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. */ | |
303 | if (glops == &gfs2_inode_glops || | |
f45b7ddd | 304 | glops == &gfs2_rgrp_glops) { |
b3b94faa DT |
305 | gl->gl_aspace = gfs2_aspace_get(sdp); |
306 | if (!gl->gl_aspace) { | |
307 | error = -ENOMEM; | |
308 | goto fail; | |
309 | } | |
310 | } | |
311 | ||
312 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
313 | if (error) | |
314 | goto fail_aspace; | |
315 | ||
b3b94faa | 316 | write_lock(&bucket->hb_lock); |
899be4d3 | 317 | tmp = search_bucket(bucket, sdp, &name); |
b3b94faa DT |
318 | if (tmp) { |
319 | write_unlock(&bucket->hb_lock); | |
320 | glock_free(gl); | |
321 | gl = tmp; | |
322 | } else { | |
323 | list_add_tail(&gl->gl_list, &bucket->hb_list); | |
324 | write_unlock(&bucket->hb_lock); | |
325 | } | |
326 | ||
327 | *glp = gl; | |
328 | ||
329 | return 0; | |
330 | ||
ec45d9f5 | 331 | fail_aspace: |
b3b94faa DT |
332 | if (gl->gl_aspace) |
333 | gfs2_aspace_put(gl->gl_aspace); | |
ec45d9f5 | 334 | fail: |
b3b94faa | 335 | kmem_cache_free(gfs2_glock_cachep, gl); |
b3b94faa DT |
336 | return error; |
337 | } | |
338 | ||
339 | /** | |
340 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
341 | * @gl: the glock | |
342 | * @state: the state we're requesting | |
343 | * @flags: the modifier flags | |
344 | * @gh: the holder structure | |
345 | * | |
346 | */ | |
347 | ||
190562bd | 348 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
349 | struct gfs2_holder *gh) |
350 | { | |
351 | INIT_LIST_HEAD(&gh->gh_list); | |
352 | gh->gh_gl = gl; | |
d0dc80db | 353 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
190562bd | 354 | gh->gh_owner = current; |
b3b94faa DT |
355 | gh->gh_state = state; |
356 | gh->gh_flags = flags; | |
357 | gh->gh_error = 0; | |
358 | gh->gh_iflags = 0; | |
359 | init_completion(&gh->gh_wait); | |
360 | ||
361 | if (gh->gh_state == LM_ST_EXCLUSIVE) | |
362 | gh->gh_flags |= GL_LOCAL_EXCL; | |
363 | ||
364 | gfs2_glock_hold(gl); | |
365 | } | |
366 | ||
367 | /** | |
368 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
369 | * @state: the state we're requesting | |
370 | * @flags: the modifier flags | |
371 | * @gh: the holder structure | |
372 | * | |
373 | * Don't mess with the glock. | |
374 | * | |
375 | */ | |
376 | ||
190562bd | 377 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
378 | { |
379 | gh->gh_state = state; | |
579b78a4 | 380 | gh->gh_flags = flags; |
b3b94faa DT |
381 | if (gh->gh_state == LM_ST_EXCLUSIVE) |
382 | gh->gh_flags |= GL_LOCAL_EXCL; | |
383 | ||
384 | gh->gh_iflags &= 1 << HIF_ALLOCED; | |
d0dc80db | 385 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
386 | } |
387 | ||
388 | /** | |
389 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
390 | * @gh: the holder structure | |
391 | * | |
392 | */ | |
393 | ||
394 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
395 | { | |
396 | gfs2_glock_put(gh->gh_gl); | |
397 | gh->gh_gl = NULL; | |
d0dc80db | 398 | gh->gh_ip = 0; |
b3b94faa DT |
399 | } |
400 | ||
401 | /** | |
402 | * gfs2_holder_get - get a struct gfs2_holder structure | |
403 | * @gl: the glock | |
404 | * @state: the state we're requesting | |
405 | * @flags: the modifier flags | |
af18ddb8 | 406 | * @gfp_flags: |
b3b94faa DT |
407 | * |
408 | * Figure out how big an impact this function has. Either: | |
409 | * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd | |
410 | * 2) Leave it like it is | |
411 | * | |
412 | * Returns: the holder structure, NULL on ENOMEM | |
413 | */ | |
414 | ||
08bc2dbc AB |
415 | static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, |
416 | unsigned int state, | |
417 | int flags, gfp_t gfp_flags) | |
b3b94faa DT |
418 | { |
419 | struct gfs2_holder *gh; | |
420 | ||
421 | gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags); | |
422 | if (!gh) | |
423 | return NULL; | |
424 | ||
425 | gfs2_holder_init(gl, state, flags, gh); | |
426 | set_bit(HIF_ALLOCED, &gh->gh_iflags); | |
d0dc80db | 427 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
428 | return gh; |
429 | } | |
430 | ||
431 | /** | |
432 | * gfs2_holder_put - get rid of a struct gfs2_holder structure | |
433 | * @gh: the holder structure | |
434 | * | |
435 | */ | |
436 | ||
08bc2dbc | 437 | static void gfs2_holder_put(struct gfs2_holder *gh) |
b3b94faa DT |
438 | { |
439 | gfs2_holder_uninit(gh); | |
440 | kfree(gh); | |
441 | } | |
442 | ||
b3b94faa DT |
443 | /** |
444 | * rq_mutex - process a mutex request in the queue | |
445 | * @gh: the glock holder | |
446 | * | |
447 | * Returns: 1 if the queue is blocked | |
448 | */ | |
449 | ||
450 | static int rq_mutex(struct gfs2_holder *gh) | |
451 | { | |
452 | struct gfs2_glock *gl = gh->gh_gl; | |
453 | ||
454 | list_del_init(&gh->gh_list); | |
455 | /* gh->gh_error never examined. */ | |
456 | set_bit(GLF_LOCK, &gl->gl_flags); | |
457 | complete(&gh->gh_wait); | |
458 | ||
459 | return 1; | |
460 | } | |
461 | ||
462 | /** | |
463 | * rq_promote - process a promote request in the queue | |
464 | * @gh: the glock holder | |
465 | * | |
466 | * Acquire a new inter-node lock, or change a lock state to more restrictive. | |
467 | * | |
468 | * Returns: 1 if the queue is blocked | |
469 | */ | |
470 | ||
471 | static int rq_promote(struct gfs2_holder *gh) | |
472 | { | |
473 | struct gfs2_glock *gl = gh->gh_gl; | |
474 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 475 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
476 | |
477 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
478 | if (list_empty(&gl->gl_holders)) { | |
479 | gl->gl_req_gh = gh; | |
480 | set_bit(GLF_LOCK, &gl->gl_flags); | |
481 | spin_unlock(&gl->gl_spin); | |
482 | ||
483 | if (atomic_read(&sdp->sd_reclaim_count) > | |
484 | gfs2_tune_get(sdp, gt_reclaim_limit) && | |
485 | !(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
486 | gfs2_reclaim_glock(sdp); | |
487 | gfs2_reclaim_glock(sdp); | |
488 | } | |
489 | ||
ec45d9f5 | 490 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); |
b3b94faa DT |
491 | spin_lock(&gl->gl_spin); |
492 | } | |
493 | return 1; | |
494 | } | |
495 | ||
496 | if (list_empty(&gl->gl_holders)) { | |
497 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
498 | set_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
499 | } else { |
500 | struct gfs2_holder *next_gh; | |
501 | if (gh->gh_flags & GL_LOCAL_EXCL) | |
502 | return 1; | |
503 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, | |
504 | gh_list); | |
505 | if (next_gh->gh_flags & GL_LOCAL_EXCL) | |
506 | return 1; | |
b3b94faa DT |
507 | } |
508 | ||
509 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
510 | gh->gh_error = 0; | |
511 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
512 | ||
b3b94faa DT |
513 | complete(&gh->gh_wait); |
514 | ||
515 | return 0; | |
516 | } | |
517 | ||
518 | /** | |
519 | * rq_demote - process a demote request in the queue | |
520 | * @gh: the glock holder | |
521 | * | |
522 | * Returns: 1 if the queue is blocked | |
523 | */ | |
524 | ||
525 | static int rq_demote(struct gfs2_holder *gh) | |
526 | { | |
527 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 528 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
529 | |
530 | if (!list_empty(&gl->gl_holders)) | |
531 | return 1; | |
532 | ||
533 | if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { | |
534 | list_del_init(&gh->gh_list); | |
535 | gh->gh_error = 0; | |
536 | spin_unlock(&gl->gl_spin); | |
537 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
538 | gfs2_holder_put(gh); | |
539 | else | |
540 | complete(&gh->gh_wait); | |
541 | spin_lock(&gl->gl_spin); | |
542 | } else { | |
543 | gl->gl_req_gh = gh; | |
544 | set_bit(GLF_LOCK, &gl->gl_flags); | |
545 | spin_unlock(&gl->gl_spin); | |
546 | ||
547 | if (gh->gh_state == LM_ST_UNLOCKED || | |
548 | gl->gl_state != LM_ST_EXCLUSIVE) | |
