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); | |
4e857c58 | 280 | smp_mb__after_atomic(); |
6802e340 SW |
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); | |
4e857c58 | 414 | smp_mb__after_atomic(); |
6802e340 SW |
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 | 622 | clear_bit(GLF_LOCK, &gl->gl_flags); |
4e857c58 | 623 | smp_mb__after_atomic(); |
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); |
4e857c58 | 631 | smp_mb__after_atomic(); |
7e71c55e | 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 | 733 | cachep = gfs2_glock_cachep; |
fe0bbd29 | 734 | gl = kmem_cache_alloc(cachep, GFP_NOFS); |
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) { | |
fe0bbd29 | 741 | gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_NOFS); |
4e2f8849 | 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; | |
d29c0afe | 814 | gh->gh_ip = _RET_IP_; |
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; |
d29c0afe | 838 | gh->gh_ip = _RET_IP_; |
30badc95 | 839 | put_pid(gh->gh_owner_pid); |
1a0eae88 | 840 | gh->gh_owner_pid = get_pid(task_pid(current)); |
b3b94faa DT |
841 | } |
842 | ||
843 | /** | |
844 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
845 | * @gh: the holder structure | |
846 | * | |
847 | */ | |
848 | ||
849 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
850 | { | |
b1e058da | 851 | put_pid(gh->gh_owner_pid); |
b3b94faa DT |
852 | gfs2_glock_put(gh->gh_gl); |
853 | gh->gh_gl = NULL; | |
d0dc80db | 854 | gh->gh_ip = 0; |
b3b94faa DT |
855 | } |
856 | ||
07a79049 BP |
857 | /** |
858 | * gfs2_glock_wait - wait on a glock acquisition | |
859 | * @gh: the glock holder | |
860 | * | |
861 | * Returns: 0 on success | |
862 | */ | |
863 | ||
864 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
da755fdb | 865 | { |
7cf8dcd3 BP |
866 | unsigned long time1 = jiffies; |
867 | ||
6802e340 | 868 | might_sleep(); |
74316201 | 869 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE); |
7cf8dcd3 BP |
870 | if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */ |
871 | /* Lengthen the minimum hold time. */ | |
872 | gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time + | |
873 | GL_GLOCK_HOLD_INCR, | |
874 | GL_GLOCK_MAX_HOLD); | |
07a79049 | 875 | return gh->gh_error; |
da755fdb SW |
876 | } |
877 | ||
b3b94faa | 878 | /** |
6802e340 SW |
879 | * handle_callback - process a demote request |
880 | * @gl: the glock | |
881 | * @state: the state the caller wants us to change to | |
b3b94faa | 882 | * |
6802e340 SW |
883 | * There are only two requests that we are going to see in actual |
884 | * practise: LM_ST_SHARED and LM_ST_UNLOCKED | |
b3b94faa DT |
885 | */ |
886 | ||
6802e340 | 887 | static void handle_callback(struct gfs2_glock *gl, unsigned int state, |
81ffbf65 | 888 | unsigned long delay, bool remote) |
b3b94faa | 889 | { |
6802e340 | 890 | int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE; |
b3b94faa | 891 | |
6802e340 SW |
892 | set_bit(bit, &gl->gl_flags); |
893 | if (gl->gl_demote_state == LM_ST_EXCLUSIVE) { | |
894 | gl->gl_demote_state = state; | |
895 | gl->gl_demote_time = jiffies; | |
6802e340 SW |
896 | } else if (gl->gl_demote_state != LM_ST_UNLOCKED && |
897 | gl->gl_demote_state != state) { | |
898 | gl->gl_demote_state = LM_ST_UNLOCKED; | |
b3b94faa | 899 | } |
b94a170e | 900 | if (gl->gl_ops->go_callback) |
81ffbf65 | 901 | gl->gl_ops->go_callback(gl, remote); |
7bd8b2eb | 902 | trace_gfs2_demote_rq(gl, remote); |
b3b94faa DT |
903 | } |
904 | ||
6802e340 | 905 | void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) |
7c52b166 | 906 | { |
5e69069c | 907 | struct va_format vaf; |
7c52b166 RP |
908 | va_list args; |
909 | ||
910 | va_start(args, fmt); | |
5e69069c | 911 | |
6802e340 | 912 | if (seq) { |
1bb49303 | 913 | seq_vprintf(seq, fmt, args); |
6802e340 | 914 | } else { |
5e69069c JP |
915 | vaf.fmt = fmt; |
916 | vaf.va = &args; | |
917 | ||
d77d1b58 | 918 | pr_err("%pV", &vaf); |
6802e340 | 919 | } |
5e69069c | 920 | |
7c52b166 RP |
921 | va_end(args); |
922 | } | |
923 | ||
b3b94faa DT |
924 | /** |
925 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
926 | * @gh: the holder structure to add | |
927 | * | |
6802e340 SW |
928 | * Eventually we should move the recursive locking trap to a |
929 | * debugging option or something like that. This is the fast | |
930 | * path and needs to have the minimum number of distractions. | |
931 | * | |
b3b94faa DT |
932 | */ |
933 | ||
6802e340 | 934 | static inline void add_to_queue(struct gfs2_holder *gh) |
55ba474d HH |
935 | __releases(&gl->gl_spin) |
936 | __acquires(&gl->gl_spin) | |
b3b94faa DT |
937 | { |
938 | struct gfs2_glock *gl = gh->gh_gl; | |
6802e340 SW |
939 | struct gfs2_sbd *sdp = gl->gl_sbd; |
940 | struct list_head *insert_pt = NULL; | |
941 | struct gfs2_holder *gh2; | |
e5dc76b9 | 942 | int try_futile = 0; |
b3b94faa | 943 | |
b1e058da | 944 | BUG_ON(gh->gh_owner_pid == NULL); |
fee852e3 SW |
945 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
946 | BUG(); | |
190562bd | 947 | |
6802e340 SW |
948 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { |
949 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
e5dc76b9 | 950 | try_futile = !may_grant(gl, gh); |
6802e340 SW |
951 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) |
952 | goto fail; | |
953 | } | |
954 | ||
955 | list_for_each_entry(gh2, &gl->gl_holders, gh_list) { | |
956 | if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && | |
957 | (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK))) | |
958 | goto trap_recursive; | |
e5dc76b9 BP |
959 | if (try_futile && |
960 | !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { | |
6802e340 SW |
961 | fail: |
962 | gh->gh_error = GLR_TRYFAILED; | |
963 | gfs2_holder_wake(gh); | |
964 | return; | |
b4c20166 | 965 | } |
6802e340 SW |
966 | if (test_bit(HIF_HOLDER, &gh2->gh_iflags)) |
967 | continue; | |
968 | if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt)) | |
969 | insert_pt = &gh2->gh_list; | |
970 | } | |
7b5e3d5f | 971 | set_bit(GLF_QUEUED, &gl->gl_flags); |
