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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 | |
e9fc2aa0 | 7 | * of the GNU General Public License version 2. |
b3b94faa DT |
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 | ||
d6a53727 | 86 | static unsigned int gl_hash(const struct lm_lockname *name) |
b3b94faa DT |
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 | { | |
b3b94faa DT |
153 | struct gfs2_gl_hash_bucket *bucket = gl->gl_bucket; |
154 | int rv = 0; | |
155 | ||
b3b94faa DT |
156 | write_lock(&bucket->hb_lock); |
157 | if (kref_put(&gl->gl_ref, kill_glock)) { | |
158 | list_del_init(&gl->gl_list); | |
159 | write_unlock(&bucket->hb_lock); | |
190562bd | 160 | BUG_ON(spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
161 | glock_free(gl); |
162 | rv = 1; | |
163 | goto out; | |
164 | } | |
165 | write_unlock(&bucket->hb_lock); | |
a2242db0 | 166 | out: |
b3b94faa DT |
167 | return rv; |
168 | } | |
169 | ||
170 | /** | |
171 | * queue_empty - check to see if a glock's queue is empty | |
172 | * @gl: the glock | |
173 | * @head: the head of the queue to check | |
174 | * | |
175 | * This function protects the list in the event that a process already | |
176 | * has a holder on the list and is adding a second holder for itself. | |
177 | * The glmutex lock is what generally prevents processes from working | |
178 | * on the same glock at once, but the special case of adding a second | |
179 | * holder for yourself ("recursive" locking) doesn't involve locking | |
180 | * glmutex, making the spin lock necessary. | |
181 | * | |
182 | * Returns: 1 if the queue is empty | |
183 | */ | |
184 | ||
185 | static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head) | |
186 | { | |
187 | int empty; | |
188 | spin_lock(&gl->gl_spin); | |
189 | empty = list_empty(head); | |
190 | spin_unlock(&gl->gl_spin); | |
191 | return empty; | |
192 | } | |
193 | ||
194 | /** | |
195 | * search_bucket() - Find struct gfs2_glock by lock number | |
196 | * @bucket: the bucket to search | |
197 | * @name: The lock name | |
198 | * | |
199 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
200 | */ | |
201 | ||
202 | static struct gfs2_glock *search_bucket(struct gfs2_gl_hash_bucket *bucket, | |
899be4d3 | 203 | const struct gfs2_sbd *sdp, |
d6a53727 | 204 | const struct lm_lockname *name) |
b3b94faa DT |
205 | { |
206 | struct gfs2_glock *gl; | |
207 | ||
208 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
209 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
210 | continue; | |
211 | if (!lm_name_equal(&gl->gl_name, name)) | |
212 | continue; | |
899be4d3 SW |
213 | if (gl->gl_sbd != sdp) |
214 | continue; | |
b3b94faa DT |
215 | |
216 | kref_get(&gl->gl_ref); | |
217 | ||
218 | return gl; | |
219 | } | |
220 | ||
221 | return NULL; | |
222 | } | |
223 | ||
224 | /** | |
225 | * gfs2_glock_find() - Find glock by lock number | |
226 | * @sdp: The GFS2 superblock | |
227 | * @name: The lock name | |
228 | * | |
229 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
230 | */ | |
231 | ||
08bc2dbc | 232 | static struct gfs2_glock *gfs2_glock_find(struct gfs2_sbd *sdp, |
d6a53727 | 233 | const struct lm_lockname *name) |
b3b94faa DT |
234 | { |
235 | struct gfs2_gl_hash_bucket *bucket = &sdp->sd_gl_hash[gl_hash(name)]; | |
236 | struct gfs2_glock *gl; | |
237 | ||
238 | read_lock(&bucket->hb_lock); | |
899be4d3 | 239 | gl = search_bucket(bucket, sdp, name); |
b3b94faa DT |
240 | read_unlock(&bucket->hb_lock); |
241 | ||
242 | return gl; | |
243 | } | |
244 | ||
245 | /** | |
246 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
247 | * @sdp: The GFS2 superblock | |
248 | * @number: the lock number | |
249 | * @glops: The glock_operations to use | |
250 | * @create: If 0, don't create the glock if it doesn't exist | |
251 | * @glp: the glock is returned here | |
252 | * | |
253 | * This does not lock a glock, just finds/creates structures for one. | |
254 | * | |
255 | * Returns: errno | |
256 | */ | |
257 | ||
258 | int gfs2_glock_get(struct gfs2_sbd *sdp, uint64_t number, | |
8fb4b536 | 259 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
260 | struct gfs2_glock **glp) |
261 | { | |
262 | struct lm_lockname name; | |
263 | struct gfs2_glock *gl, *tmp; | |
264 | struct gfs2_gl_hash_bucket *bucket; | |
265 | int error; | |
266 | ||
267 | name.ln_number = number; | |
268 | name.ln_type = glops->go_type; | |
269 | bucket = &sdp->sd_gl_hash[gl_hash(&name)]; | |
270 | ||
271 | read_lock(&bucket->hb_lock); | |
899be4d3 | 272 | gl = search_bucket(bucket, sdp, &name); |
b3b94faa DT |
273 | read_unlock(&bucket->hb_lock); |
274 | ||
275 | if (gl || !create) { | |
276 | *glp = gl; | |
277 | return 0; | |
278 | } | |
279 | ||
280 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); | |
281 | if (!gl) | |
282 | return -ENOMEM; | |
283 | ||
ec45d9f5 | 284 | gl->gl_flags = 0; |
b3b94faa DT |
285 | gl->gl_name = name; |
286 | kref_init(&gl->gl_ref); | |
b3b94faa | 287 | gl->gl_state = LM_ST_UNLOCKED; |
320dd101 SW |
288 | gl->gl_owner = NULL; |
289 | gl->gl_ip = 0; | |
b3b94faa | 290 | gl->gl_ops = glops; |
ec45d9f5 SW |
291 | gl->gl_req_gh = NULL; |
292 | gl->gl_req_bh = NULL; | |
293 | gl->gl_vn = 0; | |
294 | gl->gl_stamp = jiffies; | |
295 | gl->gl_object = NULL; | |
b3b94faa | 296 | gl->gl_bucket = bucket; |
b3b94faa | 297 | gl->gl_sbd = sdp; |
ec45d9f5 | 298 | gl->gl_aspace = NULL; |
b3b94faa | 299 | lops_init_le(&gl->gl_le, &gfs2_glock_lops); |
b3b94faa DT |
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. */ | |
50299965 | 303 | if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) { |
b3b94faa DT |
304 | gl->gl_aspace = gfs2_aspace_get(sdp); |
305 | if (!gl->gl_aspace) { | |
306 | error = -ENOMEM; | |
307 | goto fail; | |
308 | } | |
309 | } | |
310 | ||
311 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
312 | if (error) | |
313 | goto fail_aspace; | |
314 | ||
b3b94faa | 315 | write_lock(&bucket->hb_lock); |
899be4d3 | 316 | tmp = search_bucket(bucket, sdp, &name); |
b3b94faa DT |
317 | if (tmp) { |
318 | write_unlock(&bucket->hb_lock); | |
319 | glock_free(gl); | |
320 | gl = tmp; | |
321 | } else { | |
322 | list_add_tail(&gl->gl_list, &bucket->hb_list); | |
323 | write_unlock(&bucket->hb_lock); | |
324 | } | |
325 | ||
326 | *glp = gl; | |
327 | ||
328 | return 0; | |
329 | ||
ec45d9f5 | 330 | fail_aspace: |
b3b94faa DT |
331 | if (gl->gl_aspace) |
332 | gfs2_aspace_put(gl->gl_aspace); | |
ec45d9f5 | 333 | fail: |
b3b94faa | 334 | kmem_cache_free(gfs2_glock_cachep, gl); |
b3b94faa DT |
335 | return error; |
336 | } | |
337 | ||
338 | /** | |
339 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
340 | * @gl: the glock | |
341 | * @state: the state we're requesting | |
342 | * @flags: the modifier flags | |
343 | * @gh: the holder structure | |
344 | * | |
345 | */ | |
346 | ||
190562bd | 347 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
348 | struct gfs2_holder *gh) |
349 | { | |
350 | INIT_LIST_HEAD(&gh->gh_list); | |
351 | gh->gh_gl = gl; | |
d0dc80db | 352 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
190562bd | 353 | gh->gh_owner = current; |
b3b94faa DT |
354 | gh->gh_state = state; |
355 | gh->gh_flags = flags; | |
356 | gh->gh_error = 0; | |
357 | gh->gh_iflags = 0; | |
358 | init_completion(&gh->gh_wait); | |
359 | ||
360 | if (gh->gh_state == LM_ST_EXCLUSIVE) | |
361 | gh->gh_flags |= GL_LOCAL_EXCL; | |
362 | ||
363 | gfs2_glock_hold(gl); | |
364 | } | |
365 | ||
366 | /** | |
367 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
368 | * @state: the state we're requesting | |
369 | * @flags: the modifier flags | |
370 | * @gh: the holder structure | |
371 | * | |
372 | * Don't mess with the glock. | |
373 | * | |
374 | */ | |
375 | ||
190562bd | 376 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
377 | { |
378 | gh->gh_state = state; | |
579b78a4 | 379 | gh->gh_flags = flags; |
b3b94faa DT |
380 | if (gh->gh_state == LM_ST_EXCLUSIVE) |
381 | gh->gh_flags |= GL_LOCAL_EXCL; | |
382 | ||
383 | gh->gh_iflags &= 1 << HIF_ALLOCED; | |
d0dc80db | 384 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
385 | } |
386 | ||
387 | /** | |
388 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
389 | * @gh: the holder structure | |
390 | * | |
391 | */ | |
392 | ||
393 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
394 | { | |
395 | gfs2_glock_put(gh->gh_gl); | |
396 | gh->gh_gl = NULL; | |