549 | glops->go_drop_th(gl); | |
550 | else | |
551 | glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags); | |
552 | ||
553 | spin_lock(&gl->gl_spin); | |
554 | } | |
555 | ||
556 | return 0; | |
557 | } | |
558 | ||
559 | /** | |
560 | * rq_greedy - process a queued request to drop greedy status | |
561 | * @gh: the glock holder | |
562 | * | |
563 | * Returns: 1 if the queue is blocked | |
564 | */ | |
565 | ||
566 | static int rq_greedy(struct gfs2_holder *gh) | |
567 | { | |
568 | struct gfs2_glock *gl = gh->gh_gl; | |
569 | ||
570 | list_del_init(&gh->gh_list); | |
571 | /* gh->gh_error never examined. */ | |
572 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
573 | spin_unlock(&gl->gl_spin); | |
574 | ||
575 | gfs2_holder_uninit(gh); | |
576 | kfree(container_of(gh, struct greedy, gr_gh)); | |
577 | ||
578 | spin_lock(&gl->gl_spin); | |
579 | ||
580 | return 0; | |
581 | } | |
582 | ||
583 | /** | |
584 | * run_queue - process holder structures on a glock | |
585 | * @gl: the glock | |
586 | * | |
587 | */ | |
b3b94faa DT |
588 | static void run_queue(struct gfs2_glock *gl) |
589 | { | |
590 | struct gfs2_holder *gh; | |
591 | int blocked = 1; | |
592 | ||
593 | for (;;) { | |
594 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
595 | break; | |
596 | ||
597 | if (!list_empty(&gl->gl_waiters1)) { | |
598 | gh = list_entry(gl->gl_waiters1.next, | |
599 | struct gfs2_holder, gh_list); | |
600 | ||
601 | if (test_bit(HIF_MUTEX, &gh->gh_iflags)) | |
602 | blocked = rq_mutex(gh); | |
603 | else | |
604 | gfs2_assert_warn(gl->gl_sbd, 0); | |
605 | ||
606 | } else if (!list_empty(&gl->gl_waiters2) && | |
607 | !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { | |
608 | gh = list_entry(gl->gl_waiters2.next, | |
609 | struct gfs2_holder, gh_list); | |
610 | ||
611 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) | |
612 | blocked = rq_demote(gh); | |
613 | else if (test_bit(HIF_GREEDY, &gh->gh_iflags)) | |
614 | blocked = rq_greedy(gh); | |
615 | else | |
616 | gfs2_assert_warn(gl->gl_sbd, 0); | |
617 | ||
618 | } else if (!list_empty(&gl->gl_waiters3)) { | |
619 | gh = list_entry(gl->gl_waiters3.next, | |
620 | struct gfs2_holder, gh_list); | |
621 | ||
622 | if (test_bit(HIF_PROMOTE, &gh->gh_iflags)) | |
623 | blocked = rq_promote(gh); | |
624 | else | |
625 | gfs2_assert_warn(gl->gl_sbd, 0); | |
626 | ||
627 | } else | |
628 | break; | |
629 | ||
630 | if (blocked) | |
631 | break; | |
632 | } | |
633 | } | |
634 | ||
635 | /** | |
636 | * gfs2_glmutex_lock - acquire a local lock on a glock | |
637 | * @gl: the glock | |
638 | * | |
639 | * Gives caller exclusive access to manipulate a glock structure. | |
640 | */ | |
641 | ||
feaa7bba | 642 | static void gfs2_glmutex_lock(struct gfs2_glock *gl) |
b3b94faa DT |
643 | { |
644 | struct gfs2_holder gh; | |
645 | ||
646 | gfs2_holder_init(gl, 0, 0, &gh); | |
647 | set_bit(HIF_MUTEX, &gh.gh_iflags); | |
648 | ||
649 | spin_lock(&gl->gl_spin); | |
650 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
651 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); | |
320dd101 SW |
652 | else { |
653 | gl->gl_owner = current; | |
654 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
b3b94faa | 655 | complete(&gh.gh_wait); |
320dd101 | 656 | } |
b3b94faa DT |
657 | spin_unlock(&gl->gl_spin); |
658 | ||
659 | wait_for_completion(&gh.gh_wait); | |
660 | gfs2_holder_uninit(&gh); | |
661 | } | |
662 | ||
663 | /** | |
664 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock | |
665 | * @gl: the glock | |
666 | * | |
667 | * Returns: 1 if the glock is acquired | |
668 | */ | |
669 | ||
08bc2dbc | 670 | static int gfs2_glmutex_trylock(struct gfs2_glock *gl) |
b3b94faa DT |
671 | { |
672 | int acquired = 1; | |
673 | ||
674 | spin_lock(&gl->gl_spin); | |
675 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
676 | acquired = 0; | |
320dd101 SW |
677 | else { |
678 | gl->gl_owner = current; | |
679 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
680 | } | |
b3b94faa DT |
681 | spin_unlock(&gl->gl_spin); |
682 | ||
683 | return acquired; | |
684 | } | |
685 | ||
686 | /** | |
687 | * gfs2_glmutex_unlock - release a local lock on a glock | |
688 | * @gl: the glock | |
689 | * | |
690 | */ | |
691 | ||
feaa7bba | 692 | static void gfs2_glmutex_unlock(struct gfs2_glock *gl) |
b3b94faa DT |
693 | { |
694 | spin_lock(&gl->gl_spin); | |
695 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
320dd101 SW |
696 | gl->gl_owner = NULL; |
697 | gl->gl_ip = 0; | |
b3b94faa | 698 | run_queue(gl); |
190562bd | 699 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
700 | spin_unlock(&gl->gl_spin); |
701 | } | |
702 | ||
703 | /** | |
704 | * handle_callback - add a demote request to a lock's queue | |
705 | * @gl: the glock | |
706 | * @state: the state the caller wants us to change to | |
707 | * | |
af18ddb8 | 708 | * Note: This may fail sliently if we are out of memory. |
b3b94faa DT |
709 | */ |
710 | ||
711 | static void handle_callback(struct gfs2_glock *gl, unsigned int state) | |
712 | { | |
713 | struct gfs2_holder *gh, *new_gh = NULL; | |
714 | ||
feaa7bba | 715 | restart: |
b3b94faa DT |
716 | spin_lock(&gl->gl_spin); |
717 | ||
718 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
719 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && | |
720 | gl->gl_req_gh != gh) { | |
721 | if (gh->gh_state != state) | |
722 | gh->gh_state = LM_ST_UNLOCKED; | |
723 | goto out; | |
724 | } | |
725 | } | |
726 | ||
727 | if (new_gh) { | |
728 | list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); | |
729 | new_gh = NULL; | |
730 | } else { | |
731 | spin_unlock(&gl->gl_spin); | |
732 | ||
af18ddb8 SW |
733 | new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_KERNEL); |
734 | if (!new_gh) | |
735 | return; | |
b3b94faa DT |
736 | set_bit(HIF_DEMOTE, &new_gh->gh_iflags); |
737 | set_bit(HIF_DEALLOC, &new_gh->gh_iflags); | |
738 | ||
739 | goto restart; | |
740 | } | |
741 | ||
feaa7bba | 742 | out: |
b3b94faa DT |
743 | spin_unlock(&gl->gl_spin); |
744 | ||
745 | if (new_gh) | |
746 | gfs2_holder_put(new_gh); | |
747 | } | |
748 | ||
feaa7bba SW |
749 | void gfs2_glock_inode_squish(struct inode *inode) |
750 | { | |
751 | struct gfs2_holder gh; | |
752 | struct gfs2_glock *gl = GFS2_I(inode)->i_gl; | |
753 | gfs2_holder_init(gl, LM_ST_UNLOCKED, 0, &gh); | |
754 | set_bit(HIF_DEMOTE, &gh.gh_iflags); | |
755 | spin_lock(&gl->gl_spin); | |
756 | gfs2_assert(inode->i_sb->s_fs_info, list_empty(&gl->gl_holders)); | |
757 | list_add_tail(&gh.gh_list, &gl->gl_waiters2); | |
758 | run_queue(gl); | |
759 | spin_unlock(&gl->gl_spin); | |
5dd9feaf | 760 | wait_for_completion(&gh.gh_wait); |
feaa7bba SW |
761 | gfs2_holder_uninit(&gh); |
762 | } | |
763 | ||
b3b94faa DT |
764 | /** |
765 | * state_change - record that the glock is now in a different state | |
766 | * @gl: the glock | |
767 | * @new_state the new state | |
768 | * | |
769 | */ | |
770 | ||
771 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
772 | { | |
b3b94faa DT |
773 | int held1, held2; |
774 | ||
775 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
776 | held2 = (new_state != LM_ST_UNLOCKED); | |
777 | ||
778 | if (held1 != held2) { | |
6a6b3d01 | 779 | if (held2) |
b3b94faa | 780 | gfs2_glock_hold(gl); |
6a6b3d01 | 781 | else |
b3b94faa | 782 | gfs2_glock_put(gl); |
b3b94faa DT |
783 | } |
784 | ||
785 | gl->gl_state = new_state; | |
786 | } | |
787 | ||
788 | /** | |
789 | * xmote_bh - Called after the lock module is done acquiring a lock | |
790 | * @gl: The glock in question | |
791 | * @ret: the int returned from the lock module | |
792 | * | |
793 | */ | |
794 | ||
795 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) | |
796 | { | |
797 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 798 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
