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 | ||
d77d1b58 JP |
10 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
11 | ||
b3b94faa DT |
12 | #include <linux/sched.h> |
13 | #include <linux/slab.h> | |
14 | #include <linux/spinlock.h> | |
b3b94faa DT |
15 | #include <linux/buffer_head.h> |
16 | #include <linux/delay.h> | |
17 | #include <linux/sort.h> | |
18 | #include <linux/jhash.h> | |
d0dc80db | 19 | #include <linux/kallsyms.h> |
5c676f6d | 20 | #include <linux/gfs2_ondisk.h> |
24264434 | 21 | #include <linux/list.h> |
fee852e3 | 22 | #include <linux/wait.h> |
95d97b7d | 23 | #include <linux/module.h> |
b3b94faa | 24 | #include <asm/uaccess.h> |
7c52b166 RP |
25 | #include <linux/seq_file.h> |
26 | #include <linux/debugfs.h> | |
8fbbfd21 SW |
27 | #include <linux/kthread.h> |
28 | #include <linux/freezer.h> | |
c4f68a13 BM |
29 | #include <linux/workqueue.h> |
30 | #include <linux/jiffies.h> | |
bc015cb8 SW |
31 | #include <linux/rcupdate.h> |
32 | #include <linux/rculist_bl.h> | |
33 | #include <linux/bit_spinlock.h> | |
a245769f | 34 | #include <linux/percpu.h> |
4506a519 | 35 | #include <linux/list_sort.h> |
e66cf161 | 36 | #include <linux/lockref.h> |
b3b94faa DT |
37 | |
38 | #include "gfs2.h" | |
5c676f6d | 39 | #include "incore.h" |
b3b94faa DT |
40 | #include "glock.h" |
41 | #include "glops.h" | |
42 | #include "inode.h" | |
b3b94faa DT |
43 | #include "lops.h" |
44 | #include "meta_io.h" | |
45 | #include "quota.h" | |
46 | #include "super.h" | |
5c676f6d | 47 | #include "util.h" |
813e0c46 | 48 | #include "bmap.h" |
63997775 SW |
49 | #define CREATE_TRACE_POINTS |
50 | #include "trace_gfs2.h" | |
b3b94faa | 51 | |
6802e340 | 52 | struct gfs2_glock_iter { |
ba1ddcb6 SW |
53 | int hash; /* hash bucket index */ |
54 | unsigned nhash; /* Index within current bucket */ | |
55 | struct gfs2_sbd *sdp; /* incore superblock */ | |
56 | struct gfs2_glock *gl; /* current glock struct */ | |
57 | loff_t last_pos; /* last position */ | |
7c52b166 RP |
58 | }; |
59 | ||
b3b94faa DT |
60 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
61 | ||
6802e340 | 62 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target); |
c4f68a13 | 63 | |
7c52b166 | 64 | static struct dentry *gfs2_root; |
c4f68a13 | 65 | static struct workqueue_struct *glock_workqueue; |
b94a170e | 66 | struct workqueue_struct *gfs2_delete_workqueue; |
97cc1025 SW |
67 | static LIST_HEAD(lru_list); |
68 | static atomic_t lru_count = ATOMIC_INIT(0); | |
eb8374e7 | 69 | static DEFINE_SPINLOCK(lru_lock); |
08bc2dbc | 70 | |
b6397893 | 71 | #define GFS2_GL_HASH_SHIFT 15 |
087efdd3 SW |
72 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
73 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) | |
74 | ||
bc015cb8 | 75 | static struct hlist_bl_head gl_hash_table[GFS2_GL_HASH_SIZE]; |
04b933f2 | 76 | static struct dentry *gfs2_root; |
087efdd3 | 77 | |
b3b94faa DT |
78 | /** |
79 | * gl_hash() - Turn glock number into hash bucket number | |
80 | * @lock: The glock number | |
81 | * | |
82 | * Returns: The number of the corresponding hash bucket | |
83 | */ | |
84 | ||
b8547856 SW |
85 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
86 | const struct lm_lockname *name) | |
b3b94faa DT |
87 | { |
88 | unsigned int h; | |
89 | ||
cd915493 | 90 | h = jhash(&name->ln_number, sizeof(u64), 0); |
b3b94faa | 91 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
b8547856 | 92 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
b3b94faa DT |
93 | h &= GFS2_GL_HASH_MASK; |
94 | ||
95 | return h; | |
96 | } | |
97 | ||
bc015cb8 SW |
98 | static inline void spin_lock_bucket(unsigned int hash) |
99 | { | |
1879fd6a | 100 | hlist_bl_lock(&gl_hash_table[hash]); |
bc015cb8 | 101 | } |
b3b94faa | 102 | |
bc015cb8 SW |
103 | static inline void spin_unlock_bucket(unsigned int hash) |
104 | { | |
1879fd6a | 105 | hlist_bl_unlock(&gl_hash_table[hash]); |
bc015cb8 | 106 | } |
b3b94faa | 107 | |
fc0e38da | 108 | static void gfs2_glock_dealloc(struct rcu_head *rcu) |
b3b94faa | 109 | { |
bc015cb8 | 110 | struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu); |
b3b94faa | 111 | |
dba2d70c | 112 | if (gl->gl_ops->go_flags & GLOF_ASPACE) { |
bc015cb8 | 113 | kmem_cache_free(gfs2_glock_aspace_cachep, gl); |
dba2d70c | 114 | } else { |
4e2f8849 | 115 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 116 | kmem_cache_free(gfs2_glock_cachep, gl); |
dba2d70c | 117 | } |
fc0e38da SW |
118 | } |
119 | ||
120 | void gfs2_glock_free(struct gfs2_glock *gl) | |
b3b94faa DT |
121 | { |
122 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
b3b94faa | 123 | |
fc0e38da | 124 | call_rcu(&gl->gl_rcu, gfs2_glock_dealloc); |
bc015cb8 SW |
125 | if (atomic_dec_and_test(&sdp->sd_glock_disposal)) |
126 | wake_up(&sdp->sd_glock_wait); | |
b3b94faa DT |
127 | } |
128 | ||
129 | /** | |
130 | * gfs2_glock_hold() - increment reference count on glock | |
131 | * @gl: The glock to hold | |
132 | * | |
133 | */ | |
134 | ||
e66cf161 | 135 | static void gfs2_glock_hold(struct gfs2_glock *gl) |
b3b94faa | 136 | { |
e66cf161 SW |
137 | GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); |
138 | lockref_get(&gl->gl_lockref); | |
b3b94faa DT |
139 | } |
140 | ||
8ff22a6f BM |
141 | /** |
142 | * demote_ok - Check to see if it's ok to unlock a glock | |
143 | * @gl: the glock | |
144 | * | |
145 | * Returns: 1 if it's ok | |
146 | */ | |
147 | ||
148 | static int demote_ok(const struct gfs2_glock *gl) | |
149 | { | |
150 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
151 | ||
152 | if (gl->gl_state == LM_ST_UNLOCKED) | |
153 | return 0; | |
f42ab085 | 154 | if (!list_empty(&gl->gl_holders)) |
8ff22a6f BM |
155 | return 0; |
156 | if (glops->go_demote_ok) | |
157 | return glops->go_demote_ok(gl); | |
158 | return 1; | |
159 | } | |
160 | ||
bc015cb8 | 161 | |
29687a2a SW |
162 | void gfs2_glock_add_to_lru(struct gfs2_glock *gl) |
163 | { | |
164 | spin_lock(&lru_lock); | |
165 | ||
166 | if (!list_empty(&gl->gl_lru)) | |
167 | list_del_init(&gl->gl_lru); | |
168 | else | |
169 | atomic_inc(&lru_count); | |
170 | ||
171 | list_add_tail(&gl->gl_lru, &lru_list); | |
627c10b7 | 172 | set_bit(GLF_LRU, &gl->gl_flags); |
29687a2a SW |
173 | spin_unlock(&lru_lock); |
174 | } | |
175 | ||
4043b886 | 176 | static void __gfs2_glock_remove_from_lru(struct gfs2_glock *gl) |
f42ab085 | 177 | { |
f42ab085 SW |
178 | if (!list_empty(&gl->gl_lru)) { |
179 | list_del_init(&gl->gl_lru); | |
180 | atomic_dec(&lru_count); | |
181 | clear_bit(GLF_LRU, &gl->gl_flags); | |
182 | } | |
4043b886 SW |
183 | } |
184 | ||
185 | static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl) | |
186 | { | |
187 | spin_lock(&lru_lock); | |
188 | __gfs2_glock_remove_from_lru(gl); | |
f42ab085 SW |
189 | spin_unlock(&lru_lock); |
190 | } | |
191 | ||
b3b94faa DT |
192 | /** |
193 | * gfs2_glock_put() - Decrement reference count on glock | |
194 | * @gl: The glock to put | |
195 | * | |
196 | */ | |
197 | ||
bc015cb8 | 198 | void gfs2_glock_put(struct gfs2_glock *gl) |
b3b94faa | 199 | { |
bc015cb8 SW |
200 | struct gfs2_sbd *sdp = gl->gl_sbd; |
201 | struct address_space *mapping = gfs2_glock2aspace(gl); | |
b3b94faa | 202 | |
e66cf161 SW |
203 | if (lockref_put_or_lock(&gl->gl_lockref)) |
204 | return; | |
205 | ||
206 | lockref_mark_dead(&gl->gl_lockref); | |
207 | ||
208 | spin_lock(&lru_lock); | |
209 | __gfs2_glock_remove_from_lru(gl); | |
210 | spin_unlock(&lru_lock); | |
211 | spin_unlock(&gl->gl_lockref.lock); | |
212 | spin_lock_bucket(gl->gl_hash); | |
213 | hlist_bl_del_rcu(&gl->gl_list); | |
214 | spin_unlock_bucket(gl->gl_hash); | |
215 | GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); | |
216 | GLOCK_BUG_ON(gl, mapping && mapping->nrpages); | |
217 | trace_gfs2_glock_put(gl); | |
218 | sdp->sd_lockstruct.ls_ops->lm_put_lock(gl); | |
b3b94faa DT |
219 | } |
220 | ||
b3b94faa DT |
221 | /** |
222 | * search_bucket() - Find struct gfs2_glock by lock number | |
223 | * @bucket: the bucket to search | |
224 | * @name: The lock name | |
225 | * | |
226 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
227 | */ | |
228 | ||
37b2fa6a | 229 | static struct gfs2_glock *search_bucket(unsigned int hash, |
899be4d3 | 230 | const struct gfs2_sbd *sdp, |
d6a53727 | 231 | const struct lm_lockname *name) |
b3b94faa DT |
232 | { |
233 | struct gfs2_glock *gl; | |
bc015cb8 | 234 | struct hlist_bl_node *h; |
b3b94faa | 235 | |
bc015cb8 | 236 | hlist_bl_for_each_entry_rcu(gl, h, &gl_hash_table[hash], gl_list) { |
b3b94faa DT |
237 | if (!lm_name_equal(&gl->gl_name, name)) |
238 | continue; | |
899be4d3 SW |
239 | if (gl->gl_sbd != sdp) |
240 | continue; | |
e66cf161 | 241 | if (lockref_get_not_dead(&gl->gl_lockref)) |
bc015cb8 | 242 | return gl; |
b3b94faa DT |
243 | } |
244 | ||
245 | return NULL; | |
246 | } | |
247 | ||
6802e340 SW |
248 | /** |
249 | * may_grant - check if its ok to grant a new lock | |
250 | * @gl: The glock | |
251 | * @gh: The lock request which we wish to grant | |
252 | * | |
253 | * Returns: true if its ok to grant the lock | |
254 | */ | |
255 | ||
256 | static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) | |
257 | { | |
258 | const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list); | |
259 | if ((gh->gh_state == LM_ST_EXCLUSIVE || | |
260 | gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head) | |
261 | return 0; | |
262 | if (gl->gl_state == gh->gh_state) | |
263 | return 1; | |
264 | if (gh->gh_flags & GL_EXACT) | |
265 | return 0; | |
209806ab SW |
266 | if (gl->gl_state == LM_ST_EXCLUSIVE) { |
267 | if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) | |
268 | return 1; | |
269 | if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) | |
270 | return 1; | |
