Commit | Line | Data |
---|---|---|
b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
cf45b752 | 3 | * Copyright (C) 2004-2008 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> | |
d0dc80db | 18 | #include <linux/kallsyms.h> |
5c676f6d | 19 | #include <linux/gfs2_ondisk.h> |
24264434 | 20 | #include <linux/list.h> |
7d308590 | 21 | #include <linux/lm_interface.h> |
fee852e3 | 22 | #include <linux/wait.h> |
95d97b7d | 23 | #include <linux/module.h> |
61be084e | 24 | #include <linux/rwsem.h> |
b3b94faa | 25 | #include <asm/uaccess.h> |
7c52b166 RP |
26 | #include <linux/seq_file.h> |
27 | #include <linux/debugfs.h> | |
8fbbfd21 SW |
28 | #include <linux/kthread.h> |
29 | #include <linux/freezer.h> | |
c4f68a13 BM |
30 | #include <linux/workqueue.h> |
31 | #include <linux/jiffies.h> | |
b3b94faa DT |
32 | |
33 | #include "gfs2.h" | |
5c676f6d | 34 | #include "incore.h" |
b3b94faa DT |
35 | #include "glock.h" |
36 | #include "glops.h" | |
37 | #include "inode.h" | |
b3b94faa DT |
38 | #include "lops.h" |
39 | #include "meta_io.h" | |
40 | #include "quota.h" | |
41 | #include "super.h" | |
5c676f6d | 42 | #include "util.h" |
813e0c46 | 43 | #include "bmap.h" |
b3b94faa | 44 | |
37b2fa6a | 45 | struct gfs2_gl_hash_bucket { |
b6397893 | 46 | struct hlist_head hb_list; |
37b2fa6a SW |
47 | }; |
48 | ||
6802e340 SW |
49 | struct gfs2_glock_iter { |
50 | int hash; /* hash bucket index */ | |
51 | struct gfs2_sbd *sdp; /* incore superblock */ | |
52 | struct gfs2_glock *gl; /* current glock struct */ | |
53 | char string[512]; /* scratch space */ | |
7c52b166 RP |
54 | }; |
55 | ||
b3b94faa DT |
56 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
57 | ||
08bc2dbc | 58 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); |
6802e340 SW |
59 | static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl); |
60 | #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { __dump_glock(NULL, gl); BUG(); } } while(0) | |
61 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target); | |
c4f68a13 | 62 | |
61be084e | 63 | static DECLARE_RWSEM(gfs2_umount_flush_sem); |
7c52b166 | 64 | static struct dentry *gfs2_root; |
c4f68a13 | 65 | static struct workqueue_struct *glock_workqueue; |
97cc1025 SW |
66 | static LIST_HEAD(lru_list); |
67 | static atomic_t lru_count = ATOMIC_INIT(0); | |
68 | static spinlock_t lru_lock = SPIN_LOCK_UNLOCKED; | |
08bc2dbc | 69 | |
b6397893 | 70 | #define GFS2_GL_HASH_SHIFT 15 |
087efdd3 SW |
71 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
72 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) | |
73 | ||
85d1da67 | 74 | static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE]; |
04b933f2 | 75 | static struct dentry *gfs2_root; |
087efdd3 SW |
76 | |
77 | /* | |
78 | * Despite what you might think, the numbers below are not arbitrary :-) | |
79 | * They are taken from the ipv4 routing hash code, which is well tested | |
80 | * and thus should be nearly optimal. Later on we might tweek the numbers | |
81 | * but for now this should be fine. | |
82 | * | |
83 | * The reason for putting the locks in a separate array from the list heads | |
84 | * is that we can have fewer locks than list heads and save memory. We use | |
85 | * the same hash function for both, but with a different hash mask. | |
86 | */ | |
87 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ | |
88 | defined(CONFIG_PROVE_LOCKING) | |
89 | ||
90 | #ifdef CONFIG_LOCKDEP | |
91 | # define GL_HASH_LOCK_SZ 256 | |
92 | #else | |
93 | # if NR_CPUS >= 32 | |
94 | # define GL_HASH_LOCK_SZ 4096 | |
95 | # elif NR_CPUS >= 16 | |
96 | # define GL_HASH_LOCK_SZ 2048 | |
97 | # elif NR_CPUS >= 8 | |
98 | # define GL_HASH_LOCK_SZ 1024 | |
99 | # elif NR_CPUS >= 4 | |
100 | # define GL_HASH_LOCK_SZ 512 | |
101 | # else | |
102 | # define GL_HASH_LOCK_SZ 256 | |
103 | # endif | |
104 | #endif | |
105 | ||
106 | /* We never want more locks than chains */ | |
107 | #if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ | |
108 | # undef GL_HASH_LOCK_SZ | |
109 | # define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE | |
110 | #endif | |
111 | ||
112 | static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ]; | |
113 | ||
114 | static inline rwlock_t *gl_lock_addr(unsigned int x) | |
115 | { | |
94610610 | 116 | return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)]; |
087efdd3 SW |
117 | } |
118 | #else /* not SMP, so no spinlocks required */ | |
0ac23069 | 119 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
087efdd3 SW |
120 | { |
121 | return NULL; | |
122 | } | |
123 | #endif | |
85d1da67 | 124 | |
b3b94faa DT |
125 | /** |
126 | * gl_hash() - Turn glock number into hash bucket number | |
127 | * @lock: The glock number | |
128 | * | |
129 | * Returns: The number of the corresponding hash bucket | |
130 | */ | |
131 | ||
b8547856 SW |
132 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
133 | const struct lm_lockname *name) | |
b3b94faa DT |
134 | { |
135 | unsigned int h; | |
136 | ||
cd915493 | 137 | h = jhash(&name->ln_number, sizeof(u64), 0); |
b3b94faa | 138 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
b8547856 | 139 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
b3b94faa DT |
140 | h &= GFS2_GL_HASH_MASK; |
141 | ||
142 | return h; | |
143 | } | |
144 | ||
145 | /** | |
146 | * glock_free() - Perform a few checks and then release struct gfs2_glock | |
147 | * @gl: The glock to release | |
148 | * | |
149 | * Also calls lock module to release its internal structure for this glock. | |
150 | * | |
151 | */ | |
152 | ||
153 | static void glock_free(struct gfs2_glock *gl) | |
154 | { | |
155 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
156 | struct inode *aspace = gl->gl_aspace; | |
157 | ||
048bca22 | 158 | if (sdp->sd_lockstruct.ls_ops->lm_put_lock) |
da755fdb | 159 | sdp->sd_lockstruct.ls_ops->lm_put_lock(gl->gl_lock); |
b3b94faa DT |
160 | |
161 | if (aspace) | |
162 | gfs2_aspace_put(aspace); | |
163 | ||
164 | kmem_cache_free(gfs2_glock_cachep, gl); | |
b3b94faa DT |
165 | } |
166 | ||
167 | /** | |
168 | * gfs2_glock_hold() - increment reference count on glock | |
169 | * @gl: The glock to hold | |
170 | * | |
171 | */ | |
172 | ||
048786f1 | 173 | static void gfs2_glock_hold(struct gfs2_glock *gl) |
b3b94faa | 174 | { |
16feb9fe | 175 | atomic_inc(&gl->gl_ref); |
b3b94faa DT |
176 | } |
177 | ||
97cc1025 SW |
178 | /** |
179 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
180 | * @gl: the glock | |
181 | * | |
182 | */ | |
183 | ||
184 | static void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
185 | { | |
186 | spin_lock(&lru_lock); | |
187 | if (list_empty(&gl->gl_lru) && gl->gl_state != LM_ST_UNLOCKED) { | |
188 | list_add_tail(&gl->gl_lru, &lru_list); | |
189 | atomic_inc(&lru_count); | |
190 | } | |
191 | spin_unlock(&lru_lock); | |
192 | } | |
193 | ||
b3b94faa DT |
194 | /** |
195 | * gfs2_glock_put() - Decrement reference count on glock | |
196 | * @gl: The glock to put | |
197 | * | |
198 | */ | |
199 | ||
200 | int gfs2_glock_put(struct gfs2_glock *gl) | |
201 | { | |
b3b94faa DT |
202 | int rv = 0; |
203 | ||
087efdd3 | 204 | write_lock(gl_lock_addr(gl->gl_hash)); |
16feb9fe | 205 | if (atomic_dec_and_test(&gl->gl_ref)) { |
b6397893 | 206 | hlist_del(&gl->gl_list); |
087efdd3 | 207 | write_unlock(gl_lock_addr(gl->gl_hash)); |
97cc1025 SW |
208 | spin_lock(&lru_lock); |
209 | if (!list_empty(&gl->gl_lru)) { | |
210 | list_del_init(&gl->gl_lru); | |
211 | atomic_dec(&lru_count); | |
212 | } | |
213 | spin_unlock(&lru_lock); | |
6802e340 | 214 | GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_UNLOCKED); |
97cc1025 | 215 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_lru)); |
6802e340 | 216 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); |
b3b94faa DT |
217 | glock_free(gl); |
218 | rv = 1; | |
219 | goto out; | |
220 | } | |
087efdd3 | 221 | write_unlock(gl_lock_addr(gl->gl_hash)); |
97cc1025 SW |
222 | /* 1 for being hashed, 1 for having state != LM_ST_UNLOCKED */ |
223 | if (atomic_read(&gl->gl_ref) == 2) | |
224 | gfs2_glock_schedule_for_reclaim(gl); | |
a2242db0 | 225 | out: |
b3b94faa DT |
226 | return rv; |
227 | } | |
228 | ||
b3b94faa DT |
229 | /** |
230 | * search_bucket() - Find struct gfs2_glock by lock number | |
231 | * @bucket: the bucket to search | |
232 | * @name: The lock name | |
233 | * | |
234 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
235 | */ | |
236 | ||
37b2fa6a | 237 | static struct gfs2_glock *search_bucket(unsigned int hash, |
899be4d3 | 238 | const struct gfs2_sbd *sdp, |
d6a53727 | 239 | const struct lm_lockname *name) |
b3b94faa DT |
