) | |
80 | { | |
81 | unsigned int h; | |
82 | ||
83 | h = jhash(&name->ln_number, sizeof(uint64_t), 0); | |
84 | h = jhash(&name->ln_type, sizeof(unsigned int), h); | |
85 | h &= GFS2_GL_HASH_MASK; | |
86 | ||
87 | return h; | |
88 | } | |
89 | ||
90 | /** | |
91 | * glock_free() - Perform a few checks and then release struct gfs2_glock | |
92 | * @gl: The glock to release | |
93 | * | |
94 | * Also calls lock module to release its internal structure for this glock. | |
95 | * | |
96 | */ | |
97 | ||
98 | static void glock_free(struct gfs2_glock *gl) | |
99 | { | |
100 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
101 | struct inode *aspace = gl->gl_aspace; | |
102 | ||
103 | gfs2_lm_put_lock(sdp, gl->gl_lock); | |
104 | ||
105 | if (aspace) | |
106 | gfs2_aspace_put(aspace); | |
107 | ||
108 | kmem_cache_free(gfs2_glock_cachep, gl); | |
b3b94faa DT |
109 | } |
110 | ||
111 | /** | |
112 | * gfs2_glock_hold() - increment reference count on glock | |
113 | * @gl: The glock to hold | |
114 | * | |
115 | */ | |
116 | ||
117 | void gfs2_glock_hold(struct gfs2_glock *gl) | |
118 | { | |
119 | kref_get(&gl->gl_ref); | |
120 | } | |
121 | ||
122 | /* All work is done after the return from kref_put() so we | |
123 | can release the write_lock before the free. */ | |
124 | ||
125 | static void kill_glock(struct kref *kref) | |
126 | { | |
127 | struct gfs2_glock *gl = container_of(kref, struct gfs2_glock, gl_ref); | |
128 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
129 | ||
130 | gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED); | |
131 | gfs2_assert(sdp, list_empty(&gl->gl_reclaim)); | |
132 | gfs2_assert(sdp, list_empty(&gl->gl_holders)); | |
133 | gfs2_assert(sdp, list_empty(&gl->gl_waiters1)); | |
134 | gfs2_assert(sdp, list_empty(&gl->gl_waiters2)); | |
135 | gfs2_assert(sdp, list_empty(&gl->gl_waiters3)); | |
136 | } | |
137 | ||
138 | /** | |
139 | * gfs2_glock_put() - Decrement reference count on glock | |
140 | * @gl: The glock to put | |
141 | * | |
142 | */ | |
143 | ||
144 | int gfs2_glock_put(struct gfs2_glock *gl) | |
145 | { | |
146 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
147 | struct gfs2_gl_hash_bucket *bucket = gl->gl_bucket; | |
148 | int rv = 0; | |
149 | ||
f55ab26a | 150 | mutex_lock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa DT |
151 | |
152 | write_lock(&bucket->hb_lock); | |
153 | if (kref_put(&gl->gl_ref, kill_glock)) { | |
154 | list_del_init(&gl->gl_list); | |
155 | write_unlock(&bucket->hb_lock); | |
156 | glock_free(gl); | |
157 | rv = 1; | |
158 | goto out; | |
159 | } | |
160 | write_unlock(&bucket->hb_lock); | |
161 | out: | |
f55ab26a | 162 | mutex_unlock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa DT |
163 | return rv; |
164 | } | |
165 | ||
166 | /** | |
167 | * queue_empty - check to see if a glock's queue is empty | |
168 | * @gl: the glock | |
169 | * @head: the head of the queue to check | |
170 | * | |
171 | * This function protects the list in the event that a process already | |
172 | * has a holder on the list and is adding a second holder for itself. | |
173 | * The glmutex lock is what generally prevents processes from working | |
174 | * on the same glock at once, but the special case of adding a second | |
175 | * holder for yourself ("recursive" locking) doesn't involve locking | |
176 | * glmutex, making the spin lock necessary. | |
177 | * | |
178 | * Returns: 1 if the queue is empty | |
179 | */ | |
180 | ||
181 | static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head) | |
182 | { | |
183 | int empty; | |
184 | spin_lock(&gl->gl_spin); | |
185 | empty = list_empty(head); | |
186 | spin_unlock(&gl->gl_spin); | |
187 | return empty; | |
188 | } | |
189 | ||
190 | /** | |
191 | * search_bucket() - Find struct gfs2_glock by lock number | |
192 | * @bucket: the bucket to search | |
193 | * @name: The lock name | |
194 | * | |
195 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
196 | */ | |
197 | ||
198 | static struct gfs2_glock *search_bucket(struct gfs2_gl_hash_bucket *bucket, | |
199 | struct lm_lockname *name) | |
200 | { | |
201 | struct gfs2_glock *gl; | |
202 | ||
203 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
204 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
205 | continue; | |
206 | if (!lm_name_equal(&gl->gl_name, name)) | |
207 | continue; | |
208 | ||
209 | kref_get(&gl->gl_ref); | |
210 | ||
211 | return gl; | |
212 | } | |
213 | ||
214 | return NULL; | |
215 | } | |
216 | ||
217 | /** | |
218 | * gfs2_glock_find() - Find glock by lock number | |
219 | * @sdp: The GFS2 superblock | |
220 | * @name: The lock name | |
221 | * | |
222 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
223 | */ | |
224 | ||
225 | struct gfs2_glock *gfs2_glock_find(struct gfs2_sbd *sdp, | |
226 | struct lm_lockname *name) | |
227 | { | |
228 | struct gfs2_gl_hash_bucket *bucket = &sdp->sd_gl_hash[gl_hash(name)]; | |
229 | struct gfs2_glock *gl; | |
230 | ||
231 | read_lock(&bucket->hb_lock); | |
232 | gl = search_bucket(bucket, name); | |
233 | read_unlock(&bucket->hb_lock); | |
234 | ||
235 | return gl; | |
236 | } | |
237 | ||
238 | /** | |
239 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
240 | * @sdp: The GFS2 superblock | |
241 | * @number: the lock number | |
242 | * @glops: The glock_operations to use | |
243 | * @create: If 0, don't create the glock if it doesn't exist | |
244 | * @glp: the glock is returned here | |
245 | * | |
246 | * This does not lock a glock, just finds/creates structures for one. | |
247 | * | |
248 | * Returns: errno | |
249 | */ | |
250 | ||
251 | int gfs2_glock_get(struct gfs2_sbd *sdp, uint64_t number, | |
252 | struct gfs2_glock_operations *glops, int create, | |
253 | struct gfs2_glock **glp) | |
254 | { | |
255 | struct lm_lockname name; | |
256 | struct gfs2_glock *gl, *tmp; | |
257 | struct gfs2_gl_hash_bucket *bucket; | |
258 | int error; | |
259 | ||
260 | name.ln_number = number; | |
261 | name.ln_type = glops->go_type; | |
262 | bucket = &sdp->sd_gl_hash[gl_hash(&name)]; | |
263 | ||
264 | read_lock(&bucket->hb_lock); | |
265 | gl = search_bucket(bucket, &name); | |
266 | read_unlock(&bucket->hb_lock); | |
267 | ||
268 | if (gl || !create) { | |
269 | *glp = gl; | |
270 | return 0; | |
271 | } | |
272 | ||
273 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); | |
274 | if (!gl) | |
275 | return -ENOMEM; | |
276 | ||
277 | memset(gl, 0, sizeof(struct gfs2_glock)); | |
278 | ||
279 | INIT_LIST_HEAD(&gl->gl_list); | |
280 | gl->gl_name = name; | |
281 | kref_init(&gl->gl_ref); | |
282 | ||
283 | spin_lock_init(&gl->gl_spin); | |
284 | ||
285 | gl->gl_state = LM_ST_UNLOCKED; | |
286 | INIT_LIST_HEAD(&gl->gl_holders); | |
287 | INIT_LIST_HEAD(&gl->gl_waiters1); | |
288 | INIT_LIST_HEAD(&gl->gl_waiters2); | |
289 | INIT_LIST_HEAD(&gl->gl_waiters3); | |
290 | ||
291 | gl->gl_ops = glops; | |
292 | ||
293 | gl->gl_bucket = bucket; | |
294 | INIT_LIST_HEAD(&gl->gl_reclaim); | |
295 | ||
296 | gl->gl_sbd = sdp; | |
297 | ||
298 | lops_init_le(&gl->gl_le, &gfs2_glock_lops); | |
299 | INIT_LIST_HEAD(&gl->gl_ail_list); | |
300 | ||
301 | /* If this glock protects actual on-disk data or metadata blocks, | |
302 | create a VFS inode to manage the pages/buffers holding them. */ | |
303 | if (glops == &gfs2_inode_glops || | |
304 | glops == &gfs2_rgrp_glops || | |
305 | glops == &gfs2_meta_glops) { | |
306 | gl->gl_aspace = gfs2_aspace_get(sdp); | |
307 | if (!gl->gl_aspace) { | |
308 | error = -ENOMEM; | |
309 | goto fail; | |
310 | } | |
311 | } | |
312 | ||
313 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
314 | if (error) | |
315 | goto fail_aspace; | |
316 | ||
b3b94faa DT |
317 | write_lock(&bucket->hb_lock); |
318 | tmp = search_bucket(bucket, &name); | |
319 | if (tmp) { | |
320 | write_unlock(&bucket->hb_lock); | |
321 | glock_free(gl); | |
322 | gl = tmp; | |
323 | } else { | |
324 | list_add_tail(&gl->gl_list, &bucket->hb_list); | |
325 | write_unlock(&bucket->hb_lock); | |
326 | } | |
327 | ||
328 | *glp = gl; | |
329 | ||
330 | return 0; | |
331 | ||
332 | fail_aspace: | |
333 | if (gl->gl_aspace) | |
334 | gfs2_aspace_put(gl->gl_aspace); | |
335 | ||
336 | fail: | |
337 | kmem_cache_free(gfs2_glock_cachep, gl); | |
338 | ||
339 | return error; | |
340 | } | |
341 | ||
342 | /** | |
343 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
344 | * @gl: the glock | |
345 | * @state: the state we're requesting | |
346 | * @flags: the modifier flags | |
347 | * @gh: the holder structure | |
348 | * | |
349 | */ | |
350 | ||
351 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, int flags, | |
352 | struct gfs2_holder *gh) | |
353 | { | |
354 | INIT_LIST_HEAD(&gh->gh_list); | |
355 | gh->gh_gl = gl; | |
356 | gh->gh_owner = (flags & GL_NEVER_RECURSE) ? NULL : current; | |
357 | gh->gh_state = state; | |
358 | gh->gh_flags = flags; | |
359 | gh->gh_error = 0; | |
360 | gh->gh_iflags = 0; | |
361 | init_completion(&gh->gh_wait); | |
362 | ||
363 | if (gh->gh_state == LM_ST_EXCLUSIVE) | |
364 | gh->gh_flags |= GL_LOCAL_EXCL; | |
365 | ||
366 | gfs2_glock_hold(gl); | |
367 | } | |
368 | ||
369 | /** | |
370 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
371 | * @state: the state we're requesting | |
372 | * @flags: the modifier flags | |
373 | * @gh: the holder structure | |
374 | * | |
375 | * Don't mess with the glock. | |
376 | * | |
377 | */ | |
378 | ||