271 | } | |
6802e340 SW |
272 | if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
273 | return 1; | |
274 | return 0; | |
275 | } | |
276 | ||
277 | static void gfs2_holder_wake(struct gfs2_holder *gh) | |
278 | { | |
279 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
280 | smp_mb__after_clear_bit(); | |
281 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); | |
282 | } | |
283 | ||
d5341a92 SW |
284 | /** |
285 | * do_error - Something unexpected has happened during a lock request | |
286 | * | |
287 | */ | |
288 | ||
289 | static inline void do_error(struct gfs2_glock *gl, const int ret) | |
290 | { | |
291 | struct gfs2_holder *gh, *tmp; | |
292 | ||
293 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
294 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
295 | continue; | |
296 | if (ret & LM_OUT_ERROR) | |
297 | gh->gh_error = -EIO; | |
298 | else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) | |
299 | gh->gh_error = GLR_TRYFAILED; | |
300 | else | |
301 | continue; | |
302 | list_del_init(&gh->gh_list); | |
303 | trace_gfs2_glock_queue(gh, 0); | |
304 | gfs2_holder_wake(gh); | |
305 | } | |
306 | } | |
307 | ||
6802e340 SW |
308 | /** |
309 | * do_promote - promote as many requests as possible on the current queue | |
310 | * @gl: The glock | |
311 | * | |
813e0c46 SW |
312 | * Returns: 1 if there is a blocked holder at the head of the list, or 2 |
313 | * if a type specific operation is underway. | |
6802e340 SW |
314 | */ |
315 | ||
316 | static int do_promote(struct gfs2_glock *gl) | |
55ba474d HH |
317 | __releases(&gl->gl_spin) |
318 | __acquires(&gl->gl_spin) | |
6802e340 SW |
319 | { |
320 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
321 | struct gfs2_holder *gh, *tmp; | |
322 | int ret; | |
323 | ||
324 | restart: | |
325 | list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { | |
326 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
327 | continue; | |
328 | if (may_grant(gl, gh)) { | |
329 | if (gh->gh_list.prev == &gl->gl_holders && | |
330 | glops->go_lock) { | |
331 | spin_unlock(&gl->gl_spin); | |
332 | /* FIXME: eliminate this eventually */ | |
333 | ret = glops->go_lock(gh); | |
334 | spin_lock(&gl->gl_spin); | |
335 | if (ret) { | |
813e0c46 SW |
336 | if (ret == 1) |
337 | return 2; | |
6802e340 SW |
338 | gh->gh_error = ret; |
339 | list_del_init(&gh->gh_list); | |
63997775 | 340 | trace_gfs2_glock_queue(gh, 0); |
6802e340 SW |
341 | gfs2_holder_wake(gh); |
342 | goto restart; | |
343 | } | |
344 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 345 | trace_gfs2_promote(gh, 1); |
6802e340 SW |
346 | gfs2_holder_wake(gh); |
347 | goto restart; | |
348 | } | |
349 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
63997775 | 350 | trace_gfs2_promote(gh, 0); |
6802e340 SW |
351 | gfs2_holder_wake(gh); |
352 | continue; | |
353 | } | |
354 | if (gh->gh_list.prev == &gl->gl_holders) | |
355 | return 1; | |
d5341a92 | 356 | do_error(gl, 0); |
6802e340 SW |
357 | break; |
358 | } | |
359 | return 0; | |
360 | } | |
361 | ||
6802e340 SW |
362 | /** |
363 | * find_first_waiter - find the first gh that's waiting for the glock | |
364 | * @gl: the glock | |
365 | */ | |
366 | ||
367 | static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) | |
368 | { | |
369 | struct gfs2_holder *gh; | |
370 | ||
371 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
372 | if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
373 | return gh; | |
374 | } | |
375 | return NULL; | |
376 | } | |
377 | ||
378 | /** | |
379 | * state_change - record that the glock is now in a different state | |
380 | * @gl: the glock | |
381 | * @new_state the new state | |
382 | * | |
383 | */ | |
384 | ||
385 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
386 | { | |
387 | int held1, held2; | |
388 | ||
389 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
390 | held2 = (new_state != LM_ST_UNLOCKED); | |
391 | ||
392 | if (held1 != held2) { | |
e66cf161 | 393 | GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); |
6802e340 | 394 | if (held2) |
e66cf161 | 395 | gl->gl_lockref.count++; |
6802e340 | 396 | else |
e66cf161 | 397 | gl->gl_lockref.count--; |
6802e340 | 398 | } |
7b5e3d5f SW |
399 | if (held1 && held2 && list_empty(&gl->gl_holders)) |
400 | clear_bit(GLF_QUEUED, &gl->gl_flags); | |
6802e340 | 401 | |
7cf8dcd3 BP |
402 | if (new_state != gl->gl_target) |
403 | /* shorten our minimum hold time */ | |
404 | gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR, | |
405 | GL_GLOCK_MIN_HOLD); | |
6802e340 SW |
406 | gl->gl_state = new_state; |
407 | gl->gl_tchange = jiffies; | |
408 | } | |
409 | ||
410 | static void gfs2_demote_wake(struct gfs2_glock *gl) | |
411 | { | |
412 | gl->gl_demote_state = LM_ST_EXCLUSIVE; | |
413 | clear_bit(GLF_DEMOTE, &gl->gl_flags); | |
414 | smp_mb__after_clear_bit(); | |
415 | wake_up_bit(&gl->gl_flags, GLF_DEMOTE); | |
416 | } | |
417 | ||
418 | /** | |
419 | * finish_xmote - The DLM has replied to one of our lock requests | |
420 | * @gl: The glock | |
421 | * @ret: The status from the DLM | |
422 | * | |
423 | */ | |
424 | ||
425 | static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) | |
426 | { | |
427 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
428 | struct gfs2_holder *gh; | |
429 | unsigned state = ret & LM_OUT_ST_MASK; | |
813e0c46 | 430 | int rv; |
6802e340 SW |
431 | |
432 | spin_lock(&gl->gl_spin); | |
63997775 | 433 | trace_gfs2_glock_state_change(gl, state); |
6802e340 SW |
434 | state_change(gl, state); |
435 | gh = find_first_waiter(gl); | |
436 | ||
437 | /* Demote to UN request arrived during demote to SH or DF */ | |
438 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && | |
439 | state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) | |
440 | gl->gl_target = LM_ST_UNLOCKED; | |
441 | ||
442 | /* Check for state != intended state */ | |
443 | if (unlikely(state != gl->gl_target)) { | |
444 | if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) { | |
445 | /* move to back of queue and try next entry */ | |
446 | if (ret & LM_OUT_CANCELED) { | |
447 | if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0) | |
448 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
449 | gh = find_first_waiter(gl); | |
450 | gl->gl_target = gh->gh_state; | |
451 | goto retry; | |
452 | } | |
453 | /* Some error or failed "try lock" - report it */ | |
454 | if ((ret & LM_OUT_ERROR) || | |
455 | (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
456 | gl->gl_target = gl->gl_state; | |
457 | do_error(gl, ret); | |
458 | goto out; | |
459 | } | |
460 | } | |
461 | switch(state) { | |
462 | /* Unlocked due to conversion deadlock, try again */ | |
463 | case LM_ST_UNLOCKED: | |
464 | retry: | |
465 | do_xmote(gl, gh, gl->gl_target); | |
466 | break; | |
467 | /* Conversion fails, unlock and try again */ | |
468 | case LM_ST_SHARED: | |
469 | case LM_ST_DEFERRED: | |
470 | do_xmote(gl, gh, LM_ST_UNLOCKED); | |
471 | break; | |
472 | default: /* Everything else */ | |
d77d1b58 | 473 | pr_err("wanted %u got %u\n", gl->gl_target, state); |
6802e340 SW |
474 | GLOCK_BUG_ON(gl, 1); |
475 | } | |
476 | spin_unlock(&gl->gl_spin); | |
6802e340 SW |
477 | return; |
478 | } | |
479 | ||
480 | /* Fast path - we got what we asked for */ | |
481 | if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) | |
482 | gfs2_demote_wake(gl); | |
483 | if (state != LM_ST_UNLOCKED) { | |
484 | if (glops->go_xmote_bh) { | |
6802e340 SW |
485 | spin_unlock(&gl->gl_spin); |
486 | rv = glops->go_xmote_bh(gl, gh); | |
6802e340 SW |
487 | spin_lock(&gl->gl_spin); |
488 | if (rv) { | |
489 | do_error(gl, rv); | |
490 | goto out; | |
491 | } | |
492 | } | |
813e0c46 SW |
493 | rv = do_promote(gl); |
494 | if (rv == 2) | |
495 | goto out_locked; | |
6802e340 SW |
496 | } |
497 | out: | |
498 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
813e0c46 | 499 | out_locked: |
6802e340 | 500 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
501 | } |
502 | ||
6802e340 SW |
503 | /** |
504 | * do_xmote - Calls the DLM to change the state of a lock | |
505 | * @gl: The lock state | |
506 | * @gh: The holder (only for promotes) | |
507 | * @target: The target lock state | |
508 | * | |
509 | */ | |
510 | ||
511 | static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) | |
55ba474d HH |
512 | __releases(&gl->gl_spin) |
513 | __acquires(&gl->gl_spin) | |
6802e340 SW |
514 | { |
515 | const struct gfs2_glock_operations *glops = gl->gl_ops; | |
516 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
517 | unsigned int lck_flags = gh ? gh->gh_flags : 0; | |
518 | int ret; | |
519 | ||
520 | lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | | |
521 | LM_FLAG_PRIORITY); | |
921169ca SW |
522 | GLOCK_BUG_ON(gl, gl->gl_state == target); |
523 | GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target); | |
6802e340 SW |
524 | if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) && |
525 | glops->go_inval) { | |
526 | set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
527 | do_error(gl, 0); /* Fail queued try locks */ | |
528 | } | |
47a25380 | 529 | gl->gl_req = target; |
a245769f SW |
530 | set_bit(GLF_BLOCKING, &gl->gl_flags); |
531 | if ((gl->gl_req == LM_ST_UNLOCKED) || | |
532 | (gl->gl_state == LM_ST_EXCLUSIVE) || | |
533 | (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB))) | |
534 | clear_bit(GLF_BLOCKING, &gl->gl_flags); | |
6802e340 | 535 | spin_unlock(&gl->gl_spin); |
06dfc306 BP |
536 | if (glops->go_sync) |
537 | glops->go_sync(gl); | |
6802e340 SW |
538 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
539 | glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA); | |