799 | struct gfs2_holder *gh = gl->gl_req_gh; |
800 | int prev_state = gl->gl_state; | |
801 | int op_done = 1; | |
802 | ||
803 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
804 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
805 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); | |
806 | ||
807 | state_change(gl, ret & LM_OUT_ST_MASK); | |
808 | ||
809 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { | |
810 | if (glops->go_inval) | |
811 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
812 | } else if (gl->gl_state == LM_ST_DEFERRED) { | |
813 | /* We might not want to do this here. | |
814 | Look at moving to the inode glops. */ | |
815 | if (glops->go_inval) | |
816 | glops->go_inval(gl, DIO_DATA); | |
817 | } | |
818 | ||
819 | /* Deal with each possible exit condition */ | |
820 | ||
821 | if (!gh) | |
822 | gl->gl_stamp = jiffies; | |
823 | ||
824 | else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { | |
825 | spin_lock(&gl->gl_spin); | |
826 | list_del_init(&gh->gh_list); | |
827 | gh->gh_error = -EIO; | |
b3b94faa DT |
828 | spin_unlock(&gl->gl_spin); |
829 | ||
830 | } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { | |
831 | spin_lock(&gl->gl_spin); | |
832 | list_del_init(&gh->gh_list); | |
833 | if (gl->gl_state == gh->gh_state || | |
834 | gl->gl_state == LM_ST_UNLOCKED) | |
835 | gh->gh_error = 0; | |
836 | else { | |
837 | if (gfs2_assert_warn(sdp, gh->gh_flags & | |
838 | (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) | |
839 | fs_warn(sdp, "ret = 0x%.8X\n", ret); | |
840 | gh->gh_error = GLR_TRYFAILED; | |
841 | } | |
842 | spin_unlock(&gl->gl_spin); | |
843 | ||
844 | if (ret & LM_OUT_CANCELED) | |
845 | handle_callback(gl, LM_ST_UNLOCKED); /* Lame */ | |
846 | ||
847 | } else if (ret & LM_OUT_CANCELED) { | |
848 | spin_lock(&gl->gl_spin); | |
849 | list_del_init(&gh->gh_list); | |
850 | gh->gh_error = GLR_CANCELED; | |
b3b94faa DT |
851 | spin_unlock(&gl->gl_spin); |
852 | ||
853 | } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
854 | spin_lock(&gl->gl_spin); | |
855 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
856 | gh->gh_error = 0; | |
857 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
858 | spin_unlock(&gl->gl_spin); | |
859 | ||
860 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
861 | ||
862 | op_done = 0; | |
863 | ||
864 | } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
865 | spin_lock(&gl->gl_spin); | |
866 | list_del_init(&gh->gh_list); | |
867 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
868 | spin_unlock(&gl->gl_spin); |
869 | ||
870 | } else { | |
871 | if (gfs2_assert_withdraw(sdp, 0) == -1) | |
872 | fs_err(sdp, "ret = 0x%.8X\n", ret); | |
873 | } | |
874 | ||
875 | if (glops->go_xmote_bh) | |
876 | glops->go_xmote_bh(gl); | |
877 | ||
878 | if (op_done) { | |
879 | spin_lock(&gl->gl_spin); | |
880 | gl->gl_req_gh = NULL; | |
881 | gl->gl_req_bh = NULL; | |
882 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
883 | run_queue(gl); | |
884 | spin_unlock(&gl->gl_spin); | |
885 | } | |
886 | ||
887 | gfs2_glock_put(gl); | |
888 | ||
889 | if (gh) { | |
890 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
891 | gfs2_holder_put(gh); | |
892 | else | |
893 | complete(&gh->gh_wait); | |
894 | } | |
895 | } | |
896 | ||
897 | /** | |
898 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock | |
899 | * @gl: The glock in question | |
900 | * @state: the requested state | |
901 | * @flags: modifier flags to the lock call | |
902 | * | |
903 | */ | |
904 | ||
905 | void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags) | |
906 | { | |
907 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 908 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
909 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | |
910 | LM_FLAG_NOEXP | LM_FLAG_ANY | | |
911 | LM_FLAG_PRIORITY); | |
912 | unsigned int lck_ret; | |
913 | ||
914 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
915 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
916 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); | |
917 | gfs2_assert_warn(sdp, state != gl->gl_state); | |
918 | ||
919 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
920 | if (glops->go_sync) | |
921 | glops->go_sync(gl, | |
922 | DIO_METADATA | DIO_DATA | DIO_RELEASE); | |
923 | } | |
924 | ||
925 | gfs2_glock_hold(gl); | |
926 | gl->gl_req_bh = xmote_bh; | |
927 | ||
ec45d9f5 | 928 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags); |
b3b94faa DT |
929 | |
930 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) | |
931 | return; | |
932 | ||
933 | if (lck_ret & LM_OUT_ASYNC) | |
934 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); | |
935 | else | |
936 | xmote_bh(gl, lck_ret); | |
937 | } | |
938 | ||
939 | /** | |
940 | * drop_bh - Called after a lock module unlock completes | |
941 | * @gl: the glock | |
942 | * @ret: the return status | |
943 | * | |
944 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) | |
945 | * Doesn't drop the reference on the glock the top half took out | |
946 | * | |
947 | */ | |
948 | ||
949 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) | |
950 | { | |
951 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 952 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
953 | struct gfs2_holder *gh = gl->gl_req_gh; |
954 | ||
955 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
956 | ||
957 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
958 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
959 | gfs2_assert_warn(sdp, !ret); | |
960 | ||
961 | state_change(gl, LM_ST_UNLOCKED); | |
962 | ||
963 | if (glops->go_inval) | |
964 | glops->go_inval(gl, DIO_METADATA | DIO_DATA); | |
965 | ||
966 | if (gh) { | |
967 | spin_lock(&gl->gl_spin); | |
968 | list_del_init(&gh->gh_list); | |
969 | gh->gh_error = 0; | |
970 | spin_unlock(&gl->gl_spin); | |
971 | } | |
972 | ||
973 | if (glops->go_drop_bh) | |
974 | glops->go_drop_bh(gl); | |
975 | ||
976 | spin_lock(&gl->gl_spin); | |
977 | gl->gl_req_gh = NULL; | |
978 | gl->gl_req_bh = NULL; | |
979 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
980 | run_queue(gl); | |
981 | spin_unlock(&gl->gl_spin); | |
982 | ||
983 | gfs2_glock_put(gl); | |
984 | ||
985 | if (gh) { | |
986 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) | |
987 | gfs2_holder_put(gh); | |
988 | else | |
989 | complete(&gh->gh_wait); | |
990 | } | |
991 | } | |
992 | ||
993 | /** | |
994 | * gfs2_glock_drop_th - call into the lock module to unlock a lock | |
995 | * @gl: the glock | |
996 | * | |
997 | */ | |
998 | ||
999 | void gfs2_glock_drop_th(struct gfs2_glock *gl) | |
1000 | { | |
1001 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1002 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1003 | unsigned int ret; |
1004 | ||
1005 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1006 | gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders)); | |
1007 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); | |
1008 | ||
1009 | if (gl->gl_state == LM_ST_EXCLUSIVE) { | |
1010 | if (glops->go_sync) | |
ec45d9f5 | 1011 | glops->go_sync(gl, DIO_METADATA | DIO_DATA | DIO_RELEASE); |
b3b94faa DT |
1012 | } |
1013 | ||
1014 | gfs2_glock_hold(gl); | |
1015 | gl->gl_req_bh = drop_bh; | |
1016 | ||
b3b94faa DT |
1017 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
1018 | ||
1019 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) | |
1020 | return; | |
1021 | ||
1022 | if (!ret) | |
1023 | drop_bh(gl, ret); | |
1024 | else | |
1025 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); | |
1026 | } | |
1027 | ||
1028 | /** | |
1029 | * do_cancels - cancel requests for locks stuck waiting on an expire flag | |
1030 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock | |
1031 | * | |
1032 | * Don't cancel GL_NOCANCEL requests. | |
