Commit | Line | Data |
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b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
3a8a9a10 | 3 | * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
b3b94faa DT |
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> | |
d0dc80db | 19 | #include <linux/kallsyms.h> |
5c676f6d | 20 | #include <linux/gfs2_ondisk.h> |
b3b94faa DT |
21 | #include <asm/uaccess.h> |
22 | ||
23 | #include "gfs2.h" | |
5c676f6d SW |
24 | #include "lm_interface.h" |
25 | #include "incore.h" | |
b3b94faa DT |
26 | #include "glock.h" |
27 | #include "glops.h" | |
28 | #include "inode.h" | |
29 | #include "lm.h" | |
30 | #include "lops.h" | |
31 | #include "meta_io.h" | |
32 | #include "quota.h" | |
33 | #include "super.h" | |
5c676f6d | 34 | #include "util.h" |
b3b94faa DT |
35 | |
36 | /* Must be kept in sync with the beginning of struct gfs2_glock */ | |
37 | struct glock_plug { | |
38 | struct list_head gl_list; | |
39 | unsigned long gl_flags; | |
40 | }; | |
41 | ||
42 | struct greedy { | |
43 | struct gfs2_holder gr_gh; | |
44 | struct work_struct gr_work; | |
45 | }; | |
46 | ||
47 | typedef void (*glock_examiner) (struct gfs2_glock * gl); | |
48 | ||
08bc2dbc | 49 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); |
320dd101 | 50 | static int dump_glock(struct gfs2_glock *gl); |
08bc2dbc | 51 | |
b3b94faa DT |
52 | /** |
53 | * relaxed_state_ok - is a requested lock compatible with the current lock mode? | |
54 | * @actual: the current state of the lock | |
55 | * @requested: the lock state that was requested by the caller | |
56 | * @flags: the modifier flags passed in by the caller | |
57 | * | |
58 | * Returns: 1 if the locks are compatible, 0 otherwise | |
59 | */ | |
60 | ||
61 | static inline int relaxed_state_ok(unsigned int actual, unsigned requested, | |
62 | int flags) | |
63 | { | |
64 | if (actual == requested) | |
65 | return 1; | |
66 | ||
67 | if (flags & GL_EXACT) | |
68 | return 0; | |
69 | ||
70 | if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED) | |
71 | return 1; | |
72 | ||
73 | if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY)) | |
74 | return 1; | |
75 | ||
76 | return 0; | |
77 | } | |
78 | ||
79 | /** | |
80 | * gl_hash() - Turn glock number into hash bucket number | |
81 | * @lock: The glock number | |
82 | * | |
83 | * Returns: The number of the corresponding hash bucket | |
84 | */ | |
85 | ||
86 | static unsigned int gl_hash(struct lm_lockname *name) | |
87 | { | |
88 | unsigned int h; | |
89 | ||
90 | h = jhash(&name->ln_number, sizeof(uint64_t), 0); | |
91 | h = jhash(&name->ln_type, sizeof(unsigned int), h); | |
92 | h &= GFS2_GL_HASH_MASK; | |
93 | ||
94 | return h; | |
95 | } | |
96 | ||
97 | /** | |
98 | * glock_free() - Perform a few checks and then release struct gfs2_glock | |
99 | * @gl: The glock to release | |
100 | * | |
101 | * Also calls lock module to release its internal structure for this glock. | |
102 | * | |
103 | */ | |
104 | ||
105 | static void glock_free(struct gfs2_glock *gl) | |
106 | { | |
107 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
108 | struct inode *aspace = gl->gl_aspace; | |
109 | ||
110 | gfs2_lm_put_lock(sdp, gl->gl_lock); | |
111 | ||
112 | if (aspace) | |
113 | gfs2_aspace_put(aspace); | |
114 | ||
115 | kmem_cache_free(gfs2_glock_cachep, gl); | |
b3b94faa DT |
116 | } |
117 | ||
118 | /** | |
119 | * gfs2_glock_hold() - increment reference count on glock | |
120 | * @gl: The glock to hold | |
121 | * | |
122 | */ | |
123 | ||
124 | void gfs2_glock_hold(struct gfs2_glock *gl) | |
125 | { | |
126 | kref_get(&gl->gl_ref); | |
127 | } | |
128 | ||
129 | /* All work is done after the return from kref_put() so we | |
130 | can release the write_lock before the free. */ | |
131 | ||
132 | static void kill_glock(struct kref *kref) | |
133 | { | |
134 | struct gfs2_glock *gl = container_of(kref, struct gfs2_glock, gl_ref); | |
135 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
136 | ||
137 | gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED); | |
138 | gfs2_assert(sdp, list_empty(&gl->gl_reclaim)); | |
139 | gfs2_assert(sdp, list_empty(&gl->gl_holders)); | |
140 | gfs2_assert(sdp, list_empty(&gl->gl_waiters1)); | |
141 | gfs2_assert(sdp, list_empty(&gl->gl_waiters2)); | |
142 | gfs2_assert(sdp, list_empty(&gl->gl_waiters3)); | |
143 | } | |
144 | ||
145 | /** | |
146 | * gfs2_glock_put() - Decrement reference count on glock | |
147 | * @gl: The glock to put | |
148 | * | |
149 | */ | |
150 | ||
151 | int gfs2_glock_put(struct gfs2_glock *gl) | |
152 | { | |
153 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
154 | struct gfs2_gl_hash_bucket *bucket = gl->gl_bucket; | |
155 | int rv = 0; | |
156 | ||
f55ab26a | 157 | mutex_lock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa DT |
158 | |
159 | write_lock(&bucket->hb_lock); | |
160 | if (kref_put(&gl->gl_ref, kill_glock)) { | |
161 | list_del_init(&gl->gl_list); | |
162 | write_unlock(&bucket->hb_lock); | |
190562bd | 163 | BUG_ON(spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
164 | glock_free(gl); |
165 | rv = 1; | |
166 | goto out; | |
167 | } | |
168 | write_unlock(&bucket->hb_lock); | |
169 | out: | |
f55ab26a | 170 | mutex_unlock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa DT |
171 | return rv; |
172 | } | |
173 | ||
174 | /** | |
175 | * queue_empty - check to see if a glock's queue is empty | |
176 | * @gl: the glock | |
177 | * @head: the head of the queue to check | |
178 | * | |
179 | * This function protects the list in the event that a process already | |
180 | * has a holder on the list and is adding a second holder for itself. | |
181 | * The glmutex lock is what generally prevents processes from working | |
182 | * on the same glock at once, but the special case of adding a second | |
183 | * holder for yourself ("recursive" locking) doesn't involve locking | |
184 | * glmutex, making the spin lock necessary. | |
185 | * | |
186 | * Returns: 1 if the queue is empty | |
187 | */ | |
188 | ||
189 | static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head) | |
190 | { | |
191 | int empty; | |
192 | spin_lock(&gl->gl_spin); | |
193 | empty = list_empty(head); | |
194 | spin_unlock(&gl->gl_spin); | |
195 | return empty; | |
196 | } | |
197 | ||
198 | /** | |
199 | * search_bucket() - Find struct gfs2_glock by lock number | |
200 | * @bucket: the bucket to search | |
201 | * @name: The lock name | |
202 | * | |
203 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
204 | */ | |
205 | ||
206 | static struct gfs2_glock *search_bucket(struct gfs2_gl_hash_bucket *bucket, | |
207 | struct lm_lockname *name) | |
208 | { | |
209 | struct gfs2_glock *gl; | |
210 | ||
211 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
212 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
213 | continue; | |
214 | if (!lm_name_equal(&gl->gl_name, name)) | |
215 | continue; | |
216 | ||
217 | kref_get(&gl->gl_ref); | |
218 | ||
219 | return gl; | |
220 | } | |
221 | ||
222 | return NULL; | |
223 | } | |
224 | ||
225 | /** | |
226 | * gfs2_glock_find() - Find glock by lock number | |
227 | * @sdp: The GFS2 superblock | |
228 | * @name: The lock name | |
229 | * | |
230 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
231 | */ | |
232 | ||
08bc2dbc AB |
233 | static struct gfs2_glock *gfs2_glock_find(struct gfs2_sbd *sdp, |
234 | struct lm_lockname *name) | |
b3b94faa DT |
235 | { |
236 | struct gfs2_gl_hash_bucket *bucket = &sdp->sd_gl_hash[gl_hash(name)]; | |
237 | struct gfs2_glock *gl; | |
238 | ||
239 | read_lock(&bucket->hb_lock); | |
240 | gl = search_bucket(bucket, name); | |
241 | read_unlock(&bucket->hb_lock); | |
242 | ||
243 | return gl; | |
244 | } | |
245 | ||
246 | /** | |
247 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
248 | * @sdp: The GFS2 superblock | |
249 | * @number: the lock number | |
250 | * @glops: The glock_operations to use | |
251 | * @create: If 0, don't create the glock if it doesn't exist | |
252 | * @glp: the glock is returned here | |
253 | * | |
254 | * This does not lock a glock, just finds/creates structures for one. | |
255 | * | |
256 | * Returns: errno | |
257 | */ | |
258 | ||
259 | int gfs2_glock_get(struct gfs2_sbd *sdp, uint64_t number, | |
260 | struct gfs2_glock_operations *glops, int create, | |
261 | struct gfs2_glock **glp) | |
262 | { | |
263 | struct lm_lockname name; | |
264 | struct gfs2_glock *gl, *tmp; | |
265 | struct gfs2_gl_hash_bucket *bucket; | |
266 | int error; | |
267 | ||
268 | name.ln_number = number; | |
269 | name.ln_type = glops->go_type; | |
270 | bucket = &sdp->sd_gl_hash[gl_hash(&name)]; | |
271 | ||
272 | read_lock(&bucket->hb_lock); | |
273 | gl = search_bucket(bucket, &name); | |
274 | read_unlock(&bucket->hb_lock); | |
275 | ||
276 | if (gl || !create) { | |
277 | *glp = gl; | |
278 | return 0; | |
279 | } | |
280 | ||
281 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); | |
282 | if (!gl) | |
283 | return -ENOMEM; | |
284 | ||
285 | memset(gl, 0, sizeof(struct gfs2_glock)); | |
286 | ||
287 | INIT_LIST_HEAD(&gl->gl_list); | |