540 | clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags); | |
541 | ||
542 | gfs2_glock_hold(gl); | |
921169ca SW |
543 | if (sdp->sd_lockstruct.ls_ops->lm_lock) { |
544 | /* lock_dlm */ | |
545 | ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags); | |
dba2d70c | 546 | if (ret) { |
d77d1b58 | 547 | pr_err("lm_lock ret %d\n", ret); |
dba2d70c DT |
548 | GLOCK_BUG_ON(gl, 1); |
549 | } | |
921169ca SW |
550 | } else { /* lock_nolock */ |
551 | finish_xmote(gl, target); | |
6802e340 SW |
552 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
553 | gfs2_glock_put(gl); | |
6802e340 | 554 | } |
921169ca | 555 | |
6802e340 SW |
556 | spin_lock(&gl->gl_spin); |
557 | } | |
558 | ||
559 | /** | |
560 | * find_first_holder - find the first "holder" gh | |
561 | * @gl: the glock | |
562 | */ | |
563 | ||
564 | static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) | |
565 | { | |
566 | struct gfs2_holder *gh; | |
567 | ||
568 | if (!list_empty(&gl->gl_holders)) { | |
569 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
570 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
571 | return gh; | |
572 | } | |
573 | return NULL; | |
574 | } | |
575 | ||
576 | /** | |
577 | * run_queue - do all outstanding tasks related to a glock | |
578 | * @gl: The glock in question | |
579 | * @nonblock: True if we must not block in run_queue | |
580 | * | |
581 | */ | |
582 | ||
583 | static void run_queue(struct gfs2_glock *gl, const int nonblock) | |
55ba474d HH |
584 | __releases(&gl->gl_spin) |
585 | __acquires(&gl->gl_spin) | |
6802e340 SW |
586 | { |
587 | struct gfs2_holder *gh = NULL; | |
813e0c46 | 588 | int ret; |
6802e340 SW |
589 | |
590 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) | |
591 | return; | |
592 | ||
593 | GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)); | |
594 | ||
595 | if (test_bit(GLF_DEMOTE, &gl->gl_flags) && | |
596 | gl->gl_demote_state != gl->gl_state) { | |
597 | if (find_first_holder(gl)) | |
d8348de0 | 598 | goto out_unlock; |
6802e340 SW |
599 | if (nonblock) |
600 | goto out_sched; | |
601 | set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); | |
265d529c | 602 | GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); |
6802e340 SW |
603 | gl->gl_target = gl->gl_demote_state; |
604 | } else { | |
605 | if (test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
606 | gfs2_demote_wake(gl); | |
813e0c46 SW |
607 | ret = do_promote(gl); |
608 | if (ret == 0) | |
d8348de0 | 609 | goto out_unlock; |
813e0c46 | 610 | if (ret == 2) |
a228df63 | 611 | goto out; |
6802e340 SW |
612 | gh = find_first_waiter(gl); |
613 | gl->gl_target = gh->gh_state; | |
614 | if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) | |
615 | do_error(gl, 0); /* Fail queued try locks */ | |
616 | } | |
617 | do_xmote(gl, gh, gl->gl_target); | |
a228df63 | 618 | out: |
6802e340 SW |
619 | return; |
620 | ||
621 | out_sched: | |
7e71c55e SW |
622 | clear_bit(GLF_LOCK, &gl->gl_flags); |
623 | smp_mb__after_clear_bit(); | |
e66cf161 | 624 | gl->gl_lockref.count++; |
6802e340 | 625 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 626 | gl->gl_lockref.count--; |
7e71c55e SW |
627 | return; |
628 | ||
d8348de0 | 629 | out_unlock: |
6802e340 | 630 | clear_bit(GLF_LOCK, &gl->gl_flags); |
7e71c55e SW |
631 | smp_mb__after_clear_bit(); |
632 | return; | |
6802e340 SW |
633 | } |
634 | ||
b94a170e BM |
635 | static void delete_work_func(struct work_struct *work) |
636 | { | |
637 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete); | |
638 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
044b9414 | 639 | struct gfs2_inode *ip; |
b94a170e | 640 | struct inode *inode; |
044b9414 SW |
641 | u64 no_addr = gl->gl_name.ln_number; |
642 | ||
643 | ip = gl->gl_object; | |
644 | /* Note: Unsafe to dereference ip as we don't hold right refs/locks */ | |
b94a170e | 645 | |
b94a170e | 646 | if (ip) |
4667a0ec | 647 | inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1); |
044b9414 SW |
648 | else |
649 | inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED); | |
650 | if (inode && !IS_ERR(inode)) { | |
651 | d_prune_aliases(inode); | |
652 | iput(inode); | |
b94a170e BM |
653 | } |
654 | gfs2_glock_put(gl); | |
655 | } | |
656 | ||
c4f68a13 BM |
657 | static void glock_work_func(struct work_struct *work) |
658 | { | |
6802e340 | 659 | unsigned long delay = 0; |
c4f68a13 | 660 | struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work); |
26bb7505 | 661 | int drop_ref = 0; |
c4f68a13 | 662 | |
26bb7505 | 663 | if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) { |
6802e340 | 664 | finish_xmote(gl, gl->gl_reply); |
26bb7505 SW |
665 | drop_ref = 1; |
666 | } | |
c4f68a13 | 667 | spin_lock(&gl->gl_spin); |
f90e5b5b | 668 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
265d529c SW |
669 | gl->gl_state != LM_ST_UNLOCKED && |
670 | gl->gl_demote_state != LM_ST_EXCLUSIVE) { | |
6802e340 | 671 | unsigned long holdtime, now = jiffies; |
f90e5b5b | 672 | |
7cf8dcd3 | 673 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
6802e340 SW |
674 | if (time_before(now, holdtime)) |
675 | delay = holdtime - now; | |
f90e5b5b BP |
676 | |
677 | if (!delay) { | |
678 | clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags); | |
679 | set_bit(GLF_DEMOTE, &gl->gl_flags); | |
680 | } | |
6802e340 SW |
681 | } |
682 | run_queue(gl, 0); | |
c4f68a13 | 683 | spin_unlock(&gl->gl_spin); |
7cf8dcd3 | 684 | if (!delay) |
6802e340 | 685 | gfs2_glock_put(gl); |
7cf8dcd3 BP |
686 | else { |
687 | if (gl->gl_name.ln_type != LM_TYPE_INODE) | |
688 | delay = 0; | |
689 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) | |
690 | gfs2_glock_put(gl); | |
691 | } | |
26bb7505 SW |
692 | if (drop_ref) |
693 | gfs2_glock_put(gl); | |
c4f68a13 BM |
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 | { | |
009d8518 | 713 | struct super_block *s = sdp->sd_vfs; |
37b2fa6a | 714 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
b3b94faa | 715 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 716 | unsigned int hash = gl_hash(sdp, &name); |
009d8518 | 717 | struct address_space *mapping; |
bc015cb8 | 718 | struct kmem_cache *cachep; |
b3b94faa | 719 | |
bc015cb8 | 720 | rcu_read_lock(); |
37b2fa6a | 721 | gl = search_bucket(hash, sdp, &name); |
bc015cb8 | 722 | rcu_read_unlock(); |
b3b94faa | 723 | |
64d576ba SW |
724 | *glp = gl; |
725 | if (gl) | |
b3b94faa | 726 | return 0; |
64d576ba SW |
727 | if (!create) |
728 | return -ENOENT; | |
b3b94faa | 729 | |
009d8518 | 730 | if (glops->go_flags & GLOF_ASPACE) |
bc015cb8 | 731 | cachep = gfs2_glock_aspace_cachep; |
009d8518 | 732 | else |
bc015cb8 SW |
733 | cachep = gfs2_glock_cachep; |
734 | gl = kmem_cache_alloc(cachep, GFP_KERNEL); | |
b3b94faa DT |
735 | if (!gl) |
736 | return -ENOMEM; | |
737 | ||
dba2d70c | 738 | memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); |
dba2d70c DT |
739 | |
740 | if (glops->go_flags & GLOF_LVB) { | |
4e2f8849 DT |
741 | gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_KERNEL); |
742 | if (!gl->gl_lksb.sb_lvbptr) { | |
dba2d70c DT |
743 | kmem_cache_free(cachep, gl); |
744 | return -ENOMEM; | |
745 | } | |
dba2d70c DT |
746 | } |
747 | ||
8f05228e | 748 | atomic_inc(&sdp->sd_glock_disposal); |
a245769f | 749 | gl->gl_sbd = sdp; |
ec45d9f5 | 750 | gl->gl_flags = 0; |
b3b94faa | 751 | gl->gl_name = name; |
e66cf161 | 752 | gl->gl_lockref.count = 1; |
b3b94faa | 753 | gl->gl_state = LM_ST_UNLOCKED; |
6802e340 | 754 | gl->gl_target = LM_ST_UNLOCKED; |
c4f68a13 | 755 | gl->gl_demote_state = LM_ST_EXCLUSIVE; |
37b2fa6a | 756 | gl->gl_hash = hash; |
b3b94faa | 757 | gl->gl_ops = glops; |
a245769f SW |
758 | gl->gl_dstamp = ktime_set(0, 0); |
759 | preempt_disable(); | |
760 | /* We use the global stats to estimate the initial per-glock stats */ | |
761 | gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type]; | |
762 | preempt_enable(); | |
763 | gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0; | |
764 | gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0; | |
c4f68a13 | 765 | gl->gl_tchange = jiffies; |
ec45d9f5 | 766 | gl->gl_object = NULL; |
7cf8dcd3 | 767 | gl->gl_hold_time = GL_GLOCK_DFT_HOLD; |
c4f68a13 | 768 | INIT_DELAYED_WORK(&gl->gl_work, glock_work_func); |
b94a170e | 769 | INIT_WORK(&gl->gl_delete, delete_work_func); |
b3b94faa | 770 | |
009d8518 SW |
771 | mapping = gfs2_glock2aspace(gl); |
772 | if (mapping) { | |
773 | mapping->a_ops = &gfs2_meta_aops; | |
774 | mapping->host = s->s_bdev->bd_inode; | |
775 | mapping->flags = 0; | |
776 | mapping_set_gfp_mask(mapping, GFP_NOFS); | |
252aa6f5 | 777 | mapping->private_data = NULL; |
009d8518 SW |
778 | mapping->backing_dev_info = s->s_bdi; |
779 | mapping->writeback_index = 0; | |
b3b94faa DT |
780 | } |
781 | ||
bc015cb8 | 782 | spin_lock_bucket(hash); |
37b2fa6a | 783 | tmp = search_bucket(hash, sdp, &name); |
b3b94faa | 784 | if (tmp) { |
bc015cb8 | 785 | spin_unlock_bucket(hash); |
4e2f8849 | 786 | kfree(gl->gl_lksb.sb_lvbptr); |
bc015cb8 | 787 | kmem_cache_free(cachep, gl); |
fc0e38da | 788 | atomic_dec(&sdp->sd_glock_disposal); |
b3b94faa DT |
789 | gl = tmp; |
790 | } else { | |
bc015cb8 SW |
791 | hlist_bl_add_head_rcu(&gl->gl_list, &gl_hash_table[hash]); |
792 | spin_unlock_bucket(hash); | |
b3b94faa DT |
793 | } |
794 | ||
795 | *glp = gl; | |
796 | ||
797 | return 0; | |
b3b94faa DT |
798 | } |
799 | ||
800 | /** | |
801 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
802 | * @gl: the glock | |
803 | * @state: the state we're requesting | |
804 | * @flags: the modifier flags | |
805 | * @gh: the holder structure | |
806 | * | |
807 | */ | |
808 | ||
190562bd | 809 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
810 | struct gfs2_holder *gh) |
811 | { | |