240 | { |
241 | struct gfs2_glock *gl; | |
b6397893 | 242 | struct hlist_node *h; |
b3b94faa | 243 | |
b6397893 | 244 | hlist_for_each_entry(gl, h, &gl_hash_table[hash].hb_list, gl_list) { |
b3b94faa DT |
245 | if (!lm_name_equal(&gl->gl_name, name)) |
246 | continue; | |
899be4d3 SW |
247 | if (gl->gl_sbd != sdp) |
248 | continue; | |
b3b94faa | 249 | |
16feb9fe | 250 | atomic_inc(&gl->gl_ref); |
b3b94faa DT |
251 | |
252 | return gl; | |
253 | } | |
254 | ||
255 | return NULL; | |
256 | } | |
257 | ||
258 | /** | |
259 | * gfs2_glock_find() - Find glock by lock number | |
260 | * @sdp: The GFS2 superblock | |
261 | * @name: The lock name | |
262 | * | |
263 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
264 | */ | |
265 | ||
85d1da67 | 266 | static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp, |
d6a53727 | 267 | const struct lm_lockname *name) |
b3b94faa | 268 | { |
37b2fa6a | 269 | unsigned int hash = gl_hash(sdp, name); |
b3b94faa DT |
270 | struct gfs2_glock *gl; |
271 | ||
087efdd3 | 272 | read_lock(gl_lock_addr(hash)); |
37b2fa6a | 273 | gl = search_bucket(hash, sdp, name); |
087efdd3 | 274 | read_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
275 | |
276 | return gl; | |
277 | } | |
278 | ||
6802e340 SW |
279 | /** |
280 | * may_grant - check if its ok to grant a new lock | |
281 | * @gl: The glock | |
282 | * @gh: The lock request which we wish to grant | |
283 | * | |
284 | * Returns: true if its ok to grant the lock | |
285 | */ | |
286 | ||
287 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) | |
288 | { | |
289 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); | |
290 | if ((gh->gh_state == LM_ST_EXCLUSIVE || | |
291 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) | |
292 | return 0; | |
293 | if (gl->gl_state == gh->gh_state) | |
294 | return 1; | |
295 | if (gh->gh_flags & GL_EXACT) | |
296 | return 0; | |
209806ab SW |
297 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
298 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) | |
299 | return 1; | |
300 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) | |
301 | return 1; | |
302 | } | |
6802e340 SW |
303 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
304 | return 1; | |
305 | return 0; | |
306 | } | |
307 | ||
308 | static void gfs2_holder_wake(struct gfs2_holder *gh) | |
309 | { | |
310 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
311 | smp_mb__after_clear_bit(); | |
312 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); | |
313 | } | |
314 | ||
315 | /** | |
316 | * do_promote - promote as many requests as possible on the current queue | |
317 | * @gl: The glock | |
318 | * | |
813e0c46 SW |
319 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
320 | * if a type specific operation is underway. | |
6802e340 SW |
321 | */ |
322 | ||
323 | static int do_promote(struct gfs2_glock *gl) | |
55ba474d HH |
324 | __releases(&gl->gl_spin) |
325 | __acquires(&gl->gl_spin) | |
6802e340 SW |
326 | { |
327 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
328 | struct gfs2_holder *gh, *tmp; | |
329 | int ret; | |
330 | ||
331 | restart: | |
332 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
333 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
334 | continue; | |
335 | if (may_grant(gl, gh)) { | |
336 | if (gh->gh_list.prev == &gl->gl_holders && | |
337 | glops->go_lock) { | |
338 | spin_unlock(&gl->gl_spin); | |
339 | /* FIXME: eliminate this eventually */ | |
340 | ret = glops->go_lock(gh); | |
341 | spin_lock(&gl->gl_spin); | |
342 | if (ret) { | |
813e0c46 SW |
343 | if (ret == 1) |
344 | return 2; | |
6802e340 SW |
345 | gh->gh_error = ret; |
346 | list_del_init(&gh->gh_list); | |
347 | gfs2_holder_wake(gh); | |
348 | goto restart; | |
349 | } | |
350 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
351 | gfs2_holder_wake(gh); | |
352 | goto restart; | |
353 | } | |
354 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
355 | gfs2_holder_wake(gh); | |
356 | continue; | |
357 | } | |
358 | if (gh->gh_list.prev == &gl->gl_holders) | |
359 | return 1; | |
360 | break; | |
361 | } | |
362 | return 0; | |
363 | } | |
364 | ||
365 | /** | |
366 | * do_error - Something unexpected has happened during a lock request | |
367 | * | |
368 | */ | |
369 | ||
370 | static inline void do_error(struct gfs2_glock *gl, const int ret) | |
371 | { | |
372 | struct gfs2_holder *gh, *tmp; | |
373 | ||
374 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
375 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
376 | continue; | |
377 | if (ret & LM_OUT_ERROR) | |
378 | gh->gh_error = -EIO; | |
379 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) | |
380 | gh->gh_error = GLR_TRYFAILED; | |
381 | else | |
382 | continue; | |
383 | list_del_init(&gh->gh_list); | |
384 | gfs2_holder_wake(gh); | |
385 | } | |
386 | } | |
387 | ||
388 | /** | |
389 | * find_first_waiter - find the first gh that's waiting for the glock | |
390 | * @gl: the glock | |
391 | */ | |
392 | ||
393 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) | |
394 | { | |
395 | struct gfs2_holder *gh; | |
396 | ||
397 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
398 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
399 | return gh; | |
400 | } | |
401 | return NULL; | |
402 | } | |
403 | ||
404 | /** | |
405 | * state_change - record that the glock is now in a different state | |
406 | * @gl: the glock | |
407 | * @new_state the new state | |
408 | * | |
409 | */ | |
410 | ||
411 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
412 | { | |
413 | int held1, held2; | |
414 | ||
415 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
416 | held2 = (new_state != LM_ST_UNLOCKED); | |
417 | ||
418 | if (held1 != held2) { | |
419 | if (held2) | |
420 | gfs2_glock_hold(gl); | |
421 | else | |
422 | gfs2_glock_put(gl); | |
423 | } | |
424 | ||
425 | gl->gl_state = new_state; | |
426 | gl->gl_tchange = jiffies; | |
427 | } | |
428 | ||
429 | static void gfs2_demote_wake(struct gfs2_glock *gl) | |
430 | { | |
431 | gl->gl_demote_state = LM_ST_EXCLUSIVE; | |
432 | clear_bit(GLF_DEMOTE, &gl->gl_flags); | |
433 | smp_mb__after_clear_bit(); | |
434 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); | |
435 | } | |
436 | ||
437 | /** | |
438 | * finish_xmote - The DLM has replied to one of our lock requests | |
439 | * @gl: The glock | |
440 | * @ret: The status from the DLM | |
441 | * | |
442 | */ | |
443 | ||
444 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) | |
445 | { | |
446 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
447 | struct gfs2_holder *gh; | |
448 | unsigned state = ret & LM_OUT_ST_MASK; | |
813e0c46 | 449 | int rv; |
6802e340 SW |
450 | |
451 | spin_lock(&gl->gl_spin); | |
452 | state_change(gl, state); | |
453 | gh = find_first_waiter(gl); | |
454 | ||
455 | /* Demote to UN request arrived during demote to SH or DF */ | |
456 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && | |
457 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) | |
458 | gl->gl_target = LM_ST_UNLOCKED; | |
459 | ||
460 | /* Check for state != intended state */ | |
461 | if (unlikely(state != gl->gl_target)) { | |
462 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { | |
463 | /* move to back of queue and try next entry */ | |
464 | if (ret & LM_OUT_CANCELED) { | |
465 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) | |
466 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
467 | gh = find_first_waiter(gl); | |
468 | gl->gl_target = gh->gh_state; | |
469 | goto retry; | |
470 | } | |
471 | /* Some error or failed "try lock" - report it */ | |
472 | if ((ret & LM_OUT_ERROR) || | |
473 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
474 | gl->gl_target = gl->gl_state; | |
475 | do_error(gl, ret); | |
476 | goto out; | |
477 | } | |
478 | } | |
479 | switch(state) { | |
480 | /* Unlocked due to conversion deadlock, try again */ | |
481 | case LM_ST_UNLOCKED: | |
482 | retry: | |
483 | do_xmote(gl, gh, gl->gl_target); | |
484 | break; | |
485 | /* Conversion fails, unlock and try again */ | |
486 | case LM_ST_SHARED: | |
487 | case LM_ST_DEFERRED: | |
488 | do_xmote(gl, gh, LM_ST_UNLOCKED); | |
489 | break; | |
490 | default: /* Everything else */ | |
491 | printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state); | |
492 | GLOCK_BUG_ON(gl, 1); | |
493 | } | |
494 | spin_unlock(&gl->gl_spin); | |
495 | gfs2_glock_put(gl); | |
496 | return; | |
497 | } | |
498 | ||
499 | /* Fast path - we got what we asked for */ | |
500 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) | |
501 | gfs2_demote_wake(gl); | |