379 | void gfs2_holder_reinit(unsigned int state, int flags, struct gfs2_holder *gh) | |
380 | { | |
381 | gh->gh_state = state; | |
382 | gh->gh_flags = flags; | |
383 | if (gh->gh_state == LM_ST_EXCLUSIVE) | |
384 | gh->gh_flags |= GL_LOCAL_EXCL; | |
385 | ||
386 | gh->gh_iflags &= 1 << HIF_ALLOCED; | |
387 | } | |
388 | ||
389 | /** | |
390 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
391 | * @gh: the holder structure | |
392 | * | |
393 | */ | |
394 | ||
395 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
396 | { | |
397 | gfs2_glock_put(gh->gh_gl); | |
398 | gh->gh_gl = NULL; | |
399 | } | |
400 | ||
401 | /** | |
402 | * gfs2_holder_get - get a struct gfs2_holder structure | |
403 | * @gl: the glock | |
404 | * @state: the state we're requesting | |
405 | * @flags: the modifier flags | |
406 | * @gfp_flags: __GFP_NOFAIL | |
407 | * | |
408 | * Figure out how big an impact this function has. Either: | |
409 | * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd | |
410 | * 2) Leave it like it is | |
411 | * | |
412 | * Returns: the holder structure, NULL on ENOMEM | |
413 | */ | |
414 | ||
415 | struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, unsigned int state, | |
416 | int flags, gfp_t gfp_flags) | |
417 | { | |
418 | struct gfs2_holder *gh; | |
419 | ||
420 | gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags); | |
421 | if (!gh) | |
422 | return NULL; | |
423 | ||
424 | gfs2_holder_init(gl, state, flags, gh); | |
425 | set_bit(HIF_ALLOCED, &gh->gh_iflags); | |
426 | ||
427 | return gh; | |
428 | } | |
429 | ||
430 | /** | |
431 | * gfs2_holder_put - get rid of a struct gfs2_holder structure | |
432 | * @gh: the holder structure | |
433 | * | |
434 | */ | |
435 | ||
436 | void gfs2_holder_put(struct gfs2_holder *gh) | |
437 | { | |
438 | gfs2_holder_uninit(gh); | |
439 | kfree(gh); | |
440 | } | |
441 | ||
442 | /** | |
443 | * handle_recurse - put other holder structures (marked recursive) | |
444 | * into the holders list | |
445 | * @gh: the holder structure | |
446 | * | |
447 | */ | |
448 | ||
449 | static void handle_recurse(struct gfs2_holder *gh) | |
450 | { | |
451 | struct gfs2_glock *gl = gh->gh_gl; | |
452 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
453 | struct gfs2_holder *tmp_gh, *safe; | |
454 | int found = 0; | |
455 | ||
456 | if (gfs2_assert_warn(sdp, gh->gh_owner)) | |
457 | return; | |
458 | ||
459 | list_for_each_entry_safe(tmp_gh, safe, &gl->gl_waiters3, gh_list) { | |
460 | if (tmp_gh->gh_owner != gh->gh_owner) | |
461 | continue; | |
462 | ||
463 | gfs2_assert_warn(sdp, | |
464 | test_bit(HIF_RECURSE, &tmp_gh->gh_iflags)); | |
465 | ||
466 | list_move_tail(&tmp_gh->gh_list, &gl->gl_holders); | |
467 | tmp_gh->gh_error = 0; | |
468 | set_bit(HIF_HOLDER, &tmp_gh->gh_iflags); | |
469 | ||
470 | complete(&tmp_gh->gh_wait); | |
471 | ||
472 | found = 1; | |
473 | } | |
474 | ||
475 | gfs2_assert_warn(sdp, found); | |
476 | } | |
477 | ||
478 | /** | |
479 | * do_unrecurse - a recursive holder was just dropped of the waiters3 list | |
480 | * @gh: the holder | |
481 | * | |
482 | * If there is only one other recursive holder, clear its HIF_RECURSE bit. | |
483 | * If there is more than one, leave them alone. | |
484 | * | |
485 | */ | |
486 | ||
487 | static void do_unrecurse(struct gfs2_holder *gh) | |
488 | { | |
489 | struct gfs2_glock *gl = gh->gh_gl; | |
490 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
491 | struct gfs2_holder *tmp_gh, *last_gh = NULL; | |
492 | int found = 0; | |
493 | ||
494 | if (gfs2_assert_warn(sdp, gh->gh_owner)) | |
495 | return; | |
496 | ||
497 | list_for_each_entry(tmp_gh, &gl->gl_waiters3, gh_list) { | |
498 | if (tmp_gh->gh_owner != gh->gh_owner) | |
499 | continue; | |
500 | ||
501 | gfs2_assert_warn(sdp, | |
502 | test_bit(HIF_RECURSE, &tmp_gh->gh_iflags)); | |
503 | ||
504 | if (found) | |
505 | return; | |
506 | ||
507 | found = 1; | |
508 | last_gh = tmp_gh; | |
509 | } | |
510 | ||
511 | if (!gfs2_assert_warn(sdp, found)) | |
512 | clear_bit(HIF_RECURSE, &last_gh->gh_iflags); | |
513 | } | |
514 | ||
515 | /** | |
516 | * rq_mutex - process a mutex request in the queue | |
517 | * @gh: the glock holder | |
518 | * | |
519 | * Returns: 1 if the queue is blocked | |
520 | */ | |
521 | ||
522 | static int rq_mutex(struct gfs2_holder *gh) | |
523 | { | |
524 | struct gfs2_glock *gl = gh->gh_gl; | |
525 | ||
526 | list_del_init(&gh->gh_list); | |
527 | /* gh->gh_error never examined. */ | |
528 | set_bit(GLF_LOCK, &gl->gl_flags); | |
529 | complete(&gh->gh_wait); | |
530 | ||
531 | return 1; | |
532 | } | |
533 | ||
534 | /** | |
535 | * rq_promote - process a promote request in the queue | |
536 | * @gh: the glock holder | |
537 | * | |
538 | * Acquire a new inter-node lock, or change a lock state to more restrictive. | |
539 | * | |
540 | * Returns: 1 if the queue is blocked | |
541 | */ | |
542 | ||
543 | static int rq_promote(struct gfs2_holder *gh) | |
544 | { | |
545 | struct gfs2_glock *gl = gh->gh_gl; | |
546 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
547 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
548 | int recurse; | |
549 | ||
550 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
551 | if (list_empty(&gl->gl_holders)) { | |
552 | gl->gl_req_gh = gh; | |
553 | set_bit(GLF_LOCK, &gl->gl_flags); | |
554 | spin_unlock(&gl->gl_spin); | |
555 | ||
556 | if (atomic_read(&sdp->sd_reclaim_count) > | |
557 | gfs2_tune_get(sdp, gt_reclaim_limit) && | |
558 | !(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
559 | gfs2_reclaim_glock(sdp); | |
560 | gfs2_reclaim_glock(sdp); | |
561 | } | |
562 | ||
563 | glops->go_xmote_th(gl, gh->gh_state, | |
564 | gh->gh_flags); | |
565 | ||
566 | spin_lock(&gl->gl_spin); | |
567 | } | |
568 | return 1; | |
569 | } | |
570 | ||
571 | if (list_empty(&gl->gl_holders)) { | |
572 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
573 | set_bit(GLF_LOCK, &gl->gl_flags); | |
574 | recurse = 0; | |
575 | } else { | |
576 | struct gfs2_holder *next_gh; | |
577 | if (gh->gh_flags & GL_LOCAL_EXCL) | |
578 | return 1; | |
579 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, | |
580 | gh_list); | |
581 | if (next_gh->gh_flags & GL_LOCAL_EXCL) | |
582 | return 1; | |
583 | recurse = test_bit(HIF_RECURSE, &gh->gh_iflags); | |
584 | } | |
585 | ||
586 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
587 | gh->gh_error = 0; | |
588 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
589 | ||
590 | if (recurse) | |
591 | handle_recurse(gh); | |
592 | ||
593 | complete(&gh->gh_wait); | |
594 | ||
595 | return 0; | |
596 | } | |
597 | ||
598 | /** | |
599 | * rq_demote - process a demote request in the queue | |
600 | * @gh: the glock holder | |
601 | * | |
602 | * Returns: 1 if the queue is blocked | |
603 | */ | |
604 | ||
605 | static int rq_demote(struct gfs2_holder *gh) | |
606 | { | |
607 | struct gfs2_glock *gl = gh->gh_gl; | |
608 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
609 | ||
610 | if (!list_empty(&gl->gl_holders)) | |
611 | return 1; | |
612 | ||
613 | if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { | |
614 | list_del_init(&gh->gh_list); | |
615 | gh->gh_error = 0; | |
616 | spin_unlock(&gl->gl_spin); | |
617 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
618 | gfs2_holder_put(gh); | |
619 | else | |
620 | complete(&gh->gh_wait); | |
621 | spin_lock(&gl->gl_spin); | |
622 | } else { | |
623 | gl->gl_req_gh = gh; | |
624 | set_bit(GLF_LOCK, &gl->gl_flags); | |
625 | spin_unlock(&gl->gl_spin); | |
626 | ||
627 | if (gh->gh_state == LM_ST_UNLOCKED || | |
628 | gl->gl_state != LM_ST_EXCLUSIVE) | |
629 | glops->go_drop_th(gl); | |
630 | else | |
631 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); | |
632 | ||
633 | spin_lock(&gl->gl_spin); | |
634 | } | |
635 | ||
636 | return 0; | |
637 | } | |
638 | ||
639 | /** | |
640 | * rq_greedy - process a queued request to drop greedy status | |
641 | * @gh: the glock holder | |
642 | * | |
643 | * Returns: 1 if the queue is blocked | |
644 | */ | |
645 | ||
646 | static int rq_greedy(struct gfs2_holder *gh) | |
647 | { | |
648 | struct gfs2_glock *gl = gh->gh_gl; | |
649 | ||
650 | list_del_init(&gh->gh_list); | |
651 | /* gh->gh_error never examined. */ | |
652 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
653 | spin_unlock(&gl->gl_spin); | |
654 | ||
655 | gfs2_holder_uninit(gh); | |
656 | kfree(container_of(gh, struct greedy, gr_gh)); | |
657 | ||
658 | spin_lock(&gl->gl_spin); | |
659 | ||
660 | return 0; | |
661 | } | |
662 | ||
663 | /** | |
664 | * run_queue - process holder structures on a glock | |
665 | * @gl: the glock | |
666 | * | |
667 | */ | |
668 | ||
669 | static void run_queue(struct gfs2_glock *gl) | |
670 | { | |
671 | struct gfs2_holder *gh; | |
672 | int blocked = 1; | |
673 | ||
674 | for (;;) { | |
675 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
676 | break; | |
677 | ||
678 | if (!list_empty(&gl->gl_waiters1)) { | |
679 | gh = list_entry(gl->gl_waiters1.next, | |
680 | struct gfs2_holder, gh_list); | |
681 | ||
682 | if (test_bit(HIF_MUTEX, &gh->gh_iflags)) | |
683 | blocked = rq_mutex(gh); | |
684 | else | |
685 | gfs2_assert_warn(gl->gl_sbd, 0); | |
686 | ||
687 | } else if (!list_empty(&gl->gl_waiters2) && | |
688 | !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { | |
689 | gh = list_entry(gl->gl_waiters2.next, | |
690 | struct gfs2_holder, gh_list); | |