edae38a6 | 972 | trace_gfs2_glock_queue(gh, 1); |
a245769f SW |
973 | gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT); |
974 | gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT); | |
6802e340 SW |
975 | if (likely(insert_pt == NULL)) { |
976 | list_add_tail(&gh->gh_list, &gl->gl_holders); | |
977 | if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY)) | |
978 | goto do_cancel; | |
979 | return; | |
980 | } | |
981 | list_add_tail(&gh->gh_list, insert_pt); | |
982 | do_cancel: | |
983 | gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list); | |
984 | if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
985 | spin_unlock(&gl->gl_spin); | |
048bca22 | 986 | if (sdp->sd_lockstruct.ls_ops->lm_cancel) |
f057f6cd | 987 | sdp->sd_lockstruct.ls_ops->lm_cancel(gl); |
6802e340 | 988 | spin_lock(&gl->gl_spin); |
b3b94faa | 989 | } |
6802e340 | 990 | return; |
b3b94faa | 991 | |
6802e340 | 992 | trap_recursive: |
fc554ed3 FF |
993 | pr_err("original: %pSR\n", (void *)gh2->gh_ip); |
994 | pr_err("pid: %d\n", pid_nr(gh2->gh_owner_pid)); | |
995 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 996 | gh2->gh_gl->gl_name.ln_type, gh2->gh_state); |
fc554ed3 FF |
997 | pr_err("new: %pSR\n", (void *)gh->gh_ip); |
998 | pr_err("pid: %d\n", pid_nr(gh->gh_owner_pid)); | |
999 | pr_err("lock type: %d req lock state : %d\n", | |
6802e340 | 1000 | gh->gh_gl->gl_name.ln_type, gh->gh_state); |
8eae1ca0 | 1001 | gfs2_dump_glock(NULL, gl); |
6802e340 | 1002 | BUG(); |
b3b94faa DT |
1003 | } |
1004 | ||
1005 | /** | |
1006 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1007 | * @gh: the holder structure | |
1008 | * | |
1009 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1010 | * | |
1011 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1012 | */ | |
1013 | ||
1014 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1015 | { | |
1016 | struct gfs2_glock *gl = gh->gh_gl; | |
1017 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1018 | int error = 0; | |
1019 | ||
6802e340 | 1020 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
b3b94faa | 1021 | return -EIO; |
b3b94faa | 1022 | |
f42ab085 SW |
1023 | if (test_bit(GLF_LRU, &gl->gl_flags)) |
1024 | gfs2_glock_remove_from_lru(gl); | |
1025 | ||
b3b94faa DT |
1026 | spin_lock(&gl->gl_spin); |
1027 | add_to_queue(gh); | |
01b172b7 BP |
1028 | if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) && |
1029 | test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) { | |
0809f6ec | 1030 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
01b172b7 BP |
1031 | gl->gl_lockref.count++; |
1032 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) | |
1033 | gl->gl_lockref.count--; | |
1034 | } | |
6802e340 | 1035 | run_queue(gl, 1); |
b3b94faa DT |
1036 | spin_unlock(&gl->gl_spin); |
1037 | ||
6802e340 SW |
1038 | if (!(gh->gh_flags & GL_ASYNC)) |
1039 | error = gfs2_glock_wait(gh); | |
b3b94faa | 1040 | |
b3b94faa DT |
1041 | return error; |
1042 | } | |
1043 | ||
1044 | /** | |
1045 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1046 | * @gh: the holder | |
1047 | * | |
1048 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1049 | */ | |
1050 | ||
1051 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1052 | { | |
6802e340 | 1053 | return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1; |
b3b94faa DT |
1054 | } |
1055 | ||
1056 | /** | |
1057 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1058 | * @gh: the glock holder | |
1059 | * | |
1060 | */ | |
1061 | ||
1062 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1063 | { | |
1064 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1065 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
c4f68a13 | 1066 | unsigned delay = 0; |
6802e340 | 1067 | int fast_path = 0; |
b3b94faa | 1068 | |
6802e340 | 1069 | spin_lock(&gl->gl_spin); |
b3b94faa | 1070 | if (gh->gh_flags & GL_NOCACHE) |
81ffbf65 | 1071 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
b3b94faa | 1072 | |
b3b94faa | 1073 | list_del_init(&gh->gh_list); |
6802e340 | 1074 | if (find_first_holder(gl) == NULL) { |
3042a2cc | 1075 | if (glops->go_unlock) { |
6802e340 | 1076 | GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags)); |
3042a2cc | 1077 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1078 | glops->go_unlock(gh); |
3042a2cc | 1079 | spin_lock(&gl->gl_spin); |
6802e340 | 1080 | clear_bit(GLF_LOCK, &gl->gl_flags); |
3042a2cc | 1081 | } |
6802e340 SW |
1082 | if (list_empty(&gl->gl_holders) && |
1083 | !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
1084 | !test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1085 | fast_path = 1; | |
b3b94faa | 1086 | } |
4abb6ad9 BP |
1087 | if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl)) |
1088 | gfs2_glock_add_to_lru(gl); | |
1089 | ||
63997775 | 1090 | trace_gfs2_glock_queue(gh, 0); |
b3b94faa | 1091 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1092 | if (likely(fast_path)) |
1093 | return; | |
c4f68a13 BM |
1094 | |
1095 | gfs2_glock_hold(gl); | |
1096 | if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && | |
7cf8dcd3 BP |
1097 | !test_bit(GLF_DEMOTE, &gl->gl_flags) && |
1098 | gl->gl_name.ln_type == LM_TYPE_INODE) | |
1099 | delay = gl->gl_hold_time; | |
c4f68a13 BM |
1100 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1101 | gfs2_glock_put(gl); | |
b3b94faa DT |
1102 | } |
1103 | ||
d93cfa98 AD |
1104 | void gfs2_glock_dq_wait(struct gfs2_holder *gh) |
1105 | { | |
1106 | struct gfs2_glock *gl = gh->gh_gl; | |
1107 | gfs2_glock_dq(gh); | |
81e1d450 | 1108 | might_sleep(); |
74316201 | 1109 | wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE); |
d93cfa98 AD |
1110 | } |
1111 | ||
b3b94faa DT |
1112 | /** |
1113 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1114 | * @gh: the holder structure | |
1115 | * | |
1116 | */ | |
1117 | ||
1118 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1119 | { | |
1120 | gfs2_glock_dq(gh); | |
1121 | gfs2_holder_uninit(gh); | |
1122 | } | |
1123 | ||
1124 | /** | |
1125 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1126 | * @sdp: the filesystem | |