502 | if (state != LM_ST_UNLOCKED) { | |
503 | if (glops->go_xmote_bh) { | |
6802e340 SW |
504 | spin_unlock(&gl->gl_spin); |
505 | rv = glops->go_xmote_bh(gl, gh); | |
506 | if (rv == -EAGAIN) | |
507 | return; | |
508 | spin_lock(&gl->gl_spin); | |
509 | if (rv) { | |
510 | do_error(gl, rv); | |
511 | goto out; | |
512 | } | |
513 | } | |
813e0c46 SW |
514 | rv = do_promote(gl); |
515 | if (rv == 2) | |
516 | goto out_locked; | |
6802e340 SW |
517 | } |
518 | out: | |
519 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
813e0c46 | 520 | out_locked: |
6802e340 SW |
521 | spin_unlock(&gl->gl_spin); |
522 | gfs2_glock_put(gl); | |
523 | } | |
524 | ||
525 | static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock, | |
526 | unsigned int cur_state, unsigned int req_state, | |
527 | unsigned int flags) | |
528 | { | |
529 | int ret = LM_OUT_ERROR; | |
048bca22 SW |
530 | |
531 | if (!sdp->sd_lockstruct.ls_ops->lm_lock) | |
532 | return req_state == LM_ST_UNLOCKED ? 0 : req_state; | |
533 | ||
6802e340 SW |
534 | if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
535 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, cur_state, | |
536 | req_state, flags); | |
537 | return ret; | |
538 | } | |
539 | ||
540 | /** | |
541 | * do_xmote - Calls the DLM to change the state of a lock | |
542 | * @gl: The lock state | |
543 | * @gh: The holder (only for promotes) | |
544 | * @target: The target lock state | |
545 | * | |
546 | */ | |
547 | ||
548 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) | |
55ba474d HH |
549 | __releases(&gl->gl_spin) |
550 | __acquires(&gl->gl_spin) | |
6802e340 SW |
551 | { |
552 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
553 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
554 | unsigned int lck_flags = gh ? gh->gh_flags : 0; | |
555 | int ret; | |
556 | ||
557 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | | |
558 | LM_FLAG_PRIORITY); | |
559 | BUG_ON(gl->gl_state == target); | |
560 | BUG_ON(gl->gl_state == gl->gl_target); | |
561 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && | |
562 | glops->go_inval) { | |
563 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
564 | do_error(gl, 0); /* Fail queued try locks */ | |
565 | } | |
566 | spin_unlock(&gl->gl_spin); | |
567 | if (glops->go_xmote_th) | |
568 | glops->go_xmote_th(gl); | |
569 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) | |
570 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); | |
571 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
572 | ||
573 | gfs2_glock_hold(gl); | |
574 | if (target != LM_ST_UNLOCKED && (gl->gl_state == LM_ST_SHARED || | |
575 | gl->gl_state == LM_ST_DEFERRED) && | |
576 | !(lck_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
577 | lck_flags |= LM_FLAG_TRY_1CB; | |
578 | ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, target, lck_flags); | |
579 | ||
580 | if (!(ret & LM_OUT_ASYNC)) { | |
581 | finish_xmote(gl, ret); | |
582 | gfs2_glock_hold(gl); | |
583 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
584 | gfs2_glock_put(gl); | |
585 | } else { | |
586 | GLOCK_BUG_ON(gl, ret != LM_OUT_ASYNC); | |
587 | } | |
588 | spin_lock(&gl->gl_spin); | |
589 | } | |
590 | ||
591 | /** | |
592 | * find_first_holder - find the first "holder" gh | |
593 | * @gl: the glock | |
594 | */ | |
595 | ||
596 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) | |
597 | { | |
598 | struct gfs2_holder *gh; | |
599 | ||
600 | if (!list_empty(&gl->gl_holders)) { | |
601 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
602 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
603 | return gh; | |
604 | } | |
605 | return NULL; | |
606 | } | |
607 | ||
608 | /** | |
609 | * run_queue - do all outstanding tasks related to a glock | |
610 | * @gl: The glock in question | |
611 | * @nonblock: True if we must not block in run_queue | |
612 | * | |
613 | */ | |
614 | ||
615 | static void run_queue(struct gfs2_glock *gl, const int nonblock) | |
55ba474d HH |
616 | __releases(&gl->gl_spin) |
617 | __acquires(&gl->gl_spin) | |
6802e340 SW |
618 | { |
619 | struct gfs2_holder *gh = NULL; | |
813e0c46 | 620 | int ret; |
6802e340 SW |
621 | |
622 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
623 | return; | |
624 | ||
625 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); | |
626 | ||
627 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && | |
628 | gl->gl_demote_state != gl->gl_state) { | |
629 | if (find_first_holder(gl)) | |
630 | goto out; | |
631 | if (nonblock) | |
632 | goto out_sched; | |
633 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); | |
265d529c | 634 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
6802e340 SW |
635 | gl->gl_target = gl->gl_demote_state; |
636 | } else { | |
637 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
638 | gfs2_demote_wake(gl); | |
813e0c46 SW |
639 | ret = do_promote(gl); |
640 | if (ret == 0) | |
6802e340 | 641 | goto out; |
813e0c46 SW |
642 | if (ret == 2) |
643 | return; | |
6802e340 SW |
644 | gh = find_first_waiter(gl); |
645 | gl->gl_target = gh->gh_state; | |
646 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
647 | do_error(gl, 0); /* Fail queued try locks */ | |
648 | } | |
649 | do_xmote(gl, gh, gl->gl_target); | |
650 | return; | |
651 | ||
652 | out_sched: | |
653 | gfs2_glock_hold(gl); | |
654 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
655 | gfs2_glock_put(gl); | |
656 | out: | |
657 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
658 | } | |
659 | ||
c4f68a13 BM |
660 | static void glock_work_func(struct work_struct *work) |
661 | { | |
6802e340 | 662 | unsigned long delay = 0; |
c4f68a13 BM |
663 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
664 | ||
6802e340 SW |
665 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) |
666 | finish_xmote(gl, gl->gl_reply); | |
c4f68a13 | 667 | spin_lock(&gl->gl_spin); |
265d529c SW |
668 | if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
669 | gl->gl_state != LM_ST_UNLOCKED && | |
670 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { | |
6802e340 SW |
671 | unsigned long holdtime, now = jiffies; |
672 | holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; | |
673 | if (time_before(now, holdtime)) | |
674 | delay = holdtime - now; | |
675 | set_bit(delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE, &gl->gl_flags); | |
676 | } | |
677 | run_queue(gl, 0); | |
c4f68a13 | 678 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
679 | if (!delay || |
680 | queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
681 | gfs2_glock_put(gl); | |
c4f68a13 BM |
682 | } |
683 | ||
da755fdb SW |
684 | static int gfs2_lm_get_lock(struct gfs2_sbd *sdp, struct lm_lockname *name, |
685 | void **lockp) | |
686 | { | |
687 | int error = -EIO; | |
048bca22 SW |
688 | if (!sdp->sd_lockstruct.ls_ops->lm_get_lock) |
689 | return 0; | |
da755fdb SW |
690 | if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
691 | error = sdp->sd_lockstruct.ls_ops->lm_get_lock( | |
692 | sdp->sd_lockstruct.ls_lockspace, name, lockp); | |
693 | return error; | |
694 | } | |
695 | ||
b3b94faa DT |
696 | /** |
697 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
698 | * @sdp: The GFS2 superblock | |
699 | * @number: the lock number | |
700 | * @glops: The glock_operations to use | |
701 | * @create: If 0, don't create the glock if it doesn't exist | |
702 | * @glp: the glock is returned here | |
703 | * | |
704 | * This does not lock a glock, just finds/creates structures for one. | |
705 | * | |
706 | * Returns: errno | |
707 | */ | |
708 | ||
cd915493 | 709 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 | 710 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
711 | struct gfs2_glock **glp) |
712 | { | |
37b2fa6a | 713 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
b3b94faa | 714 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 715 | unsigned int hash = gl_hash(sdp, &name); |
b3b94faa DT |
716 | int error; |
717 | ||
087efdd3 | 718 | read_lock(gl_lock_addr(hash)); |
37b2fa6a | 719 | gl = search_bucket(hash, sdp, &name); |
087efdd3 | 720 | read_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
721 | |
722 | if (gl || !create) { | |
723 | *glp = gl; | |
724 | return 0; | |
725 | } | |
726 | ||
727 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); | |
728 | if (!gl) | |
729 | return -ENOMEM; | |
730 | ||
ec45d9f5 | 731 | gl->gl_flags = 0; |
b3b94faa | 732 | gl->gl_name = name; |
16feb9fe | 733 | atomic_set(&gl->gl_ref, 1); |
b3b94faa | 734 | gl->gl_state = LM_ST_UNLOCKED; |
6802e340 | 735 | gl->gl_target = LM_ST_UNLOCKED; |