1033 | */ | |
1034 | ||
1035 | static void do_cancels(struct gfs2_holder *gh) | |
1036 | { | |
1037 | struct gfs2_glock *gl = gh->gh_gl; | |
1038 | ||
1039 | spin_lock(&gl->gl_spin); | |
1040 | ||
1041 | while (gl->gl_req_gh != gh && | |
1042 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1043 | !list_empty(&gh->gh_list)) { | |
1044 | if (gl->gl_req_bh && | |
1045 | !(gl->gl_req_gh && | |
1046 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { | |
1047 | spin_unlock(&gl->gl_spin); | |
1048 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); | |
1049 | msleep(100); | |
1050 | spin_lock(&gl->gl_spin); | |
1051 | } else { | |
1052 | spin_unlock(&gl->gl_spin); | |
1053 | msleep(100); | |
1054 | spin_lock(&gl->gl_spin); | |
1055 | } | |
1056 | } | |
1057 | ||
1058 | spin_unlock(&gl->gl_spin); | |
1059 | } | |
1060 | ||
1061 | /** | |
1062 | * glock_wait_internal - wait on a glock acquisition | |
1063 | * @gh: the glock holder | |
1064 | * | |
1065 | * Returns: 0 on success | |
1066 | */ | |
1067 | ||
1068 | static int glock_wait_internal(struct gfs2_holder *gh) | |
1069 | { | |
1070 | struct gfs2_glock *gl = gh->gh_gl; | |
1071 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1072 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1073 | |
1074 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) | |
1075 | return -EIO; | |
1076 | ||
1077 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
1078 | spin_lock(&gl->gl_spin); | |
1079 | if (gl->gl_req_gh != gh && | |
1080 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1081 | !list_empty(&gh->gh_list)) { | |
1082 | list_del_init(&gh->gh_list); | |
1083 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
1084 | run_queue(gl); |
1085 | spin_unlock(&gl->gl_spin); | |
1086 | return gh->gh_error; | |
1087 | } | |
1088 | spin_unlock(&gl->gl_spin); | |
1089 | } | |
1090 | ||
1091 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1092 | do_cancels(gh); | |
1093 | ||
1094 | wait_for_completion(&gh->gh_wait); | |
1095 | ||
1096 | if (gh->gh_error) | |
1097 | return gh->gh_error; | |
1098 | ||
1099 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); | |
1100 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, | |
1101 | gh->gh_state, | |
1102 | gh->gh_flags)); | |
1103 | ||
1104 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { | |
1105 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1106 | ||
1107 | if (glops->go_lock) { | |
1108 | gh->gh_error = glops->go_lock(gh); | |
1109 | if (gh->gh_error) { | |
1110 | spin_lock(&gl->gl_spin); | |
1111 | list_del_init(&gh->gh_list); | |
b3b94faa DT |
1112 | spin_unlock(&gl->gl_spin); |
1113 | } | |
1114 | } | |
1115 | ||
1116 | spin_lock(&gl->gl_spin); | |
1117 | gl->gl_req_gh = NULL; | |
1118 | gl->gl_req_bh = NULL; | |
1119 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
1120 | run_queue(gl); |
1121 | spin_unlock(&gl->gl_spin); | |
1122 | } | |
1123 | ||
1124 | return gh->gh_error; | |
1125 | } | |
1126 | ||
1127 | static inline struct gfs2_holder * | |
1128 | find_holder_by_owner(struct list_head *head, struct task_struct *owner) | |
1129 | { | |
1130 | struct gfs2_holder *gh; | |
1131 | ||
1132 | list_for_each_entry(gh, head, gh_list) { | |
1133 | if (gh->gh_owner == owner) | |
1134 | return gh; | |
1135 | } | |
1136 | ||
1137 | return NULL; | |
1138 | } | |
1139 | ||
b3b94faa DT |
1140 | /** |
1141 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
1142 | * @gh: the holder structure to add | |
1143 | * | |
1144 | */ | |
1145 | ||
1146 | static void add_to_queue(struct gfs2_holder *gh) | |
1147 | { | |
1148 | struct gfs2_glock *gl = gh->gh_gl; | |
1149 | struct gfs2_holder *existing; | |
1150 | ||
190562bd SW |
1151 | BUG_ON(!gh->gh_owner); |
1152 | ||
b3b94faa DT |
1153 | existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner); |
1154 | if (existing) { | |
5965b1f4 | 1155 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
86384605 AD |
1156 | printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid); |
1157 | printk(KERN_INFO "lock type : %d lock state : %d\n", | |
1158 | existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state); | |
5965b1f4 | 1159 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); |
86384605 AD |
1160 | printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid); |
1161 | printk(KERN_INFO "lock type : %d lock state : %d\n", | |
1162 | gl->gl_name.ln_type, gl->gl_state); | |
5965b1f4 | 1163 | BUG(); |
b3b94faa DT |
1164 | } |
1165 | ||
1166 | existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner); | |
1167 | if (existing) { | |
5965b1f4 SW |
1168 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
1169 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); | |
1170 | BUG(); | |
b3b94faa DT |
1171 | } |
1172 | ||
b3b94faa DT |
1173 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
1174 | list_add(&gh->gh_list, &gl->gl_waiters3); | |
1175 | else | |
1176 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); | |
1177 | } | |
1178 | ||
1179 | /** | |
1180 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1181 | * @gh: the holder structure | |
1182 | * | |
1183 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1184 | * | |
1185 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1186 | */ | |
1187 | ||
1188 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1189 | { | |
1190 | struct gfs2_glock *gl = gh->gh_gl; | |
1191 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1192 | int error = 0; | |
1193 | ||
320dd101 | 1194 | restart: |
b3b94faa DT |
1195 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
1196 | set_bit(HIF_ABORTED, &gh->gh_iflags); | |
1197 | return -EIO; | |
1198 | } | |
1199 | ||
1200 | set_bit(HIF_PROMOTE, &gh->gh_iflags); | |
1201 | ||
1202 | spin_lock(&gl->gl_spin); | |
1203 | add_to_queue(gh); | |
1204 | run_queue(gl); | |
1205 | spin_unlock(&gl->gl_spin); | |
1206 | ||
1207 | if (!(gh->gh_flags & GL_ASYNC)) { | |
1208 | error = glock_wait_internal(gh); | |
1209 | if (error == GLR_CANCELED) { | |
190562bd | 1210 | msleep(100); |
b3b94faa DT |
1211 | goto restart; |
1212 | } | |
1213 | } | |
1214 | ||
1215 | clear_bit(GLF_PREFETCH, &gl->gl_flags); | |
1216 | ||
320dd101 SW |
1217 | if (error == GLR_TRYFAILED && (gh->gh_flags & GL_DUMP)) |
1218 | dump_glock(gl); | |
1219 | ||
b3b94faa DT |
1220 | return error; |
1221 | } | |
1222 | ||
1223 | /** | |
1224 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1225 | * @gh: the holder | |
1226 | * | |
1227 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1228 | */ | |
1229 | ||
1230 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1231 | { | |
1232 | struct gfs2_glock *gl = gh->gh_gl; | |
1233 | int ready = 0; | |
1234 | ||
1235 | spin_lock(&gl->gl_spin); | |
1236 | ||
1237 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1238 | ready = 1; | |
1239 | else if (list_empty(&gh->gh_list)) { | |
1240 | if (gh->gh_error == GLR_CANCELED) { | |
1241 | spin_unlock(&gl->gl_spin); | |
190562bd | 1242 | msleep(100); |
b3b94faa DT |
1243 | if (gfs2_glock_nq(gh)) |
1244 | return 1; | |
1245 | return 0; | |
1246 | } else | |
1247 | ready = 1; | |
1248 | } | |
1249 | ||
1250 | spin_unlock(&gl->gl_spin); | |
1251 | ||
1252 | return ready; | |
1253 | } | |
1254 | ||
1255 | /** | |
1256 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC | |
1257 | * @gh: the holder structure | |
1258 | * | |
1259 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1260 | */ | |
1261 | ||
1262 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
1263 | { | |
1264 | int error; | |
1265 | ||
1266 | error = glock_wait_internal(gh); | |
1267 | if (error == GLR_CANCELED) { | |
190562bd | 1268 | msleep(100); |
b3b94faa DT |
1269 | gh->gh_flags &= ~GL_ASYNC; |
1270 | error = gfs2_glock_nq(gh); | |
1271 | } | |
1272 | ||
1273 | return error; | |
1274 | } | |