d0dc80db | 397 | gh->gh_ip = 0; |
b3b94faa DT |
398 | } |
399 | ||
400 | /** | |
401 | * gfs2_holder_get - get a struct gfs2_holder structure | |
402 | * @gl: the glock | |
403 | * @state: the state we're requesting | |
404 | * @flags: the modifier flags | |
af18ddb8 | 405 | * @gfp_flags: |
b3b94faa DT |
406 | * |
407 | * Figure out how big an impact this function has. Either: | |
408 | * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd | |
409 | * 2) Leave it like it is | |
410 | * | |
411 | * Returns: the holder structure, NULL on ENOMEM | |
412 | */ | |
413 | ||
08bc2dbc AB |
414 | static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, |
415 | unsigned int state, | |
416 | int flags, gfp_t gfp_flags) | |
b3b94faa DT |
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); | |
d0dc80db | 426 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
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 | ||
08bc2dbc | 436 | static void gfs2_holder_put(struct gfs2_holder *gh) |
b3b94faa DT |
437 | { |
438 | gfs2_holder_uninit(gh); | |
439 | kfree(gh); | |
440 | } | |
441 | ||
b3b94faa DT |
442 | /** |
443 | * rq_mutex - process a mutex request in the queue | |
444 | * @gh: the glock holder | |
445 | * | |
446 | * Returns: 1 if the queue is blocked | |
447 | */ | |
448 | ||
449 | static int rq_mutex(struct gfs2_holder *gh) | |
450 | { | |
451 | struct gfs2_glock *gl = gh->gh_gl; | |
452 | ||
453 | list_del_init(&gh->gh_list); | |
454 | /* gh->gh_error never examined. */ | |
455 | set_bit(GLF_LOCK, &gl->gl_flags); | |
456 | complete(&gh->gh_wait); | |
457 | ||
458 | return 1; | |
459 | } | |
460 | ||
461 | /** | |
462 | * rq_promote - process a promote request in the queue | |
463 | * @gh: the glock holder | |
464 | * | |
465 | * Acquire a new inter-node lock, or change a lock state to more restrictive. | |
466 | * | |
467 | * Returns: 1 if the queue is blocked | |
468 | */ | |
469 | ||
470 | static int rq_promote(struct gfs2_holder *gh) | |
471 | { | |
472 | struct gfs2_glock *gl = gh->gh_gl; | |
473 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 474 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
475 | |
476 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
477 | if (list_empty(&gl->gl_holders)) { | |
478 | gl->gl_req_gh = gh; | |
479 | set_bit(GLF_LOCK, &gl->gl_flags); | |
480 | spin_unlock(&gl->gl_spin); | |
481 | ||
482 | if (atomic_read(&sdp->sd_reclaim_count) > | |
483 | gfs2_tune_get(sdp, gt_reclaim_limit) && | |
484 | !(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
485 | gfs2_reclaim_glock(sdp); | |
486 | gfs2_reclaim_glock(sdp); | |
487 | } | |
488 | ||
ec45d9f5 | 489 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); |
b3b94faa DT |
490 | spin_lock(&gl->gl_spin); |
491 | } | |
492 | return 1; | |
493 | } | |
494 | ||
495 | if (list_empty(&gl->gl_holders)) { | |
496 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
497 | set_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
498 | } else { |
499 | struct gfs2_holder *next_gh; | |
500 | if (gh->gh_flags & GL_LOCAL_EXCL) | |
501 | return 1; | |
502 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, | |
503 | gh_list); | |
504 | if (next_gh->gh_flags & GL_LOCAL_EXCL) | |
505 | return 1; | |
b3b94faa DT |
506 | } |
507 | ||
508 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
509 | gh->gh_error = 0; | |
510 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
511 | ||
b3b94faa DT |
512 | complete(&gh->gh_wait); |
513 | ||
514 | return 0; | |
515 | } | |
516 | ||
517 | /** | |
518 | * rq_demote - process a demote request in the queue | |
519 | * @gh: the glock holder | |
520 | * | |
521 | * Returns: 1 if the queue is blocked | |
522 | */ | |
523 | ||
524 | static int rq_demote(struct gfs2_holder *gh) | |
525 | { | |
526 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 527 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
528 | |
529 | if (!list_empty(&gl->gl_holders)) | |
530 | return 1; | |
531 | ||
532 | if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { | |
533 | list_del_init(&gh->gh_list); | |
534 | gh->gh_error = 0; | |
535 | spin_unlock(&gl->gl_spin); | |
536 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
537 | gfs2_holder_put(gh); | |
538 | else | |
539 | complete(&gh->gh_wait); | |
540 | spin_lock(&gl->gl_spin); | |
541 | } else { | |
542 | gl->gl_req_gh = gh; | |
543 | set_bit(GLF_LOCK, &gl->gl_flags); | |
544 | spin_unlock(&gl->gl_spin); | |
545 | ||
546 | if (gh->gh_state == LM_ST_UNLOCKED || | |
547 | gl->gl_state != LM_ST_EXCLUSIVE) | |
548 | glops->go_drop_th(gl); | |
549 | else | |
550 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); | |
551 | ||
552 | spin_lock(&gl->gl_spin); | |
553 | } | |
554 | ||
555 | return 0; | |
556 | } | |
557 | ||
558 | /** | |
559 | * rq_greedy - process a queued request to drop greedy status | |
560 | * @gh: the glock holder | |
561 | * | |
562 | * Returns: 1 if the queue is blocked | |
563 | */ | |
564 | ||
565 | static int rq_greedy(struct gfs2_holder *gh) | |
566 | { | |
567 | struct gfs2_glock *gl = gh->gh_gl; | |
568 | ||
569 | list_del_init(&gh->gh_list); | |
570 | /* gh->gh_error never examined. */ | |
571 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
572 | spin_unlock(&gl->gl_spin); | |
573 | ||
574 | gfs2_holder_uninit(gh); | |
575 | kfree(container_of(gh, struct greedy, gr_gh)); | |
576 | ||
577 | spin_lock(&gl->gl_spin); | |
578 | ||
579 | return 0; | |
580 | } | |
581 | ||
582 | /** | |
583 | * run_queue - process holder structures on a glock | |
584 | * @gl: the glock | |
585 | * | |
586 | */ | |
b3b94faa DT |
587 | static void run_queue(struct gfs2_glock *gl) |
588 | { | |
589 | struct gfs2_holder *gh; | |
590 | int blocked = 1; | |
591 | ||
592 | for (;;) { | |
593 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
594 | break; | |
595 | ||
596 | if (!list_empty(&gl->gl_waiters1)) { | |
597 | gh = list_entry(gl->gl_waiters1.next, | |
598 | struct gfs2_holder, gh_list); | |
599 | ||
600 | if (test_bit(HIF_MUTEX, &gh->gh_iflags)) | |
601 | blocked = rq_mutex(gh); | |
602 | else | |
603 | gfs2_assert_warn(gl->gl_sbd, 0); | |
604 | ||
605 | } else if (!list_empty(&gl->gl_waiters2) && | |
606 | !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { | |
607 | gh = list_entry(gl->gl_waiters2.next, | |
608 | struct gfs2_holder, gh_list); | |
609 | ||
610 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) | |
611 | blocked = rq_demote(gh); | |
612 | else if (test_bit(HIF_GREEDY, &gh->gh_iflags)) | |
613 | blocked = rq_greedy(gh); | |
614 | else | |
615 | gfs2_assert_warn(gl->gl_sbd, 0); | |
616 | ||
617 | } else if (!list_empty(&gl->gl_waiters3)) { | |
618 | gh = list_entry(gl->gl_waiters3.next, | |
619 | struct gfs2_holder, gh_list); | |
620 | ||
621 | if (test_bit(HIF_PROMOTE, &gh->gh_iflags)) | |
622 | blocked = rq_promote(gh); | |
623 | else | |
624 | gfs2_assert_warn(gl->gl_sbd, 0); | |
625 | ||
626 | } else | |
627 | break; | |
628 | ||
629 | if (blocked) | |
630 | break; | |
631 | } | |
632 | } | |
633 | ||
634 | /** | |
635 | * gfs2_glmutex_lock - acquire a local lock on a glock | |
636 | * @gl: the glock | |
637 | * | |
638 | * Gives caller exclusive access to manipulate a glock structure. | |
639 | */ | |
640 | ||
feaa7bba | 641 | static void gfs2_glmutex_lock(struct gfs2_glock *gl) |
b3b94faa DT |
642 | { |
643 | struct gfs2_holder gh; | |
644 | ||
645 | gfs2_holder_init(gl, 0, 0, &gh); | |
646 | set_bit(HIF_MUTEX, &gh.gh_iflags); | |
647 | ||
648 | spin_lock(&gl->gl_spin); | |
649 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
650 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); | |
320dd101 SW |
651 | else { |
652 | gl->gl_owner = current; | |
653 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
b3b94faa | 654 | complete(&gh.gh_wait); |
320dd101 | 655 | } |
b3b94faa DT |
656 | spin_unlock(&gl->gl_spin); |
657 | ||
658 | wait_for_completion(&gh.gh_wait); | |
659 | gfs2_holder_uninit(&gh); | |
660 | } | |
661 | ||
662 | /** | |
663 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock | |
664 | * @gl: the glock | |
665 | * | |
666 | * Returns: 1 if the glock is acquired | |
667 | */ | |
668 | ||
08bc2dbc | 669 | static int gfs2_glmutex_trylock(struct gfs2_glock *gl) |
b3b94faa DT |
670 | { |
671 | int acquired = 1; | |
672 | ||
673 | spin_lock(&gl->gl_spin); | |
674 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
675 | acquired = 0; | |
320dd101 SW |
676 | else { |