c4f68a13 | 736 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
37b2fa6a | 737 | gl->gl_hash = hash; |
b3b94faa | 738 | gl->gl_ops = glops; |
ec45d9f5 | 739 | gl->gl_stamp = jiffies; |
c4f68a13 | 740 | gl->gl_tchange = jiffies; |
ec45d9f5 | 741 | gl->gl_object = NULL; |
b3b94faa | 742 | gl->gl_sbd = sdp; |
ec45d9f5 | 743 | gl->gl_aspace = NULL; |
c4f68a13 | 744 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
b3b94faa DT |
745 | |
746 | /* If this glock protects actual on-disk data or metadata blocks, | |
747 | create a VFS inode to manage the pages/buffers holding them. */ | |
50299965 | 748 | if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) { |
b3b94faa DT |
749 | gl->gl_aspace = gfs2_aspace_get(sdp); |
750 | if (!gl->gl_aspace) { | |
751 | error = -ENOMEM; | |
752 | goto fail; | |
753 | } | |
754 | } | |
755 | ||
756 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
757 | if (error) | |
758 | goto fail_aspace; | |
759 | ||
087efdd3 | 760 | write_lock(gl_lock_addr(hash)); |
37b2fa6a | 761 | tmp = search_bucket(hash, sdp, &name); |
b3b94faa | 762 | if (tmp) { |
087efdd3 | 763 | write_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
764 | glock_free(gl); |
765 | gl = tmp; | |
766 | } else { | |
b6397893 | 767 | hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list); |
087efdd3 | 768 | write_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
769 | } |
770 | ||
771 | *glp = gl; | |
772 | ||
773 | return 0; | |
774 | ||
ec45d9f5 | 775 | fail_aspace: |
b3b94faa DT |
776 | if (gl->gl_aspace) |
777 | gfs2_aspace_put(gl->gl_aspace); | |
ec45d9f5 | 778 | fail: |
907b9bce | 779 | kmem_cache_free(gfs2_glock_cachep, gl); |
b3b94faa DT |
780 | return error; |
781 | } | |
782 | ||
783 | /** | |
784 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
785 | * @gl: the glock | |
786 | * @state: the state we're requesting | |
787 | * @flags: the modifier flags | |
788 | * @gh: the holder structure | |
789 | * | |
790 | */ | |
791 | ||
190562bd | 792 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
793 | struct gfs2_holder *gh) |
794 | { | |
795 | INIT_LIST_HEAD(&gh->gh_list); | |
796 | gh->gh_gl = gl; | |
d0dc80db | 797 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b1e058da | 798 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
799 | gh->gh_state = state; |
800 | gh->gh_flags = flags; | |
801 | gh->gh_error = 0; | |
802 | gh->gh_iflags = 0; | |
b3b94faa DT |
803 | gfs2_glock_hold(gl); |
804 | } | |
805 | ||
806 | /** | |
807 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
808 | * @state: the state we're requesting | |
809 | * @flags: the modifier flags | |
810 | * @gh: the holder structure | |
811 | * | |
812 | * Don't mess with the glock. | |
813 | * | |
814 | */ | |
815 | ||
190562bd | 816 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
817 | { |
818 | gh->gh_state = state; | |
579b78a4 | 819 | gh->gh_flags = flags; |
3b8249f6 | 820 | gh->gh_iflags = 0; |
d0dc80db | 821 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
822 | } |
823 | ||
824 | /** | |
825 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
826 | * @gh: the holder structure | |
827 | * | |
828 | */ | |
829 | ||
830 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
831 | { | |
b1e058da | 832 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
833 | gfs2_glock_put(gh->gh_gl); |
834 | gh->gh_gl = NULL; | |
d0dc80db | 835 | gh->gh_ip = 0; |
b3b94faa DT |
836 | } |
837 | ||
d93cfa98 | 838 | static int just_schedule(void *word) |
fee852e3 SW |
839 | { |
840 | schedule(); | |
841 | return 0; | |
842 | } | |
843 | ||
6802e340 | 844 | static void wait_on_holder(struct gfs2_holder *gh) |
da755fdb | 845 | { |
6802e340 SW |
846 | might_sleep(); |
847 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, just_schedule, TASK_UNINTERRUPTIBLE); | |
da755fdb SW |
848 | } |
849 | ||
6802e340 | 850 | static void wait_on_demote(struct gfs2_glock *gl) |
b3b94faa | 851 | { |
6802e340 SW |
852 | might_sleep(); |
853 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, just_schedule, TASK_UNINTERRUPTIBLE); | |
b3b94faa DT |
854 | } |
855 | ||
856 | /** | |
6802e340 SW |
857 | * handle_callback - process a demote request |
858 | * @gl: the glock | |
859 | * @state: the state the caller wants us to change to | |
b3b94faa | 860 | * |
6802e340 SW |
861 | * There are only two requests that we are going to see in actual |
862 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
863 | */ |
864 | ||
6802e340 | 865 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
97cc1025 | 866 | unsigned long delay) |
b3b94faa | 867 | { |
6802e340 | 868 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 869 | |
6802e340 SW |
870 | set_bit(bit, &gl->gl_flags); |
871 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
872 | gl->gl_demote_state = state; | |
873 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
874 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
875 | gl->gl_demote_state != state) { | |
876 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 877 | } |
b3b94faa DT |
878 | } |
879 | ||
880 | /** | |
6802e340 | 881 | * gfs2_glock_wait - wait on a glock acquisition |
b3b94faa DT |
882 | * @gh: the glock holder |
883 | * | |
884 | * Returns: 0 on success | |
885 | */ | |
886 | ||
6802e340 | 887 | int gfs2_glock_wait(struct gfs2_holder *gh) |
b3b94faa | 888 | { |
fee852e3 | 889 | wait_on_holder(gh); |
b3b94faa DT |
890 | return gh->gh_error; |
891 | } | |
892 | ||
6802e340 | 893 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 RP |
894 | { |
895 | va_list args; | |
896 | ||
897 | va_start(args, fmt); | |
6802e340 SW |
898 | if (seq) { |
899 | struct gfs2_glock_iter *gi = seq->private; | |
7c52b166 | 900 | vsprintf(gi->string, fmt, args); |
6802e340 SW |
901 | seq_printf(seq, gi->string); |
902 | } else { | |
903 | printk(KERN_ERR " "); | |
7c52b166 | 904 | vprintk(fmt, args); |
6802e340 | 905 | } |
7c52b166 RP |
906 | va_end(args); |
907 | } | |
908 | ||
b3b94faa DT |
909 | /** |
910 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
911 | * @gh: the holder structure to add | |
912 | * | |
6802e340 SW |
913 | * Eventually we should move the recursive locking trap to a |
914 | * debugging option or something like that. This is the fast | |
915 | * path and needs to have the minimum number of distractions. | |
916 | * | |
b3b94faa DT |
917 | */ |
918 | ||
6802e340 | 919 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
920 | __releases(&gl->gl_spin) |
921 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
922 | { |
923 | struct gfs2_glock *gl = gh->gh_gl; | |
6802e340 SW |
924 | struct gfs2_sbd *sdp = gl->gl_sbd; |
925 | struct list_head *insert_pt = NULL; | |
926 | struct gfs2_holder *gh2; | |
927 | int try_lock = 0; | |
b3b94faa | 928 | |
b1e058da | 929 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
930 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
931 | BUG(); | |
190562bd | 932 | |
6802e340 SW |
933 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
934 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
935 | try_lock = 1; | |
936 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) | |
937 | goto fail; | |
938 | } | |
939 | ||
940 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
941 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
942 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
943 | goto trap_recursive; | |
944 | if (try_lock && | |
945 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) && | |
946 | !may_grant(gl, gh)) { | |
947 | fail: | |
948 | gh->gh_error = GLR_TRYFAILED; | |
949 | gfs2_holder_wake(gh); | |
950 | return; | |
b4c20166 | 951 | } |
6802e340 SW |
952 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
953 | continue; | |
954 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
955 | insert_pt = &gh2->gh_list; | |
956 | } | |
957 | if (likely(insert_pt == NULL)) { | |
958 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
959 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
960 | goto do_cancel; | |
961 | return; | |
962 | } | |
963 | list_add_tail(&gh->gh_list, insert_pt); | |
964 | do_cancel: | |
965 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
966 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
967 | spin_unlock(&gl->gl_spin); | |
048bca22 SW |
968 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
969 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl->gl_lock); | |
6802e340 | 970 | spin_lock(&gl->gl_spin); |
b3b94faa | 971 | } |
6802e340 | 972 | return; |
b3b94faa | 973 | |
6802e340 SW |
974 | trap_recursive: |
975 | print_symbol(KERN_ERR "original: %s\n", gh2->gh_ip); | |