1275 | ||
1276 | /** | |
1277 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1278 | * @gh: the glock holder | |
1279 | * | |
1280 | */ | |
1281 | ||
1282 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1283 | { | |
1284 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1285 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa | 1286 | |
b3b94faa DT |
1287 | if (gh->gh_flags & GL_NOCACHE) |
1288 | handle_callback(gl, LM_ST_UNLOCKED); | |
1289 | ||
1290 | gfs2_glmutex_lock(gl); | |
1291 | ||
1292 | spin_lock(&gl->gl_spin); | |
1293 | list_del_init(&gh->gh_list); | |
1294 | ||
1295 | if (list_empty(&gl->gl_holders)) { | |
1296 | spin_unlock(&gl->gl_spin); | |
1297 | ||
1298 | if (glops->go_unlock) | |
1299 | glops->go_unlock(gh); | |
1300 | ||
b3b94faa DT |
1301 | gl->gl_stamp = jiffies; |
1302 | ||
1303 | spin_lock(&gl->gl_spin); | |
1304 | } | |
1305 | ||
1306 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1307 | run_queue(gl); | |
1308 | spin_unlock(&gl->gl_spin); | |
1309 | } | |
1310 | ||
1311 | /** | |
1312 | * gfs2_glock_prefetch - Try to prefetch a glock | |
1313 | * @gl: the glock | |
1314 | * @state: the state to prefetch in | |
1315 | * @flags: flags passed to go_xmote_th() | |
1316 | * | |
1317 | */ | |
1318 | ||
08bc2dbc AB |
1319 | static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state, |
1320 | int flags) | |
b3b94faa | 1321 | { |
8fb4b536 | 1322 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1323 | |
1324 | spin_lock(&gl->gl_spin); | |
1325 | ||
1326 | if (test_bit(GLF_LOCK, &gl->gl_flags) || | |
1327 | !list_empty(&gl->gl_holders) || | |
1328 | !list_empty(&gl->gl_waiters1) || | |
1329 | !list_empty(&gl->gl_waiters2) || | |
1330 | !list_empty(&gl->gl_waiters3) || | |
1331 | relaxed_state_ok(gl->gl_state, state, flags)) { | |
1332 | spin_unlock(&gl->gl_spin); | |
1333 | return; | |
1334 | } | |
1335 | ||
1336 | set_bit(GLF_PREFETCH, &gl->gl_flags); | |
1337 | set_bit(GLF_LOCK, &gl->gl_flags); | |
1338 | spin_unlock(&gl->gl_spin); | |
1339 | ||
1340 | glops->go_xmote_th(gl, state, flags); | |
b3b94faa DT |
1341 | } |
1342 | ||
b3b94faa DT |
1343 | static void greedy_work(void *data) |
1344 | { | |
e7f5c01c | 1345 | struct greedy *gr = data; |
b3b94faa DT |
1346 | struct gfs2_holder *gh = &gr->gr_gh; |
1347 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1348 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1349 | |
1350 | clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1351 | ||
1352 | if (glops->go_greedy) | |
1353 | glops->go_greedy(gl); | |
1354 | ||
1355 | spin_lock(&gl->gl_spin); | |
1356 | ||
1357 | if (list_empty(&gl->gl_waiters2)) { | |
1358 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1359 | spin_unlock(&gl->gl_spin); | |
1360 | gfs2_holder_uninit(gh); | |
1361 | kfree(gr); | |
1362 | } else { | |
1363 | gfs2_glock_hold(gl); | |
1364 | list_add_tail(&gh->gh_list, &gl->gl_waiters2); | |
1365 | run_queue(gl); | |
1366 | spin_unlock(&gl->gl_spin); | |
1367 | gfs2_glock_put(gl); | |
1368 | } | |
1369 | } | |
1370 | ||
1371 | /** | |
1372 | * gfs2_glock_be_greedy - | |
1373 | * @gl: | |
1374 | * @time: | |
1375 | * | |
1376 | * Returns: 0 if go_greedy will be called, 1 otherwise | |
1377 | */ | |
1378 | ||
1379 | int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time) | |
1380 | { | |
1381 | struct greedy *gr; | |
1382 | struct gfs2_holder *gh; | |
1383 | ||
feaa7bba | 1384 | if (!time || gl->gl_sbd->sd_args.ar_localcaching || |
b3b94faa DT |
1385 | test_and_set_bit(GLF_GREEDY, &gl->gl_flags)) |
1386 | return 1; | |
1387 | ||
1388 | gr = kmalloc(sizeof(struct greedy), GFP_KERNEL); | |
1389 | if (!gr) { | |
1390 | clear_bit(GLF_GREEDY, &gl->gl_flags); | |
1391 | return 1; | |
1392 | } | |
1393 | gh = &gr->gr_gh; | |
1394 | ||
579b78a4 | 1395 | gfs2_holder_init(gl, 0, 0, gh); |
b3b94faa DT |
1396 | set_bit(HIF_GREEDY, &gh->gh_iflags); |
1397 | INIT_WORK(&gr->gr_work, greedy_work, gr); | |
1398 | ||
1399 | set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags); | |
1400 | schedule_delayed_work(&gr->gr_work, time); | |
1401 | ||
1402 | return 0; | |
1403 | } | |
1404 | ||
b3b94faa DT |
1405 | /** |
1406 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1407 | * @gh: the holder structure | |
1408 | * | |
1409 | */ | |
1410 | ||
1411 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1412 | { | |
1413 | gfs2_glock_dq(gh); | |
1414 | gfs2_holder_uninit(gh); | |
1415 | } | |
1416 | ||
1417 | /** | |
1418 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1419 | * @sdp: the filesystem | |
1420 | * @number: the lock number | |
1421 | * @glops: the glock operations for the type of glock | |
1422 | * @state: the state to acquire the glock in | |
1423 | * @flags: modifier flags for the aquisition | |
1424 | * @gh: the struct gfs2_holder | |
1425 | * | |
1426 | * Returns: errno | |
1427 | */ | |
1428 | ||
1429 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, uint64_t number, | |
8fb4b536 SW |
1430 | const struct gfs2_glock_operations *glops, |
1431 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1432 | { |
1433 | struct gfs2_glock *gl; | |
1434 | int error; | |
1435 | ||
1436 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1437 | if (!error) { | |
1438 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1439 | gfs2_glock_put(gl); | |
1440 | } | |
1441 | ||
1442 | return error; | |
1443 | } | |
1444 | ||
1445 | /** | |
1446 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1447 | * @arg_a: the first structure | |
1448 | * @arg_b: the second structure | |
1449 | * | |
1450 | */ | |
1451 | ||
1452 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1453 | { | |
1454 | struct gfs2_holder *gh_a = *(struct gfs2_holder **)arg_a; | |
1455 | struct gfs2_holder *gh_b = *(struct gfs2_holder **)arg_b; | |
1456 | struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1457 | struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
1458 | int ret = 0; | |
1459 | ||
1460 | if (a->ln_number > b->ln_number) | |
1461 | ret = 1; | |
1462 | else if (a->ln_number < b->ln_number) | |
1463 | ret = -1; | |
1464 | else { | |
1465 | if (gh_a->gh_state == LM_ST_SHARED && | |
1466 | gh_b->gh_state == LM_ST_EXCLUSIVE) | |
1467 | ret = 1; | |
1468 | else if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && | |
1469 | (gh_b->gh_flags & GL_LOCAL_EXCL)) | |
1470 | ret = 1; | |
1471 | } | |
1472 | ||
1473 | return ret; | |
1474 | } | |
1475 | ||
1476 | /** | |
1477 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1478 | * @num_gh: the number of structures | |
1479 | * @ghs: an array of struct gfs2_holder structures | |
1480 | * | |
1481 | * Returns: 0 on success (all glocks acquired), | |
1482 | * errno on failure (no glocks acquired) | |
1483 | */ | |
1484 | ||
1485 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1486 | struct gfs2_holder **p) | |
1487 | { | |
1488 | unsigned int x; | |
1489 | int error = 0; | |
1490 | ||
1491 | for (x = 0; x < num_gh; x++) | |
1492 | p[x] = &ghs[x]; | |
1493 | ||
1494 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1495 | ||
1496 | for (x = 0; x < num_gh; x++) { | |
1497 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1498 | ||
1499 | error = gfs2_glock_nq(p[x]); | |
1500 | if (error) { | |
1501 | while (x--) | |
1502 | gfs2_glock_dq(p[x]); | |
1503 | break; | |
1504 | } | |
1505 | } | |
1506 | ||
1507 | return error; | |
1508 | } | |
1509 | ||
1510 | /** | |
1511 | * gfs2_glock_nq_m - acquire multiple glocks | |
1512 | * @num_gh: the number of structures | |
1513 | * @ghs: an array of struct gfs2_holder structures | |
1514 | * | |
1515 | * Figure out how big an impact this function has. Either: | |
1516 | * 1) Replace this code with code that calls gfs2_glock_prefetch() | |
1517 | * 2) Forget async stuff and just call nq_m_sync() | |
1518 | * 3) Leave it like it is | |
1519 | * | |