691 | ||
692 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) | |
693 | blocked = rq_demote(gh); | |
694 | else if (test_bit(HIF_GREEDY, &gh->gh_iflags)) | |
695 | blocked = rq_greedy(gh); | |
696 | else | |
697 | gfs2_assert_warn(gl->gl_sbd, 0); | |
698 | ||
699 | } else if (!list_empty(&gl->gl_waiters3)) { | |
700 | gh = list_entry(gl->gl_waiters3.next, | |
701 | struct gfs2_holder, gh_list); | |
702 | ||
703 | if (test_bit(HIF_PROMOTE, &gh->gh_iflags)) | |
704 | blocked = rq_promote(gh); | |
705 | else | |
706 | gfs2_assert_warn(gl->gl_sbd, 0); | |
707 | ||
708 | } else | |
709 | break; | |
710 | ||
711 | if (blocked) | |
712 | break; | |
713 | } | |
714 | } | |
715 | ||
716 | /** | |
717 | * gfs2_glmutex_lock - acquire a local lock on a glock | |
718 | * @gl: the glock | |
719 | * | |
720 | * Gives caller exclusive access to manipulate a glock structure. | |
721 | */ | |
722 | ||
723 | void gfs2_glmutex_lock(struct gfs2_glock *gl) | |
724 | { | |
725 | struct gfs2_holder gh; | |
726 | ||
727 | gfs2_holder_init(gl, 0, 0, &gh); | |
728 | set_bit(HIF_MUTEX, &gh.gh_iflags); | |
729 | ||
730 | spin_lock(&gl->gl_spin); | |
731 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
732 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); | |
733 | else | |
734 | complete(&gh.gh_wait); | |
735 | spin_unlock(&gl->gl_spin); | |
736 | ||
737 | wait_for_completion(&gh.gh_wait); | |
738 | gfs2_holder_uninit(&gh); | |
739 | } | |
740 | ||
741 | /** | |
742 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock | |
743 | * @gl: the glock | |
744 | * | |
745 | * Returns: 1 if the glock is acquired | |
746 | */ | |
747 | ||
748 | int gfs2_glmutex_trylock(struct gfs2_glock *gl) | |
749 | { | |
750 | int acquired = 1; | |
751 | ||
752 | spin_lock(&gl->gl_spin); | |
753 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
754 | acquired = 0; | |
755 | spin_unlock(&gl->gl_spin); | |
756 | ||
757 | return acquired; | |
758 | } | |
759 | ||
760 | /** | |
761 | * gfs2_glmutex_unlock - release a local lock on a glock | |
762 | * @gl: the glock | |
763 | * | |
764 | */ | |
765 | ||
766 | void gfs2_glmutex_unlock(struct gfs2_glock *gl) | |
767 | { | |
768 | spin_lock(&gl->gl_spin); | |
769 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
770 | run_queue(gl); | |
771 | spin_unlock(&gl->gl_spin); | |
772 | } | |
773 | ||
774 | /** | |
775 | * handle_callback - add a demote request to a lock's queue | |
776 | * @gl: the glock | |
777 | * @state: the state the caller wants us to change to | |
778 | * | |
779 | */ | |
780 | ||
781 | static void handle_callback(struct gfs2_glock *gl, unsigned int state) | |
782 | { | |
783 | struct gfs2_holder *gh, *new_gh = NULL; | |
784 | ||
785 | restart: | |
786 | spin_lock(&gl->gl_spin); | |
787 | ||
788 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
789 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && | |
790 | gl->gl_req_gh != gh) { | |
791 | if (gh->gh_state != state) | |
792 | gh->gh_state = LM_ST_UNLOCKED; | |
793 | goto out; | |
794 | } | |
795 | } | |
796 | ||
797 | if (new_gh) { | |
798 | list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); | |
799 | new_gh = NULL; | |
800 | } else { | |
801 | spin_unlock(&gl->gl_spin); | |
802 | ||
803 | new_gh = gfs2_holder_get(gl, state, | |
804 | LM_FLAG_TRY | GL_NEVER_RECURSE, | |
805 | GFP_KERNEL | __GFP_NOFAIL), | |
806 | set_bit(HIF_DEMOTE, &new_gh->gh_iflags); | |
807 | set_bit(HIF_DEALLOC, &new_gh->gh_iflags); | |
808 | ||
809 | goto restart; | |
810 | } | |
811 | ||
812 | out: | |
813 | spin_unlock(&gl->gl_spin); | |
814 | ||
815 | if (new_gh) | |
816 | gfs2_holder_put(new_gh); | |
817 | } | |
818 | ||
819 | /** | |
820 | * state_change - record that the glock is now in a different state | |
821 | * @gl: the glock | |
822 | * @new_state the new state | |
823 | * | |
824 | */ | |
825 | ||
826 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
827 | { | |
b3b94faa DT |
828 | int held1, held2; |
829 | ||
830 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
831 | held2 = (new_state != LM_ST_UNLOCKED); | |
832 | ||
833 | if (held1 != held2) { | |
6a6b3d01 | 834 | if (held2) |
b3b94faa | 835 | gfs2_glock_hold(gl); |
6a6b3d01 | 836 | else |
b3b94faa | 837 | gfs2_glock_put(gl); |
b3b94faa DT |
838 | } |
839 | ||
840 | gl->gl_state = new_state; | |
841 | } | |
842 | ||
843 | /** | |
844 | * xmote_bh - Called after the lock module is done acquiring a lock | |
845 | * @gl: The glock in question | |
846 | * @ret: the int returned from the lock module | |
847 | * | |
848 | */ | |
849 | ||
850 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) | |
851 | { | |
852 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
853 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
854 | struct gfs2_holder *gh = gl->gl_req_gh; | |
855 | int prev_state = gl->gl_state; | |
856 | int op_done = 1; | |
857 | ||
858 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
859 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
860 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); | |
861 | ||
862 | state_change(gl, ret & LM_OUT_ST_MASK); | |
863 | ||
864 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { | |
865 | if (glops->go_inval) | |
866 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
867 | } else if (gl->gl_state == LM_ST_DEFERRED) { | |
868 | /* We might not want to do this here. | |
869 | Look at moving to the inode glops. */ | |
870 | if (glops->go_inval) | |
871 | glops->go_inval(gl, DIO_DATA); | |
872 | } | |
873 | ||
874 | /* Deal with each possible exit condition */ | |
875 | ||
876 | if (!gh) | |
877 | gl->gl_stamp = jiffies; | |
878 | ||
879 | else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { | |
880 | spin_lock(&gl->gl_spin); | |
881 | list_del_init(&gh->gh_list); | |
882 | gh->gh_error = -EIO; | |
883 | if (test_bit(HIF_RECURSE, &gh->gh_iflags)) | |
884 | do_unrecurse(gh); | |
885 | spin_unlock(&gl->gl_spin); | |
886 | ||
887 | } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { | |
888 | spin_lock(&gl->gl_spin); | |
889 | list_del_init(&gh->gh_list); | |
890 | if (gl->gl_state == gh->gh_state || | |
891 | gl->gl_state == LM_ST_UNLOCKED) | |
892 | gh->gh_error = 0; | |
893 | else { | |
894 | if (gfs2_assert_warn(sdp, gh->gh_flags & | |
895 | (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) | |
896 | fs_warn(sdp, "ret = 0x%.8X\n", ret); | |
897 | gh->gh_error = GLR_TRYFAILED; | |
898 | } | |
899 | spin_unlock(&gl->gl_spin); | |
900 | ||
901 | if (ret & LM_OUT_CANCELED) | |
902 | handle_callback(gl, LM_ST_UNLOCKED); /* Lame */ | |
903 | ||
904 | } else if (ret & LM_OUT_CANCELED) { | |
905 | spin_lock(&gl->gl_spin); | |
906 | list_del_init(&gh->gh_list); | |
907 | gh->gh_error = GLR_CANCELED; | |
908 | if (test_bit(HIF_RECURSE, &gh->gh_iflags)) | |
909 | do_unrecurse(gh); | |
910 | spin_unlock(&gl->gl_spin); | |
911 | ||
912 | } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
913 | spin_lock(&gl->gl_spin); | |
914 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
915 | gh->gh_error = 0; | |
916 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
917 | spin_unlock(&gl->gl_spin); | |
918 | ||
919 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
920 | ||
921 | op_done = 0; | |
922 | ||
923 | } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
924 | spin_lock(&gl->gl_spin); | |
925 | list_del_init(&gh->gh_list); | |
926 | gh->gh_error = GLR_TRYFAILED; | |
927 | if (test_bit(HIF_RECURSE, &gh->gh_iflags)) | |
928 | do_unrecurse(gh); | |
929 | spin_unlock(&gl->gl_spin); | |
930 | ||
931 | } else { | |
932 | if (gfs2_assert_withdraw(sdp, 0) == -1) | |
933 | fs_err(sdp, "ret = 0x%.8X\n", ret); | |
934 | } | |
935 | ||
936 | if (glops->go_xmote_bh) | |
937 | glops->go_xmote_bh(gl); | |
938 | ||
939 | if (op_done) { | |
940 | spin_lock(&gl->gl_spin); | |
941 | gl->gl_req_gh = NULL; | |
942 | gl->gl_req_bh = NULL; | |
943 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
944 | run_queue(gl); | |
945 | spin_unlock(&gl->gl_spin); | |
946 | } | |
947 | ||
948 | gfs2_glock_put(gl); | |
949 | ||
950 | if (gh) { | |
951 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
952 | gfs2_holder_put(gh); | |
953 | else | |
954 | complete(&gh->gh_wait); | |
955 | } | |
956 | } | |
957 | ||
958 | /** | |
959 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock | |
960 | * @gl: The glock in question | |
961 | * @state: the requested state | |
962 | * @flags: modifier flags to the lock call | |
963 | * | |
964 | */ | |
965 | ||
966 | void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags) | |
967 | { | |
968 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
969 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
970 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | | |
971 | LM_FLAG_NOEXP | LM_FLAG_ANY | | |
972 | LM_FLAG_PRIORITY); | |
973 | unsigned int lck_ret; | |
974 | ||
975 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
976 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
977 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); | |
978 | gfs2_assert_warn(sdp, state != gl->gl_state); | |
979 | ||
980 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
981 | if (glops->go_sync) | |
982 | glops->go_sync(gl, | |
983 | DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
984 | } | |
985 | ||
986 | gfs2_glock_hold(gl); | |
987 | gl->gl_req_bh = xmote_bh; | |
988 | ||