976 | printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid)); | |
977 | printk(KERN_ERR "lock type: %d req lock state : %d\n", | |
978 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); | |
979 | print_symbol(KERN_ERR "new: %s\n", gh->gh_ip); | |
980 | printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid)); | |
981 | printk(KERN_ERR "lock type: %d req lock state : %d\n", | |
982 | gh->gh_gl->gl_name.ln_type, gh->gh_state); | |
983 | __dump_glock(NULL, gl); | |
984 | BUG(); | |
b3b94faa DT |
985 | } |
986 | ||
987 | /** | |
988 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
989 | * @gh: the holder structure | |
990 | * | |
991 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
992 | * | |
993 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
994 | */ | |
995 | ||
996 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
997 | { | |
998 | struct gfs2_glock *gl = gh->gh_gl; | |
999 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1000 | int error = 0; | |
1001 | ||
6802e340 | 1002 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1003 | return -EIO; |
b3b94faa | 1004 | |
b3b94faa DT |
1005 | spin_lock(&gl->gl_spin); |
1006 | add_to_queue(gh); | |
6802e340 | 1007 | run_queue(gl, 1); |
b3b94faa DT |
1008 | spin_unlock(&gl->gl_spin); |
1009 | ||
6802e340 SW |
1010 | if (!(gh->gh_flags & GL_ASYNC)) |
1011 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1012 | |
b3b94faa DT |
1013 | return error; |
1014 | } | |
1015 | ||
1016 | /** | |
1017 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1018 | * @gh: the holder | |
1019 | * | |
1020 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1021 | */ | |
1022 | ||
1023 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1024 | { | |
6802e340 | 1025 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1026 | } |
1027 | ||
1028 | /** | |
1029 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1030 | * @gh: the glock holder | |
1031 | * | |
1032 | */ | |
1033 | ||
1034 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1035 | { | |
1036 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1037 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1038 | unsigned delay = 0; |
6802e340 | 1039 | int fast_path = 0; |
b3b94faa | 1040 | |
6802e340 | 1041 | spin_lock(&gl->gl_spin); |
b3b94faa | 1042 | if (gh->gh_flags & GL_NOCACHE) |
97cc1025 | 1043 | handle_callback(gl, LM_ST_UNLOCKED, 0); |
b3b94faa | 1044 | |
b3b94faa | 1045 | list_del_init(&gh->gh_list); |
6802e340 | 1046 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1047 | if (glops->go_unlock) { |
6802e340 | 1048 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1049 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1050 | glops->go_unlock(gh); |
3042a2cc | 1051 | spin_lock(&gl->gl_spin); |
6802e340 | 1052 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1053 | } |
3b8249f6 | 1054 | gl->gl_stamp = jiffies; |
6802e340 SW |
1055 | if (list_empty(&gl->gl_holders) && |
1056 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1057 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1058 | fast_path = 1; | |
b3b94faa | 1059 | } |
b3b94faa | 1060 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1061 | if (likely(fast_path)) |
1062 | return; | |
c4f68a13 BM |
1063 | |
1064 | gfs2_glock_hold(gl); | |
1065 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1066 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1067 | delay = gl->gl_ops->go_min_hold_time; | |
1068 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
1069 | gfs2_glock_put(gl); | |
b3b94faa DT |
1070 | } |
1071 | ||
d93cfa98 AD |
1072 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1073 | { | |
1074 | struct gfs2_glock *gl = gh->gh_gl; | |
1075 | gfs2_glock_dq(gh); | |
1076 | wait_on_demote(gl); | |
1077 | } | |
1078 | ||
b3b94faa DT |
1079 | /** |
1080 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1081 | * @gh: the holder structure | |
1082 | * | |
1083 | */ | |
1084 | ||
1085 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1086 | { | |
1087 | gfs2_glock_dq(gh); | |
1088 | gfs2_holder_uninit(gh); | |
1089 | } | |
1090 | ||
1091 | /** | |
1092 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1093 | * @sdp: the filesystem | |
1094 | * @number: the lock number | |
1095 | * @glops: the glock operations for the type of glock | |
1096 | * @state: the state to acquire the glock in | |
1097 | * @flags: modifier flags for the aquisition | |
1098 | * @gh: the struct gfs2_holder | |
1099 | * | |
1100 | * Returns: errno | |
1101 | */ | |
1102 | ||
cd915493 | 1103 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1104 | const struct gfs2_glock_operations *glops, |
1105 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1106 | { |
1107 | struct gfs2_glock *gl; | |
1108 | int error; | |
1109 | ||
1110 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1111 | if (!error) { | |
1112 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1113 | gfs2_glock_put(gl); | |
1114 | } | |
1115 | ||
1116 | return error; | |
1117 | } | |
1118 | ||
1119 | /** | |
1120 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1121 | * @arg_a: the first structure | |
1122 | * @arg_b: the second structure | |
1123 | * | |
1124 | */ | |
1125 | ||
1126 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1127 | { | |
a5e08a9e SW |
1128 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1129 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1130 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1131 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1132 | |
1133 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1134 | return 1; |
1135 | if (a->ln_number < b->ln_number) | |
1136 | return -1; | |
1c0f4872 | 1137 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1138 | return 0; |
b3b94faa DT |
1139 | } |
1140 | ||
1141 | /** | |
1142 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1143 | * @num_gh: the number of structures | |
1144 | * @ghs: an array of struct gfs2_holder structures | |
1145 | * | |
1146 | * Returns: 0 on success (all glocks acquired), | |
1147 | * errno on failure (no glocks acquired) | |
1148 | */ | |
1149 | ||
1150 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1151 | struct gfs2_holder **p) | |
1152 | { | |
1153 | unsigned int x; | |
1154 | int error = 0; | |
1155 | ||
1156 | for (x = 0; x < num_gh; x++) | |
1157 | p[x] = &ghs[x]; | |
1158 | ||
1159 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1160 | ||
1161 | for (x = 0; x < num_gh; x++) { | |
1162 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1163 | ||
1164 | error = gfs2_glock_nq(p[x]); | |
1165 | if (error) { | |
1166 | while (x--) | |
1167 | gfs2_glock_dq(p[x]); | |
1168 | break; | |
1169 | } | |
1170 | } | |
1171 | ||
1172 | return error; | |
1173 | } | |
1174 | ||
1175 | /** | |
1176 | * gfs2_glock_nq_m - acquire multiple glocks | |
1177 | * @num_gh: the number of structures | |
1178 | * @ghs: an array of struct gfs2_holder structures | |
1179 | * | |
b3b94faa DT |
1180 | * |
1181 | * Returns: 0 on success (all glocks acquired), | |
1182 | * errno on failure (no glocks acquired) | |
1183 | */ | |
1184 | ||
1185 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1186 | { | |
eaf5bd3c SW |
1187 | struct gfs2_holder *tmp[4]; |
1188 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1189 | int error = 0; |
1190 | ||
eaf5bd3c SW |
1191 | switch(num_gh) { |
1192 | case 0: | |
b3b94faa | 1193 | return 0; |
eaf5bd3c | 1194 | case 1: |
b3b94faa DT |
1195 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1196 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1197 | default: |
1198 | if (num_gh <= 4) | |
b3b94faa | 1199 | break; |
eaf5bd3c SW |
1200 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1201 | if (!pph) | |
1202 | return -ENOMEM; | |
b3b94faa DT |
1203 | } |
1204 | ||
eaf5bd3c | 1205 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1206 | |
eaf5bd3c SW |
1207 | if (pph != tmp) |
1208 | kfree(pph); | |
b3b94faa DT |
1209 | |
1210 | return error; | |
1211 | } | |
1212 | ||
1213 | /** | |
1214 | * gfs2_glock_dq_m - release multiple glocks | |
1215 | * @num_gh: the number of structures | |
1216 | * @ghs: an array of struct gfs2_holder structures | |
1217 | * | |
1218 | */ | |
1219 | ||
1220 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1221 | { | |
1222 | unsigned int x; | |
1223 | ||
1224 | for (x = 0; x < num_gh; x++) | |
1225 | gfs2_glock_dq(&ghs[x]); | |
1226 | } | |
1227 | ||
1228 | /** | |
1229 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1230 | * @num_gh: the number of structures | |