1520 | * Returns: 0 on success (all glocks acquired), | |
1521 | * errno on failure (no glocks acquired) | |
1522 | */ | |
1523 | ||
1524 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1525 | { | |
1526 | int *e; | |
1527 | unsigned int x; | |
1528 | int borked = 0, serious = 0; | |
1529 | int error = 0; | |
1530 | ||
1531 | if (!num_gh) | |
1532 | return 0; | |
1533 | ||
1534 | if (num_gh == 1) { | |
1535 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1536 | return gfs2_glock_nq(ghs); | |
1537 | } | |
1538 | ||
1539 | e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL); | |
1540 | if (!e) | |
1541 | return -ENOMEM; | |
1542 | ||
1543 | for (x = 0; x < num_gh; x++) { | |
1544 | ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC; | |
1545 | error = gfs2_glock_nq(&ghs[x]); | |
1546 | if (error) { | |
1547 | borked = 1; | |
1548 | serious = error; | |
1549 | num_gh = x; | |
1550 | break; | |
1551 | } | |
1552 | } | |
1553 | ||
1554 | for (x = 0; x < num_gh; x++) { | |
1555 | error = e[x] = glock_wait_internal(&ghs[x]); | |
1556 | if (error) { | |
1557 | borked = 1; | |
1558 | if (error != GLR_TRYFAILED && error != GLR_CANCELED) | |
1559 | serious = error; | |
1560 | } | |
1561 | } | |
1562 | ||
1563 | if (!borked) { | |
1564 | kfree(e); | |
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | for (x = 0; x < num_gh; x++) | |
1569 | if (!e[x]) | |
1570 | gfs2_glock_dq(&ghs[x]); | |
1571 | ||
1572 | if (serious) | |
1573 | error = serious; | |
1574 | else { | |
1575 | for (x = 0; x < num_gh; x++) | |
1576 | gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags, | |
1577 | &ghs[x]); | |
1578 | error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e); | |
1579 | } | |
1580 | ||
1581 | kfree(e); | |
1582 | ||
1583 | return error; | |
1584 | } | |
1585 | ||
1586 | /** | |
1587 | * gfs2_glock_dq_m - release multiple glocks | |
1588 | * @num_gh: the number of structures | |
1589 | * @ghs: an array of struct gfs2_holder structures | |
1590 | * | |
1591 | */ | |
1592 | ||
1593 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1594 | { | |
1595 | unsigned int x; | |
1596 | ||
1597 | for (x = 0; x < num_gh; x++) | |
1598 | gfs2_glock_dq(&ghs[x]); | |
1599 | } | |
1600 | ||
1601 | /** | |
1602 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1603 | * @num_gh: the number of structures | |
1604 | * @ghs: an array of struct gfs2_holder structures | |
1605 | * | |
1606 | */ | |
1607 | ||
1608 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1609 | { | |
1610 | unsigned int x; | |
1611 | ||
1612 | for (x = 0; x < num_gh; x++) | |
1613 | gfs2_glock_dq_uninit(&ghs[x]); | |
1614 | } | |
1615 | ||
1616 | /** | |
1617 | * gfs2_glock_prefetch_num - prefetch a glock based on lock number | |
1618 | * @sdp: the filesystem | |
1619 | * @number: the lock number | |
1620 | * @glops: the glock operations for the type of glock | |
1621 | * @state: the state to acquire the glock in | |
1622 | * @flags: modifier flags for the aquisition | |
1623 | * | |
1624 | * Returns: errno | |
1625 | */ | |
1626 | ||
1627 | void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, uint64_t number, | |
8fb4b536 | 1628 | const struct gfs2_glock_operations *glops, |
b3b94faa DT |
1629 | unsigned int state, int flags) |
1630 | { | |
1631 | struct gfs2_glock *gl; | |
1632 | int error; | |
1633 | ||
1634 | if (atomic_read(&sdp->sd_reclaim_count) < | |
1635 | gfs2_tune_get(sdp, gt_reclaim_limit)) { | |
1636 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1637 | if (!error) { | |
1638 | gfs2_glock_prefetch(gl, state, flags); | |
1639 | gfs2_glock_put(gl); | |
1640 | } | |
1641 | } | |
1642 | } | |
1643 | ||
1644 | /** | |
1645 | * gfs2_lvb_hold - attach a LVB from a glock | |
1646 | * @gl: The glock in question | |
1647 | * | |
1648 | */ | |
1649 | ||
1650 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1651 | { | |
1652 | int error; | |
1653 | ||
1654 | gfs2_glmutex_lock(gl); | |
1655 | ||
1656 | if (!atomic_read(&gl->gl_lvb_count)) { | |
1657 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
1658 | if (error) { | |
1659 | gfs2_glmutex_unlock(gl); | |
1660 | return error; | |
1661 | } | |
1662 | gfs2_glock_hold(gl); | |
1663 | } | |
1664 | atomic_inc(&gl->gl_lvb_count); | |
1665 | ||
1666 | gfs2_glmutex_unlock(gl); | |
1667 | ||
1668 | return 0; | |
1669 | } | |
1670 | ||
1671 | /** | |
1672 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1673 | * @gl: The glock in question | |
1674 | * | |
1675 | */ | |
1676 | ||
1677 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1678 | { | |
1679 | gfs2_glock_hold(gl); | |
1680 | gfs2_glmutex_lock(gl); | |
1681 | ||
1682 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); | |
1683 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
1684 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1685 | gl->gl_lvb = NULL; | |
1686 | gfs2_glock_put(gl); | |
1687 | } | |
1688 | ||
1689 | gfs2_glmutex_unlock(gl); | |
1690 | gfs2_glock_put(gl); | |
1691 | } | |
1692 | ||
08bc2dbc | 1693 | #if 0 |
b3b94faa DT |
1694 | void gfs2_lvb_sync(struct gfs2_glock *gl) |
1695 | { | |
1696 | gfs2_glmutex_lock(gl); | |
1697 | ||
1698 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count)); | |
1699 | if (!gfs2_assert_warn(gl->gl_sbd, gfs2_glock_is_held_excl(gl))) | |
1700 | gfs2_lm_sync_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1701 | ||
1702 | gfs2_glmutex_unlock(gl); | |
1703 | } | |
08bc2dbc | 1704 | #endif /* 0 */ |
b3b94faa DT |
1705 | |
1706 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, | |
1707 | unsigned int state) | |
1708 | { | |
1709 | struct gfs2_glock *gl; | |
1710 | ||
1711 | gl = gfs2_glock_find(sdp, name); | |
1712 | if (!gl) | |
1713 | return; | |
1714 | ||
1715 | if (gl->gl_ops->go_callback) | |
1716 | gl->gl_ops->go_callback(gl, state); | |
1717 | handle_callback(gl, state); | |
1718 | ||
1719 | spin_lock(&gl->gl_spin); | |
1720 | run_queue(gl); | |
1721 | spin_unlock(&gl->gl_spin); | |
1722 | ||
1723 | gfs2_glock_put(gl); | |
1724 | } | |
1725 | ||
1726 | /** | |
1727 | * gfs2_glock_cb - Callback used by locking module | |
1728 | * @fsdata: Pointer to the superblock | |
1729 | * @type: Type of callback | |
1730 | * @data: Type dependent data pointer | |
1731 | * | |
1732 | * Called by the locking module when it wants to tell us something. | |
1733 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1734 | * a journal from another client needs to be recovered. | |
1735 | */ | |
1736 | ||
1737 | void gfs2_glock_cb(lm_fsdata_t *fsdata, unsigned int type, void *data) | |
1738 | { | |
1739 | struct gfs2_sbd *sdp = (struct gfs2_sbd *)fsdata; | |
1740 | ||
b3b94faa DT |
1741 | switch (type) { |
1742 | case LM_CB_NEED_E: | |
e7f5c01c | 1743 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
b3b94faa DT |
1744 | return; |
1745 | ||
1746 | case LM_CB_NEED_D: | |
e7f5c01c | 1747 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
b3b94faa DT |
1748 | return; |
1749 | ||
1750 | case LM_CB_NEED_S: | |
e7f5c01c | 1751 | blocking_cb(sdp, data, LM_ST_SHARED); |
b3b94faa DT |
1752 | return; |
1753 | ||
1754 | case LM_CB_ASYNC: { | |
e7f5c01c | 1755 | struct lm_async_cb *async = data; |
b3b94faa DT |
1756 | struct gfs2_glock *gl; |
1757 | ||
1758 | gl = gfs2_glock_find(sdp, &async->lc_name); | |
1759 | if (gfs2_assert_warn(sdp, gl)) | |
1760 | return; | |
1761 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) | |
1762 | gl->gl_req_bh(gl, async->lc_ret); | |
1763 | gfs2_glock_put(gl); | |
b3b94faa DT |
1764 | return; |
1765 | } | |
1766 | ||
1767 | case LM_CB_NEED_RECOVERY: | |
1768 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1769 | if (sdp->sd_recoverd_process) | |
1770 | wake_up_process(sdp->sd_recoverd_process); | |
1771 | return; | |
1772 | ||
1773 | case LM_CB_DROPLOCKS: | |
1774 | gfs2_gl_hash_clear(sdp, NO_WAIT); | |
1775 | gfs2_quota_scan(sdp); | |