b3b94faa DT |
989 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, |
990 | lck_flags); | |
991 | ||
992 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) | |
993 | return; | |
994 | ||
995 | if (lck_ret & LM_OUT_ASYNC) | |
996 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); | |
997 | else | |
998 | xmote_bh(gl, lck_ret); | |
999 | } | |
1000 | ||
1001 | /** | |
1002 | * drop_bh - Called after a lock module unlock completes | |
1003 | * @gl: the glock | |
1004 | * @ret: the return status | |
1005 | * | |
1006 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) | |
1007 | * Doesn't drop the reference on the glock the top half took out | |
1008 | * | |
1009 | */ | |
1010 | ||
1011 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) | |
1012 | { | |
1013 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1014 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1015 | struct gfs2_holder *gh = gl->gl_req_gh; | |
1016 | ||
1017 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
1018 | ||
1019 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1020 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
1021 | gfs2_assert_warn(sdp, !ret); | |
1022 | ||
1023 | state_change(gl, LM_ST_UNLOCKED); | |
1024 | ||
1025 | if (glops->go_inval) | |
1026 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
1027 | ||
1028 | if (gh) { | |
1029 | spin_lock(&gl->gl_spin); | |
1030 | list_del_init(&gh->gh_list); | |
1031 | gh->gh_error = 0; | |
1032 | spin_unlock(&gl->gl_spin); | |
1033 | } | |
1034 | ||
1035 | if (glops->go_drop_bh) | |
1036 | glops->go_drop_bh(gl); | |
1037 | ||
1038 | spin_lock(&gl->gl_spin); | |
1039 | gl->gl_req_gh = NULL; | |
1040 | gl->gl_req_bh = NULL; | |
1041 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1042 | run_queue(gl); | |
1043 | spin_unlock(&gl->gl_spin); | |
1044 | ||
1045 | gfs2_glock_put(gl); | |
1046 | ||
1047 | if (gh) { | |
1048 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
1049 | gfs2_holder_put(gh); | |
1050 | else | |
1051 | complete(&gh->gh_wait); | |
1052 | } | |
1053 | } | |
1054 | ||
1055 | /** | |
1056 | * gfs2_glock_drop_th - call into the lock module to unlock a lock | |
1057 | * @gl: the glock | |
1058 | * | |
1059 | */ | |
1060 | ||
1061 | void gfs2_glock_drop_th(struct gfs2_glock *gl) | |
1062 | { | |
1063 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1064 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1065 | unsigned int ret; | |
1066 | ||
1067 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1068 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
1069 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); | |
1070 | ||
1071 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
1072 | if (glops->go_sync) | |
1073 | glops->go_sync(gl, | |
1074 | DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
1075 | } | |
1076 | ||
1077 | gfs2_glock_hold(gl); | |
1078 | gl->gl_req_bh = drop_bh; | |
1079 | ||
b3b94faa DT |
1080 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
1081 | ||
1082 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) | |
1083 | return; | |
1084 | ||
1085 | if (!ret) | |
1086 | drop_bh(gl, ret); | |
1087 | else | |
1088 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); | |
1089 | } | |
1090 | ||
1091 | /** | |
1092 | * do_cancels - cancel requests for locks stuck waiting on an expire flag | |
1093 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock | |
1094 | * | |
1095 | * Don't cancel GL_NOCANCEL requests. | |
1096 | */ | |
1097 | ||
1098 | static void do_cancels(struct gfs2_holder *gh) | |
1099 | { | |
1100 | struct gfs2_glock *gl = gh->gh_gl; | |
1101 | ||
1102 | spin_lock(&gl->gl_spin); | |
1103 | ||
1104 | while (gl->gl_req_gh != gh && | |
1105 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1106 | !list_empty(&gh->gh_list)) { | |
1107 | if (gl->gl_req_bh && | |
1108 | !(gl->gl_req_gh && | |
1109 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { | |
1110 | spin_unlock(&gl->gl_spin); | |
1111 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); | |
1112 | msleep(100); | |
1113 | spin_lock(&gl->gl_spin); | |
1114 | } else { | |
1115 | spin_unlock(&gl->gl_spin); | |
1116 | msleep(100); | |
1117 | spin_lock(&gl->gl_spin); | |
1118 | } | |
1119 | } | |
1120 | ||
1121 | spin_unlock(&gl->gl_spin); | |
1122 | } | |
1123 | ||
1124 | /** | |
1125 | * glock_wait_internal - wait on a glock acquisition | |
1126 | * @gh: the glock holder | |
1127 | * | |
1128 | * Returns: 0 on success | |
1129 | */ | |
1130 | ||
1131 | static int glock_wait_internal(struct gfs2_holder *gh) | |
1132 | { | |
1133 | struct gfs2_glock *gl = gh->gh_gl; | |
1134 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1135 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1136 | ||
1137 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) | |
1138 | return -EIO; | |
1139 | ||
1140 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
1141 | spin_lock(&gl->gl_spin); | |
1142 | if (gl->gl_req_gh != gh && | |
1143 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1144 | !list_empty(&gh->gh_list)) { | |
1145 | list_del_init(&gh->gh_list); | |
1146 | gh->gh_error = GLR_TRYFAILED; | |
1147 | if (test_bit(HIF_RECURSE, &gh->gh_iflags)) | |
1148 | do_unrecurse(gh); | |
1149 | run_queue(gl); | |
1150 | spin_unlock(&gl->gl_spin); | |
1151 | return gh->gh_error; | |
1152 | } | |
1153 | spin_unlock(&gl->gl_spin); | |
1154 | } | |
1155 | ||
1156 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1157 | do_cancels(gh); | |
1158 | ||
1159 | wait_for_completion(&gh->gh_wait); | |
1160 | ||
1161 | if (gh->gh_error) | |
1162 | return gh->gh_error; | |
1163 | ||
1164 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); | |
1165 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, | |
1166 | gh->gh_state, | |
1167 | gh->gh_flags)); | |
1168 | ||
1169 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { | |
1170 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1171 | ||
1172 | if (glops->go_lock) { | |
1173 | gh->gh_error = glops->go_lock(gh); | |
1174 | if (gh->gh_error) { | |
1175 | spin_lock(&gl->gl_spin); | |
1176 | list_del_init(&gh->gh_list); | |
1177 | if (test_and_clear_bit(HIF_RECURSE, | |
1178 | &gh->gh_iflags)) | |
1179 | do_unrecurse(gh); | |
1180 | spin_unlock(&gl->gl_spin); | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | spin_lock(&gl->gl_spin); | |
1185 | gl->gl_req_gh = NULL; | |
1186 | gl->gl_req_bh = NULL; | |
1187 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1188 | if (test_bit(HIF_RECURSE, &gh->gh_iflags)) | |
1189 | handle_recurse(gh); | |
1190 | run_queue(gl); | |
1191 | spin_unlock(&gl->gl_spin); | |
1192 | } | |
1193 | ||
1194 | return gh->gh_error; | |
1195 | } | |
1196 | ||
1197 | static inline struct gfs2_holder * | |
1198 | find_holder_by_owner(struct list_head *head, struct task_struct *owner) | |
1199 | { | |
1200 | struct gfs2_holder *gh; | |
1201 | ||
1202 | list_for_each_entry(gh, head, gh_list) { | |
1203 | if (gh->gh_owner == owner) | |
1204 | return gh; | |
1205 | } | |
1206 | ||
1207 | return NULL; | |
1208 | } | |
1209 | ||
1210 | /** | |
1211 | * recurse_check - | |
1212 | * | |
1213 | * Make sure the new holder is compatible with the pre-existing one. | |
1214 | * | |
1215 | */ | |
1216 | ||
1217 | static int recurse_check(struct gfs2_holder *existing, struct gfs2_holder *new, | |
1218 | unsigned int state) | |
1219 | { | |
1220 | struct gfs2_sbd *sdp = existing->gh_gl->gl_sbd; | |
1221 | ||
1222 | if (gfs2_assert_warn(sdp, (new->gh_flags & LM_FLAG_ANY) || | |
1223 | !(existing->gh_flags & LM_FLAG_ANY))) | |
1224 | goto fail; | |
1225 | ||
1226 | if (gfs2_assert_warn(sdp, (existing->gh_flags & GL_LOCAL_EXCL) || | |
1227 | !(new->gh_flags & GL_LOCAL_EXCL))) | |
1228 | goto fail; | |
1229 | ||
1230 | if (gfs2_assert_warn(sdp, relaxed_state_ok(state, new->gh_state, | |
1231 | new->gh_flags))) | |
1232 | goto fail; | |
1233 | ||
1234 | return 0; | |
1235 | ||
1236 | fail: | |
1237 | set_bit(HIF_ABORTED, &new->gh_iflags); | |
1238 | return -EINVAL; | |
1239 | } | |
1240 | ||
1241 | /** | |
1242 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
1243 | * @gh: the holder structure to add | |
1244 | * | |
1245 | */ | |
1246 | ||
1247 | static void add_to_queue(struct gfs2_holder *gh) | |
1248 | { | |
1249 | struct gfs2_glock *gl = gh->gh_gl; | |
1250 | struct gfs2_holder *existing; | |
1251 | ||
1252 | if (!gh->gh_owner) | |
1253 | goto out; | |
1254 | ||
1255 | existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner); | |
1256 | if (existing) { | |
1257 | if (recurse_check(existing, gh, gl->gl_state)) | |
1258 | return; | |
1259 | ||
1260 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
1261 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
1262 | ||
1263 | gh->gh_error = 0; | |
1264 | complete(&gh->gh_wait); | |
1265 | ||
1266 | return; | |
1267 | } | |
1268 | ||
1269 | existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner); | |
1270 | if (existing) { | |
1271 | if (recurse_check(existing, gh, existing->gh_state)) | |
1272 | return; | |
1273 | ||
1274 | set_bit(HIF_RECURSE, &gh->gh_iflags); | |
1275 | set_bit(HIF_RECURSE, &existing->gh_iflags); | |
1276 | ||
1277 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); | |
1278 | ||
1279 | return; | |
1280 | } | |
1281 | ||
1282 | out: | |
1283 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1284 | list_add(&gh->gh_list, &gl->gl_waiters3); | |