1127 | * @number: the lock number | |
1128 | * @glops: the glock operations for the type of glock | |
1129 | * @state: the state to acquire the glock in | |
25985edc | 1130 | * @flags: modifier flags for the acquisition |
b3b94faa DT |
1131 | * @gh: the struct gfs2_holder |
1132 | * | |
1133 | * Returns: errno | |
1134 | */ | |
1135 | ||
cd915493 | 1136 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1137 | const struct gfs2_glock_operations *glops, |
1138 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1139 | { |
1140 | struct gfs2_glock *gl; | |
1141 | int error; | |
1142 | ||
1143 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1144 | if (!error) { | |
1145 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1146 | gfs2_glock_put(gl); | |
1147 | } | |
1148 | ||
1149 | return error; | |
1150 | } | |
1151 | ||
1152 | /** | |
1153 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1154 | * @arg_a: the first structure | |
1155 | * @arg_b: the second structure | |
1156 | * | |
1157 | */ | |
1158 | ||
1159 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1160 | { | |
a5e08a9e SW |
1161 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1162 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1163 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1164 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1165 | |
1166 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1167 | return 1; |
1168 | if (a->ln_number < b->ln_number) | |
1169 | return -1; | |
1c0f4872 | 1170 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1171 | return 0; |
b3b94faa DT |
1172 | } |
1173 | ||
1174 | /** | |
1175 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1176 | * @num_gh: the number of structures | |
1177 | * @ghs: an array of struct gfs2_holder structures | |
1178 | * | |
1179 | * Returns: 0 on success (all glocks acquired), | |
1180 | * errno on failure (no glocks acquired) | |
1181 | */ | |
1182 | ||
1183 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1184 | struct gfs2_holder **p) | |
1185 | { | |
1186 | unsigned int x; | |
1187 | int error = 0; | |
1188 | ||
1189 | for (x = 0; x < num_gh; x++) | |
1190 | p[x] = &ghs[x]; | |
1191 | ||
1192 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1193 | ||
1194 | for (x = 0; x < num_gh; x++) { | |
1195 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1196 | ||
1197 | error = gfs2_glock_nq(p[x]); | |
1198 | if (error) { | |
1199 | while (x--) | |
1200 | gfs2_glock_dq(p[x]); | |
1201 | break; | |
1202 | } | |
1203 | } | |
1204 | ||
1205 | return error; | |
1206 | } | |
1207 | ||
1208 | /** | |
1209 | * gfs2_glock_nq_m - acquire multiple glocks | |
1210 | * @num_gh: the number of structures | |
1211 | * @ghs: an array of struct gfs2_holder structures | |
1212 | * | |
b3b94faa DT |
1213 | * |
1214 | * Returns: 0 on success (all glocks acquired), | |
1215 | * errno on failure (no glocks acquired) | |
1216 | */ | |
1217 | ||
1218 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1219 | { | |
eaf5bd3c SW |
1220 | struct gfs2_holder *tmp[4]; |
1221 | struct gfs2_holder **pph = tmp; | |
b3b94faa DT |
1222 | int error = 0; |
1223 | ||
eaf5bd3c SW |
1224 | switch(num_gh) { |
1225 | case 0: | |
b3b94faa | 1226 | return 0; |
eaf5bd3c | 1227 | case 1: |
b3b94faa DT |
1228 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); |
1229 | return gfs2_glock_nq(ghs); | |
eaf5bd3c SW |
1230 | default: |
1231 | if (num_gh <= 4) | |
b3b94faa | 1232 | break; |
eaf5bd3c SW |
1233 | pph = kmalloc(num_gh * sizeof(struct gfs2_holder *), GFP_NOFS); |
1234 | if (!pph) | |
1235 | return -ENOMEM; | |
b3b94faa DT |
1236 | } |
1237 | ||
eaf5bd3c | 1238 | error = nq_m_sync(num_gh, ghs, pph); |
b3b94faa | 1239 | |
eaf5bd3c SW |
1240 | if (pph != tmp) |
1241 | kfree(pph); | |
b3b94faa DT |
1242 | |
1243 | return error; | |
1244 | } | |
1245 | ||
1246 | /** | |
1247 | * gfs2_glock_dq_m - release multiple glocks | |
1248 | * @num_gh: the number of structures | |
1249 | * @ghs: an array of struct gfs2_holder structures | |
1250 | * | |
1251 | */ | |
1252 | ||
1253 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1254 | { | |
fa1bbdea BP |
1255 | while (num_gh--) |
1256 | gfs2_glock_dq(&ghs[num_gh]); | |
b3b94faa DT |
1257 | } |
1258 | ||
f057f6cd | 1259 | void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) |
da755fdb | 1260 | { |
c4f68a13 BM |
1261 | unsigned long delay = 0; |
1262 | unsigned long holdtime; | |
1263 | unsigned long now = jiffies; | |
b3b94faa | 1264 | |
f057f6cd | 1265 | gfs2_glock_hold(gl); |
7cf8dcd3 BP |
1266 | holdtime = gl->gl_tchange + gl->gl_hold_time; |
1267 | if (test_bit(GLF_QUEUED, &gl->gl_flags) && | |
1268 | gl->gl_name.ln_type == LM_TYPE_INODE) { | |
7b5e3d5f SW |
1269 | if (time_before(now, holdtime)) |
1270 | delay = holdtime - now; | |
1271 | if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags)) | |
7cf8dcd3 | 1272 | delay = gl->gl_hold_time; |
7b5e3d5f | 1273 | } |
b3b94faa | 1274 | |
6802e340 | 1275 | spin_lock(&gl->gl_spin); |
81ffbf65 | 1276 | handle_callback(gl, state, delay, true); |
6802e340 | 1277 | spin_unlock(&gl->gl_spin); |
c4f68a13 BM |
1278 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0) |
1279 | gfs2_glock_put(gl); | |
b3b94faa DT |
1280 | } |
1281 | ||
0809f6ec SW |
1282 | /** |
1283 | * gfs2_should_freeze - Figure out if glock should be frozen | |
1284 | * @gl: The glock in question | |
1285 | * | |
1286 | * Glocks are not frozen if (a) the result of the dlm operation is | |
1287 | * an error, (b) the locking operation was an unlock operation or | |
1288 | * (c) if there is a "noexp" flagged request anywhere in the queue | |
1289 | * | |
1290 | * Returns: 1 if freezing should occur, 0 otherwise | |
1291 | */ | |
1292 | ||
1293 | static int gfs2_should_freeze(const struct gfs2_glock *gl) | |
1294 | { | |
1295 | const struct gfs2_holder *gh; | |
1296 | ||
1297 | if (gl->gl_reply & ~LM_OUT_ST_MASK) | |
1298 | return 0; | |
1299 | if (gl->gl_target == LM_ST_UNLOCKED) | |
1300 | return 0; | |
1301 | ||
1302 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