1776 | return; | |
1777 | ||
1778 | default: | |
1779 | gfs2_assert_warn(sdp, 0); | |
1780 | return; | |
1781 | } | |
1782 | } | |
1783 | ||
b3b94faa DT |
1784 | /** |
1785 | * gfs2_iopen_go_callback - Try to kick the inode/vnode associated with an | |
1786 | * iopen glock from memory | |
1787 | * @io_gl: the iopen glock | |
1788 | * @state: the state into which the glock should be put | |
1789 | * | |
1790 | */ | |
1791 | ||
1792 | void gfs2_iopen_go_callback(struct gfs2_glock *io_gl, unsigned int state) | |
1793 | { | |
b3b94faa DT |
1794 | |
1795 | if (state != LM_ST_UNLOCKED) | |
1796 | return; | |
feaa7bba | 1797 | /* FIXME: remove this? */ |
b3b94faa DT |
1798 | } |
1799 | ||
1800 | /** | |
1801 | * demote_ok - Check to see if it's ok to unlock a glock | |
1802 | * @gl: the glock | |
1803 | * | |
1804 | * Returns: 1 if it's ok | |
1805 | */ | |
1806 | ||
1807 | static int demote_ok(struct gfs2_glock *gl) | |
1808 | { | |
1809 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1810 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1811 | int demote = 1; |
1812 | ||
1813 | if (test_bit(GLF_STICKY, &gl->gl_flags)) | |
1814 | demote = 0; | |
1815 | else if (test_bit(GLF_PREFETCH, &gl->gl_flags)) | |
1816 | demote = time_after_eq(jiffies, | |
1817 | gl->gl_stamp + | |
1818 | gfs2_tune_get(sdp, gt_prefetch_secs) * HZ); | |
1819 | else if (glops->go_demote_ok) | |
1820 | demote = glops->go_demote_ok(gl); | |
1821 | ||
1822 | return demote; | |
1823 | } | |
1824 | ||
1825 | /** | |
1826 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
1827 | * @gl: the glock | |
1828 | * | |
1829 | */ | |
1830 | ||
1831 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
1832 | { | |
1833 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1834 | ||
1835 | spin_lock(&sdp->sd_reclaim_lock); | |
1836 | if (list_empty(&gl->gl_reclaim)) { | |
1837 | gfs2_glock_hold(gl); | |
1838 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); | |
1839 | atomic_inc(&sdp->sd_reclaim_count); | |
1840 | } | |
1841 | spin_unlock(&sdp->sd_reclaim_lock); | |
1842 | ||
1843 | wake_up(&sdp->sd_reclaim_wq); | |
1844 | } | |
1845 | ||
1846 | /** | |
1847 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list | |
1848 | * @sdp: the filesystem | |
1849 | * | |
1850 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a | |
1851 | * different glock and we notice that there are a lot of glocks in the | |
1852 | * reclaim list. | |
1853 | * | |
1854 | */ | |
1855 | ||
1856 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) | |
1857 | { | |
1858 | struct gfs2_glock *gl; | |
1859 | ||
1860 | spin_lock(&sdp->sd_reclaim_lock); | |
1861 | if (list_empty(&sdp->sd_reclaim_list)) { | |
1862 | spin_unlock(&sdp->sd_reclaim_lock); | |
1863 | return; | |
1864 | } | |
1865 | gl = list_entry(sdp->sd_reclaim_list.next, | |
1866 | struct gfs2_glock, gl_reclaim); | |
1867 | list_del_init(&gl->gl_reclaim); | |
1868 | spin_unlock(&sdp->sd_reclaim_lock); | |
1869 | ||
1870 | atomic_dec(&sdp->sd_reclaim_count); | |
1871 | atomic_inc(&sdp->sd_reclaimed); | |
1872 | ||
1873 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa DT |
1874 | if (queue_empty(gl, &gl->gl_holders) && |
1875 | gl->gl_state != LM_ST_UNLOCKED && | |
1876 | demote_ok(gl)) | |
1877 | handle_callback(gl, LM_ST_UNLOCKED); | |
1878 | gfs2_glmutex_unlock(gl); | |
1879 | } | |
1880 | ||
1881 | gfs2_glock_put(gl); | |
1882 | } | |
1883 | ||
1884 | /** | |
1885 | * examine_bucket - Call a function for glock in a hash bucket | |
1886 | * @examiner: the function | |
1887 | * @sdp: the filesystem | |
1888 | * @bucket: the bucket | |
1889 | * | |
1890 | * Returns: 1 if the bucket has entries | |
1891 | */ | |
1892 | ||
1893 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
1894 | struct gfs2_gl_hash_bucket *bucket) | |
1895 | { | |
1896 | struct glock_plug plug; | |
1897 | struct list_head *tmp; | |
1898 | struct gfs2_glock *gl; | |
1899 | int entries; | |
1900 | ||
1901 | /* Add "plug" to end of bucket list, work back up list from there */ | |
1902 | memset(&plug.gl_flags, 0, sizeof(unsigned long)); | |
1903 | set_bit(GLF_PLUG, &plug.gl_flags); | |
1904 | ||
1905 | write_lock(&bucket->hb_lock); | |
1906 | list_add(&plug.gl_list, &bucket->hb_list); | |
1907 | write_unlock(&bucket->hb_lock); | |
1908 | ||
1909 | for (;;) { | |
1910 | write_lock(&bucket->hb_lock); | |
1911 | ||
1912 | for (;;) { | |
1913 | tmp = plug.gl_list.next; | |
1914 | ||
1915 | if (tmp == &bucket->hb_list) { | |
1916 | list_del(&plug.gl_list); | |
1917 | entries = !list_empty(&bucket->hb_list); | |
1918 | write_unlock(&bucket->hb_lock); | |
1919 | return entries; | |
1920 | } | |
1921 | gl = list_entry(tmp, struct gfs2_glock, gl_list); | |
1922 | ||
1923 | /* Move plug up list */ | |
1924 | list_move(&plug.gl_list, &gl->gl_list); | |
1925 | ||
1926 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
1927 | continue; | |
1928 | ||
1929 | /* examiner() must glock_put() */ | |
1930 | gfs2_glock_hold(gl); | |
1931 | ||
1932 | break; | |
1933 | } | |
1934 | ||
1935 | write_unlock(&bucket->hb_lock); | |
1936 | ||
1937 | examiner(gl); | |
1938 | } | |
1939 | } | |
1940 | ||
1941 | /** | |
1942 | * scan_glock - look at a glock and see if we can reclaim it | |
1943 | * @gl: the glock to look at | |
1944 | * | |
1945 | */ | |
1946 | ||
1947 | static void scan_glock(struct gfs2_glock *gl) | |
1948 | { | |
a2242db0 SW |
1949 | if (gl->gl_ops == &gfs2_inode_glops) |
1950 | goto out; | |
1951 | ||
b3b94faa | 1952 | if (gfs2_glmutex_trylock(gl)) { |
b3b94faa DT |
1953 | if (queue_empty(gl, &gl->gl_holders) && |
1954 | gl->gl_state != LM_ST_UNLOCKED && | |
1955 | demote_ok(gl)) | |
1956 | goto out_schedule; | |
b3b94faa DT |
1957 | gfs2_glmutex_unlock(gl); |
1958 | } | |
a2242db0 | 1959 | out: |
b3b94faa | 1960 | gfs2_glock_put(gl); |
b3b94faa DT |
1961 | return; |
1962 | ||
627add2d | 1963 | out_schedule: |
b3b94faa DT |
1964 | gfs2_glmutex_unlock(gl); |
1965 | gfs2_glock_schedule_for_reclaim(gl); | |
1966 | gfs2_glock_put(gl); | |
1967 | } | |
1968 | ||
1969 | /** | |
1970 | * gfs2_scand_internal - Look for glocks and inodes to toss from memory | |
1971 | * @sdp: the filesystem | |
1972 | * | |
1973 | */ | |
1974 | ||
1975 | void gfs2_scand_internal(struct gfs2_sbd *sdp) | |
1976 | { | |
1977 | unsigned int x; | |
1978 | ||
1979 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
1980 | examine_bucket(scan_glock, sdp, &sdp->sd_gl_hash[x]); | |
1981 | cond_resched(); | |
1982 | } | |
1983 | } | |
1984 | ||
1985 | /** | |
1986 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1987 | * @gl: the glock to look at | |
1988 | * | |
1989 | */ | |
1990 | ||
1991 | static void clear_glock(struct gfs2_glock *gl) | |
1992 | { | |
1993 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1994 | int released; | |
1995 | ||
1996 | spin_lock(&sdp->sd_reclaim_lock); | |
1997 | if (!list_empty(&gl->gl_reclaim)) { | |
1998 | list_del_init(&gl->gl_reclaim); | |
1999 | atomic_dec(&sdp->sd_reclaim_count); | |
190562bd | 2000 | spin_unlock(&sdp->sd_reclaim_lock); |
b3b94faa DT |
2001 | released = gfs2_glock_put(gl); |
2002 | gfs2_assert(sdp, !released); | |
190562bd SW |
2003 | } else { |
2004 | spin_unlock(&sdp->sd_reclaim_lock); | |
b3b94faa | 2005 | } |
b3b94faa DT |
2006 | |
2007 | if (gfs2_glmutex_trylock(gl)) { | |
b3b94faa DT |
2008 | if (queue_empty(gl, &gl->gl_holders) && |
2009 | gl->gl_state != LM_ST_UNLOCKED) | |
2010 | handle_callback(gl, LM_ST_UNLOCKED); | |
2011 | ||
2012 | gfs2_glmutex_unlock(gl); | |
2013 | } | |
2014 | ||
2015 | gfs2_glock_put(gl); | |
2016 | } | |
2017 | ||
2018 | /** | |
2019 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
2020 | * @sdp: the filesystem | |
2021 | * @wait: wait until it's all gone | |
2022 | * | |
2023 | * Called when unmounting the filesystem, or when inter-node lock manager | |