1285 | else | |
1286 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); | |
1287 | } | |
1288 | ||
1289 | /** | |
1290 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1291 | * @gh: the holder structure | |
1292 | * | |
1293 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1294 | * | |
1295 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1296 | */ | |
1297 | ||
1298 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1299 | { | |
1300 | struct gfs2_glock *gl = gh->gh_gl; | |
1301 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1302 | int error = 0; | |
1303 | ||
b3b94faa DT |
1304 | restart: |
1305 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { | |
1306 | set_bit(HIF_ABORTED, &gh->gh_iflags); | |
1307 | return -EIO; | |
1308 | } | |
1309 | ||
1310 | set_bit(HIF_PROMOTE, &gh->gh_iflags); | |
1311 | ||
1312 | spin_lock(&gl->gl_spin); | |
1313 | add_to_queue(gh); | |
1314 | run_queue(gl); | |
1315 | spin_unlock(&gl->gl_spin); | |
1316 | ||
1317 | if (!(gh->gh_flags & GL_ASYNC)) { | |
1318 | error = glock_wait_internal(gh); | |
1319 | if (error == GLR_CANCELED) { | |
1320 | msleep(1000); | |
1321 | goto restart; | |
1322 | } | |
1323 | } | |
1324 | ||
1325 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
1326 | ||
1327 | return error; | |
1328 | } | |
1329 | ||
1330 | /** | |
1331 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1332 | * @gh: the holder | |
1333 | * | |
1334 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1335 | */ | |
1336 | ||
1337 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1338 | { | |
1339 | struct gfs2_glock *gl = gh->gh_gl; | |
1340 | int ready = 0; | |
1341 | ||
1342 | spin_lock(&gl->gl_spin); | |
1343 | ||
1344 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1345 | ready = 1; | |
1346 | else if (list_empty(&gh->gh_list)) { | |
1347 | if (gh->gh_error == GLR_CANCELED) { | |
1348 | spin_unlock(&gl->gl_spin); | |
1349 | msleep(1000); | |
1350 | if (gfs2_glock_nq(gh)) | |
1351 | return 1; | |
1352 | return 0; | |
1353 | } else | |
1354 | ready = 1; | |
1355 | } | |
1356 | ||
1357 | spin_unlock(&gl->gl_spin); | |
1358 | ||
1359 | return ready; | |
1360 | } | |
1361 | ||
1362 | /** | |
1363 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC | |
1364 | * @gh: the holder structure | |
1365 | * | |
1366 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1367 | */ | |
1368 | ||
1369 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
1370 | { | |
1371 | int error; | |
1372 | ||
1373 | error = glock_wait_internal(gh); | |
1374 | if (error == GLR_CANCELED) { | |
1375 | msleep(1000); | |
1376 | gh->gh_flags &= ~GL_ASYNC; | |
1377 | error = gfs2_glock_nq(gh); | |
1378 | } | |
1379 | ||
1380 | return error; | |
1381 | } | |
1382 | ||
1383 | /** | |
1384 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1385 | * @gh: the glock holder | |
1386 | * | |
1387 | */ | |
1388 | ||
1389 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1390 | { | |
1391 | struct gfs2_glock *gl = gh->gh_gl; | |
b3b94faa DT |
1392 | struct gfs2_glock_operations *glops = gl->gl_ops; |
1393 | ||
b3b94faa DT |
1394 | if (gh->gh_flags & GL_SYNC) |
1395 | set_bit(GLF_SYNC, &gl->gl_flags); | |
1396 | ||
1397 | if (gh->gh_flags & GL_NOCACHE) | |
1398 | handle_callback(gl, LM_ST_UNLOCKED); | |
1399 | ||
1400 | gfs2_glmutex_lock(gl); | |
1401 | ||
1402 | spin_lock(&gl->gl_spin); | |
1403 | list_del_init(&gh->gh_list); | |
1404 | ||
1405 | if (list_empty(&gl->gl_holders)) { | |
1406 | spin_unlock(&gl->gl_spin); | |
1407 | ||
1408 | if (glops->go_unlock) | |
1409 | glops->go_unlock(gh); | |
1410 | ||
1411 | if (test_bit(GLF_SYNC, &gl->gl_flags)) { | |
1412 | if (glops->go_sync) | |
1413 | glops->go_sync(gl, DIO_METADATA | DIO_DATA); | |
1414 | } | |
1415 | ||
1416 | gl->gl_stamp = jiffies; | |
1417 | ||
1418 | spin_lock(&gl->gl_spin); | |
1419 | } | |
1420 | ||
1421 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1422 | run_queue(gl); | |
1423 | spin_unlock(&gl->gl_spin); | |
1424 | } | |
1425 | ||
1426 | /** | |
1427 | * gfs2_glock_prefetch - Try to prefetch a glock | |
1428 | * @gl: the glock | |
1429 | * @state: the state to prefetch in | |
1430 | * @flags: flags passed to go_xmote_th() | |
1431 | * | |
1432 | */ | |
1433 | ||
1434 | void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state, int flags) | |
1435 | { | |
1436 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1437 | ||
1438 | spin_lock(&gl->gl_spin); | |
1439 | ||
1440 | if (test_bit(GLF_LOCK, &gl->gl_flags) || | |
1441 | !list_empty(&gl->gl_holders) || | |
1442 | !list_empty(&gl->gl_waiters1) || | |
1443 | !list_empty(&gl->gl_waiters2) || | |
1444 | !list_empty(&gl->gl_waiters3) || | |
1445 | relaxed_state_ok(gl->gl_state, state, flags)) { | |
1446 | spin_unlock(&gl->gl_spin); | |
1447 | return; | |
1448 | } | |
1449 | ||
1450 | set_bit(GLF_PREFETCH, &gl->gl_flags); | |
1451 | set_bit(GLF_LOCK, &gl->gl_flags); | |
1452 | spin_unlock(&gl->gl_spin); | |
1453 | ||
1454 | glops->go_xmote_th(gl, state, flags); | |
b3b94faa DT |
1455 | } |
1456 | ||
1457 | /** | |
1458 | * gfs2_glock_force_drop - Force a glock to be uncached | |
1459 | * @gl: the glock | |
1460 | * | |
1461 | */ | |
1462 | ||
1463 | void gfs2_glock_force_drop(struct gfs2_glock *gl) | |
1464 | { | |
1465 | struct gfs2_holder gh; | |
1466 | ||
1467 | gfs2_holder_init(gl, LM_ST_UNLOCKED, GL_NEVER_RECURSE, &gh); | |
1468 | set_bit(HIF_DEMOTE, &gh.gh_iflags); | |
1469 | ||
1470 | spin_lock(&gl->gl_spin); | |
1471 | list_add_tail(&gh.gh_list, &gl->gl_waiters2); | |
1472 | run_queue(gl); | |
1473 | spin_unlock(&gl->gl_spin); | |
1474 | ||
1475 | wait_for_completion(&gh.gh_wait); | |
1476 | gfs2_holder_uninit(&gh); | |
1477 | } | |
1478 | ||
1479 | static void greedy_work(void *data) | |
1480 | { | |
1481 | struct greedy *gr = (struct greedy *)data; | |
1482 | struct gfs2_holder *gh = &gr->gr_gh; | |
1483 | struct gfs2_glock *gl = gh->gh_gl; | |
1484 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1485 | ||
1486 | clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1487 | ||
1488 | if (glops->go_greedy) | |
1489 | glops->go_greedy(gl); | |
1490 | ||
1491 | spin_lock(&gl->gl_spin); | |
1492 | ||
1493 | if (list_empty(&gl->gl_waiters2)) { | |
1494 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1495 | spin_unlock(&gl->gl_spin); | |
1496 | gfs2_holder_uninit(gh); | |
1497 | kfree(gr); | |
1498 | } else { | |
1499 | gfs2_glock_hold(gl); | |
1500 | list_add_tail(&gh->gh_list, &gl->gl_waiters2); | |
1501 | run_queue(gl); | |
1502 | spin_unlock(&gl->gl_spin); | |
1503 | gfs2_glock_put(gl); | |
1504 | } | |
1505 | } | |
1506 | ||
1507 | /** | |
1508 | * gfs2_glock_be_greedy - | |
1509 | * @gl: | |
1510 | * @time: | |
1511 | * | |
1512 | * Returns: 0 if go_greedy will be called, 1 otherwise | |
1513 | */ | |
1514 | ||
1515 | int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time) | |
1516 | { | |
1517 | struct greedy *gr; | |
1518 | struct gfs2_holder *gh; | |
1519 | ||
1520 | if (!time || | |
1521 | gl->gl_sbd->sd_args.ar_localcaching || | |
1522 | test_and_set_bit(GLF_GREEDY, &gl->gl_flags)) | |
1523 | return 1; | |
1524 | ||
1525 | gr = kmalloc(sizeof(struct greedy), GFP_KERNEL); | |
1526 | if (!gr) { | |
1527 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1528 | return 1; | |
1529 | } | |
1530 | gh = &gr->gr_gh; | |
1531 | ||
1532 | gfs2_holder_init(gl, 0, GL_NEVER_RECURSE, gh); | |
1533 | set_bit(HIF_GREEDY, &gh->gh_iflags); | |
1534 | INIT_WORK(&gr->gr_work, greedy_work, gr); | |
1535 | ||
1536 | set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1537 | schedule_delayed_work(&gr->gr_work, time); | |
1538 | ||
1539 | return 0; | |
1540 | } | |
1541 | ||
1542 | /** | |
1543 | * gfs2_glock_nq_init - intialize a holder and enqueue it on a glock | |
1544 | * @gl: the glock | |
1545 | * @state: the state we're requesting | |
1546 | * @flags: the modifier flags | |
1547 | * @gh: the holder structure | |
1548 | * | |
1549 | * Returns: 0, GLR_*, or errno | |
1550 | */ | |
1551 | ||
1552 | int gfs2_glock_nq_init(struct gfs2_glock *gl, unsigned int state, int flags, | |
1553 | struct gfs2_holder *gh) | |
1554 | { | |
1555 | int error; | |
1556 | ||
1557 | gfs2_holder_init(gl, state, flags, gh); | |
1558 | ||
1559 | error = gfs2_glock_nq(gh); | |
1560 | if (error) | |
1561 | gfs2_holder_uninit(gh); | |
1562 | ||
1563 | return error; | |
1564 | } | |
1565 | ||
1566 | /** | |
1567 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1568 | * @gh: the holder structure | |
1569 | * | |
1570 | */ | |
1571 | ||
1572 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1573 | { | |
1574 | gfs2_glock_dq(gh); | |
1575 | gfs2_holder_uninit(gh); | |
1576 | } | |
1577 | ||
1578 | /** | |
1579 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1580 | * @sdp: the filesystem | |
1581 | * @number: the lock number | |
1582 | * @glops: the glock operations for the type of glock | |
1583 | * @state: the state to acquire the glock in | |
1584 | * @flags: modifier flags for the aquisition | |
1585 | * @gh: the struct gfs2_holder | |
1586 | * | |
1587 | * Returns: errno | |
1588 | */ | |
1589 | ||
1590 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, uint64_t number, | |
1591 | struct gfs2_glock_operations *glops, unsigned int state, | |
1592 | int flags, struct gfs2_holder *gh) | |
1593 | { | |
1594 | struct gfs2_glock *gl; | |
1595 | int error; | |
1596 | ||