812 | INIT_LIST_HEAD(&gh->gh_list); | |
813 | gh->gh_gl = gl; | |
d0dc80db | 814 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b1e058da | 815 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
816 | gh->gh_state = state; |
817 | gh->gh_flags = flags; | |
818 | gh->gh_error = 0; | |
819 | gh->gh_iflags = 0; | |
b3b94faa DT |
820 | gfs2_glock_hold(gl); |
821 | } | |
822 | ||
823 | /** | |
824 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
825 | * @state: the state we're requesting | |
826 | * @flags: the modifier flags | |
827 | * @gh: the holder structure | |
828 | * | |
829 | * Don't mess with the glock. | |
830 | * | |
831 | */ | |
832 | ||
190562bd | 833 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
834 | { |
835 | gh->gh_state = state; | |
579b78a4 | 836 | gh->gh_flags = flags; |
3b8249f6 | 837 | gh->gh_iflags = 0; |
d0dc80db | 838 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
1a0eae88 BP |
839 | if (gh->gh_owner_pid) |
840 | put_pid(gh->gh_owner_pid); | |
841 | gh->gh_owner_pid = get_pid(task_pid(current)); | |
b3b94faa DT |
842 | } |
843 | ||
844 | /** | |
845 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
846 | * @gh: the holder structure | |
847 | * | |
848 | */ | |
849 | ||
850 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
851 | { | |
b1e058da | 852 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
853 | gfs2_glock_put(gh->gh_gl); |
854 | gh->gh_gl = NULL; | |
d0dc80db | 855 | gh->gh_ip = 0; |
b3b94faa DT |
856 | } |
857 | ||
fe64d517 SW |
858 | /** |
859 | * gfs2_glock_holder_wait | |
860 | * @word: unused | |
861 | * | |
862 | * This function and gfs2_glock_demote_wait both show up in the WCHAN | |
863 | * field. Thus I've separated these otherwise identical functions in | |
864 | * order to be more informative to the user. | |
865 | */ | |
866 | ||
867 | static int gfs2_glock_holder_wait(void *word) | |
fee852e3 SW |
868 | { |
869 | schedule(); | |
870 | return 0; | |
871 | } | |
872 | ||
fe64d517 SW |
873 | static int gfs2_glock_demote_wait(void *word) |
874 | { | |
875 | schedule(); | |
876 | return 0; | |
877 | } | |
878 | ||
07a79049 BP |
879 | /** |
880 | * gfs2_glock_wait - wait on a glock acquisition | |
881 | * @gh: the glock holder | |
882 | * | |
883 | * Returns: 0 on success | |
884 | */ | |
885 | ||
886 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
da755fdb | 887 | { |
7cf8dcd3 BP |
888 | unsigned long time1 = jiffies; |
889 | ||
6802e340 | 890 | might_sleep(); |
fe64d517 | 891 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE); |
7cf8dcd3 BP |
892 | if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */ |
893 | /* Lengthen the minimum hold time. */ | |
894 | gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time + | |
895 | GL_GLOCK_HOLD_INCR, | |
896 | GL_GLOCK_MAX_HOLD); | |
07a79049 | 897 | return gh->gh_error; |
da755fdb SW |
898 | } |
899 | ||
b3b94faa | 900 | /** |
6802e340 SW |
901 | * handle_callback - process a demote request |
902 | * @gl: the glock | |
903 | * @state: the state the caller wants us to change to | |
b3b94faa | 904 | * |
6802e340 SW |
905 | * There are only two requests that we are going to see in actual |
906 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
907 | */ |
908 | ||
6802e340 | 909 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
81ffbf65 | 910 | unsigned long delay, bool remote) |
b3b94faa | 911 | { |
6802e340 | 912 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 913 | |
6802e340 SW |
914 | set_bit(bit, &gl->gl_flags); |
915 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
916 | gl->gl_demote_state = state; | |
917 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
918 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
919 | gl->gl_demote_state != state) { | |
920 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 921 | } |
b94a170e | 922 | if (gl->gl_ops->go_callback) |
81ffbf65 | 923 | gl->gl_ops->go_callback(gl, remote); |
7bd8b2eb | 924 | trace_gfs2_demote_rq(gl, remote); |
b3b94faa DT |
925 | } |
926 | ||
6802e340 | 927 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 | 928 | { |
5e69069c | 929 | struct va_format vaf; |
7c52b166 RP |
930 | va_list args; |
931 | ||
932 | va_start(args, fmt); | |
5e69069c | 933 | |
6802e340 | 934 | if (seq) { |
1bb49303 | 935 | seq_vprintf(seq, fmt, args); |
6802e340 | 936 | } else { |
5e69069c JP |
937 | vaf.fmt = fmt; |
938 | vaf.va = &args; | |
939 | ||
d77d1b58 | 940 | pr_err("%pV", &vaf); |
6802e340 | 941 | } |
5e69069c | 942 | |
7c52b166 RP |
943 | va_end(args); |
944 | } | |
945 | ||
b3b94faa DT |
946 | /** |
947 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
948 | * @gh: the holder structure to add | |
949 | * | |
6802e340 SW |
950 | * Eventually we should move the recursive locking trap to a |
951 | * debugging option or something like that. This is the fast | |
952 | * path and needs to have the minimum number of distractions. | |
953 | * | |
b3b94faa DT |
954 | */ |
955 | ||
6802e340 | 956 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
957 | __releases(&gl->gl_spin) |
958 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
959 | { |
960 | struct gfs2_glock *gl = gh->gh_gl; | |
6802e340 SW |
961 | struct gfs2_sbd *sdp = gl->gl_sbd; |
962 | struct list_head *insert_pt = NULL; | |
963 | struct gfs2_holder *gh2; | |
e5dc76b9 | 964 | int try_futile = 0; |
b3b94faa | 965 | |
b1e058da | 966 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
967 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
968 | BUG(); | |
190562bd | 969 | |
6802e340 SW |
970 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
971 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
e5dc76b9 | 972 | try_futile = !may_grant(gl, gh); |
6802e340 SW |
973 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
974 | goto fail; | |
975 | } | |
976 | ||
977 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
978 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
979 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
980 | goto trap_recursive; | |
e5dc76b9 BP |
981 | if (try_futile && |
982 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
6802e340 SW |
983 | fail: |
984 | gh->gh_error = GLR_TRYFAILED; | |
985 | gfs2_holder_wake(gh); | |
986 | return; | |
b4c20166 | 987 | } |
6802e340 SW |
988 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
989 | continue; | |
990 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
991 | insert_pt = &gh2->gh_list; | |
992 | } | |
7b5e3d5f | 993 | set_bit(GLF_QUEUED, &gl->gl_flags); |
edae38a6 | 994 | trace_gfs2_glock_queue(gh, 1); |
a245769f SW |
995 | gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT); |
996 | gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT); | |
6802e340 SW |
997 | if (likely(insert_pt == NULL)) { |
998 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
999 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
1000 | goto do_cancel; | |
1001 | return; | |
1002 | } | |
1003 | list_add_tail(&gh->gh_list, insert_pt); | |
1004 | do_cancel: | |
1005 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
1006 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
1007 | spin_unlock(&gl->gl_spin); | |
048bca22 | 1008 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
f057f6cd | 1009 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
6802e340 | 1010 | spin_lock(&gl->gl_spin); |
b3b94faa | 1011 | } |
6802e340 | 1012 | return; |
b3b94faa | 1013 | |
6802e340 | 1014 | trap_recursive: |
fc554ed3 FF |
1015 | pr_err("original: %pSR\n", (void *)gh2->gh_ip); |
1016 | pr_err("pid: %d\n", pid_nr(gh2->gh_owner_pid)); | |
1017 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 1018 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); |
fc554ed3 FF |
1019 | pr_err("new: %pSR\n", (void *)gh->gh_ip); |
1020 | pr_err("pid: %d\n", pid_nr(gh->gh_owner_pid)); | |
1021 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 1022 | gh->gh_gl->gl_name.ln_type, gh->gh_state); |
8eae1ca0 | 1023 | gfs2_dump_glock(NULL, gl); |
6802e340 | 1024 | BUG(); |
b3b94faa DT |
1025 | } |
1026 | ||
1027 | /** | |
1028 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1029 | * @gh: the holder structure | |
1030 | * | |
1031 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1032 | * | |
1033 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1034 | */ | |
1035 | ||
1036 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1037 | { | |
1038 | struct gfs2_glock *gl = gh->gh_gl; | |
1039 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1040 | int error = 0; | |
1041 | ||
6802e340 | 1042 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1043 | return -EIO; |
b3b94faa | 1044 | |
f42ab085 SW |
1045 | if (test_bit(GLF_LRU, &gl->gl_flags)) |
1046 | gfs2_glock_remove_from_lru(gl); | |
1047 | ||
b3b94faa DT |
1048 | spin_lock(&gl->gl_spin); |
1049 | add_to_queue(gh); | |
01b172b7 BP |
1050 | if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) && |
1051 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) { | |
0809f6ec | 1052 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
01b172b7 BP |
1053 | gl->gl_lockref.count++; |
1054 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1055 | gl->gl_lockref.count--; | |
1056 | } | |
6802e340 | 1057 | run_queue(gl, 1); |
b3b94faa DT |
1058 | spin_unlock(&gl->gl_spin); |
1059 | ||
6802e340 SW |
1060 | if (!(gh->gh_flags & GL_ASYNC)) |
1061 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1062 | |
b3b94faa DT |
1063 | return error; |
1064 | } | |
1065 | ||
1066 | /** | |
1067 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1068 | * @gh: the holder | |
1069 | * | |
1070 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1071 | */ | |
1072 | ||