2024 | * requests DROPLOCKS because it is running out of capacity. | |
2025 | */ | |
2026 | ||
2027 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) | |
2028 | { | |
2029 | unsigned long t; | |
2030 | unsigned int x; | |
2031 | int cont; | |
2032 | ||
2033 | t = jiffies; | |
2034 | ||
2035 | for (;;) { | |
2036 | cont = 0; | |
2037 | ||
2038 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
2039 | if (examine_bucket(clear_glock, sdp, | |
2040 | &sdp->sd_gl_hash[x])) | |
2041 | cont = 1; | |
2042 | ||
2043 | if (!wait || !cont) | |
2044 | break; | |
2045 | ||
2046 | if (time_after_eq(jiffies, | |
2047 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
2048 | fs_warn(sdp, "Unmount seems to be stalled. " | |
2049 | "Dumping lock state...\n"); | |
2050 | gfs2_dump_lockstate(sdp); | |
2051 | t = jiffies; | |
2052 | } | |
2053 | ||
b3b94faa | 2054 | invalidate_inodes(sdp->sd_vfs); |
fd88de56 | 2055 | msleep(10); |
b3b94faa DT |
2056 | } |
2057 | } | |
2058 | ||
2059 | /* | |
2060 | * Diagnostic routines to help debug distributed deadlock | |
2061 | */ | |
2062 | ||
2063 | /** | |
2064 | * dump_holder - print information about a glock holder | |
2065 | * @str: a string naming the type of holder | |
2066 | * @gh: the glock holder | |
2067 | * | |
2068 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2069 | */ | |
2070 | ||
2071 | static int dump_holder(char *str, struct gfs2_holder *gh) | |
2072 | { | |
2073 | unsigned int x; | |
2074 | int error = -ENOBUFS; | |
2075 | ||
d92a8d48 SW |
2076 | printk(KERN_INFO " %s\n", str); |
2077 | printk(KERN_INFO " owner = %ld\n", | |
b3b94faa | 2078 | (gh->gh_owner) ? (long)gh->gh_owner->pid : -1); |
d92a8d48 SW |
2079 | printk(KERN_INFO " gh_state = %u\n", gh->gh_state); |
2080 | printk(KERN_INFO " gh_flags ="); | |
b3b94faa DT |
2081 | for (x = 0; x < 32; x++) |
2082 | if (gh->gh_flags & (1 << x)) | |
2083 | printk(" %u", x); | |
2084 | printk(" \n"); | |
d92a8d48 SW |
2085 | printk(KERN_INFO " error = %d\n", gh->gh_error); |
2086 | printk(KERN_INFO " gh_iflags ="); | |
b3b94faa DT |
2087 | for (x = 0; x < 32; x++) |
2088 | if (test_bit(x, &gh->gh_iflags)) | |
2089 | printk(" %u", x); | |
2090 | printk(" \n"); | |
d0dc80db | 2091 | print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip); |
b3b94faa DT |
2092 | |
2093 | error = 0; | |
2094 | ||
2095 | return error; | |
2096 | } | |
2097 | ||
2098 | /** | |
2099 | * dump_inode - print information about an inode | |
2100 | * @ip: the inode | |
2101 | * | |
2102 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2103 | */ | |
2104 | ||
2105 | static int dump_inode(struct gfs2_inode *ip) | |
2106 | { | |
2107 | unsigned int x; | |
2108 | int error = -ENOBUFS; | |
2109 | ||
d92a8d48 SW |
2110 | printk(KERN_INFO " Inode:\n"); |
2111 | printk(KERN_INFO " num = %llu %llu\n", | |
382066da SW |
2112 | (unsigned long long)ip->i_num.no_formal_ino, |
2113 | (unsigned long long)ip->i_num.no_addr); | |
d92a8d48 | 2114 | printk(KERN_INFO " type = %u\n", IF2DT(ip->i_di.di_mode)); |
d92a8d48 | 2115 | printk(KERN_INFO " i_flags ="); |
b3b94faa DT |
2116 | for (x = 0; x < 32; x++) |
2117 | if (test_bit(x, &ip->i_flags)) | |
2118 | printk(" %u", x); | |
2119 | printk(" \n"); | |
b3b94faa DT |
2120 | |
2121 | error = 0; | |
2122 | ||
2123 | return error; | |
2124 | } | |
2125 | ||
2126 | /** | |
2127 | * dump_glock - print information about a glock | |
2128 | * @gl: the glock | |
2129 | * @count: where we are in the buffer | |
2130 | * | |
2131 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
2132 | */ | |
2133 | ||
2134 | static int dump_glock(struct gfs2_glock *gl) | |
2135 | { | |
2136 | struct gfs2_holder *gh; | |
2137 | unsigned int x; | |
2138 | int error = -ENOBUFS; | |
2139 | ||
2140 | spin_lock(&gl->gl_spin); | |
2141 | ||
88721877 RC |
2142 | printk(KERN_INFO "Glock 0x%p (%u, %llu)\n", |
2143 | gl, | |
2144 | gl->gl_name.ln_type, | |
382066da | 2145 | (unsigned long long)gl->gl_name.ln_number); |
d92a8d48 | 2146 | printk(KERN_INFO " gl_flags ="); |
b3b94faa DT |
2147 | for (x = 0; x < 32; x++) |
2148 | if (test_bit(x, &gl->gl_flags)) | |
2149 | printk(" %u", x); | |
2150 | printk(" \n"); | |
d92a8d48 SW |
2151 | printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref.refcount)); |
2152 | printk(KERN_INFO " gl_state = %u\n", gl->gl_state); | |
320dd101 SW |
2153 | printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm); |
2154 | print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip); | |
d92a8d48 SW |
2155 | printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); |
2156 | printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); | |
2157 | printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); | |
2158 | printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no"); | |
2159 | printk(KERN_INFO " le = %s\n", | |
b3b94faa | 2160 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
d92a8d48 | 2161 | printk(KERN_INFO " reclaim = %s\n", |
b3b94faa DT |
2162 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); |
2163 | if (gl->gl_aspace) | |
88721877 RC |
2164 | printk(KERN_INFO " aspace = 0x%p nrpages = %lu\n", |
2165 | gl->gl_aspace, | |
2166 | gl->gl_aspace->i_mapping->nrpages); | |
b3b94faa | 2167 | else |
d92a8d48 SW |
2168 | printk(KERN_INFO " aspace = no\n"); |
2169 | printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count)); | |
b3b94faa DT |
2170 | if (gl->gl_req_gh) { |
2171 | error = dump_holder("Request", gl->gl_req_gh); | |
2172 | if (error) | |
2173 | goto out; | |
2174 | } | |
2175 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
2176 | error = dump_holder("Holder", gh); | |
2177 | if (error) | |
2178 | goto out; | |
2179 | } | |
2180 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { | |
2181 | error = dump_holder("Waiter1", gh); | |
2182 | if (error) | |
2183 | goto out; | |
2184 | } | |
2185 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
2186 | error = dump_holder("Waiter2", gh); | |
2187 | if (error) | |
2188 | goto out; | |
2189 | } | |
2190 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { | |
2191 | error = dump_holder("Waiter3", gh); | |
2192 | if (error) | |
2193 | goto out; | |
2194 | } | |
5c676f6d | 2195 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { |
b3b94faa DT |
2196 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && |
2197 | list_empty(&gl->gl_holders)) { | |
5c676f6d | 2198 | error = dump_inode(gl->gl_object); |
b3b94faa DT |
2199 | if (error) |
2200 | goto out; | |
2201 | } else { | |
2202 | error = -ENOBUFS; | |
d92a8d48 | 2203 | printk(KERN_INFO " Inode: busy\n"); |
b3b94faa DT |
2204 | } |
2205 | } | |
2206 | ||
2207 | error = 0; | |
2208 | ||
2209 | out: | |
2210 | spin_unlock(&gl->gl_spin); | |
2211 | ||
2212 | return error; | |
2213 | } | |
2214 | ||
2215 | /** | |
2216 | * gfs2_dump_lockstate - print out the current lockstate | |
2217 | * @sdp: the filesystem | |
2218 | * @ub: the buffer to copy the information into | |
2219 | * | |
2220 | * If @ub is NULL, dump the lockstate to the console. | |
2221 | * | |
2222 | */ | |
2223 | ||
08bc2dbc | 2224 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
b3b94faa DT |
2225 | { |
2226 | struct gfs2_gl_hash_bucket *bucket; | |
2227 | struct gfs2_glock *gl; | |
2228 | unsigned int x; | |
2229 | int error = 0; | |
2230 | ||
2231 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
2232 | bucket = &sdp->sd_gl_hash[x]; | |
2233 | ||
2234 | read_lock(&bucket->hb_lock); | |
2235 | ||
2236 | list_for_each_entry(gl, &bucket->hb_list, gl_list) { | |
2237 | if (test_bit(GLF_PLUG, &gl->gl_flags)) | |
2238 | continue; | |
2239 | ||
2240 | error = dump_glock(gl); | |
2241 | if (error) | |
2242 | break; | |
2243 | } | |
2244 | ||
2245 | read_unlock(&bucket->hb_lock); | |
2246 | ||
2247 | if (error) | |
2248 | break; | |
2249 | } | |
2250 | ||
2251 | ||
2252 | return error; | |
2253 | } | |
2254 |