1303 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1304 | continue; | |
1305 | if (LM_FLAG_NOEXP & gh->gh_flags) | |
1306 | return 0; | |
1307 | } | |
1308 | ||
1309 | return 1; | |
1310 | } | |
1311 | ||
b3b94faa | 1312 | /** |
f057f6cd SW |
1313 | * gfs2_glock_complete - Callback used by locking |
1314 | * @gl: Pointer to the glock | |
1315 | * @ret: The return value from the dlm | |
b3b94faa | 1316 | * |
47a25380 SW |
1317 | * The gl_reply field is under the gl_spin lock so that it is ok |
1318 | * to use a bitfield shared with other glock state fields. | |
b3b94faa DT |
1319 | */ |
1320 | ||
f057f6cd | 1321 | void gfs2_glock_complete(struct gfs2_glock *gl, int ret) |
b3b94faa | 1322 | { |
f057f6cd | 1323 | struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; |
0809f6ec | 1324 | |
47a25380 | 1325 | spin_lock(&gl->gl_spin); |
f057f6cd | 1326 | gl->gl_reply = ret; |
0809f6ec | 1327 | |
e0c2a9aa | 1328 | if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) { |
0809f6ec | 1329 | if (gfs2_should_freeze(gl)) { |
f057f6cd | 1330 | set_bit(GLF_FROZEN, &gl->gl_flags); |
0809f6ec | 1331 | spin_unlock(&gl->gl_spin); |
b3b94faa | 1332 | return; |
0809f6ec | 1333 | } |
b3b94faa | 1334 | } |
47a25380 | 1335 | |
e66cf161 | 1336 | gl->gl_lockref.count++; |
f057f6cd | 1337 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
e66cf161 SW |
1338 | spin_unlock(&gl->gl_spin); |
1339 | ||
f057f6cd SW |
1340 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1341 | gfs2_glock_put(gl); | |
b3b94faa DT |
1342 | } |
1343 | ||
4506a519 SW |
1344 | static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) |
1345 | { | |
1346 | struct gfs2_glock *gla, *glb; | |
1347 | ||
1348 | gla = list_entry(a, struct gfs2_glock, gl_lru); | |
1349 | glb = list_entry(b, struct gfs2_glock, gl_lru); | |
1350 | ||
1351 | if (gla->gl_name.ln_number > glb->gl_name.ln_number) | |
1352 | return 1; | |
1353 | if (gla->gl_name.ln_number < glb->gl_name.ln_number) | |
1354 | return -1; | |
1355 | ||
1356 | return 0; | |
1357 | } | |
1358 | ||
1359 | /** | |
1360 | * gfs2_dispose_glock_lru - Demote a list of glocks | |
1361 | * @list: The list to dispose of | |
1362 | * | |
1363 | * Disposing of glocks may involve disk accesses, so that here we sort | |
1364 | * the glocks by number (i.e. disk location of the inodes) so that if | |
1365 | * there are any such accesses, they'll be sent in order (mostly). | |
1366 | * | |
1367 | * Must be called under the lru_lock, but may drop and retake this | |
1368 | * lock. While the lru_lock is dropped, entries may vanish from the | |
1369 | * list, but no new entries will appear on the list (since it is | |
1370 | * private) | |
1371 | */ | |
1372 | ||
1373 | static void gfs2_dispose_glock_lru(struct list_head *list) | |
1374 | __releases(&lru_lock) | |
1375 | __acquires(&lru_lock) | |
1376 | { | |
1377 | struct gfs2_glock *gl; | |
1378 | ||
1379 | list_sort(NULL, list, glock_cmp); | |
1380 | ||
1381 | while(!list_empty(list)) { | |
1382 | gl = list_entry(list->next, struct gfs2_glock, gl_lru); | |
1383 | list_del_init(&gl->gl_lru); | |
e66cf161 | 1384 | if (!spin_trylock(&gl->gl_spin)) { |
94a09a39 | 1385 | add_back_to_lru: |
e66cf161 SW |
1386 | list_add(&gl->gl_lru, &lru_list); |
1387 | atomic_inc(&lru_count); | |
1388 | continue; | |
1389 | } | |
94a09a39 SW |
1390 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
1391 | spin_unlock(&gl->gl_spin); | |
1392 | goto add_back_to_lru; | |
1393 | } | |
4506a519 | 1394 | clear_bit(GLF_LRU, &gl->gl_flags); |
e66cf161 | 1395 | gl->gl_lockref.count++; |
4506a519 | 1396 | if (demote_ok(gl)) |
81ffbf65 | 1397 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
4506a519 | 1398 | WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); |
4506a519 | 1399 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
e66cf161 | 1400 | gl->gl_lockref.count--; |
4506a519 | 1401 | spin_unlock(&gl->gl_spin); |
94a09a39 | 1402 | cond_resched_lock(&lru_lock); |
4506a519 SW |
1403 | } |
1404 | } | |
1405 | ||
2a005855 SW |
1406 | /** |
1407 | * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote | |
1408 | * @nr: The number of entries to scan | |
1409 | * | |
4506a519 SW |
1410 | * This function selects the entries on the LRU which are able to |
1411 | * be demoted, and then kicks off the process by calling | |
1412 | * gfs2_dispose_glock_lru() above. | |
2a005855 | 1413 | */ |
b3b94faa | 1414 | |
1ab6c499 | 1415 | static long gfs2_scan_glock_lru(int nr) |
b3b94faa DT |
1416 | { |
1417 | struct gfs2_glock *gl; | |
97cc1025 | 1418 | LIST_HEAD(skipped); |
4506a519 | 1419 | LIST_HEAD(dispose); |
1ab6c499 | 1420 | long freed = 0; |
b3b94faa | 1421 | |
97cc1025 | 1422 | spin_lock(&lru_lock); |
1ab6c499 | 1423 | while ((nr-- >= 0) && !list_empty(&lru_list)) { |
97cc1025 | 1424 | gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru); |
97cc1025 SW |
1425 | |
1426 | /* Test for being demotable */ | |
94a09a39 | 1427 | if (!test_bit(GLF_LOCK, &gl->gl_flags)) { |
4506a519 SW |
1428 | list_move(&gl->gl_lru, &dispose); |
1429 | atomic_dec(&lru_count); | |
1ab6c499 | 1430 | freed++; |
2163b1e6 | 1431 | continue; |
97cc1025 | 1432 | } |
4506a519 SW |
1433 | |
1434 | list_move(&gl->gl_lru, &skipped); | |
b3b94faa | 1435 | } |
97cc1025 | 1436 | list_splice(&skipped, &lru_list); |
4506a519 SW |
1437 | if (!list_empty(&dispose)) |
1438 | gfs2_dispose_glock_lru(&dispose); | |
97cc1025 | 1439 | spin_unlock(&lru_lock); |
1ab6c499 DC |
1440 | |
1441 | return freed; | |
2a005855 SW |
1442 | } |
1443 | ||
1ab6c499 DC |
1444 | static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink, |
1445 | struct shrink_control *sc) | |
2a005855 | 1446 | { |
1ab6c499 DC |
1447 | if (!(sc->gfp_mask & __GFP_FS)) |
1448 | return SHRINK_STOP; | |
1449 | return gfs2_scan_glock_lru(sc->nr_to_scan); | |
1450 | } | |
2a005855 | 1451 | |
1ab6c499 DC |
1452 | static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink, |
1453 | struct shrink_control *sc) | |
1454 | { | |
55f841ce | 1455 | return vfs_pressure_ratio(atomic_read(&lru_count)); |
b3b94faa DT |
1456 | } |
1457 | ||