288 | gl->gl_name = name; | |
289 | kref_init(&gl->gl_ref); | |
290 | ||
291 | spin_lock_init(&gl->gl_spin); | |
292 | ||
293 | gl->gl_state = LM_ST_UNLOCKED; | |
320dd101 SW |
294 | gl->gl_owner = NULL; |
295 | gl->gl_ip = 0; | |
b3b94faa DT |
296 | INIT_LIST_HEAD(&gl->gl_holders); |
297 | INIT_LIST_HEAD(&gl->gl_waiters1); | |
298 | INIT_LIST_HEAD(&gl->gl_waiters2); | |
299 | INIT_LIST_HEAD(&gl->gl_waiters3); | |
300 | ||
301 | gl->gl_ops = glops; | |
302 | ||
303 | gl->gl_bucket = bucket; | |
304 | INIT_LIST_HEAD(&gl->gl_reclaim); | |
305 | ||
306 | gl->gl_sbd = sdp; | |
307 | ||
308 | lops_init_le(&gl->gl_le, &gfs2_glock_lops); | |
309 | INIT_LIST_HEAD(&gl->gl_ail_list); | |
310 | ||
311 | /* If this glock protects actual on-disk data or metadata blocks, | |
312 | create a VFS inode to manage the pages/buffers holding them. */ | |
313 | if (glops == &gfs2_inode_glops || | |
314 | glops == &gfs2_rgrp_glops || | |
315 | glops == &gfs2_meta_glops) { | |
316 | gl->gl_aspace = gfs2_aspace_get(sdp); | |
317 | if (!gl->gl_aspace) { | |
318 | error = -ENOMEM; | |
319 | goto fail; | |
320 | } | |
321 | } | |
322 | ||
323 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
324 | if (error) | |
325 | goto fail_aspace; | |
326 | ||
b3b94faa DT |
327 | write_lock(&bucket->hb_lock); |
328 | tmp = search_bucket(bucket, &name); | |
329 | if (tmp) { | |
330 | write_unlock(&bucket->hb_lock); | |
331 | glock_free(gl); | |
332 | gl = tmp; | |
333 | } else { | |
334 | list_add_tail(&gl->gl_list, &bucket->hb_list); | |
335 | write_unlock(&bucket->hb_lock); | |
336 | } | |
337 | ||
338 | *glp = gl; | |
339 | ||
340 | return 0; | |
341 | ||
342 | fail_aspace: | |
343 | if (gl->gl_aspace) | |
344 | gfs2_aspace_put(gl->gl_aspace); | |
345 | ||
346 | fail: | |
347 | kmem_cache_free(gfs2_glock_cachep, gl); | |
348 | ||
349 | return error; | |
350 | } | |
351 | ||
352 | /** | |
353 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
354 | * @gl: the glock | |
355 | * @state: the state we're requesting | |
356 | * @flags: the modifier flags | |
357 | * @gh: the holder structure | |
358 | * | |
359 | */ | |
360 | ||
190562bd | 361 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
362 | struct gfs2_holder *gh) |
363 | { | |
364 | INIT_LIST_HEAD(&gh->gh_list); | |
365 | gh->gh_gl = gl; | |
d0dc80db | 366 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
190562bd | 367 | gh->gh_owner = current; |
b3b94faa DT |
368 | gh->gh_state = state; |
369 | gh->gh_flags = flags; | |
370 | gh->gh_error = 0; | |
371 | gh->gh_iflags = 0; | |
372 | init_completion(&gh->gh_wait); | |
373 | ||
374 | if (gh->gh_state == LM_ST_EXCLUSIVE) | |
375 | gh->gh_flags |= GL_LOCAL_EXCL; | |
376 | ||
377 | gfs2_glock_hold(gl); | |
378 | } | |
379 | ||
380 | /** | |
381 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
382 | * @state: the state we're requesting | |
383 | * @flags: the modifier flags | |
384 | * @gh: the holder structure | |
385 | * | |
386 | * Don't mess with the glock. | |
387 | * | |
388 | */ | |
389 | ||
190562bd | 390 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
391 | { |
392 | gh->gh_state = state; | |
579b78a4 | 393 | gh->gh_flags = flags; |
b3b94faa DT |
394 | if (gh->gh_state == LM_ST_EXCLUSIVE) |
395 | gh->gh_flags |= GL_LOCAL_EXCL; | |
396 | ||
397 | gh->gh_iflags &= 1 << HIF_ALLOCED; | |
d0dc80db | 398 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
399 | } |
400 | ||
401 | /** | |
402 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
403 | * @gh: the holder structure | |
404 | * | |
405 | */ | |
406 | ||
407 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
408 | { | |
409 | gfs2_glock_put(gh->gh_gl); | |
410 | gh->gh_gl = NULL; | |
d0dc80db | 411 | gh->gh_ip = 0; |
b3b94faa DT |
412 | } |
413 | ||
414 | /** | |
415 | * gfs2_holder_get - get a struct gfs2_holder structure | |
416 | * @gl: the glock | |
417 | * @state: the state we're requesting | |
418 | * @flags: the modifier flags | |
419 | * @gfp_flags: __GFP_NOFAIL | |
420 | * | |
421 | * Figure out how big an impact this function has. Either: | |
422 | * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd | |
423 | * 2) Leave it like it is | |
424 | * | |
425 | * Returns: the holder structure, NULL on ENOMEM | |
426 | */ | |
427 | ||
08bc2dbc AB |
428 | static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, |
429 | unsigned int state, | |
430 | int flags, gfp_t gfp_flags) | |
b3b94faa DT |
431 | { |
432 | struct gfs2_holder *gh; | |
433 | ||
434 | gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags); | |
435 | if (!gh) | |
436 | return NULL; | |
437 | ||
438 | gfs2_holder_init(gl, state, flags, gh); | |
439 | set_bit(HIF_ALLOCED, &gh->gh_iflags); | |
d0dc80db | 440 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
441 | return gh; |
442 | } | |
443 | ||
444 | /** | |
445 | * gfs2_holder_put - get rid of a struct gfs2_holder structure | |
446 | * @gh: the holder structure | |
447 | * | |
448 | */ | |
449 | ||
08bc2dbc | 450 | static void gfs2_holder_put(struct gfs2_holder *gh) |
b3b94faa DT |
451 | { |
452 | gfs2_holder_uninit(gh); | |
453 | kfree(gh); | |
454 | } | |
455 | ||
b3b94faa DT |
456 | /** |
457 | * rq_mutex - process a mutex request in the queue | |
458 | * @gh: the glock holder | |
459 | * | |
460 | * Returns: 1 if the queue is blocked | |
461 | */ | |
462 | ||
463 | static int rq_mutex(struct gfs2_holder *gh) | |
464 | { | |
465 | struct gfs2_glock *gl = gh->gh_gl; | |
466 | ||
467 | list_del_init(&gh->gh_list); | |
468 | /* gh->gh_error never examined. */ | |
469 | set_bit(GLF_LOCK, &gl->gl_flags); | |
470 | complete(&gh->gh_wait); | |
471 | ||
472 | return 1; | |
473 | } | |
474 | ||
475 | /** | |
476 | * rq_promote - process a promote request in the queue | |
477 | * @gh: the glock holder | |
478 | * | |
479 | * Acquire a new inter-node lock, or change a lock state to more restrictive. | |
480 | * | |
481 | * Returns: 1 if the queue is blocked | |
482 | */ | |
483 | ||
484 | static int rq_promote(struct gfs2_holder *gh) | |
485 | { | |
486 | struct gfs2_glock *gl = gh->gh_gl; | |
487 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
488 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
b3b94faa DT |
489 | |
490 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
491 | if (list_empty(&gl->gl_holders)) { | |
492 | gl->gl_req_gh = gh; | |
493 | set_bit(GLF_LOCK, &gl->gl_flags); | |
494 | spin_unlock(&gl->gl_spin); | |
495 | ||
496 | if (atomic_read(&sdp->sd_reclaim_count) > | |
497 | gfs2_tune_get(sdp, gt_reclaim_limit) && | |
498 | !(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
499 | gfs2_reclaim_glock(sdp); | |
500 | gfs2_reclaim_glock(sdp); | |
501 | } | |
502 | ||
503 | glops->go_xmote_th(gl, gh->gh_state, | |
504 | gh->gh_flags); | |
505 | ||
506 | spin_lock(&gl->gl_spin); | |
507 | } | |
508 | return 1; | |
509 | } | |
510 | ||
511 | if (list_empty(&gl->gl_holders)) { | |
512 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
513 | set_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
514 | } else { |
515 | struct gfs2_holder *next_gh; | |
516 | if (gh->gh_flags & GL_LOCAL_EXCL) | |
517 | return 1; | |
518 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, | |
519 | gh_list); | |
520 | if (next_gh->gh_flags & GL_LOCAL_EXCL) | |
521 | return 1; | |
b3b94faa DT |
522 | } |
523 | ||
524 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
525 | gh->gh_error = 0; | |
526 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
527 | ||
b3b94faa DT |
528 | complete(&gh->gh_wait); |
529 | ||
530 | return 0; | |
531 | } | |
532 | ||
533 | /** | |
534 | * rq_demote - process a demote request in the queue | |
535 | * @gh: the glock holder | |
536 | * | |
537 | * Returns: 1 if the queue is blocked | |
538 | */ | |
539 | ||
540 | static int rq_demote(struct gfs2_holder *gh) | |
541 | { | |
542 | struct gfs2_glock *gl = gh->gh_gl; | |
543 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
544 | ||
545 | if (!list_empty(&gl->gl_holders)) | |
546 | return 1; | |
547 | ||
548 | if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { | |
549 | list_del_init(&gh->gh_list); | |
550 | gh->gh_error = 0; | |
551 | spin_unlock(&gl->gl_spin); | |
552 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
553 | gfs2_holder_put(gh); | |
554 | else | |
555 | complete(&gh->gh_wait); | |
556 | spin_lock(&gl->gl_spin); | |
557 | } else { | |
558 | gl->gl_req_gh = gh; | |
559 | set_bit(GLF_LOCK, &gl->gl_flags); | |
560 | spin_unlock(&gl->gl_spin); | |
561 | ||
562 | if (gh->gh_state == LM_ST_UNLOCKED || | |
563 | gl->gl_state != LM_ST_EXCLUSIVE) | |
564 | glops->go_drop_th(gl); | |
565 | else | |
566 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); | |
567 | ||
568 | spin_lock(&gl->gl_spin); | |
569 | } | |
570 | ||
571 | return 0; | |
572 | } | |
573 | ||
574 | /** | |
575 | * rq_greedy - process a queued request to drop greedy status | |
576 | * @gh: the glock holder | |
577 | * | |
578 | * Returns: 1 if the queue is blocked | |
579 | */ | |
580 | ||
581 | static int rq_greedy(struct gfs2_holder *gh) | |
582 | { | |