1597 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1598 | if (!error) { | |
1599 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1600 | gfs2_glock_put(gl); | |
1601 | } | |
1602 | ||
1603 | return error; | |
1604 | } | |
1605 | ||
1606 | /** | |
1607 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1608 | * @arg_a: the first structure | |
1609 | * @arg_b: the second structure | |
1610 | * | |
1611 | */ | |
1612 | ||
1613 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1614 | { | |
1615 | struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a; | |
1616 | struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b; | |
1617 | struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1618 | struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
1619 | int ret = 0; | |
1620 | ||
1621 | if (a->ln_number > b->ln_number) | |
1622 | ret = 1; | |
1623 | else if (a->ln_number < b->ln_number) | |
1624 | ret = -1; | |
1625 | else { | |
1626 | if (gh_a->gh_state == LM_ST_SHARED && | |
1627 | gh_b->gh_state == LM_ST_EXCLUSIVE) | |
1628 | ret = 1; | |
1629 | else if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && | |
1630 | (gh_b->gh_flags & GL_LOCAL_EXCL)) | |
1631 | ret = 1; | |
1632 | } | |
1633 | ||
1634 | return ret; | |
1635 | } | |
1636 | ||
1637 | /** | |
1638 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1639 | * @num_gh: the number of structures | |
1640 | * @ghs: an array of struct gfs2_holder structures | |
1641 | * | |
1642 | * Returns: 0 on success (all glocks acquired), | |
1643 | * errno on failure (no glocks acquired) | |
1644 | */ | |
1645 | ||
1646 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1647 | struct gfs2_holder **p) | |
1648 | { | |
1649 | unsigned int x; | |
1650 | int error = 0; | |
1651 | ||
1652 | for (x = 0; x < num_gh; x++) | |
1653 | p[x] = &ghs[x]; | |
1654 | ||
1655 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1656 | ||
1657 | for (x = 0; x < num_gh; x++) { | |
1658 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1659 | ||
1660 | error = gfs2_glock_nq(p[x]); | |
1661 | if (error) { | |
1662 | while (x--) | |
1663 | gfs2_glock_dq(p[x]); | |
1664 | break; | |
1665 | } | |
1666 | } | |
1667 | ||
1668 | return error; | |
1669 | } | |
1670 | ||
1671 | /** | |
1672 | * gfs2_glock_nq_m - acquire multiple glocks | |
1673 | * @num_gh: the number of structures | |
1674 | * @ghs: an array of struct gfs2_holder structures | |
1675 | * | |
1676 | * Figure out how big an impact this function has. Either: | |
1677 | * 1) Replace this code with code that calls gfs2_glock_prefetch() | |
1678 | * 2) Forget async stuff and just call nq_m_sync() | |
1679 | * 3) Leave it like it is | |
1680 | * | |
1681 | * Returns: 0 on success (all glocks acquired), | |
1682 | * errno on failure (no glocks acquired) | |
1683 | */ | |
1684 | ||
1685 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1686 | { | |
1687 | int *e; | |
1688 | unsigned int x; | |
1689 | int borked = 0, serious = 0; | |
1690 | int error = 0; | |
1691 | ||
1692 | if (!num_gh) | |
1693 | return 0; | |
1694 | ||
1695 | if (num_gh == 1) { | |
1696 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1697 | return gfs2_glock_nq(ghs); | |
1698 | } | |
1699 | ||
1700 | e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL); | |
1701 | if (!e) | |
1702 | return -ENOMEM; | |
1703 | ||
1704 | for (x = 0; x < num_gh; x++) { | |
1705 | ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC; | |
1706 | error = gfs2_glock_nq(&ghs[x]); | |
1707 | if (error) { | |
1708 | borked = 1; | |
1709 | serious = error; | |
1710 | num_gh = x; | |
1711 | break; | |
1712 | } | |
1713 | } | |
1714 | ||
1715 | for (x = 0; x < num_gh; x++) { | |
1716 | error = e[x] = glock_wait_internal(&ghs[x]); | |
1717 | if (error) { | |
1718 | borked = 1; | |
1719 | if (error != GLR_TRYFAILED && error != GLR_CANCELED) | |
1720 | serious = error; | |
1721 | } | |
1722 | } | |
1723 | ||
1724 | if (!borked) { | |
1725 | kfree(e); | |
1726 | return 0; | |
1727 | } | |
1728 | ||
1729 | for (x = 0; x < num_gh; x++) | |
1730 | if (!e[x]) | |
1731 | gfs2_glock_dq(&ghs[x]); | |
1732 | ||
1733 | if (serious) | |
1734 | error = serious; | |
1735 | else { | |
1736 | for (x = 0; x < num_gh; x++) | |
1737 | gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags, | |
1738 | &ghs[x]); | |
1739 | error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e); | |
1740 | } | |
1741 | ||
1742 | kfree(e); | |
1743 | ||
1744 | return error; | |
1745 | } | |
1746 | ||
1747 | /** | |
1748 | * gfs2_glock_dq_m - release multiple glocks | |
1749 | * @num_gh: the number of structures | |
1750 | * @ghs: an array of struct gfs2_holder structures | |
1751 | * | |
1752 | */ | |
1753 | ||
1754 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1755 | { | |
1756 | unsigned int x; | |
1757 | ||
1758 | for (x = 0; x < num_gh; x++) | |
1759 | gfs2_glock_dq(&ghs[x]); | |
1760 | } | |
1761 | ||
1762 | /** | |
1763 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1764 | * @num_gh: the number of structures | |
1765 | * @ghs: an array of struct gfs2_holder structures | |
1766 | * | |
1767 | */ | |
1768 | ||
1769 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1770 | { | |
1771 | unsigned int x; | |
1772 | ||
1773 | for (x = 0; x < num_gh; x++) | |
1774 | gfs2_glock_dq_uninit(&ghs[x]); | |
1775 | } | |
1776 | ||
1777 | /** | |
1778 | * gfs2_glock_prefetch_num - prefetch a glock based on lock number | |
1779 | * @sdp: the filesystem | |
1780 | * @number: the lock number | |
1781 | * @glops: the glock operations for the type of glock | |
1782 | * @state: the state to acquire the glock in | |
1783 | * @flags: modifier flags for the aquisition | |
1784 | * | |
1785 | * Returns: errno | |
1786 | */ | |
1787 | ||
1788 | void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, uint64_t number, | |
1789 | struct gfs2_glock_operations *glops, | |
1790 | unsigned int state, int flags) | |
1791 | { | |
1792 | struct gfs2_glock *gl; | |
1793 | int error; | |
1794 | ||
1795 | if (atomic_read(&sdp->sd_reclaim_count) < | |
1796 | gfs2_tune_get(sdp, gt_reclaim_limit)) { | |
1797 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1798 | if (!error) { | |
1799 | gfs2_glock_prefetch(gl, state, flags); | |
1800 | gfs2_glock_put(gl); | |
1801 | } | |
1802 | } | |
1803 | } | |
1804 | ||
1805 | /** | |
1806 | * gfs2_lvb_hold - attach a LVB from a glock | |
1807 | * @gl: The glock in question | |
1808 | * | |
1809 | */ | |
1810 | ||
1811 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1812 | { | |
1813 | int error; | |
1814 | ||
1815 | gfs2_glmutex_lock(gl); | |
1816 | ||
1817 | if (!atomic_read(&gl->gl_lvb_count)) { | |
1818 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
1819 | if (error) { | |
1820 | gfs2_glmutex_unlock(gl); | |
1821 | return error; | |
1822 | } | |
1823 | gfs2_glock_hold(gl); | |
1824 | } | |
1825 | atomic_inc(&gl->gl_lvb_count); | |
1826 | ||
1827 | gfs2_glmutex_unlock(gl); | |
1828 | ||
1829 | return 0; | |
1830 | } | |
1831 | ||
1832 | /** | |
1833 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1834 | * @gl: The glock in question | |
1835 | * | |
1836 | */ | |
1837 | ||
1838 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1839 | { | |
1840 | gfs2_glock_hold(gl); | |
1841 | gfs2_glmutex_lock(gl); | |
1842 | ||
1843 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); | |
1844 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
1845 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1846 | gl->gl_lvb = NULL; | |
1847 | gfs2_glock_put(gl); | |
1848 | } | |
1849 | ||
1850 | gfs2_glmutex_unlock(gl); | |
1851 | gfs2_glock_put(gl); | |
1852 | } | |
1853 | ||
1854 | void gfs2_lvb_sync(struct gfs2_glock *gl) | |
1855 | { | |
1856 | gfs2_glmutex_lock(gl); | |
1857 | ||
1858 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count)); | |
1859 | if (!gfs2_assert_warn(gl->gl_sbd, gfs2_glock_is_held_excl(gl))) | |
1860 | gfs2_lm_sync_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1861 | ||
1862 | gfs2_glmutex_unlock(gl); | |
1863 | } | |
1864 | ||
1865 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, | |
1866 | unsigned int state) | |
1867 | { | |
1868 | struct gfs2_glock *gl; | |
1869 | ||
1870 | gl = gfs2_glock_find(sdp, name); | |
1871 | if (!gl) | |
1872 | return; | |
1873 | ||
1874 | if (gl->gl_ops->go_callback) | |
1875 | gl->gl_ops->go_callback(gl, state); | |
1876 | handle_callback(gl, state); | |
1877 | ||
1878 | spin_lock(&gl->gl_spin); | |
1879 | run_queue(gl); | |
1880 | spin_unlock(&gl->gl_spin); | |
1881 | ||
1882 | gfs2_glock_put(gl); | |
1883 | } | |
1884 | ||
1885 | /** | |
1886 | * gfs2_glock_cb - Callback used by locking module | |
1887 | * @fsdata: Pointer to the superblock | |
1888 | * @type: Type of callback | |
1889 | * @data: Type dependent data pointer | |
1890 | * | |
1891 | * Called by the locking module when it wants to tell us something. | |
1892 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1893 | * a journal from another client needs to be recovered. | |
1894 | */ | |
1895 | ||
1896 | void gfs2_glock_cb(lm_fsdata_t *fsdata, unsigned int type, void *data) | |
1897 | { | |
1898 | struct gfs2_sbd *sdp = (struct gfs2_sbd *)fsdata; | |
1899 | ||
b3b94faa DT |
1900 | switch (type) { |
1901 | case LM_CB_NEED_E: | |
1902 | blocking_cb(sdp, (struct lm_lockname *)data, LM_ST_UNLOCKED); | |
1903 | return; | |
1904 | ||
1905 | case LM_CB_NEED_D: | |