97cc1025 | 1458 | static struct shrinker glock_shrinker = { |
97cc1025 | 1459 | .seeks = DEFAULT_SEEKS, |
1ab6c499 DC |
1460 | .count_objects = gfs2_glock_shrink_count, |
1461 | .scan_objects = gfs2_glock_shrink_scan, | |
97cc1025 SW |
1462 | }; |
1463 | ||
b3b94faa DT |
1464 | /** |
1465 | * examine_bucket - Call a function for glock in a hash bucket | |
1466 | * @examiner: the function | |
1467 | * @sdp: the filesystem | |
1468 | * @bucket: the bucket | |
1469 | * | |
b3b94faa DT |
1470 | */ |
1471 | ||
bc015cb8 | 1472 | static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, |
37b2fa6a | 1473 | unsigned int hash) |
b3b94faa | 1474 | { |
bc015cb8 SW |
1475 | struct gfs2_glock *gl; |
1476 | struct hlist_bl_head *head = &gl_hash_table[hash]; | |
1477 | struct hlist_bl_node *pos; | |
b3b94faa | 1478 | |
bc015cb8 SW |
1479 | rcu_read_lock(); |
1480 | hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { | |
e66cf161 | 1481 | if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref)) |
24264434 | 1482 | examiner(gl); |
b3b94faa | 1483 | } |
bc015cb8 | 1484 | rcu_read_unlock(); |
8fbbfd21 | 1485 | cond_resched(); |
bc015cb8 SW |
1486 | } |
1487 | ||
1488 | static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp) | |
1489 | { | |
1490 | unsigned x; | |
1491 | ||
1492 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) | |
1493 | examine_bucket(examiner, sdp, x); | |
b3b94faa DT |
1494 | } |
1495 | ||
f057f6cd SW |
1496 | |
1497 | /** | |
1498 | * thaw_glock - thaw out a glock which has an unprocessed reply waiting | |
1499 | * @gl: The glock to thaw | |
1500 | * | |
f057f6cd SW |
1501 | */ |
1502 | ||
1503 | static void thaw_glock(struct gfs2_glock *gl) | |
1504 | { | |
1505 | if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) | |
7286b31e | 1506 | goto out; |
f057f6cd | 1507 | set_bit(GLF_REPLY_PENDING, &gl->gl_flags); |
7286b31e SW |
1508 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) { |
1509 | out: | |
f057f6cd | 1510 | gfs2_glock_put(gl); |
7286b31e | 1511 | } |
f057f6cd SW |
1512 | } |
1513 | ||
b3b94faa DT |
1514 | /** |
1515 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1516 | * @gl: the glock to look at | |
1517 | * | |
1518 | */ | |
1519 | ||
1520 | static void clear_glock(struct gfs2_glock *gl) | |
1521 | { | |
f42ab085 | 1522 | gfs2_glock_remove_from_lru(gl); |
b3b94faa | 1523 | |
6802e340 | 1524 | spin_lock(&gl->gl_spin); |
c741c455 | 1525 | if (gl->gl_state != LM_ST_UNLOCKED) |
81ffbf65 | 1526 | handle_callback(gl, LM_ST_UNLOCKED, 0, false); |
6802e340 | 1527 | spin_unlock(&gl->gl_spin); |
6802e340 SW |
1528 | if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) |
1529 | gfs2_glock_put(gl); | |
b3b94faa DT |
1530 | } |
1531 | ||
f057f6cd SW |
1532 | /** |
1533 | * gfs2_glock_thaw - Thaw any frozen glocks | |
1534 | * @sdp: The super block | |
1535 | * | |
1536 | */ | |
1537 | ||
1538 | void gfs2_glock_thaw(struct gfs2_sbd *sdp) | |
1539 | { | |
bc015cb8 SW |
1540 | glock_hash_walk(thaw_glock, sdp); |
1541 | } | |
f057f6cd | 1542 | |
ac3beb6a | 1543 | static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl) |
bc015cb8 | 1544 | { |
bc015cb8 | 1545 | spin_lock(&gl->gl_spin); |
ac3beb6a | 1546 | gfs2_dump_glock(seq, gl); |
bc015cb8 | 1547 | spin_unlock(&gl->gl_spin); |
bc015cb8 SW |
1548 | } |
1549 | ||
1550 | static void dump_glock_func(struct gfs2_glock *gl) | |
1551 | { | |
1552 | dump_glock(NULL, gl); | |
f057f6cd SW |
1553 | } |
1554 | ||
b3b94faa DT |
1555 | /** |
1556 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1557 | * @sdp: the filesystem | |
1558 | * @wait: wait until it's all gone | |
1559 | * | |
1bdad606 | 1560 | * Called when unmounting the filesystem. |
b3b94faa DT |
1561 | */ |
1562 | ||
fefc03bf | 1563 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) |
b3b94faa | 1564 | { |
fb6791d1 | 1565 | set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags); |
222cb538 | 1566 | flush_workqueue(glock_workqueue); |
bc015cb8 | 1567 | glock_hash_walk(clear_glock, sdp); |
8f05228e SW |
1568 | flush_workqueue(glock_workqueue); |
1569 | wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0); | |
bc015cb8 | 1570 | glock_hash_walk(dump_glock_func, sdp); |
b3b94faa DT |
1571 | } |
1572 | ||
813e0c46 SW |
1573 | void gfs2_glock_finish_truncate(struct gfs2_inode *ip) |
1574 | { | |
1575 | struct gfs2_glock *gl = ip->i_gl; | |
1576 | int ret; | |
1577 | ||
1578 | ret = gfs2_truncatei_resume(ip); | |
1579 | gfs2_assert_withdraw(gl->gl_sbd, ret == 0); | |
1580 | ||
1581 | spin_lock(&gl->gl_spin); | |
1582 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1583 | run_queue(gl, 1); | |
1584 | spin_unlock(&gl->gl_spin); | |
1585 | } | |
1586 | ||
6802e340 | 1587 | static const char *state2str(unsigned state) |
04b933f2 | 1588 | { |
6802e340 SW |
1589 | switch(state) { |
1590 | case LM_ST_UNLOCKED: | |
1591 | return "UN"; | |
1592 | case LM_ST_SHARED: | |
1593 | return "SH"; | |
1594 | case LM_ST_DEFERRED: | |
1595 | return "DF"; | |
1596 | case LM_ST_EXCLUSIVE: | |
1597 | return "EX"; | |
1598 | } | |
1599 | return "??"; | |
1600 | } | |
1601 | ||
1602 | static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) | |
1603 | { | |
1604 | char *p = buf; | |
1605 | if (flags & LM_FLAG_TRY) | |
1606 | *p++ = 't'; | |
1607 | if (flags & LM_FLAG_TRY_1CB) | |
1608 | *p++ = 'T'; | |
1609 | if (flags & LM_FLAG_NOEXP) | |
1610 | *p++ = 'e'; | |
1611 | if (flags & LM_FLAG_ANY) | |
f057f6cd | 1612 | *p++ = 'A'; |
6802e340 SW |
1613 | if (flags & LM_FLAG_PRIORITY) |
1614 | *p++ = 'p'; | |
1615 | if (flags & GL_ASYNC) | |
1616 | *p++ = 'a'; | |
1617 | if (flags & GL_EXACT) | |
1618 | *p++ = 'E'; | |
6802e340 SW |
1619 | if (flags & GL_NOCACHE) |
1620 | *p++ = 'c'; | |
1621 | if (test_bit(HIF_HOLDER, &iflags)) | |
1622 | *p++ = 'H'; | |
1623 | if (test_bit(HIF_WAIT, &iflags)) | |
1624 | *p++ = 'W'; | |
1625 | if (test_bit(HIF_FIRST, &iflags)) | |
1626 | *p++ = 'F'; | |
1627 | *p = 0; | |
1628 | return buf; | |
04b933f2 RP |
1629 | } |
1630 | ||
b3b94faa DT |
1631 | /** |
1632 | * dump_holder - print information about a glock holder | |