583 | struct gfs2_glock *gl = gh->gh_gl; | |
584 | ||
585 | list_del_init(&gh->gh_list); | |
586 | /* gh->gh_error never examined. */ | |
587 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
588 | spin_unlock(&gl->gl_spin); | |
589 | ||
590 | gfs2_holder_uninit(gh); | |
591 | kfree(container_of(gh, struct greedy, gr_gh)); | |
592 | ||
593 | spin_lock(&gl->gl_spin); | |
594 | ||
595 | return 0; | |
596 | } | |
597 | ||
598 | /** | |
599 | * run_queue - process holder structures on a glock | |
600 | * @gl: the glock | |
601 | * | |
602 | */ | |
b3b94faa DT |
603 | static void run_queue(struct gfs2_glock *gl) |
604 | { | |
605 | struct gfs2_holder *gh; | |
606 | int blocked = 1; | |
607 | ||
608 | for (;;) { | |
609 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
610 | break; | |
611 | ||
612 | if (!list_empty(&gl->gl_waiters1)) { | |
613 | gh = list_entry(gl->gl_waiters1.next, | |
614 | struct gfs2_holder, gh_list); | |
615 | ||
616 | if (test_bit(HIF_MUTEX, &gh->gh_iflags)) | |
617 | blocked = rq_mutex(gh); | |
618 | else | |
619 | gfs2_assert_warn(gl->gl_sbd, 0); | |
620 | ||
621 | } else if (!list_empty(&gl->gl_waiters2) && | |
622 | !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { | |
623 | gh = list_entry(gl->gl_waiters2.next, | |
624 | struct gfs2_holder, gh_list); | |
625 | ||
626 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) | |
627 | blocked = rq_demote(gh); | |
628 | else if (test_bit(HIF_GREEDY, &gh->gh_iflags)) | |
629 | blocked = rq_greedy(gh); | |
630 | else | |
631 | gfs2_assert_warn(gl->gl_sbd, 0); | |
632 | ||
633 | } else if (!list_empty(&gl->gl_waiters3)) { | |
634 | gh = list_entry(gl->gl_waiters3.next, | |
635 | struct gfs2_holder, gh_list); | |
636 | ||
637 | if (test_bit(HIF_PROMOTE, &gh->gh_iflags)) | |
638 | blocked = rq_promote(gh); | |
639 | else | |
640 | gfs2_assert_warn(gl->gl_sbd, 0); | |
641 | ||
642 | } else | |
643 | break; | |
644 | ||
645 | if (blocked) | |
646 | break; | |
647 | } | |
648 | } | |
649 | ||
650 | /** | |
651 | * gfs2_glmutex_lock - acquire a local lock on a glock | |
652 | * @gl: the glock | |
653 | * | |
654 | * Gives caller exclusive access to manipulate a glock structure. | |
655 | */ | |
656 | ||
feaa7bba | 657 | static void gfs2_glmutex_lock(struct gfs2_glock *gl) |
b3b94faa DT |
658 | { |
659 | struct gfs2_holder gh; | |
660 | ||
661 | gfs2_holder_init(gl, 0, 0, &gh); | |
662 | set_bit(HIF_MUTEX, &gh.gh_iflags); | |
663 | ||
664 | spin_lock(&gl->gl_spin); | |
665 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
666 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); | |
320dd101 SW |
667 | else { |
668 | gl->gl_owner = current; | |
669 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
b3b94faa | 670 | complete(&gh.gh_wait); |
320dd101 | 671 | } |
b3b94faa DT |
672 | spin_unlock(&gl->gl_spin); |
673 | ||
674 | wait_for_completion(&gh.gh_wait); | |
675 | gfs2_holder_uninit(&gh); | |
676 | } | |
677 | ||
678 | /** | |
679 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock | |
680 | * @gl: the glock | |
681 | * | |
682 | * Returns: 1 if the glock is acquired | |
683 | */ | |
684 | ||
08bc2dbc | 685 | static int gfs2_glmutex_trylock(struct gfs2_glock *gl) |
b3b94faa DT |
686 | { |
687 | int acquired = 1; | |
688 | ||
689 | spin_lock(&gl->gl_spin); | |
690 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
691 | acquired = 0; | |
320dd101 SW |
692 | else { |
693 | gl->gl_owner = current; | |
694 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
695 | } | |
b3b94faa DT |
696 | spin_unlock(&gl->gl_spin); |
697 | ||
698 | return acquired; | |
699 | } | |
700 | ||
701 | /** | |
702 | * gfs2_glmutex_unlock - release a local lock on a glock | |
703 | * @gl: the glock | |
704 | * | |
705 | */ | |
706 | ||
feaa7bba | 707 | static void gfs2_glmutex_unlock(struct gfs2_glock *gl) |
b3b94faa DT |
708 | { |
709 | spin_lock(&gl->gl_spin); | |
710 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
320dd101 SW |
711 | gl->gl_owner = NULL; |
712 | gl->gl_ip = 0; | |
b3b94faa | 713 | run_queue(gl); |
190562bd | 714 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
715 | spin_unlock(&gl->gl_spin); |
716 | } | |
717 | ||
718 | /** | |
719 | * handle_callback - add a demote request to a lock's queue | |
720 | * @gl: the glock | |
721 | * @state: the state the caller wants us to change to | |
722 | * | |
723 | */ | |
724 | ||
725 | static void handle_callback(struct gfs2_glock *gl, unsigned int state) | |
726 | { | |
727 | struct gfs2_holder *gh, *new_gh = NULL; | |
728 | ||
feaa7bba | 729 | restart: |
b3b94faa DT |
730 | spin_lock(&gl->gl_spin); |
731 | ||
732 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
733 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && | |
734 | gl->gl_req_gh != gh) { | |
735 | if (gh->gh_state != state) | |
736 | gh->gh_state = LM_ST_UNLOCKED; | |
737 | goto out; | |
738 | } | |
739 | } | |
740 | ||
741 | if (new_gh) { | |
742 | list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); | |
743 | new_gh = NULL; | |
744 | } else { | |
745 | spin_unlock(&gl->gl_spin); | |
746 | ||
579b78a4 | 747 | new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, |
b3b94faa DT |
748 | GFP_KERNEL | __GFP_NOFAIL), |
749 | set_bit(HIF_DEMOTE, &new_gh->gh_iflags); | |
750 | set_bit(HIF_DEALLOC, &new_gh->gh_iflags); | |
751 | ||
752 | goto restart; | |
753 | } | |
754 | ||
feaa7bba | 755 | out: |
b3b94faa DT |
756 | spin_unlock(&gl->gl_spin); |
757 | ||
758 | if (new_gh) | |
759 | gfs2_holder_put(new_gh); | |
760 | } | |
761 | ||
feaa7bba SW |
762 | void gfs2_glock_inode_squish(struct inode *inode) |
763 | { | |
764 | struct gfs2_holder gh; | |
765 | struct gfs2_glock *gl = GFS2_I(inode)->i_gl; | |
766 | gfs2_holder_init(gl, LM_ST_UNLOCKED, 0, &gh); | |
767 | set_bit(HIF_DEMOTE, &gh.gh_iflags); | |
768 | spin_lock(&gl->gl_spin); | |
769 | gfs2_assert(inode->i_sb->s_fs_info, list_empty(&gl->gl_holders)); | |
770 | list_add_tail(&gh.gh_list, &gl->gl_waiters2); | |
771 | run_queue(gl); | |
772 | spin_unlock(&gl->gl_spin); | |
773 | gfs2_holder_uninit(&gh); | |
774 | } | |
775 | ||
b3b94faa DT |
776 | /** |
777 | * state_change - record that the glock is now in a different state | |
778 | * @gl: the glock | |
779 | * @new_state the new state | |
780 | * | |
781 | */ | |
782 | ||
783 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
784 | { | |
b3b94faa DT |
785 | int held1, held2; |
786 | ||
787 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
788 | held2 = (new_state != LM_ST_UNLOCKED); | |
789 | ||
790 | if (held1 != held2) { | |
6a6b3d01 | 791 | if (held2) |
b3b94faa | 792 | gfs2_glock_hold(gl); |
6a6b3d01 | 793 | else |
b3b94faa | 794 | gfs2_glock_put(gl); |
b3b94faa DT |
795 | } |
796 | ||
797 | gl->gl_state = new_state; | |
798 | } | |
799 | ||
800 | /** | |
801 | * xmote_bh - Called after the lock module is done acquiring a lock | |
802 | * @gl: The glock in question | |
803 | * @ret: the int returned from the lock module | |
804 | * | |
805 | */ | |
806 | ||
807 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) | |
808 | { | |
809 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
810 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
811 | struct gfs2_holder *gh = gl->gl_req_gh; | |
812 | int prev_state = gl->gl_state; | |
813 | int op_done = 1; | |
814 | ||
815 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
816 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
817 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); | |
818 | ||
819 | state_change(gl, ret & LM_OUT_ST_MASK); | |
820 | ||
821 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { | |
822 | if (glops->go_inval) | |
823 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
824 | } else if (gl->gl_state == LM_ST_DEFERRED) { | |
825 | /* We might not want to do this here. | |
826 | Look at moving to the inode glops. */ | |
827 | if (glops->go_inval) | |
828 | glops->go_inval(gl, DIO_DATA); | |
829 | } | |
830 | ||
831 | /* Deal with each possible exit condition */ | |
832 | ||
833 | if (!gh) | |
834 | gl->gl_stamp = jiffies; | |
835 | ||
836 | else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { | |
837 | spin_lock(&gl->gl_spin); | |
838 | list_del_init(&gh->gh_list); | |
839 | gh->gh_error = -EIO; | |
b3b94faa DT |
840 | spin_unlock(&gl->gl_spin); |
841 | ||
842 | } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { | |
843 | spin_lock(&gl->gl_spin); | |
844 | list_del_init(&gh->gh_list); | |
845 | if (gl->gl_state == gh->gh_state || | |
846 | gl->gl_state == LM_ST_UNLOCKED) | |
847 | gh->gh_error = 0; | |
848 | else { | |
849 | if (gfs2_assert_warn(sdp, gh->gh_flags & | |
850 | (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) | |
851 | fs_warn(sdp, "ret = 0x%.8X\n", ret); | |
852 | gh->gh_error = GLR_TRYFAILED; | |
853 | } | |
854 | spin_unlock(&gl->gl_spin); | |
855 | ||
856 | if (ret & LM_OUT_CANCELED) | |
857 | handle_callback(gl, LM_ST_UNLOCKED); /* Lame */ | |
858 | ||
859 | } else if (ret & LM_OUT_CANCELED) { | |
860 | spin_lock(&gl->gl_spin); | |
861 | list_del_init(&gh->gh_list); | |
862 | gh->gh_error = GLR_CANCELED; | |