1906 | blocking_cb(sdp, (struct lm_lockname *)data, LM_ST_DEFERRED); | |
1907 | return; | |
1908 | ||
1909 | case LM_CB_NEED_S: | |
1910 | blocking_cb(sdp, (struct lm_lockname *)data, LM_ST_SHARED); | |
1911 | return; | |
1912 | ||
1913 | case LM_CB_ASYNC: { | |
1914 | struct lm_async_cb *async = (struct lm_async_cb *)data; | |
1915 | struct gfs2_glock *gl; | |
1916 | ||
1917 | gl = gfs2_glock_find(sdp, &async->lc_name); | |
1918 | if (gfs2_assert_warn(sdp, gl)) | |
1919 | return; | |
1920 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) | |
1921 | gl->gl_req_bh(gl, async->lc_ret); | |
1922 | gfs2_glock_put(gl); | |
1923 | ||
1924 | return; | |
1925 | } | |
1926 | ||
1927 | case LM_CB_NEED_RECOVERY: | |
1928 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1929 | if (sdp->sd_recoverd_process) | |
1930 | wake_up_process(sdp->sd_recoverd_process); | |
1931 | return; | |
1932 | ||
1933 | case LM_CB_DROPLOCKS: | |
1934 | gfs2_gl_hash_clear(sdp, NO_WAIT); | |
1935 | gfs2_quota_scan(sdp); | |
1936 | return; | |
1937 | ||
1938 | default: | |
1939 | gfs2_assert_warn(sdp, 0); | |
1940 | return; | |
1941 | } | |
1942 | } | |
1943 | ||
1944 | /** | |
1945 | * gfs2_try_toss_inode - try to remove a particular inode struct from cache | |
1946 | * sdp: the filesystem | |
1947 | * inum: the inode number | |
1948 | * | |
1949 | */ | |
1950 | ||
1951 | void gfs2_try_toss_inode(struct gfs2_sbd *sdp, struct gfs2_inum *inum) | |
1952 | { | |
1953 | struct gfs2_glock *gl; | |
1954 | struct gfs2_inode *ip; | |
1955 | int error; | |
1956 | ||
1957 | error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_inode_glops, | |
1958 | NO_CREATE, &gl); | |
1959 | if (error || !gl) | |
1960 | return; | |
1961 | ||
1962 | if (!gfs2_glmutex_trylock(gl)) | |
1963 | goto out; | |
1964 | ||
1965 | ip = get_gl2ip(gl); | |
1966 | if (!ip) | |
1967 | goto out_unlock; | |
1968 | ||
1969 | if (atomic_read(&ip->i_count)) | |
1970 | goto out_unlock; | |
1971 | ||
1972 | gfs2_inode_destroy(ip); | |
1973 | ||
1974 | out_unlock: | |
1975 | gfs2_glmutex_unlock(gl); | |
1976 | ||
1977 | out: | |
1978 | gfs2_glock_put(gl); | |
1979 | } | |
1980 | ||
1981 | /** | |
1982 | * gfs2_iopen_go_callback - Try to kick the inode/vnode associated with an | |
1983 | * iopen glock from memory | |
1984 | * @io_gl: the iopen glock | |
1985 | * @state: the state into which the glock should be put | |
1986 | * | |
1987 | */ | |
1988 | ||
1989 | void gfs2_iopen_go_callback(struct gfs2_glock *io_gl, unsigned int state) | |
1990 | { | |
1991 | struct gfs2_glock *i_gl; | |
1992 | ||
1993 | if (state != LM_ST_UNLOCKED) | |
1994 | return; | |
1995 | ||
1996 | spin_lock(&io_gl->gl_spin); | |
1997 | i_gl = get_gl2gl(io_gl); | |
1998 | if (i_gl) { | |
1999 | gfs2_glock_hold(i_gl); | |
2000 | spin_unlock(&io_gl->gl_spin); | |
2001 | } else { | |
2002 | spin_unlock(&io_gl->gl_spin); | |
2003 | return; | |
2004 | } | |
2005 | ||
2006 | if (gfs2_glmutex_trylock(i_gl)) { | |
2007 | struct gfs2_inode *ip = get_gl2ip(i_gl); | |
2008 | if (ip) { | |
2009 | gfs2_try_toss_vnode(ip); | |
2010 | gfs2_glmutex_unlock(i_gl); | |
2011 | gfs2_glock_schedule_for_reclaim(i_gl); | |
2012 | goto out; | |
2013 | } | |
2014 | gfs2_glmutex_unlock(i_gl); | |
2015 | } | |
2016 | ||
2017 | out: | |
2018 | gfs2_glock_put(i_gl); | |
2019 | } | |
2020 | ||
2021 | /** | |
2022 | * demote_ok - Check to see if it's ok to unlock a glock | |
2023 | * @gl: the glock | |
2024 | * | |
2025 | * Returns: 1 if it's ok | |
2026 | */ | |
2027 | ||
2028 | static int demote_ok(struct gfs2_glock *gl) | |
2029 | { | |
2030 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
2031 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
2032 | int demote = 1; | |
2033 | ||
2034 | if (test_bit(GLF_STICKY, &gl->gl_flags)) | |
2035 | demote = 0; | |
2036 | else if (test_bit(GLF_PREFETCH, &gl->gl_flags)) | |
2037 | demote = time_after_eq(jiffies, | |
2038 | gl->gl_stamp + | |
2039 | gfs2_tune_get(sdp, gt_prefetch_secs) * HZ); | |
2040 | else if (glops->go_demote_ok) | |
2041 | demote = glops->go_demote_ok(gl); | |
2042 | ||
2043 | return demote; | |
2044 | } | |
2045 | ||
2046 | /** | |
2047 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
2048 | * @gl: the glock | |
2049 | * | |
2050 | */ | |
2051 | ||
2052 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
2053 | { | |
2054 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
2055 | ||
2056 | spin_lock(&sdp->sd_reclaim_lock); | |
2057 | if (list_empty(&gl->gl_reclaim)) { | |
2058 | gfs2_glock_hold(gl); | |
2059 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); | |
2060 | atomic_inc(&sdp->sd_reclaim_count); | |
2061 | } | |
2062 | spin_unlock(&sdp->sd_reclaim_lock); | |
2063 | ||
2064 | wake_up(&sdp->sd_reclaim_wq); | |
2065 | } | |
2066 | ||
2067 | /** | |
2068 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list | |
2069 | * @sdp: the filesystem | |
2070 | * | |
2071 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a | |
2072 | * different glock and we notice that there are a lot of glocks in the | |
2073 | * reclaim list. | |
2074 | * | |
2075 | */ | |
2076 | ||
2077 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) | |
2078 | { | |
2079 | struct gfs2_glock *gl; | |
2080 | ||
2081 | spin_lock(&sdp->sd_reclaim_lock); | |
2082 | if (list_empty(&sdp->sd_reclaim_list)) { | |
2083 | spin_unlock(&sdp->sd_reclaim_lock); | |
2084 | return; | |
2085 | } | |
2086 | gl = list_entry(sdp->sd_reclaim_list.next, | |
2087 | struct gfs2_glock, gl_reclaim); | |
2088 | list_del_init(&gl->gl_reclaim); | |
2089 | spin_unlock(&sdp->sd_reclaim_lock); | |
2090 | ||
2091 | atomic_dec(&sdp->sd_reclaim_count); | |
2092 | atomic_inc(&sdp->sd_reclaimed); | |
2093 | ||
2094 | if (gfs2_glmutex_trylock(gl)) { | |
2095 | if (gl->gl_ops == &gfs2_inode_glops) { | |
2096 | struct gfs2_inode *ip = get_gl2ip(gl); | |
2097 | if (ip && !atomic_read(&ip->i_count)) | |
2098 | gfs2_inode_destroy(ip); | |
2099 | } | |
2100 | if (queue_empty(gl, &gl->gl_holders) && | |
2101 | gl->gl_state != LM_ST_UNLOCKED && | |
2102 | demote_ok(gl)) | |
2103 | handle_callback(gl, LM_ST_UNLOCKED); | |
2104 | gfs2_glmutex_unlock(gl); | |
2105 | } | |
2106 | ||
2107 | gfs2_glock_put(gl); | |
2108 | } | |
2109 | ||
2110 | /** | |
2111 | * examine_bucket - Call a function for glock in a hash bucket | |
2112 | * @examiner: the function | |
2113 | * @sdp: the filesystem | |
2114 | * @bucket: the bucket | |
2115 | * | |
2116 | * Returns: 1 if the bucket has entries | |
2117 | */ | |
2118 | ||
2119 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
2120 | struct gfs2_gl_hash_bucket *bucket) | |
2121 | { | |
2122 | struct glock_plug plug; | |
2123 | struct list_head *tmp; | |
2124 | struct gfs2_glock *gl; | |
2125 | int entries; | |
2126 | ||
2127 | /* Add "plug" to end of bucket list, work back up list from there */ | |
2128 | memset(&plug.gl_flags, 0, sizeof(unsigned long)); | |
2129 | set_bit(GLF_PLUG, &plug.gl_flags); | |
2130 | ||
2131 | write_lock(&bucket->hb_lock); | |
2132 | list_add(&plug.gl_list, &bucket->hb_list); | |
2133 | write_unlock(&bucket->hb_lock); | |
2134 | ||
2135 | for (;;) { | |
2136 | write_lock(&bucket->hb_lock); | |
2137 | ||
2138 | for (;;) { | |
2139 | tmp = plug.gl_list.next; | |
2140 | ||
2141 | if (tmp == &bucket->hb_list) { | |
2142 | list_del(&plug.gl_list); | |
2143 | entries = !list_empty(&bucket->hb_list); | |
2144 | write_unlock(&bucket->hb_lock); | |
2145 | return entries; | |
2146 | } | |
2147 | gl = list_entry(tmp, struct gfs2_glock, gl_list); | |
2148 | ||
2149 | /* Move plug up list */ | |
2150 | list_move(&plug.gl_list, &gl->gl_list); | |
2151 | ||
2152 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
2153 | continue; | |
2154 | ||
2155 | /* examiner() must glock_put() */ | |
2156 | gfs2_glock_hold(gl); | |
2157 | ||
2158 | break; | |
2159 | } | |
2160 | ||
2161 | write_unlock(&bucket->hb_lock); | |
2162 | ||
2163 | examiner(gl); | |
2164 | } | |
2165 | } | |
2166 | ||
2167 | /** | |
2168 | * scan_glock - look at a glock and see if we can reclaim it | |
2169 | * @gl: the glock to look at | |
2170 | * | |
2171 | */ | |
2172 | ||
2173 | static void scan_glock(struct gfs2_glock *gl) | |
2174 | { | |
2175 | if (gfs2_glmutex_trylock(gl)) { | |
2176 | if (gl->gl_ops == &gfs2_inode_glops) { | |
2177 | struct gfs2_inode *ip = get_gl2ip(gl); | |
2178 | if (ip && !atomic_read(&ip->i_count)) | |
2179 | goto out_schedule; | |
2180 | } | |
2181 | if (queue_empty(gl, &gl->gl_holders) && | |
2182 | gl->gl_state != LM_ST_UNLOCKED && | |
2183 | demote_ok(gl)) | |
2184 | goto out_schedule; | |
2185 | ||
2186 | gfs2_glmutex_unlock(gl); | |
2187 | } | |
2188 | ||
2189 | gfs2_glock_put(gl); | |
2190 | ||
2191 | return; | |
2192 | ||
2193 | out_schedule: | |
2194 | gfs2_glmutex_unlock(gl); | |
2195 | gfs2_glock_schedule_for_reclaim(gl); | |
2196 | gfs2_glock_put(gl); | |
2197 | } | |
2198 | ||
2199 | /** | |
2200 | * gfs2_scand_internal - Look for glocks and inodes to toss from memory | |
2201 | * @sdp: the filesystem | |
2202 | * | |
2203 | */ | |
2204 | ||
2205 | void gfs2_scand_internal(struct gfs2_sbd *sdp) | |
2206 | { | |
2207 | unsigned int x; | |
2208 | ||
2209 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2210 | examine_bucket(scan_glock, sdp, &sdp->sd_gl_hash[x]); | |
2211 | cond_resched(); | |
2212 | } | |
2213 | } | |
2214 | ||
2215 | /** | |
2216 | * clear_glock - look at a glock and see if we can free it from glock cache | |