1073 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1074 | { | |
6802e340 | 1075 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1076 | } |
1077 | ||
1078 | /** | |
1079 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1080 | * @gh: the glock holder | |
1081 | * | |
1082 | */ | |
1083 | ||
1084 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1085 | { | |
1086 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1087 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1088 | unsigned delay = 0; |
6802e340 | 1089 | int fast_path = 0; |
b3b94faa | 1090 | |
6802e340 | 1091 | spin_lock(&gl->gl_spin); |
b3b94faa | 1092 | if (gh->gh_flags & GL_NOCACHE) |
81ffbf65 | 1093 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
b3b94faa | 1094 | |
b3b94faa | 1095 | list_del_init(&gh->gh_list); |
6802e340 | 1096 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1097 | if (glops->go_unlock) { |
6802e340 | 1098 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1099 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1100 | glops->go_unlock(gh); |
3042a2cc | 1101 | spin_lock(&gl->gl_spin); |
6802e340 | 1102 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1103 | } |
6802e340 SW |
1104 | if (list_empty(&gl->gl_holders) && |
1105 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1106 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1107 | fast_path = 1; | |
b3b94faa | 1108 | } |
4abb6ad9 BP |
1109 | if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl)) |
1110 | gfs2_glock_add_to_lru(gl); | |
1111 | ||
63997775 | 1112 | trace_gfs2_glock_queue(gh, 0); |
b3b94faa | 1113 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1114 | if (likely(fast_path)) |
1115 | return; | |
c4f68a13 BM |
1116 | |
1117 | gfs2_glock_hold(gl); | |
1118 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
7cf8dcd3 BP |
1119 | !test_bit(GLF_DEMOTE, &gl->gl_flags) && |
1120 | gl->gl_name.ln_type == LM_TYPE_INODE) | |
1121 | delay = gl->gl_hold_time; | |
c4f68a13 BM |
1122 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1123 | gfs2_glock_put(gl); | |
b3b94faa DT |
1124 | } |
1125 | ||
d93cfa98 AD |
1126 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1127 | { | |
1128 | struct gfs2_glock *gl = gh->gh_gl; | |
1129 | gfs2_glock_dq(gh); | |
81e1d450 BP |
1130 | might_sleep(); |
1131 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE); | |
d93cfa98 AD |
1132 | } |
1133 | ||
b3b94faa DT |
1134 | /** |
1135 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1136 | * @gh: the holder structure | |
1137 | * | |
1138 | */ | |
1139 | ||
1140 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1141 | { | |
1142 | gfs2_glock_dq(gh); | |
1143 | gfs2_holder_uninit(gh); | |
1144 | } | |
1145 | ||
1146 | /** | |
1147 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1148 | * @sdp: the filesystem | |
1149 | * @number: the lock number | |
1150 | * @glops: the glock operations for the type of glock | |
1151 | * @state: the state to acquire the glock in | |
25985edc | 1152 | * @flags: modifier flags for the acquisition |
b3b94faa DT |
1153 | * @gh: the struct gfs2_holder |
1154 | * | |
1155 | * Returns: errno | |
1156 | */ | |
1157 | ||
cd915493 | 1158 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1159 | const struct gfs2_glock_operations *glops, |
1160 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1161 | { |
1162 | struct gfs2_glock *gl; | |
1163 | int error; | |
1164 | ||
1165 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1166 | if (!error) { | |
1167 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1168 | gfs2_glock_put(gl); | |
1169 | } | |
1170 | ||
1171 | return error; | |
1172 | } | |
1173 | ||
1174 | /** | |
1175 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1176 | * @arg_a: the first structure | |
1177 | * @arg_b: the second structure | |
1178 | * | |
1179 | */ | |
1180 | ||
1181 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1182 | { | |
a5e08a9e SW |
1183 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1184 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1185 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1186 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1187 | |
1188 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1189 | return 1; |
1190 | if (a->ln_number < b->ln_number) | |
1191 | return -1; | |
1c0f4872 | 1192 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1193 | return 0; |
b3b94faa DT |
1194 | } |
1195 | ||
1196 | /** | |
1197 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1198 | * @num_gh: the number of structures | |
1199 | * @ghs: an array of struct gfs2_holder structures | |
1200 | * | |
1201 | * Returns: 0 on success (all glocks acquired), | |
1202 | * errno on failure (no glocks acquired) | |
1203 | */ | |
1204 | ||
1205 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1206 | struct gfs2_holder **p) | |
1207 | { | |
1208 | unsigned int x; | |
1209 | int error = 0; | |
1210 | ||
1211 | for (x = 0; x < num_gh; x++) | |
1212 | p[x] = &ghs[x]; | |
1213 | ||
1214 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1215 | ||
1216 | for (x = 0; x < num_gh; x++) { | |
1217 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1218 | ||
1219 | error = gfs2_glock_nq(p[x]); | |
1220 | if (error) { | |
1221 | while (x--) | |
1222 | gfs2_glock_dq(p[x]); | |
1223 | break; | |
1224 | } | |
1225 | } | |
1226 | ||
1227 | return error; | |
1228 | } | |
1229 | ||
1230 | /** | |
1231 | * gfs2_glock_nq_m - acquire multiple glocks | |
1232 | * @num_gh: the number of structures | |
1233 | * @ghs: an array of struct gfs2_holder structures | |
1234 | * | |
b3b94faa DT |
1235 | * |
1236 | * Returns: 0 on success (all glocks acquired), | |
1237 | * errno on failure (no glocks acquired) | |
1238 | */ | |
1239 | ||
1240 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1241 | { | |
eaf5bd3c SW |
1242 | struct gfs2_holder *tmp[4]; |
1243 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1244 | int error = 0; |
1245 | ||
eaf5bd3c SW |
1246 | switch(num_gh) { |
1247 | case 0: | |
b3b94faa | 1248 | return 0; |
eaf5bd3c | 1249 | case 1: |
b3b94faa DT |
1250 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1251 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1252 | default: |
1253 | if (num_gh <= 4) | |
b3b94faa | 1254 | break; |
eaf5bd3c SW |
1255 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1256 | if (!pph) | |
1257 | return -ENOMEM; | |
b3b94faa DT |
1258 | } |
1259 | ||
eaf5bd3c | 1260 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1261 | |
eaf5bd3c SW |
1262 | if (pph != tmp) |
1263 | kfree(pph); | |
b3b94faa DT |
1264 | |
1265 | return error; | |
1266 | } | |
1267 | ||
1268 | /** | |
1269 | * gfs2_glock_dq_m - release multiple glocks | |
1270 | * @num_gh: the number of structures | |
1271 | * @ghs: an array of struct gfs2_holder structures | |
1272 | * | |
1273 | */ | |
1274 | ||
1275 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1276 | { | |
fa1bbdea BP |
1277 | while (num_gh--) |
1278 | gfs2_glock_dq(&ghs[num_gh]); | |
b3b94faa DT |
1279 | } |
1280 | ||
f057f6cd | 1281 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
da755fdb | 1282 | { |
c4f68a13 BM |
1283 | unsigned long delay = 0; |
1284 | unsigned long holdtime; | |
1285 | unsigned long now = jiffies; | |
b3b94faa | 1286 | |
f057f6cd | 1287 | gfs2_glock_hold(gl); |
7cf8dcd3 BP |
1288 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
1289 | if (test_bit(GLF_QUEUED, &gl->gl_flags) && | |
1290 | gl->gl_name.ln_type == LM_TYPE_INODE) { | |
7b5e3d5f SW |
1291 | if (time_before(now, holdtime)) |
1292 | delay = holdtime - now; | |
1293 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) | |
7cf8dcd3 | 1294 | delay = gl->gl_hold_time; |
7b5e3d5f | 1295 | } |
b3b94faa | 1296 | |
6802e340 | 1297 | spin_lock(&gl->gl_spin); |
81ffbf65 | 1298 | handle_callback(gl, state, delay, true); |
6802e340 | 1299 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1300 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1301 | gfs2_glock_put(gl); | |
b3b94faa DT |
1302 | } |
1303 | ||
0809f6ec SW |
1304 | /** |
1305 | * gfs2_should_freeze - Figure out if glock should be frozen | |
1306 | * @gl: The glock in question | |
1307 | * | |
1308 | * Glocks are not frozen if (a) the result of the dlm operation is | |
1309 | * an error, (b) the locking operation was an unlock operation or | |
1310 | * (c) if there is a "noexp" flagged request anywhere in the queue | |
1311 | * | |
1312 | * Returns: 1 if freezing should occur, 0 otherwise | |
1313 | */ | |
1314 | ||
1315 | static int gfs2_should_freeze(const struct gfs2_glock *gl) | |
1316 | { | |
1317 | const struct gfs2_holder *gh; | |
1318 | ||
1319 | if (gl->gl_reply & ~LM_OUT_ST_MASK) | |
1320 | return 0; | |
1321 | if (gl->gl_target == LM_ST_UNLOCKED) | |
1322 | return 0; | |
1323 | ||
1324 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
1325 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1326 | continue; | |
1327 | if (LM_FLAG_NOEXP & gh->gh_flags) | |
1328 | return 0; | |
1329 | } | |
1330 | ||
1331 | return 1; | |
1332 | } | |
1333 | ||
b3b94faa | 1334 | /** |
f057f6cd SW |
1335 | * gfs2_glock_complete - Callback used by locking |
1336 | * @gl: Pointer to the glock | |
1337 | * @ret: The return value from the dlm | |
b3b94faa | 1338 | * |
47a25380 SW |
1339 | * The gl_reply field is under the gl_spin lock so that it is ok |
1340 | * to use a bitfield shared with other glock state fields. | |
b3b94faa DT |
1341 | */ |
1342 | ||
f057f6cd | 1343 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
b3b94faa | 1344 | { |
f057f6cd | 1345 | struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; |
0809f6ec | 1346 | |
47a25380 | 1347 | spin_lock(&gl->gl_spin); |