b3b94faa DT |
863 | spin_unlock(&gl->gl_spin); |
864 | ||
865 | } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
866 | spin_lock(&gl->gl_spin); | |
867 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
868 | gh->gh_error = 0; | |
869 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
870 | spin_unlock(&gl->gl_spin); | |
871 | ||
872 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
873 | ||
874 | op_done = 0; | |
875 | ||
876 | } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
877 | spin_lock(&gl->gl_spin); | |
878 | list_del_init(&gh->gh_list); | |
879 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
880 | spin_unlock(&gl->gl_spin); |
881 | ||
882 | } else { | |
883 | if (gfs2_assert_withdraw(sdp, 0) == -1) | |
884 | fs_err(sdp, "ret = 0x%.8X\n", ret); | |
885 | } | |
886 | ||
887 | if (glops->go_xmote_bh) | |
888 | glops->go_xmote_bh(gl); | |
889 | ||
890 | if (op_done) { | |
891 | spin_lock(&gl->gl_spin); | |
892 | gl->gl_req_gh = NULL; | |
893 | gl->gl_req_bh = NULL; | |
894 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
895 | run_queue(gl); | |
896 | spin_unlock(&gl->gl_spin); | |
897 | } | |
898 | ||
899 | gfs2_glock_put(gl); | |
900 | ||
901 | if (gh) { | |
902 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
903 | gfs2_holder_put(gh); | |
904 | else | |
905 | complete(&gh->gh_wait); | |
906 | } | |
907 | } | |
908 | ||
909 | /** | |
910 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock | |
911 | * @gl: The glock in question | |
912 | * @state: the requested state | |
913 | * @flags: modifier flags to the lock call | |
914 | * | |
915 | */ | |
916 | ||
917 | void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags) | |
918 | { | |
919 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
920 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
921 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | | |
922 | LM_FLAG_NOEXP | LM_FLAG_ANY | | |
923 | LM_FLAG_PRIORITY); | |
924 | unsigned int lck_ret; | |
925 | ||
926 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
927 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
928 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); | |
929 | gfs2_assert_warn(sdp, state != gl->gl_state); | |
930 | ||
931 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
932 | if (glops->go_sync) | |
933 | glops->go_sync(gl, | |
934 | DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
935 | } | |
936 | ||
937 | gfs2_glock_hold(gl); | |
938 | gl->gl_req_bh = xmote_bh; | |
939 | ||
b3b94faa DT |
940 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, |
941 | lck_flags); | |
942 | ||
943 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) | |
944 | return; | |
945 | ||
946 | if (lck_ret & LM_OUT_ASYNC) | |
947 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); | |
948 | else | |
949 | xmote_bh(gl, lck_ret); | |
950 | } | |
951 | ||
952 | /** | |
953 | * drop_bh - Called after a lock module unlock completes | |
954 | * @gl: the glock | |
955 | * @ret: the return status | |
956 | * | |
957 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) | |
958 | * Doesn't drop the reference on the glock the top half took out | |
959 | * | |
960 | */ | |
961 | ||
962 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) | |
963 | { | |
964 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
965 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
966 | struct gfs2_holder *gh = gl->gl_req_gh; | |
967 | ||
968 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
969 | ||
970 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
971 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
972 | gfs2_assert_warn(sdp, !ret); | |
973 | ||
974 | state_change(gl, LM_ST_UNLOCKED); | |
975 | ||
976 | if (glops->go_inval) | |
977 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
978 | ||
979 | if (gh) { | |
980 | spin_lock(&gl->gl_spin); | |
981 | list_del_init(&gh->gh_list); | |
982 | gh->gh_error = 0; | |
983 | spin_unlock(&gl->gl_spin); | |
984 | } | |
985 | ||
986 | if (glops->go_drop_bh) | |
987 | glops->go_drop_bh(gl); | |
988 | ||
989 | spin_lock(&gl->gl_spin); | |
990 | gl->gl_req_gh = NULL; | |
991 | gl->gl_req_bh = NULL; | |
992 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
993 | run_queue(gl); | |
994 | spin_unlock(&gl->gl_spin); | |
995 | ||
996 | gfs2_glock_put(gl); | |
997 | ||
998 | if (gh) { | |
999 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
1000 | gfs2_holder_put(gh); | |
1001 | else | |
1002 | complete(&gh->gh_wait); | |
1003 | } | |
1004 | } | |
1005 | ||
1006 | /** | |
1007 | * gfs2_glock_drop_th - call into the lock module to unlock a lock | |
1008 | * @gl: the glock | |
1009 | * | |
1010 | */ | |
1011 | ||
1012 | void gfs2_glock_drop_th(struct gfs2_glock *gl) | |
1013 | { | |
1014 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1015 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1016 | unsigned int ret; | |
1017 | ||
1018 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1019 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
1020 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); | |
1021 | ||
1022 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
1023 | if (glops->go_sync) | |
1024 | glops->go_sync(gl, | |
1025 | DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
1026 | } | |
1027 | ||
1028 | gfs2_glock_hold(gl); | |
1029 | gl->gl_req_bh = drop_bh; | |
1030 | ||
b3b94faa DT |
1031 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
1032 | ||
1033 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) | |
1034 | return; | |
1035 | ||
1036 | if (!ret) | |
1037 | drop_bh(gl, ret); | |
1038 | else | |
1039 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); | |
1040 | } | |
1041 | ||
1042 | /** | |
1043 | * do_cancels - cancel requests for locks stuck waiting on an expire flag | |
1044 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock | |
1045 | * | |
1046 | * Don't cancel GL_NOCANCEL requests. | |
1047 | */ | |
1048 | ||
1049 | static void do_cancels(struct gfs2_holder *gh) | |
1050 | { | |
1051 | struct gfs2_glock *gl = gh->gh_gl; | |
1052 | ||
1053 | spin_lock(&gl->gl_spin); | |
1054 | ||
1055 | while (gl->gl_req_gh != gh && | |
1056 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1057 | !list_empty(&gh->gh_list)) { | |
1058 | if (gl->gl_req_bh && | |
1059 | !(gl->gl_req_gh && | |
1060 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { | |
1061 | spin_unlock(&gl->gl_spin); | |
1062 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); | |
1063 | msleep(100); | |
1064 | spin_lock(&gl->gl_spin); | |
1065 | } else { | |
1066 | spin_unlock(&gl->gl_spin); | |
1067 | msleep(100); | |
1068 | spin_lock(&gl->gl_spin); | |
1069 | } | |
1070 | } | |
1071 | ||
1072 | spin_unlock(&gl->gl_spin); | |
1073 | } | |
1074 | ||
1075 | /** | |
1076 | * glock_wait_internal - wait on a glock acquisition | |
1077 | * @gh: the glock holder | |
1078 | * | |
1079 | * Returns: 0 on success | |
1080 | */ | |
1081 | ||
1082 | static int glock_wait_internal(struct gfs2_holder *gh) | |
1083 | { | |
1084 | struct gfs2_glock *gl = gh->gh_gl; | |
1085 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1086 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1087 | ||
1088 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) | |
1089 | return -EIO; | |
1090 | ||
1091 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
1092 | spin_lock(&gl->gl_spin); | |
1093 | if (gl->gl_req_gh != gh && | |
1094 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1095 | !list_empty(&gh->gh_list)) { | |
1096 | list_del_init(&gh->gh_list); | |
1097 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
1098 | run_queue(gl); |
1099 | spin_unlock(&gl->gl_spin); | |
1100 | return gh->gh_error; | |
1101 | } | |
1102 | spin_unlock(&gl->gl_spin); | |
1103 | } | |
1104 | ||
1105 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1106 | do_cancels(gh); | |
1107 | ||
1108 | wait_for_completion(&gh->gh_wait); | |
1109 | ||
1110 | if (gh->gh_error) | |
1111 | return gh->gh_error; | |
1112 | ||
1113 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); | |
1114 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, | |
1115 | gh->gh_state, | |
1116 | gh->gh_flags)); | |
1117 | ||
1118 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { | |
1119 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1120 | ||
1121 | if (glops->go_lock) { | |
1122 | gh->gh_error = glops->go_lock(gh); | |
1123 | if (gh->gh_error) { | |
1124 | spin_lock(&gl->gl_spin); | |
1125 | list_del_init(&gh->gh_list); | |
b3b94faa DT |
1126 | spin_unlock(&gl->gl_spin); |
1127 | } | |
1128 | } | |
1129 | ||
1130 | spin_lock(&gl->gl_spin); | |
1131 | gl->gl_req_gh = NULL; | |
1132 | gl->gl_req_bh = NULL; | |
1133 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
1134 | run_queue(gl); |
1135 | spin_unlock(&gl->gl_spin); | |
1136 | } | |
1137 | ||
1138 | return gh->gh_error; | |
1139 | } | |
1140 | ||
1141 | static inline struct gfs2_holder * | |
1142 | find_holder_by_owner(struct list_head *head, struct task_struct *owner) | |
1143 | { | |