1231 | * @ghs: an array of struct gfs2_holder structures | |
1232 | * | |
1233 | */ | |
1234 | ||
1235 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1236 | { | |
1237 | unsigned int x; | |
1238 | ||
1239 | for (x = 0; x < num_gh; x++) | |
1240 | gfs2_glock_dq_uninit(&ghs[x]); | |
1241 | } | |
1242 | ||
da755fdb SW |
1243 | static int gfs2_lm_hold_lvb(struct gfs2_sbd *sdp, void *lock, char **lvbp) |
1244 | { | |
1245 | int error = -EIO; | |
048bca22 SW |
1246 | if (!sdp->sd_lockstruct.ls_ops->lm_hold_lvb) |
1247 | return 0; | |
da755fdb SW |
1248 | if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
1249 | error = sdp->sd_lockstruct.ls_ops->lm_hold_lvb(lock, lvbp); | |
1250 | return error; | |
1251 | } | |
1252 | ||
b3b94faa DT |
1253 | /** |
1254 | * gfs2_lvb_hold - attach a LVB from a glock | |
1255 | * @gl: The glock in question | |
1256 | * | |
1257 | */ | |
1258 | ||
1259 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1260 | { | |
1261 | int error; | |
1262 | ||
b3b94faa DT |
1263 | if (!atomic_read(&gl->gl_lvb_count)) { |
1264 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
6802e340 | 1265 | if (error) |
b3b94faa | 1266 | return error; |
b3b94faa DT |
1267 | gfs2_glock_hold(gl); |
1268 | } | |
1269 | atomic_inc(&gl->gl_lvb_count); | |
1270 | ||
b3b94faa DT |
1271 | return 0; |
1272 | } | |
1273 | ||
1274 | /** | |
1275 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1276 | * @gl: The glock in question | |
1277 | * | |
1278 | */ | |
1279 | ||
1280 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1281 | { | |
da755fdb SW |
1282 | struct gfs2_sbd *sdp = gl->gl_sbd; |
1283 | ||
b3b94faa | 1284 | gfs2_glock_hold(gl); |
b3b94faa DT |
1285 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); |
1286 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
048bca22 | 1287 | if (sdp->sd_lockstruct.ls_ops->lm_unhold_lvb) |
da755fdb | 1288 | sdp->sd_lockstruct.ls_ops->lm_unhold_lvb(gl->gl_lock, gl->gl_lvb); |
b3b94faa DT |
1289 | gl->gl_lvb = NULL; |
1290 | gfs2_glock_put(gl); | |
1291 | } | |
b3b94faa DT |
1292 | gfs2_glock_put(gl); |
1293 | } | |
1294 | ||
b3b94faa DT |
1295 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, |
1296 | unsigned int state) | |
1297 | { | |
1298 | struct gfs2_glock *gl; | |
c4f68a13 BM |
1299 | unsigned long delay = 0; |
1300 | unsigned long holdtime; | |
1301 | unsigned long now = jiffies; | |
b3b94faa DT |
1302 | |
1303 | gl = gfs2_glock_find(sdp, name); | |
1304 | if (!gl) | |
1305 | return; | |
1306 | ||
c4f68a13 BM |
1307 | holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; |
1308 | if (time_before(now, holdtime)) | |
1309 | delay = holdtime - now; | |
dff52574 SW |
1310 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) |
1311 | delay = gl->gl_ops->go_min_hold_time; | |
b3b94faa | 1312 | |
6802e340 | 1313 | spin_lock(&gl->gl_spin); |
97cc1025 | 1314 | handle_callback(gl, state, delay); |
6802e340 | 1315 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1316 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1317 | gfs2_glock_put(gl); | |
b3b94faa DT |
1318 | } |
1319 | ||
2bfb6449 SW |
1320 | static void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid) |
1321 | { | |
1322 | struct gfs2_jdesc *jd; | |
1323 | ||
1324 | spin_lock(&sdp->sd_jindex_spin); | |
1325 | list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) { | |
1326 | if (jd->jd_jid != jid) | |
1327 | continue; | |
1328 | jd->jd_dirty = 1; | |
1329 | break; | |
1330 | } | |
1331 | spin_unlock(&sdp->sd_jindex_spin); | |
1332 | } | |
1333 | ||
b3b94faa DT |
1334 | /** |
1335 | * gfs2_glock_cb - Callback used by locking module | |
1c089c32 | 1336 | * @sdp: Pointer to the superblock |
b3b94faa DT |
1337 | * @type: Type of callback |
1338 | * @data: Type dependent data pointer | |
1339 | * | |
1340 | * Called by the locking module when it wants to tell us something. | |
1341 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1342 | * a journal from another client needs to be recovered. | |
1343 | */ | |
1344 | ||
9b47c11d | 1345 | void gfs2_glock_cb(void *cb_data, unsigned int type, void *data) |
b3b94faa | 1346 | { |
9b47c11d | 1347 | struct gfs2_sbd *sdp = cb_data; |
b3b94faa | 1348 | |
b3b94faa DT |
1349 | switch (type) { |
1350 | case LM_CB_NEED_E: | |
e7f5c01c | 1351 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
b3b94faa DT |
1352 | return; |
1353 | ||
1354 | case LM_CB_NEED_D: | |
e7f5c01c | 1355 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
b3b94faa DT |
1356 | return; |
1357 | ||
1358 | case LM_CB_NEED_S: | |
e7f5c01c | 1359 | blocking_cb(sdp, data, LM_ST_SHARED); |
b3b94faa DT |
1360 | return; |
1361 | ||
1362 | case LM_CB_ASYNC: { | |
e7f5c01c | 1363 | struct lm_async_cb *async = data; |
b3b94faa DT |
1364 | struct gfs2_glock *gl; |
1365 | ||
61be084e | 1366 | down_read(&gfs2_umount_flush_sem); |
b3b94faa DT |
1367 | gl = gfs2_glock_find(sdp, &async->lc_name); |
1368 | if (gfs2_assert_warn(sdp, gl)) | |
1369 | return; | |
6802e340 SW |
1370 | gl->gl_reply = async->lc_ret; |
1371 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); | |
c4f68a13 BM |
1372 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1373 | gfs2_glock_put(gl); | |
61be084e | 1374 | up_read(&gfs2_umount_flush_sem); |
b3b94faa DT |
1375 | return; |
1376 | } | |
1377 | ||
1378 | case LM_CB_NEED_RECOVERY: | |
1379 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1380 | if (sdp->sd_recoverd_process) | |
1381 | wake_up_process(sdp->sd_recoverd_process); | |
1382 | return; | |
1383 | ||
b3b94faa DT |
1384 | default: |
1385 | gfs2_assert_warn(sdp, 0); | |
1386 | return; | |
1387 | } | |
1388 | } | |
1389 | ||
b3b94faa DT |
1390 | /** |
1391 | * demote_ok - Check to see if it's ok to unlock a glock | |
1392 | * @gl: the glock | |
1393 | * | |
1394 | * Returns: 1 if it's ok | |
1395 | */ | |
1396 | ||
97cc1025 | 1397 | static int demote_ok(const struct gfs2_glock *gl) |
b3b94faa | 1398 | { |
8fb4b536 | 1399 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa | 1400 | |
97cc1025 SW |
1401 | if (gl->gl_state == LM_ST_UNLOCKED) |
1402 | return 0; | |
1403 | if (!list_empty(&gl->gl_holders)) | |
1404 | return 0; | |
1405 | if (glops->go_demote_ok) | |
1406 | return glops->go_demote_ok(gl); | |
1407 | return 1; | |
b3b94faa DT |
1408 | } |
1409 | ||
b3b94faa | 1410 | |
97cc1025 | 1411 | static int gfs2_shrink_glock_memory(int nr, gfp_t gfp_mask) |
b3b94faa DT |
1412 | { |
1413 | struct gfs2_glock *gl; | |
97cc1025 SW |
1414 | int may_demote; |
1415 | int nr_skipped = 0; | |
1416 | int got_ref = 0; | |
1417 | LIST_HEAD(skipped); | |
b3b94faa | 1418 | |
97cc1025 SW |
1419 | if (nr == 0) |
1420 | goto out; | |
b3b94faa | 1421 | |
97cc1025 SW |
1422 | if (!(gfp_mask & __GFP_FS)) |
1423 | return -1; | |
b3b94faa | 1424 | |
97cc1025 SW |
1425 | spin_lock(&lru_lock); |
1426 | while(nr && !list_empty(&lru_list)) { | |
1427 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); | |
1428 | list_del_init(&gl->gl_lru); | |
1429 | atomic_dec(&lru_count); | |
1430 | ||
1431 | /* Test for being demotable */ | |
1432 | if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { | |
1433 | gfs2_glock_hold(gl); | |
1434 | got_ref = 1; | |
1435 | spin_unlock(&lru_lock); | |
1436 | spin_lock(&gl->gl_spin); | |
1437 | may_demote = demote_ok(gl); | |
1438 | spin_unlock(&gl->gl_spin); | |
1439 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1440 | if (may_demote) { | |
1441 | handle_callback(gl, LM_ST_UNLOCKED, 0); | |
1442 | nr--; | |
1443 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1444 | gfs2_glock_put(gl); | |
1445 | } | |
1446 | spin_lock(&lru_lock); | |
1447 | if (may_demote) | |
1448 | continue; | |
1449 | } | |
1450 | if (list_empty(&gl->gl_lru) && | |
1451 | (atomic_read(&gl->gl_ref) <= (2 + got_ref))) { | |
1452 | nr_skipped++; | |
1453 | list_add(&gl->gl_lru, &skipped); | |
1454 | } | |
1455 | if (got_ref) { | |
1456 | spin_unlock(&lru_lock); | |
1457 | gfs2_glock_put(gl); | |
1458 | spin_lock(&lru_lock); | |
1459 | got_ref = 0; | |
1460 | } | |
b3b94faa | 1461 | } |
97cc1025 SW |
1462 | list_splice(&skipped, &lru_list); |
1463 | atomic_add(nr_skipped, &lru_count); | |
1464 | spin_unlock(&lru_lock); | |
1465 | out: | |
1466 | return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure; | |
b3b94faa DT |
1467 | } |
1468 | ||
97cc1025 SW |
1469 | static struct shrinker glock_shrinker = { |
1470 | .shrink = gfs2_shrink_glock_memory, | |
1471 | .seeks = DEFAULT_SEEKS, | |
1472 | }; | |
1473 | ||
b3b94faa DT |
1474 | /** |
1475 | * examine_bucket - Call a function for glock in a hash bucket | |
1476 | * @examiner: the function | |