6802e340 | 1633 | * @seq: the seq_file struct |
b3b94faa DT |
1634 | * @gh: the glock holder |
1635 | * | |
b3b94faa DT |
1636 | */ |
1637 | ||
ac3beb6a | 1638 | static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh) |
b3b94faa | 1639 | { |
6802e340 | 1640 | struct task_struct *gh_owner = NULL; |
6802e340 | 1641 | char flags_buf[32]; |
b3b94faa | 1642 | |
0b3a2c99 | 1643 | rcu_read_lock(); |
6802e340 | 1644 | if (gh->gh_owner_pid) |
b1e058da | 1645 | gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); |
cc18152e JP |
1646 | gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n", |
1647 | state2str(gh->gh_state), | |
1648 | hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), | |
1649 | gh->gh_error, | |
1650 | gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, | |
1651 | gh_owner ? gh_owner->comm : "(ended)", | |
1652 | (void *)gh->gh_ip); | |
0b3a2c99 | 1653 | rcu_read_unlock(); |
b3b94faa DT |
1654 | } |
1655 | ||
627c10b7 | 1656 | static const char *gflags2str(char *buf, const struct gfs2_glock *gl) |
6802e340 | 1657 | { |
627c10b7 | 1658 | const unsigned long *gflags = &gl->gl_flags; |
6802e340 | 1659 | char *p = buf; |
627c10b7 | 1660 | |
6802e340 SW |
1661 | if (test_bit(GLF_LOCK, gflags)) |
1662 | *p++ = 'l'; | |
6802e340 SW |
1663 | if (test_bit(GLF_DEMOTE, gflags)) |
1664 | *p++ = 'D'; | |
1665 | if (test_bit(GLF_PENDING_DEMOTE, gflags)) | |
1666 | *p++ = 'd'; | |
1667 | if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags)) | |
1668 | *p++ = 'p'; | |
1669 | if (test_bit(GLF_DIRTY, gflags)) | |
1670 | *p++ = 'y'; | |
1671 | if (test_bit(GLF_LFLUSH, gflags)) | |
1672 | *p++ = 'f'; | |
1673 | if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags)) | |
1674 | *p++ = 'i'; | |
1675 | if (test_bit(GLF_REPLY_PENDING, gflags)) | |
1676 | *p++ = 'r'; | |
f057f6cd | 1677 | if (test_bit(GLF_INITIAL, gflags)) |
d8348de0 | 1678 | *p++ = 'I'; |
f057f6cd SW |
1679 | if (test_bit(GLF_FROZEN, gflags)) |
1680 | *p++ = 'F'; | |
7b5e3d5f SW |
1681 | if (test_bit(GLF_QUEUED, gflags)) |
1682 | *p++ = 'q'; | |
627c10b7 SW |
1683 | if (test_bit(GLF_LRU, gflags)) |
1684 | *p++ = 'L'; | |
1685 | if (gl->gl_object) | |
1686 | *p++ = 'o'; | |
a245769f SW |
1687 | if (test_bit(GLF_BLOCKING, gflags)) |
1688 | *p++ = 'b'; | |
6802e340 SW |
1689 | *p = 0; |
1690 | return buf; | |
b3b94faa DT |
1691 | } |
1692 | ||
1693 | /** | |
8eae1ca0 | 1694 | * gfs2_dump_glock - print information about a glock |
6802e340 | 1695 | * @seq: The seq_file struct |
b3b94faa | 1696 | * @gl: the glock |
6802e340 SW |
1697 | * |
1698 | * The file format is as follows: | |
1699 | * One line per object, capital letters are used to indicate objects | |
1700 | * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented, | |
1701 | * other objects are indented by a single space and follow the glock to | |
1702 | * which they are related. Fields are indicated by lower case letters | |
1703 | * followed by a colon and the field value, except for strings which are in | |
1704 | * [] so that its possible to see if they are composed of spaces for | |
1705 | * example. The field's are n = number (id of the object), f = flags, | |
1706 | * t = type, s = state, r = refcount, e = error, p = pid. | |
b3b94faa | 1707 | * |
b3b94faa DT |
1708 | */ |
1709 | ||
ac3beb6a | 1710 | void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) |
b3b94faa | 1711 | { |
6802e340 SW |
1712 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
1713 | unsigned long long dtime; | |
1714 | const struct gfs2_holder *gh; | |
1715 | char gflags_buf[32]; | |
b3b94faa | 1716 | |
6802e340 SW |
1717 | dtime = jiffies - gl->gl_demote_time; |
1718 | dtime *= 1000000/HZ; /* demote time in uSec */ | |
1719 | if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) | |
1720 | dtime = 0; | |
7cf8dcd3 | 1721 | 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 |
1722 | state2str(gl->gl_state), |
1723 | gl->gl_name.ln_type, | |
1724 | (unsigned long long)gl->gl_name.ln_number, | |
627c10b7 | 1725 | gflags2str(gflags_buf, gl), |
6802e340 SW |
1726 | state2str(gl->gl_target), |
1727 | state2str(gl->gl_demote_state), dtime, | |
6802e340 | 1728 | atomic_read(&gl->gl_ail_count), |
f42ab085 | 1729 | atomic_read(&gl->gl_revokes), |
e66cf161 | 1730 | (int)gl->gl_lockref.count, gl->gl_hold_time); |
b3b94faa | 1731 | |
ac3beb6a SW |
1732 | list_for_each_entry(gh, &gl->gl_holders, gh_list) |
1733 | dump_holder(seq, gh); | |
1734 | ||
6802e340 | 1735 | if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump) |
ac3beb6a | 1736 | glops->go_dump(seq, gl); |
b3b94faa DT |
1737 | } |
1738 | ||
a245769f SW |
1739 | static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr) |
1740 | { | |
1741 | struct gfs2_glock *gl = iter_ptr; | |
1742 | ||
1743 | seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n", | |
1744 | gl->gl_name.ln_type, | |
1745 | (unsigned long long)gl->gl_name.ln_number, | |
1746 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTT], | |
1747 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR], | |
1748 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB], | |
1749 | (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB], | |
1750 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRT], | |
1751 | (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR], | |
1752 | (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT], | |
1753 | (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]); | |
1754 | return 0; | |
1755 | } | |
1756 | ||
1757 | static const char *gfs2_gltype[] = { | |
1758 | "type", | |
1759 | "reserved", | |
1760 | "nondisk", | |
1761 | "inode", | |
1762 | "rgrp", | |
1763 | "meta", | |
1764 | "iopen", | |
1765 | "flock", | |
1766 | "plock", | |
1767 | "quota", | |
1768 | "journal", | |
1769 | }; | |
1770 | ||
1771 | static const char *gfs2_stype[] = { | |
1772 | [GFS2_LKS_SRTT] = "srtt", | |
1773 | [GFS2_LKS_SRTTVAR] = "srttvar", | |
1774 | [GFS2_LKS_SRTTB] = "srttb", | |
1775 | [GFS2_LKS_SRTTVARB] = "srttvarb", | |
1776 | [GFS2_LKS_SIRT] = "sirt", | |
1777 | [GFS2_LKS_SIRTVAR] = "sirtvar", | |