677 | gl->gl_owner = current; | |
678 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
679 | } | |
b3b94faa DT |
680 | spin_unlock(&gl->gl_spin); |
681 | ||
682 | return acquired; | |
683 | } | |
684 | ||
685 | /** | |
686 | * gfs2_glmutex_unlock - release a local lock on a glock | |
687 | * @gl: the glock | |
688 | * | |
689 | */ | |
690 | ||
feaa7bba | 691 | static void gfs2_glmutex_unlock(struct gfs2_glock *gl) |
b3b94faa DT |
692 | { |
693 | spin_lock(&gl->gl_spin); | |
694 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
320dd101 SW |
695 | gl->gl_owner = NULL; |
696 | gl->gl_ip = 0; | |
b3b94faa | 697 | run_queue(gl); |
190562bd | 698 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
699 | spin_unlock(&gl->gl_spin); |
700 | } | |
701 | ||
702 | /** | |
703 | * handle_callback - add a demote request to a lock's queue | |
704 | * @gl: the glock | |
705 | * @state: the state the caller wants us to change to | |
706 | * | |
af18ddb8 | 707 | * Note: This may fail sliently if we are out of memory. |
b3b94faa DT |
708 | */ |
709 | ||
710 | static void handle_callback(struct gfs2_glock *gl, unsigned int state) | |
711 | { | |
712 | struct gfs2_holder *gh, *new_gh = NULL; | |
713 | ||
feaa7bba | 714 | restart: |
b3b94faa DT |
715 | spin_lock(&gl->gl_spin); |
716 | ||
717 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
718 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && | |
719 | gl->gl_req_gh != gh) { | |
720 | if (gh->gh_state != state) | |
721 | gh->gh_state = LM_ST_UNLOCKED; | |
722 | goto out; | |
723 | } | |
724 | } | |
725 | ||
726 | if (new_gh) { | |
727 | list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); | |
728 | new_gh = NULL; | |
729 | } else { | |
730 | spin_unlock(&gl->gl_spin); | |
731 | ||
af18ddb8 SW |
732 | new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_KERNEL); |
733 | if (!new_gh) | |
734 | return; | |
b3b94faa DT |
735 | set_bit(HIF_DEMOTE, &new_gh->gh_iflags); |
736 | set_bit(HIF_DEALLOC, &new_gh->gh_iflags); | |
737 | ||
738 | goto restart; | |
739 | } | |
740 | ||
feaa7bba | 741 | out: |
b3b94faa DT |
742 | spin_unlock(&gl->gl_spin); |
743 | ||
744 | if (new_gh) | |
745 | gfs2_holder_put(new_gh); | |
746 | } | |
747 | ||
feaa7bba SW |
748 | void gfs2_glock_inode_squish(struct inode *inode) |
749 | { | |
750 | struct gfs2_holder gh; | |
751 | struct gfs2_glock *gl = GFS2_I(inode)->i_gl; | |
752 | gfs2_holder_init(gl, LM_ST_UNLOCKED, 0, &gh); | |
753 | set_bit(HIF_DEMOTE, &gh.gh_iflags); | |
754 | spin_lock(&gl->gl_spin); | |
755 | gfs2_assert(inode->i_sb->s_fs_info, list_empty(&gl->gl_holders)); | |
756 | list_add_tail(&gh.gh_list, &gl->gl_waiters2); | |
757 | run_queue(gl); | |
758 | spin_unlock(&gl->gl_spin); | |
5dd9feaf | 759 | wait_for_completion(&gh.gh_wait); |
feaa7bba SW |
760 | gfs2_holder_uninit(&gh); |
761 | } | |
762 | ||
b3b94faa DT |
763 | /** |
764 | * state_change - record that the glock is now in a different state | |
765 | * @gl: the glock | |
766 | * @new_state the new state | |
767 | * | |
768 | */ | |
769 | ||
770 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
771 | { | |
b3b94faa DT |
772 | int held1, held2; |
773 | ||
774 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
775 | held2 = (new_state != LM_ST_UNLOCKED); | |
776 | ||
777 | if (held1 != held2) { | |
6a6b3d01 | 778 | if (held2) |
b3b94faa | 779 | gfs2_glock_hold(gl); |
6a6b3d01 | 780 | else |
b3b94faa | 781 | gfs2_glock_put(gl); |
b3b94faa DT |
782 | } |
783 | ||
784 | gl->gl_state = new_state; | |
785 | } | |
786 | ||
787 | /** | |
788 | * xmote_bh - Called after the lock module is done acquiring a lock | |
789 | * @gl: The glock in question | |
790 | * @ret: the int returned from the lock module | |
791 | * | |
792 | */ | |
793 | ||
794 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) | |
795 | { | |
796 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 797 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
798 | struct gfs2_holder *gh = gl->gl_req_gh; |
799 | int prev_state = gl->gl_state; | |
800 | int op_done = 1; | |
801 | ||
802 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
803 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
804 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); | |
805 | ||
806 | state_change(gl, ret & LM_OUT_ST_MASK); | |
807 | ||
808 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { | |
809 | if (glops->go_inval) | |
810 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
811 | } else if (gl->gl_state == LM_ST_DEFERRED) { | |
812 | /* We might not want to do this here. | |
813 | Look at moving to the inode glops. */ | |
814 | if (glops->go_inval) | |
815 | glops->go_inval(gl, DIO_DATA); | |
816 | } | |
817 | ||
818 | /* Deal with each possible exit condition */ | |
819 | ||
820 | if (!gh) | |
821 | gl->gl_stamp = jiffies; | |
b3b94faa DT |
822 | else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
823 | spin_lock(&gl->gl_spin); | |
824 | list_del_init(&gh->gh_list); | |
825 | gh->gh_error = -EIO; | |
b3b94faa | 826 | spin_unlock(&gl->gl_spin); |
b3b94faa DT |
827 | } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { |
828 | spin_lock(&gl->gl_spin); | |
829 | list_del_init(&gh->gh_list); | |
830 | if (gl->gl_state == gh->gh_state || | |
831 | gl->gl_state == LM_ST_UNLOCKED) | |
832 | gh->gh_error = 0; | |
833 | else { | |
834 | if (gfs2_assert_warn(sdp, gh->gh_flags & | |
835 | (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) | |
836 | fs_warn(sdp, "ret = 0x%.8X\n", ret); | |
837 | gh->gh_error = GLR_TRYFAILED; | |
838 | } | |
839 | spin_unlock(&gl->gl_spin); | |
840 | ||
841 | if (ret & LM_OUT_CANCELED) | |
50299965 | 842 | handle_callback(gl, LM_ST_UNLOCKED); |
b3b94faa DT |
843 | |
844 | } else if (ret & LM_OUT_CANCELED) { | |
845 | spin_lock(&gl->gl_spin); | |
846 | list_del_init(&gh->gh_list); | |
847 | gh->gh_error = GLR_CANCELED; | |
b3b94faa DT |
848 | spin_unlock(&gl->gl_spin); |
849 | ||
850 | } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
851 | spin_lock(&gl->gl_spin); | |
852 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
853 | gh->gh_error = 0; | |
854 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
855 | spin_unlock(&gl->gl_spin); | |
856 | ||
857 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
858 | ||
859 | op_done = 0; | |
860 | ||
861 | } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
862 | spin_lock(&gl->gl_spin); | |
863 | list_del_init(&gh->gh_list); | |
864 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
865 | spin_unlock(&gl->gl_spin); |
866 | ||
867 | } else { | |
868 | if (gfs2_assert_withdraw(sdp, 0) == -1) | |
869 | fs_err(sdp, "ret = 0x%.8X\n", ret); | |
870 | } | |
871 | ||
872 | if (glops->go_xmote_bh) | |
873 | glops->go_xmote_bh(gl); | |
874 | ||
875 | if (op_done) { | |
876 | spin_lock(&gl->gl_spin); | |
877 | gl->gl_req_gh = NULL; | |
878 | gl->gl_req_bh = NULL; | |
879 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
880 | run_queue(gl); | |
881 | spin_unlock(&gl->gl_spin); | |
882 | } | |
883 | ||
884 | gfs2_glock_put(gl); | |
885 | ||
886 | if (gh) { | |
887 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
888 | gfs2_holder_put(gh); | |
889 | else | |
890 | complete(&gh->gh_wait); | |
891 | } | |
892 | } | |
893 | ||
894 | /** | |
895 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock | |
896 | * @gl: The glock in question | |
897 | * @state: the requested state | |
898 | * @flags: modifier flags to the lock call | |
899 | * | |
900 | */ | |
901 | ||
902 | void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags) | |
903 | { | |
904 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 905 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
906 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | |
907 | LM_FLAG_NOEXP | LM_FLAG_ANY | | |
908 | LM_FLAG_PRIORITY); | |
909 | unsigned int lck_ret; | |
910 | ||
911 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
912 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
913 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); | |
914 | gfs2_assert_warn(sdp, state != gl->gl_state); | |
915 | ||
50299965 SW |
916 | if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync) |
917 | glops->go_sync(gl, DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
b3b94faa DT |
918 | |
919 | gfs2_glock_hold(gl); | |
920 | gl->gl_req_bh = xmote_bh; | |
921 | ||
ec45d9f5 | 922 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags); |