1477 | * @sdp: the filesystem | |
1478 | * @bucket: the bucket | |
1479 | * | |
1480 | * Returns: 1 if the bucket has entries | |
1481 | */ | |
1482 | ||
1483 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
37b2fa6a | 1484 | unsigned int hash) |
b3b94faa | 1485 | { |
24264434 SW |
1486 | struct gfs2_glock *gl, *prev = NULL; |
1487 | int has_entries = 0; | |
b6397893 | 1488 | struct hlist_head *head = &gl_hash_table[hash].hb_list; |
b3b94faa | 1489 | |
24264434 | 1490 | read_lock(gl_lock_addr(hash)); |
b6397893 SW |
1491 | /* Can't use hlist_for_each_entry - don't want prefetch here */ |
1492 | if (hlist_empty(head)) | |
24264434 | 1493 | goto out; |
b6397893 SW |
1494 | gl = list_entry(head->first, struct gfs2_glock, gl_list); |
1495 | while(1) { | |
8fbbfd21 | 1496 | if (!sdp || gl->gl_sbd == sdp) { |
b3b94faa | 1497 | gfs2_glock_hold(gl); |
24264434 SW |
1498 | read_unlock(gl_lock_addr(hash)); |
1499 | if (prev) | |
1500 | gfs2_glock_put(prev); | |
1501 | prev = gl; | |
1502 | examiner(gl); | |
a8336344 | 1503 | has_entries = 1; |
24264434 | 1504 | read_lock(gl_lock_addr(hash)); |
b3b94faa | 1505 | } |
b6397893 SW |
1506 | if (gl->gl_list.next == NULL) |
1507 | break; | |
24264434 | 1508 | gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list); |
b3b94faa | 1509 | } |
24264434 SW |
1510 | out: |
1511 | read_unlock(gl_lock_addr(hash)); | |
1512 | if (prev) | |
1513 | gfs2_glock_put(prev); | |
8fbbfd21 | 1514 | cond_resched(); |
24264434 | 1515 | return has_entries; |
b3b94faa DT |
1516 | } |
1517 | ||
b3b94faa DT |
1518 | /** |
1519 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1520 | * @gl: the glock to look at | |
1521 | * | |
1522 | */ | |
1523 | ||
1524 | static void clear_glock(struct gfs2_glock *gl) | |
1525 | { | |
97cc1025 SW |
1526 | spin_lock(&lru_lock); |
1527 | if (!list_empty(&gl->gl_lru)) { | |
1528 | list_del_init(&gl->gl_lru); | |
1529 | atomic_dec(&lru_count); | |
b3b94faa | 1530 | } |
97cc1025 | 1531 | spin_unlock(&lru_lock); |
b3b94faa | 1532 | |
6802e340 SW |
1533 | spin_lock(&gl->gl_spin); |
1534 | if (find_first_holder(gl) == NULL && gl->gl_state != LM_ST_UNLOCKED) | |
97cc1025 | 1535 | handle_callback(gl, LM_ST_UNLOCKED, 0); |
6802e340 SW |
1536 | spin_unlock(&gl->gl_spin); |
1537 | gfs2_glock_hold(gl); | |
1538 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1539 | gfs2_glock_put(gl); | |
b3b94faa DT |
1540 | } |
1541 | ||
1542 | /** | |
1543 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1544 | * @sdp: the filesystem | |
1545 | * @wait: wait until it's all gone | |
1546 | * | |
1bdad606 | 1547 | * Called when unmounting the filesystem. |
b3b94faa DT |
1548 | */ |
1549 | ||
fefc03bf | 1550 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa DT |
1551 | { |
1552 | unsigned long t; | |
1553 | unsigned int x; | |
1554 | int cont; | |
1555 | ||
1556 | t = jiffies; | |
1557 | ||
1558 | for (;;) { | |
1559 | cont = 0; | |
24264434 | 1560 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { |
907b9bce | 1561 | if (examine_bucket(clear_glock, sdp, x)) |
b3b94faa | 1562 | cont = 1; |
24264434 | 1563 | } |
b3b94faa | 1564 | |
1bdad606 | 1565 | if (!cont) |
b3b94faa DT |
1566 | break; |
1567 | ||
1568 | if (time_after_eq(jiffies, | |
1569 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
1570 | fs_warn(sdp, "Unmount seems to be stalled. " | |
1571 | "Dumping lock state...\n"); | |
1572 | gfs2_dump_lockstate(sdp); | |
1573 | t = jiffies; | |
1574 | } | |
1575 | ||
61be084e | 1576 | down_write(&gfs2_umount_flush_sem); |
b3b94faa | 1577 | invalidate_inodes(sdp->sd_vfs); |
61be084e | 1578 | up_write(&gfs2_umount_flush_sem); |
fd88de56 | 1579 | msleep(10); |
b3b94faa DT |
1580 | } |
1581 | } | |
1582 | ||
813e0c46 SW |
1583 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1584 | { | |
1585 | struct gfs2_glock *gl = ip->i_gl; | |
1586 | int ret; | |
1587 | ||
1588 | ret = gfs2_truncatei_resume(ip); | |
1589 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); | |
1590 | ||
1591 | spin_lock(&gl->gl_spin); | |
1592 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1593 | run_queue(gl, 1); | |
1594 | spin_unlock(&gl->gl_spin); | |
1595 | } | |
1596 | ||
6802e340 | 1597 | static const char *state2str(unsigned state) |
04b933f2 | 1598 | { |
6802e340 SW |
1599 | switch(state) { |
1600 | case LM_ST_UNLOCKED: | |
1601 | return "UN"; | |
1602 | case LM_ST_SHARED: | |
1603 | return "SH"; | |
1604 | case LM_ST_DEFERRED: | |
1605 | return "DF"; | |
1606 | case LM_ST_EXCLUSIVE: | |
1607 | return "EX"; | |
1608 | } | |
1609 | return "??"; | |
1610 | } | |
1611 | ||
1612 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1613 | { | |
1614 | char *p = buf; | |
1615 | if (flags & LM_FLAG_TRY) | |
1616 | *p++ = 't'; | |
1617 | if (flags & LM_FLAG_TRY_1CB) | |
1618 | *p++ = 'T'; | |
1619 | if (flags & LM_FLAG_NOEXP) | |
1620 | *p++ = 'e'; | |
1621 | if (flags & LM_FLAG_ANY) | |
1622 | *p++ = 'a'; | |
1623 | if (flags & LM_FLAG_PRIORITY) | |
1624 | *p++ = 'p'; | |
1625 | if (flags & GL_ASYNC) | |
1626 | *p++ = 'a'; | |
1627 | if (flags & GL_EXACT) | |
1628 | *p++ = 'E'; | |
6802e340 SW |
1629 | if (flags & GL_NOCACHE) |
1630 | *p++ = 'c'; | |
1631 | if (test_bit(HIF_HOLDER, &iflags)) | |
1632 | *p++ = 'H'; | |
1633 | if (test_bit(HIF_WAIT, &iflags)) | |
1634 | *p++ = 'W'; | |
1635 | if (test_bit(HIF_FIRST, &iflags)) | |
1636 | *p++ = 'F'; | |
1637 | *p = 0; | |
1638 | return buf; | |
04b933f2 RP |
1639 | } |
1640 | ||
b3b94faa DT |
1641 | /** |
1642 | * dump_holder - print information about a glock holder | |
6802e340 | 1643 | * @seq: the seq_file struct |
b3b94faa DT |
1644 | * @gh: the glock holder |
1645 | * | |
1646 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1647 | */ | |
1648 | ||
6802e340 | 1649 | static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1650 | { |
6802e340 SW |
1651 | struct task_struct *gh_owner = NULL; |
1652 | char buffer[KSYM_SYMBOL_LEN]; | |
1653 | char flags_buf[32]; | |
b3b94faa | 1654 | |
6802e340 SW |
1655 | sprint_symbol(buffer, gh->gh_ip); |
1656 | if (gh->gh_owner_pid) | |
b1e058da | 1657 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
6802e340 SW |
1658 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %s\n", |
1659 | state2str(gh->gh_state), | |
1660 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1661 | gh->gh_error, | |
1662 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1663 | gh_owner ? gh_owner->comm : "(ended)", buffer); | |
7c52b166 | 1664 | return 0; |
b3b94faa DT |
1665 | } |
1666 | ||
6802e340 SW |
1667 | static const char *gflags2str(char *buf, const unsigned long *gflags) |
1668 | { | |
1669 | char *p = buf; | |
1670 | if (test_bit(GLF_LOCK, gflags)) | |
1671 | *p++ = 'l'; | |
6802e340 SW |
1672 | if (test_bit(GLF_DEMOTE, gflags)) |
1673 | *p++ = 'D'; | |
1674 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1675 | *p++ = 'd'; | |
1676 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1677 | *p++ = 'p'; | |
1678 | if (test_bit(GLF_DIRTY, gflags)) | |
1679 | *p++ = 'y'; | |
1680 | if (test_bit(GLF_LFLUSH, gflags)) | |
1681 | *p++ = 'f'; | |
1682 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1683 | *p++ = 'i'; | |
1684 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1685 | *p++ = 'r'; | |
1686 | *p = 0; | |
1687 | return buf; | |
b3b94faa DT |
1688 | } |
1689 | ||
1690 | /** | |
6802e340 SW |
1691 | * __dump_glock - print information about a glock |
1692 | * @seq: The seq_file struct | |
b3b94faa | 1693 | * @gl: the glock |
6802e340 SW |
1694 | * |
1695 | * The file format is as follows: | |
1696 | * One line per object, capital letters are used to indicate objects | |
1697 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1698 | * other objects are indented by a single space and follow the glock to | |
1699 | * which they are related. Fields are indicated by lower case letters | |
1700 | * followed by a colon and the field value, except for strings which are in | |
1701 | * [] so that its possible to see if they are composed of spaces for | |
1702 | * example. The field's are n = number (id of the object), f = flags, | |
1703 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa DT |
1704 | * |
1705 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1706 | */ | |
1707 | ||
6802e340 | 1708 | static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1709 | { |
6802e340 SW |
1710 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1711 | unsigned long long dtime; | |
1712 | const struct gfs2_holder *gh; | |
1713 | char gflags_buf[32]; | |
1714 | int error = 0; | |
b3b94faa | 1715 | |
6802e340 SW |
1716 | dtime = jiffies - gl->gl_demote_time; |