1778 | [GFS2_LKS_DCOUNT] = "dlm", | |
1779 | [GFS2_LKS_QCOUNT] = "queue", | |
1780 | }; | |
1781 | ||
1782 | #define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype)) | |
1783 | ||
1784 | static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr) | |
1785 | { | |
1786 | struct gfs2_glock_iter *gi = seq->private; | |
1787 | struct gfs2_sbd *sdp = gi->sdp; | |
1788 | unsigned index = gi->hash >> 3; | |
1789 | unsigned subindex = gi->hash & 0x07; | |
1790 | s64 value; | |
1791 | int i; | |
1792 | ||
1793 | if (index == 0 && subindex != 0) | |
1794 | return 0; | |
6802e340 | 1795 | |
a245769f SW |
1796 | seq_printf(seq, "%-10s %8s:", gfs2_gltype[index], |
1797 | (index == 0) ? "cpu": gfs2_stype[subindex]); | |
b3b94faa | 1798 | |
a245769f SW |
1799 | for_each_possible_cpu(i) { |
1800 | const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i); | |
1801 | if (index == 0) { | |
1802 | value = i; | |
1803 | } else { | |
1804 | value = lkstats->lkstats[index - 1].stats[subindex]; | |
1805 | } | |
1806 | seq_printf(seq, " %15lld", (long long)value); | |
1807 | } | |
1808 | seq_putc(seq, '\n'); | |
1809 | return 0; | |
1810 | } | |
8fbbfd21 | 1811 | |
85d1da67 SW |
1812 | int __init gfs2_glock_init(void) |
1813 | { | |
1814 | unsigned i; | |
1815 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
bc015cb8 | 1816 | INIT_HLIST_BL_HEAD(&gl_hash_table[i]); |
087efdd3 | 1817 | } |
8fbbfd21 | 1818 | |
d2115778 | 1819 | glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM | |
58a69cb4 | 1820 | WQ_HIGHPRI | WQ_FREEZABLE, 0); |
dfc4616d DC |
1821 | if (!glock_workqueue) |
1822 | return -ENOMEM; | |
d2115778 | 1823 | gfs2_delete_workqueue = alloc_workqueue("delete_workqueue", |
58a69cb4 | 1824 | WQ_MEM_RECLAIM | WQ_FREEZABLE, |
d2115778 | 1825 | 0); |
dfc4616d | 1826 | if (!gfs2_delete_workqueue) { |
b94a170e | 1827 | destroy_workqueue(glock_workqueue); |
dfc4616d | 1828 | return -ENOMEM; |
b94a170e | 1829 | } |
97cc1025 SW |
1830 | |
1831 | register_shrinker(&glock_shrinker); | |
c4f68a13 | 1832 | |
85d1da67 SW |
1833 | return 0; |
1834 | } | |
1835 | ||
8fbbfd21 SW |
1836 | void gfs2_glock_exit(void) |
1837 | { | |
97cc1025 | 1838 | unregister_shrinker(&glock_shrinker); |
c4f68a13 | 1839 | destroy_workqueue(glock_workqueue); |
b94a170e | 1840 | destroy_workqueue(gfs2_delete_workqueue); |
8fbbfd21 SW |
1841 | } |
1842 | ||
bc015cb8 SW |
1843 | static inline struct gfs2_glock *glock_hash_chain(unsigned hash) |
1844 | { | |
1845 | return hlist_bl_entry(hlist_bl_first_rcu(&gl_hash_table[hash]), | |
1846 | struct gfs2_glock, gl_list); | |
1847 | } | |
1848 | ||
1849 | static inline struct gfs2_glock *glock_hash_next(struct gfs2_glock *gl) | |
1850 | { | |
7e32d026 | 1851 | return hlist_bl_entry(rcu_dereference(gl->gl_list.next), |
bc015cb8 SW |
1852 | struct gfs2_glock, gl_list); |
1853 | } | |
1854 | ||
6802e340 | 1855 | static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) |
7c52b166 | 1856 | { |
7b08fc62 SW |
1857 | struct gfs2_glock *gl; |
1858 | ||
bc015cb8 SW |
1859 | do { |
1860 | gl = gi->gl; | |
1861 | if (gl) { | |
1862 | gi->gl = glock_hash_next(gl); | |
ba1ddcb6 | 1863 | gi->nhash++; |
bc015cb8 | 1864 | } else { |
ba1ddcb6 SW |
1865 | if (gi->hash >= GFS2_GL_HASH_SIZE) { |
1866 | rcu_read_unlock(); | |
1867 | return 1; | |
1868 | } | |
bc015cb8 | 1869 | gi->gl = glock_hash_chain(gi->hash); |
ba1ddcb6 | 1870 | gi->nhash = 0; |
bc015cb8 SW |
1871 | } |
1872 | while (gi->gl == NULL) { | |
1873 | gi->hash++; | |
1874 | if (gi->hash >= GFS2_GL_HASH_SIZE) { | |
1875 | rcu_read_unlock(); | |
1876 | return 1; | |
1877 | } | |
1878 | gi->gl = glock_hash_chain(gi->hash); | |
ba1ddcb6 | 1879 | gi->nhash = 0; |
bc015cb8 SW |
1880 | } |
1881 | /* Skip entries for other sb and dead entries */ | |
e3c4269d MN |
1882 | } while (gi->sdp != gi->gl->gl_sbd || |
1883 | __lockref_is_dead(&gi->gl->gl_lockref)); | |
a947e033 | 1884 | |
7c52b166 RP |
1885 | return 0; |
1886 | } | |
1887 | ||
6802e340 | 1888 | static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) |
7c52b166 | 1889 | { |
6802e340 | 1890 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1891 | loff_t n = *pos; |
1892 | ||
ba1ddcb6 SW |
1893 | if (gi->last_pos <= *pos) |
1894 | n = gi->nhash + (*pos - gi->last_pos); | |
1895 | else | |
1896 | gi->hash = 0; | |
1897 | ||
1898 | gi->nhash = 0; | |
bc015cb8 | 1899 | rcu_read_lock(); |
7c52b166 | 1900 | |
6802e340 | 1901 | do { |
bc015cb8 | 1902 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1903 | return NULL; |
6802e340 | 1904 | } while (n--); |
7c52b166 | 1905 | |
ba1ddcb6 | 1906 | gi->last_pos = *pos; |
6802e340 | 1907 | return gi->gl; |
7c52b166 RP |
1908 | } |
1909 | ||
6802e340 | 1910 | static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr, |
7c52b166 RP |
1911 | loff_t *pos) |
1912 | { | |
6802e340 | 1913 | struct gfs2_glock_iter *gi = seq->private; |
7c52b166 RP |
1914 | |
1915 | (*pos)++; | |
ba1ddcb6 | 1916 | gi->last_pos = *pos; |
bc015cb8 | 1917 | if (gfs2_glock_iter_next(gi)) |
7c52b166 | 1918 | return NULL; |
7c52b166 | 1919 | |
6802e340 | 1920 | return gi->gl; |
7c52b166 RP |
1921 | } |
1922 | ||
6802e340 | 1923 | static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1924 | { |
6802e340 | 1925 | struct gfs2_glock_iter *gi = seq->private; |
bc015cb8 SW |
1926 | |
1927 | if (gi->gl) | |
1928 | rcu_read_unlock(); | |
1929 | gi->gl = NULL; | |
7c52b166 RP |
1930 | } |
1931 | ||
6802e340 | 1932 | static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr) |
7c52b166 | 1933 | { |
ac3beb6a SW |
1934 | dump_glock(seq, iter_ptr); |
1935 | return 0; | |
7c52b166 RP |
1936 | } |
1937 | ||
a245769f SW |
1938 | static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos) |
1939 | { | |
1940 | struct gfs2_glock_iter *gi = seq->private; | |
1941 | ||
1942 | gi->hash = *pos; | |
1943 | if (*pos >= GFS2_NR_SBSTATS) | |
1944 | return NULL; | |
1945 | preempt_disable(); | |
1946 | return SEQ_START_TOKEN; | |
1947 | } | |
1948 | ||
1949 | static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr, | |
1950 | loff_t *pos) | |
1951 | { | |