b3b94faa DT |
923 | |
924 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) | |
925 | return; | |
926 | ||
927 | if (lck_ret & LM_OUT_ASYNC) | |
928 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); | |
929 | else | |
930 | xmote_bh(gl, lck_ret); | |
931 | } | |
932 | ||
933 | /** | |
934 | * drop_bh - Called after a lock module unlock completes | |
935 | * @gl: the glock | |
936 | * @ret: the return status | |
937 | * | |
938 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) | |
939 | * Doesn't drop the reference on the glock the top half took out | |
940 | * | |
941 | */ | |
942 | ||
943 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) | |
944 | { | |
945 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 946 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
947 | struct gfs2_holder *gh = gl->gl_req_gh; |
948 | ||
949 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
950 | ||
951 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
952 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
953 | gfs2_assert_warn(sdp, !ret); | |
954 | ||
955 | state_change(gl, LM_ST_UNLOCKED); | |
956 | ||
957 | if (glops->go_inval) | |
958 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
959 | ||
960 | if (gh) { | |
961 | spin_lock(&gl->gl_spin); | |
962 | list_del_init(&gh->gh_list); | |
963 | gh->gh_error = 0; | |
964 | spin_unlock(&gl->gl_spin); | |
965 | } | |
966 | ||
967 | if (glops->go_drop_bh) | |
968 | glops->go_drop_bh(gl); | |
969 | ||
970 | spin_lock(&gl->gl_spin); | |
971 | gl->gl_req_gh = NULL; | |
972 | gl->gl_req_bh = NULL; | |
973 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
974 | run_queue(gl); | |
975 | spin_unlock(&gl->gl_spin); | |
976 | ||
977 | gfs2_glock_put(gl); | |
978 | ||
979 | if (gh) { | |
980 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
981 | gfs2_holder_put(gh); | |
982 | else | |
983 | complete(&gh->gh_wait); | |
984 | } | |
985 | } | |
986 | ||
987 | /** | |
988 | * gfs2_glock_drop_th - call into the lock module to unlock a lock | |
989 | * @gl: the glock | |
990 | * | |
991 | */ | |
992 | ||
993 | void gfs2_glock_drop_th(struct gfs2_glock *gl) | |
994 | { | |
995 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 996 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
997 | unsigned int ret; |
998 | ||
999 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1000 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
1001 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); | |
1002 | ||
50299965 SW |
1003 | if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync) |
1004 | glops->go_sync(gl, DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
b3b94faa DT |
1005 | |
1006 | gfs2_glock_hold(gl); | |
1007 | gl->gl_req_bh = drop_bh; | |
1008 | ||
b3b94faa DT |
1009 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
1010 | ||
1011 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) | |
1012 | return; | |
1013 | ||
1014 | if (!ret) | |
1015 | drop_bh(gl, ret); | |
1016 | else | |
1017 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); | |
1018 | } | |
1019 | ||
1020 | /** | |
1021 | * do_cancels - cancel requests for locks stuck waiting on an expire flag | |
1022 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock | |
1023 | * | |
1024 | * Don't cancel GL_NOCANCEL requests. | |
1025 | */ | |
1026 | ||
1027 | static void do_cancels(struct gfs2_holder *gh) | |
1028 | { | |
1029 | struct gfs2_glock *gl = gh->gh_gl; | |
1030 | ||
1031 | spin_lock(&gl->gl_spin); | |
1032 | ||
1033 | while (gl->gl_req_gh != gh && | |
1034 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1035 | !list_empty(&gh->gh_list)) { | |
50299965 SW |
1036 | if (gl->gl_req_bh && !(gl->gl_req_gh && |
1037 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { | |
b3b94faa DT |
1038 | spin_unlock(&gl->gl_spin); |
1039 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); | |
1040 | msleep(100); | |
1041 | spin_lock(&gl->gl_spin); | |
1042 | } else { | |
1043 | spin_unlock(&gl->gl_spin); | |
1044 | msleep(100); | |
1045 | spin_lock(&gl->gl_spin); | |
1046 | } | |
1047 | } | |
1048 | ||
1049 | spin_unlock(&gl->gl_spin); | |
1050 | } | |
1051 | ||
1052 | /** | |
1053 | * glock_wait_internal - wait on a glock acquisition | |
1054 | * @gh: the glock holder | |
1055 | * | |
1056 | * Returns: 0 on success | |
1057 | */ | |
1058 | ||
1059 | static int glock_wait_internal(struct gfs2_holder *gh) | |
1060 | { | |
1061 | struct gfs2_glock *gl = gh->gh_gl; | |
1062 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1063 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1064 | |
1065 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) | |
1066 | return -EIO; | |
1067 | ||
1068 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
1069 | spin_lock(&gl->gl_spin); | |
1070 | if (gl->gl_req_gh != gh && | |
1071 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1072 | !list_empty(&gh->gh_list)) { | |
1073 | list_del_init(&gh->gh_list); | |
1074 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
1075 | run_queue(gl); |
1076 | spin_unlock(&gl->gl_spin); | |
1077 | return gh->gh_error; | |
1078 | } | |
1079 | spin_unlock(&gl->gl_spin); | |
1080 | } | |
1081 | ||
1082 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1083 | do_cancels(gh); | |
1084 | ||
1085 | wait_for_completion(&gh->gh_wait); | |
1086 | ||
1087 | if (gh->gh_error) | |
1088 | return gh->gh_error; | |
1089 | ||
1090 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); | |
1091 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, | |
1092 | gh->gh_state, | |
1093 | gh->gh_flags)); | |
1094 | ||
1095 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { | |
1096 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1097 | ||
1098 | if (glops->go_lock) { | |
1099 | gh->gh_error = glops->go_lock(gh); | |
1100 | if (gh->gh_error) { | |
1101 | spin_lock(&gl->gl_spin); | |
1102 | list_del_init(&gh->gh_list); | |
b3b94faa DT |
1103 | spin_unlock(&gl->gl_spin); |
1104 | } | |
1105 | } | |
1106 | ||
1107 | spin_lock(&gl->gl_spin); | |
1108 | gl->gl_req_gh = NULL; | |
1109 | gl->gl_req_bh = NULL; | |
1110 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
1111 | run_queue(gl); |
1112 | spin_unlock(&gl->gl_spin); | |
1113 | } | |
1114 | ||
1115 | return gh->gh_error; | |
1116 | } | |
1117 | ||
1118 | static inline struct gfs2_holder * | |
1119 | find_holder_by_owner(struct list_head *head, struct task_struct *owner) | |
1120 | { | |
1121 | struct gfs2_holder *gh; | |
1122 | ||
1123 | list_for_each_entry(gh, head, gh_list) { | |
1124 | if (gh->gh_owner == owner) | |
1125 | return gh; | |
1126 | } | |
1127 | ||
1128 | return NULL; | |
1129 | } | |
1130 | ||
b3b94faa DT |
1131 | /** |
1132 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
1133 | * @gh: the holder structure to add | |
1134 | * | |
1135 | */ | |
1136 | ||
1137 | static void add_to_queue(struct gfs2_holder *gh) | |
1138 | { | |
1139 | struct gfs2_glock *gl = gh->gh_gl; | |
1140 | struct gfs2_holder *existing; | |
1141 | ||
190562bd SW |
1142 | BUG_ON(!gh->gh_owner); |
1143 | ||
b3b94faa DT |
1144 | existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner); |
1145 | if (existing) { | |
5965b1f4 | 1146 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
86384605 AD |
1147 | printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid); |
1148 | printk(KERN_INFO "lock type : %d lock state : %d\n", | |
1149 | existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state); | |
5965b1f4 | 1150 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); |
86384605 AD |
1151 | printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid); |
1152 | printk(KERN_INFO "lock type : %d lock state : %d\n", | |
1153 | gl->gl_name.ln_type, gl->gl_state); | |
5965b1f4 | 1154 | BUG(); |
b3b94faa DT |
1155 | } |
1156 | ||
1157 | existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner); | |
1158 | if (existing) { | |
5965b1f4 SW |
1159 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
1160 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); | |
1161 | BUG(); | |
b3b94faa DT |
1162 | } |
1163 | ||
b3b94faa DT |
1164 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
1165 | list_add(&gh->gh_list, &gl->gl_waiters3); | |
1166 | else | |
1167 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); | |
1168 | } | |
1169 | ||
1170 | /** | |
1171 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1172 | * @gh: the holder structure | |