1717 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1718 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1719 | dtime = 0; | |
1720 | gfs2_print_dbg(seq, "G: s:%s n:%u/%llu f:%s t:%s d:%s/%llu l:%d a:%d r:%d\n", | |
1721 | state2str(gl->gl_state), | |
1722 | gl->gl_name.ln_type, | |
1723 | (unsigned long long)gl->gl_name.ln_number, | |
1724 | gflags2str(gflags_buf, &gl->gl_flags), | |
1725 | state2str(gl->gl_target), | |
1726 | state2str(gl->gl_demote_state), dtime, | |
1727 | atomic_read(&gl->gl_lvb_count), | |
1728 | atomic_read(&gl->gl_ail_count), | |
1729 | atomic_read(&gl->gl_ref)); | |
b3b94faa | 1730 | |
b3b94faa | 1731 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { |
6802e340 | 1732 | error = dump_holder(seq, gh); |
b3b94faa DT |
1733 | if (error) |
1734 | goto out; | |
1735 | } | |
6802e340 SW |
1736 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
1737 | error = glops->go_dump(seq, gl); | |
a91ea69f | 1738 | out: |
b3b94faa DT |
1739 | return error; |
1740 | } | |
1741 | ||
6802e340 SW |
1742 | static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
1743 | { | |
1744 | int ret; | |
1745 | spin_lock(&gl->gl_spin); | |
1746 | ret = __dump_glock(seq, gl); | |
1747 | spin_unlock(&gl->gl_spin); | |
1748 | return ret; | |
1749 | } | |
1750 | ||
b3b94faa DT |
1751 | /** |
1752 | * gfs2_dump_lockstate - print out the current lockstate | |
1753 | * @sdp: the filesystem | |
1754 | * @ub: the buffer to copy the information into | |
1755 | * | |
1756 | * If @ub is NULL, dump the lockstate to the console. | |
1757 | * | |
1758 | */ | |
1759 | ||
08bc2dbc | 1760 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
b3b94faa | 1761 | { |
b3b94faa | 1762 | struct gfs2_glock *gl; |
b6397893 | 1763 | struct hlist_node *h; |
b3b94faa DT |
1764 | unsigned int x; |
1765 | int error = 0; | |
1766 | ||
1767 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
b3b94faa | 1768 | |
087efdd3 | 1769 | read_lock(gl_lock_addr(x)); |
b3b94faa | 1770 | |
b6397893 | 1771 | hlist_for_each_entry(gl, h, &gl_hash_table[x].hb_list, gl_list) { |
85d1da67 SW |
1772 | if (gl->gl_sbd != sdp) |
1773 | continue; | |
b3b94faa | 1774 | |
7c52b166 | 1775 | error = dump_glock(NULL, gl); |
b3b94faa DT |
1776 | if (error) |
1777 | break; | |
1778 | } | |
1779 | ||
087efdd3 | 1780 | read_unlock(gl_lock_addr(x)); |
b3b94faa DT |
1781 | |
1782 | if (error) | |
1783 | break; | |
1784 | } | |
1785 | ||
1786 | ||
1787 | return error; | |
1788 | } | |
1789 | ||
8fbbfd21 | 1790 | |
85d1da67 SW |
1791 | int __init gfs2_glock_init(void) |
1792 | { | |
1793 | unsigned i; | |
1794 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
b6397893 | 1795 | INIT_HLIST_HEAD(&gl_hash_table[i].hb_list); |
85d1da67 | 1796 | } |
087efdd3 SW |
1797 | #ifdef GL_HASH_LOCK_SZ |
1798 | for(i = 0; i < GL_HASH_LOCK_SZ; i++) { | |
1799 | rwlock_init(&gl_hash_locks[i]); | |
1800 | } | |
1801 | #endif | |
8fbbfd21 | 1802 | |
c4f68a13 | 1803 | glock_workqueue = create_workqueue("glock_workqueue"); |
97cc1025 | 1804 | if (IS_ERR(glock_workqueue)) |
c4f68a13 | 1805 | return PTR_ERR(glock_workqueue); |
97cc1025 SW |
1806 | |
1807 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1808 | |
85d1da67 SW |
1809 | return 0; |
1810 | } | |
1811 | ||
8fbbfd21 SW |
1812 | void gfs2_glock_exit(void) |
1813 | { | |
97cc1025 | 1814 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1815 | destroy_workqueue(glock_workqueue); |
8fbbfd21 SW |
1816 | } |
1817 | ||
6802e340 | 1818 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1819 | { |
7b08fc62 SW |
1820 | struct gfs2_glock *gl; |
1821 | ||
a947e033 | 1822 | restart: |
7a0079d9 | 1823 | read_lock(gl_lock_addr(gi->hash)); |
7b08fc62 SW |
1824 | gl = gi->gl; |
1825 | if (gl) { | |
a947e033 AD |
1826 | gi->gl = hlist_entry(gl->gl_list.next, |
1827 | struct gfs2_glock, gl_list); | |
c1e817d0 SW |
1828 | } else { |
1829 | gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first, | |
1830 | struct gfs2_glock, gl_list); | |
7c52b166 | 1831 | } |
c1e817d0 SW |
1832 | if (gi->gl) |
1833 | gfs2_glock_hold(gi->gl); | |
7a0079d9 | 1834 | read_unlock(gl_lock_addr(gi->hash)); |
7b08fc62 SW |
1835 | if (gl) |
1836 | gfs2_glock_put(gl); | |
6802e340 | 1837 | while (gi->gl == NULL) { |
c1e817d0 | 1838 | gi->hash++; |
7b08fc62 SW |
1839 | if (gi->hash >= GFS2_GL_HASH_SIZE) |
1840 | return 1; | |
1841 | read_lock(gl_lock_addr(gi->hash)); | |
1842 | gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first, | |
1843 | struct gfs2_glock, gl_list); | |
1844 | if (gi->gl) | |
1845 | gfs2_glock_hold(gi->gl); | |
1846 | read_unlock(gl_lock_addr(gi->hash)); | |
1847 | } | |
a947e033 AD |
1848 | |
1849 | if (gi->sdp != gi->gl->gl_sbd) | |
1850 | goto restart; | |
1851 | ||
7c52b166 RP |
1852 | return 0; |
1853 | } | |
1854 | ||
6802e340 | 1855 | static void gfs2_glock_iter_free(struct gfs2_glock_iter *gi) |
7c52b166 | 1856 | { |
7b08fc62 SW |
1857 | if (gi->gl) |
1858 | gfs2_glock_put(gi->gl); | |
a947e033 | 1859 | gi->gl = NULL; |
7c52b166 RP |
1860 | } |
1861 | ||
6802e340 | 1862 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1863 | { |
6802e340 | 1864 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1865 | loff_t n = *pos; |
1866 | ||
6802e340 | 1867 | gi->hash = 0; |
7c52b166 | 1868 | |
6802e340 | 1869 | do { |
7c52b166 RP |
1870 | if (gfs2_glock_iter_next(gi)) { |
1871 | gfs2_glock_iter_free(gi); | |
1872 | return NULL; | |
1873 | } | |
6802e340 | 1874 | } while (n--); |
7c52b166 | 1875 | |
6802e340 | 1876 | return gi->gl; |
7c52b166 RP |
1877 | } |
1878 | ||
6802e340 | 1879 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1880 | loff_t *pos) |
1881 | { | |
6802e340 | 1882 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1883 | |
1884 | (*pos)++; | |
1885 | ||
1886 | if (gfs2_glock_iter_next(gi)) { | |
1887 | gfs2_glock_iter_free(gi); | |
1888 | return NULL; | |
1889 | } | |
1890 | ||
6802e340 | 1891 | return gi->gl; |
7c52b166 RP |
1892 | } |
1893 | ||
6802e340 | 1894 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1895 | { |
6802e340 SW |
1896 | struct gfs2_glock_iter *gi = seq->private; |
1897 | gfs2_glock_iter_free(gi); | |
7c52b166 RP |
1898 | } |
1899 | ||
6802e340 | 1900 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1901 | { |
6802e340 | 1902 | return dump_glock(seq, iter_ptr); |
7c52b166 RP |
1903 | } |
1904 | ||
4ef29002 | 1905 | static const struct seq_operations gfs2_glock_seq_ops = { |
7c52b166 RP |
1906 | .start = gfs2_glock_seq_start, |
1907 | .next = gfs2_glock_seq_next, | |
1908 | .stop = gfs2_glock_seq_stop, | |
1909 | .show = gfs2_glock_seq_show, | |
1910 | }; | |
1911 | ||
1912 | static int gfs2_debugfs_open(struct inode *inode, struct file *file) | |
1913 | { | |
6802e340 SW |
1914 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
1915 | sizeof(struct gfs2_glock_iter)); | |
1916 | if (ret == 0) { | |
1917 | struct seq_file *seq = file->private_data; | |
1918 | struct gfs2_glock_iter *gi = seq->private; | |
1919 | gi->sdp = inode->i_private; | |
1920 | } | |
1921 | return ret; | |
7c52b166 RP |
1922 | } |
1923 | ||
1924 | static const struct file_operations gfs2_debug_fops = { | |
1925 | .owner = THIS_MODULE, | |
1926 | .open = gfs2_debugfs_open, | |
1927 | .read = seq_read, | |
1928 | .llseek = seq_lseek, | |
6802e340 | 1929 | .release = seq_release_private, |
7c52b166 RP |
1930 | }; |
1931 | ||
1932 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
1933 | { | |
5f882096 RP |
1934 | sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root); |
1935 | if (!sdp->debugfs_dir) | |
1936 | return -ENOMEM; | |
1937 | sdp->debugfs_dentry_glocks = debugfs_create_file("glocks", | |
1938 | S_IFREG | S_IRUGO, | |
1939 | sdp->debugfs_dir, sdp, | |
1940 | &gfs2_debug_fops); | |
1941 | if (!sdp->debugfs_dentry_glocks) | |
7c52b166 RP |
1942 | return -ENOMEM; |
1943 | ||
1944 | return 0; | |
1945 | } | |
1946 | ||
1947 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) | |
1948 | { | |
5f882096 RP |
1949 | if (sdp && sdp->debugfs_dir) { |
1950 | if (sdp->debugfs_dentry_glocks) { | |
1951 | debugfs_remove(sdp->debugfs_dentry_glocks); | |
1952 | sdp->debugfs_dentry_glocks = NULL; | |
1953 | } | |
1954 | debugfs_remove(sdp->debugfs_dir); | |
1955 | sdp->debugfs_dir = NULL; | |
1956 | } | |
7c52b166 RP |
1957 | } |
1958 | ||
1959 | int gfs2_register_debugfs(void) | |
1960 | { | |
1961 | gfs2_root = debugfs_create_dir("gfs2", NULL); | |
1962 | return gfs2_root ? 0 : -ENOMEM; | |
1963 | } | |
1964 | ||
1965 | void gfs2_unregister_debugfs(void) | |
1966 | { | |
1967 | debugfs_remove(gfs2_root); | |
5f882096 | 1968 | gfs2_root = NULL; |
7c52b166 | 1969 | } |