1952 | struct gfs2_glock_iter *gi = seq->private; | |
1953 | (*pos)++; | |
1954 | gi->hash++; | |
1955 | if (gi->hash >= GFS2_NR_SBSTATS) { | |
1956 | preempt_enable(); | |
1957 | return NULL; | |
1958 | } | |
1959 | return SEQ_START_TOKEN; | |
1960 | } | |
1961 | ||
1962 | static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr) | |
1963 | { | |
1964 | preempt_enable(); | |
1965 | } | |
1966 | ||
4ef29002 | 1967 | static const struct seq_operations gfs2_glock_seq_ops = { |
7c52b166 RP |
1968 | .start = gfs2_glock_seq_start, |
1969 | .next = gfs2_glock_seq_next, | |
1970 | .stop = gfs2_glock_seq_stop, | |
1971 | .show = gfs2_glock_seq_show, | |
1972 | }; | |
1973 | ||
a245769f SW |
1974 | static const struct seq_operations gfs2_glstats_seq_ops = { |
1975 | .start = gfs2_glock_seq_start, | |
1976 | .next = gfs2_glock_seq_next, | |
1977 | .stop = gfs2_glock_seq_stop, | |
1978 | .show = gfs2_glstats_seq_show, | |
1979 | }; | |
1980 | ||
1981 | static const struct seq_operations gfs2_sbstats_seq_ops = { | |
1982 | .start = gfs2_sbstats_seq_start, | |
1983 | .next = gfs2_sbstats_seq_next, | |
1984 | .stop = gfs2_sbstats_seq_stop, | |
1985 | .show = gfs2_sbstats_seq_show, | |
1986 | }; | |
1987 | ||
0fe2f1e9 SW |
1988 | #define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL) |
1989 | ||
a245769f | 1990 | static int gfs2_glocks_open(struct inode *inode, struct file *file) |
7c52b166 | 1991 | { |
6802e340 SW |
1992 | int ret = seq_open_private(file, &gfs2_glock_seq_ops, |
1993 | sizeof(struct gfs2_glock_iter)); | |
1994 | if (ret == 0) { | |
1995 | struct seq_file *seq = file->private_data; | |
1996 | struct gfs2_glock_iter *gi = seq->private; | |
1997 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 1998 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 1999 | if (seq->buf) |
0fe2f1e9 | 2000 | seq->size = GFS2_SEQ_GOODSIZE; |
6802e340 SW |
2001 | } |
2002 | return ret; | |
7c52b166 RP |
2003 | } |
2004 | ||
a245769f SW |
2005 | static int gfs2_glstats_open(struct inode *inode, struct file *file) |
2006 | { | |
2007 | int ret = seq_open_private(file, &gfs2_glstats_seq_ops, | |
2008 | sizeof(struct gfs2_glock_iter)); | |
2009 | if (ret == 0) { | |
2010 | struct seq_file *seq = file->private_data; | |
2011 | struct gfs2_glock_iter *gi = seq->private; | |
2012 | gi->sdp = inode->i_private; | |
0fe2f1e9 | 2013 | seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN); |
df5d2f55 | 2014 | if (seq->buf) |
0fe2f1e9 | 2015 | seq->size = GFS2_SEQ_GOODSIZE; |
a245769f SW |
2016 | } |
2017 | return ret; | |
2018 | } | |
2019 | ||
2020 | static int gfs2_sbstats_open(struct inode *inode, struct file *file) | |
2021 | { | |
2022 | int ret = seq_open_private(file, &gfs2_sbstats_seq_ops, | |
2023 | sizeof(struct gfs2_glock_iter)); | |
2024 | if (ret == 0) { | |
2025 | struct seq_file *seq = file->private_data; | |
2026 | struct gfs2_glock_iter *gi = seq->private; | |
2027 | gi->sdp = inode->i_private; | |
2028 | } | |
2029 | return ret; | |
2030 | } | |
2031 | ||
2032 | static const struct file_operations gfs2_glocks_fops = { | |
2033 | .owner = THIS_MODULE, | |
2034 | .open = gfs2_glocks_open, | |
2035 | .read = seq_read, | |
2036 | .llseek = seq_lseek, | |
2037 | .release = seq_release_private, | |
2038 | }; | |
2039 | ||
2040 | static const struct file_operations gfs2_glstats_fops = { | |
7c52b166 | 2041 | .owner = THIS_MODULE, |
a245769f SW |
2042 | .open = gfs2_glstats_open, |
2043 | .read = seq_read, | |
2044 | .llseek = seq_lseek, | |
2045 | .release = seq_release_private, | |
2046 | }; | |
2047 | ||
2048 | static const struct file_operations gfs2_sbstats_fops = { | |
2049 | .owner = THIS_MODULE, | |
2050 | .open = gfs2_sbstats_open, | |
7c52b166 RP |
2051 | .read = seq_read, |
2052 | .llseek = seq_lseek, | |
6802e340 | 2053 | .release = seq_release_private, |
7c52b166 RP |
2054 | }; |
2055 | ||
2056 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
2057 | { | |
5f882096 RP |
2058 | sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root); |
2059 | if (!sdp->debugfs_dir) | |
2060 | return -ENOMEM; | |
2061 | sdp->debugfs_dentry_glocks = debugfs_create_file("glocks", | |
2062 | S_IFREG | S_IRUGO, | |
2063 | sdp->debugfs_dir, sdp, | |
a245769f | 2064 | &gfs2_glocks_fops); |
5f882096 | 2065 | if (!sdp->debugfs_dentry_glocks) |
a245769f SW |
2066 | goto fail; |
2067 | ||
2068 | sdp->debugfs_dentry_glstats = debugfs_create_file("glstats", | |
2069 | S_IFREG | S_IRUGO, | |
2070 | sdp->debugfs_dir, sdp, | |
2071 | &gfs2_glstats_fops); | |
2072 | if (!sdp->debugfs_dentry_glstats) | |
2073 | goto fail; | |
2074 | ||
2075 | sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats", | |
2076 | S_IFREG | S_IRUGO, | |
2077 | sdp->debugfs_dir, sdp, | |
2078 | &gfs2_sbstats_fops); | |
2079 | if (!sdp->debugfs_dentry_sbstats) | |
2080 | goto fail; | |
7c52b166 RP |
2081 | |
2082 | return 0; | |
a245769f SW |
2083 | fail: |
2084 | gfs2_delete_debugfs_file(sdp); | |
2085 | return -ENOMEM; | |
7c52b166 RP |
2086 | } |
2087 | ||
2088 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) | |
2089 | { | |
a245769f | 2090 | if (sdp->debugfs_dir) { |
5f882096 RP |
2091 | if (sdp->debugfs_dentry_glocks) { |
2092 | debugfs_remove(sdp->debugfs_dentry_glocks); | |
2093 | sdp->debugfs_dentry_glocks = NULL; | |
2094 | } | |
a245769f SW |
2095 | if (sdp->debugfs_dentry_glstats) { |
2096 | debugfs_remove(sdp->debugfs_dentry_glstats); | |
2097 | sdp->debugfs_dentry_glstats = NULL; | |
2098 | } | |
2099 | if (sdp->debugfs_dentry_sbstats) { | |
2100 | debugfs_remove(sdp->debugfs_dentry_sbstats); | |
2101 | sdp->debugfs_dentry_sbstats = NULL; | |
2102 | } | |
5f882096 RP |
2103 | debugfs_remove(sdp->debugfs_dir); |
2104 | sdp->debugfs_dir = NULL; | |
2105 | } | |
7c52b166 RP |
2106 | } |
2107 | ||
2108 | int gfs2_register_debugfs(void) | |
2109 | { | |
2110 | gfs2_root = debugfs_create_dir("gfs2", NULL); | |
2111 | return gfs2_root ? 0 : -ENOMEM; | |
2112 | } | |
2113 | ||
2114 | void gfs2_unregister_debugfs(void) | |
2115 | { | |
2116 | debugfs_remove(gfs2_root); | |
5f882096 | 2117 | gfs2_root = NULL; |
7c52b166 | 2118 | } |