1173 | * | |
1174 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1175 | * | |
1176 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1177 | */ | |
1178 | ||
1179 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1180 | { | |
1181 | struct gfs2_glock *gl = gh->gh_gl; | |
1182 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1183 | int error = 0; | |
1184 | ||
320dd101 | 1185 | restart: |
b3b94faa DT |
1186 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
1187 | set_bit(HIF_ABORTED, &gh->gh_iflags); | |
1188 | return -EIO; | |
1189 | } | |
1190 | ||
1191 | set_bit(HIF_PROMOTE, &gh->gh_iflags); | |
1192 | ||
1193 | spin_lock(&gl->gl_spin); | |
1194 | add_to_queue(gh); | |
1195 | run_queue(gl); | |
1196 | spin_unlock(&gl->gl_spin); | |
1197 | ||
1198 | if (!(gh->gh_flags & GL_ASYNC)) { | |
1199 | error = glock_wait_internal(gh); | |
1200 | if (error == GLR_CANCELED) { | |
190562bd | 1201 | msleep(100); |
b3b94faa DT |
1202 | goto restart; |
1203 | } | |
1204 | } | |
1205 | ||
1206 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
1207 | ||
320dd101 SW |
1208 | if (error == GLR_TRYFAILED && (gh->gh_flags & GL_DUMP)) |
1209 | dump_glock(gl); | |
1210 | ||
b3b94faa DT |
1211 | return error; |
1212 | } | |
1213 | ||
1214 | /** | |
1215 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1216 | * @gh: the holder | |
1217 | * | |
1218 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1219 | */ | |
1220 | ||
1221 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1222 | { | |
1223 | struct gfs2_glock *gl = gh->gh_gl; | |
1224 | int ready = 0; | |
1225 | ||
1226 | spin_lock(&gl->gl_spin); | |
1227 | ||
1228 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1229 | ready = 1; | |
1230 | else if (list_empty(&gh->gh_list)) { | |
1231 | if (gh->gh_error == GLR_CANCELED) { | |
1232 | spin_unlock(&gl->gl_spin); | |
190562bd | 1233 | msleep(100); |
b3b94faa DT |
1234 | if (gfs2_glock_nq(gh)) |
1235 | return 1; | |
1236 | return 0; | |
1237 | } else | |
1238 | ready = 1; | |
1239 | } | |
1240 | ||
1241 | spin_unlock(&gl->gl_spin); | |
1242 | ||
1243 | return ready; | |
1244 | } | |
1245 | ||
1246 | /** | |
1247 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC | |
1248 | * @gh: the holder structure | |
1249 | * | |
1250 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1251 | */ | |
1252 | ||
1253 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
1254 | { | |
1255 | int error; | |
1256 | ||
1257 | error = glock_wait_internal(gh); | |
1258 | if (error == GLR_CANCELED) { | |
190562bd | 1259 | msleep(100); |
b3b94faa DT |
1260 | gh->gh_flags &= ~GL_ASYNC; |
1261 | error = gfs2_glock_nq(gh); | |
1262 | } | |
1263 | ||
1264 | return error; | |
1265 | } | |
1266 | ||
1267 | /** | |
1268 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1269 | * @gh: the glock holder | |
1270 | * | |
1271 | */ | |
1272 | ||
1273 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1274 | { | |
1275 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1276 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa | 1277 | |
b3b94faa DT |
1278 | if (gh->gh_flags & GL_NOCACHE) |
1279 | handle_callback(gl, LM_ST_UNLOCKED); | |
1280 | ||
1281 | gfs2_glmutex_lock(gl); | |
1282 | ||
1283 | spin_lock(&gl->gl_spin); | |
1284 | list_del_init(&gh->gh_list); | |
1285 | ||
1286 | if (list_empty(&gl->gl_holders)) { | |
1287 | spin_unlock(&gl->gl_spin); | |
1288 | ||
1289 | if (glops->go_unlock) | |
1290 | glops->go_unlock(gh); | |
1291 | ||
b3b94faa DT |
1292 | gl->gl_stamp = jiffies; |
1293 | ||
1294 | spin_lock(&gl->gl_spin); | |
1295 | } | |
1296 | ||
1297 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1298 | run_queue(gl); | |
1299 | spin_unlock(&gl->gl_spin); | |
1300 | } | |
1301 | ||
1302 | /** | |
1303 | * gfs2_glock_prefetch - Try to prefetch a glock | |
1304 | * @gl: the glock | |
1305 | * @state: the state to prefetch in | |
1306 | * @flags: flags passed to go_xmote_th() | |
1307 | * | |
1308 | */ | |
1309 | ||
08bc2dbc AB |
1310 | static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state, |
1311 | int flags) | |
b3b94faa | 1312 | { |
8fb4b536 | 1313 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1314 | |
1315 | spin_lock(&gl->gl_spin); | |
1316 | ||
50299965 SW |
1317 | if (test_bit(GLF_LOCK, &gl->gl_flags) || !list_empty(&gl->gl_holders) || |
1318 | !list_empty(&gl->gl_waiters1) || !list_empty(&gl->gl_waiters2) || | |
b3b94faa DT |
1319 | !list_empty(&gl->gl_waiters3) || |
1320 | relaxed_state_ok(gl->gl_state, state, flags)) { | |
1321 | spin_unlock(&gl->gl_spin); | |
1322 | return; | |
1323 | } | |
1324 | ||
1325 | set_bit(GLF_PREFETCH, &gl->gl_flags); | |
1326 | set_bit(GLF_LOCK, &gl->gl_flags); | |
1327 | spin_unlock(&gl->gl_spin); | |
1328 | ||
1329 | glops->go_xmote_th(gl, state, flags); | |
b3b94faa DT |
1330 | } |
1331 | ||
b3b94faa DT |
1332 | static void greedy_work(void *data) |
1333 | { | |
e7f5c01c | 1334 | struct greedy *gr = data; |
b3b94faa DT |
1335 | struct gfs2_holder *gh = &gr->gr_gh; |
1336 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1337 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1338 | |
1339 | clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1340 | ||
1341 | if (glops->go_greedy) | |
1342 | glops->go_greedy(gl); | |
1343 | ||
1344 | spin_lock(&gl->gl_spin); | |
1345 | ||
1346 | if (list_empty(&gl->gl_waiters2)) { | |
1347 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1348 | spin_unlock(&gl->gl_spin); | |
1349 | gfs2_holder_uninit(gh); | |
1350 | kfree(gr); | |
1351 | } else { | |
1352 | gfs2_glock_hold(gl); | |
1353 | list_add_tail(&gh->gh_list, &gl->gl_waiters2); | |
1354 | run_queue(gl); | |
1355 | spin_unlock(&gl->gl_spin); | |
1356 | gfs2_glock_put(gl); | |
1357 | } | |
1358 | } | |
1359 | ||
1360 | /** | |
1361 | * gfs2_glock_be_greedy - | |
1362 | * @gl: | |
1363 | * @time: | |
1364 | * | |
1365 | * Returns: 0 if go_greedy will be called, 1 otherwise | |
1366 | */ | |
1367 | ||
1368 | int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time) | |
1369 | { | |
1370 | struct greedy *gr; | |
1371 | struct gfs2_holder *gh; | |
1372 | ||
feaa7bba | 1373 | if (!time || gl->gl_sbd->sd_args.ar_localcaching || |
b3b94faa DT |
1374 | test_and_set_bit(GLF_GREEDY, &gl->gl_flags)) |
1375 | return 1; | |
1376 | ||
1377 | gr = kmalloc(sizeof(struct greedy), GFP_KERNEL); | |
1378 | if (!gr) { | |
1379 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1380 | return 1; | |
1381 | } | |
1382 | gh = &gr->gr_gh; | |
1383 | ||
579b78a4 | 1384 | gfs2_holder_init(gl, 0, 0, gh); |
b3b94faa DT |
1385 | set_bit(HIF_GREEDY, &gh->gh_iflags); |
1386 | INIT_WORK(&gr->gr_work, greedy_work, gr); | |
1387 | ||
1388 | set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1389 | schedule_delayed_work(&gr->gr_work, time); | |
1390 | ||
1391 | return 0; | |
1392 | } | |
1393 | ||
b3b94faa DT |
1394 | /** |
1395 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1396 | * @gh: the holder structure | |
1397 | * | |
1398 | */ | |
1399 | ||
1400 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1401 | { | |
1402 | gfs2_glock_dq(gh); | |
1403 | gfs2_holder_uninit(gh); | |
1404 | } | |
1405 | ||
1406 | /** | |
1407 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1408 | * @sdp: the filesystem | |
1409 | * @number: the lock number | |
1410 | * @glops: the glock operations for the type of glock | |
1411 | * @state: the state to acquire the glock in | |
1412 | * @flags: modifier flags for the aquisition | |
1413 | * @gh: the struct gfs2_holder | |
1414 | * | |
1415 | * Returns: errno | |
1416 | */ | |
1417 | ||
1418 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, uint64_t number, | |
8fb4b536 SW |
1419 | const struct gfs2_glock_operations *glops, |
1420 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1421 | { |
1422 | struct gfs2_glock *gl; | |
1423 | int error; | |
1424 | ||
1425 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1426 | if (!error) { | |
1427 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1428 | gfs2_glock_put(gl); | |
1429 | } | |
1430 | ||
1431 | return error; | |
1432 | } | |
1433 | ||
1434 | /** | |
1435 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1436 | * @arg_a: the first structure | |
1437 | * @arg_b: the second structure | |
1438 | * | |
1439 | */ | |
1440 | ||
1441 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1442 | { | |