1144 | struct gfs2_holder *gh; | |
1145 | ||
1146 | list_for_each_entry(gh, head, gh_list) { | |
1147 | if (gh->gh_owner == owner) | |
1148 | return gh; | |
1149 | } | |
1150 | ||
1151 | return NULL; | |
1152 | } | |
1153 | ||
b3b94faa DT |
1154 | /** |
1155 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
1156 | * @gh: the holder structure to add | |
1157 | * | |
1158 | */ | |
1159 | ||
1160 | static void add_to_queue(struct gfs2_holder *gh) | |
1161 | { | |
1162 | struct gfs2_glock *gl = gh->gh_gl; | |
1163 | struct gfs2_holder *existing; | |
1164 | ||
190562bd SW |
1165 | BUG_ON(!gh->gh_owner); |
1166 | ||
b3b94faa DT |
1167 | existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner); |
1168 | if (existing) { | |
5965b1f4 SW |
1169 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
1170 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); | |
1171 | BUG(); | |
b3b94faa DT |
1172 | } |
1173 | ||
1174 | existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner); | |
1175 | if (existing) { | |
5965b1f4 SW |
1176 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
1177 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); | |
1178 | BUG(); | |
b3b94faa DT |
1179 | } |
1180 | ||
b3b94faa DT |
1181 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
1182 | list_add(&gh->gh_list, &gl->gl_waiters3); | |
1183 | else | |
1184 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); | |
1185 | } | |
1186 | ||
1187 | /** | |
1188 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1189 | * @gh: the holder structure | |
1190 | * | |
1191 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1192 | * | |
1193 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1194 | */ | |
1195 | ||
1196 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1197 | { | |
1198 | struct gfs2_glock *gl = gh->gh_gl; | |
1199 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1200 | int error = 0; | |
1201 | ||
320dd101 | 1202 | restart: |
b3b94faa DT |
1203 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
1204 | set_bit(HIF_ABORTED, &gh->gh_iflags); | |
1205 | return -EIO; | |
1206 | } | |
1207 | ||
1208 | set_bit(HIF_PROMOTE, &gh->gh_iflags); | |
1209 | ||
1210 | spin_lock(&gl->gl_spin); | |
1211 | add_to_queue(gh); | |
1212 | run_queue(gl); | |
1213 | spin_unlock(&gl->gl_spin); | |
1214 | ||
1215 | if (!(gh->gh_flags & GL_ASYNC)) { | |
1216 | error = glock_wait_internal(gh); | |
1217 | if (error == GLR_CANCELED) { | |
190562bd | 1218 | msleep(100); |
b3b94faa DT |
1219 | goto restart; |
1220 | } | |
1221 | } | |
1222 | ||
1223 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
1224 | ||
320dd101 SW |
1225 | if (error == GLR_TRYFAILED && (gh->gh_flags & GL_DUMP)) |
1226 | dump_glock(gl); | |
1227 | ||
b3b94faa DT |
1228 | return error; |
1229 | } | |
1230 | ||
1231 | /** | |
1232 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1233 | * @gh: the holder | |
1234 | * | |
1235 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1236 | */ | |
1237 | ||
1238 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1239 | { | |
1240 | struct gfs2_glock *gl = gh->gh_gl; | |
1241 | int ready = 0; | |
1242 | ||
1243 | spin_lock(&gl->gl_spin); | |
1244 | ||
1245 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1246 | ready = 1; | |
1247 | else if (list_empty(&gh->gh_list)) { | |
1248 | if (gh->gh_error == GLR_CANCELED) { | |
1249 | spin_unlock(&gl->gl_spin); | |
190562bd | 1250 | msleep(100); |
b3b94faa DT |
1251 | if (gfs2_glock_nq(gh)) |
1252 | return 1; | |
1253 | return 0; | |
1254 | } else | |
1255 | ready = 1; | |
1256 | } | |
1257 | ||
1258 | spin_unlock(&gl->gl_spin); | |
1259 | ||
1260 | return ready; | |
1261 | } | |
1262 | ||
1263 | /** | |
1264 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC | |
1265 | * @gh: the holder structure | |
1266 | * | |
1267 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1268 | */ | |
1269 | ||
1270 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
1271 | { | |
1272 | int error; | |
1273 | ||
1274 | error = glock_wait_internal(gh); | |
1275 | if (error == GLR_CANCELED) { | |
190562bd | 1276 | msleep(100); |
b3b94faa DT |
1277 | gh->gh_flags &= ~GL_ASYNC; |
1278 | error = gfs2_glock_nq(gh); | |
1279 | } | |
1280 | ||
1281 | return error; | |
1282 | } | |
1283 | ||
1284 | /** | |
1285 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1286 | * @gh: the glock holder | |
1287 | * | |
1288 | */ | |
1289 | ||
1290 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1291 | { | |
1292 | struct gfs2_glock *gl = gh->gh_gl; | |
b3b94faa DT |
1293 | struct gfs2_glock_operations *glops = gl->gl_ops; |
1294 | ||
b3b94faa DT |
1295 | if (gh->gh_flags & GL_SYNC) |
1296 | set_bit(GLF_SYNC, &gl->gl_flags); | |
1297 | ||
1298 | if (gh->gh_flags & GL_NOCACHE) | |
1299 | handle_callback(gl, LM_ST_UNLOCKED); | |
1300 | ||
1301 | gfs2_glmutex_lock(gl); | |
1302 | ||
1303 | spin_lock(&gl->gl_spin); | |
1304 | list_del_init(&gh->gh_list); | |
1305 | ||
1306 | if (list_empty(&gl->gl_holders)) { | |
1307 | spin_unlock(&gl->gl_spin); | |
1308 | ||
1309 | if (glops->go_unlock) | |
1310 | glops->go_unlock(gh); | |
1311 | ||
1312 | if (test_bit(GLF_SYNC, &gl->gl_flags)) { | |
1313 | if (glops->go_sync) | |
1314 | glops->go_sync(gl, DIO_METADATA | DIO_DATA); | |
1315 | } | |
1316 | ||
1317 | gl->gl_stamp = jiffies; | |
1318 | ||
1319 | spin_lock(&gl->gl_spin); | |
1320 | } | |
1321 | ||
1322 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1323 | run_queue(gl); | |
1324 | spin_unlock(&gl->gl_spin); | |
1325 | } | |
1326 | ||
1327 | /** | |
1328 | * gfs2_glock_prefetch - Try to prefetch a glock | |
1329 | * @gl: the glock | |
1330 | * @state: the state to prefetch in | |
1331 | * @flags: flags passed to go_xmote_th() | |
1332 | * | |
1333 | */ | |
1334 | ||
08bc2dbc AB |
1335 | static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state, |
1336 | int flags) | |
b3b94faa DT |
1337 | { |
1338 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1339 | ||
1340 | spin_lock(&gl->gl_spin); | |
1341 | ||
1342 | if (test_bit(GLF_LOCK, &gl->gl_flags) || | |
1343 | !list_empty(&gl->gl_holders) || | |
1344 | !list_empty(&gl->gl_waiters1) || | |
1345 | !list_empty(&gl->gl_waiters2) || | |
1346 | !list_empty(&gl->gl_waiters3) || | |
1347 | relaxed_state_ok(gl->gl_state, state, flags)) { | |
1348 | spin_unlock(&gl->gl_spin); | |
1349 | return; | |
1350 | } | |
1351 | ||
1352 | set_bit(GLF_PREFETCH, &gl->gl_flags); | |
1353 | set_bit(GLF_LOCK, &gl->gl_flags); | |
1354 | spin_unlock(&gl->gl_spin); | |
1355 | ||
1356 | glops->go_xmote_th(gl, state, flags); | |
b3b94faa DT |
1357 | } |
1358 | ||
b3b94faa DT |
1359 | static void greedy_work(void *data) |
1360 | { | |
e7f5c01c | 1361 | struct greedy *gr = data; |
b3b94faa DT |
1362 | struct gfs2_holder *gh = &gr->gr_gh; |
1363 | struct gfs2_glock *gl = gh->gh_gl; | |
1364 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1365 | ||
1366 | clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1367 | ||
1368 | if (glops->go_greedy) | |
1369 | glops->go_greedy(gl); | |
1370 | ||
1371 | spin_lock(&gl->gl_spin); | |
1372 | ||
1373 | if (list_empty(&gl->gl_waiters2)) { | |
1374 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1375 | spin_unlock(&gl->gl_spin); | |
1376 | gfs2_holder_uninit(gh); | |
1377 | kfree(gr); | |
1378 | } else { | |
1379 | gfs2_glock_hold(gl); | |
1380 | list_add_tail(&gh->gh_list, &gl->gl_waiters2); | |
1381 | run_queue(gl); | |
1382 | spin_unlock(&gl->gl_spin); | |
1383 | gfs2_glock_put(gl); | |
1384 | } | |
1385 | } | |
1386 | ||
1387 | /** | |
1388 | * gfs2_glock_be_greedy - | |
1389 | * @gl: | |
1390 | * @time: | |
1391 | * | |
1392 | * Returns: 0 if go_greedy will be called, 1 otherwise | |
1393 | */ | |
1394 | ||
1395 | int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time) | |
1396 | { | |
1397 | struct greedy *gr; | |
1398 | struct gfs2_holder *gh; | |
1399 | ||
feaa7bba | 1400 | if (!time || gl->gl_sbd->sd_args.ar_localcaching || |
b3b94faa DT |
1401 | test_and_set_bit(GLF_GREEDY, &gl->gl_flags)) |
1402 | return 1; | |
1403 | ||
1404 | gr = kmalloc(sizeof(struct greedy), GFP_KERNEL); | |
1405 | if (!gr) { | |
1406 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1407 | return 1; | |
1408 | } | |
1409 | gh = &gr->gr_gh; | |
1410 | ||
579b78a4 | 1411 | gfs2_holder_init(gl, 0, 0, gh); |
b3b94faa DT |
1412 | set_bit(HIF_GREEDY, &gh->gh_iflags); |
1413 | INIT_WORK(&gr->gr_work, greedy_work, gr); | |
1414 | ||
1415 | set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1416 | schedule_delayed_work(&gr->gr_work, time); | |
1417 | ||
1418 | return 0; | |
1419 | } | |
1420 | ||
b3b94faa DT |
1421 | /** |
1422 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1423 | * @gh: the holder structure | |
1424 | * | |
1425 | */ | |
1426 | ||
1427 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1428 | { | |
1429 | gfs2_glock_dq(gh); | |
1430 | gfs2_holder_uninit(gh); | |
1431 | } | |
1432 | ||
1433 | /** | |
1434 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1435 | * @sdp: the filesystem | |
1436 | * @number: the lock number | |