f057f6cd | 1348 | gl->gl_reply = ret; |
0809f6ec | 1349 | |
e0c2a9aa | 1350 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) { |
0809f6ec | 1351 | if (gfs2_should_freeze(gl)) { |
f057f6cd | 1352 | set_bit(GLF_FROZEN, &gl->gl_flags); |
0809f6ec | 1353 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1354 | return; |
0809f6ec | 1355 | } |
b3b94faa | 1356 | } |
47a25380 | 1357 | |
e66cf161 | 1358 | gl->gl_lockref.count++; |
f057f6cd | 1359 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
e66cf161 SW |
1360 | spin_unlock(&gl->gl_spin); |
1361 | ||
f057f6cd SW |
1362 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1363 | gfs2_glock_put(gl); | |
b3b94faa DT |
1364 | } |
1365 | ||
4506a519 SW |
1366 | static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) |
1367 | { | |
1368 | struct gfs2_glock *gla, *glb; | |
1369 | ||
1370 | gla = list_entry(a, struct gfs2_glock, gl_lru); | |
1371 | glb = list_entry(b, struct gfs2_glock, gl_lru); | |
1372 | ||
1373 | if (gla->gl_name.ln_number > glb->gl_name.ln_number) | |
1374 | return 1; | |
1375 | if (gla->gl_name.ln_number < glb->gl_name.ln_number) | |
1376 | return -1; | |
1377 | ||
1378 | return 0; | |
1379 | } | |
1380 | ||
1381 | /** | |
1382 | * gfs2_dispose_glock_lru - Demote a list of glocks | |
1383 | * @list: The list to dispose of | |
1384 | * | |
1385 | * Disposing of glocks may involve disk accesses, so that here we sort | |
1386 | * the glocks by number (i.e. disk location of the inodes) so that if | |
1387 | * there are any such accesses, they'll be sent in order (mostly). | |
1388 | * | |
1389 | * Must be called under the lru_lock, but may drop and retake this | |
1390 | * lock. While the lru_lock is dropped, entries may vanish from the | |
1391 | * list, but no new entries will appear on the list (since it is | |
1392 | * private) | |
1393 | */ | |
1394 | ||
1395 | static void gfs2_dispose_glock_lru(struct list_head *list) | |
1396 | __releases(&lru_lock) | |
1397 | __acquires(&lru_lock) | |
1398 | { | |
1399 | struct gfs2_glock *gl; | |
1400 | ||
1401 | list_sort(NULL, list, glock_cmp); | |
1402 | ||
1403 | while(!list_empty(list)) { | |
1404 | gl = list_entry(list->next, struct gfs2_glock, gl_lru); | |
1405 | list_del_init(&gl->gl_lru); | |
e66cf161 SW |
1406 | if (!spin_trylock(&gl->gl_spin)) { |
1407 | list_add(&gl->gl_lru, &lru_list); | |
1408 | atomic_inc(&lru_count); | |
1409 | continue; | |
1410 | } | |
4506a519 | 1411 | clear_bit(GLF_LRU, &gl->gl_flags); |
4506a519 | 1412 | spin_unlock(&lru_lock); |
e66cf161 | 1413 | gl->gl_lockref.count++; |
4506a519 | 1414 | if (demote_ok(gl)) |
81ffbf65 | 1415 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
4506a519 | 1416 | WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); |
4506a519 | 1417 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 1418 | gl->gl_lockref.count--; |
4506a519 SW |
1419 | spin_unlock(&gl->gl_spin); |
1420 | spin_lock(&lru_lock); | |
1421 | } | |
1422 | } | |
1423 | ||
2a005855 SW |
1424 | /** |
1425 | * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote | |
1426 | * @nr: The number of entries to scan | |
1427 | * | |
4506a519 SW |
1428 | * This function selects the entries on the LRU which are able to |
1429 | * be demoted, and then kicks off the process by calling | |
1430 | * gfs2_dispose_glock_lru() above. | |
2a005855 | 1431 | */ |
b3b94faa | 1432 | |
1ab6c499 | 1433 | static long gfs2_scan_glock_lru(int nr) |
b3b94faa DT |
1434 | { |
1435 | struct gfs2_glock *gl; | |
97cc1025 | 1436 | LIST_HEAD(skipped); |
4506a519 | 1437 | LIST_HEAD(dispose); |
1ab6c499 | 1438 | long freed = 0; |
b3b94faa | 1439 | |
97cc1025 | 1440 | spin_lock(&lru_lock); |
1ab6c499 | 1441 | while ((nr-- >= 0) && !list_empty(&lru_list)) { |
97cc1025 | 1442 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); |
97cc1025 SW |
1443 | |
1444 | /* Test for being demotable */ | |
1445 | if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { | |
4506a519 SW |
1446 | list_move(&gl->gl_lru, &dispose); |
1447 | atomic_dec(&lru_count); | |
1ab6c499 | 1448 | freed++; |
2163b1e6 | 1449 | continue; |
97cc1025 | 1450 | } |
4506a519 SW |
1451 | |
1452 | list_move(&gl->gl_lru, &skipped); | |
b3b94faa | 1453 | } |
97cc1025 | 1454 | list_splice(&skipped, &lru_list); |
4506a519 SW |
1455 | if (!list_empty(&dispose)) |
1456 | gfs2_dispose_glock_lru(&dispose); | |
97cc1025 | 1457 | spin_unlock(&lru_lock); |
1ab6c499 DC |
1458 | |
1459 | return freed; | |
2a005855 SW |
1460 | } |
1461 | ||
1ab6c499 DC |
1462 | static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink, |
1463 | struct shrink_control *sc) | |
2a005855 | 1464 | { |
1ab6c499 DC |
1465 | if (!(sc->gfp_mask & __GFP_FS)) |
1466 | return SHRINK_STOP; | |
1467 | return gfs2_scan_glock_lru(sc->nr_to_scan); | |
1468 | } | |
2a005855 | 1469 | |
1ab6c499 DC |
1470 | static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink, |
1471 | struct shrink_control *sc) | |
1472 | { | |
55f841ce | 1473 | return vfs_pressure_ratio(atomic_read(&lru_count)); |
b3b94faa DT |
1474 | } |
1475 | ||
97cc1025 | 1476 | static struct shrinker glock_shrinker = { |
97cc1025 | 1477 | .seeks = DEFAULT_SEEKS, |
1ab6c499 DC |
1478 | .count_objects = gfs2_glock_shrink_count, |
1479 | .scan_objects = gfs2_glock_shrink_scan, | |
97cc1025 SW |
1480 | }; |
1481 | ||
b3b94faa DT |
1482 | /** |
1483 | * examine_bucket - Call a function for glock in a hash bucket | |
1484 | * @examiner: the function | |
1485 | * @sdp: the filesystem | |
1486 | * @bucket: the bucket | |
1487 | * | |
b3b94faa DT |
1488 | */ |
1489 | ||
bc015cb8 | 1490 | static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, |
37b2fa6a | 1491 | unsigned int hash) |
b3b94faa | 1492 | { |
bc015cb8 SW |
1493 | struct gfs2_glock *gl; |
1494 | struct hlist_bl_head *head = &gl_hash_table[hash]; | |
1495 | struct hlist_bl_node *pos; | |
b3b94faa | 1496 | |
bc015cb8 SW |
1497 | rcu_read_lock(); |
1498 | hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { | |
e66cf161 | 1499 | if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref)) |
24264434 | 1500 | examiner(gl); |
b3b94faa | 1501 | } |
bc015cb8 | 1502 | rcu_read_unlock(); |
8fbbfd21 | 1503 | cond_resched(); |
bc015cb8 SW |
1504 | } |
1505 | ||
1506 | static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp) | |
1507 | { | |
1508 | unsigned x; | |
1509 | ||
1510 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
1511 | examine_bucket(examiner, sdp, x); | |
b3b94faa DT |
1512 | } |
1513 | ||
f057f6cd SW |
1514 | |
1515 | /** | |
1516 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting | |
1517 | * @gl: The glock to thaw | |
1518 | * | |
f057f6cd SW |
1519 | */ |
1520 | ||
1521 | static void thaw_glock(struct gfs2_glock *gl) | |
1522 | { | |
1523 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
7286b31e | 1524 | goto out; |
f057f6cd | 1525 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
7286b31e SW |
1526 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) { |
1527 | out: | |
f057f6cd | 1528 | gfs2_glock_put(gl); |
7286b31e | 1529 | } |
f057f6cd SW |
1530 | } |
1531 | ||
b3b94faa DT |
1532 | /** |
1533 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1534 | * @gl: the glock to look at | |
1535 | * | |
1536 | */ | |
1537 | ||
1538 | static void clear_glock(struct gfs2_glock *gl) | |
1539 | { | |
f42ab085 | 1540 | gfs2_glock_remove_from_lru(gl); |
b3b94faa | 1541 | |
6802e340 | 1542 | spin_lock(&gl->gl_spin); |
c741c455 | 1543 | if (gl->gl_state != LM_ST_UNLOCKED) |
81ffbf65 | 1544 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
6802e340 | 1545 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1546 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1547 | gfs2_glock_put(gl); | |
b3b94faa DT |
1548 | } |
1549 | ||
f057f6cd SW |
1550 | /** |
1551 | * gfs2_glock_thaw - Thaw any frozen glocks | |
1552 | * @sdp: The super block | |
1553 | * | |
1554 | */ | |
1555 | ||
1556 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) | |
1557 | { | |
bc015cb8 SW |
1558 | glock_hash_walk(thaw_glock, sdp); |
1559 | } | |
f057f6cd | 1560 | |
ac3beb6a | 1561 | static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
bc015cb8 | 1562 | { |
bc015cb8 | 1563 | spin_lock(&gl->gl_spin); |
ac3beb6a | 1564 | gfs2_dump_glock(seq, gl); |
bc015cb8 | 1565 | spin_unlock(&gl->gl_spin); |
bc015cb8 SW |
1566 | } |
1567 | ||
1568 | static void dump_glock_func(struct gfs2_glock *gl) | |
1569 | { | |
1570 | dump_glock(NULL, gl); | |
f057f6cd SW |
1571 | } |
1572 | ||
b3b94faa DT |
1573 | /** |
1574 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1575 | * @sdp: the filesystem | |
1576 | * @wait: wait until it's all gone | |
1577 | * | |
1bdad606 | 1578 | * Called when unmounting the filesystem. |
b3b94faa DT |
1579 | */ |
1580 | ||
fefc03bf | 1581 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa | 1582 | { |
fb6791d1 | 1583 | set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags); |
222cb538 | 1584 | flush_workqueue(glock_workqueue); |
bc015cb8 | 1585 | glock_hash_walk(clear_glock, sdp); |
8f05228e SW |
1586 | flush_workqueue(glock_workqueue); |
1587 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); | |
bc015cb8 | 1588 | glock_hash_walk(dump_glock_func, sdp); |
b3b94faa DT |
1589 | } |
1590 | ||
813e0c46 SW |
1591 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1592 | { | |
1593 | struct gfs2_glock *gl = ip->i_gl; | |
1594 | int ret; | |
1595 | ||
1596 | ret = gfs2_truncatei_resume(ip); | |
1597 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); | |
1598 | ||
1599 | spin_lock(&gl->gl_spin); | |
1600 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1601 | run_queue(gl, 1); | |
1602 | spin_unlock(&gl->gl_spin); | |
1603 | } | |