1443 | struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a; | |
1444 | struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b; | |
1445 | struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1446 | struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
1447 | int ret = 0; | |
1448 | ||
1449 | if (a->ln_number > b->ln_number) | |
1450 | ret = 1; | |
1451 | else if (a->ln_number < b->ln_number) | |
1452 | ret = -1; | |
1453 | else { | |
1454 | if (gh_a->gh_state == LM_ST_SHARED && | |
1455 | gh_b->gh_state == LM_ST_EXCLUSIVE) | |
1456 | ret = 1; | |
1457 | else if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && | |
1458 | (gh_b->gh_flags & GL_LOCAL_EXCL)) | |
1459 | ret = 1; | |
1460 | } | |
1461 | ||
1462 | return ret; | |
1463 | } | |
1464 | ||
1465 | /** | |
1466 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1467 | * @num_gh: the number of structures | |
1468 | * @ghs: an array of struct gfs2_holder structures | |
1469 | * | |
1470 | * Returns: 0 on success (all glocks acquired), | |
1471 | * errno on failure (no glocks acquired) | |
1472 | */ | |
1473 | ||
1474 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1475 | struct gfs2_holder **p) | |
1476 | { | |
1477 | unsigned int x; | |
1478 | int error = 0; | |
1479 | ||
1480 | for (x = 0; x < num_gh; x++) | |
1481 | p[x] = &ghs[x]; | |
1482 | ||
1483 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1484 | ||
1485 | for (x = 0; x < num_gh; x++) { | |
1486 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1487 | ||
1488 | error = gfs2_glock_nq(p[x]); | |
1489 | if (error) { | |
1490 | while (x--) | |
1491 | gfs2_glock_dq(p[x]); | |
1492 | break; | |
1493 | } | |
1494 | } | |
1495 | ||
1496 | return error; | |
1497 | } | |
1498 | ||
1499 | /** | |
1500 | * gfs2_glock_nq_m - acquire multiple glocks | |
1501 | * @num_gh: the number of structures | |
1502 | * @ghs: an array of struct gfs2_holder structures | |
1503 | * | |
1504 | * Figure out how big an impact this function has. Either: | |
1505 | * 1) Replace this code with code that calls gfs2_glock_prefetch() | |
1506 | * 2) Forget async stuff and just call nq_m_sync() | |
1507 | * 3) Leave it like it is | |
1508 | * | |
1509 | * Returns: 0 on success (all glocks acquired), | |
1510 | * errno on failure (no glocks acquired) | |
1511 | */ | |
1512 | ||
1513 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1514 | { | |
1515 | int *e; | |
1516 | unsigned int x; | |
1517 | int borked = 0, serious = 0; | |
1518 | int error = 0; | |
1519 | ||
1520 | if (!num_gh) | |
1521 | return 0; | |
1522 | ||
1523 | if (num_gh == 1) { | |
1524 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1525 | return gfs2_glock_nq(ghs); | |
1526 | } | |
1527 | ||
1528 | e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL); | |
1529 | if (!e) | |
1530 | return -ENOMEM; | |
1531 | ||
1532 | for (x = 0; x < num_gh; x++) { | |
1533 | ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC; | |
1534 | error = gfs2_glock_nq(&ghs[x]); | |
1535 | if (error) { | |
1536 | borked = 1; | |
1537 | serious = error; | |
1538 | num_gh = x; | |
1539 | break; | |
1540 | } | |
1541 | } | |
1542 | ||
1543 | for (x = 0; x < num_gh; x++) { | |
1544 | error = e[x] = glock_wait_internal(&ghs[x]); | |
1545 | if (error) { | |
1546 | borked = 1; | |
1547 | if (error != GLR_TRYFAILED && error != GLR_CANCELED) | |
1548 | serious = error; | |
1549 | } | |
1550 | } | |
1551 | ||
1552 | if (!borked) { | |
1553 | kfree(e); | |
1554 | return 0; | |
1555 | } | |
1556 | ||
1557 | for (x = 0; x < num_gh; x++) | |
1558 | if (!e[x]) | |
1559 | gfs2_glock_dq(&ghs[x]); | |
1560 | ||
1561 | if (serious) | |
1562 | error = serious; | |
1563 | else { | |
1564 | for (x = 0; x < num_gh; x++) | |
1565 | gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags, | |
1566 | &ghs[x]); | |
1567 | error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e); | |
1568 | } | |
1569 | ||
1570 | kfree(e); | |
1571 | ||
1572 | return error; | |
1573 | } | |
1574 | ||
1575 | /** | |
1576 | * gfs2_glock_dq_m - release multiple glocks | |
1577 | * @num_gh: the number of structures | |
1578 | * @ghs: an array of struct gfs2_holder structures | |
1579 | * | |
1580 | */ | |
1581 | ||
1582 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1583 | { | |
1584 | unsigned int x; | |
1585 | ||
1586 | for (x = 0; x < num_gh; x++) | |
1587 | gfs2_glock_dq(&ghs[x]); | |
1588 | } | |
1589 | ||
1590 | /** | |
1591 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1592 | * @num_gh: the number of structures | |
1593 | * @ghs: an array of struct gfs2_holder structures | |
1594 | * | |
1595 | */ | |
1596 | ||
1597 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1598 | { | |
1599 | unsigned int x; | |
1600 | ||
1601 | for (x = 0; x < num_gh; x++) | |
1602 | gfs2_glock_dq_uninit(&ghs[x]); | |
1603 | } | |
1604 | ||
1605 | /** | |
1606 | * gfs2_glock_prefetch_num - prefetch a glock based on lock number | |
1607 | * @sdp: the filesystem | |
1608 | * @number: the lock number | |
1609 | * @glops: the glock operations for the type of glock | |
1610 | * @state: the state to acquire the glock in | |
1611 | * @flags: modifier flags for the aquisition | |
1612 | * | |
1613 | * Returns: errno | |
1614 | */ | |
1615 | ||
1616 | void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, uint64_t number, | |
8fb4b536 | 1617 | const struct gfs2_glock_operations *glops, |
b3b94faa DT |
1618 | unsigned int state, int flags) |
1619 | { | |
1620 | struct gfs2_glock *gl; | |
1621 | int error; | |
1622 | ||
1623 | if (atomic_read(&sdp->sd_reclaim_count) < | |
1624 | gfs2_tune_get(sdp, gt_reclaim_limit)) { | |
1625 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1626 | if (!error) { | |
1627 | gfs2_glock_prefetch(gl, state, flags); | |
1628 | gfs2_glock_put(gl); | |
1629 | } | |
1630 | } | |
1631 | } | |
1632 | ||
1633 | /** | |
1634 | * gfs2_lvb_hold - attach a LVB from a glock | |
1635 | * @gl: The glock in question | |
1636 | * | |
1637 | */ | |
1638 | ||
1639 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1640 | { | |
1641 | int error; | |
1642 | ||
1643 | gfs2_glmutex_lock(gl); | |
1644 | ||
1645 | if (!atomic_read(&gl->gl_lvb_count)) { | |
1646 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
1647 | if (error) { | |
1648 | gfs2_glmutex_unlock(gl); | |
1649 | return error; | |
1650 | } | |
1651 | gfs2_glock_hold(gl); | |
1652 | } | |
1653 | atomic_inc(&gl->gl_lvb_count); | |
1654 | ||
1655 | gfs2_glmutex_unlock(gl); | |
1656 | ||
1657 | return 0; | |
1658 | } | |
1659 | ||
1660 | /** | |
1661 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1662 | * @gl: The glock in question | |
1663 | * | |
1664 | */ | |
1665 | ||
1666 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1667 | { | |
1668 | gfs2_glock_hold(gl); | |
1669 | gfs2_glmutex_lock(gl); | |
1670 | ||
1671 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); | |
1672 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
1673 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1674 | gl->gl_lvb = NULL; | |
1675 | gfs2_glock_put(gl); | |
1676 | } | |
1677 | ||
1678 | gfs2_glmutex_unlock(gl); | |
1679 | gfs2_glock_put(gl); | |
1680 | } | |
1681 | ||
b3b94faa DT |
1682 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, |
1683 | unsigned int state) | |
1684 | { | |
1685 | struct gfs2_glock *gl; | |
1686 | ||
1687 | gl = gfs2_glock_find(sdp, name); | |
1688 | if (!gl) | |
1689 | return; | |
1690 | ||
1691 | if (gl->gl_ops->go_callback) | |
1692 | gl->gl_ops->go_callback(gl, state); | |
1693 | handle_callback(gl, state); | |
1694 | ||
1695 | spin_lock(&gl->gl_spin); | |
1696 | run_queue(gl); | |
1697 | spin_unlock(&gl->gl_spin); | |
1698 | ||
1699 | gfs2_glock_put(gl); | |
1700 | } | |
1701 | ||
1702 | /** | |
1703 | * gfs2_glock_cb - Callback used by locking module | |
1704 | * @fsdata: Pointer to the superblock | |
1705 | * @type: Type of callback | |
1706 | * @data: Type dependent data pointer | |
1707 | * | |
1708 | * Called by the locking module when it wants to tell us something. | |
1709 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1710 | * a journal from another client needs to be recovered. | |
1711 | */ | |
1712 | ||
1713 | void gfs2_glock_cb(lm_fsdata_t *fsdata, unsigned int type, void *data) | |
1714 | { | |
1715 | struct gfs2_sbd *sdp = (struct gfs2_sbd *)fsdata; | |
1716 | ||
b3b94faa DT |
1717 | switch (type) { |
1718 | case LM_CB_NEED_E: | |