1437 | * @glops: the glock operations for the type of glock | |
1438 | * @state: the state to acquire the glock in | |
1439 | * @flags: modifier flags for the aquisition | |
1440 | * @gh: the struct gfs2_holder | |
1441 | * | |
1442 | * Returns: errno | |
1443 | */ | |
1444 | ||
1445 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, uint64_t number, | |
1446 | struct gfs2_glock_operations *glops, unsigned int state, | |
1447 | int flags, struct gfs2_holder *gh) | |
1448 | { | |
1449 | struct gfs2_glock *gl; | |
1450 | int error; | |
1451 | ||
1452 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1453 | if (!error) { | |
1454 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1455 | gfs2_glock_put(gl); | |
1456 | } | |
1457 | ||
1458 | return error; | |
1459 | } | |
1460 | ||
1461 | /** | |
1462 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1463 | * @arg_a: the first structure | |
1464 | * @arg_b: the second structure | |
1465 | * | |
1466 | */ | |
1467 | ||
1468 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1469 | { | |
1470 | struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a; | |
1471 | struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b; | |
1472 | struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1473 | struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
1474 | int ret = 0; | |
1475 | ||
1476 | if (a->ln_number > b->ln_number) | |
1477 | ret = 1; | |
1478 | else if (a->ln_number < b->ln_number) | |
1479 | ret = -1; | |
1480 | else { | |
1481 | if (gh_a->gh_state == LM_ST_SHARED && | |
1482 | gh_b->gh_state == LM_ST_EXCLUSIVE) | |
1483 | ret = 1; | |
1484 | else if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && | |
1485 | (gh_b->gh_flags & GL_LOCAL_EXCL)) | |
1486 | ret = 1; | |
1487 | } | |
1488 | ||
1489 | return ret; | |
1490 | } | |
1491 | ||
1492 | /** | |
1493 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1494 | * @num_gh: the number of structures | |
1495 | * @ghs: an array of struct gfs2_holder structures | |
1496 | * | |
1497 | * Returns: 0 on success (all glocks acquired), | |
1498 | * errno on failure (no glocks acquired) | |
1499 | */ | |
1500 | ||
1501 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1502 | struct gfs2_holder **p) | |
1503 | { | |
1504 | unsigned int x; | |
1505 | int error = 0; | |
1506 | ||
1507 | for (x = 0; x < num_gh; x++) | |
1508 | p[x] = &ghs[x]; | |
1509 | ||
1510 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1511 | ||
1512 | for (x = 0; x < num_gh; x++) { | |
1513 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1514 | ||
1515 | error = gfs2_glock_nq(p[x]); | |
1516 | if (error) { | |
1517 | while (x--) | |
1518 | gfs2_glock_dq(p[x]); | |
1519 | break; | |
1520 | } | |
1521 | } | |
1522 | ||
1523 | return error; | |
1524 | } | |
1525 | ||
1526 | /** | |
1527 | * gfs2_glock_nq_m - acquire multiple glocks | |
1528 | * @num_gh: the number of structures | |
1529 | * @ghs: an array of struct gfs2_holder structures | |
1530 | * | |
1531 | * Figure out how big an impact this function has. Either: | |
1532 | * 1) Replace this code with code that calls gfs2_glock_prefetch() | |
1533 | * 2) Forget async stuff and just call nq_m_sync() | |
1534 | * 3) Leave it like it is | |
1535 | * | |
1536 | * Returns: 0 on success (all glocks acquired), | |
1537 | * errno on failure (no glocks acquired) | |
1538 | */ | |
1539 | ||
1540 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1541 | { | |
1542 | int *e; | |
1543 | unsigned int x; | |
1544 | int borked = 0, serious = 0; | |
1545 | int error = 0; | |
1546 | ||
1547 | if (!num_gh) | |
1548 | return 0; | |
1549 | ||
1550 | if (num_gh == 1) { | |
1551 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1552 | return gfs2_glock_nq(ghs); | |
1553 | } | |
1554 | ||
1555 | e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL); | |
1556 | if (!e) | |
1557 | return -ENOMEM; | |
1558 | ||
1559 | for (x = 0; x < num_gh; x++) { | |
1560 | ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC; | |
1561 | error = gfs2_glock_nq(&ghs[x]); | |
1562 | if (error) { | |
1563 | borked = 1; | |
1564 | serious = error; | |
1565 | num_gh = x; | |
1566 | break; | |
1567 | } | |
1568 | } | |
1569 | ||
1570 | for (x = 0; x < num_gh; x++) { | |
1571 | error = e[x] = glock_wait_internal(&ghs[x]); | |
1572 | if (error) { | |
1573 | borked = 1; | |
1574 | if (error != GLR_TRYFAILED && error != GLR_CANCELED) | |
1575 | serious = error; | |
1576 | } | |
1577 | } | |
1578 | ||
1579 | if (!borked) { | |
1580 | kfree(e); | |
1581 | return 0; | |
1582 | } | |
1583 | ||
1584 | for (x = 0; x < num_gh; x++) | |
1585 | if (!e[x]) | |
1586 | gfs2_glock_dq(&ghs[x]); | |
1587 | ||
1588 | if (serious) | |
1589 | error = serious; | |
1590 | else { | |
1591 | for (x = 0; x < num_gh; x++) | |
1592 | gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags, | |
1593 | &ghs[x]); | |
1594 | error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e); | |
1595 | } | |
1596 | ||
1597 | kfree(e); | |
1598 | ||
1599 | return error; | |
1600 | } | |
1601 | ||
1602 | /** | |
1603 | * gfs2_glock_dq_m - release multiple glocks | |
1604 | * @num_gh: the number of structures | |
1605 | * @ghs: an array of struct gfs2_holder structures | |
1606 | * | |
1607 | */ | |
1608 | ||
1609 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1610 | { | |
1611 | unsigned int x; | |
1612 | ||
1613 | for (x = 0; x < num_gh; x++) | |
1614 | gfs2_glock_dq(&ghs[x]); | |
1615 | } | |
1616 | ||
1617 | /** | |
1618 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1619 | * @num_gh: the number of structures | |
1620 | * @ghs: an array of struct gfs2_holder structures | |
1621 | * | |
1622 | */ | |
1623 | ||
1624 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1625 | { | |
1626 | unsigned int x; | |
1627 | ||
1628 | for (x = 0; x < num_gh; x++) | |
1629 | gfs2_glock_dq_uninit(&ghs[x]); | |
1630 | } | |
1631 | ||
1632 | /** | |
1633 | * gfs2_glock_prefetch_num - prefetch a glock based on lock number | |
1634 | * @sdp: the filesystem | |
1635 | * @number: the lock number | |
1636 | * @glops: the glock operations for the type of glock | |
1637 | * @state: the state to acquire the glock in | |
1638 | * @flags: modifier flags for the aquisition | |
1639 | * | |
1640 | * Returns: errno | |
1641 | */ | |
1642 | ||
1643 | void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, uint64_t number, | |
1644 | struct gfs2_glock_operations *glops, | |
1645 | unsigned int state, int flags) | |
1646 | { | |
1647 | struct gfs2_glock *gl; | |
1648 | int error; | |
1649 | ||
1650 | if (atomic_read(&sdp->sd_reclaim_count) < | |
1651 | gfs2_tune_get(sdp, gt_reclaim_limit)) { | |
1652 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1653 | if (!error) { | |
1654 | gfs2_glock_prefetch(gl, state, flags); | |
1655 | gfs2_glock_put(gl); | |
1656 | } | |
1657 | } | |
1658 | } | |
1659 | ||
1660 | /** | |
1661 | * gfs2_lvb_hold - attach a LVB from a glock | |
1662 | * @gl: The glock in question | |
1663 | * | |
1664 | */ | |
1665 | ||
1666 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1667 | { | |
1668 | int error; | |
1669 | ||
1670 | gfs2_glmutex_lock(gl); | |
1671 | ||
1672 | if (!atomic_read(&gl->gl_lvb_count)) { | |
1673 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
1674 | if (error) { | |
1675 | gfs2_glmutex_unlock(gl); | |
1676 | return error; | |
1677 | } | |
1678 | gfs2_glock_hold(gl); | |
1679 | } | |
1680 | atomic_inc(&gl->gl_lvb_count); | |
1681 | ||
1682 | gfs2_glmutex_unlock(gl); | |
1683 | ||
1684 | return 0; | |
1685 | } | |
1686 | ||
1687 | /** | |
1688 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1689 | * @gl: The glock in question | |
1690 | * | |
1691 | */ | |
1692 | ||
1693 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1694 | { | |
1695 | gfs2_glock_hold(gl); | |
1696 | gfs2_glmutex_lock(gl); | |
1697 | ||
1698 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); | |
1699 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
1700 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1701 | gl->gl_lvb = NULL; | |
1702 | gfs2_glock_put(gl); | |
1703 | } | |
1704 | ||
1705 | gfs2_glmutex_unlock(gl); | |
1706 | gfs2_glock_put(gl); | |
1707 | } | |
1708 | ||
08bc2dbc | 1709 | #if 0 |
b3b94faa DT |
1710 | void gfs2_lvb_sync(struct gfs2_glock *gl) |
1711 | { | |
1712 | gfs2_glmutex_lock(gl); | |
1713 | ||
1714 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count)); | |
1715 | if (!gfs2_assert_warn(gl->gl_sbd, gfs2_glock_is_held_excl(gl))) | |
1716 | gfs2_lm_sync_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1717 | ||
1718 | gfs2_glmutex_unlock(gl); | |
1719 | } | |
08bc2dbc | 1720 | #endif /* 0 */ |
b3b94faa DT |
1721 | |
1722 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, | |
1723 | unsigned int state) | |
1724 | { | |
1725 | struct gfs2_glock *gl; | |
1726 | ||
1727 | gl = gfs2_glock_find(sdp, name); | |
1728 | if (!gl) | |
1729 | return; | |
1730 | ||
1731 | if (gl->gl_ops->go_callback) | |
1732 | gl->gl_ops->go_callback(gl, state); | |
1733 | handle_callback(gl, state); | |
1734 | ||