1604 | ||
6802e340 | 1605 | static const char *state2str(unsigned state) |
04b933f2 | 1606 | { |
6802e340 SW |
1607 | switch(state) { |
1608 | case LM_ST_UNLOCKED: | |
1609 | return "UN"; | |
1610 | case LM_ST_SHARED: | |
1611 | return "SH"; | |
1612 | case LM_ST_DEFERRED: | |
1613 | return "DF"; | |
1614 | case LM_ST_EXCLUSIVE: | |
1615 | return "EX"; | |
1616 | } | |
1617 | return "??"; | |
1618 | } | |
1619 | ||
1620 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1621 | { | |
1622 | char *p = buf; | |
1623 | if (flags & LM_FLAG_TRY) | |
1624 | *p++ = 't'; | |
1625 | if (flags & LM_FLAG_TRY_1CB) | |
1626 | *p++ = 'T'; | |
1627 | if (flags & LM_FLAG_NOEXP) | |
1628 | *p++ = 'e'; | |
1629 | if (flags & LM_FLAG_ANY) | |
f057f6cd | 1630 | *p++ = 'A'; |
6802e340 SW |
1631 | if (flags & LM_FLAG_PRIORITY) |
1632 | *p++ = 'p'; | |
1633 | if (flags & GL_ASYNC) | |
1634 | *p++ = 'a'; | |
1635 | if (flags & GL_EXACT) | |
1636 | *p++ = 'E'; | |
6802e340 SW |
1637 | if (flags & GL_NOCACHE) |
1638 | *p++ = 'c'; | |
1639 | if (test_bit(HIF_HOLDER, &iflags)) | |
1640 | *p++ = 'H'; | |
1641 | if (test_bit(HIF_WAIT, &iflags)) | |
1642 | *p++ = 'W'; | |
1643 | if (test_bit(HIF_FIRST, &iflags)) | |
1644 | *p++ = 'F'; | |
1645 | *p = 0; | |
1646 | return buf; | |
04b933f2 RP |
1647 | } |
1648 | ||
b3b94faa DT |
1649 | /** |
1650 | * dump_holder - print information about a glock holder | |
6802e340 | 1651 | * @seq: the seq_file struct |
b3b94faa DT |
1652 | * @gh: the glock holder |
1653 | * | |
b3b94faa DT |
1654 | */ |
1655 | ||
ac3beb6a | 1656 | static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1657 | { |
6802e340 | 1658 | struct task_struct *gh_owner = NULL; |
6802e340 | 1659 | char flags_buf[32]; |
b3b94faa | 1660 | |
0b3a2c99 | 1661 | rcu_read_lock(); |
6802e340 | 1662 | if (gh->gh_owner_pid) |
b1e058da | 1663 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
cc18152e JP |
1664 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
1665 | state2str(gh->gh_state), | |
1666 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1667 | gh->gh_error, | |
1668 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1669 | gh_owner ? gh_owner->comm : "(ended)", | |
1670 | (void *)gh->gh_ip); | |
0b3a2c99 | 1671 | rcu_read_unlock(); |
b3b94faa DT |
1672 | } |
1673 | ||
627c10b7 | 1674 | static const char *gflags2str(char *buf, const struct gfs2_glock *gl) |
6802e340 | 1675 | { |
627c10b7 | 1676 | const unsigned long *gflags = &gl->gl_flags; |
6802e340 | 1677 | char *p = buf; |
627c10b7 | 1678 | |
6802e340 SW |
1679 | if (test_bit(GLF_LOCK, gflags)) |
1680 | *p++ = 'l'; | |
6802e340 SW |
1681 | if (test_bit(GLF_DEMOTE, gflags)) |
1682 | *p++ = 'D'; | |
1683 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1684 | *p++ = 'd'; | |
1685 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1686 | *p++ = 'p'; | |
1687 | if (test_bit(GLF_DIRTY, gflags)) | |
1688 | *p++ = 'y'; | |
1689 | if (test_bit(GLF_LFLUSH, gflags)) | |
1690 | *p++ = 'f'; | |
1691 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1692 | *p++ = 'i'; | |
1693 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1694 | *p++ = 'r'; | |
f057f6cd | 1695 | if (test_bit(GLF_INITIAL, gflags)) |
d8348de0 | 1696 | *p++ = 'I'; |
f057f6cd SW |
1697 | if (test_bit(GLF_FROZEN, gflags)) |
1698 | *p++ = 'F'; | |
7b5e3d5f SW |
1699 | if (test_bit(GLF_QUEUED, gflags)) |
1700 | *p++ = 'q'; | |
627c10b7 SW |
1701 | if (test_bit(GLF_LRU, gflags)) |
1702 | *p++ = 'L'; | |
1703 | if (gl->gl_object) | |
1704 | *p++ = 'o'; | |
a245769f SW |
1705 | if (test_bit(GLF_BLOCKING, gflags)) |
1706 | *p++ = 'b'; | |
6802e340 SW |
1707 | *p = 0; |
1708 | return buf; | |
b3b94faa DT |
1709 | } |
1710 | ||
1711 | /** | |
8eae1ca0 | 1712 | * gfs2_dump_glock - print information about a glock |
6802e340 | 1713 | * @seq: The seq_file struct |
b3b94faa | 1714 | * @gl: the glock |
6802e340 SW |
1715 | * |
1716 | * The file format is as follows: | |
1717 | * One line per object, capital letters are used to indicate objects | |
1718 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1719 | * other objects are indented by a single space and follow the glock to | |
1720 | * which they are related. Fields are indicated by lower case letters | |
1721 | * followed by a colon and the field value, except for strings which are in | |
1722 | * [] so that its possible to see if they are composed of spaces for | |
1723 | * example. The field's are n = number (id of the object), f = flags, | |
1724 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa | 1725 | * |
b3b94faa DT |
1726 | */ |
1727 | ||
ac3beb6a | 1728 | void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1729 | { |
6802e340 SW |
1730 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1731 | unsigned long long dtime; | |
1732 | const struct gfs2_holder *gh; | |
1733 | char gflags_buf[32]; | |
b3b94faa | 1734 | |
6802e340 SW |
1735 | dtime = jiffies - gl->gl_demote_time; |
1736 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1737 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1738 | dtime = 0; | |
7cf8dcd3 | 1739 | gfs2_print_dbg(seq, "G: s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d v:%d r:%d m:%ld\n", |
6802e340 SW |
1740 | state2str(gl->gl_state), |
1741 | gl->gl_name.ln_type, | |
1742 | (unsigned long long)gl->gl_name.ln_number, | |
627c10b7 | 1743 | gflags2str(gflags_buf, gl), |
6802e340 SW |
1744 | state2str(gl->gl_target), |
1745 | state2str(gl->gl_demote_state), dtime, | |
6802e340 | 1746 | atomic_read(&gl->gl_ail_count), |
f42ab085 | 1747 | atomic_read(&gl->gl_revokes), |
e66cf161 | 1748 | (int)gl->gl_lockref.count, gl->gl_hold_time); |
b3b94faa | 1749 | |
ac3beb6a SW |
1750 | list_for_each_entry(gh, &gl->gl_holders, gh_list) |
1751 | dump_holder(seq, gh); | |
1752 | ||
6802e340 | 1753 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
ac3beb6a | 1754 | glops->go_dump(seq, gl); |
b3b94faa DT |
1755 | } |
1756 | ||
a245769f SW |
1757 | static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr) |
1758 | { | |
1759 | struct gfs2_glock *gl = iter_ptr; | |
1760 | ||
1761 | seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n", | |
1762 | gl->gl_name.ln_type, | |
1763 | (unsigned long long)gl->gl_name.ln_number, | |
1764 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTT], | |
1765 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR], | |
1766 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB], | |
1767 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB], | |
1768 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRT], | |
1769 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR], | |
1770 | (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT], | |
1771 | (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]); | |
1772 | return 0; | |
1773 | } | |
1774 | ||
1775 | static const char *gfs2_gltype[] = { | |
1776 | "type", | |
1777 | "reserved", | |
1778 | "nondisk", | |
1779 | "inode", | |
1780 | "rgrp", | |
1781 | "meta", | |
1782 | "iopen", | |
1783 | "flock", | |
1784 | "plock", | |
1785 | "quota", | |
1786 | "journal", | |
1787 | }; | |
1788 | ||
1789 | static const char *gfs2_stype[] = { | |
1790 | [GFS2_LKS_SRTT] = "srtt", | |
1791 | [GFS2_LKS_SRTTVAR] = "srttvar", | |
1792 | [GFS2_LKS_SRTTB] = "srttb", | |
1793 | [GFS2_LKS_SRTTVARB] = "srttvarb", | |
1794 | [GFS2_LKS_SIRT] = "sirt", | |
1795 | [GFS2_LKS_SIRTVAR] = "sirtvar", | |
1796 | [GFS2_LKS_DCOUNT] = "dlm", | |
1797 | [GFS2_LKS_QCOUNT] = "queue", | |
1798 | }; | |
1799 | ||
1800 | #define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype)) | |
1801 | ||
1802 | static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr) | |
1803 | { | |
1804 | struct gfs2_glock_iter *gi = seq->private; | |
1805 | struct gfs2_sbd *sdp = gi->sdp; | |
1806 | unsigned index = gi->hash >> 3; | |
1807 | unsigned subindex = gi->hash & 0x07; | |
1808 | s64 value; | |
1809 | int i; | |
1810 | ||
1811 | if (index == 0 && subindex != 0) | |
1812 | return 0; | |
6802e340 | 1813 | |
a245769f SW |
1814 | seq_printf(seq, "%-10s %8s:", gfs2_gltype[index], |
1815 | (index == 0) ? "cpu": gfs2_stype[subindex]); | |
b3b94faa | 1816 | |
a245769f SW |
1817 | for_each_possible_cpu(i) { |
1818 | const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i); | |
1819 | if (index == 0) { | |
1820 | value = i; | |
1821 | } else { | |
1822 | value = lkstats->lkstats[index - 1].stats[subindex]; | |
1823 | } | |
1824 | seq_printf(seq, " %15lld", (long long)value); | |
1825 | } | |
1826 | seq_putc(seq, '\n'); | |
1827 | return 0; | |
1828 | } | |
8fbbfd21 | 1829 | |
85d1da67 SW |
1830 | int __init gfs2_glock_init(void) |
1831 | { | |
1832 | unsigned i; | |
1833 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
bc015cb8 | 1834 | INIT_HLIST_BL_HEAD(&gl_hash_table[i]); |
087efdd3 | 1835 | } |
8fbbfd21 | 1836 | |
d2115778 | 1837 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
58a69cb4 | 1838 | WQ_HIGHPRI | WQ_FREEZABLE, 0); |
dfc4616d DC |
1839 | if (!glock_workqueue) |
1840 | return -ENOMEM; | |
d2115778 | 1841 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
58a69cb4 | 1842 | WQ_MEM_RECLAIM | WQ_FREEZABLE, |
d2115778 | 1843 | 0); |
dfc4616d | 1844 | if (!gfs2_delete_workqueue) { |
b94a170e | 1845 | destroy_workqueue(glock_workqueue); |
dfc4616d | 1846 | return -ENOMEM; |
b94a170e | 1847 | } |
97cc1025 SW |
1848 | |
1849 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1850 | |
85d1da67 SW |
1851 | return 0; |
1852 | } | |
1853 | ||
8fbbfd21 SW |
1854 | void gfs2_glock_exit(void) |
1855 | { | |
97cc1025 | 1856 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1857 | destroy_workqueue(glock_workqueue); |
b94a170e | 1858 | destroy_workqueue(gfs2_delete_workqueue); |