2217 | * @gl: the glock to look at | |
2218 | * | |
2219 | */ | |
2220 | ||
2221 | static void clear_glock(struct gfs2_glock *gl) | |
2222 | { | |
2223 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
2224 | int released; | |
2225 | ||
2226 | spin_lock(&sdp->sd_reclaim_lock); | |
2227 | if (!list_empty(&gl->gl_reclaim)) { | |
2228 | list_del_init(&gl->gl_reclaim); | |
2229 | atomic_dec(&sdp->sd_reclaim_count); | |
2230 | released = gfs2_glock_put(gl); | |
2231 | gfs2_assert(sdp, !released); | |
2232 | } | |
2233 | spin_unlock(&sdp->sd_reclaim_lock); | |
2234 | ||
2235 | if (gfs2_glmutex_trylock(gl)) { | |
2236 | if (gl->gl_ops == &gfs2_inode_glops) { | |
2237 | struct gfs2_inode *ip = get_gl2ip(gl); | |
2238 | if (ip && !atomic_read(&ip->i_count)) | |
2239 | gfs2_inode_destroy(ip); | |
2240 | } | |
2241 | if (queue_empty(gl, &gl->gl_holders) && | |
2242 | gl->gl_state != LM_ST_UNLOCKED) | |
2243 | handle_callback(gl, LM_ST_UNLOCKED); | |
2244 | ||
2245 | gfs2_glmutex_unlock(gl); | |
2246 | } | |
2247 | ||
2248 | gfs2_glock_put(gl); | |
2249 | } | |
2250 | ||
2251 | /** | |
2252 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
2253 | * @sdp: the filesystem | |
2254 | * @wait: wait until it's all gone | |
2255 | * | |
2256 | * Called when unmounting the filesystem, or when inter-node lock manager | |
2257 | * requests DROPLOCKS because it is running out of capacity. | |
2258 | */ | |
2259 | ||
2260 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) | |
2261 | { | |
2262 | unsigned long t; | |
2263 | unsigned int x; | |
2264 | int cont; | |
2265 | ||
2266 | t = jiffies; | |
2267 | ||
2268 | for (;;) { | |
2269 | cont = 0; | |
2270 | ||
2271 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
2272 | if (examine_bucket(clear_glock, sdp, | |
2273 | &sdp->sd_gl_hash[x])) | |
2274 | cont = 1; | |
2275 | ||
2276 | if (!wait || !cont) | |
2277 | break; | |
2278 | ||
2279 | if (time_after_eq(jiffies, | |
2280 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
2281 | fs_warn(sdp, "Unmount seems to be stalled. " | |
2282 | "Dumping lock state...\n"); | |
2283 | gfs2_dump_lockstate(sdp); | |
2284 | t = jiffies; | |
2285 | } | |
2286 | ||
2287 | /* invalidate_inodes() requires that the sb inodes list | |
2288 | not change, but an async completion callback for an | |
2289 | unlock can occur which does glock_put() which | |
2290 | can call iput() which will change the sb inodes list. | |
2291 | invalidate_inodes_mutex prevents glock_put()'s during | |
2292 | an invalidate_inodes() */ | |
2293 | ||
f55ab26a | 2294 | mutex_lock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa | 2295 | invalidate_inodes(sdp->sd_vfs); |
f55ab26a | 2296 | mutex_unlock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa DT |
2297 | yield(); |
2298 | } | |
2299 | } | |
2300 | ||
2301 | /* | |
2302 | * Diagnostic routines to help debug distributed deadlock | |
2303 | */ | |
2304 | ||
2305 | /** | |
2306 | * dump_holder - print information about a glock holder | |
2307 | * @str: a string naming the type of holder | |
2308 | * @gh: the glock holder | |
2309 | * | |
2310 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2311 | */ | |
2312 | ||
2313 | static int dump_holder(char *str, struct gfs2_holder *gh) | |
2314 | { | |
2315 | unsigned int x; | |
2316 | int error = -ENOBUFS; | |
2317 | ||
d92a8d48 SW |
2318 | printk(KERN_INFO " %s\n", str); |
2319 | printk(KERN_INFO " owner = %ld\n", | |
b3b94faa | 2320 | (gh->gh_owner) ? (long)gh->gh_owner->pid : -1); |
d92a8d48 SW |
2321 | printk(KERN_INFO " gh_state = %u\n", gh->gh_state); |
2322 | printk(KERN_INFO " gh_flags ="); | |
b3b94faa DT |
2323 | for (x = 0; x < 32; x++) |
2324 | if (gh->gh_flags & (1 << x)) | |
2325 | printk(" %u", x); | |
2326 | printk(" \n"); | |
d92a8d48 SW |
2327 | printk(KERN_INFO " error = %d\n", gh->gh_error); |
2328 | printk(KERN_INFO " gh_iflags ="); | |
b3b94faa DT |
2329 | for (x = 0; x < 32; x++) |
2330 | if (test_bit(x, &gh->gh_iflags)) | |
2331 | printk(" %u", x); | |
2332 | printk(" \n"); | |
2333 | ||
2334 | error = 0; | |
2335 | ||
2336 | return error; | |
2337 | } | |
2338 | ||
2339 | /** | |
2340 | * dump_inode - print information about an inode | |
2341 | * @ip: the inode | |
2342 | * | |
2343 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2344 | */ | |
2345 | ||
2346 | static int dump_inode(struct gfs2_inode *ip) | |
2347 | { | |
2348 | unsigned int x; | |
2349 | int error = -ENOBUFS; | |
2350 | ||
d92a8d48 SW |
2351 | printk(KERN_INFO " Inode:\n"); |
2352 | printk(KERN_INFO " num = %llu %llu\n", | |
b3b94faa | 2353 | ip->i_num.no_formal_ino, ip->i_num.no_addr); |
d92a8d48 SW |
2354 | printk(KERN_INFO " type = %u\n", IF2DT(ip->i_di.di_mode)); |
2355 | printk(KERN_INFO " i_count = %d\n", atomic_read(&ip->i_count)); | |
2356 | printk(KERN_INFO " i_flags ="); | |
b3b94faa DT |
2357 | for (x = 0; x < 32; x++) |
2358 | if (test_bit(x, &ip->i_flags)) | |
2359 | printk(" %u", x); | |
2360 | printk(" \n"); | |
d92a8d48 | 2361 | printk(KERN_INFO " vnode = %s\n", (ip->i_vnode) ? "yes" : "no"); |
b3b94faa DT |
2362 | |
2363 | error = 0; | |
2364 | ||
2365 | return error; | |
2366 | } | |
2367 | ||
2368 | /** | |
2369 | * dump_glock - print information about a glock | |
2370 | * @gl: the glock | |
2371 | * @count: where we are in the buffer | |
2372 | * | |
2373 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2374 | */ | |
2375 | ||
2376 | static int dump_glock(struct gfs2_glock *gl) | |
2377 | { | |
2378 | struct gfs2_holder *gh; | |
2379 | unsigned int x; | |
2380 | int error = -ENOBUFS; | |
2381 | ||
2382 | spin_lock(&gl->gl_spin); | |
2383 | ||
d92a8d48 | 2384 | printk(KERN_INFO "Glock (%u, %llu)\n", |
b3b94faa DT |
2385 | gl->gl_name.ln_type, |
2386 | gl->gl_name.ln_number); | |
d92a8d48 | 2387 | printk(KERN_INFO " gl_flags ="); |
b3b94faa DT |
2388 | for (x = 0; x < 32; x++) |
2389 | if (test_bit(x, &gl->gl_flags)) | |
2390 | printk(" %u", x); | |
2391 | printk(" \n"); | |
d92a8d48 SW |
2392 | printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref.refcount)); |
2393 | printk(KERN_INFO " gl_state = %u\n", gl->gl_state); | |
2394 | printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); | |
2395 | printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); | |
2396 | printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); | |
2397 | printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no"); | |
2398 | printk(KERN_INFO " le = %s\n", | |
b3b94faa | 2399 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
d92a8d48 | 2400 | printk(KERN_INFO " reclaim = %s\n", |
b3b94faa DT |
2401 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); |
2402 | if (gl->gl_aspace) | |
d92a8d48 | 2403 | printk(KERN_INFO " aspace = %lu\n", |
b3b94faa DT |
2404 | gl->gl_aspace->i_mapping->nrpages); |
2405 | else | |
d92a8d48 SW |
2406 | printk(KERN_INFO " aspace = no\n"); |
2407 | printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count)); | |
b3b94faa DT |
2408 | if (gl->gl_req_gh) { |
2409 | error = dump_holder("Request", gl->gl_req_gh); | |
2410 | if (error) | |
2411 | goto out; | |
2412 | } | |
2413 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
2414 | error = dump_holder("Holder", gh); | |
2415 | if (error) | |
2416 | goto out; | |
2417 | } | |
2418 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { | |
2419 | error = dump_holder("Waiter1", gh); | |
2420 | if (error) | |
2421 | goto out; | |
2422 | } | |
2423 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
2424 | error = dump_holder("Waiter2", gh); | |
2425 | if (error) | |
2426 | goto out; | |
2427 | } | |
2428 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { | |
2429 | error = dump_holder("Waiter3", gh); | |
2430 | if (error) | |
2431 | goto out; | |
2432 | } | |
2433 | if (gl->gl_ops == &gfs2_inode_glops && get_gl2ip(gl)) { | |
2434 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && | |
2435 | list_empty(&gl->gl_holders)) { | |
2436 | error = dump_inode(get_gl2ip(gl)); | |
2437 | if (error) | |
2438 | goto out; | |
2439 | } else { | |
2440 | error = -ENOBUFS; | |
d92a8d48 | 2441 | printk(KERN_INFO " Inode: busy\n"); |
b3b94faa DT |
2442 | } |
2443 | } | |
2444 | ||
2445 | error = 0; | |
2446 | ||
2447 | out: | |
2448 | spin_unlock(&gl->gl_spin); | |
2449 | ||
2450 | return error; | |
2451 | } | |
2452 | ||
2453 | /** | |
2454 | * gfs2_dump_lockstate - print out the current lockstate | |
2455 | * @sdp: the filesystem | |
2456 | * @ub: the buffer to copy the information into | |
2457 | * | |
2458 | * If @ub is NULL, dump the lockstate to the console. | |
2459 | * | |
2460 | */ | |
2461 | ||
2462 | int gfs2_dump_lockstate(struct gfs2_sbd *sdp) | |
2463 | { | |
2464 | struct gfs2_gl_hash_bucket *bucket; | |
2465 | struct gfs2_glock *gl; | |
2466 | unsigned int x; | |
2467 | int error = 0; | |
2468 | ||
2469 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2470 | bucket = &sdp->sd_gl_hash[x]; | |
2471 | ||
2472 | read_lock(&bucket->hb_lock); | |
2473 | ||
2474 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
2475 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
2476 | continue; | |
2477 | ||
2478 | error = dump_glock(gl); | |
2479 | if (error) | |
2480 | break; | |
2481 | } | |
2482 | ||
2483 | read_unlock(&bucket->hb_lock); | |
2484 | ||
2485 | if (error) | |
2486 | break; | |
2487 | } | |
2488 | ||
2489 | ||
2490 | return error; | |
2491 | } | |
2492 |