1735 | spin_lock(&gl->gl_spin); | |
1736 | run_queue(gl); | |
1737 | spin_unlock(&gl->gl_spin); | |
1738 | ||
1739 | gfs2_glock_put(gl); | |
1740 | } | |
1741 | ||
1742 | /** | |
1743 | * gfs2_glock_cb - Callback used by locking module | |
1744 | * @fsdata: Pointer to the superblock | |
1745 | * @type: Type of callback | |
1746 | * @data: Type dependent data pointer | |
1747 | * | |
1748 | * Called by the locking module when it wants to tell us something. | |
1749 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1750 | * a journal from another client needs to be recovered. | |
1751 | */ | |
1752 | ||
1753 | void gfs2_glock_cb(lm_fsdata_t *fsdata, unsigned int type, void *data) | |
1754 | { | |
1755 | struct gfs2_sbd *sdp = (struct gfs2_sbd *)fsdata; | |
1756 | ||
b3b94faa DT |
1757 | switch (type) { |
1758 | case LM_CB_NEED_E: | |
e7f5c01c | 1759 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
b3b94faa DT |
1760 | return; |
1761 | ||
1762 | case LM_CB_NEED_D: | |
e7f5c01c | 1763 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
b3b94faa DT |
1764 | return; |
1765 | ||
1766 | case LM_CB_NEED_S: | |
e7f5c01c | 1767 | blocking_cb(sdp, data, LM_ST_SHARED); |
b3b94faa DT |
1768 | return; |
1769 | ||
1770 | case LM_CB_ASYNC: { | |
e7f5c01c | 1771 | struct lm_async_cb *async = data; |
b3b94faa DT |
1772 | struct gfs2_glock *gl; |
1773 | ||
1774 | gl = gfs2_glock_find(sdp, &async->lc_name); | |
1775 | if (gfs2_assert_warn(sdp, gl)) | |
1776 | return; | |
1777 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) | |
1778 | gl->gl_req_bh(gl, async->lc_ret); | |
1779 | gfs2_glock_put(gl); | |
b3b94faa DT |
1780 | return; |
1781 | } | |
1782 | ||
1783 | case LM_CB_NEED_RECOVERY: | |
1784 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1785 | if (sdp->sd_recoverd_process) | |
1786 | wake_up_process(sdp->sd_recoverd_process); | |
1787 | return; | |
1788 | ||
1789 | case LM_CB_DROPLOCKS: | |
1790 | gfs2_gl_hash_clear(sdp, NO_WAIT); | |
1791 | gfs2_quota_scan(sdp); | |
1792 | return; | |
1793 | ||
1794 | default: | |
1795 | gfs2_assert_warn(sdp, 0); | |
1796 | return; | |
1797 | } | |
1798 | } | |
1799 | ||
b3b94faa DT |
1800 | /** |
1801 | * gfs2_iopen_go_callback - Try to kick the inode/vnode associated with an | |
1802 | * iopen glock from memory | |
1803 | * @io_gl: the iopen glock | |
1804 | * @state: the state into which the glock should be put | |
1805 | * | |
1806 | */ | |
1807 | ||
1808 | void gfs2_iopen_go_callback(struct gfs2_glock *io_gl, unsigned int state) | |
1809 | { | |
b3b94faa DT |
1810 | |
1811 | if (state != LM_ST_UNLOCKED) | |
1812 | return; | |
feaa7bba | 1813 | /* FIXME: remove this? */ |
b3b94faa DT |
1814 | } |
1815 | ||
1816 | /** | |
1817 | * demote_ok - Check to see if it's ok to unlock a glock | |
1818 | * @gl: the glock | |
1819 | * | |
1820 | * Returns: 1 if it's ok | |
1821 | */ | |
1822 | ||
1823 | static int demote_ok(struct gfs2_glock *gl) | |
1824 | { | |
1825 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1826 | struct gfs2_glock_operations *glops = gl->gl_ops; | |
1827 | int demote = 1; | |
1828 | ||
1829 | if (test_bit(GLF_STICKY, &gl->gl_flags)) | |
1830 | demote = 0; | |
1831 | else if (test_bit(GLF_PREFETCH, &gl->gl_flags)) | |
1832 | demote = time_after_eq(jiffies, | |
1833 | gl->gl_stamp + | |
1834 | gfs2_tune_get(sdp, gt_prefetch_secs) * HZ); | |
1835 | else if (glops->go_demote_ok) | |
1836 | demote = glops->go_demote_ok(gl); | |
1837 | ||
1838 | return demote; | |
1839 | } | |
1840 | ||
1841 | /** | |
1842 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
1843 | * @gl: the glock | |
1844 | * | |
1845 | */ | |
1846 | ||
1847 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
1848 | { | |
1849 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1850 | ||
1851 | spin_lock(&sdp->sd_reclaim_lock); | |
1852 | if (list_empty(&gl->gl_reclaim)) { | |
1853 | gfs2_glock_hold(gl); | |
1854 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); | |
1855 | atomic_inc(&sdp->sd_reclaim_count); | |
1856 | } | |
1857 | spin_unlock(&sdp->sd_reclaim_lock); | |
1858 | ||
1859 | wake_up(&sdp->sd_reclaim_wq); | |
1860 | } | |
1861 | ||
1862 | /** | |
1863 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list | |
1864 | * @sdp: the filesystem | |
1865 | * | |
1866 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a | |
1867 | * different glock and we notice that there are a lot of glocks in the | |
1868 | * reclaim list. | |
1869 | * | |
1870 | */ | |
1871 | ||
1872 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) | |
1873 | { | |
1874 | struct gfs2_glock *gl; | |
1875 | ||
1876 | spin_lock(&sdp->sd_reclaim_lock); | |
1877 | if (list_empty(&sdp->sd_reclaim_list)) { | |
1878 | spin_unlock(&sdp->sd_reclaim_lock); | |
1879 | return; | |
1880 | } | |
1881 | gl = list_entry(sdp->sd_reclaim_list.next, | |
1882 | struct gfs2_glock, gl_reclaim); | |
1883 | list_del_init(&gl->gl_reclaim); | |
1884 | spin_unlock(&sdp->sd_reclaim_lock); | |
1885 | ||
1886 | atomic_dec(&sdp->sd_reclaim_count); | |
1887 | atomic_inc(&sdp->sd_reclaimed); | |
1888 | ||
1889 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa DT |
1890 | if (queue_empty(gl, &gl->gl_holders) && |
1891 | gl->gl_state != LM_ST_UNLOCKED && | |
1892 | demote_ok(gl)) | |
1893 | handle_callback(gl, LM_ST_UNLOCKED); | |
1894 | gfs2_glmutex_unlock(gl); | |
1895 | } | |
1896 | ||
1897 | gfs2_glock_put(gl); | |
1898 | } | |
1899 | ||
1900 | /** | |
1901 | * examine_bucket - Call a function for glock in a hash bucket | |
1902 | * @examiner: the function | |
1903 | * @sdp: the filesystem | |
1904 | * @bucket: the bucket | |
1905 | * | |
1906 | * Returns: 1 if the bucket has entries | |
1907 | */ | |
1908 | ||
1909 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
1910 | struct gfs2_gl_hash_bucket *bucket) | |
1911 | { | |
1912 | struct glock_plug plug; | |
1913 | struct list_head *tmp; | |
1914 | struct gfs2_glock *gl; | |
1915 | int entries; | |
1916 | ||
1917 | /* Add "plug" to end of bucket list, work back up list from there */ | |
1918 | memset(&plug.gl_flags, 0, sizeof(unsigned long)); | |
1919 | set_bit(GLF_PLUG, &plug.gl_flags); | |
1920 | ||
1921 | write_lock(&bucket->hb_lock); | |
1922 | list_add(&plug.gl_list, &bucket->hb_list); | |
1923 | write_unlock(&bucket->hb_lock); | |
1924 | ||
1925 | for (;;) { | |
1926 | write_lock(&bucket->hb_lock); | |
1927 | ||
1928 | for (;;) { | |
1929 | tmp = plug.gl_list.next; | |
1930 | ||
1931 | if (tmp == &bucket->hb_list) { | |
1932 | list_del(&plug.gl_list); | |
1933 | entries = !list_empty(&bucket->hb_list); | |
1934 | write_unlock(&bucket->hb_lock); | |
1935 | return entries; | |
1936 | } | |
1937 | gl = list_entry(tmp, struct gfs2_glock, gl_list); | |
1938 | ||
1939 | /* Move plug up list */ | |
1940 | list_move(&plug.gl_list, &gl->gl_list); | |
1941 | ||
1942 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
1943 | continue; | |
1944 | ||
1945 | /* examiner() must glock_put() */ | |
1946 | gfs2_glock_hold(gl); | |
1947 | ||
1948 | break; | |
1949 | } | |
1950 | ||
1951 | write_unlock(&bucket->hb_lock); | |
1952 | ||
1953 | examiner(gl); | |
1954 | } | |
1955 | } | |
1956 | ||
1957 | /** | |
1958 | * scan_glock - look at a glock and see if we can reclaim it | |
1959 | * @gl: the glock to look at | |
1960 | * | |
1961 | */ | |
1962 | ||
1963 | static void scan_glock(struct gfs2_glock *gl) | |
1964 | { | |
1965 | if (gfs2_glmutex_trylock(gl)) { | |
1966 | if (gl->gl_ops == &gfs2_inode_glops) { | |
5c676f6d | 1967 | struct gfs2_inode *ip = gl->gl_object; |
feaa7bba | 1968 | if (ip) |
b3b94faa DT |
1969 | goto out_schedule; |
1970 | } | |
1971 | if (queue_empty(gl, &gl->gl_holders) && | |
1972 | gl->gl_state != LM_ST_UNLOCKED && | |
1973 | demote_ok(gl)) | |
1974 | goto out_schedule; | |
1975 | ||
1976 | gfs2_glmutex_unlock(gl); | |
1977 | } | |
1978 | ||
1979 | gfs2_glock_put(gl); | |
1980 | ||
1981 | return; | |
1982 | ||
1983 | out_schedule: | |
1984 | gfs2_glmutex_unlock(gl); | |
1985 | gfs2_glock_schedule_for_reclaim(gl); | |
1986 | gfs2_glock_put(gl); | |
1987 | } | |
1988 | ||
1989 | /** | |
1990 | * gfs2_scand_internal - Look for glocks and inodes to toss from memory | |
1991 | * @sdp: the filesystem | |
1992 | * | |
1993 | */ | |
1994 | ||
1995 | void gfs2_scand_internal(struct gfs2_sbd *sdp) | |
1996 | { | |
1997 | unsigned int x; | |
1998 | ||
1999 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2000 | examine_bucket(scan_glock, sdp, &sdp->sd_gl_hash[x]); | |
2001 | cond_resched(); | |
2002 | } | |
2003 | } | |
2004 | ||
2005 | /** | |
2006 | * clear_glock - look at a glock and see if we can free it from glock cache | |
2007 | * @gl: the glock to look at | |
2008 | * | |
2009 | */ | |
2010 | ||
2011 | static void clear_glock(struct gfs2_glock *gl) | |
2012 | { | |
2013 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
2014 | int released; | |
2015 | ||
2016 | spin_lock(&sdp->sd_reclaim_lock); | |
2017 | if (!list_empty(&gl->gl_reclaim)) { | |
2018 | list_del_init(&gl->gl_reclaim); | |
2019 | atomic_dec(&sdp->sd_reclaim_count); | |
190562bd | 2020 | spin_unlock(&sdp->sd_reclaim_lock); |