8fbbfd21 SW |
1859 | } |
1860 | ||
bc015cb8 SW |
1861 | static inline struct gfs2_glock *glock_hash_chain(unsigned hash) |
1862 | { | |
1863 | return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]), | |
1864 | struct gfs2_glock, gl_list); | |
1865 | } | |
1866 | ||
1867 | static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl) | |
1868 | { | |
7e32d026 | 1869 | return hlist_bl_entry(rcu_dereference(gl->gl_list.next), |
bc015cb8 SW |
1870 | struct gfs2_glock, gl_list); |
1871 | } | |
1872 | ||
6802e340 | 1873 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1874 | { |
7b08fc62 SW |
1875 | struct gfs2_glock *gl; |
1876 | ||
bc015cb8 SW |
1877 | do { |
1878 | gl = gi->gl; | |
1879 | if (gl) { | |
1880 | gi->gl = glock_hash_next(gl); | |
ba1ddcb6 | 1881 | gi->nhash++; |
bc015cb8 | 1882 | } else { |
ba1ddcb6 SW |
1883 | if (gi->hash >= GFS2_GL_HASH_SIZE) { |
1884 | rcu_read_unlock(); | |
1885 | return 1; | |
1886 | } | |
bc015cb8 | 1887 | gi->gl = glock_hash_chain(gi->hash); |
ba1ddcb6 | 1888 | gi->nhash = 0; |
bc015cb8 SW |
1889 | } |
1890 | while (gi->gl == NULL) { | |
1891 | gi->hash++; | |
1892 | if (gi->hash >= GFS2_GL_HASH_SIZE) { | |
1893 | rcu_read_unlock(); | |
1894 | return 1; | |
1895 | } | |
1896 | gi->gl = glock_hash_chain(gi->hash); | |
ba1ddcb6 | 1897 | gi->nhash = 0; |
bc015cb8 SW |
1898 | } |
1899 | /* Skip entries for other sb and dead entries */ | |
e3c4269d MN |
1900 | } while (gi->sdp != gi->gl->gl_sbd || |
1901 | __lockref_is_dead(&gi->gl->gl_lockref)); | |
a947e033 | 1902 | |
7c52b166 RP |
1903 | return 0; |
1904 | } | |
1905 | ||
6802e340 | 1906 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1907 | { |
6802e340 | 1908 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1909 | loff_t n = *pos; |
1910 | ||
ba1ddcb6 SW |
1911 | if (gi->last_pos <= *pos) |
1912 | n = gi->nhash + (*pos - gi->last_pos); | |
1913 | else | |
1914 | gi->hash = 0; | |
1915 | ||
1916 | gi->nhash = 0; | |
bc015cb8 | 1917 | rcu_read_lock(); |
7c52b166 | 1918 | |
6802e340 | 1919 | do { |
bc015cb8 | 1920 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1921 | return NULL; |
6802e340 | 1922 | } while (n--); |
7c52b166 | 1923 | |
ba1ddcb6 | 1924 | gi->last_pos = *pos; |
6802e340 | 1925 | return gi->gl; |
7c52b166 RP |
1926 | } |
1927 | ||
6802e340 | 1928 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1929 | loff_t *pos) |
1930 | { | |
6802e340 | 1931 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1932 | |
1933 | (*pos)++; | |
ba1ddcb6 | 1934 | gi->last_pos = *pos; |
bc015cb8 | 1935 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1936 | return NULL; |
7c52b166 | 1937 | |
6802e340 | 1938 | return gi->gl; |
7c52b166 RP |
1939 | } |
1940 | ||
6802e340 | 1941 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1942 | { |
6802e340 | 1943 | struct gfs2_glock_iter *gi = seq->private; |
bc015cb8 SW |
1944 | |
1945 | if (gi->gl) | |
1946 | rcu_read_unlock(); | |
1947 | gi->gl = NULL; | |
7c52b166 RP |
1948 | } |
1949 | ||
6802e340 | 1950 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1951 | { |
ac3beb6a SW |
1952 | dump_glock(seq, iter_ptr); |
1953 | return 0; | |
7c52b166 RP |
1954 | } |
1955 | ||
a245769f SW |
1956 | static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos) |
1957 | { | |
1958 | struct gfs2_glock_iter *gi = seq->private; | |
1959 | ||
1960 | gi->hash = *pos; | |
1961 | if (*pos >= GFS2_NR_SBSTATS) | |
1962 | return NULL; | |
1963 | preempt_disable(); | |
1964 | return SEQ_START_TOKEN; | |
1965 | } | |
1966 | ||
1967 | static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr, | |
1968 | loff_t *pos) | |
1969 | { | |
1970 | struct gfs2_glock_iter *gi = seq->private; | |
1971 | (*pos)++; | |
1972 | gi->hash++; | |
1973 | if (gi->hash >= GFS2_NR_SBSTATS) { | |
1974 | preempt_enable(); | |
1975 | return NULL; | |
1976 | } | |
1977 | return SEQ_START_TOKEN; | |
1978 | } | |
1979 | ||
1980 | static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr) | |
1981 | { | |
1982 | preempt_enable(); | |
1983 | } | |
1984 | ||
4ef29002 | 1985 | static const struct seq_operations gfs2_glock_seq_ops = { |
7c52b166 RP |
1986 | .start = gfs2_glock_seq_start, |
1987 | .next = gfs2_glock_seq_next, | |
1988 | .stop = gfs2_glock_seq_stop, | |
1989 | .show = gfs2_glock_seq_show, | |
1990 | }; | |
1991 | ||
a245769f SW |
1992 | static const struct seq_operations gfs2_glstats_seq_ops = { |
1993 | .start = gfs2_glock_seq_start, | |
1994 | .next = gfs2_glock_seq_next, | |
1995 | .stop = gfs2_glock_seq_stop, | |
1996 | .show = gfs2_glstats_seq_show, | |
1997 | }; | |
1998 | ||
1999 | static const struct seq_operations gfs2_sbstats_seq_ops = { | |
2000 | .start = gfs2_sbstats_seq_start, | |
2001 | .next = gfs2_sbstats_seq_next, | |
2002 | .stop = gfs2_sbstats_seq_stop, | |
2003 | .show = gfs2_sbstats_seq_show, | |
2004 | }; | |
2005 | ||
0fe2f1e9 SW |
2006 | #define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL) |
2007 | ||
a245769f | 2008 | static int gfs2_glocks_open(struct inode *inode, struct file *file) |
7c52b166 | 2009 | { |
6802e340 SW |
2010 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
2011 | sizeof(struct gfs2_glock_iter)); | |
2012 | if (ret == 0) { | |
2013 | struct seq_file *seq = file->private_data; | |
2014 | struct gfs2_glock_iter *gi = seq->private; | |
2015 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 2016 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 2017 | if (seq->buf) |
0fe2f1e9 | 2018 | seq->size = GFS2_SEQ_GOODSIZE; |
6802e340 SW |
2019 | } |
2020 | return ret; | |
7c52b166 RP |
2021 | } |
2022 | ||
a245769f SW |
2023 | static int gfs2_glstats_open(struct inode *inode, struct file *file) |
2024 | { | |
2025 | int ret = seq_open_private(file, &gfs2_glstats_seq_ops, | |
2026 | sizeof(struct gfs2_glock_iter)); | |
2027 | if (ret == 0) { | |
2028 | struct seq_file *seq = file->private_data; | |
2029 | struct gfs2_glock_iter *gi = seq->private; | |
2030 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 2031 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 2032 | if (seq->buf) |
0fe2f1e9 | 2033 | seq->size = GFS2_SEQ_GOODSIZE; |
a245769f SW |
2034 | } |
2035 | return ret; | |
2036 | } | |
2037 | ||
2038 | static int gfs2_sbstats_open(struct inode *inode, struct file *file) | |
2039 | { | |
2040 | int ret = seq_open_private(file, &gfs2_sbstats_seq_ops, | |
2041 | sizeof(struct gfs2_glock_iter)); | |
2042 | if (ret == 0) { | |
2043 | struct seq_file *seq = file->private_data; | |
2044 | struct gfs2_glock_iter *gi = seq->private; | |
2045 | gi->sdp = inode->i_private; | |
2046 | } | |
2047 | return ret; | |
2048 | } | |
2049 | ||
2050 | static const struct file_operations gfs2_glocks_fops = { | |
2051 | .owner = THIS_MODULE, | |
2052 | .open = gfs2_glocks_open, | |
2053 | .read = seq_read, | |
2054 | .llseek = seq_lseek, | |
2055 | .release = seq_release_private, | |
2056 | }; | |
2057 | ||
2058 | static const struct file_operations gfs2_glstats_fops = { | |
7c52b166 | 2059 | .owner = THIS_MODULE, |
a245769f SW |
2060 | .open = gfs2_glstats_open, |
2061 | .read = seq_read, | |
2062 | .llseek = seq_lseek, | |
2063 | .release = seq_release_private, | |
2064 | }; | |
2065 | ||
2066 | static const struct file_operations gfs2_sbstats_fops = { | |
2067 | .owner = THIS_MODULE, | |
2068 | .open = gfs2_sbstats_open, | |
7c52b166 RP |
2069 | .read = seq_read, |
2070 | .llseek = seq_lseek, | |
6802e340 | 2071 | .release = seq_release_private, |
7c52b166 RP |
2072 | }; |
2073 | ||
2074 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
2075 | { | |
5f882096 RP |
2076 | sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root); |
2077 | if (!sdp->debugfs_dir) | |
2078 | return -ENOMEM; | |
2079 | sdp->debugfs_dentry_glocks = debugfs_create_file("glocks", | |
2080 | S_IFREG | S_IRUGO, | |
2081 | sdp->debugfs_dir, sdp, | |
a245769f | 2082 | &gfs2_glocks_fops); |
5f882096 | 2083 | if (!sdp->debugfs_dentry_glocks) |
a245769f SW |
2084 | goto fail; |
2085 | ||
2086 | sdp->debugfs_dentry_glstats = debugfs_create_file("glstats", | |
2087 | S_IFREG | S_IRUGO, | |
2088 | sdp->debugfs_dir, sdp, | |
2089 | &gfs2_glstats_fops); | |
2090 | if (!sdp->debugfs_dentry_glstats) | |
2091 | goto fail; | |
2092 | ||
2093 | sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats", | |
2094 | S_IFREG | S_IRUGO, | |
2095 | sdp->debugfs_dir, sdp, | |
2096 | &gfs2_sbstats_fops); | |
2097 | if (!sdp->debugfs_dentry_sbstats) | |
2098 | goto fail; | |
7c52b166 RP |
2099 | |
2100 | return 0; | |
a245769f SW |
2101 | fail: |
2102 | gfs2_delete_debugfs_file(sdp); | |
2103 | return -ENOMEM; | |
7c52b166 RP |
2104 | } |
2105 | ||
2106 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) | |
2107 | { | |
a245769f | 2108 | if (sdp->debugfs_dir) { |
5f882096 RP |
2109 | if (sdp->debugfs_dentry_glocks) { |
2110 | debugfs_remove(sdp->debugfs_dentry_glocks); | |
2111 | sdp->debugfs_dentry_glocks = NULL; | |
2112 | } | |
a245769f SW |
2113 | if (sdp->debugfs_dentry_glstats) { |
2114 | debugfs_remove(sdp->debugfs_dentry_glstats); | |
2115 | sdp->debugfs_dentry_glstats = NULL; | |
2116 | } | |
2117 | if (sdp->debugfs_dentry_sbstats) { | |
2118 | debugfs_remove(sdp->debugfs_dentry_sbstats); | |
2119 | sdp->debugfs_dentry_sbstats = NULL; | |
2120 | } | |
5f882096 RP |
2121 | debugfs_remove(sdp->debugfs_dir); |
2122 | sdp->debugfs_dir = NULL; | |
2123 | } | |
7c52b166 RP |
2124 | } |
2125 | ||
2126 | int gfs2_register_debugfs(void) | |
2127 | { | |
2128 | gfs2_root = debugfs_create_dir("gfs2", NULL); | |
2129 | return gfs2_root ? 0 : -ENOMEM; | |
2130 | } | |
2131 | ||
2132 | void gfs2_unregister_debugfs(void) | |
2133 | { | |
2134 | debugfs_remove(gfs2_root); | |
5f882096 | 2135 | gfs2_root = NULL; |
7c52b166 | 2136 | } |