e7f5c01c | 1719 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
b3b94faa DT |
1720 | return; |
1721 | ||
1722 | case LM_CB_NEED_D: | |
e7f5c01c | 1723 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
b3b94faa DT |
1724 | return; |
1725 | ||
1726 | case LM_CB_NEED_S: | |
e7f5c01c | 1727 | blocking_cb(sdp, data, LM_ST_SHARED); |
b3b94faa DT |
1728 | return; |
1729 | ||
1730 | case LM_CB_ASYNC: { | |
e7f5c01c | 1731 | struct lm_async_cb *async = data; |
b3b94faa DT |
1732 | struct gfs2_glock *gl; |
1733 | ||
1734 | gl = gfs2_glock_find(sdp, &async->lc_name); | |
1735 | if (gfs2_assert_warn(sdp, gl)) | |
1736 | return; | |
1737 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) | |
1738 | gl->gl_req_bh(gl, async->lc_ret); | |
1739 | gfs2_glock_put(gl); | |
b3b94faa DT |
1740 | return; |
1741 | } | |
1742 | ||
1743 | case LM_CB_NEED_RECOVERY: | |
1744 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1745 | if (sdp->sd_recoverd_process) | |
1746 | wake_up_process(sdp->sd_recoverd_process); | |
1747 | return; | |
1748 | ||
1749 | case LM_CB_DROPLOCKS: | |
1750 | gfs2_gl_hash_clear(sdp, NO_WAIT); | |
1751 | gfs2_quota_scan(sdp); | |
1752 | return; | |
1753 | ||
1754 | default: | |
1755 | gfs2_assert_warn(sdp, 0); | |
1756 | return; | |
1757 | } | |
1758 | } | |
1759 | ||
b3b94faa DT |
1760 | /** |
1761 | * gfs2_iopen_go_callback - Try to kick the inode/vnode associated with an | |
1762 | * iopen glock from memory | |
1763 | * @io_gl: the iopen glock | |
1764 | * @state: the state into which the glock should be put | |
1765 | * | |
1766 | */ | |
1767 | ||
1768 | void gfs2_iopen_go_callback(struct gfs2_glock *io_gl, unsigned int state) | |
1769 | { | |
b3b94faa DT |
1770 | |
1771 | if (state != LM_ST_UNLOCKED) | |
1772 | return; | |
feaa7bba | 1773 | /* FIXME: remove this? */ |
b3b94faa DT |
1774 | } |
1775 | ||
1776 | /** | |
1777 | * demote_ok - Check to see if it's ok to unlock a glock | |
1778 | * @gl: the glock | |
1779 | * | |
1780 | * Returns: 1 if it's ok | |
1781 | */ | |
1782 | ||
1783 | static int demote_ok(struct gfs2_glock *gl) | |
1784 | { | |
1785 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1786 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1787 | int demote = 1; |
1788 | ||
1789 | if (test_bit(GLF_STICKY, &gl->gl_flags)) | |
1790 | demote = 0; | |
1791 | else if (test_bit(GLF_PREFETCH, &gl->gl_flags)) | |
50299965 | 1792 | demote = time_after_eq(jiffies, gl->gl_stamp + |
b3b94faa DT |
1793 | gfs2_tune_get(sdp, gt_prefetch_secs) * HZ); |
1794 | else if (glops->go_demote_ok) | |
1795 | demote = glops->go_demote_ok(gl); | |
1796 | ||
1797 | return demote; | |
1798 | } | |
1799 | ||
1800 | /** | |
1801 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
1802 | * @gl: the glock | |
1803 | * | |
1804 | */ | |
1805 | ||
1806 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
1807 | { | |
1808 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1809 | ||
1810 | spin_lock(&sdp->sd_reclaim_lock); | |
1811 | if (list_empty(&gl->gl_reclaim)) { | |
1812 | gfs2_glock_hold(gl); | |
1813 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); | |
1814 | atomic_inc(&sdp->sd_reclaim_count); | |
1815 | } | |
1816 | spin_unlock(&sdp->sd_reclaim_lock); | |
1817 | ||
1818 | wake_up(&sdp->sd_reclaim_wq); | |
1819 | } | |
1820 | ||
1821 | /** | |
1822 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list | |
1823 | * @sdp: the filesystem | |
1824 | * | |
1825 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a | |
1826 | * different glock and we notice that there are a lot of glocks in the | |
1827 | * reclaim list. | |
1828 | * | |
1829 | */ | |
1830 | ||
1831 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) | |
1832 | { | |
1833 | struct gfs2_glock *gl; | |
1834 | ||
1835 | spin_lock(&sdp->sd_reclaim_lock); | |
1836 | if (list_empty(&sdp->sd_reclaim_list)) { | |
1837 | spin_unlock(&sdp->sd_reclaim_lock); | |
1838 | return; | |
1839 | } | |
1840 | gl = list_entry(sdp->sd_reclaim_list.next, | |
1841 | struct gfs2_glock, gl_reclaim); | |
1842 | list_del_init(&gl->gl_reclaim); | |
1843 | spin_unlock(&sdp->sd_reclaim_lock); | |
1844 | ||
1845 | atomic_dec(&sdp->sd_reclaim_count); | |
1846 | atomic_inc(&sdp->sd_reclaimed); | |
1847 | ||
1848 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa | 1849 | if (queue_empty(gl, &gl->gl_holders) && |
50299965 | 1850 | gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) |
b3b94faa DT |
1851 | handle_callback(gl, LM_ST_UNLOCKED); |
1852 | gfs2_glmutex_unlock(gl); | |
1853 | } | |
1854 | ||
1855 | gfs2_glock_put(gl); | |
1856 | } | |
1857 | ||
1858 | /** | |
1859 | * examine_bucket - Call a function for glock in a hash bucket | |
1860 | * @examiner: the function | |
1861 | * @sdp: the filesystem | |
1862 | * @bucket: the bucket | |
1863 | * | |
1864 | * Returns: 1 if the bucket has entries | |
1865 | */ | |
1866 | ||
1867 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
1868 | struct gfs2_gl_hash_bucket *bucket) | |
1869 | { | |
1870 | struct glock_plug plug; | |
1871 | struct list_head *tmp; | |
1872 | struct gfs2_glock *gl; | |
1873 | int entries; | |
1874 | ||
1875 | /* Add "plug" to end of bucket list, work back up list from there */ | |
1876 | memset(&plug.gl_flags, 0, sizeof(unsigned long)); | |
1877 | set_bit(GLF_PLUG, &plug.gl_flags); | |
1878 | ||
1879 | write_lock(&bucket->hb_lock); | |
1880 | list_add(&plug.gl_list, &bucket->hb_list); | |
1881 | write_unlock(&bucket->hb_lock); | |
1882 | ||
1883 | for (;;) { | |
1884 | write_lock(&bucket->hb_lock); | |
1885 | ||
1886 | for (;;) { | |
1887 | tmp = plug.gl_list.next; | |
1888 | ||
1889 | if (tmp == &bucket->hb_list) { | |
1890 | list_del(&plug.gl_list); | |
1891 | entries = !list_empty(&bucket->hb_list); | |
1892 | write_unlock(&bucket->hb_lock); | |
1893 | return entries; | |
1894 | } | |
1895 | gl = list_entry(tmp, struct gfs2_glock, gl_list); | |
1896 | ||
1897 | /* Move plug up list */ | |
1898 | list_move(&plug.gl_list, &gl->gl_list); | |
1899 | ||
1900 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
1901 | continue; | |
1902 | ||
1903 | /* examiner() must glock_put() */ | |
1904 | gfs2_glock_hold(gl); | |
1905 | ||
1906 | break; | |
1907 | } | |
1908 | ||
1909 | write_unlock(&bucket->hb_lock); | |
1910 | ||
1911 | examiner(gl); | |
1912 | } | |
1913 | } | |
1914 | ||
1915 | /** | |
1916 | * scan_glock - look at a glock and see if we can reclaim it | |
1917 | * @gl: the glock to look at | |
1918 | * | |
1919 | */ | |
1920 | ||
1921 | static void scan_glock(struct gfs2_glock *gl) | |
1922 | { | |
a2242db0 SW |
1923 | if (gl->gl_ops == &gfs2_inode_glops) |
1924 | goto out; | |
1925 | ||
b3b94faa | 1926 | if (gfs2_glmutex_trylock(gl)) { |
b3b94faa DT |
1927 | if (queue_empty(gl, &gl->gl_holders) && |
1928 | gl->gl_state != LM_ST_UNLOCKED && | |
1929 | demote_ok(gl)) | |
1930 | goto out_schedule; | |
b3b94faa DT |
1931 | gfs2_glmutex_unlock(gl); |
1932 | } | |
a2242db0 | 1933 | out: |
b3b94faa | 1934 | gfs2_glock_put(gl); |
b3b94faa DT |
1935 | return; |
1936 | ||
627add2d | 1937 | out_schedule: |
b3b94faa DT |
1938 | gfs2_glmutex_unlock(gl); |
1939 | gfs2_glock_schedule_for_reclaim(gl); | |
1940 | gfs2_glock_put(gl); | |
1941 | } | |
1942 | ||
1943 | /** | |
1944 | * gfs2_scand_internal - Look for glocks and inodes to toss from memory | |
1945 | * @sdp: the filesystem | |
1946 | * | |
1947 | */ | |
1948 | ||
1949 | void gfs2_scand_internal(struct gfs2_sbd *sdp) | |
1950 | { | |
1951 | unsigned int x; | |
1952 | ||
1953 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
1954 | examine_bucket(scan_glock, sdp, &sdp->sd_gl_hash[x]); | |
1955 | cond_resched(); | |
1956 | } | |
1957 | } | |
1958 | ||
1959 | /** | |
1960 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1961 | * @gl: the glock to look at | |
1962 | * | |
1963 | */ | |
1964 | ||
1965 | static void clear_glock(struct gfs2_glock *gl) | |
1966 | { | |
1967 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1968 | int released; | |
1969 | ||
1970 | spin_lock(&sdp->sd_reclaim_lock); | |
1971 | if (!list_empty(&gl->gl_reclaim)) { | |
1972 | list_del_init(&gl->gl_reclaim); | |
1973 | atomic_dec(&sdp->sd_reclaim_count); | |
190562bd | 1974 | spin_unlock(&sdp->sd_reclaim_lock); |
b3b94faa DT |
1975 | released = gfs2_glock_put(gl); |
1976 | gfs2_assert(sdp, !released); | |
190562bd SW |
1977 | } else { |
1978 | spin_unlock(&sdp->sd_reclaim_lock); | |
b3b94faa | 1979 | } |
b3b94faa DT |
1980 | |