b3b94faa DT |
2021 | released = gfs2_glock_put(gl); |
2022 | gfs2_assert(sdp, !released); | |
190562bd SW |
2023 | } else { |
2024 | spin_unlock(&sdp->sd_reclaim_lock); | |
b3b94faa | 2025 | } |
b3b94faa DT |
2026 | |
2027 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa DT |
2028 | if (queue_empty(gl, &gl->gl_holders) && |
2029 | gl->gl_state != LM_ST_UNLOCKED) | |
2030 | handle_callback(gl, LM_ST_UNLOCKED); | |
2031 | ||
2032 | gfs2_glmutex_unlock(gl); | |
2033 | } | |
2034 | ||
2035 | gfs2_glock_put(gl); | |
2036 | } | |
2037 | ||
2038 | /** | |
2039 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
2040 | * @sdp: the filesystem | |
2041 | * @wait: wait until it's all gone | |
2042 | * | |
2043 | * Called when unmounting the filesystem, or when inter-node lock manager | |
2044 | * requests DROPLOCKS because it is running out of capacity. | |
2045 | */ | |
2046 | ||
2047 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) | |
2048 | { | |
2049 | unsigned long t; | |
2050 | unsigned int x; | |
2051 | int cont; | |
2052 | ||
2053 | t = jiffies; | |
2054 | ||
2055 | for (;;) { | |
2056 | cont = 0; | |
2057 | ||
2058 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
2059 | if (examine_bucket(clear_glock, sdp, | |
2060 | &sdp->sd_gl_hash[x])) | |
2061 | cont = 1; | |
2062 | ||
2063 | if (!wait || !cont) | |
2064 | break; | |
2065 | ||
2066 | if (time_after_eq(jiffies, | |
2067 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
2068 | fs_warn(sdp, "Unmount seems to be stalled. " | |
2069 | "Dumping lock state...\n"); | |
2070 | gfs2_dump_lockstate(sdp); | |
2071 | t = jiffies; | |
2072 | } | |
2073 | ||
2074 | /* invalidate_inodes() requires that the sb inodes list | |
2075 | not change, but an async completion callback for an | |
2076 | unlock can occur which does glock_put() which | |
2077 | can call iput() which will change the sb inodes list. | |
2078 | invalidate_inodes_mutex prevents glock_put()'s during | |
2079 | an invalidate_inodes() */ | |
2080 | ||
f55ab26a | 2081 | mutex_lock(&sdp->sd_invalidate_inodes_mutex); |
b3b94faa | 2082 | invalidate_inodes(sdp->sd_vfs); |
f55ab26a | 2083 | mutex_unlock(&sdp->sd_invalidate_inodes_mutex); |
fd88de56 | 2084 | msleep(10); |
b3b94faa DT |
2085 | } |
2086 | } | |
2087 | ||
2088 | /* | |
2089 | * Diagnostic routines to help debug distributed deadlock | |
2090 | */ | |
2091 | ||
2092 | /** | |
2093 | * dump_holder - print information about a glock holder | |
2094 | * @str: a string naming the type of holder | |
2095 | * @gh: the glock holder | |
2096 | * | |
2097 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2098 | */ | |
2099 | ||
2100 | static int dump_holder(char *str, struct gfs2_holder *gh) | |
2101 | { | |
2102 | unsigned int x; | |
2103 | int error = -ENOBUFS; | |
2104 | ||
d92a8d48 SW |
2105 | printk(KERN_INFO " %s\n", str); |
2106 | printk(KERN_INFO " owner = %ld\n", | |
b3b94faa | 2107 | (gh->gh_owner) ? (long)gh->gh_owner->pid : -1); |
d92a8d48 SW |
2108 | printk(KERN_INFO " gh_state = %u\n", gh->gh_state); |
2109 | printk(KERN_INFO " gh_flags ="); | |
b3b94faa DT |
2110 | for (x = 0; x < 32; x++) |
2111 | if (gh->gh_flags & (1 << x)) | |
2112 | printk(" %u", x); | |
2113 | printk(" \n"); | |
d92a8d48 SW |
2114 | printk(KERN_INFO " error = %d\n", gh->gh_error); |
2115 | printk(KERN_INFO " gh_iflags ="); | |
b3b94faa DT |
2116 | for (x = 0; x < 32; x++) |
2117 | if (test_bit(x, &gh->gh_iflags)) | |
2118 | printk(" %u", x); | |
2119 | printk(" \n"); | |
d0dc80db | 2120 | print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip); |
b3b94faa DT |
2121 | |
2122 | error = 0; | |
2123 | ||
2124 | return error; | |
2125 | } | |
2126 | ||
2127 | /** | |
2128 | * dump_inode - print information about an inode | |
2129 | * @ip: the inode | |
2130 | * | |
2131 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2132 | */ | |
2133 | ||
2134 | static int dump_inode(struct gfs2_inode *ip) | |
2135 | { | |
2136 | unsigned int x; | |
2137 | int error = -ENOBUFS; | |
2138 | ||
d92a8d48 SW |
2139 | printk(KERN_INFO " Inode:\n"); |
2140 | printk(KERN_INFO " num = %llu %llu\n", | |
382066da SW |
2141 | (unsigned long long)ip->i_num.no_formal_ino, |
2142 | (unsigned long long)ip->i_num.no_addr); | |
d92a8d48 | 2143 | printk(KERN_INFO " type = %u\n", IF2DT(ip->i_di.di_mode)); |
d92a8d48 | 2144 | printk(KERN_INFO " i_flags ="); |
b3b94faa DT |
2145 | for (x = 0; x < 32; x++) |
2146 | if (test_bit(x, &ip->i_flags)) | |
2147 | printk(" %u", x); | |
2148 | printk(" \n"); | |
b3b94faa DT |
2149 | |
2150 | error = 0; | |
2151 | ||
2152 | return error; | |
2153 | } | |
2154 | ||
2155 | /** | |
2156 | * dump_glock - print information about a glock | |
2157 | * @gl: the glock | |
2158 | * @count: where we are in the buffer | |
2159 | * | |
2160 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2161 | */ | |
2162 | ||
2163 | static int dump_glock(struct gfs2_glock *gl) | |
2164 | { | |
2165 | struct gfs2_holder *gh; | |
2166 | unsigned int x; | |
2167 | int error = -ENOBUFS; | |
2168 | ||
2169 | spin_lock(&gl->gl_spin); | |
2170 | ||
320dd101 | 2171 | printk(KERN_INFO "Glock (%u, %llu)\n", gl->gl_name.ln_type, |
382066da | 2172 | (unsigned long long)gl->gl_name.ln_number); |
d92a8d48 | 2173 | printk(KERN_INFO " gl_flags ="); |
b3b94faa DT |
2174 | for (x = 0; x < 32; x++) |
2175 | if (test_bit(x, &gl->gl_flags)) | |
2176 | printk(" %u", x); | |
2177 | printk(" \n"); | |
d92a8d48 SW |
2178 | printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref.refcount)); |
2179 | printk(KERN_INFO " gl_state = %u\n", gl->gl_state); | |
320dd101 SW |
2180 | printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm); |
2181 | print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip); | |
d92a8d48 SW |
2182 | printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); |
2183 | printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); | |
2184 | printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); | |
2185 | printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no"); | |
2186 | printk(KERN_INFO " le = %s\n", | |
b3b94faa | 2187 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
d92a8d48 | 2188 | printk(KERN_INFO " reclaim = %s\n", |
b3b94faa DT |
2189 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); |
2190 | if (gl->gl_aspace) | |
d92a8d48 | 2191 | printk(KERN_INFO " aspace = %lu\n", |
b3b94faa DT |
2192 | gl->gl_aspace->i_mapping->nrpages); |
2193 | else | |
d92a8d48 SW |
2194 | printk(KERN_INFO " aspace = no\n"); |
2195 | printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count)); | |
b3b94faa DT |
2196 | if (gl->gl_req_gh) { |
2197 | error = dump_holder("Request", gl->gl_req_gh); | |
2198 | if (error) | |
2199 | goto out; | |
2200 | } | |
2201 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
2202 | error = dump_holder("Holder", gh); | |
2203 | if (error) | |
2204 | goto out; | |
2205 | } | |
2206 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { | |
2207 | error = dump_holder("Waiter1", gh); | |
2208 | if (error) | |
2209 | goto out; | |
2210 | } | |
2211 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
2212 | error = dump_holder("Waiter2", gh); | |
2213 | if (error) | |
2214 | goto out; | |
2215 | } | |
2216 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { | |
2217 | error = dump_holder("Waiter3", gh); | |
2218 | if (error) | |
2219 | goto out; | |
2220 | } | |
5c676f6d | 2221 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { |
b3b94faa DT |
2222 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && |
2223 | list_empty(&gl->gl_holders)) { | |
5c676f6d | 2224 | error = dump_inode(gl->gl_object); |
b3b94faa DT |
2225 | if (error) |
2226 | goto out; | |
2227 | } else { | |
2228 | error = -ENOBUFS; | |
d92a8d48 | 2229 | printk(KERN_INFO " Inode: busy\n"); |
b3b94faa DT |
2230 | } |
2231 | } | |
2232 | ||
2233 | error = 0; | |
2234 | ||
2235 | out: | |
2236 | spin_unlock(&gl->gl_spin); | |
2237 | ||
2238 | return error; | |
2239 | } | |
2240 | ||
2241 | /** | |
2242 | * gfs2_dump_lockstate - print out the current lockstate | |
2243 | * @sdp: the filesystem | |
2244 | * @ub: the buffer to copy the information into | |
2245 | * | |
2246 | * If @ub is NULL, dump the lockstate to the console. | |
2247 | * | |
2248 | */ | |
2249 | ||
08bc2dbc | 2250 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
b3b94faa DT |
2251 | { |
2252 | struct gfs2_gl_hash_bucket *bucket; | |
2253 | struct gfs2_glock *gl; | |
2254 | unsigned int x; | |
2255 | int error = 0; | |
2256 | ||
2257 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2258 | bucket = &sdp->sd_gl_hash[x]; | |
2259 | ||
2260 | read_lock(&bucket->hb_lock); | |
2261 | ||
2262 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
2263 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
2264 | continue; | |
2265 | ||
2266 | error = dump_glock(gl); | |
2267 | if (error) | |
2268 | break; | |
2269 | } | |
2270 | ||
2271 | read_unlock(&bucket->hb_lock); | |
2272 | ||
2273 | if (error) | |
2274 | break; | |
2275 | } | |
2276 | ||
2277 | ||
2278 | return error; | |
2279 | } | |
2280 |