1981 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa DT |
1982 | if (queue_empty(gl, &gl->gl_holders) && |
1983 | gl->gl_state != LM_ST_UNLOCKED) | |
1984 | handle_callback(gl, LM_ST_UNLOCKED); | |
1985 | ||
1986 | gfs2_glmutex_unlock(gl); | |
1987 | } | |
1988 | ||
1989 | gfs2_glock_put(gl); | |
1990 | } | |
1991 | ||
1992 | /** | |
1993 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1994 | * @sdp: the filesystem | |
1995 | * @wait: wait until it's all gone | |
1996 | * | |
1997 | * Called when unmounting the filesystem, or when inter-node lock manager | |
1998 | * requests DROPLOCKS because it is running out of capacity. | |
1999 | */ | |
2000 | ||
2001 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) | |
2002 | { | |
2003 | unsigned long t; | |
2004 | unsigned int x; | |
2005 | int cont; | |
2006 | ||
2007 | t = jiffies; | |
2008 | ||
2009 | for (;;) { | |
2010 | cont = 0; | |
2011 | ||
2012 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
50299965 | 2013 | if (examine_bucket(clear_glock, sdp, &sdp->sd_gl_hash[x])) |
b3b94faa DT |
2014 | cont = 1; |
2015 | ||
2016 | if (!wait || !cont) | |
2017 | break; | |
2018 | ||
2019 | if (time_after_eq(jiffies, | |
2020 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
2021 | fs_warn(sdp, "Unmount seems to be stalled. " | |
2022 | "Dumping lock state...\n"); | |
2023 | gfs2_dump_lockstate(sdp); | |
2024 | t = jiffies; | |
2025 | } | |
2026 | ||
b3b94faa | 2027 | invalidate_inodes(sdp->sd_vfs); |
fd88de56 | 2028 | msleep(10); |
b3b94faa DT |
2029 | } |
2030 | } | |
2031 | ||
2032 | /* | |
2033 | * Diagnostic routines to help debug distributed deadlock | |
2034 | */ | |
2035 | ||
2036 | /** | |
2037 | * dump_holder - print information about a glock holder | |
2038 | * @str: a string naming the type of holder | |
2039 | * @gh: the glock holder | |
2040 | * | |
2041 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2042 | */ | |
2043 | ||
2044 | static int dump_holder(char *str, struct gfs2_holder *gh) | |
2045 | { | |
2046 | unsigned int x; | |
2047 | int error = -ENOBUFS; | |
2048 | ||
d92a8d48 SW |
2049 | printk(KERN_INFO " %s\n", str); |
2050 | printk(KERN_INFO " owner = %ld\n", | |
b3b94faa | 2051 | (gh->gh_owner) ? (long)gh->gh_owner->pid : -1); |
d92a8d48 SW |
2052 | printk(KERN_INFO " gh_state = %u\n", gh->gh_state); |
2053 | printk(KERN_INFO " gh_flags ="); | |
b3b94faa DT |
2054 | for (x = 0; x < 32; x++) |
2055 | if (gh->gh_flags & (1 << x)) | |
2056 | printk(" %u", x); | |
2057 | printk(" \n"); | |
d92a8d48 SW |
2058 | printk(KERN_INFO " error = %d\n", gh->gh_error); |
2059 | printk(KERN_INFO " gh_iflags ="); | |
b3b94faa DT |
2060 | for (x = 0; x < 32; x++) |
2061 | if (test_bit(x, &gh->gh_iflags)) | |
2062 | printk(" %u", x); | |
2063 | printk(" \n"); | |
d0dc80db | 2064 | print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip); |
b3b94faa DT |
2065 | |
2066 | error = 0; | |
2067 | ||
2068 | return error; | |
2069 | } | |
2070 | ||
2071 | /** | |
2072 | * dump_inode - print information about an inode | |
2073 | * @ip: the inode | |
2074 | * | |
2075 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2076 | */ | |
2077 | ||
2078 | static int dump_inode(struct gfs2_inode *ip) | |
2079 | { | |
2080 | unsigned int x; | |
2081 | int error = -ENOBUFS; | |
2082 | ||
d92a8d48 SW |
2083 | printk(KERN_INFO " Inode:\n"); |
2084 | printk(KERN_INFO " num = %llu %llu\n", | |
382066da SW |
2085 | (unsigned long long)ip->i_num.no_formal_ino, |
2086 | (unsigned long long)ip->i_num.no_addr); | |
d92a8d48 | 2087 | printk(KERN_INFO " type = %u\n", IF2DT(ip->i_di.di_mode)); |
d92a8d48 | 2088 | printk(KERN_INFO " i_flags ="); |
b3b94faa DT |
2089 | for (x = 0; x < 32; x++) |
2090 | if (test_bit(x, &ip->i_flags)) | |
2091 | printk(" %u", x); | |
2092 | printk(" \n"); | |
b3b94faa DT |
2093 | |
2094 | error = 0; | |
2095 | ||
2096 | return error; | |
2097 | } | |
2098 | ||
2099 | /** | |
2100 | * dump_glock - print information about a glock | |
2101 | * @gl: the glock | |
2102 | * @count: where we are in the buffer | |
2103 | * | |
2104 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2105 | */ | |
2106 | ||
2107 | static int dump_glock(struct gfs2_glock *gl) | |
2108 | { | |
2109 | struct gfs2_holder *gh; | |
2110 | unsigned int x; | |
2111 | int error = -ENOBUFS; | |
2112 | ||
2113 | spin_lock(&gl->gl_spin); | |
2114 | ||
88721877 RC |
2115 | printk(KERN_INFO "Glock 0x%p (%u, %llu)\n", |
2116 | gl, | |
2117 | gl->gl_name.ln_type, | |
382066da | 2118 | (unsigned long long)gl->gl_name.ln_number); |
d92a8d48 | 2119 | printk(KERN_INFO " gl_flags ="); |
b3b94faa DT |
2120 | for (x = 0; x < 32; x++) |
2121 | if (test_bit(x, &gl->gl_flags)) | |
2122 | printk(" %u", x); | |
2123 | printk(" \n"); | |
d92a8d48 SW |
2124 | printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref.refcount)); |
2125 | printk(KERN_INFO " gl_state = %u\n", gl->gl_state); | |
320dd101 SW |
2126 | printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm); |
2127 | print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip); | |
d92a8d48 SW |
2128 | printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); |
2129 | printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); | |
2130 | printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); | |
2131 | printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no"); | |
2132 | printk(KERN_INFO " le = %s\n", | |
b3b94faa | 2133 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
d92a8d48 | 2134 | printk(KERN_INFO " reclaim = %s\n", |
b3b94faa DT |
2135 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); |
2136 | if (gl->gl_aspace) | |
88721877 RC |
2137 | printk(KERN_INFO " aspace = 0x%p nrpages = %lu\n", |
2138 | gl->gl_aspace, | |
2139 | gl->gl_aspace->i_mapping->nrpages); | |
b3b94faa | 2140 | else |
d92a8d48 SW |
2141 | printk(KERN_INFO " aspace = no\n"); |
2142 | printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count)); | |
b3b94faa DT |
2143 | if (gl->gl_req_gh) { |
2144 | error = dump_holder("Request", gl->gl_req_gh); | |
2145 | if (error) | |
2146 | goto out; | |
2147 | } | |
2148 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
2149 | error = dump_holder("Holder", gh); | |
2150 | if (error) | |
2151 | goto out; | |
2152 | } | |
2153 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { | |
2154 | error = dump_holder("Waiter1", gh); | |
2155 | if (error) | |
2156 | goto out; | |
2157 | } | |
2158 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
2159 | error = dump_holder("Waiter2", gh); | |
2160 | if (error) | |
2161 | goto out; | |
2162 | } | |
2163 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { | |
2164 | error = dump_holder("Waiter3", gh); | |
2165 | if (error) | |
2166 | goto out; | |
2167 | } | |
5c676f6d | 2168 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { |
b3b94faa DT |
2169 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && |
2170 | list_empty(&gl->gl_holders)) { | |
5c676f6d | 2171 | error = dump_inode(gl->gl_object); |
b3b94faa DT |
2172 | if (error) |
2173 | goto out; | |
2174 | } else { | |
2175 | error = -ENOBUFS; | |
d92a8d48 | 2176 | printk(KERN_INFO " Inode: busy\n"); |
b3b94faa DT |
2177 | } |
2178 | } | |
2179 | ||
2180 | error = 0; | |
2181 | ||
2182 | out: | |
2183 | spin_unlock(&gl->gl_spin); | |
2184 | ||
2185 | return error; | |
2186 | } | |
2187 | ||
2188 | /** | |
2189 | * gfs2_dump_lockstate - print out the current lockstate | |
2190 | * @sdp: the filesystem | |
2191 | * @ub: the buffer to copy the information into | |
2192 | * | |
2193 | * If @ub is NULL, dump the lockstate to the console. | |
2194 | * | |
2195 | */ | |
2196 | ||
08bc2dbc | 2197 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
b3b94faa DT |
2198 | { |
2199 | struct gfs2_gl_hash_bucket *bucket; | |
2200 | struct gfs2_glock *gl; | |
2201 | unsigned int x; | |
2202 | int error = 0; | |
2203 | ||
2204 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2205 | bucket = &sdp->sd_gl_hash[x]; | |
2206 | ||
2207 | read_lock(&bucket->hb_lock); | |
2208 | ||
2209 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
2210 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
2211 | continue; | |
2212 | ||
2213 | error = dump_glock(gl); | |
2214 | if (error) | |
2215 | break; | |
2216 | } | |
2217 | ||
2218 | read_unlock(&bucket->hb_lock); | |
2219 | ||
2220 | if (error) | |
2221 | break; | |
2222 | } | |
2223 | ||
2224 | ||
2225 | return error; | |
2226 | } | |
2227 |